Companion Guide to the
ASME Boiler & Pressure Vessel Code
Criteria and Commentary on Select Aspects of the
Boiler & Pressure Vessel and Piping Codes
Fifth Edition
Volume 1
Editor
K. R. Rao
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Library of Congress Cataloging-in-Publication Data
Names: Rao, K. R., 1933- editor. | American Society of Mechanical Engineers, issuing body.
Title: Companion guide to the ASME boiler & pressure vessel code : criteria and commentary on select aspects of the boiler & pressure vessel
and piping codes.
Description: 5th edition. | New York : ASME, [2017] | Includes bibliographical references and index.
Identifiers: LCCN 2017043045 | ISBN 9780791861301 (alk. paper)
Subjects: LCSH: Steam-boilers--Standards. | Pressure vessels--Standards. | American Society of Mechanical Engineers. Boiler and Pressure
Vessel Committee. ASME boiler and pressure vessel code.
Classification: LCC TJ289 .C66 2017 | DDC 621.1/830218--dc23 LC record available at https://lccn.loc.gov/2017043045
Dedication to the First Edition
THIS MONUMENTAL EFFORT IS DEDICATED TO THE
ASME PRESSURE VESSELS AND PIPING DIVISION AND
TO TWO SIGNIFICANT CONTRIBUTORS TO THE DEVELOPMENT OF THE DESIGN-BY-ANALYSIS CONSTRUCTION
RULES IN THE MODERN ASME CODE.
This two-volume compendium dedication is not the first recognition of the achievements of Bernard F. Langer and William E.
Cooper. The Bernard F. Langer Nuclear Codes and Standards
Award, established in 1977, provides a posthumous and lasting
tribute to one of these contributors, an intellectual giant who was
instrumental in providing the leadership and statesmanship that
was essential to the creation of construction rules for nuclear vessels and related equipment. William E. Cooper, the first recipient
of the Bernard F. Langer Nuclear Codes and Standards Award, is
another intellectual giant instrumental in the creation of the modern ASME Code. In addition, Dr. Cooper acted in a number of
ASME Codes and Standards leadership positions. It was my pleasure to join many of my colleagues in April 2001 for the presentation to Dr. Cooper of the ASME President’s Award from the 120th
President of ASME International, William A. Weiblen. That most
prestigious award recognized a lifetime of achievement in ASME
and, in particular, in ASME Code activities.
Bernie Langer and Bill Cooper were essential in both the development of the modern ASME Code and in the creation of the
forums for technical information exchange that support the Code
rules. The publication of these two volumes by ASME International is a legacy of that duality. These volumes continue a long
and productive relationship between the development of the modern ASME Code and the technical exchanges on pressure vessel
and piping technology sponsored by the ASME Pressure Vessels
and Piping Technical Division. This process of technical information exchange, through conference paper and panel presentations,
and through refereed paper publication, is an essential step in the
reduction to standard practice, standard practice that is eventually
embodied in the rules of the ASME Code. Information exchange
at technical conferences and in technical publications goes hand in
hand with the deliberations of ASME Code bodies.
This relationship goes back to the pivotal events leading up to
the development of the modern ASME Code — the appointment
of the Special Committee to Review Code Stress Basis in the late
1950s. The principles formulated by that group became the basis
for Section III and Section VIII, Division 2 (design by analysis)
of the Code. These basic principles were published by ASME in
1968 under the title “Criteria of the ASME Boiler and Pressure
Vessel Code for Design by Analysis in Sections III and VIII, Division 2.” At the same time that the work of the Special Committee
to Review Code Stress Basis was nearing fruition, leaders in the
field of pressure vessel design, including Bernie Langer and Bill
Cooper, recognized that an improved forum for fundamental technical information exchange was needed. The need eventually led to
the formation of an ASME technical divi-sion, the Pressure Vessel
and Piping (PVP) Division, in 1966.
Many of us who became involved in the PVP Division in the
early years were drafted by the leaders in the field to help prepare
a compendium of the technical information on pressure vessel
and piping technology. The Decade of Progress volumes, as they
were known then, were published by ASME in the early 1970s,
covering the most significant contributions to pressure vessel
and piping design and analysis; materials and fabrication; and
operations, applications, and components. The Decade of Progress volumes should be considered the antecedents of these two
volumes. Both sets of volumes should be considered as integral
parts of the technical literature supporting the Code and the Criteria document.
The PVP Division has acted with great vigor over the years
to continue to provide the technical forums needed to support
improvements in the modern ASME Code. This year marks the
Division’s 35th anniversary. When I first became involved in PVP
Division activities, the second year had just been completed, with
Vito Salerno as the second Chair of the Division Executive Committee. Dana Young had been the first Chair, during 1966–1967,
and Gunther Eschenbrenner was ready to become the third Chair,
for the 1968–1969 year. Planning was well underway for the first
International Conference on Pressure Vessel Technology (ICPVT),
scheduled for Delft, the Netherlands, in the following year. The
plan was to hold such an international conference every four years,
with the Secretariat rotating between Europe (1969), the United
States (San Antonio, 1973), and Asia (Tokyo, 1977). Nine of these
international conferences have now been held, the most recent in
Sydney, Australia, in April 2000.
At the same time, initial planning for the First U.S. National
Congress on Pressure Vessels and Piping, to be held every four
years in the United States, was also underway. It was my privilege
to be the Technical Program Chair for the Second U.S. National
Congress on PVP in 1975 in San Francisco, and the Conference
Chair for the Third U.S. National Congress on PVP in 1979, also
in San Francisco. In addition, the activity within the PVP Division was such that we cosponsored ASME technical conferences
with the Materials Division, the Nuclear Engineering Division,
and the Petroleum Division in alternate years. This has since led
to the annual PVP Conference, the most recent being PVP 2001 in
Atlanta, Georgia, in July 2001.
The paper flow from the technical conferences and the network
of contributors for the Decade of Progress volumes eventually
led to the creation of the ASME Transactions Journal of Pressure
Vessel Technology in late 1973, only seven years after formation
of the Pressure Vessel and Piping Technical Division. Dr. Irwin
Berman was its first Senior Technical Editor, with two Technical
Editors representing the PVP Division and the Petroleum Division.
Once again, I consider it a privilege to have been selected as the
iv t Dedication
Technical Editor for the PVP Division, later becoming the Senior
Technical Editor in 1978. The Journal and the technical conferences have provided robust mechanisms for the needed technical
information exchange.
But ASME Code rules and the associated technical information
exchange is not enough. In one of the very early issues (November 1974) of the Journal of Pressure Vessel Technology, two articles were published on the duty and responsibility of engineers
and their engineering societies to address public concerns about the
safety and reliability of power plants. One, by Bernie Langer, was
titled “The Role of the Engineering Societies in Obtaining Public
Acceptance of Power Plants.” The other, by Bill Cooper, was titled
“Nuclear — Pressure Vessels and Piping — Materials: Where to
Next.” Both articles clearly identified the additional commitment
that we all share to bring sound information to the attention of the
general public and to policymakers in federal, state, and local jurisdictions. In the almost three decades since the publication of those
two articles, this commitment has been extended, as the reach of
ASME International, the ASME Boiler and Pressure Vessel Code,
and the PVP Division covers the entire world. We owe a debt of
gratitude to these two giants, and these two volumes represent a
“down payment” on that debt.
Robert E. Nickell, Ph.D.
1999–2000 President
William E. Cooper, Ph.D, P.E.
Dedication to the Fifth Edition
Since the initial first edition, this publication had not been dedicated;
for this edition both front and back cover pages have been revised to
show that this edition is considerably enlarged in coverage to reflect
the changing times and development in the Boiler & Pressure Vessel
Codes and Standards. Much the same, this fifth edition is dedicated
to two persons who have immensely influenced in my dedication to
this publication:
- Dr. K. Indira Rao had immense support since my first envisioning this project for the first edition and ever since for
each of the subsequent editions, for which she was gratefully acknowledged in each of the preceding four editions.
However, for her dedication to the cause of this publication,
as much as I have been and continue to be dedicated, I am
dedicating this edition, as well as saluting her for her continued enthusiasm which keeps me going.
- Late Dr. N. K. Jain, Founder and Executive VP, International
Society of Tea Science who was a close friend and an associate of mine, although from an entirely different field of expertise enthused me with his cross-Atlantic discussions about
the value of my participation and contribution. Dr. NK Jain’s
passing away in 2016 will cut short the intellectual discourses
and for its value and memory I dedicate this “classic” work,
which stimulates me to engage in similar challenging tasks.
K. R. Rao, Ph.D., P.E.
Editor
Acknowledgements to the
First Edition
The editor is indebted to several individuals and organizations in
the preparation of this two-volume book. Some of them are identified for their assistance in completion of this effort. My thanks are
to all of the thirty-nine contributors whose dedicated efforts made
this possible by their singular attention to detail, even while they
succinctly conveyed the voluminous information.
I wish to thank Dr. Jack Ware, Pressure Vessels and Piping Division who suggested this effort. My thanks are in particular to Martin
D. Bernstein who had from the start of this project been my inspiration to rally around during several ups and downs. I also thank Dr.
Robert E. Nickell for his encouragement to see the end of the tunnel.
This effort would not have been possible but for the encouragement and support provided by my employer, Entergy Operations
Inc., and in particular by Frederick W. Titus, William R. Campbell, John R. Hamilton, Willis F. Mashburn, Raymond S. Lewis,
Jaishanker S. Brihmadesam, Brian C. Gray, and Paul H. Nehrenz.
My special thanks to Professor Dr. Robert T. Norman, University of Pittsburgh, for the untiring pains he had taken in training me
to undertake efforts such as these — from their very initiation to
their logical conclusion.
This unique two-volume publication, which Dr. Frederick
Moody aptly called a “monumental effort,” would have never
taken off had it not been for the vision and sustained support provided by the staff of ASME Technical Publishing. My thanks to
them for their support.
Finally, all of this saga-type effort, spread over three years,
would have never been possible had it not been for the constant encouragement and untiring support provided by my wife,
Dr. Indira Rao, that included all of the sundry chores associated
with this project. In addition, I wish to thank other members of
my family, Uma and Sunder Sashti, and Dr. Ishu V. Rao, for their
zealous support.
Acknowledgements to the
Second Edition
This second edition following the success of the first edition has
an enlarged scope including the addition of a third volume. This
warranted the addition of several contributors who are all experts
in their respective specialties. The editor appreciates their contributions, as well as the continued support of the contributors from
the first edition.
Editor intends to once again thank Entergy Operations for their
continued support. Thanks are especially due to Dr. Indira Rao
whose support in several capacities made this voluminous effort
possible. My thanks are to the staff of ASME publishing for their
continued zeal and support.
Acknowledgements to the
Third Edition
This third edition follows the unprecedented success of the previous two editions.
As mentioned in the first edition, this effort was initiated with
the ‘end user’ in mind. Several individuals and a few organizations
had provided support ever since this effort started.
In the second edition the success of the first edition was enlarged
in scope with the addition of a third volume, with experts in their
respective specialties to contribute chapters they authored.
In response to the changing priorities of Boiler and Pressure
Vessel (B&PV) industry and global use of ASME B&PV Codes
and Standards the scope and extent of this edition has increased.
The result of the current effort is in a 2,550 page book spread in
three volumes.
The editor pays homage to the authors Yasuhide Asada, Martin
D. Bernstein, Toshiki Karasawa, Douglas B. Nickerson and Robert
F. Sammataro who passed away and whose expertise enriched the
chapters they authored in the previous editions.
This comprehensive Companion Guide with multiple editions
spanning over several years has several authors contributing to this
effort. The editor thanks authors who had contributed to the previous editions but did not participate in the current edition and they
are Tom Ahl, Domenic A. Canonico, Arthur E. Deardorff, Guy
H. Deboo, Jeffrey A. Gorman, Harold C. Graber, John Hechmer,
Stephen Hunt, Yoshinori Kajimura, Pao-Tsin Kuo, M. A. Malek,
Robert J. Masterson, Urey R. Miller, Kamran Mokhtarian, Dennis Rahoi, Frederick A. Simonen, John D. Stevenson, Stephen V.
Voorhees, John I. Woodworth and Lloyd W. Yoder.
The editor appreciates the effort of the continuing contributors
from the previous editions, who had a remarkable influence on
shaping this mammoth effort, few of them from the very beginning
to this stage. The editor gratefully acknowledges the following
authors Kenneth Balkey, Warren Bamford, Uma Bandyopadhyay,
Jon E. Batey, Charles Becht IV (Chuck), Sidney A. Bernsen,
Alain Bonnefoy, Marcus N. Bressler, Marvin L. Carpenter,
Edmund W. K. Chang, Kenneth C. Chang, Peter Conlisk, Joel
G. Feldstein, Richard E. Gimple, Jean-Marie Grandemange,
Timothy J. Greisbach, Ronald S. Hafner, Geoffrey M. Halley,
Peter J. Hanmore, Owen F. Hedden, Greg L. Hollinger, Robert I.
Jetter, Guido G. Karcher, William J. Koves, John T. Land, Donald
F. Landers, Hardayal S. Mehta, Richard A. Moen, Frederick J.
Moody, Alan Murray, David N. Nash, W. J. O’Donnell, David E.
Olson, Frances Osweiller, Thomas P. Pastor, Gerard Perraudin,
Bernard Pitrou, Mahendra D. Rana, Douglas K. Rodgers, Sampath
Ranganath, Roger F. Reedy, Wolf Reinhardt, Peter C. Riccardella,
Everett C. Rodabaugh, Robert J. Sims Jr., James E. Staffiera, Stanley
Staniszewski, Richard W. Swayne (Rick), Anibal L.Taboas, Elmar
Upitis and Nicholas C. Van Den Brekel.
Similarly the editor thanks the contribution of authors who
joined this effort in this third edition. Sincerity and dedication of
the authors who joined in this effort is evident from two instances
— in one case, a contributor hastened to complete his manuscript
before going for his appointment for heart surgery! In another
case, when I missed repeatedly a correction made by a contributor, he never failed to draw my attention to the corrections that I
missed!
Thus, the editor wishes to appreciate efforts of authors who joined
in this edition and worked zealously to contribute their best for the
completion of this ‘saga’. The authors are Joseph F. Artuso, Hansraj
G.Ashar, Peter Pal Babics, Paul Brinkhurst, Neil Broom, Robert G.
Brown, Milan Brumovsky, Anne Chaudouet, Shin Chang, Yi-Bin
Chen, Ting Chow, Howard H. Chung, Russell C. Cipolla, Carlos
Cueto-Felgueroso, K. B. Dixit, Malcolm Europa, John Fletcher,
Luc H. Geraets, Stephen Gosselin (Steve), Donald S. Griffin, Kunio
Hasegawa, Philip A. Henry, Ralph S. Hill III, Kaihwa Robert Hsu,
D. P. Jones, Toshio Isomura, Jong Chull Jo, Masahiko Kaneda,
Dieter Kreckel, Victor V. Kostarev, H. S. Kushwaha, Donald
Wayne Lewis, John R. Mac Kay, Rafael G. Mora, Dana Keith
Morton, Edwin A. Nordstrom, Dave A. Osage, Daniel Pappone,
Marty Parece, Michael A. Porter, Clay D. Rodery, Wesley C.
Rowley, Barry Scott, Kaisa Simola, K. P. Singh (Kris), Alexander V
Sudakov, Peter Trampus, K. K. Vaze, Reino Virolainen, Raymond
(Ray) A. West, Glenn A. White, Tony Williams.
The editor thanks Steve Brown of Entergy Operations for his
help in the search for expert contributors for this edition.
This edition was initiated by me in August 2006 and has taken
over 3000 hours of computer connection time. My thanks are
especially to my wife, Dr. Indira Rao whose sustained support for
this effort and participation in several chores related to editing.
In addition, I appreciate her tolerating my working on it during a
4-month overseas vacation.
The editor thanks the staff of ASME Technical Publications
for their unstinted zeal and support in aiming at this publication’s
target of ‘zero tolerance’ for ‘errors and omissions’.
Finally, the editor thanks all of you, readers and users of
this ‘Companion Guide’ and hopes it serves the purpose of this
publication.
Acknowledgements to the
Fourth Edition
This fourth edition follows the unprecedented success of the previous three editions.
As mentioned in the first edition, this effort was initiated with
the ‘end user’ in mind. Hundreds of individuals and several organizations had provided support ever since this effort started.
The success of the first two editions prompted us to enlarge the
scope with the addition of a third volume, with experts in the US
and around the world to contribute the chapters. In response to the
changing priorities of Boiler and Pressure Vessel (B&PV) industry
and global use of ASME B&PV Codes and Standards the scope
and extent of the third edition had vastly increased resulting in a
“mammoth” 2,550 page book spread in three volumes.
The editor in the “acknowledgements to the third edition” paid
homage to the authors Yasuhide Asada, Martin D. Bernstein,
Toshiki Karasawa, Douglas B. Nickerson and Robert F. Sammataro who passed away since the first edition and whose expertise
enriched the chapters they authored. Since then it is with profound
regret editor notes the passing away of Marcus N. Bressler and
Peter J. Conlisk who were not merely contributors to this “monumental effort” but were in several ways the “stanchions” of not only
the chapters they authored but ‘ardent advisors’ from the onset of
this effort to the time of their passing away.
This comprehensive Companion Guide spanning over several
years had several authors contributing to this effort. The editor
thanks authors who had contributed to the previous editions but did
not participate in the current edition and they are Edmund W. K.
Chang, Geoffrey M. Halley, Greg L. Hollinger, Donald F. Landers,
John T. Land, Hansraj Ashar, Barry Scott, Chuck Becht IV, Guido
G. Karcher and Richard E. Gimple. Most of these contributors had
been associated with this effort from the very beginning and to
them the editor salutes them for their signal contribution, direction
and continued support.
The editor appreciates the effort of the continuing contributors
from the previous editions, who had a remarkable influence on
shaping this mammoth effort, few of them from the very beginning to this stage. The editor gratefully acknowledges the follow-
ing authors John R. MacKay, Elmar Upitis, Richard A. Moen,
Marvin L. Carpenter, Roger F. Reedy, Richard W. Swayne (Rick),
David P. Jones, Uma S. Bandyopadhyay, Robert I. Jetter, Joseph
F. Artuso, Dana Keith Morton, Donald Wayne Lewis, Edwin A.
Nordstrom, Jon E. Batey, Thomas P. Pastor, Dave A. Osage, Clay
D. Rodery, Robert G. Brown, Philip A. Henry, Robert J. Sims Jr.,
Joel G. Feldstein, Owen F. Hedden, Russell C. Cipolla, James E.
Staffiera, Warren Bamford, Hardayal S. Mehta, Mahendra D. Rana
and Stanley Staniszewski.
Similarly the editor appreciates contribution of authors who
joined this effort in the current edition and worked zealously to
contribute their best for the completion of this ‘saga’. The authors
are James T. Pillow, John F. Grubb, Richard C. Sutherlin, Jeffrey
F. Henry, C.W. Rowley, Anne Chaudouet, Wesley C. Rowley, C.
Basavaraju, Jack R. Cole, Richard O. Vollmer, Robert E. Cornman
Jr., Guy A. Jolly, Clayton T. Smith, Arthur Curt Eberhardt, Michael
F. Hessheimer, Ola Jovall, James C. Sowinski, Bernard F. Shelley,
Jimmy E. Meyer, Joseph W. Frey, Michael J. Rosenfeld and Louis
E. Hayden Jr.
The editor thanks Jimmy E. Meyer for his help in the search for
topics and expert contributors for several B31 Piping Chapters for
this edition.
This edition was initiated by me in May 2011 and has taken just
over a year for completing this edition.
My thanks, as has been since I embarked on the first edition over
a decade back, are especially to my wife, Dr. Indira Rao whose
sustained support for this effort and participation in several chores
related to editing of this edition. In addition, I appreciate her tolerating my working on it during several vacations.
The editor thanks the staff of ASME Technical Publications for
their continued patience, undivided support and focused effort in
aiming once again at this publication’s target of ‘zero tolerance’
for ‘errors and omissions’.
Finally, the editor thanks all of you, readers and users of
this ‘Companion Guide’ and hopes it serves the purpose of this
publication.
Acknowledgements to the
Fifth Edition
This fourth edition continues the unprecedented success of the
previous four editions.
As mentioned in the first edition, this effort was initiated with
the “end user” in mind. Hundreds of individuals and several organizations had provided support ever since this effort started.
The success of the first two editions prompted us to enlarge the
scope with the addition of a third volume, with experts in the US
and around the world to contribute the chapters. In response to the
changing priorities of Boiler and Pressure Vessel (B&PV) industry
and global use of ASME B&PV Codes and Standards the scope
and extent of the third edition had vastly increased resulting in a
“mammoth” 2,550 page book spread in three volumes for the third
edition which prompted us to break the third edition into three
books. The fourth edition was strictly confined to “Companion
Guide to the ASME B&PV Code”. This fifth edition is an update
of the fourth edition to the 2015 Code Edition.
The editor in the “acknowledgements to the previous three editions” paid homage to the authors Yasuhide Asada, Martin D.
Bernstein, Toshiki Karasawa, Douglas B. Nickerson, Robert F.
Sammataro and John D. Stevenson who passed away since the first
edition and whose expertise enriched the chapters they authored.
Since then it was noted the passing away of Marcus N. Bressler
and Peter J. Conlisk who were not merely contributors to this
“monumental effort” but were in several ways the “stanchions” of
not only the chapters they authored but were ‘ardent advisors’ from
the onset of this effort to the time of their passing away.
This comprehensive Companion Guide spanning over several
years had several authors contributing to this effort. The editor
thanks authors who had contributed to the previous editions but did
not participate in the current edition and they are Edmund W. K.
Chang, Geoffrey M. Halley, Greg L. Hollinger, Donald F. Landers,
John T. Land, Hansraj Ashar, Barry Scott, Chuck Becht IV, Guido
G. Karcher, Richard E. Gimple, John R. Mackay, James T. Pillow,
Richard A. Moen, Marvin L. Carpenter, David P. Jones, Robert E.
Cornman, Jr., Joseph F. Artuso, Michael F. Hessheimer, Edwin
A. Nordstrom, Jon E. Batey, Robert G. Brown, Joel G. Feldstein,
Owen F. Hedden, Mahendra D. Rana, and Louis E. Hayden Jr.
Most of these contributors had been associated with this effort
from the very beginning and to them the editor salutes for their
signal contribution, direction and continued support.
The editor appreciates the effort of the continuing contributors
from the previous editions, who had a remarkable influence on
shaping this mammoth effort, few of them from the very beginning to this stage. The editor gratefully acknowledges following authors Elmar Upitis, Roger F. Reedy, Richard W. Swayne
(Rick), Uma S. Bandyopadhyay, Robert I. Jetter, Dana Keith
Morton, Donald Wayne Lewis, Thomas P. Pastor, Dave A. Osage,
Clay D. Rodery, Philip A. Henry, Robert J. Sims Jr., Russell C.
Cipolla, James E. Staffiera, Warren Bamford, Hardayal S. Mehta,
Stanley Staniszewski, Jimmy E. Meyer, John F. Grubb, Richard C.
Sutherlin, Jeffrey F. Henry, Anne Chaudouet, Wesley C. Rowley,
C. Basavaraju, Jack R. Cole, Richard O. Vollmer, Robert E. Cornman Jr., Guy A. Jolly, Clayton T. Smith, Arthur Curt Eberhardt,
Ola Jovall, James C. Sowinski, Bernard F. Shelley, Joseph W. Frey
and Michael J. Rosenfeld.
Similarly the editor appreciates contribution of authors who
joined this effort in the current edition and worked zealously to
contribute their best for the completion of this ‘saga’. The authors
are Ralph Hill III, Ed Ortman, Jay Vattappilly, William L. Lowry,
William Newell Jr., Mark A. Gray, Thomas M. Musto, Ross R.
Klein, Christopher A. Jones, G. Wayne Hembree, Charles Becht
V, John P. Swezy, Jr., Gary Park, Douglas Scarth, Kang Xu and
William K. Sowder.
This edition was initiated by me during the Atlanta Code Meeting
in November 2015 and has taken this long due to several factors for
completing this edition, including soliciting replacement and new
contributors as well as changes in Code Committee leaderships.
My thanks, as has been since I embarked on the first edition over
a decade back, are especially to my wife, Dr. Indira Rao whose
sustained support for this effort and participation in several chores
related to editing of this publication. In addition, I appreciate her
tolerating my working on it during several vacations.
The editor thanks the staff of ASME Technical Publications for
their continued patience, undivided support and focused effort in
aiming once again at this publication’s target of “zero tolerance” for
“errors and omissions.” Thus, worthy of recording are efforts of Mary
Grace Stefanchik and Tara Smith whose unbridled cooperation, support and advice have made this publication an “ASME Classic.”
Finally, the editor thanks all of you, readers and users of this Companion Guide and hopes it serves the purpose of this publication.
Contributor Biographies
AHL, THOMAS J.
Thomas J. Ahl earned a B.S.C.E. in 1960 and
M.S.C.E. in 1961 from University of Wisconsin.
He is a Registered Structural and Professional
Engineer in Illinois. He held the position of Principal Engineer in Nuclear & Pressure Vessel
Design Department, Chicago Bridge & Iron Co.,
Plainfield, IL, (1961–1998), and was engaged in
design and analysis of nuclear related vessels and structural components. Ahl was a Member of ANSI Working Group ANS-56.8
that prepared the ANSI/ANS-56.8-1981—Containment System
Leakage Testing Requirements standard.
Ahl is a Member of ASCE, Member of ASCE Hydropower
Development Committee, and Conventional Hydropower Subcommittee. He served as Co-Chair of the Task Committee preparing the publication “Manual of Practice for Steel Penstocks
ASCE Manual No. 79,” Vice-Chair-ASCE Committee preparing
the “Guidelines for Evaluating Aging Penstocks,” and member of ASCE Hydropower Committee preparing “Civil Engineering Guidelines for Planning and Design of Hydroelectric
Developments.”
Two of these publications received the ASCE Rickey Award
Medal in 1990 and 1994. Thomas Ahl is a member of the Peer
Review Group to Sandia National Laboratories and the U.S.
Nuclear Regulatory Structural Engineering Branch for the Safety
Margins for Containment’s Research Program, 1980–2001.
ARTUSO, JOSEPH F.
Joseph F. Artuso is the CEO of Construction Engineering Consultants, Inc. He has over 40 years
experience in developing and managing quality
control inspection and testing programs for construction materials. He is also actively involved in
the Code and Standards writing bodies of ACI and
ASME. Mr. Artuso earned a B.S. in Civil Engineering at Carnegie Institute of Technology in 1948 and became a
Level III Inspection Engineer at the National Council of Engineering Examiners in 1975. He is a registered Professional Engineer in
the states of Pennsylvania, Ohio, New York, Florida, Maryland and
West Virginia, as well as being registered as Quality Control Engineer in state of California. His memberships in national committees
include A.S.C.E. (Task committee on Inspection Agencies), A.C.I.
(Committees 214, 304 and 311), A.N.S.I. (N-45-3.5 Structural Concrete and Steel), A.S.M.E. (Committee 359 (ASME Sec. III, Div.
2) Construction Materials and Exam.), ACI-ASME (Committee
on Concrete Pressure Components for Nuclear Service), ASTM,
and NRMCA. He was a contributing editor of McGraw-Hill “Concrete Construction Handbook.” Mr. Artuso was the Director of Site
Quality Control for the Duquesne Light Company, Beaver Valley,
Unit 2. He also supervised construction quality control activities on
many nuclear power plants during the period of high construction
activity from the 1970’s to 1980’s.
ASHAR, HANSRAJ, G.
Mr. Ashar has a Master of Science degree in Civil
Engineering from the University of Michigan.
He has been working with the Nuclear Regulatory Commission for the last 35 years as a Sr.
Structural Engineer. Prior to that Mr. Ashar has
worked with a number of consultants in the U.S.
and Germany designing Bridges and Buildings.
Mr. Ashar has authored 30 papers related to structures in nuclear
power plants.
Mr. Ashar’s participation in National and International Standards Organization includes Membership of the NSO and INSO
Committees such as American Institute of Steel Construction
(AISC), Chairman of Nuclear Specification Committee (January
1996 to March 2008), (AISC/ANSI N690); Member of Building
Specification Committee, and Corresponding of Seismic Provisions Committee.
Mr. Ashar’s professional activities with The American Concrete Institute (ACI) 349 Committees include Member of the Main
committee, Subcommittee 1 on General Requirements, Materials
and QA, and Subcommittee 2 on Design. His professional activities also include American Society of Mechanical Engineers
(ASME), Corresponding Member, Working Group on Inservice
Inspection of Concrete and Steel Containments (Subsections
IWE and IWL of ASME Section XI Code), Member, ASME/ACI
Joint Committee on Design, Construction, Testing and Inspection of Concrete Containments and Pressure Vessels; Member,
RILEM Task Committee 160-MLN: Methodology for Life Prediction of Concrete Structures in Nuclear Power Plants; Member, Federation Internationale du Beton (FIB) Task Group 1.3:
Containment Structures, and Consultant to IAEA on Concrete
Containment Database (2001 to 2005).
Mr. Ashar is a Professional Engineer in the State of Ohio and
State of Maryland; Fellow, American Concrete Institute; Fellow,
American Society of Civil Engineers; Professional Meer – Posttensioning Institute. Mr. Ashar is a Peer Reviewer of the Papers to
be published in ASCE Material Journal, Nuclear Engineering and
Design (NED) Periodicals and ACI Material Journal.
x t Contributor Biographies
BAMFORD, WARREN
Warren Bamford has been a member of Section
XI since 1974, and now serves as Chairman of the
Subgroup on Evaluation Standards, whose charter
is to develop and maintain flaw evaluation procedures and acceptance criteria. He is a member
of the Executive Committee of Section XI, and
is a 2007 recipient of the ASME Bernard Langer
Award for excellence in Nuclear Codes and Standards. He is a Life Fellow of ASME, and has taught a course on the
Background and Technical Basis of the ASME Code, Section III
and Section XI, for over 30 years. Warren was educated at Virginia
Tech, Carnegie Mellon University, and the University of Pittsburgh.
Warren’s research interests include environmental fatigue crack
growth and stress corrosion cracking of pressure boundary materials, and he has been the lead investigator for two major programs
in this area. He was a charter member of the International Cooperative Group for Environmentally Assisted Cracking, which has been
functioning since 1977.
Warren Bamford has been employed by Westinghouse Electric
since 1972, and now serves as a Consulting Engineer. He specializes in applications of fracture mechanics to operating power plants,
with special interest in probabilistic applications. Over 85 technical
papers have been published in journals and conference proceedings.
BANDYOPADHYAY, UMA S.
Bandyopadhyay received his BSME from
Jadavpur University (1970), Calcutta, India,
MSME from the Polytechnic Institute of Brooklyn (School of Engineering, New York University) (1974). He is a registered Professional
Engineer in the states of New York, New Jersey,
Connecticut, Massachusetts, Virginia, Wyoming
and District of Columbia. He has 40 years of extensive experience in design, engineering and manufacturing of pipe supports
and pipe support products for Water Treatment and Waste Water
Treatment Facilities, Oil Refineries, Co-generation, Fossil and
Nuclear Power Plants. Bandyopadhyay is currently employed by
Carpenter and Paterson, Inc. as Chief Engineer and works as a
consultant and Registered Professional Engineer for affiliate BergenPower Pipe Supports, Inc. Prior to his current employment, he
held the positions of Design Engineer (1977–1980), Project Engineer (1980–1986) and Chief Engineer (1986–1992) with BergenPaterson Pipe support Corp. Bandyopadhyay is a member, ASME
B&PVC Section III, Working Group on Supports (Subsection NF),
since 1993; was an alternate member, Subsection NF (1986–1993).
He is also an alternate member, Manufacturer’s Standardization
Society (MSS), Committee 403-Pipe hangers (MSS-SP-58, 69, 89,
90 and 127) since 1992.
BASAVARAJU, CHAKRAPANI
Dr. Chakrapani Basavaraju, P.E., has over 30 years
of experience, which includes more than 28 years
in the power industry involving design of nuclear
and non-nuclear power plants, and 3 years in
the teaching profession. He received Ph.D. in
Mechanical Engineering from Texas A&M Uni-
versity. He is a registered Professional Engineer. He is a fellow of the
American Society of Mechanical Engineers (ASME).
He has been working as a Mechanical Engineer at the United States
Nuclear Regulatory Commission (USNRC) in the office of Nuclear
Reactor Regulation (NRR) since 2006. Previously, he worked Bechtel
Power Corporation, Stone & Webster Corporation, and Duke Power
Company. He has been recognized with several awards which include
Technical Specialist Award, Outstanding Technical Paper awards
(Bechtel 1993, 2005), and Instructor of the Year award for his exceptional achievements, contributions, and innovative solutions to practical engineering problems. Dr. Basavaraju has published 22 technical
papers, which are of value, and practical significance to the industry
and Engineering community on various topics in the areas of design
and analysis of power plant piping systems and components, Creep,
Fatigue, Flow Induced Vibration, Applications of Finite Element
Analysis, Extrusion, Weld shrinkage, and Hypervelocity Impact.
He contributed 3 chapters for internationally recognized reference handbooks. Technical papers written by him have broken new
grounds in providing innovative and cost effective approaches to
complex industry issues. He also has peer reviewed several technical papers. His in-depth knowledge of analytical methods, expertise in finite element analysis techniques, and extensive application
experience in applying those techniques for design and analysis
of power plant piping and mechanical components have earned
him the respect of his peers and superiors. He has chaired sessions
of the ASME Conferences and he is serving as a member of the
ASME PVP Design & Analysis Technical Committee.
Dr. Basavaraju has contributed chapters to the Piping Handbook
(6th Edition, 1992, & 7th Edition, 1999) and the Piping Databook
(6th Edition, 2002) published by McGraw-Hill, Inc. New York, NY.
In addition, he has reviewed sections of these two internationally
used reference books. His input, suggestions and contributions have
enriched the contents of these publications. Basavaraju provided
support and background information for code changes to ASCE 7
code, Tanks Seismic Group.
Technical Program Representative (TPR) for D&A Track of
ASME PVP/CREEP8 Conference (2007).
Dr. Basavaraju is a member of the PVP Design and Analysis
Technical Committee.
Serving as chair/vice chair at ASME PVP conference sessions
since 2002.
Basavaraju also chaired & co-chaired sessions for ASME
ICONE10 conference.
Member, ASME Section III B&PV Code, SC III SG-D, WGPD
(Working Group on Piping Design).
Member, ASME Section III B&PV Code, SC III SG-D, WGV
(Working Group on Vessels).
Member, ASME Section III B&PV Code, SC III, SWG (Special
Working Group on Plastic Piping).
BATEY, JON E.
Jon Batey is an ASME Fellow who has been a
member of ASME Standards Committee V since
1995 and has served as Chairman since 2002.
Jon has served on various sub-tier committees of
Standards Committee V since 1990 and currently
is a member of the Subgroup on Volumetric
Examination Methods, the Subgroup on General
Requirements, Personnel Qualifications and Interpretations, the
Working Group on Radiography, the Working Group on Acoustic
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t xi
Emission, and the Working Group on Guided Wave Ultrasonic
Examination. He is also a member of the ASME Post Construction Standards Committee and is Chairman of its Subcommittee
on Inspection Planning. Jon was also a member of the ASME B-16
Standards Committee from 1979 to 1993.
Jon is the Global Inspection Leader for The Dow Chemical
Company in Freeport, TX. In his current role, Jon is responsible
for inspection performed by Dow or third-party inspectors at supplier fabrication shops. He received a B.S. in Physics from Texas
State University. His certifications include NDT Level III in Radiography, Ultrasound, Liquid Penetrant, Magnetic Particle, Visual
and Leak Test Methods.
BECHT IV, CHARLES
Dr. Becht is a recognized authority in pressure
vessels, piping, expansion joints, and elevated
temperature design. He is President of Becht
Engineering Co. Inc, a consulting engineering
company providing services to the process and
power industries (www.becht.com, www.bechtns
.com for the nuclear services division, and www
.techtraining.info for technical training); President of Becht Engineering Canada Ltd.; President of Helidex, LLC (www.helidex
.com); and Director of Sonomatic Ltd. (also dba Becht Sonomatic,
www.vsonomatic.com) a NDE company that provides advanced
ultrasonic imaging. Chuck was previously with Energy Systems
Group, Rockwell International and Exxon Research and Engineering
where he was a pressure equipment specialist. He received a PhD
from Memorial University in Mechanical Engineering (dissertation:
Behavior of Bellows), a MS from Stanford University in Structural
Engineering and BSCE from Union College, New York. Chuck is a
licensed professional engineer in 16 states and provinces, an ASME
Fellow since 1996, recipient of the ASME Dedicated Service Award
in 2001, and has more than 60 publications including the book, Process Piping: The Complete Guide to ASME B31.3, and five patents.
Dr. Becht is Chair of the ASME B31.3, Process Piping Committee; Chair (founding) of the Post Construction Subcommittee on
Repair and Testing (PCC), and member of other ASME Committees
including the Post Construction Standards Committee (past Chair);
Post Construction Executive Committee (past Chair); B&PV Code
Subcommittee on Transport Tanks; B&PV Code Subgroup on Elevated Temperature Design (past Chair); B31 Code for Pressure Piping Standards Committee; B31 Mechanical Design Committee; B31
Executive Committee; and is a past member of the Board on Pressure Technology Codes and Standards; the B&PV Code Subcommittee on Design; and the B&PV Code TG on Class 1 Expansion
Joints for liquid metal service. He is a member of ASTM Committee
F-17, Plastic Piping Systems Main Committee; and the ASME PVP
Division, Design and Analysis Committee.
BECHT, CHARLES V.
Charles Becht V, is an experienced engineer familiar with both the application and the development
of the ASME BPVC Section VIII Divisions 1
thru 3. Specifically, Mr. Becht is a member of the
Working Group on Design under the Sub Committee SC VIII Div 3. Mr. Becht has participated in the
design of a number of vessels using the Division 3
basis, including fiber wrapped vessels. Mr. Becht has a Bachelors of
Science in Mechanical Engineering from Bucknell University, and a
Masters of Science in Nuclear Engineering from the Georgia Institute
of Technology.
BERNSTEIN, MARTIN D.
Mr. Bernstein was involved in the design and
analysis of steam power equipment since joining Foster Wheeler Energy Corporation in 1960.
Retired in 1996, he continued to serve as a consultant to Foster Wheeler and as their representative on the ASME Boiler and Pressure Vessel
Committee, on which he had served for more
than 25 years. He was Vice Chair, Subcommittee on Power Boilers, Chair, Subcommittee on Safety Valve Requirements, a member of the Main Committee (Standards Committee) and past Chair
of Subgroup General Requirements and the Subgroup Design of
the Subcommittee on Power Boilers. Since 1986 he and Lloyd
Yoder taught a two-day course on Power Boilers for the ASME
Professional Development Department. In 1998, ASME Press published Power Boilers—A Guide to Section I of the ASME Boiler
and Pressure Vessel Code that Bernstein and Yoder developed
from their course notes.
Mr. Bernstein was active for many years in ASME’s PVP Division. He was also author and editor of numerous ASME publications, including journal articles on ASME design criteria, ASME
rules for safety valves, flow-induced vibration in safety valve nozzles, and tubesheet design. Mr. Bernstein obtained a B.S. and M.S.
in civil engineering from the Columbia School of Engineering
and Applied Science. He was elected an ASME Fellow in 1992,
received the ASME Dedicated Service Award in 1994, and was
awarded the ASME J. Hall Taylor Medal in 1998. He was a Registered Professional Engineer in New York State. Mr. Bernstein
passed away in 2002.
BRESSLER, MARCUS N.
Mr. Bressler is President of M. N. BRESSLER,
PE, INC., an engineering consulting firm founded
in 1977, specializing in codes and standards,
quality assurance, design, fabrication, inspection and failure analysis for the piping, power,
petroleum and chemical industries. He has over
54 years of experience. He joined TVA in 1971 as
Principal Engineer and was promoted in 1979 to Senior Engineering Specialist, Codes Standards and Materials. He took early retirement in 1988 to open up a private consulting practice. His previous
experience was with the US Army (1952) where he served as an
Industrial Hygiene Engineer; the Babcock & Wilcox Company
(1955), where he held the positions of Engineering Draftsman,
Stress Analyst, and Boiler Division Materials Engineer; Gulf &
Western Lenape Forge Division (1966) where he became Senior
Design Engineer, and Taylor Forge Division (1970) as Product
Development Manager. At Lenape Forge he developed a design
for a quick-opening man way for pressure vessels and piping that
was granted a patent in 1971.
Mr. Bressler began his activities in Codes, Standards and Materials
in 1960. He has been a member of the ASME B&PV Standards Committee since 1979 to 2009, and is now a member of the Technical
xii t Contributor Biographies
Oversight Management Committee. He is a member and past Vice
Chair of the Committee on Nuclear Certification. He is a member of
the Standards Committees on Materials and on Nuclear Power, the
subgroup on Design (SCIII), the special working group on Editing
and Review (SC III), the Boards on Nuclear Codes and Standards
and on Conformity Assessment. He is the Chair of the Honors and
Awards Committee (BNCS). Mr. Bressler is a member of the ASTM
Committees A-01 and B-02 and many of their subcommittees.
Mr. Bressler holds a BME degree from Cornell University
(1952) and an MSME degree from Case Institute of Technology
(1960). In 1989 he received a Certificate of Achievement from
Cornell University for having pursued a course that, under today’s
requirements, would have resulted in a Master of Engineering
degree. He was awarded the ASME Century Medallion (1980),
and became a Fellow of ASME in 1983. He is now a Life Fellow.
He received the 1992 ASME Bernard F. Langer Nuclear Codes and
Standards Award and is the 1996 recipient of the ASME J. Hall
Taylor Medal. He received the 2001 ASME Dedicated Service
Award. He is a Registered Professional Engineer in the State of
Tennessee (Retired).
Mr. Marcus N. Bressler passed away since the publication of the
third edition.
BROWN, ROBERT G.
Mr. Brown is a Principal Engineer and Director of
Consulting for the Equity Engineering Group in
Shaker Heights, Ohio. He has experience as both
an owner-user and consultant providing engineering support to refineries and chemical plants
worldwide. Mr. Brown uses advanced skills in
Finite Element Analysis to provide practical
and cost effective solutions to solve design and operational issues
related to fixed equipment.
Mr. Brown assisted with the development of API 579 FitnessFor-Service and has been a consultant for the PVRC effort to
develop the new ASME, Section VIII, Division 2, Boiler and Pressure Vessel Code, taking into consideration the latest developments
in materials, design, fabrication, and inspection technologies.
Mr. Brown is an active member of the Battelle International
Joint Industry Project on the Structural Stress Method for Fatigue
Assessment of Welded Structures and performs fatigue assessments/reviews of equipment in cyclic service. Mr. Brown also
serves on the ASME Subgroup on Design Analysis and performs
code compliance calculations and interpretations for pressure vessels. Mr. Brown is a registered Professional Engineer in the States
of Ohio and Pennsylvania.
CANONICO, DOMENIC A.
Dr. Canonico received his B.S. from Michigan
Technological University, M.S. and Ph.D. from
Lehigh University. He has over 40 years experience in pressure parts manufacturing. Dr.
Canonico is currently employed by ALSTOM
POWER facilities in Chattanooga, Tennessee. He
is Past Chair of the ASME Boiler Pressure Vessel
(BPV) Code Main Committee and a member of the ASME Council
on C&S and Vice President-elect Pressure Technology, C&S. He is
a Fellow in ASME, the American Welding Society (AWS) and the
American Society for Metals (ASM). In 1999 Dr. Canonico received
the ASME Melvin R. Green C&S Medal. He was the 1994 recipient
of the ASME J. Hall Taylor Medal, in 1996 and 1999 respectively he
was awarded the Dedicated Service Award, and the ASME Region
XI Industry Executive Award. In 1978, 1979, and 1985 respectively
AWS awarded him the Dr. Rene Wasserman Award, the James F.
Lincoln Gold Medal, and the William H. Hobart Memorial Medal;
he was the 1983 Adams Lecturer. He is a member of the State of
Tennessee Boiler Rules Board.
He has written over 100 technical papers and given technical
talks in U.S., Canada, Mexico, Europe and Asia. He is named in
Who’s Who in Engineering and Men and Women of Science. Dr.
Canonico is an Adjunct Professor at the University of Tennessee,
Knoxville and on the Advisory Committee of the School of Engineering, University of Tennessee, Chattanooga.
CARPENTER, MARVIN L.
Marvin L. Carpenter graduated with honors from
Michigan Technological University (MTU) with
a B.S. in Metallurgical Engineering. Continuing
at MTU, he received his Masters in Metallurgical Engineering in 1974. Since graduating, his
career has been focused on welding fabrication
and testing in accordance with the ASME Boiler
and Pressure Vessel Code. ASME Code Committees first caught his attention in the late seventies and he has
remained active in the Code ever since. He served on the Standards
Committee on Welding, Brazing and Plastic Fusing (IX), Chaired
the Subgroup on Brazing (IX), Chaired the Subgroup on Materials (IX) and Chaired the Subgroup on Plastic Fusing. His major
accomplishment included the adoption of the rules for Plastic
Fusing as a Part of Section IX and the complete revision of the
P-Number tables. He is currently a Honorary member of Standards
Committee IX.
Mr. Carpenter gained expertise in production welding, brazing,
failure analysis, coatings, and material testing while working for
major corporations including Westinghouse Electric Corporation,
The Trane Company, and Bechtel Corporation. His experience
ranges from supervising a Welding Engineering Develop group to
establishing and operating a materials testing laboratory that performed chemical analysis, mechanical testing, metallography, and
welding procedure and performance qualification.
In addition to his extensive materials and welding background,
he was granted a patent in 1995 for a GTAW-HW circular welding system. He worked extensively for providers of power plant
equipment and retired in 2014 from his Principal Engineer position
with Bechtel Corporation. Mr. Carpenter has two children, Scott
and Michelle, and currently resides in Punta Gorda, FL with his
wife, Denise.
CHANG, EDMUND W. K.
Edmund W.K. Chang, P.E., received his BSME
from the University of Hawaii (UHM), 1969.
Mr. Chang is currently employed as the Boiler &
Welding Maintenance Engineer with Hawaiian
Electric Company, Inc., Power Supply Engineering Department, Honolulu, Hawaii. Mr. Chang’s
responsibilities include being in-charge of all
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t xiii
company boiler condition assessments, and National Board (NB)
“R” and “VR” Symbol Stamp repair programs. Mr. Chang is also
a NB commissioned O/U Inspector, in charge of in-service and
acceptance inspections. He is a AWS Certified Welding Inspector
(CWI), in charge of welding program, and the company’s NDT
Level III in PT and MT in charge of the NDT program.
Mr. Chang’s professional affiliations include ASME Membership since 1971; association with ASME Hawaii Section as Chairman 2008–2009, Honors & Awards Committee Chair, Webmaster,
Newsletter Editor, and Section Chair 1993–1994; ASNT Hawaii
Section Director and Webmaster; AWS Hawaii Section Webmaster; and Chair 1996 of Hawaii Council of Engineering Societies.
Mr. Chang is a member of the Department of Mechanical Engineering, UHM, Industry Advisory Board.
Mr. Chang’s professional publications include as a lead author
of “T91 Secondary Superheater Tube Failures Investigation,” 1997,
ASME PVP Conference, Orlando, Florida; and “Tangential-Fired
Boiler Tube Failures, A Case Study,” 2007, EPRI International Conference on Boiler & HRSG Tube Failures, Calgary, Alberta, Canada.
CHAUDOUET, ANNE
Ms. Chaudouet earned a Master of Pure Maths at
Paris XIII University in 1974 and then obtained
a Mechanical Engineering Degree from ENSMP
(Mines) in Paris-France in 1976. The same year,
she started her career at Cetim (French Technical
Centre of Mechanical Industries) in R&D in the
field of solid mechanics analysed by the Boundary Element Method (BEM).
Soon after, she became in charge of the team responsible for
the development of all software developed at Cetim in the domain
of 2D and 3D heat transfer and solid mechanics. In that role she
had the direct responsibility for the analyses of components by
BEM and for fracture mechanics. In 1984, she became head of the
Long Term Research Service involved in more theoretical studies
and development of design rules for pressure vessels. In the same
year she initiated Cetim’s participation in PVRC (Pressure Vessel
Research Council). She is now retired and working as a consultant
in the domain of pressure equipment.
Since 2003, Ms. Chaudouet has been actively involved in ASME
Boiler and Pressure Vessel Code organization where she is now
a member of the Board on Pressure Technology Codes & Standards and of the Technical Oversight Management Committee. At a
more technical level she is a member of the Standard Committee on
Materials, of SG II/International Material Specifications (currently
Chair of this SG), of the Standard Committee on Pressure Vessels,
and of SG VIII/Heat Transfer Equipment. She is also an active
member of the ASME/API Joint Committee on Fitness for Service.
In France, Ms. Chaudouet is a member of AFIAP (French Association of Pressure Equipment Engineers). She has been a member
of the Liaison Committee dealing with the European Directive on
Pressure Equipment and of the Liaison Committee dealing with the
French Order on Nuclear Pressure Equipment.
Ms. Chaudouet has published over 30 papers in French and in
English in the domain of Boundary Elements, Fracture Mechanics and more recently on Fitness-For-Service. Most of these were
presented at International Conferences. Member of several PhD
theses, she has developed professional courses on these topics. In
the domain of pressure equipment she has also given short courses
on the European Directive (PED).
CIPOLLA, RUSSELL C.
Mr. Russell Cipolla is a Principal Engineer for
Intertek AIM, Santa Clara, California (USA). He
has been very active in ASME Code Section XI
since joining the Working Group on Flaw Evaluation in 1975, for which he is currently Chairman. He is also a member of the Working Group
on Pipe Flaw Evaluation, Subgroup on Evaluation Standards, and Standards Committee on Nuclear Inservice
Inspection. He has participated in many ad hoc committees as well
on such topics as environmental fatigue methods, stress corrosion
cracking of austenitic materials, crack growth and fracture toughness reference curves for pressure vessels and piping, and steam
generator tube examination and evaluation procedures. He has also
given workshop/tutorials on the technical basis and application of
the ASME Section XI flaw evaluation procedures.
Mr. Cipolla received his B.S. degree in Mechanical Engineering from Northeastern University and his M.S. in Mechanical
Engineering from Massachusetts Institute of Technology. He has
been active in the Nuclear Power Industry since the early 1970s
having worked at the nuclear divisions of Dynatech, Babcock &
Wilcox, and General Electric companies in the area of ASME
Section III design evaluations for both naval and commercial
power plants systems. Mr. Cipolla has authored/coauthored over
80 technical papers on various subjects and assessments from his
past work.
Mr. Cipolla has specialized in stress analysis and fatigue and
fracture mechanics evaluations of power plant components in
operating plants. He has applied his skills to many service problems to include stress corrosion cracking in reactor system components and steam turbine rotors/blades, mechanical and thermal
fatigue in power piping, and fitness-for-service of components
and supports. He was also involved in resolving the US NRC
Generic Safety Issues A-11 and A-12 regarding fracture toughness and bolted joint integrity. He is well versed in the integrity of threaded fasteners for both structural joints and pressure
boundary closures.
In recent years, he has been active in probabilistic methods and
acceptance criteria for nuclear steam generators regarding pressure
boundary integrity in compliance with NEI 97-06 requirements.
In support of industry group efforts, he has made significant contributions to the EPRI Steam Generator Management Program for
the assessment of tube integrity and leakage performance for various degradation mechanisms affecting Alloy 600 and 690 tubing
materials. He has developed methods for predicting tube burst and
leak rates under various service conditions, which have become
an integral part of the integrity assessment guidelines for steam
generators.
COLE, JACK R.
Jack Cole is a Senior Advisory Engineer for
Becht Engineering Nuclear Services Division
and he is an ASME Fellow. Mr. Cole has over
forty years of experience in the nuclear power
industry, including nuclear waste management,
nuclear plant construction, and 30 years in commercial nuclear power plant design and operation. Prior to joining Becht Engineering, Mr. Cole worked 30 years
for Energy Northwest, the operator of the Columbia Generating
xiv t Contributor Biographies
Station BWR. At Energy Northwest, Mr. Cole served as the Design
Authority responsible for plant Civil/Structural/Stress licensing
basis compliance. Mr. Cole’s work activities have included design
of pressure vessels and piping systems, development of ASME
Design Specifications for pressure components, operability assessments for degraded components, repair and replacement activities
for mechanical components, plant vibration and thermal fatigue
monitoring and support for major projects such as plant power
uprate, pump and valve replacement, replacement of the plant condenser and heaters, and time limited aging evaluations for license
renewal. Mr. Cole has served as technical consultant to IAEA in
the area of aging management for mechanical components for plant
life extension and is an instructor for courses in ASME Section III
Code Design, Piping Design, and Fitness for Service.
Mr. Cole retired from active Codes as Standards participation
after serving for 32 years on various ASME Section III committees. He is past Vice Chairman of the BPV Committee on
Construction of Nuclear Facility Components (BPV III), past
Chairman of the BPV III Executive Committee on Strategy and
Project Management, past Chairman of the Special Committee
on Interpretations (BPV III), past Member of the Subgroup on
Component Design (BPV III), past Member and Chairman of
the Working Group on Piping, and past member of the Working
Group on Supports (III).
Mr. Cole has a B.S. degree in Mechanical Engineering from
Oregon State University (1972) with additional graduate studies at the University of Washington and Washington State University. Mr. Cole is a Registered Professional Engineer. He has
published several papers on piping fatigue analysis and vibration
assessment.
CONLISK, PETER J.
Dr. Conlisk’s has a B.S. in Mechanical Engineering and M.S. in Engineering Science from the University of Notre Dame and Ph.D. in Engineering
Mechanics from the University of Michigan. He
has forty years experience applying engineering
principles, computers, experimental techniques,
and Codes and Standards to solving design of processing equipment and vessels in the chemical industry. From 1960
until 1968, he worked in the Aerospace industry and from 1968 until
his early retirement in 1993, Dr. Conlisk worked for the Monsanto
Corporation, the last 19 years in the Engineering Department. He
was a key member in a team at Monsanto that developed acoustic
emission examination for fiberglass and metal tanks and vessels. His
services are now available through Conlisk Engineering Mechanics,
Inc., a consulting firm he formed in 1994. He has concentrated on
design of tanks and pressure vessel, especially fiberglass composite
(FRP) vessels. Dr. Conlisk is a nationally recognized authority in
FRP equipment design and analysis. He is a member of the ASME
committee that developed the ASME/ANSI Standard: “Reinforced
Thermosetting Plastic Corrosion Resistant Equipment, RTP-1.”
Dr. Conlisk is past chairman and current vice-chairman of the
ASME B&PV Code subcommittee, Section X, governing FRP
pressure vessels. He is also a past member of the main committee
of the ASME B&PV Code. Dr. Conlisk is a registered professional
engineer in Missouri.
Dr. Peter J. Conlisk passed away since the publication of the
third edition.
CORNMAN, E. ROBERT JR.
Bob Cornman is a Director of Product Engineering for the Flow Solutions Group of the Flowserve
Corporation. He holds a BS degree in Civil Engineering from Lehigh University and an MBA from
Lehigh University. Bob Cornman is a Registered
Professional Engineer in the State of Pennsylvania.
He is an active ASME member and has been chairman of ASME Nuclear Section III Working Group on Pumps for
many years.
Bob Cornman’s engineering career spans more than 40 years
all of which has been spent working for Flowserve or its legacy
companies in the design and manufacturing of centrifugal pumps.
His primary areas of expertise are in the design, application, and
manufacturing of very large vertical single pumps and vertical
multi-stage can pumps. He has authored numerous papers on vertical pump design, applications, and other associated equipment.
Past projects and work experience has involved major fossil and
nuclear power generating stations, large drainage and flood control
projects, and pump manufacturing test facilities.
DEARDORFF, ARTHUR F.
Arthur F. Deardorff has a Mechanical Engineering B.S., from Oregon State University (1964) and
MS, University of Arizona (1966). He is a Registered Mechanical Engineer, State of California. He
is a Vice President, Structural Integrity Associates,
San Jose, California. His professional experience
includes 1987 to present with Structural Integrity
Associates, San Jose, CA, 1976–1987 with NUTECH, San Jose,
CA, 1970–1976 with General Atomic Company, San Diego, CA
and 1966–1970 with The Boeing Company, Seattle, WA. His professional associations include American Society of Mechanical Engineers and American Nuclear Society. He is a Past Member of the
ASME Code Section XI Subgroup Water Cooled Systems, Working
Group on Implementation of Risk-Based Inspection, Task Group
on Erosion-Corrosion Acceptance Criteria, Task Group on Fatigue
in Operating Plants, and Task Group on Operating Plant Fatigue
Assessment, and the ASME Code Post Construction Committee,
Subgroup on Crack-Like Flaws.
Mr. Deardorff has expertise in fracture mechanics, stress analysis and reactor systems evaluation, with a strong academic background in thermal-hydraulics and fluid system. His expertise
includes PWR and BWR systems and fossil-fired power plants.
Art is known internationally for providing ASME Code training
in Section III design and analysis and Section XI flaw evaluation.
EBERHARDT, ARTHUR CURT
Dr. Eberhardt has a Bachelor of Architectural
Engineering from Iowa State University. Ames,
IA and a Ph.D. from the University of Illinois at
Urbana, IL. He is a Registered Structural Engineer in the State of Illinois and a Registered
Professional Engineer in the States of Texas and
Illinois. Dr. Eberhardt is a Senior Consultant at Sargent & Lundy,
LLC in Chicago, Illinois, where he has worked for over 40 years on
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t xv
projects involving nuclear plant design and analysis. Dr. Eberhardt
has gained a wide variety of structural engineering experience in
many areas including containment design, dry spent fuel storage
structures, seismic analysis, blast analysis, plant modifications,
heavy loads analysis, design criteria development, design basis
reconstitution, configuration baseline documentation, high-density
spent fuel pool analysis, structural maintenance rule evaluations,
and 10 CFR 50.59 safety evaluations. He has worked on projects
associated with more than 14 nuclear power plants.
Dr. Eberhardt has served on ASME BP&V Code Committees for
more than 23 years. He is past Chair of the Joint ACI/ASME Committee on Concrete Components for Nuclear Service (also known
as ACI Committee 359), which is responsible for the ASME Section III, Division 2 Code for Concrete Containments. He is also
a member of the ASME Section III Committee on Construction
of Nuclear Facility Components and contributing member of the
ASME Board on Nuclear Codes and Standards.
FELDSTEIN, JOEL G.
Joel Feldstein has a Metallurgical Engineering
B.S. (1967) and M.S. (1969) from Brooklyn Polytechnic Institute. He has more than 30 years’ experience in the welding field ranging from welding
research for a filler metal manufacturer to welding
engineering in the aerospace and power generation
industries. He began his career in power generation
with Babcock & Wilcox in 1972 at their R&D Division working on
manufacturing-related projects and moved into plant manufacturing
in 1984 as the Manager of Welding. There he became familiar with
the construction of components for both nuclear and fossil applications. His first assignment on coming to Foster Wheeler in 1993 was
in the Technical Center as Manager of Metallurgical Services later
taking on the additional responsibility of the Welding Laboratory.
In 1998 he assumed the responsibility of Chief Welding Engineer.
Joel, who is currently Chairman of the ASME BPV Code Technical Oversight Management Committee, a member of the Board
on Pressure Technology Codes & Standards and the Council on
Standards & Certification, began his ASME Code involvement
with the Subcommittee on Welding (the responsible committee for
Section IX) in 1986. In 1992 he became Chairman of the Subcommittee on Welding and became a member of the B&PVC Standards Committee. He is an ASME Fellow and recipient of the J Hall
Taylor Medal from ASME for the advancement of standards for
welding in pressure vessel and piping construction. He is also been
a member of the BPV Committee on Power Boilers (Section I).
He is also active in other professional societies including AWS
and the Welding Research Council where he served as Chairman
of the Stainless Steel Subcommittee, the High Alloys Committee
and a member of their Board of Directors.
FREY, JOSEPH W.
Joe Frey has a BSME from Louisiana Tech University (1980) and is a Registered Professional
Engineer in the state of Texas. He is past Chair
of the ASME B31.1 Power Piping Code Committee and has been a member of that committee since 1992. Joe is a recipient of the B31.1
Master of Power Piping Award for his work on developing Chapter VII Operation and Maintenance. He has focused mainly on
the fabrication, erection, examination, and maintenance of power
piping. He is also a member of the B31 Main Committee and several sub committees. Joe is a consulting engineer and the Power
Practice Lead at Stress Engineering Services, Inc. (SES) in Houston, Texas. Joe has spent 35 years developing fitness for service
programs for piping systems. Part of his work is the emergency
repair of piping and pressure vessels. Since joining SES, in 2004
Joe has worked several more emergency repairs, including twenty
four fire damage assessments and two coal silo cone weld failures.
GIMPLE, RICHARD E.
Richard Gimple has a BSME from Kansas State
University (1974) and is a Registered Professional
Engineer. Since 1982 he has been employed by
the Wolf Creek Nuclear Operating Corporation.
Previous employment was with Sauder Custom
Fabrication (1979–1982) and Fluor Engineers
and Constructors (1974–1979).
As a nuclear utility employee, he has primarily been involved in
implementation of ASME’s Boiler & Pressure Vessel Code Section III and Section XI during construction and operation activities.
Previous non-nuclear experience involved Section VIII pressure
vessel and heat exchanger design and construction. At present, as
a Principal Engineer, Mr. Gimple provides company wide assistance in the use of ASME Codes, with emphasis on Section III and
Section XI.
Mr. Gimple has been active in the Codes and Standards development process since 1984. Mr. Gimple was the 2005 recipient
of the ASME Bernard F. Langer Nuclear Codes and Standards
Award. He is currently a member of the B&PV Standards Committee (since 2000), the Subcommittee on Inservice Inspection of
Nuclear Power Plant Components (since 1994, serving 5 years as
Chairman of Subcommittee XI during 2000–2004), the Section XI
Executive Committee (since 1992), and the Subgroup on Repair/
Replacement Activities (since 1987, serving as Chairman for 7 of
those years). Past Codes and Standards participation included 6
years on the Board on Nuclear Codes and Standards and memberships on the Subcommittee on Nuclear Accreditation, Subgroup
on Design (in Section III), and three Section XI Working Groups.
GRABER, HAROLD C.
Harold Graber works as an Independent Consultant. Previously he was with the Babcock Wilcox
Company in the Nuclear Equipment Division for
34 years. He was Manager of NDT Operations and
Manager of Quality Assurance Engineering. Harold
Graber is a Member of ASME for 15 years.
He is an active participant on the B&PV Code,
Subcommittee V on Nondestructive Examination. He was Vice
Chair Subcommittee V; Chair, Subgroup on Surface Examination.
He was Member of Subcommittee V on Nondestructive Examination, Subgroup of Volumetric Examination, Subgroup on Personnel Qualification and Inquiries.
Harold Graber is a Member, American Society for Testing Materials (ASTM) for 26 years. He was Chairman, Subcommittee E7.01
xvi t Contributor Biographies
on Radiology. His Committee memberships include Committee E-7
on Nondestructive Examination, Subcommittee E7.02—Reference
Radiological Images, Subcommittee E7.06—Ultrasonic Method.
He is a Member, American Society for Nondestructive Testing
(ASNT). He is a Past Chair, Cleveland, Ohio Section—1971.
Harold Graber is the recipient of ASTM Merit Fellow Award
(1992); ASTM Committee E-7—C.W Briggs Award (1989);
ASNT Fellow Award (1978). His Certifications include ASNT;
Level III certificates in Radiography, Ultrasonic, Liquid Penetrant
and Magnetic Particle Methods.
GRAY, MARK R.
Mark Gray is a Fellow Engineer at Westinghouse
Electric Company near Pittsburgh, Pennsylvania.
He has worked for Westinghouse since 1981 in
areas related to design, analysis, and management
of nuclear power plant components and piping
systems. His work activities have included piping
stress and fatigue analyses, structural evaluations
to support license renewal, and development of
solutions to industry issues such as surge line stratification, thermal
stratification and cycling, pressurizer insurge/outsurge transients,
and reactor water environmental effects on fatigue. His responsibilities also include the development of diagnostic and monitoring
system software and its plant specific applications for fatigue and
transient monitoring. Related to these activities, he has also contributed significantly to the development of fatigue aging management solutions, led Westinghouse Owners’ Group programs, and
participated in EPRI’s Fatigue Issues Task Group and Environmental Fatigue Expert Panel. He has worked on numerous environmental fatigue projects for plant specific and generic industry
evaluations.
Mr. Gray is a member of the ASME Section III Working Group
on Piping Design and the Working Group on Environmental
Fatigue Evaluation Methods. He has co-authored over twenty conference papers or journal articles, and numerous industry reports.
His degrees from the University of Pittsburgh include Bachelors
and Masters Degrees in Mechanical Engineering and a Nuclear
Engineering certificate. He is a Registered Professional Engineer.
GRUBB, JOHN F.
Dr. Grubb received his B.S. from Lehigh University, M.S. and Ph.D. from Rensselaer Polytechnic
Institute. He has over 40 years’ experience with
corrosion-resistant alloys. His primary areas of
expertise are in mate- rials environmental resistance, behavior and applications. He is the author
of more than 50 papers as well as several handbook chapters. Dr. Grubb is currently retired from ATI Flat Rolled
Products (Allegheny Ludlum). He is co-inventor of several patented
corrosion-resistant alloys.
Dr. Grubb has been active with the ASME Boiler and Pressure Vessel Committees since 2001 and is the current vice chair
of BPV II (Materials) and chairman of the ASME Sub-Group on
Physical Properties for Section BPV II as well as chairman of the
ASME SubWorking-Group on Materials Data Analysis for Section
VIII BPV II. He is also an active member of the Sub-Groups on
External Pressure, Ferrous Specifications, and Non-Ferrous Alloys
(all BPV II). Dr. Grubb is a Fellow of ASM International (the former American Society for Metals). He is active in ASTM where he
has revised several materials and testing specifications and chairman of ASTM’s Wrought Stainless Steels subcommittee.
HALLEY, GEOFFREY M.
Geoffrey M. Halley, P.E. holds degrees in Electrical Engineering, Mechanical Engineering, and
Engineering Administration (Masters). He is a Registered Professional Engineer in Illinois. From
1993 to the present he is the President of Sji Consultants, Inc., a technical consulting company,
providing services to the boiler industry in the
areas of product design, development, trouble shooting and forensic investigation/expert witness work. He has 40 years of boiler
industry experience, ranging from research/product development,
design and applications/installation, primarily in the institutional
and industrial segments of the marketplace. He held various positions at Kewanee Boiler Corporation from 1968 to 1986, initially as
Supervisor of Research and Development, and as Vice President –
Technical Director from 1979 onwards. From 1986 through 1992
he was president of Halcam Associates a Mechanical Contracting
Company specializing in commercial, institutional and industrial
design/build/service and repair of boiler and HVAC systems. From
1959 through 1968 he was employed in the Aerospace and the
Nuclear Engineering industries.
Geoffrey Halley was Chair of ABMA Joint Technical Committee (1981–1986), and has been a member of several boiler industry
advisory groups to the USEPA and USDOE. He currently is ABMA
Director of Technical Affairs, and was Editor of ABMA Packaged
Boiler Engineering Manual. He has been an Instructor at boiler
industry technician training schools offered by ABMA/NBBI,
and boiler manufacturers. He has authored a number of papers on
boiler related topics, published in The National Board Bulletin,
Boiler Systems Engineering, and Maintenance Management.
Geoffrey Halley currently is a member of the ASME CSD-1
Committee, and the National Board Inspection Code Sub-committee
on Installation.
HAYDEN JR., LOUIS E.
Louis Hayden has over 40 years of experience as
a mechanical engineer, project manager and vice
president of engineering. This experience has
been in the design, analysis, fabrication, installation, startup and maintenance of industrial
piping and equipment systems have included
above and below ground piping and pipelines
in process plants, fossil and nuclear power plants, transmission
pipelines and industrial manufacturing facilities. He has managed
and directed the manufacturer of high yield pipeline pipe fittings
and developed new pipeline closure and flange products as well
as managed the efforts of new product development and research
groups.
Currently a consulting mechanical engineer and adjunct professor of mechanical engineering at Lafayette College, Easton, PA.
Previous employers have been Fluor Corp., Houston; Brown &
Root Inc., Houston; Tube Turns, Inc., Louisville; Victaulic Corp.,
Easton, PA.
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t xvii
Member of ASME B31 Piping Standards Committee since 1985.
Vice Chair ASME B31 Piping Standards Committee 1990–1993
and 2001–2004.
Chairman ASME B31 Piping Standards Committee 1993–2001.
Member ASME Board on Pressure Technology Codes and
Standards 1993–2005.
Vice President of ASME Board on Pressure Technology Codes
and Standards 2008–2011.
Vice Chair ASME Board on Pressure Technology Codes and
Standards 2005–2008.
Chairman ASME Task Group for development of B31.12
Hydrogen Piping and Pipeline Code.
Member Board on Pressure Technology Codes and Standards
Materials for Hydrogen Service Task Group.
HECHMER, JOHN
Mr. John Hechmer has a degree in I Mechanical
Engineering from the University I of Notre Dame
(1957). He joined the I Babcock & Wilcox Co.
(now owned by I McDermott, Inc.) for design
and analysis I work for pressure vessels. His
work was I primarily for the power generation
and I defense industries. His experience included
project and engineering management, technology development,
and management. His Power Generation products were for both
BWR and PWR nuclear electric plants. Defense Industries work
addressed Class 1 pressure vessels for the nuclear navy program,
primarily nuclear reactors and steam generators for aircraft carriers and submarines. Research products included Breeder Reactor
Program, Sodium-steam Generator, Molten Salt Steam Generator.
Technology Development was spent in developing tools and procedures for design-analysis interfacing with the Research Center
and Engineering Fabrication of Babcock & Wilcox Co. This was
enhanced by many years of participation in ASME B&PV Committees, PVRC, and PV&P Conferences. These engineering efforts
occurred for 40 years.
Mr. John Hechmer has more than 25 publications, addressing
primary and secondary stress evaluation, stress intensity factors,
finite element methods and its applications, brittle fracture, welding capability for fatigue, and material’s characteristic, examples
of this are PVRC Bulletins #429 (3D Stress Criteria Guidelines
For Application) and #432 (Fatigue-Strength-Reduction Factors
for Welds Based on NDE).
HEDDEN, OWEN F.
Owen F. Hedden retired from ABB Combustion
Engineering in 1994 after over 25 years of ASME
B&PV Committee activities with company support. His responsibilities included reactor vessel
specifications, safety codes and standards, and
interpretation of the B&PV Code and other industry standards. He Continued working part-time for
that organization into 2002. Subsequently, he has been a part-time
consultant to the ITER project and several other organizations.
Prior to joining ABB he was with Foster Wheeler Corporation
(1956–1967), Naval Nuclear program. Since 1968 Mr. Hedden has
been active in the Section XI Code Committee, Secretary (1976–
1978), Chair (1991–2000). In addition to Section XI, Owen has
been a member of the ASME C&S Board on Nuclear Codes and
Standards, the Boiler and Pressure Vessel Committee, and B&PV
Subcommittees on Power Boilers, Design, and Nondestructive
Examination. He is active in ASME’s PVP Division. Mr Hedden
was the first Chair of the NDE Engineering Division 1982–1984.
He has presented ASME Code short courses in the US and overseas. He was educated at Antioch College and Massachusetts Institute of Technology.
His publications are in the ASME Journal of Pressure Vessel
Technology, WRC Bulletins and in the Proceedings of ASME PVP,
ICONE, IIW, ASM, and SPIE. He is an ASME Fellow (1985),
received the Dedicated Service Award (1991), and the ASME Bernard F. Langer Nuclear Codes and Standards Award in 1994.
HEMBREE, G. W.
G. Wayne Hembree has nearly 50 continuous years
of experience in the field of Nondestructive Examination (NDE). He began his career after attending
the DOE (Department of Energy) intensive nine
month Physical Testing curriculum of TAT (Training and Technology), held at the Y-12 facility of
Union Carbide in Oak Ridge Tennessee (1967). He
was employed by an NDE service company prior to his induction
into the U. S. Army (1969) where he continued performing NDE on
military aircraft during the early Vietnam era.
Upon discharge, he was employed by a piping fabricator in South
Carolina (1971) prior to joining Combustion Engineering (C-E) in
1972 at their nuclear facility in Chattanooga, Tennessee. His first
Level III by examination was acquired in 1972 when he became the
Chief NDE Level III Evaluator over the fabrication/manufacture of
nuclear components. In 1976, he transferred to C-E’s Construction Services organization at their Windsor, Connecticut facility.
He departed C-E in 1987 after performing as Manager of NDE
Services over worldwide NDE operations. He immediately began
employment with TVA (Tennessee Valley Authority) and retired
after 27 plus years of government service in the power industry in
2013. He oversaw the successful NDE completion of three SGR’s
(steam generator replacements) as TVA’s Principal Level III. Mr.
Hembree is one of a few that has Manufacturing, Construction and
Utility experience in the NDE power generation industry.
Mr. Hembree has recently performed as Adjunct Professor at
Chattanooga State Community College (CSCC) teaching NDE as
part of CSCC Associate NDE degree program. He is the owner of
Industrial Image Interpretation & Consulting Inc. specializing in
ASME Code compliant images and ASME Code consulting services. He is twice elected as Chairman of Standards Committee V,
Nondestructive Examination, a member of Technical Oversight
and Management Committee (TOMC) and a member of numerous
working groups and subgroups. He has been an ASME Code committee member for nearly forty years.
HENRY, JEFFREY F.
Jeff Henry currently works as a Senior Associate at
Structural Integrity Associates, Inc. and formerly
was Director of ALSTOM Power Inc.’s Materials
Technology Center in Chattanooga, TN. His professional experience has been concentrated on the
service performance of power plant materials, with
xviii t Contributor Biographies
particular focus on high temperature behavior, welding, and the Creep
Strength-Enhanced Ferritic Steels, such as Grade 91. He has authored
over 60 technical papers. Mr. Henry is an ASME Fellow and is active
on a number of the ASME Boiler & Pressure Vessel Code technical
committees where he chairs BPV II, the Materials Standards Committee, as well as the Task Group on Creep Strength-Enhanced Ferritic Steels. He also is a member of BPV I (Power Boilers) and of the
Management Oversight Technical Committee (TOMC).
HENRY, PHILIP A.
Mr. Henry, Principal Engineer for the Equity
Engineering Group in Shaker Heights, Ohio, is
a specialist in the design, installation, sizing and
selection of pressure relief devices and relieving systems. He is currently chairman of the API
Pressure Relieving System Subcommittee’s Task
Force on RP 520 related to the design and installation of pressure relieving systems. He conducts audits of pressure
relieving systems to ensure compliance with OSHA PSM legislation and ASME, API and DIERs standards, codes and publications.
He also teaches the official API Pressure Relieving Systems course.
Mr. Henry is actively involved in the development of technology for the API Risk-Based Inspection (RBI) methodology. He
is co-author of the re-write of API 581, Risked-Based Inspection
Base Resource Document and is responsible for the development and implementation of Risk-Based Inspection programs for
pressure relief valves and heat exchanger bundles at refining and
petrochemical plants. He also teaches the official API 580/581
Risk-Based Inspection course.
Mr. Henry provides technical support and engineering consulting
to all levels of refinery capital projects. He has been responsible for
the preparation of purchase specifications, bid tabulations, design
reviews and the development and validation of approved vendors
lists. He conducts project safety reviews for construction and prestartup phases of major capital projects. His responsibilities include
developing and maintaining engineering specifications in the pressure relief and heat transfer areas and providing overall coordination.
Mr. Henry is a registered Professional Engineer in the States of
Ohio and Texas.
HESSHEIMER, MICHAEL F.
Mike Hessheimer is currently the Manager for
Mechanical Environments testing in the Engineering Sciences Center’s Validation and Qualification Sciences Experimental Complex at
Sandia National Laboratories in Albuquerque,
New Mexico. Prior to his current assignment,
he managed the Nuclear Power Plant Security
Assessment programs conducted for the US Nuclear Regulatory
Commission and was the Project Manager and Principal Investigator
for the Cooperative Containment Research Project, jointly funded
by the Nuclear Power Engineering Corporation of Japan and the US
NRC. His technical expertise is focused on the response of structures (with a special emphasis on containment vessels) subjected
to extreme loads due to natural, accident and hostile events and is
the author of numerous reports and papers on this subject. Prior to
his employment at Sandia National Laboratories, Mr. Hessheimer
was a consultant in private practice and was also employed by BDM
International, Morrison-Knudsen Co. Inc. and Sargent and Lundy
Engineers where he worked on the design and analysis of nuclear
containment structures. Mr. Hessheimer received his Bachelor and
Master of Science degrees in Structural and Civil Engineering from
Michigan Technological University. He is a Registered Professional
Engineer in New Mexico. He is also a member of the American
Society of Civil Engineers, the American Concrete Institute and the
American Society of Mechanical Engineers. He is a member and
past chair of the ACI/ASME Joint Committee on Concrete Components for Nuclear Service (ASME Boiler and Pressure Vessel Code
Section III, Division 2 Code for Concrete Containments.
HILL III, RALPH S.
Mr. Ralph S. Hill III retired from Westinghouse
Electric Company at the end of August 2014
and formed his own consulting company, Hill
Eng Solutions LLC. Mr. Hill has over forty
years of technical and management experience
including more than eighteen years in planning,
engineering design, construction, and modification for the nuclear power industry. Prior to
retirement, he was a Westinghouse Electric Company Consulting Engineer for Nuclear Services. In the fourteen years prior to
Westinghouse, he provided strategic planning, system engineering, risk management, process evaluation, and project management consulting services to U.S. Department of Energy in spent
nuclear fuel, radioactive waste management, and nuclear materials disposition-related projects. Mr. Hill has extensive experience in project management, systems engineering, and systems
analysis for high-level and low-level waste and nuclear materials
disposition systems.
Mr. Hill has been actively involved as a contributor and a leader
in promulgation of ASME nuclear codes and standards for over
35 years and has been awarded the Codes and Standards Distinguished Service Award. Currently, he Chairs the ASME Board on
Nuclear Codes and Standards and the Boiler and Pressure Vessel
Code, Standards Committee for Construction of Nuclear Facility
Components (Section III). Mr. Hill is past-Chair of the ASME
Subgroup on Component Design, and serves as member and/or
chair on numerous other nuclear code committees. He is actively
involved in bringing risk-informed probabilistic design methods
into the ASME Code as well as initiatives to support both advanced
and next-generation nuclear reactors.
HOLLINGER, GREG L.
Greg L. Hollinger is a Senior Principal Engineer
for BWX Technologies, Inc. in Barberton, Ohio.
He has responsibility for Mechanical/Structural
Technology Applications and Design Analysis of
Navy Nuclear Pressure Vessel Components and
use of the ASME Boiler & Pressure Vessel Code.
He chairs the Engineering Department’s Technical
Support Team responsible for developing technology procedures.
He is involved with both nuclear and non-nuclear ASME Certificates of Authorization for BWXT’s Nuclear Equipment Division.
Greg is a Fellow Member of ASME, and was the 2004 recipient
of the ASME Pressure Vessels and Piping Medal. He is the Chairman of the Subgroup on Design Analysis of the Sub-committee on
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t xix
Design of the ASME Boiler and Pressure Vessel Code. Greg is a
member of the Pressure Vessel Research Council (PVRC) and the
International Council on Pressure Vessel Technology (ICPVT). He
has served on several Boards within the ASME Council on Codes
and Standards, and he served as Chair of the ASME Pressure Vessels and Piping Division in 1995.
Greg is an Registered Professional Engineer (Ohio) with 30 years
of engineering practice in power-related industries.
JETTER, ROBERT I.
Mr. Jetter has over 50 years experience in the
design and structural evaluation of nuclear components and systems for elevated temperature
service. He was a contributor to the original
ASME Code Cases eventually leading to Subsection NH. For over 25 years he chaired the
Subgroup on Elevated Temperature Design (SGETD). He is currently a member of the Committee on Construction of Nuclear Facility Components (BPV-III), the Subcommittee
on Design, Subgroup on High Temperature Reactors, SG-ETD
and Working Groups – High Temperature Gas Cooled Reactors,
High Temperature Liquid Cooled Reactors, Analysis Methods,
Creep-Fatigue and Negligible Creep, and Elevated Temperature
Construction. Mr. Jetter was a member of a Department of Energy
(DOE) steering committee responsible for elevated temperature
design criteria, and was a consultant and reviewer on various DOE
projects. As a long time employee of Rockwell/Atomics International, he participated in and directed design activities as first
and second level manager on the early sodium cooled reactors
and space power plants through all the US LMFBR programs. He
currently consults on the development and application of elevated
temperature design criteria. He was an International Fellow for the
Power Reactor and Nuclear Fuel Development Corporation at the
Monju Fast Breeder Reactor site in Japan and co-authored the text
“Design and Analysis of ASME Boiler and Pressure Vessel Components in the Creep Range.”
He is a Fellow of the ASME and received its Dedicated Service
Award in 2011.
JOLLY, GUY A.
Guy A. Jolly is a consultant engineer for Samshin
Limited of South Korea for ASME Codes and
Standards issues. Guy Jolly retired as Chief Engineer of Flowserve/Vogt Valve in 2001. He holds
a BS degree in Mechanical Engineering from
the University of Kentucky and a MA degree in
Mathematics from the University of Louisville.
He is a Registered Professional Engineer in the
State of Kentucky with reciprocity capabilities. Guy Jolly is active
on the American Society of Mechanical Engineers (ASME) B16,
B31 and Section III Code and Standards Committees. He served
on both the American Petroleum Institute Refining (API) and
the Manufacturing Standardization Society of the Valve and Fitting Industry (MSS) standards writing committees for more than
30 years. He is a past president of MSS. He is an ASME Fellow
and received the ASME Dedicated Service Award in 2008. He is a
current member of ASME B16 Subcommittees C, N, F, MTC and
the B16 Standards Committee. He is the past Vice Chair of ASME
B16 Standards Committee and currently serves as Vice Chair of
B16 SC-N, Valve Committee. He is a past Chair of ASME B16
Subcommittee F for fittings. He is active in the flange, valve,
fitting and material committees of B16. In 2017 he received the
ASME B16 Hall of Fame Medal for lifetime exemplary service
and leadership to ASME B16 Committees. He is a Member of
ASME B31.5, B31.12, B31MTC, and B31 Piping Standard Committees. He is a past Chair of the Honors and Award Committee for
both ASME B16 and B31 Standards Committees. He also serves
on the ASME Nuclear Section III Working Group on Valves. He
has served as a USA expert of industrial valves at International
Organization for Standardization (ISO) conferences in the USA,
Yugoslavia, England, France, Italy and the Netherlands.
Guy Jolly’s engineering career spans more than fifty years. He
has made significant contributions to the piping industry while
an employee of a NASA Contractor and a large manufacturer of
valves and fittings. While at Chrysler Space Division in Huntsville,
AL he was the Project Engineer for developing and qualifying a
multi-shape piping standard for high-pressure liquid hydrogen
fuel systems that was published for use in space vehicles’ piping systems. While with Chrysler Space Division he was a representative on the “Marshall Center Zero Leakage Committee”
with a goal to reduce leakage from piping and components aboard
space vehicles. Mr. Jolly’s accomplishments include the establishment and management of a Nuclear Products Group for the Henry
Vogt Machine Co., which manufactured “N” stamp valves for
the nuclear power industry. He has published a number of papers
including those dealing with “leakage fluid mechanics” and “fugitive emission issues.” Guy A. Jolly, Colonel, USAR, Retired, is a
retired 30-year veteran of the Army Reserve Program. His military
education included the Air War College and the Command and
General Staff College.
JONES, CHRISTOPHER A.
Christopher A. Jones is presently a principal
member of the technical staff at Sandia National
Laboratories where he leads the Nuclear Power
Reactor Containment Integrity Research program within Sandia’s Nuclear Energy and Fuel
Cycle Programs Center. Dr. Jones has technical expertise in the areas of computational
mechanics, particularly for transient dynamics
to include blast and impact loading, beyond design basis internal pressurization loading, as well as aging and degradation of
cement-based materials. Funded primarily by the United States
Nuclear Regulatory Commission, he has authored a number of
publications on the subject of containment analysis. In addition
to containment related research, he supports the United States
Department of Energy in the risk-based launch safety assessment
for nuclear powered space missions and in the verification and
validation for reactor simulation codes as a part of the Consortium
for the Advanced Simulation of Light Water Reactors. Dr. Jones
serves as a member of several professional committees including: the ASME BPVC Section III Division 2/ACI 359 committee for Design of Concrete Containments for Nuclear Structures
as well as ACI 349: Concrete Nuclear Structures, and ACI 236:
Materials Science of Concrete. Dr. Jones holds a Ph.D., M.S., and
B.S. in Civil Engineering from Texas A&M University where
he researched novel experimental characterization techniques for
cement-based materials.
xx t Contributor Biographies
JONES, DAVID P.
Dr. Jones has 40 years experience in structural
design analysis and is lead consultant and developer on structural design procedures for SDB63 (Structural Design Basis, Bureau of Ships,
Navy Dept., Washington, D.C.). Dr. Jones is an
expert on brittle fracture, fatigue crack growth,
fatigue crack initiation, elastic and elastic-plastic
finite element methods, elastic and elastic-plastic perforated plate
methods, limit load technology, linear and non-linear computational methods and computer applications for structural mechanics. Dr. Jones’s key contributions have been developing computer
programs that allow use of complex three-dimensional finite element stress and strain results for the evaluation of ASME structural
design stress limits. He introduced numerical methods to compute
fatigue usage factors, fatigue crack growth, brittle fracture design
margins and the like that have now become standards for use in
naval nuclear design. He is currently working on using finite element elastic-plastic analysis tools for evaluation of limit load,
fatigue, shakedown, and ratchet failure modes.
Dr. Jones has been an active contributor to the ASME Boiler and
Pressure Vessel Code Committees; secretary and member of Subgroup on Fatigue strength, Member and chairman of the Subgroup
on Design Analysis, Chairman of the Subcommittee on Design,
and Chairman of the Task Force on Elastic-Plastic FEA. Dr. Jones
was Chairman of Metal Properties Council Task Force on Fatigue
Crack Growth Technology. He has also served as Associate Editor of the ASME Journal of Pressure Vessels and Piping. He has
published over thirty papers on the topics of fatigue, fatigue crack
growth, fracture mechanics, perforated plate technology, computational structural mechanics methods, non-linear structural
analysis methods, finite element code development for fracture
mechanics applications, finite element applications for perforated plate analysis (elastic and elastic-plastic), post-processing
finite element results for ASME Boiler and Pressure Vessel Code
Section III assessment, limit load technology, and elastic-plastic
fracture mechanics. He has been awarded ASME PVP Literature
Award – Outstanding Survey Paper of 1992 in ASME Journal
of Pressure Vessels and Piping and ASME PVPD Conference
Award – Outstanding Technical Paper form Codes & Standards –
July 26, 2000. Dr. Jones received his BS and MS degrees from the
University of Toledo in 1967 and 1968 and his PhD from Carnegie
Mellon University in 1972. Dr. Jones is a Fellow of ASME and has
worked at the Bettis Atomic Power Laboratory in West Mifflin,
Pennsylvania since 1968 where he currently holds the position of
Consultant Engineer.
JOVALL, OLA
Ola Jovall has a Master of Science degree in Civil
Engineering from Chalmers University of Technology, Gothenburg, Sweden. He is an Associate and Senior Expert of Scanscot Technology
AB, Lund, Sweden. His professional experience
includes more than 25 years working in the field
of Structural Design Engineering. Mr. Jovall has
during his profession been involved in structural
investigations of 9 of the 12 reactor containment units present in
Sweden. Since 2004 he is involved in Nuclear Power Plant (NPP)
New Built projects in Scandinavia, including the third reactor
at Olkiluoto, Finland, now under construction. His engagement
has mainly been related to issues regarding the reactor containment structure. During the years, Mr. Jovall has also been heavily involved in developing design requirements and guidelines for
design of safety-related Civil structures at NPPs including reactor
containments. He is Co-Author of a NPP Swedish Industry Standard for concrete design in force at the NPP units in Sweden. He
is on the behalf of the Swedish Radiation Safety Authority the
Main Author of the document “Guidelines for the design of concrete containments and other concrete safety-related structures at
NPPs” (in Swedish) published 2012. Mr. Jovall is a current member of various ASME Section III and ACI committees regarding
design, construction, testing and inspection of concrete containments and concrete nuclear structures including Joint ACI-ASME
Committee on Concrete Components for Nuclear Service (ASME
Sect III Div 2/ACI 359), Working Group on Modernization (Vice
Chair), Working Group on Design, ACI Committee 349 Concrete
Nuclear Structures, and ACI 349 and ACI 359 Joint Committee
Task Group.
KARCHER, GUIDO G.
Guido G. Karcher, P.E. is a consulting engineer
with over 48 years of experience in the mechanical engineering aspects of pressure containing
equipment. He retired from the Exxon Research
and Engineering Co. after serving 30 years as
an internationally recognized engineering advisor on pressure vessel, heat exchangers, piping and tankage design, construction and maintenance. On retire
from Exxon Research & Engineering Co. in 1994; he became a
Consulting Engineer on fixed equipment for the petrochemical
industry and related industry codes and standards. Guido has also
functioned as the Technical Director of the Pressure Vessel Manufactures Association, for 15 years, in the areas of mass produced
pressure vessel construction and inspection requirements.
Guido’s code activities include over 35 years of participation
in ASME, PVRC and API Codes and Standards activities serving
on numerous committees and technical development task groups.
He was elected to the position of Chairman of the ASME Boiler
& Pressure Vessel Standards Committee for two terms of office
(2001–2007) and was elected to the office of Vice President Pressure Technology Codes and Standards (2005–2008). Guido also
served as Chairman of the Pressure Vessel Research Council and
the American Petroleum Institute Subcommittee on Pressure Vessels and Tanks. He has written numerous technical papers on subjects related to pressure containing equipment.
Guido is an ASME Life Fellow and a recipient of the J. Hall
Taylor Medal for outstanding contributions in the development
of ASME Pressure Technology Codes and Standards. Guido
was also recently awarded the 2007 Melvin R. Green Codes and
Standards Medal for outstanding contributions to the development
and promulgation of ASME Codes and Standards within the USA
and Internationally. Other awards include the API Resolution of
Appreciation and Honorary Emeritus Membership of Pressure
Vessel Research Council. He earned a B.S.M.E. from Pratt Institute and M.S.M.E. from Rensselaer Polytechnic Institute and is a
registered Professional Engineer in the States of New York and
New Jersey.
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t xxi
KLEIN, ROSS R.
Ross R. Klein is the manager of the Stress & Thermal Analysis and Materials Engineering group for
Curtiss-Wright Corporation in Cheswick, PA. He
has more than twenty years of experience in the
design and analysis of pressure vessels and bolted
closures along with hands-on experience operating main propulsion plants in the U.S. Navy. He
is a licensed Professional Engineer in the Commonwealth of Pennsylvania.
Mr. Klein holds B.S. and M.S. degrees in Mechanical Engineering from the Swanson School of Engineering at the University of
Pittsburgh, and an M.B.A. from the Katz Graduate School of Business. He is currently the Chairman of the ASME Section III Working Group on Pumps.
Design and Subgroup on Design. He continues as a member of these
Section III groups as well as Subcommittee III and also served as a
member of section XI and the BPVC Standards Committee.
Mr. Landers also served as a member of the Board on Nuclear
Codes and Standards and as Vice Chairman. He has served on
PVRC committees and was heavily involved in the PVRC research
that led to the new seismic design rules in Section III.
He is an internationally recognized expert in piping design and
analysis and application of ASME Code and regulatory requirements. Mr. Landers has authored over 20 technical papers related
to design and analysis of pressure components.
He is currently involved in providing consulting services to the
utility industry in the areas of Life Extension, Code compliance,
and Operability issues. Don continues to provide training and
seminars on Code Criteria and application internationally. He is
recipient of the Bernard F. Langer Award, J. Hall Taylor Award,
and ASME Dedicated Service Award.
LAND, JOHN T.
John T. Land, P.E., has been involved in the
design, analyses and manufacturing of Westinghouse’s PWR nuclear primary equipment products for almost thirty years. His product design
experience includes reactor internals, steam generators, pressurizers, valves, and heat exchangers. Mr. Land also contributed to the design and
development of the AP600 and AP1000 MWe Advanced Power
Plants, the Westinghouse/Mitsubishi APWR 4500 MWt Reactor
Internals, and many of the currently operating Westinghouse PWR
domestic and international reactor internals components. In addition, he has directed and reviewed the design and analysis efforts
of engineers from Italy (FIAT and ANSALDO), Spain (ENSA),
Czech Republic, and Japan (MHI) on several collaborative Westinghouse international efforts. His experience included five years
with Westinghouse as a stress analyst on nuclear valves in support of the Navy’s Nuclear Reactor Program. Prior to working
for Westinghouse, Mr. Land spent eleven years with the General
Electric Company on the design and development of Cruise Fan
and XV-5A Vertical Take-Off and Landing aircraft propulsion
systems. He also holds eleven patents from General Electric, and
Westinghouse. Mr. Land received his BS in Mechanical Engineering from Drexel University and his MS in Applied Mechanics from
the University of Cincinnati.
Over the past thirty years, John has been active in ASME B&PV
Code work. Mr. Land is currently member of the Working Group
Core Support Structures and participates in the rule making and maintenance of Sub-Section NG. John is also a member of Sub-Group
Design that oversees Section III and Section VIII Design Rules.
LANDERS, DONALD F.
Donald F. Landers, P.E., is currently Chief Engineer of Landers and Associates. He was General
Manager and President of Teledyne Engineering
Services where he was employed from 1961 to
1999. Mr. Landers, an ASME Fellow, has been
involved in ASME Code activities since 1965
serving as a Member of B31.7 and Chairman of
their Task Group on Design, Section III Working Group on Piping
LEWIS, DONALD W.
Mr. Donald Wayne Lewis is the Director of Waste
Management for Westinghouse Electric Company with over 36 years of experience in commercial nuclear power and Department of Energy
(DOE) nuclear related projects. His experience
is on Mechanical/Structural engineering projects
including spent fuel management, nuclear power
system design, NRC licensing and MOX fuel fabrication facility
design.
He has spent 26 years in his primary area of expertise which is
related to dry spent nuclear fuel storage and is currently Project
Director for several Independent Spent Fuel Storage Installation
(ISFSI) projects. He has also served as a design reviewer for the
DOE Yucca Mountain Project concerning spent fuel processing
and disposal.
Mr. Lewis is a Member of the ASME Subgroup on Containment
Systems for Spent Fuel and High-Level Waste Transport Packagings. He is the author of five publications related to spent fuel
storage which are in the 2003, 2005 and 2013 proceedings of the
International Conference on Environmental Remediation and Radioactive Waste Management (ICEM) and 2015 and 2016 proceedings
of the Waste Management Conference; all sponsored by ASME.
Mr. Lewis received a B.S. in Civil Engineering from Montana
State University in 1980. He is a Registered Professional Engineer
in New York, Ohio, Maine, Iowa, Utah and Colorado.
LOWRY, WILLIAM
Mr. Lowry has served as a member of ASME Code
Committees for 43 years. Currently he is an Honorary Member of Section I-Power Boilers Code
Committee following 30 years as a member of that
Committee.
He received a BS in Mechanical Engineering
from the University of Illinois in 1961 and a Masters of Business
Administration from the University of Oklahoma City in 1982.
He has held Professional Engineering licensees in four states. He
taught the ASME Short Course on Section I-Power Boilers in 2014
through 2016.
xxii t Contributor Biographies
In 2012 Mr. Lowry was selected by ASME to lead the editing of
Section VII-Recommended Guidelines for the Care and Operation
of Power Boilers. The editing of Section VII included requested
input from 10 current and past Code members as well as responding to 29 peer reviewers. This effort led to the 2015 Edition as
accepted by Section I-Power Boilers Committee.
During his career, Mr. Lowry participated and directed the
mechanical design, construction, startup, revision and upgrading
of steam and electric generation for municipal, industrial, utility
and government entities. This work included steam and gas turbines fueled with gas, oil, coal and nuclear.
MACKAY, JOHN R.
Mr. John Mackay has over 50 years experience
as a mechanical engineering specialist in boilers,
pressure vessels, steam accumulators, ASME
Code construction, Nondestructive examination,
heat transfer systems, combustion and municipal
incinerator design and construction. John has a
Bachelor of Engineering (Mech.), 1951 from
McGill University, Montreal and followed it by numerous courses
over the years in Management, Management Techniques, and
Post-graduate engineering and management courses at Concordia
University.
Mr. John Mackay was an employee of Dominion Bridge
Company Limited in Montreal from 1951 to 1984 and has since
continued to work as a private consultant in his field. His major
accomplishments of the hundreds of projects he has been involved
include the Primary System Feeder Pipes for the CANDU nuclear
reactors, boilers for waste/refuse mass burn disposal systems and
design and maintenance of API Storage Tanks. John has extensive
experience in the design and construction of heat recovery boilers for the metallurgical industry. John is recognized as one of the
leading practitioners of his specialties in Canada.
Mr. John Mackay has been a member of ASME for over
40 years, during which he has served on a variety of committees
engaged in updating existing Codes, introduction of new Codes,
and the investigation and resolution of questions referred to these
committees. He has been a member of Section I Power Boiler
Subcommittee since 1968 to present time, Chaired it 1989–2004;
Member Standards Committee, 1971–present; Subgroup Electric
Boilers (SCI) and chaired it in 1978–84; Member & Chairman
Adhoc Task group on Acceptance Criteria. John was a Member
and Chair of the Section V Subcommittee on Nondestructive
Examination; Joint Task group B31.1/SCI. John is a member
of Subgroup on General requirements & Surface Examination
(SCV); and is a member of Subgroup on Materials (SCI). John
was a member of Honors & Awards Committee (B&PV) from
1989–2006, and chaired in 1995–2006. He was a Member Executive Committee (B&PV Main Committee) from 1992–2004. In
addition to ASME John is affiliated with several professional
organizations including Engineering Institute of Canada and Quebec Order of Engineers.
John Mackay has several publications and has given lectures on
engineering topics both in Canada and USA. John was a participant
of several PVP conferences and ASHRAE. He has several hobbies
that include Contract Bridge and John is happily married with adult
children.
MALEK, M. A.
M. A. Malek is a Professional Engineer (P.E.) registered in the state of Maine, P. Eng. Canada registered in the Province of I New Brunswick and
Prince Edward Island. Mohammad is a Certified
Plant Engineer, CPE, U.S.A., and has more than
27 years experience in boiler and pressure vessel
technology. Presently he is the Chief Boiler Inspector for the state of Florida.
Mr. Malek has demonstrated leadership in B&PV boiler and
pressure vessel industry. His achievements include developing
and designing a special husk-fired, fire-tube boiler of capacity
500 lbs/hr at 50 psi for developing countries. He has vast knowledge and experience in writing, and enforcing boiler and pressure
vessel laws, rules, and regulations. He has written numerous articles and published in several technical journals. Malek obtained
his BSME degree from Bangladesh Engineering and Technology,
Dhaka (1972) and MBA from Institute of Business Administration,
University of Dhaka (1979).
Malek has been a member of ASME since 1980 and Fellow of
Institution of Engineers, Bangladesh. He is an instructor of ASME
Professional Development courses, and serves on three ASME
Committees including CSD-1 Committee, QFO-1 Committee, and
Conference Committee of the ASME B&PV Committee. Malek
has been a member of the National Board of Boiler and Pressure
Vessel Inspectors since 1997.
MASTERSON, ROBERT J.
Masterson has a BSME from University of Rhode
Island (1969) and course work for MSME, University of Rhode Island (1973). He is a Registered
Professional Engineer in states of RI, MA, IL,
NE, MI and AK, and is currently self-employed
at RJM Associates in Fall River, MA. Masterson
is a retired Captain, U.S. Army Corp of Engineers
(1986). His professional experience included New England Electric
System (1969–1970), ITT Grinnell Corporation, Pipe Hanger
Division, Providence, RI (1972–1979). With ITT Grinnell he was
a Manager of Piping and Structural Analysis for the Pipe Hanger
Division (1974) and developed stress analysis, and testing for
ASME Section III Subsection NF and provided training in Subsection NF for ITT Grinnell, several Utilities, AEs and support for
NRC Audit. In 1978 he became Manager Research, Development
and Engineering. He was Manager of Engineering (1979) at Engineering Analysis Services, Inc. East Greenwich RI later in 1990
called EAS Energy Services. He was Vice President of Operations
(1984) and tasks included NRC audit support, turnkey projects and
valve qualification.
Masterson was an alternate member, Working Group on Component Supports (Subsection NF), 1973–1979; Member Subsection NF 1979 to the present. Chaired Task Groups for Subsection
NF jurisdiction; Chair of Working Group on Supports (SG-D)
(SC III) since May, 2000 and Member of Committee for the First
Symposium on Inservice Testing of Pumps and Valves, 1989,
Washington, DC, NUREG/CP-0111.
Prior to his present position, he was Chief Boiler, Elevator and
Tramway Inspector for the state of Maine, Deputy Chief Inspector
of state of Louisiana and Chief Boiler Inspector, Bangladesh.
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t xxiii
MEHTA, HARDAYAL S.
Dr. Mehta received his B.S. in Mechanical Engineering from Jodhpur University (India), M.S. and
Ph.D. from University of California, Berkeley. He
was elected an ASME Fellow in 1999 and is a
Registered Professional Engineer in the State of
California.
Dr. Mehta has been with GE Nuclear Division (now, GE-Hitachi Nuclear Energy) since 1978 and currently holds the position of Chief Consulting Engineer. He has
over 40 years of experience in the areas of stress analysis, linearelastic and elastic-plastic fracture mechanics, residual stress
evaluation, and ASME Code related analyses pertaining to BWR
components. He has also participated as principal investigator
or project-manager for several BWRVIP, BWROG and EPRI
sponsored programs at GE, including the Large Diameter Piping
Crack Assessment, IHSI, Carbon Steel Environmental Fatigue
Rules, RPV Upper Shelf margin Assessment and Shroud Integrity Assessment. He is the author/coauthor of over 50 ASME
Journal/Volume papers. Prior to joining GE, he was with Impell
Corporation where he directed various piping and structural
analyses.
For more than 25 years, Dr. Mehta has been an active member
of the Section XI Subgroup on Evaluation Standards and associated working an task groups. He is also a member of Section
III Working Group on Core Support Structures. He also has been
active for many years in ASME’s PVP Division as a member
of the Material & Fabrication and Codes & Standards Committees and as conference volume editor and session developer. His
professional participation also included several committees of
the PVRC, specially the Steering Committee on Cyclic Life and
Environmental Effects in Nuclear Applications. He had a key role
in the development of environmental fatigue initiation rules that
are currently under consideration for adoption by various ASME
Code Groups.
MEYER, JIMMY E.
Jimmy Meyer has over 40 years’ experience in
refining petrochemical, chemical, power generation and industrial facilities. He is a principal engineer at Louis Perry Group a CDM Smith Company,
a full-service engineering and architectural firm
in Wadsworth Ohio. Jim is experienced in overall project coordination/management, pressure
equipment, piping design, analysis, specifications,
support design, mechanical system requirements and documentation requirements. Areas of technical competence include ASME
piping and pressure vessel codes, stress analysis, and field troubleshooting piping system support, vibration and expansion problems.
Mr. Meyer is a member of ASME and has been involved in
the ASME B31.1 and ASME B31.3 Section committees for over
35 years. He is currently Chair of the ASME B31.3 Process Piping Section Committee, Chair of the ASME B31 Pressure Piping Standards Committee, Vice Chair of ASME B31 Mechanical
Design Committee, and serves on the ASME Board on Pressure
Technology Codes and Standards. In the past, Jim has served as
Chair of ASME B31.1 Power Piping Code Section Committee.
Past projects and work experience has involved major oil
refineries, petrochemical plants, fossil, nuclear, solar and alternative energy generation as well as cryogenic and vacuum test
facilities.
In addition to his engineering work, Jim is also an instructor for
ASME teaching courses on ASME B31.1 and B31.3 though out
the world.
MILLER, UREY R.
Mr. Miller is an ASME Fellow and has more than
30 years of experience in the pressure vessel industry. He has participated in ASME Pressure Vessel Code Committee activity for well more than
20 years. He is a Registered Professional Engineer
in Indiana and Texas. He is currently a member
of the following ASME Boiler and Pressure Vessel Committees: Boiler and Pressure Vessel Standards Committee
Subcommittee Pressure Vessels—Section VIII Subgroup Design—
Section VIII (Chairman) Special Working Group for Heat Transfer
Equipment (past Chairman) Special Committee on Interpretations—
Section VIII Subcommittee Design.
Mr. Miller has been the Chief Engineer with the Kellogg Brown
& Root Company (KBR), a major international engineering and
construction company for the petrochemical industry, since 1992.
In this position, he consults on a wide array of subjects including
pressure vessel, heat exchanger, and piping design issues, including application and interpretation of all ASME Code requirements.
He has had extensive experience with international projects. He
has provided significant engineering support and advice to KBR
projects throughout the world. In the role as Chief Engineer, he
has traveled extensively providing engineering support for projects
in Brazil, Malaysia, Egypt, Algeria, Nigeria, Philippine Islands,
South Africa, United Kingdom, Mexico, etc. in addition to a variety of projects in United States. He has experience in refinery,
petrochemical, liquefied natural gas, ammonia, phenol, and other
types of projects. Previously, he held responsible positions related
to process pressure equipment at Union Carbide Corporation and
Foster Wheeler Energy Corporation. In addition, he has had over
eight years experience in designing pressure vessels for nuclear
power generation applications with the Babcock and Wilcox Co.
Mr. Miller has a Bachelor’s Degree in Mechanical Engineering
(cum laud) from the University of Evansville (Indiana).
MOEN, RICHARD A.
Richard (Dick) Moen has been a member of numerous Boiler and Pressure Vessel Code committees
since 1969. Richard (Dick) Moen was an active
member of various Boiler and Pressure Vessel
Code committees from 1969, until his retirement in 2005. During that time span, he served
on the Standards Committee, the Subcommittee
on Materials, the Subcommittee on Nuclear Power, and additional
Subgroups and Task Groups serving in those areas. He is a life
member of ASM International.
Richard Moen earned a BS degree in Metallurgical Engineering
from South Dakota School of Mines and Technology in 1962, with
xxiv t Contributor Biographies
additional graduate studies through the University of Idaho and
the University of Washington. He has spent his entire professional
career in the field of nuclear energy, beginning in research and
development, and then with commercial power plant construction,
operation support, and maintenance. He now consults and teaches
through Meon Technical Services.
Richard Moen’s primary area of expertise is in materials behavior and applications. He has authored numerous papers and has
been involved in several national materials handbook programs.
And with his long-time involvement in the ASME Boiler and Pressure Vessel Code, he has authored a popular book entitled “Guidebook to ASME Section II, B31.1, and B31.3—Materials Index.”
His classes are built around that book.
MOKHTARIAN, KAMRAN
Kam Mokhtarian graduated from the North-western
University with a Master of Science degree, in 1964.
He worked for Chicago Bridge and Iron Company
from 1964 through 2000, in a variety of assignments. He was responsible for design and analysis
of nuclear vessels and pressure vessels for a number
of years. He also provided technical consulting to
the engineering staff.
Mr. Mokhtarian has been involved with the ASME B&PV Code
Committee, since 1980. He has served as member and chairman of
several committees. He was Chairman of Subgroup Design of Subcommittee VIII and the Vice-chairman of Subgroup Fabrication and
Inspection. He is presently the Vice-chairman of Subcommittee VIII.
Mr. Mokhtarian is also a member of the Post Construction Standards Committee and the Vice-chairman of the Subcommittee on
Flaw Evaluation. He has also served as an associate editor of the
ASME’s Journal of Pressure Vessel Technology for several years.
Mr. Mokhtarian has been an active member of the Pressure Vessel
Research Council (PVRC) since 1980 and has served as Chairman of
several committees. He is presently the Chairman of the PVRC. He
has authored several WRC Bulletins, including Bulletin 297 that has
become a major resource for pressure vessel designers. He has also
been teaching a number of pressure vessel related ASME courses.
MORTON, D. KEITH
Mr. D. Keith Morton retired from the Department
of Energy’s Idaho National Laboratory (INL)
after nearly 39 years of working in the Applied
Mechanics group. Mr. Morton gained a wide variety of structural engineering experience in many
specific disciplines, including piping stress analyses, performing plant walk downs, consulting
with the U.S. Nuclear Regulatory Commission on plant structural
evaluations, developing life extension strategies for the Advanced
Test Reactor, performing full-scale seismic and impact testing of
components, developing the DOE standardized spent nuclear fuel
canister, and establishing a test methodology that allows for the
quantification of true stress-strain curves that reflect strain rate
effects. His most recent work has been as a consultant, supporting
the Department of Energy’s advanced reactor efforts.
Mr. Morton is active in many ASME Boiler and Pressure Vessel
Code Committees for Section III. He is the Chair of the Working
Group on Design of Division 3 Containment Systems, the Chair of
the Subgroup on Containment Systems for Spent Nuclear Fuel and
High-Level Radioactive Material, a member of the Working Group
on High Temperature Gas-Cooled Reactors, a member of the Subgroup on High Temperature Reactors, a member of the Subgroup
on Component Design, a member of the BPV III Executive Committee, a member of the Special Working Group on Editing and
Review, a member of the BPV III Standards Committee, and an
Ex-Officio Member of the ASME Board on Nuclear Codes and
Standards. He has co-authored over twenty-five conference papers,
one journal article, co-authored an article on DOE spent nuclear
fuel canisters for Radwaste Solutions, and co-authored two chapters for multiple editions of the Companion Guide to the ASME
Boiler & Pressure Vessel Code.
Mr. Morton received a B.S. in Mechanical Engineering from
California Polytechnic State University in 1975 and a Masters of
Engineering in Mechanical Engineering from the University of
Idaho in 1979. He is a Registered Professional Engineer in the state
of Idaho for both mechanical engineering and structural engineering.
MUSTO, THOMAS M.
Tom Musto has a Bachelor of Science in Mechanical Engineering from Purdue University at West
Lafayette, IN. He is a Registered Professional
Engineer in the States of Illinois and Kansas. Mr.
Musto is a Senior Manager at Sargent & Lundy,
LLC in Chicago, Illinois, where he currently
serves as the Discipline Manager for the Mechanical Engineering Department of the company’s Nuclear Power
Technologies business group.
During his career at S&L, Mr. Musto has had the opportunity to
work on a wide variety of projects for nuclear power plants including the restarting of shutdown power stations, power uprates, major
component replacements, and system upgrades. He also served as
the S&L Program Manager and Mechanical Engineering Lead for
the Callaway Nuclear Plant Buried ESW Piping Replacement project, which was the first project in the United States to install high
density polyethylene (HDPE) piping in an ASME Class 3, nuclear
safety-related application.
Mr. Musto has been active in the development of ASME Codes
and Standards for non-metallic materials since 2008. He currently serves as Chair of the Nonmetallic Pressure Piping Systems
(NPPS) Subcommittee on Nonmetallic Materials and Chair of the
BPV III Working Group on HDPE Design of Components. He is
also a member of the NPPS Standards Committee, the BPV III
Subgroup on Component Design, the BPV III Working Group on
HDPE Materials, the BPV III Special Working Group on HDPE
Stakeholders and the BPV XI Working Group on Non-Metals
Repair/Replacement Activities.
NEWELL JR., WILLIAM F.
Bill Newell, Jr. is Co-Founder/Vice President
of Euroweld, Ltd., a supplier of specialty welding consumables and technology. He is also
the President and Founder of W. F. Newell &
Associates, a consulting firm that specializes in
welding engineering. Mr. Newell has been heavily involved in the power generation (nuclear,
fossil, hydro), industrial, manufacturing, heavy & highway
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t xxv
construction and auto racing industries for over 40 years, both
domestic and internationally. Particular expertise includes piping, structural, pressure vessels, valves, and associated components as they relate to welding, materials, and nondestructive
testing. Mr. Newell utilizes his diversified experience in implementing welding technologies toward procedure and process
evaluation, development and implementation of dry/wet welding
techniques, corrosion control, and reduction of residual stresses.
He also provides primary and third party review of procedures
and specifications, including domestic and international research
and development.
Clientele ranges from small operations to Fortune 500 corporations. Mr. Newell has been very successful assisting clients during
planned and unplanned shutdowns or turnarounds as well as new
projects. In addition to technical consulting, he actively provides
component/hardware failure evaluations and project management of major turn-key repair operations. Specialized approaches,
techniques and/or equipment are utilized depending upon clients’
needs.
An authority in his field, Mr. Newell also provides expert testimony in welding-related areas. For nearly four decades, he has
been giving technical presentations for AWS, EPRI, WRC and
other venues. In the last decade, much attention has been given
to committee participation with ASME and AWS welding codes
as well as making presentations in a variety of conferences and
seminars. He also prepares and implements training programs for
management, engineering, craft, supervision and Quality Assurance personnel.
Mr. Newell holds an International Institute of Welding (IIW)
International Welding Engineer (IWE) diploma and is a licensed
Professional Engineer in Ohio, North Carolina, South Carolina,
Tennessee, Texas and Alberta, Canada. He holds four patents and a
Bachelor of Science in Welding Engineering from The Ohio State
University.
NICKERSON, DOUGLAS B.
Douglas B. Nickerson graduated from CalTech
with a BSME. He was a registered Engineer in
the State of California and is a Fellow of ASME.
He worked in the Aerospace Industry until 1965
when he founded his consulting business, Stress
Analysis Associates. During his tenure in the
Aerospace Industry he developed the Hi-V/L ®
pump for aerocraft boosterpump application. He was active in
dynamic analyses of pumps and valves as a consultant to most of
the commercial pump manufacturers including those manufacturing nuclear pumps.
As a corollary to the dynamic analysis of pumps and valves
Mr. Nickerson developed a number of computer programs to carry
out these analyses. Some of these programs were successfully marketed. Not only active in Engineering he helped organize the Fluid
Machinery Section of the Local ASME Section. In recognition of
his activities he was made “Engineer of the Month” of Southern
California for August 1973.
Mr. Nickerson was on the SURF Board of CalTech and was formerly its Chairman.
Douglas Nickerson had served on a number of ASME Section III
Committees and was Chairman of QR Subcommittee of QME.
Mr. Douglas B. Nickerson passed away since the completion of
the first edition.
NORDSTROM, EDWIN A.
On the personal side, Ed is a native of Kansas
who was educated at the University of Kansas as
an undergraduate and the Massachusetts Institute
of Technology where he earned graduate degrees
in both Chemistry and Management – the latter
from the Sloan School. He served in administrative positions for 16 years on school boards and
40 years in the Episcopal Church.
Without an engineering degree, Ed rose to be Manager of Process Engineering for a chemical company and then to VP Engineering for A O Smith Water Products Division. In the latter post,
he became active in ASME where he has served on Section IV
for 25 years. This activity continued across job changes to Amtrol
[Manager, Hot Water Maker Sales]; Viessmann Manufacturing
[COO for US operations]; Gas Appliance Manufacturers Association; and Heat Transfer Products.
ORTMAN, ED
Mr. Ortman earned a BSME from Worcester Polytechnic Institute and is currently a Principal Engineer with GE Power. Ed has close to 30 years in
the power industry with GE Power and it’s predecessor companies (CE, ABB, and Alstom). In
this time, Ed has worked in engineering and also
in research and development. In both roles, Ed’s
focus has been on boiler pressure parts and piping and the application of associated international codes and standards such as ASME
B&PVC Section I, B31.1, NBIC, and EN 12952. Ed is active on
ASME Boiler & Pressure Vessel Committees and currently serves
as the Vice Chair of BPV I on Power Boilers, Chair of BPV I SubGroup General Requirements & Piping, and Chair of BPV I SubGroup Solar Boilers. Ed is a former member of BPV I SubGroup
HRSG (now disbanded) as well as a former member of the NBIC
Subcommittee on Repairs and Alterations.
OSAGE, DAVID A.
Mr. Osage, President and CEO of the Equity
Engineering Group in Shaker Heights, Ohio, is
internationally recognized as an industry expert
and leader in the development and use of FFS
technology. As the architect and principal investigator of API 579 Fitness-For-Service, he developed many of the assessment methodologies and
supporting technical information. As the chairperson for the API/
ASME Joint Committee on Fitness-For-Service, he was instrumental in completing the update to API 579 entitled API 579-1/
ASME FFS-1 Fitness-For-Service. Mr. Osage provides instruction
on Fitness-For-Service technology to the international community
under the API University and ASME Master Class Programs.
Mr. Osage is also a recognized expert in the design of new equipment. As the lead investigator of the new ASME, Section VIII, Division 2, Boiler and Pressure Vessel Code (VIII-2), he developed a new
organization and writing style for this code and was responsible for
introducing the latest developments in materials, design, fabrication
and inspection technologies. These technologies include a new brittle fracture evaluation method, new design-by-analysis procedures
xxvi t Contributor Biographies
including the introduction of elastic-plastic analysis methods, and a
new fatigue method for welded joints. Mr. Osage is currently teaching
ASME Master Classes in design-by-analysis and fatigue that covers
the background of existing rules in VIII-2 as well as next generation
methods of analysis.
Mr. Osage was a lead investigator in revamping the API RiskBased Inspection (RBI) technology and software. The main focus of
this effort was a clean sheet re-write of API 581 Risk-Based Inspection
and the development of a new version of the API RBI software. He
is currently working on the next generation of RBI technology where
Fitness-For-Service assessment procedures will be used to compute
the Probability of Failure for Risk-Based Inspection.
Mr. Osage is the Chairman of the Board of the Welding Research
Council. The Welding Research Council (WRC) now incorporates
both the Materials Properties Council (MPC) and the Pressure Vessel Research Council (PVRC). These councils were created by the
Engineering Foundation, a coordinating organization of the major
engineering societies that was formed over one hundred years ago,
to meet the industry’s needs for knowledge regarding the properties and performance of materials in engineering applications. Mr.
Osage will be working to ensure that the vast amount of technology
and data of these organizations is preserved and made available to
industry.
Mr. Osage is an ASME Fellow, a licensed professional Engineer in
the states of Ohio and Michigan and an EY Entrepreneur of the Year,
2014 Regional Award Winner.
As an Adjunct Visiting Assistant Professor at Stevens Institute of
Technology, Mr. Osage has taught graduate level courses in strength
of materials and elasticity, structural analysis and finite element methods, and structural optimization.
Committee, Board on Pressure Vessel Technology and Council
on Codes and Standards. His principal accomplishment is his
role for the publication of common rules in ASME Code, European Code and French Code for the design of tube-sheets and
expansion bellows. Osweiller is the recipient of several awards
and certificates from ASME and PVP and was elevated to the
grade of Fellow by ASME in 2001 and is listed in the Who’s
Who in the World.
PARK, GARY
Gary Park is a Senior Program Engineer with
Iddeal Solutions LLC. Mr. Park has worked
in the Nuclear Industry since 1977. He has
achieved Level III in many Nondestructive
Examination Methods and managed Nuclear
Inservice Inspection Program both government and utility. Mr. Park is currently the Chair of the Boiler
and Pressure Vessel Standards Committee on Nuclear Inservice
Inspection. He sits on the Board on Nuclear Codes and Standards
as an Ex-Officio Member. He has been a member of the ASME
Committees since 1996. Mr. Park has authored PVP Papers concerning the change with ASME Boiler and Pressure Vessel Section XI Code. He has participated in the ASME Nuclear Training
Seminars providing presentation on ASME Code Pre-Service
and Inservice Inspection and Testing along with Lessons from
Past Construction Problems. Mr. Park is currently working with
a number of utilities in updating their ASME Section XI Inspection Programs.
OSWEILLER, FRANCIS
PASTOR, THOMAS P.
Francis Osweiller got international recognition
for his expertise in French, European and ASME
Pressure Vessel Codes & Standards. He has been
the head of the French delegation to CEN/TC 54
(European Technical Committee for Unfired Pressure Vessels) for several years and has chaired several committees such as Simple Pressure Vessels,
Testing & Inspection, Tubesheets and Bellows. Mr. Osweiller has
been actively involved in Europe with the development of the Pressure Equipment Directive and the new CEN Standard for Unfired
Pressure Vessels. He gave several courses on these issues in France
UK and USA. As member of the Main Committee of CODAP, he
developed several design rules for the French Pressure Vessel Code
(CODAP). His main contribution was the development of Tubesheet
Heat-exchanger rules to replace the existing (TEMA) rules.
Francis Osweiller obtained a Mechanical Engineering degree in
Paris, France. He started his career at CETIM-France with FEM
analysis applied to pressure vessels. He has published more than
40 papers in France, UK, Germany and US on European Codes,
ASME Code and Pressure Equipment Directive and gave lectures
at AFIAP, ICPVT (International Conference of Pressure Vessel
Technology) and ASME-PVP (Pressure Vessel & Piping Conference). He has been the representative for France at ICPVT and
ISO/TC11.
Since 1985 Osweiller has been actively involved in ASME
Boiler and Pressure Vessel Code organization where he is member of SCII/International Material Specifications, SCSVIII/
SWG on Heat Transfer Equipment, Post Construction Main
Mr. Pastor has over forty years’ experience working in the areas of stress analysis and pressure
vessel design. He holds a Bachelors and Masters
degree in Civil Engineering from the University
of Connecticut, with emphasis on structural design
and analysis.
Mr. Pastor began his career with Combustion
Engineering in 1977, where he was a member of the structural
analysis group, responsible for performing load analyses of nuclear
reactor internals subject to significant expertise in performing
finite element analyses and scientific programming.
In 1986 Mr. Pastor joined the Hartford Steam Boiler Inspection
and Insurance Co. (HSB) working in the Codes and Standards Group
in Hartford, Ct. During his 31 year tenure at HSB, Mr. Pastor rose
from staff engineer, to Manager Codes & Standards, Director, and
presently Vice-President Code & Standards. He has managed the
Codes & Standards (C&S) Group for over 25 years, and led the
development of several knowledge based databases which are used
today to provide Code technical support to over 3000 ASME Certificate Holders and Inspectors worldwide. Mr. Pastor’s ASME code
expertise is in pressure vessels, and he has taught basic to advanced
seminars on Section VIII, Division 1 over 150 times to audiences
around the world. He has authored numerous technical papers on the
subject of stress analysis and ASME Code developments, Mr. Pastor
is a licensed Professional Engineer in the states of Connecticut
and Indiana. He is currently serves on several ASME Committees
including the Board on Pressure Technology Codes & Standards
(Chairman), BPV Technical Oversight Management Committee
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t xxvii
(Chairman), Standards Committee on Pressure Vessels – BPV VIII,
and the Subgroups Design and General Requirements – BPV VIII.
PILLOW, JAMES T.
Mr. James (Jim) Pillow has over 35 years experience as a quality assurance and quality control
specialist in installation, repair and maintenance
of ASME power boilers, pressure vessels and
ancillary equipment in utility and industrial power
plants. Before joining Common Arc in 2007 as
Chair of the Operating Committee, Jim worked
for over 30 years with APComPower, a wholly
owned subsidiary of Alstom Power Inc., in Windsor, Connecticut.
While there he managed the company’s quality, welding, NDE and
construction engineering groups.
Jim has been a member of the American Society of Mechanical Engineers for nearly 25 years, during which he has been
actively involved in numerous committees, subgroups and task
groups, including: BPV I, Standards Committee – Power Boilers
(Member 1997–present); BPV I – Subgroup General Requirements
(Member 1988–present); BPV I – Subgroup Fabrication & Examination (Member 1988–present, Secretary 2001–2004, Chair 2004–
present); and the Board on Conformity Assessment (Member 2003–
2011). Jim has also been an active participant on the Committee on
National Board Inspection Code (NBIC–2000 to present), the NBIC
Subcommittee-Repairs and Alterations (2002–present), and is currently Chair, NBIC Repairs and Alterations Subgroup – Specific.
Jim is a recipient of the ASME Dedicated Service Award and
is co-author with Mr. John R. MacKay of the second edition of
“Power Boilers: A Guide to Section I of the ASME Boiler and
Pressure Vessel Code.”
RANA, MAHENDRA D.
Mahendra, an ASME Fellow has a bachelor’s
degree in mechanical engineering from M.S. University in Baroda, India, and a master’s degree in
mechanical engineering from the Illinois Institute
of Technology, Chicago, Illinois. He is a registered professional engineer in New York State.
He is an Engineering Fellow working in the
Engineering Department of Praxair, Inc. for the last 38 years. He is
involved in the areas of fracture mechanics, pressure vessel design,
pressure vessel development, and materials testing. He is also
involved in the structural integrity assessment, and fracture control
programs of pressure vessels. He is the Chairman of ASME Section XII Transport Tanks Standards Committee. He is a member of
several other ASME Boiler and Pressure Vessel Code committees:
member of Section VIII Standards Committee, member of joint
API/ASME Fitness for Service Committee, member of the Technical Oversight Management Committee of the Boiler and Pressure
Vessel Code and the member of Board on Pressure Technology,
Codes and Standards. Mahendra is also a member of several ISO,
ASTM and CGA (Compress Gas Association) standards committees. He has received several awards from the Pressure Vessel and
Piping Division for his contribution in organizing Codes and Standards sessions in Pressure Vessel and Piping Conferences. He is also
the recipient of ASME J. Hall Taylor Medal. He has given several
lectures in the pressure vessel technology topics in the USA and
abroad. He has taught a course on ASME Section VIII, Division 1
to ASME section of Buffalo New York. He is the co-recipient of
two patents and the co-author of over 30 technical papers. He also
has written several technical reports for his company.
RANGANATH, SAM
RAHOI, DENNIS
D. W. (Dennis) Rahoi is an authority on materials used in the pharmaceutical/biotechnology,
chemical process, fossil fuel, and nuclear power
industries. The author of more than 50 papers on
materials, corrosion and oxidation, he received
the Prime Movers Award in Thermal Electric
Generating Equipment and Practice by Edison
Electric Institute for work published on solving problems in high
pressure feedwater heaters. He currently consults in material selections, failure analysis and does other forensic metallurgical work.
Mr. Rahoi is also the current editor of Alloy Digest (an ASM International, Inc. publication) and is an active consultant to the Nickel
Institute. Mr. Rahoi was the first chairman of NACE’s Power
Committee and is active on many stainless steel ASTM and ASME
(including B31) materials committees. He is the current chairman of the ASME Sub-Group Non-Ferrous Materials for Section
II and holds a master’s degree in metallurgical engineering from
Michigan Technological University.
Mr. Rahoi’s work on writing many new ASTM specifications,
his active sponsoring of 10 pipe and tube specifications and his
active involvement in Welding Research Council and EPRI
research proposals on welding and repair keep him in constant
touch with the needs of industry. This, combined with his other
experiences and consulting, allow him to contribute to the current
chapter in this book with authority.
Dr. Sam Ranganath is the Founder and Principal at
XGEN engineering, San Jose, CA. XGEN, founded
in 2003, provides consulting services in fracture
mechanics, materials, ASME Code applications
and structural analysis to the power plant industry.
Before that he held various leadership positions
at General Electric for 28 years. Dr. Ranganath is
a Fellow of the ASME and has been active in the development of
Section III and Section XI, ASME Code rules for the evaluation and
inspection of nuclear pressure vessel components. Sam has a Ph.D.
in Engineering from Brown University, Providence, RI and an MBA
from Santa Clara University, Santa Clara, CA. He has also taught
Graduate Courses in Mechanical Engineering at Santa Clara University and Cal State University, San Jose for over 15 years.
RAO, K. R.
KR Rao retired as a Senior Staff Engineer with
Entergy Operations Inc. and was previously with
Westinghouse Electric Corporation at Pittsburgh,
PA and Pullman Swindell Inc., Pittsburgh, PA.
KR got his Bachelors in Engineering from Banaras
University, India with a Masters Diploma in Planning from School of Planning & Architecture,
New Delhi, India. He completed Post Graduate
Engineering courses in Seismic Engineering, Finite Element and
xxviii t Contributor Biographies
Stress Analysis, and other engineering subjects at Carnegie Mellon
University, Pittsburgh, PA. He earned his Ph.D., from University of
Pittsburgh, PA. He is a Registered Professional Engineer in Pennsylvania and Texas. He is past Member of Operations Research Society
of America (ORSA).
KR was Vice President, Southeastern Region, ASME International. He is a Fellow of ASME, active in National, Regional,
Section and Technical Divisions of ASME. He has been the Chair,
Director and Founder of ASME EXPO(s) at Mississippi Section. He was a member of General Awards Committee of ASME
International. He was Chair of Codes & Standards Technical
Committee, ASME PV&PD. He developed an ASME Tutorial for
PVP Division covering select aspects of Code. KR is a Member,
Special Working Group on Editing and Review (ASME B&PV
Code Section XI) for September 2007 – June 2012 term.
Dr. Rao is a recipient of several Cash, Recognition and Service
Awards from Entergy Operations, Inc., and Westinghouse Electric
Corporation. He is also the recipient of several awards, Certificates
and Plaques from ASME PV&P Division including Outstanding
Service Award (2001) and Certificate for “Vision and Leadership”
in Mississippi and Dick Duncan Award, Southeastern Region,
ASME. Dr. Rao is the recipient of the prestigious ASME Society
Level Dedicated Service Award.
Dr. Rao edited “Energy and Power Generation Handbook:
Established and Emerging Technologies” published by ASME
Press in 2011. Dr. Rao edited the “Continuing and Changing
Priorities of ASME B&PV Codes and Standards” published in
2014 and “Global Applications of ASME Boiler & Pressure Vessel Code” published in 2016. Dr. Rao continues to be the editor
of “Companion Guide to The ASME Boiler & Pressure Vessel
Code” since the first edition published in 2000. Dr. Rao founded
the annual “Early Career Technical Conference (ECTC)” and
Chair since then till 2014. Since then Dr. Rao is an “Advisor” for
this conference which is holding its 17th Annual ECTC at UAB,
Birmingham, AL.
Dr. Rao is a Fellow of American Society of Mechanical Engineers, Fellow of Institution of Engineers, India and a Chartered
Engineer, India. Dr. Rao was recognized as a ‘Life Time Member’
for inclusion in the Cambridge “Who’s Who” registry of executives and professionals. Dr. Rao was listed in the Marquis 25th
Silver Anniversary Edition of “Who’s Who in the World” as ‘one
of the leading achievers from around the globe’.
REEDY, ROGER F.
Roger F. Reedy has a B.S. Civil Engineering from
Illinois Institute of Technology (1953). His professional career includes the US Navy Civil Engineering Corps, Chicago Bridge and Iron Company
(1956–1976). Then he established himself as
a consultant and is an acknowledged expert in
design of pressure vessels and nuclear components
meeting the requirements of the ASME B&PV Code. His experience
includes design, stress analysis, fabrication, and erection of pressure
vessels and piping components for nuclear reactors and containment
vessels. He has expertise in the design, construction of pressure vessels and piping components for fossil fuel power plants, chemical
plants and refineries. Mr. Reedy has been involved in licensing,
engineering reviews, welding evaluations, quality programs, project
coordination and ASME Code training of personnel. He testified as
an expert witness in numerous litigations involving pressure vessels,
piping, and quick-actuating closures and before different regulatory
groups. His litigation and arbitration experience has included a number of international lawsuits. Because he is a structural engineer, he
has testified regarding both steel and concrete structures.
Mr. Reedy has written an important article regarding unsafe
pressure vessels on cement trucks that was published by the
National Board of Boiler and Pressure Vessel Inspectors in 2011,
and another NBBPVI article on quick actuating closures for 2012.
He also writes a summary of all changes made to the ASME
B&PV Code in each Addenda published since 1950 to the present, that is maintained in a computer database, RA-search. Mr.
Reedy has served on ASME BP&V Code Committees for more
than 45 years being Chair of several of them, including Section
III for 15 years. He is still active on Section III and Section VIII.
Mr. Reedy was one of the founding members of the ASME Pressure Vessel & Piping Division. Mr. Reedy is registered Engineer
in seven states. He is a recipient of the ASME Bernard F. Langer
Award and the ASME Centennial Medal and is a Life Fellow
Member of ASME.
Mr. Reedy has consulted with clients in Europe, Asia, Africa,
and South America. He has helped develop a Nuclear Code Case
for a European client that permits the use of a unique system of
piping supports that can significantly reduce the time of construction because welding is not involved.
RODERY, CLAY D.
Clay D. Rodery is the BP Downstream S&OR
(Safety & Operational Risk) Segment Engineering Technical Authority for Pressure Vessels and
Piping. He has over 36 years of experience providing technical expertise in the areas of pressure
vessels and piping to Amoco and BP Refining, Petrochemicals, and Upstream facilities and projects
worldwide. After earning his B.S. in Civil Engineering from Purdue
University in 1981, he joined the Amoco Oil Company Texas City
Refinery, where he worked in project, maintenance, and inspection
engineering roles. In 1990, he transferred to the Amoco Oil Refining & Transportation Engineering Department in Chicago as the
pressure vessel specialist in the Materials and Standards Group. In
1995, he became the principal vessel specialist within the Amoco
Corporation Worldwide Engineering & Construction Department in
Houston in the Mechanical Equipment Team. Upon the BP-Amoco
merger in 1999, he transfered to the BP Chemicals Technology &
Engineering Department Specialists Skills Team as pressure vessel
and piping specialist, and in 2004 was appointed Pressure Vessel and
Piping Advisor for the Petrochemicals Segment. In 2006, he assumed
a role as the Fixed Equipment Technical Authority for the BP Whiting (Indiana) Refinery Modernization Project, where he served until
moving to his current role in 2011.
Clay became active with the ASME Boiler and Pressure Vessel
Code in 1993. He joined the Subgroup on Fabrication & Examination (BPV VIII) in 1997, and the Subgroup on Design in 1999. In
May 2000, he was appointed Chairman of the Subgroup on Fabrication & Examination (a position he held until June 2015), and
member of the Committee on Pressure Vessels. Clay is Vice Chair
of the Post Construction Standards Committee, the Subcommittee
on Repair and Testing, and Subgroup on Mechanical Repairs. He
is currently Chairman of the Post Construction Subcommittee
on Flange Joint Assembly that is responsible for ASME PCC-1,
Guidelines for Pressure Boundary Bolted Flange Joint Assembly.
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t xxix
As a member of the Design & Analysis Technical Committee
of the ASME Pressure Vessels and Piping Division, Clay has been
active as an Author, Reviewer, Session Developer/Chair/Co-Chair,
Editor, Technical Program Representative, and Tutorial Presenter,
and has received several awards from the Pressure Vessels and
Piping Division for his contributions. Clay was elected an ASME
Fellow in 2011, and was the recipient of the 2015 ASME Dedicated Service Award.
Clay is a member of the API Subcommittee on Inspection and
Mechanical Integrity and the Task Group on Inspection Codes. He
is former Team Leader of the Process Industry Practices (PIP) Vessel Function Team.
ROSENFELD, MICHAEL J.
Michael J. Rosenfeld, PE is Vice President and
General Manager of Kiefner/Applus-RTD (dba
Kiefner & Associates) in Worthington, Ohio.
He holds a BS in mechanical engineering from
the University of Michigan (1979) and a MS in
mechanical engineering from Carnegie-Mellon
University (1981). He began his career at Westinghouse Electric where he worked on finite element analyses of
power plant generator stator structures. He then worked at EDS
Nuclear (later Impel Corporation) performing stress analyses of
piping systems, equipment, and site structures for nuclear power
stations. He then joined Battelle Memorial Institute-Columbus Laboratories where he performed design and analysis work on industrial and defense equipment, and became involved with research in
areas concerning natural gas pipeline integrity.
The focus of Mr. Rosenfeld’s career has been on oil and gas pipeline integrity since joining Kiefner & Associates, Inc. (KAI) as Senior Structural Engineer in 1991. He then served as President from
2001 to 2011. While at KAI, he has performed numerous pipeline
failure investigations, stress analyses of buried pipelines subjected
to geotechnical and live loadings, fitness for service evaluations for
pipelines affected by various types of degraded conditions, technical procedure development for integrity management planning, and
has carried out industry-funded research on pipeline damage mechanisms. Mr. Rosenfeld is a current member of the ASME B31.8 Gas
Transmission & Distribution Piping Section Committee, the ASME
B31 Mechanical Design Technical Committee, the ASME B31
Standards Committee, and the ASME Board of Pressure Technology Codes & Standards. He is also ASME Professional Development’s designated instructor for the B31.8 Code seminar, and was
the primary author of the recent major revision to ASME B31G.
He is a past member of the API RP-1117 Task Group on Pipeline
In-Service Relocation, and the ASCE-ASME Joint Task Group
that developed the American Lifelines Alliance “Guidelines for the
Design of Buried Steel Pipe.” He has authored or co-authored over
40 technical papers on various pipeline-related subjects.
ROWLEY, C. WESLEY
C. Wesley Rowley is Vice President, Engineering
& Technical Services, with The Wesley Corporation in Tucson, AZ. He has been with TWC since
1985. Mr. Rowley manages engineering and nonmetallic structural repair activities for infrastructure projects. He has published numerous reports
and technical papers for EPRI, ASME, ICONE Conferences, NRC
– ASME Pump & Valve Symposiums, and other industry events.
He is a recognized industry technical expert on use of non-metallic
materials and the application of non-metallic structural repairs, as
well as risk-informed inservice testing of pumps/valves/snubbers and
large containment leakage rate testing.
Mr. Rowley has performed consulting projects and repair projects for numerous power plants, refineries, pipelines, hydro facilities, and petroleum storage facilities.
He is a member of the ASME Post Construction Committee,
the Sub-committee on Repair & Testing, and the Chairman of the
Sub-group on Non-metallic Repair. He is also a member of the
ASME Committee on Nonmetallic Pressure Piping Systems, the
Sub-committee on Nonmetallic Materials, the Sub-committee on
FRP Pressure Piping Systems, and the Sub-group on FRP Materials. He is an honorary member of the ASME Operations and Maintenance Committee and a delegate member of the ASME Board
on Nuclear Codes and Standards (also past ASME Vice President/
Chairman of the Board and member for over twenty years).
Mr. Rowley is a retired Submarine Captain in the U. S. Naval
Reserve. He has a M.A. degree in International Relations and Strategic Studies from the Naval War College (1986). He also has a
B.S. in General Engineering (1965) and M.S. in Nuclear Engineering from the University of Illinois (1967). Mr. Rowley is a Registered Professional Engineer.
SAMMATARO, ROBERT F.
The late Mr. Sammataro was Proto-Power’s Program Manager — ISI/IST Projects. He was responsible for Proto-Power’s Inservice Inspection (ISI)
and Inservice Testing (IST) programs. These programs included development and implementation
of programs involving ISI, IST, design integrity,
design reconciliation, 10CFR50, Appendix J, integrated leakage rate testing, and in-plant and out-plant training and
consulting services.
Mr. Sammataro was also responsible for Proto-Power’s ISI and
IST Training Programs has developed Proto-Power’s three-day
Workshop on Containment Inservice Inspection, Repair, Testing,
and Aging Management. He was recognized as an expert in containment inservice inspection and testing.
Mr. Sammataro was the past Chair of the ASME PV&P Division (1999–2000), General Chair of PVP Conference (1999) and
was the Technical Program Chair (1998).
He was a member and chair of an ASME Section XI Subgroup
and a member of an ASME Section XI Subgroup Subcommittee.
He was a past member of the ASME BP&V Code Main Committee
(1989–1994). Mr. Sammataro was an ASME Fellow. Mr. Sammataro earned BSCE and MSCE from Rensselaer Polytechnic Institute.
SCARTH, DOUGLAS
Douglas Scarth received a B.Sc. and M.Sc. in
Mechanical Engineering from the University
of Manitoba, and a Ph.D. in Materials Science
from the University of Manchester. Dr. Scarth
is currently a Technical Director – Fracture
Programs with Kinectrics, Inc., in Toronto,
Canada. He was previously with the Research
xxx t Contributor Biographies
Division of Ontario Hydro. His work experience includes structural integrity evaluations of nuclear and fossil plant components
containing flaws. Dr. Scarth has been involved in development of
methodologies for evaluating the structural integrity of nuclear
pressure boundary components, including CANDU reactor
Zr-Nb pressure tubes in the areas of delayed hydride cracking,
fatigue and fracture toughness. He has participated in development of engineering codes and standards for fitness for service
assessments of pressure boundary components including Section
XI of the ASME Boiler and Pressure Vessel Code. Dr. Scarth is
a member of the Section XI Standards Committee on Nuclear
Inservice Inspection, and the Section XI Subgroup on Evaluation Standards. He is Chair of the Section XI Working Group on
Pipe Flaw Evaluation, and a member of the Section XI Working Group on Flaw Evaluation. Dr. Scarth is also a member of a
number of Task Groups under Section XI that are associated with
structural integrity evaluations.
SCOTT, BARRY
Barry Scott is currently Director of Quality
Assurance Department (Power) with responsibility to provide QA/QC support for the engineering, procurement and construction phases
of Power projects. Barry has experience in the
development, implementation and auditing of
Quality Programs. He has considerable knowledge of industry Quality Standards, including ISO 9000, 10CFR50
Appendix B, NQA 1 and Government (DOE, DOD) requirements.
Barry has extensive experience with projects and project engineering management with special expertise in the structural design of
Nuclear Power Plant structures including design of reinforced concrete Containment structures. Barry has been a Member of various ASME Section III committees including Subgroup on General
Requirements, Subcommittee on Nuclear Power and Joint ASMEACI Committee on Concrete Components for Nuclear Service for
more than 30 years.
Barry has a Master of Science in Civil Engineering from Drexel
University and is a licensed PE (Civil Engineering) in the states of
Pennsylvania, California and Washington. He is a certified Lead
Auditor in accordance with the requirements of ASME NQA-1 and
previously held certification as an ACI Level III Concrete Inspector as required by the ASME Section III Division 2 Code.
SHELLEY, BERNARD F.
Bernard F. Shelley has a B.S. in Mechanical
Engineering from West Virginia Institute of
Technology and a Masters of Mechanical and
Aerospace Engineering from the University of
Delaware. He has 44 years experience in applying engineering principles, computers, and Codes
and Standards to solving design of processing equipment and vessels in the chemical industry. Mr. Shelley spent the first three
years of his career working for DuPont designing textile processing equipment before joining the Franklin Institute Research Labs
and designing equipment for the bakery industry. He then spent
about 2 years at Hercules beginning his career in chemical equipment design and then moved to ICI Americas in 1975 where he
worked for almost 18 years designing all types of chemical processing equipment. He then left ICI to join BE&K and continued
designing chemical processing equipment primarily for DuPont
before rejoining DuPont in 1995 to the 2012 when he retired. At
DuPont Mr. Shelley designed vessels, tanks and heat exchangers
both metallic and non-metallic. After retirement, Mr. Shelley has
worked part-time as a consultant to both DuPont and Chemours
till the present continuing the design of metallic and non-metallic
process equipment. Mr. Shelley participated in the writing of the
MTI/SPI Quality assurance report published in 1978 and has participated in the ASME RTP-1 committee since its first meeting
in 1980 having served as Design and Fabrication Subcommittee
Chairman for almost 15 years and contributing heavily to several
sections of the RTP-1 standard. He also serves on the RTP-1 Certification Subcommittee. In 1995 he became a member of ASME
Section X and is responsible for the recent addition of Class III
vessels into this Code. He was elected vice-chair of Section X in
2014 and is continuing as vice chair for a second term. He also
serves on the ASME Boiler Code Technical Oversight Management Committee, the Hydrogen Project Team, the Section VIII
Subgroup on Fabrication and Examination, the Boiler and Pressure
Vessel Administrative Committee, the working group for the reorganization of Section V and the Structures for Bulk Solids committees. In addition, he is chairman of the NBIC FRP Subgroup where
he helped developed inspection and repair procedures in the NBIC
for FRP tanks and vessels. He was also the leader of the PIP Vessel Function teams where he developed the current FRP practice
based on RTP-1 and Section X. With his various Code committee
memberships Mr. Shelley has assisted in many projects to further
the usefulness and safety of the design of vessels and tanks.
Mr. Shelley is a registered professional engineer in the State of
West Virginia.
SIMS, ROBERT J.
Mr. Sims has over 50 years experience in design,
analysis, troubleshooting, design audit, mechanical integrity evaluation, leading risk based reviews
and failure analysis. He is a recognized authority
in risk-based technologies for optimizing inspection and maintenance decisions, high pressure
equipment and mechanical integrity evaluation of
existing equipment.
Bob was President of ASME for 2014–2015 and is a past member of the ASME Board of Governors, a past Chairman and Vice
Chairman of the ASME Post Construction Committee. Bob is a
past Vice Chairman of the ASME/API Joint Fitness-For-Service
Committee. He is also a past ASME Senior Vice President of Codes
and Standards, past ASME Vice President of Pressure Technology
Codes and Standards, a current member and past Chairman of the
ASME Subgroup on High Pressure Vessels, Section VIII, Div. 3,
and past Chairman of the ASME Task Group on Risk Analysis
for the Critical Assets Protection Initiative plus other committee
involvement such as the ASME B31.3 Subgroup on High Pressure
Piping.
Bob is currently employed by Becht Engineering Co., Inc. and
was previously employed by Exxon Research and Engineering Company as a Pressure Equipment Specialist. He has a BS in Mechanical Engineering from Vanderbilt University and is an ASME Fellow
with more than 20 publications and three patents.
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t xxxi
SMITH, CLAYTON T.
Principle Member, Smith Associates Consulting
Group, LLC, expertise in nuclear and non-nuclear
industry Codes and Standards.
Mr. Smith’s over 30 years of experience includes
extensive 10 CFR Part 50, Appendix B, ACI,
ASME Section III, ASME Section XI, and NQA-1
Quality Assurance program creation. He specializes in Nuclear Safety Related, ASME Section III,
Division 1 & 2 design, construction, and procurement; Section XI
nuclear power plant repair and replacements, coupled with traditional non-nuclear ACI, ASME and AWS Code design, construction, fabrication & installation; and National Board Inspection Code
(NBIC) alteration and repair activities.
Mr. Smith’s background also includes 12 years of Safety Conscious Work Environment program assessment, development,
implementation, & maintenance. He is a member of the National
Association of Employee Concerns Professionals (NAECP) and a
trained employee concerns investigator. In 2009 he worked with
others in the creation of the Nuclear Energy Institute (NEI) “Guidelines for Establishing a Safety Conscious Work Environment for
New Nuclear Power Plant Construction Sites” (NEI 09-12) document, which was published in February 2010. Most recently, he
has been a representative for a large EPC for the on-going efforts in
the commercial nuclear industry to implement NEI 09-07 “Fostering a Strong Nuclear Safety Culture.”
Mr. Smith is a multidiscipline NDE and QC Level III, and
holds various ACI certifications. He is the Vice Chair of the
ASME Board of Nuclear Codes and Standards (BNCS); a member of Board of Conformity Assessment (BCA), ASME Section
III Standards Committee (BPV III) and Committee for Nuclear
Certification (CNC); and as chair/vice-chair, as well as being an
active member, in many other ACI, ASME, and AWS Standards
Development Organization Committees. Finally, Mr. Smith is a
member of the NEI industry support groups for SCWE and QA,
as well as ICONE Technical Program Chair of the ASME Nuclear
Engineering Division (NED) Executive Committee (EC), Chair of
the NED EC Technical Committees, and participates on the IAEA
sector for International Codes and Standards.
SOWDER JR., WILLIAM K.
William K. (Ken) Sowder, PhD is a Senior
Consultant to the nuclear industry with Quality Management Services LLC. He works
with manufactures and suppliers to help them
develop their management systems and quality
management programs to meet the requirements
of codes and standards such as ASME Section
III, NQA-1, ISO 9001 and IAEA GS-R-3. He is a certified Lead
Auditor to ASME Section III and ASME NQA-1 requirements;
and is also an instructor for ASME and teaching 4 of their Public Courses. These courses were developed to help the nuclear
users understand and effectively use the ASME nuclear codes
and standards to meet today’s nuclear challenges. He worked
with various engineering and construction companies during the
1970–1980 in engineering and quality assurance and also held
a Nat’l Board Commission as an Authorized Nuclear Inspector
(ANI). During the 1990–2008 time frame he worked 17 years
at the Department of Energy’s Idaho National Energy Laboratory (INEL) and then was assigned to the ITER (International
Thermonuclear Experimental Reactor) fusion project on-site in
Germany and France from 2004–2008 as the Responsible Officer
and Division Head Quality Assurance for the ITER Project. From
2008–2009 he was employed as an Expert Consultant reporting
to the ITER’s Director General and his Deputy Director General
for Safety and Security. He helped develop and write the management systems for ITER to manage their interfaces with international organizations such as IAEA, ASME, JSME and ISO and
to demonstrate how the ITER Project would satisfy the requirements of the various nuclear management standards and those of
the French Nuclear Regulator. He is a member of various ASME
Section III Committees, NQA-1 Committees, and is an ASME
BNCS member. He was also a member of the US TAG to TC 176
(ISO 9001) for ten years until 2016.
SOWINSKI, JAMES C.
Mr. Sowinski is a Consulting Engineer for The
Equity Engineering Group, Inc. in Shaker Heights,
Ohio. He has experience in the refining and petrochemical industries as an owner-user and as a
consultant providing engineering support. He provides plant engineering support to maintenance
and inspection personnel and performs design/analysis/re-rate calculations of pressure containing equipment to evaluate mechanical
integrity and improve reliability. Mr. Sowinski is responsible for
Equity’s “R” Certificate of Authorization issued by The National
Board of Boiler and Pressure Vessel Inspectors.
Mr. Sowinski was involved in the development of the new ASME,
Section VIII, Division 2, Boiler and Pressure Vessel Code and was
a contributing author of the ASME Section VIII, Division 2, Criteria
and Commentary. He is Vice-Chair of the ASME Boiler and Pressure
Vessel VIII Subgroup on Design and also serves on the Subgroup on
General Requirements.
Mr. Sowinski is a Registered Professional Engineer in the States
of Ohio and Texas.
STAFFIERA, JIM E.
Jim E. Staffiera earned a BS in Mechanical
Engineering from Drexel University in 1971
and a Masters in Business from Old Dominion
University in 1975. He has been involved with
nuclear power plant containment vessel and steel
structure design, fabrication, construction, and
operation since 1971. Originally employed by
Newport News Shipbuilding and then Newport
News Industrial Corporation (a subsidiary company specializing
in commercial nuclear activities), he assisted with the development of commercial nuclear fabrication programs for ASME
Code N-type Certificate authorization. This progressed into
nuclear component fabrication and construction activities, eventually resulting in his employment with FirstEnergy Corporation
at the Perry Nuclear Power Plant in Perry, Ohio, where he worked
in the Contract Administration, QA/QC, Structural Mechanics,
and Project Engineering Units and was frequently involved with
Code-related issues.
xxxii t Contributor Biographies
Jim has been a member of ASME since 1972 and has been
involved in numerous ASME Boiler and Pressure Vessel Code
Committee activities since 1981, holding positions as Chair, Secretary, and Member of various Section XI committees on requirements for commercial nuclear power plants. He chaired the
Subgroup and Working Group on Containment and was a member
of the Subgroup on Water-Cooled Systems. He is a past member of the Subcommittee on Nuclear Inservice Inspection and is
currently a long-term member of the Special Working Group on
Editing and Review.
Jim is an active member of the ASME Pressure Vessels and Piping (PVP) Division, having been Chair of the Codes and Standards
(C&S) Technical Committee, C&S Technical Program Representative for the annual ASME Pressure Vessels and Piping Conference, and Publicity Chair for the Division.
He has been a member of the American Society for Quality
(ASQ) since 1975, with two three-year periods of certification as a
Certified Quality Engineer (CQE).
Jim has been involved in several nuclear industry initiatives, most
recently as a member of the Expert Panel for the EPRI Containment
Integrated Leak-Rate Test (ILRT) Interval Extension Project.
He is now retired from full-time employment and doing consulting work for nuclear facilities, specializing in security-related
initiatives and compliance with regulatory requirements for threat
mitigation.
STANISZEWSKI, STANLEY (STAN)
Stanley Staniszewski is a senior Mechanical
Engineer with the U.S. Department of Transportation, Pipelines and Hazardous Materials
Safety Administration. He is a ‘76 Alumni of
the Fenn College of Engineering, from Cleveland State University of Ohio and has completed
graduate level course work in Business Administration at Johns Hopkins University and advanced engineering
degree work at the University of Virginia. Mr. Staniszewski has
been a member of the American Society of Mechanical Engineers, since joining as a student. He currently serves on the ASME
Section XII SubCommittee on Transport Tanks, Vice Chairs the
Sub Group on General Requirements, and is a member of the
ASME Hydrogen Steering Committee, and various taskgroups.
Mr. Staniszewski is also a member of the National Board Inspection Code, Main Committee, Subgroups RB, and Nonmandatory
Appendices. He has experience in the international standards
arena through membership and participation as a governmental
technical expert to the United Nations and International Standards Organizations on various Technical Committees, Sub-Committees and Work-Groups on gas cylinders, cryogenic vessels
and Hydrogen technologies.
He has 10 years of varied experience in the private sector spanning tool & die, manufacturing, research and product development,
design, construction and inspection. Within the federal government
he has spent 20 years in the areas of mechanical/electrical/chemical
project engineering, management, inspection and enforcement
issues that affect hazardous materials/dangerous goods in national
and international commerce.
STEVENSON, JOHN D.
Dr. John D. Stevenson is a Senior Consultant for
J.D. Stevenson, Consulting Engineer Co. He has
extensive experience worldwide in the nuclear
power field where he served as a consultant to the
IAEA and several non U.S. utilities and consulting firms. He holds a Ph.D. in Civil Engineering
from Case Western Reserve University. He has
provided structural-mechanical consulting services to the nuclear
power industry in the U.S. and abroad for the past 35 years and
has been a member of various committees of ASME and B&PVC
Section III for the past 35 years. He is currently also a member of
several of American Society of Civil Engineers, American Nuclear
Society, and American Concrete Institute committees and consultant to government agencies dealing with the structural-mechanical
safety of nuclear facilities.
SUTHERLIN, RICHARD C.
Richard Sutherlin is the President of Richard
Sutherlin PE Consulting, LLC. He has over
40 years of experience in reactive and refractory
metals (titanium, zirconium, niobium and tantalum) in corrosion, welding, melting, R&D, Outside Fabrication, failure analysis and applications
engineering. Mr. Sutherlin holds a B.Sc. in Metallurgical Engineering from the Montana School of Mines, University of Montana. Mr. Sutherlin has taught classes in many locations
worldwide on the welding of reactive metals in addition to training classes on the corrosion, fabrication, safety, design, inspection
and the application of reactive metals in the chemical processing
industry. He has authored numerous technical papers and as well as
several major handbook chapters. He has performed many reactive
metal failure analyses and also holds several patents on the production of reactive metal products.
Mr. Sutherlin is a Registered Professional Engineer in the State
of Oregon. He serves on the ASME Boiler and Pressure code committees, Member of BPV II, Member of the BPV II Executive
committee, Chairman of BPV II Subgroup Non-ferrous alloys and
Member of BPV VIII, Sub-group of Materials. He is a member
of NACE (National Association of Corrosion Engineers). Richard
serves as Chairman of the American Welding Society A5K Subcommittee of Titanium and Zirconium Filler Metals, Chairman of
the G2D Subcommittee on Reactive Alloys and a member of the
AWS G2 – Committee on Joining Metals and Alloys and a member of the A5 – Committee on Filler Metals Materials.
SWAYNE, RICHARD W.
Mr. Swayne works for Reedy Engineering, Inc.
He has worked as a metallurgist, welding engineer, quality assurance manager, and consultant,
in the pressure vessel and piping industry, since
1975. He has experience in design, fabrication,
and operation of various power and refinery
plant components, including valve design and
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t xxxiii
application, welding and materials engineering, and quality assurance program management for construction and operation. He is
an expert and well-known instructor in inservice inspection, inservice testing, and repair/replacement programs in operating power
plants. He has assisted many organizations in preparation for new
and renewal ASME Certificates of accreditation and has participated in many ASME National Board Accreditation Surveys. Mr.
Swayne has been an active participant since 1977 as a member
of ASME and ASTM Codes and Standards Committees. He is
the Chair of the ASME Boiler and Pressure Vessel Committee
on Inservice Inspection of Nuclear Power Plants and a member
of several sub-tier committees. He is Vice Chair of Operations
for the ASME Council on Standards and Certification. He is a
member and past Chair of the ASME Board on Nuclear Codes
and Standards, and a member of the ASME Technical Oversight
Management Committee. Mr. Swayne is also a past member of the
Boiler and Pressure Vessel Standards Committee, the Subcommittee on Materials, and several working groups under the Subcommittee on Nuclear Power. He has served as a consultant to utilities,
architect/engineers, manufacturers, and material manufacturers
and suppliers. He has been a Qualified Lead Auditor, and a Qualified Level II Examiner in several nondestructive examination
methods. He has been involved in engineering reviews, material
selection and application, and quality assurance auditing.
SWEZY JR., JOHN P.
John has an Associate of Science from the University of the State of New York, with extensive
knowledge and expertise gained from his Navy
experience, military and civilian training, and
extensive self-study in the areas of welding, NDE,
and pressure equipment design.
John’s engineering career began as a Nuclear
Trained Machinists Mate in the “Silent Service”
of the US Navy onboard nuclear powered Submarines. Receiving an Honorable Discharge after 15½ years of active duty as
a Disabled Veteran, John entered civilian employment in 1990
as a National Board Commissioned Boiler and Pressure Vessel
Inspector, and served as an Authorized Inspector, Authorized
Inspector Supervisor, and as a Staff Technical Consultant for
ASME Accredited Authorized Inspection Agencies providing
Codes and Standards technical support to Authorized Inspectors,
Authorized Inspector Supervisors, and ASME Code Manufacturers around the world. John also began serving as an ASME Codes
and Standards volunteer on ASME Boiler and Pressure Vessel
Committees in 1996, and on ASME B31 Piping Committees in
2010.
Additionally, John served on the staff of UT Battelle at Oak
Ridge National Laboratory in Oak Ridge, TN as a Pressure Systems Engineer at the Spallation Neutron Source project, and as
a Mechanical Engineer in the Fabrication, Hoisting and Rigging
Division. He developed the inservice inspection program for pressure equipment at ORNL after achieving National Board accreditation for UT-Battelle, LLC as a Federal Inspection Agency.
In 2002, John recognized a need for economical and professional engineering design and consulting services, and started an
engineering consulting business under the name Boiler Code Tech,
LLC, providing responsive, professional engineering consulting
services to a wide variety of ASME Code pressure equipment
manufacturers. In December of 2013 this business became John’s
full time occupation.
UPITIS, ELMAR
Elmar Upitis received a B.S. degree in Civil
Engineering from University of Illinois in 1955
and did postgraduate studies at the Illinois Institute of Technology. He served in the US Army
and was employed by Chicago Bridge & Iron
Company from 1955 to 1995 in various capacities, including Chief Design Engineer, Manager
of Metals Engineering, and Senior Principal Engineer–Materials.
He was also responsible for oversight of CBI engineering in South
America, Europe and Africa and Middle East. Mr. Upitis provides
engineering consulting services in the areas of codes and standards
(ASME, API, ASTM, etc.), design of plate structures, fitness-forservice evaluation, and materials related issues. He is a licensed
professional and structural engineer in the State of Illinois, ASME
Fellow and a member of various technical committees in the
ASME B&P Vessel Code, ASTM Fellow and a member of several ASTM technical committees, former Chair of Pressure Vessel
Research Council (PVRC) and an active participant in the PVRC,
and a member of AWS and WRC. He is involved in the development of the new B&PV Code to replace the present Section VIII,
Division 2 and several other projects related to the ASME B & PV
Code.
Mr. Upitis is a co-author of WRC Bulletin 435 on design margins in ASME Section VIII, Divisions 1 and 2, WRC Bulletin 447
on evaluation of operating margins for in-service pressure equipment, WRC Bulletin 453 on minimum weld spacing requirements
for API Standard 653, PVRC report on the European Pressure
Equipment Directive, and several other published papers on Cr-Mo
steel pressure vessels.
VATTAPPILLY, JAYARAM
Jay holds a Mechanical Engineering degree from
the University of Calicut, India, a Master of Engineering degree in Welding from National Institute
of Technology (NIT), Tiruchirappalli, India and a
second Master’s degree in Advanced Design and
Manufacturing from the University of Waterloo,
Ontario, Canada.
Mr. Vattappilly provides technical support/code consulting on
ASME Boiler and Pressure Vessel Code Sections I, IV, VIII & IX.
He is HSB’s subject matter expert on the Indian Boiler Regulations
(IBR). He teaches Section VIII, I, IX, B31.1 and NBIC courses for
HSB’s clients and Inspectors. He also assists HSB with Design
Reviews.
Jay’s previous work experience has principally been in the
area of pressure equipment construction, working in the role of
a QA/QC Engineer, an Inspection Engineer for a large engineering consulting firm servicing refineries and petrochemical plants,
xxxiv t Contributor Biographies
a welding engineer responsible for both structural and pressure
vessel welding activity, and as a design engineer of pressure equipment constructed to ASME Sections I, IV, B31.1, and VIII.
Jay presently holds a Professional Engineering license from
Ontario, Canada and National Board Commission with “NS” &
“A” endorsements. He is the Chair of Subgroup on Design – BPV I
and a member of Committee on Power Boilers – BPV I. He is
also a member of the Subgroup on Design – BPV VIII, Subgroup
on Toughness – BPV VIII, Special Committee on InterpretationsBPV VIII and Subgroup on Materials – BPV I.
VOLLMER, RICHARD O.
Mr. Vollmer graduated with honors from Lehigh
University in Bethlehem, PA (BSME 1989), and
was elected to Tau Beta Pi and Pi Tau Sigma.
He has been a member of ASME since 1989,
and is a Registered Professional Engineer in the
Commonwealth of Pennsylvania. He is a member
of the ASME Working Group on Core Support
Structures (WG-CSS) and Working Group on
Design Methodology (WG-DM).
Mr. Vollmer has worked in the electric power industry since
1989, with expertise in the design and analysis of pressure vessels, valves, reactor internals, and power plant structures. He has
broad experience with nuclear industry codes & standards, including the ASME B&PV Code and U.S. naval nuclear design codes.
He is currently a Fellow Engineer specializing in advanced reactor
internals at Westinghouse Electric Corporation. Prior to joining
Westinghouse, Mr. Vollmer was a senior engineer at MPR Associates, providing consulting services to fossil and nuclear power
utilities and equipment vendors.
VOORHEES, STEPHEN V.
Employed in the Authorized Inspection Agency
sector since 1976 with Factory Mutual, Commercial Union Insurance Company, Hartford Steam
Boiler I and I, and OneBeacon America Insurance
Company. Duties have included inspection of all
types of boilers, pressure vessels, heat exchangers, nuclear components as well as supervision of
these activities and finally management of same.
Currently serves on Section IV Heating Boilers as Vice Chair,
Section XII, Transport Tanks as a member and Chair of Sub-Group
Fabrication and Inspection, and serve as member of the Standards
Committee.
From 1970 to 1974 served in the US Navy in the Western Pacific
on destroyers as a boiler technician.
Married to Louise for 25 years with two sons. Reside in Allentown, PA. Hobbies include hunting, shooting and golf.
WOODWORTH, JOHN I.
John I. Woodworth has BSME from Univ. of
Buffalo, 1948. He is engaged in consulting on
Steam and Hot Water (hydronic) heating systems
and Codes and Standards. He provides information for legal proceedings of hydronic heating
systems and equipment. He was previously with
Fedders Corp. (1948–1959), as Technical Director
of Hydronics Institute (predecessor Institute of Boiler and Radiator
Manufacturers), 1959–1990. Woodworth’s professional activities
1990 to date are supported by Hydronics Institute Division, GAMA.
He is a member of ASME, and a member of several ASME Code
Committees such as Section IV, (1967–date), Cast-Iron Subgroup;
Chair, ASME Section VI; Vice-Chair Controls and Safety Devices
for Automatically-Fired Boilers Standards Committee (1973–
2000). He was a consultant with the National Institute of Science
and Technology (formerly the National Bureau of Standards).
Woodworth is a Life Member of ASHRAE, Member of several of
its Technical Committees, Secretary, Vice Chair and Chair of SPC.
He has written numerous technical articles for trade magazines.
John received ASME Distinguished Service Award (1991), Dedicated Service Award (2000) and ASHRAE Standards Achievement Award (1996). He was a Member, National Fuel Gas Code
Committee, VP, Uniform Boiler and Pressure Vessel Laws Society
and Liaison to Building Energy Codes & Standards Committee. He
was a Member of technical advisory committees for Brook-haven
National Laboratories.
XU, KANG
Kang is currently the Pressure Vessel Consultant
in Praxair. He has a Ph.D. degree in materials engineering from Univ. of Maryland at College Park.
He has been working in the industrial gas industry in areas of pressure vessels, structural integrity
assessment, materials selections and failure analysis for 14 years. Before joining Praxair, he worked
as a senior engineer in the steel industry. His experience also extends
to fracture mechanics testing and analysis for aerospace and nuclear
industries. He serves in ASME Boiler and Pressure Vessel Code
Committees in Section VIII and Section XII. He is the Vice Chair of
Section II/VIII Subgroup on Toughness and the Secretary of Section
VIII Subgroup on Materials. He is also a member of NACE, ASTM
and CGA (Compressed Gas Association) technical committees. He
authored and co-authored 28 peer reviewed technical publications.
Contents
Dedication to the First Edition
Robert E. Nickel and William E. Cooper. . . . . . . . . . . . . . .iii
Dedication to the Fifth Edition
K. R. Rao. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv
Acknowledgements (to the First Edition) . . . . . . . . . . . .v
Acknowledgements (to the Second Edition) . . . . . . . . . v
Acknowledgements (to the Third Edition) . . . . . . . . . . .vi
Acknowledgements (to the Fourth Edition) . . . . . . . . .vii
1.5
Distinction between Boiler Proper Piping and
Boiler External Piping
1.6 How and Where Section I is Enforced and
Effective Dates
1.7 Fundamentals of Section I Construction
1.8 Future Changes
1.9 References
1.10 Design Exercises
Preface to the First Edition
K. R. Rao and Robert E. Nickell. . . . . . . . . . . . . . . . . . . . .xli
Preface to the Second Edition
K. R. Rao. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xlii
2.8
2.9
Preface to the Third Edition
K. R. Rao. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xliii
2.10
Contributor Biographies . . . . . . . . . . . . . . . . . . . . . . . . .ix
Preface to the Fourth Edition
K. R. Rao. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xliv
Preface to the Fifth Edition
K. R. Rao. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xlv
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xlvii
Organization and Operation of the ASME Boiler
and Pressure Vessel Code Committees . . . . . . . . . . . .lxi
CHAPTER 1 Introduction to Power Boilers
John R. MacKay, Ed Ortman and Jay Vattappilly. . . . . . .1-1
1.1
1.2
1.3
1.4
Introduction
History and Philosophy of Section I
The Organization of Section I
Scope of Section I: Pressure Limits
and Exclusions
1-1
1-1
1-3
1-8
1-14
1-16
1-35
1-36
1-37
CHAPTER 2 Section VII—Recommended Guidelines
for the Care of Power Boilers
William L. Lowry and James T. Pillow. . . . . . . . . . . . . . . 2-1
2.1
2.2
2.3
2.4
2.5
2.6
2.7
Acknowledgements (to the Fifth Edition) . . . . . . . . . . viii
1-13
2.11
2.12
2.13
2.14
2.15
2.16
2.17
2.18
2.19
2.20
2.21
2.22
Introduction - Chapter 2
Introduction - Section VII
Fundamentals of Watertube Boilers - Article 100
Boiler Operation—Article 101
Boiler Auxiliaries—Article 102
Appurtenances—Article 203
Instrumentation, Controls, and Interlocks—
Article 104
Examinations—Article 105
Repairs, Alterations, and Maintenance—
Article 106
Protecting Heat Transfer Surfaces—
Article 200
Preventing Boiler Failures—Article 201
Documents, Records, and References
Firetube Boilers, Article 300
Electric Steam Boilers, Article 301
Utility Boilers, Article 302
Stoker-Fired Boilers, Article 400
Pulverized-Coal-Fired Boilers, Article 401
Ash Removal, Article 402
Maintenance, Article 403
Glossary
Final Notes
References
2-1
2-2
2-3
2-9
2-15
2-17
2-23
2-24
2-26
2-27
2-30
2-32
2-32
2-32
2-32
2-32
2-32
2-32
2-32
2-33
2-33
2-34
CHAPTER 3 Part 2, Section II—Materials and
Specifications
Elmar Upitis, Richard A. Moen, Marvin L. Carpenter,
William Newell Jr., John F. Grubb, Richard C. Sutherlin,
Jeffrey Henry, C. W. Rowley and Anne Chaudouet. . . . . 3-1
3.1
History of Materials in the ASME Boiler and
Pressure Vessel Code
3-1
xxxvi t Contents
3.2
3.3
3.4
3.5
3.6
Basis for Acceptance of Materials for Code
Construction—Section II, Part A: Ferrous
Material Specifications
Basis for Acceptance of Materials for Code
Construction—Section II, Part B: Nonferrous
Material Specifications
Section II, Part C: Specification for Welding
Rods, Electrodes, and Filler Metals
Basis for Acceptance of Materials for Code
Construction—Section II, Part D: Properties
Basis for Acceptance of Material for Code
Constructions—Section II, International Material
Specifications
3-7
3-13
3-27
3-74
3-91
CHAPTER 4 A Commentary for Understanding
and Applying the Principles of the ASME Boiler
and Pressure Vessel Code
Roger F. Reedy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
4.1
4.2
4.3
4.4
4.5
4.6
4.7
4.8
4.9
4.10
4.11
4.12
4.13
4.14
4.15
4.16
4.17
4.18
4.19
4.20
4.21
4.22
4.23
4.24
4.25
4.26
4.27
Introduction
Design Factors Used in the ASME Code
Design Specifications and Design Reports
Section III versus Section VIII
Design Life and Commutative-Usage Factors
Service-Level Loadings
Seismic Evaluations
Engineers, Design, and Computers
Nuclear Containment Vessels
Tolerances, Significant Figures, and Nominal
Dimensions
Corrosion and Erosion
Forming Operations
Post–Weld Heat Treatment
Nondestructive Examination
Hydrostatic Test
Quality Assurance
Design Loadings and Stresses Compared
to Actual Conditions
Post-Construction Postulated Loadings
and Stresses
Maintenance of Design Margins
Thermal Relief Devices
Code Cases
ASME Interpretations
Code Simplification
Future Considerations for Cyclic Service
New ASME Code–2007 Edition of
Section VIII, Division 2
Summary
References
4-1
4-3
4-5
4-6
4-6
4-6
4-7
4-7
4-8
4-8
4-9
4-9
4-10
4-10
4-10
4-11
4-12
4-13
4-14
4-14
4-14
4-14
4-14
4-15
4-15
4-17
4-17
CHAPTER 5 Subsection NCA—General
Requirements for Division 1 and Divi.sion 2
Richard W. Swayne. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5.1
5.2
5.3
5.4
5.5
5.6
Introduction
5-1
Article NCA-1000 Scope of Section III
5-1
Article NCA-2000 Classification of Components
and Supports
5-4
Article NCA-3000 Responsibilities and Duties
5-6
Article NCA-4000 Quality Assurance
5-21
Article NCA-5000 Authorized Inspection
5-26
5.7
5.8
5.9
Article NCA-7000 Reference Standards
Article NCA-8000 Certificates, Nameplates,
Code Symbol Stamping, and Data Reports
Article NCA-9000 Glossary
5-28
5-28
5-34
CHAPTER 6 Subsection NB—Class I Compo.nents
David P. Jones and Chakrapani Basavaraju. . . . . . . . . . 6-1
6.1
6.2
6.3
6.4
6.5
6.6
6.7
6.8
6.9
6.10
Introduction
Design
Analysis
Primary Stress Limits
Primary-Plus-Secondary Stress Limits
Fatigue
Special Procedures
Elastic-Plastic FEA
References
Summary of Changes
6-1
6-4
6-7
6-12
6-21
6-25
6-32
6-44
6-44
6-46
CHAPTER 7 Section III: Subsections NC and ND—
Class 2 and 3 Components
Chakrapani Basavaraju and Marcus N. Bressler. . . . . . . 7-1
7.0
7.1
7.2
7.3
7.4
Introduction to Chapter 7.0
Articles NC-1000 and ND-1000
Articles NC-2000 and ND-2000, Material
Articles NC-3000 and ND-3000 (Design)
Articles NC-4000 and ND-4000 (Fabrication
and Installation)
7.5 Articles NC-5000 and ND-5000 (Examination)
7.6 Articles NC-6000 and ND-6000 (Testing)
7.7 Articles NC-7000 and ND-7000 (Overpressure
Protection)
7.8 Articles NC-8000 and ND-8000 (Nameplate,
Stamping, and Reports)
7.9 Summary of Changes
7.10 Summary of Changes
7.11 References
7.12 Summary of Changes (2015 and 2013 Code
Editions)
7-1
7-2
7-4
7-9
7-30
7-32
7-34
7-34
7-35
7-40
7-42
7-45
7-46
CHAPTER 8 Subsection NB, NC, ND-3600 Piping
Mark A. Gray and Jack R. Cole . . . . . . . . . . . . . . . . . . . .8-1
8.1
8.2
8.3
8.4
8.5
8.6
8.7
Background
Nuclear Class 1, NB-3600
Nuclear Class 2 and 3 NC/ND-3600
Design Process
Design Specification Discussion
Recommendations for Code Committee
References
CHAPTER 9
8-1
8-2
8-17
8-23
8-26
8-27
8-27
Subsection NE—Class MC Components
Roger F. Reedy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1
9.1
9.2
9.3
9.4
9.5
9.6
9.7
Introduction
Scope of Subsection NE
Boundaries of Jurisdiction of Subsection NE
General Material Requirements
Certified Material Test Reports
Material Toughness Requirements
General Design Requirements
9-1
9-1
9-1
9-5
9-6
9-7
9-9
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t xxxvii
9.8
9.9
9.10
9.11
9.12
9.13
9.14
9.15
9.16
9.17
9.18
9.19
9.20
9.21
9.22
9.23
9.24
9.25
9.26
9.27
9.28
9.29
9.30
9.31
9.32
9.33
9.34
Qualifications of Professional Engineers
Owner’s Design Specifications
Certified Design Report
Design by Analysis
Appendix F
Fatigue Analysis
Buckling
Reinforcement of Cone-to-Cylinder Junction
Plastic Analysis
Design by Formula
Openings
Bolted Flange Connections
Welded Connections
General Fabrication Requirements
Tolerances
Requirements for Weld Joints
Welding Qualifications
Rules for Marking, Examining,
and Repairing Welds
Heat Treatment
Examination
Qualifications and Certification of NDE Personnel
Testing
Overpressure Protection
Nameplates, Stamping, and Reports
Recommendations
References
Summary of Changes
9-9
9-10
9-10
9-10
9-11
9-12
9-13
9-14
9-15
9-15
9-15
9-16
9-16
9-17
9-18
9-18
9-18
9-19
9-19
9-20
9-22
9-22
9-22
9-23
9-23
9-23
9-23
CHAPTER 10 Subsection NF—Supports
Uma S. Bandyopadhyay. . . . . . . . . . . . . . . . . . . . . . . . .10-1
10.1
10.2
10.3
10.4
10.5
10.6
10.7
10.8
10.9
10.10
10.11
10.12
Executive Summary
NF-1000 Introduction
NF-2000 Materials
NF-3000 Design
NF-4000 Fabrication and Installation
NF-5000 Examination
NF-8000 Nameplates, Stamping, and Reports
NF Appendices
Code Cases and Interpretations
Summary of Changes
ASME B31.1 and B31.3 Supports
References
10-1
10-1
10-6
10-14
10-28
10-29
10-31
10-32
10-34
10-35
10-35
10-37
CHAPTER 11 Subsection NG—Core Support
Structures
Richard O. Vollmer. . . . . . . . . . . . . . . . . . . . . . . . . . . . .11-1
11.1
11.2
11.3
11.4
11.5
11.6
11.7
11.8
11.9
11.10
11.11
11.12
11.13
Introduction
Definition of Core Support Structures (NG-1120)
Jurisdictional Boundaries (NG-1130)
Unique Conditions of Service
Materials of Construction (NG-2000)
Special Materials
Design (NG-3000)
Fabrication and Installation (NG-4000)
Examination (NG-5000)
Testing
Overpressure Protection
Nameplates/Stamping Effects (NG-8000)
Environmental Effects (NG-3124)
11-1
11-3
11-4
11-4
11-5
11-6
11-6
11-15
11-17
11-19
11-19
11-19
11-19
11.14
11.15
11.16
11.17
11.18
11.19
11.20
11.21
11.22
Special Bolting Ments (NG-3230)
Code Cases (NCA-1140)
Interpretations for Subsection NG
Elevated Temperature Applications
Additional Considerations
Beyond the State-of-the-Art
References
Abbreviations and Nomenclature
Summary of Changes
11-19
11-20
11-20
11-22
11-22
11-23
11-25
11-25
11-25
CHAPTER 12 Nonmetallic Pressure Piping System
Components
C. Wesley Rowley and Thomas M. Musto . . . . . . . . . . .12-1
Part A. Experience with Nonmetallic Materials in
Structural/Pressure Boundary Applications
12A.1 Introduction
12A.2 Types of Nonmetallic Materials
12A.3 Design Specification
12A.4 Nonmetallic Components
12A.5 Joining of Nonmetallic Components
(and Sub-Components)
12A.6 Application Problems
12A.7 Quality Assurance (QA)
12A.8 Sensitive Aspects of Nonmetallic Fabrication
Processes
12A.9 Conclusions
Part B. NM-1, Construction Standard for
Thermoplastic Pressure Piping Systems
12B.1
12B.2
12B.3
12B.4
12B.5
12B.6
12B.7
12B.8
Introduction
Design
Materials
Standard for Piping Components
Fabrication, Assembly, and Erection
Inspection, Examination, and Testing
Metallic Piping Lined with Thermoplastics
Multilayered Reinforced Thermoplastic
Piping Systems
12-2
12-2
12-2
12-3
12-4
12-5
12-6
12-8
12-8
12-9
12-9
12-9
12-10
12-11
12-12
12-12
12-12
12-13
12-13
Part C. Construction Standard for Fiber-Reinforced
Thermoset-Plastic (FRP) Pressure
Piping Systems
12-13
12C.1
12C.2
12C.3
12C.4
12C.5
12C.6
12C.7
12C.8
Introduction
Design
Constituent Materials
Standard for Piping Components
Fabrication, Assembly, and Erection
Inspection, Examination, and Testing
Mandatory Appendices
Nonmandatory Appendices
12-13
12-14
12-14
12-15
12-15
12-15
12-18
12-19
Part D. Nonmetallic Materials
12-19
12D.1
12D.2
12D.3
12D.4
12D.5
12-19
12-19
12-19
12-19
12D.6
12D.7
Introduction
Thermoplastic Specifications
Potential Future Thermo Plastic Specifications
Thermoset Plastic Specifications
Potential Future Thermoset
Plastic Specifications
Other Nonmetallic Materials
Physical Material Properties
12-22
12-22
12-22
xxxviii t Contents
12D.8
12D.9
Engineering Material Properties
Allowable Stress and Physical Property
Tables and Data Sheets
12D.10 Thermoplastic Property Performance
12D.11 Thermoset Plastic Property
Performance
12D.12 References
CHAPTER 13
12-23
12-23
12-23
12-23
12-24
Nuclear Pumps
Robert E. Comman, Jr. and Ross R. Klein . . . . . . . . . . 13-1
13.1
13.2
13.3
13.4
13.5
13.6
13.7
13.8
13.9
13.10
Introduction
General Section III Requirements
Specific Pump Requirements
General Requirements for Class 1 Pumps
NC-3400 Class 2 Pumps
ND-3400 Class 3 Pumps
General Requirements for Class 2 and 3 Pumps
Changes in Future Code Editions
References
Additional Documents of Interest
CHAPTER 14
13-1
13-1
13-3
13-4
13-4
13-7
13-7
13-8
13-8
13-8
Nuclear Valves
14.5
14.6
14.7
14.8
Introduction
General Section III Requirements
Specific Valve Requirements
NC-3500 and ND-3500, Class 2
and Class 3 Valves
Changes in the 2013 & 2015 Editions
Other Valve Standards
References
Additional Documents of Interest
CHAPTER 15
14-1
14-2
14-3
14-11
14-12
14-14
14-14
14-14
Code for Concrete Containments
Arthur C. Eberhardt, Clayton T. Smith, Michael F.
Hessheimer, Ola Jovall, and Christopher A. Jones . . . .15-1
15.1 Introduction
15.2 Future Containment Development
15.3 Background Development of Concrete
Containment Construction Code Requirements
15.4 Reinforced-Concrete Containment Behavior
15.5 Concrete Reactor Containment Design
Analysis and Related Testing
15.6 Code Design Loads
15.7 Allowable Behavior Criteria
15.8 Analytical Models and Design Procedures
15.9 Special Design Features
15.10 Current Organization of the Code
15.11 Article CC-4000: Fabrication
and Construction
15.12 Article CC-5000: Construction Testing and
Examination
15.13 Article CC-6000: Structural Integrity Test
of Concrete Containments
15.14 Article CC-7000: Overpressure Protection
15.15 Article CC-8000: Nameplates, Stamping,
and Reports
15-1
15-7
15-8
15-11
15-12
15-13
15-13
15-13
15-13
15-14
15-18
15-18
15-18
15-19
15-19
15-19
15-22
15-24
15-25
CHAPTER 16 Containments for Transportation
and Storage of Spent Nuclear Fuel and High-Level
Radioactive Material and Waste
D. Keith Morton and D. Wayne Lewis . . . . . . . . . . . . . . 16-1
16.1
16.2
16.3
16.4
16.5
16.6
16.7
16.8
16.9
16.10
Guy A. Jolly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-1
14.1
14.2
14.3
14.4
15.16 Practical Nuclear Power Plant Containment
Designed to Resist Large Commercial Aircraft
Crash and Postulated Reactor Core Melt
15.17 Items Which Should be Considered in Future
Revisions of the Code
15.18 Summary
15.19 References
16.11
16.12
16.13
16.14
16.15
Introduction
Historical Development
Scope of Subgroup Nupack
Code Development
General Provisions
Specified Loading Categories
Allowable Stress
Materials Fabrication, Installation,
Examination, and Testing
Code Text Organization
Incorporation of Strain-Based Acceptance
Criteria—A Major Change
Current Activities in Division 3
Interaction with Section XI and the Proposed
ISI Code Case for Storage Containments
Suggested Enhancements for the Future
References
Summary of Changes
16-1
16-1
16-2
16-2
16-2
16-3
16-3
16-5
16-5
16-8
16-9
16-10
16-10
16-11
16-11
CHAPTER 17 Division 5—High Temperature Reactors
Robert I. Jetter and D. Keith Morton . . . . . . . . . . . . . . . 17-1
17.1
17.2
17.3
17.4
17.5
Introduction
Scope
Background
Organization of Division 5
Graphite General Requirements and Design/
Construction Rules
17.6 Future Expectations
17.7 Summary
17.8 References, Including Annotated
Bibliographical Notations
17-1
17-1
17-1
17-2
17-37
17-42
17-43
17-43
CHAPTER 18 ASME Section IV: Rules for the
Construction of Heating Boilers
Clayton T. Smith. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18-1
18.1 Introduction
18.2 Part HG: General Requirements for
All Materials of Construction
18.3 Part HF: Requirements for Boilers Constructed
of Wrought Materials
18.4 Part HF, Sub-part HW: Requirements
for Boilers Fabricated by Welding
18.5 Part HF, Sub-part HB: Requirements for
Boilers Fabricated by Brazing
18.6 Part HC: Requirements for Boilers
Constructed of Cast Iron
18-1
18-4
18-27
18-32
18-36
18-37
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t xxxix
18.7 Rules of Part HA: Hot Water Heating Boilers
Constructed Primarily of Cast Aluminum
18.8 Part HLW: Requirements for Potable-Water
Heaters
18.9 Considerations Likely to be in Future Code
Editions
18.10 What Should the ASME Code Committees
and Regulators Consider, Recognizing the
Intent of the ASME B&PV Code?
18.11 References
18-42
18-44
18-56
18-56
18-56
CHAPTER 19 ASME Section VI: Recommended
Rules for the Care and Operation of Heating
Boilers
Clayton T. Smith. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19-1
19.1
19.2
19.3
19.4
19.5
19.6
19.7
19.8
19.9
19.10
19.11
19.12
19.13
19.14
19.15
Introduction
General
Types of Boilers
Accessories
Installation
Fuels
Fuel-Burning Equipment and Fuel-Burning
Controls
Boiler-Room Facilities
Operation, Maintenance, and Repair
of Steam Boilers
Operation, Maintenance, and Repair of
Hot-Water-Supply and Hot-Water-Heating
Boilers
Water Treatment
General Comment
Considerations Likely to be in Future Code
Editions
Summary of Changes
Reference
19-1
19-2
19-7
19-10
19-14
19-18
19-19
19-22
19-23
19-30
19-35
19-38
19-38
19-39
19-39
CHAPTER 20
Nondestructive Examination (NDE)
Jon E. Batey and G. Wayne Hembree . . . . . . . . . . . . . .20-1
20.1
20.2
20.3
20.4
20.5
20.6
20.7
20.8
20.9
20.10
20.11
20.12
20.13
20.14
20.15
20.16
20.17
20.18
20.19
20.20
20.21
20.22
20.23
20.24
20.25
20.26
20.27
Introduction
History
Organization of Section V
Relation to Other ASME Code Book Sections
Article 1: General Requirements
Article 2: Radiographic Examination
Article 4: Ultrasonic Examination Methods
for Welds
Ultrasonic Examination Methods for Materials
Article 6: Liquid-Penetrant Examination
Article 7: Magnetic-Particle Examination
Article 8: Eddy-Current Examination
Article 9: Visual Examination
Article 10: Leak Testing
Acoustic Emission Examination
Article 11: Acoustic Emission Examination
of Fiber-Reinforced Plastic Vessels
Article 12: Acoustic Emission Examination
of Metallic Vessels During Pressure Testing
Article 13: Continuous AE Monitoring
Article 14: Examination System Qualification
Article 15: Alternating Current Field
Measurement
Article 16: Magnetic Flux Leakage
Article 17: Remote Field Testing
Article 18: Acoustic Pulse Reflectometry
(APR) Examination
Article 19: Guided Wave Examination Method
for Piping
Technical Changes to Section V
Future Changes Anticipated for Section V
Acknowledgements
References
20-1
20-1
20-2
20-3
20-4
20-6
20-11
20-16
20-16
20-18
20-19
20-20
20-21
20-21
20-22
20-22
20-23
20-23
20-23
20-24
20-24
20-24
20-24
20-25
20-25
20-25
20-25
Preface to the First Edition
This book provides “The Criteria and Commentary on Select
Aspects of ASME Boiler and Pressure Vessel and Piping Codes”
in two volumes. The intent of this book is to serve as a “Primer” to
help the user weave through varied aspects of the ASME Codes and
B31.1 and B31.3 Piping Codes and present a summary of specific
aspects of interest to users. In essence, this Primer will enable users
to understand the basic rationale of the Codes as deliberated and
disseminated by the ASME Code Committees. This book is different from the Code Cases or Interpretations of the Code, issued
periodically by these ASME Code Committees, although these are
referred in the book. It is meant for a varied spectrum of users
of Boiler and Pressure Vessel (B&PV) and B31.1 and B31.3 Piping Codes in United States and elsewhere in the world. This book
should be considered as a comprehensive guide for ASME B&PV
Code Sections I through XI, B31.1 and B31.3 Piping Codes. The
contents of these two volumes can be considered as a companion
book—a criteria document—for the latest editions of the Code,
written by thirty-six professionals with expertise in its preparation
and use.
ASME and the industry volunteers have invested immense
resources in developing Codes and Standards for the Power and
Petrochemical Industry, including nuclear, non-nuclear, fossil,
and related. The industry has been relying on these documents,
collectively referred to as the ASME Code, on a day-today
basis, and regulators consult them for enforcing the rules. Research
and development, in both the material science and analytical areas,
find their results in the revisions and updates of the Codes. Over
a period of time, these B&PV and Piping Codes, encompassing
several disciplines and topics, have become voluminous Standards
that belie the intent and expectations of the authors of the Codes.
In a word, the B&PV Codes can become a “labyrinth” for an occasional user not conversant with the information contained in the
Code. Thus, given the wealth of information contained in the Code,
these cannot be easily discerned. For example, the B&PV Code,
even though it is literally an encyclopedia of rules and standards to
be followed by engineers in the nuclear or fossil or related industries, is not easy to comprehend and conform to. Alphanumeric text
and graphics are loaded with information, arrived at by a consensus
process from the deliberations of practicing engineers, professionals, academia, and regulators meeting several times a year. A lack
of understanding of the Code, therefore, can cause not only professional errors but also misplaced confidence and reliance on the
engineer’s interpretation that could lead to serious public safety
hazards. Spread over several volumes and thousands of pages of
text, tables, and graphics, it is not easy to decipher the criteria and
the basis of these Codes.
Thus, given the importance of these ASME Codes related to
the industry and the attendant technological advances, it becomes
a professional expediency to assimilate and appropriately apply the
wealth of information contained in the Codes. The first step, then,
is to ask, “Where is what?” The Code is spread over eleven Sections; attending the tutorials is one way to understand first-hand the
various Sections of the Code. However, this is not within the reach
of all of the engineers in the industry. The next best solution is to
have expert authors, versatile in the individual Sections and Subsections, to make the subject matter understand-able to the practicing engineers in a book format such as “A PRIMER.”
In this book, all of the Sections I through XI of the B&PV and
B31.1 and B31.3 Piping Codes are summarily addressed with
examples, explanatory text, tables, graphics, references, and annotated bibliographical notes. This permits engineers to more easily refer to the material requirements and the acceptance criteria
whether they are in the design basis or in an operability situation of
a nuclear plant or process piping. In addition, certain special topics of interest to engineers are explicitly addressed. These include
Rules for Accreditation and Certification; Perspective on Cyclic,
Impact, and Dynamic Loads; Functionality and Operability Criteria; Fluids; Pipe Vibration; Stress Intensification Factors, Stress
Indices, and Flexibility Factors; Code Design and Evaluation
for Cyclic Loading; and Bolted-Flange Joints and Connections.
Important is the inclusion of unique Sections such as Sections I, II,
IV through VII, IX, and X that enriches the value of the book as a
comprehensive companion guide for B&PV and Piping Codes. Of
considerable value is the inclusion of an in-depth treatment of Sections III, VIII, and XI. A unique aspect of the book chapters related
to the Codes is the treatment of the ori-gins and the historical background unraveling the original intent of the writers of the Criteria
of the Codes and Standards. Thus, the current users of these Codes
and Standards can apply their engineering knowledge and judgment intelligently in their use of these Codes and Standards.
Although these two volumes cannot be considered to be a perfect symphony, the subject matter orchestrates around a central
theme, that is, “The Use of B&PV and Piping Codes and Standards.” Special effort is made by the contributors, who are experts in
their respective fields, to cross-reference other Sections; this facilitates identifying the interconnection between various B&PV Code
xlii t Preface
Sections, as well as the B31.1 and B31.3 Piping Codes. The Table
of Contents, indexing, and annotated notes for individual Chapters
are provided to identify the connection between varied topics. It
is worth mentioning that despite the chapters not being of equal
length, comprehensive coverage is ensured. The coverage of some
sections is intentionally increased to provide in-depth discussion,
with examples to elucidate the points citing the Code Subsections
and Articles.
K. R. Rao, Ph.D., P.E.
Editor
Robert E. Nickell, Ph.D.
1999–2000 President
ASME International
Preface to the Second Edition
This edition continues to address the purpose of the first edition
to serve as a “Primer” to help the user weave through varied aspects
of the ASME Codes and B31.1 and B31.3 Piping Codes and present a summary of specific aspects of interest to users. In providing
the “end user” all of these aspects, the first edition has been revised
appropriately to be consistent with the current 2004 Codes.
Contributors of the first and second volumes had taken immense
pains to carefully update their write-ups to include as much of the
details that they could provide. Significant changes can be seen in
Sections II, III, VIII and XI with repercussions on Sections I, IV, V,
VII, IX and X. Thus, these consequences had been picked up by the
contributors to bring their write-up up-to-date. Similarly changes of
Power Piping (B31.1 Code) and B31.3 (Process Piping) have also
been updated.
Included in this edition is a third volume that addresses the critical issues faced by the BWR and PWR Nuclear facilities such
as BWR Internals, PWR Reactor Integrity, and Alloy 600 related
issues. With the aging of the Nuclear Plants, the regulators perspective can be meaningful, and this has been addressed by experts
in this area. In today’s industrial spectrum the role of Probabilistic
Risk Analysis has taken an important role and this volume has a
chapter contributed by recognized authorities. With the increased
use of computer–related analytical tools and with ASME Codes
explicitly addressing them, a chapter has been devoted to the
Applications of Elastic Plastic Fracture Mechanics in ASME Section XI Code.
ASME Codes are literally used around the world. More importantly the European Community, Canada, Japan and UK have been
increasingly sensitive to the relevance of ASME Codes. In this second edition, experts conversant with these country Codes had been
invited to detail the specifics of their Codes and cross-reference
these to the ASME Codes.
Public Safety, more so than ever before, has become extremely
relevant in today’s power generation. Experts hade been invited to
provide a perspective of the regulations as they emerged as well
as discuss the salient points of their current use. These include
the transportation of radioactive materials and the new ASME
Section XII Code, Pipe Line Integrity and pertinent topics involved
in decommissioning of nuclear facilities.
K. R. Rao, Ph.D., P.E.
Editor
Preface to the Third Edition
This edition continues to address the purpose of the previous editions to serve as a “Primer” to help the user weave through varied
aspects of the ASME Codes and B31.1 and B31.3 Piping Codes,
in addition to a discussion of “The Criteria and Commentary on
Select Aspects of ASME Boiler and Pressure Vessel and Piping
Codes” of interest to “end users”. This publication has been revised
in providing all of the aspects of the previous editions, while updating to the current 2007 Codes, unless otherwise mentioned. This
book in three volumes strives to be a comprehensive ‘Companion
Guide to the ASME Boiler and Pressure Vessel Code’.
Since the first edition, a total of 140 authors have contributed
to this publication, and in this edition there are 107 contributors
of which 51 are new authors. Several of the new contributors are
from countries around the world that use ASME B&PV Codes,
with knowledge of ASME Codes, in addition to expertise of their
own countries’ B&PV Codes. All of these authors who contributed
to this third edition considerably updated, revised or added to the
content matter covered in the second edition to address the current
and futuristic trend as well as dramatic changes in the industry.
The first two volumes covering Code Sections I through XI
address organizational changes of B&PV Code Committees and
Special topics relating to the application of the Code. Considering
significant organizational changes are taking place in ASME that
reflect the industry’s demands both in USA and internationally,
the salient points of these have been captured in this publication by
experts who have first hand information about these.
Volume 1 covers ASME Code Sections I through VII, B31.1 and
B31.3 Piping Codes. Continuing authors have considerably updated
the text, tables, and figures of the previous edition to be in line with
the 2007 Code, bringing the insight knowledge of these experts in
updating this Volume. Fresh look has been provided by new authors,
who in replacing previous contributors of few chapters, have provided an added perspectives rendered in the earlier editions. In one
case, the chapter had been entirely rewritten by new experts, with a
new title but addressing the same subject matter while updating the
information to the 2007 ASME Code Edition.
ASME Code Committees have spent time and considerable
resources to update Section VIII Division 2 that was completely
rewritten in the 2007 Code Edition, and this effort has been captured in Volume 2 by several experts conversant with this effort.
Volume 2 has chapters addressing Code Sections VIII through XI,
refurbished with additional code material consistent with the current 2007 Code edition. Notable updates included in this Volume
relate to maintenance rule; accreditation and certification; perspectives on cyclic, impact and dynamic loads; functionality and operability criteria; fluids; pipe vibration testing and analysis; stress
intensification factors, stress indices and flexibility factors; Code
design and evaluation for cyclic loading; and bolted-flange joints,
connections, code design and evaluation for cyclic loading for
Code Sections III, VIII and a new chapter that discusses Safety
of Personnel using Quick-actuating Closures on Pressure Vessels
and associated litigation issues. While few chapters have been
addressed by new authors who added fresh perspective, the efforts
of continuing authors have provided their insights with additional
equations, figures and tables in addition to extensive textual matter.
The third volume of this edition is considerably enlarged to
expand the items addressing changing priorities of Codes and
Standards. Continuing authors who addressed these topics in the
previous edition have discussed these with respect to the ASME
2007 Code Edition. The discussions include chapters on BWR
and PWR Reactor Internals; License Renewal and Aging Management; Alloy 600 Issues; PRA and Risk-Informed Analysis; ElasticPlastic Fracture Mechanics; and ASME Code Rules of Section XII
Transport Tank Code. Chapters covering ‘U.S. Transportation
Regulations for Radioactive Materials’; ‘Pipeline Integrity and
Security’, and ‘Decommissioning of Nuclear Facilities’ have been
considerably revised.
In Volume 3 experts around the world capture ‘Issues Critical
for the Next Generation of Nuclear Facilities’ such as Management
of Spent Nuclear Fuel, Generation III1 PWRs, New Generation
of BWRs and VERY High Temperature Generation IV Reactors.
The impact of globalization and inter-dependency of ASME
B&PV Codes had been examined in the previous edition in European Community, Canada, France, Japan and United Kingdom.
Contributors who authored these country chapters revisited their
write-up and updated to capture the current scenario.
Significant contribution in the third volume is the inclusion of
additional countries with changing priorities of their Nuclear Facilities. In-depth discussions cover the international experts of these
countries which own and operate nuclear reactors or have nuclear
steam supply vendors and fabricators that use ASME B&PV Code
Sections I through XII. This information is meant to benefit international users of ASME Codes in Finland, Belgium, Germany,
Spain, Czech and Slovakia, Russia, South Africa, India, Korea and
Taiwan that have been added in this third edition.
A unique feature of this publication is once again, as in the previous editions, the inclusion of all author biographies and an introduction that synthesizes every chapter, along with an alphabetical
listing of indexed terms.
K. R. Rao, Ph.D., P.E.
Editor
Preface to the Fourth Edition
This edition continues to address the purpose of the previous
editions to serve as a “Primer” to help the user weave through varied aspects of the ASME Codes and B31 Piping Codes, in addition to a discussion of “The Criteria and Commentary on Select
Aspects of ASME Boiler and Pressure Vessel and Piping Codes”
of interest to “end users”. This publication has been revised in providing all of the aspects of the previous editions, while updating
to the current 2010 Codes, unless otherwise mentioned. This book
strives to be a comprehensive ‘Companion Guide to the ASME
Boiler and Pressure Vessel Code’.
All of the 48 authors who contributed to 38 Chapters in this
fourth edition considerably updated, revised or added to the content matter covered in the third edition to address the current and
future trends as well as dramatic changes in the industry. Unlike
the previous third edition, this edition has two volumes dedicated
entirely to the ASME Boiler and Pressure Vessel Code Sections I
through XII.
Not only have chapters of the third edition altered but the
restructuring of chapters made it possible for a smoother flow of
chapters relating to Sections I through XII that proceed B31 Piping
Codes appearing in Volume 2. Chapters not covering Code Section I through XII which were in Volume 2 of third edition have
been dropped from this fourth edition, and consequently chapters
of third edition have been renumbered. In this edition pagination of
chapters is different from the previous editions, starting from page
1 and ending with the last page of the chapter.
Considering significant organizational changes taking place in
ASME that reflect the industry’s demands both in USA and internationally, the salient points of these have been captured in both
the volumes by experts who have first hand information about
these. Each of the volumes 1 and 2 have Index provided at the end
of each volume as a quick reference to topics occurring in different
Code Sections of that volume.
Volume 1 covers ASME Code Sections I through VII, and Volume 2 addresses ASME Code Sections VIII through XII. In several
instances continuing authors, in some cases replacement authors
have considerably updated the text, tables, and figures of the previous edition to be in line with the 2010 Code, bringing the insight
knowledge of these experts in updating the previous edition. Fresh
look has been provided by new authors, who in replacing previous
contributors of few chapters, have provided an added perspectives
rendered in the earlier editions. In certain cases, the chapters had
been entirely rewritten by replacement experts, with new titles but
addressing the same topics while revising in its entirety and updating the information to the 2010 ASME Code Edition.
Volume 1 has chapters 3 and 15 covering Code Sections II and
Section III Division 2, respectively that have additional experts
to address topics which had not been covered in the third edition.
An additional chapter to cover Code Section III Division 5 has
been included in this third edition by experts conversant with Code
Committee activity. Other chapters covering the updates of Code
Sections I, III Divisions 1, 2 and 3, Section IV, V and VI have been
completely updated to ASME 2010 Code.
Volume 2 has chapters addressing Code Sections VIII through
XII with additional code material consistent with the current 2010
Code edition. Notable updates relating to Section VIII are chapters
covering Divisions 1, 2 and 3 and chapter dealing with “Safety of
Personnel”. ASME Section IX has been updated by a Code expert
since the initial rendering in the first edition. Code Section X has
been addressed by an expert replacing the original author with
considerable changes. Code Section XI that is perhaps crucial for
operating nuclear plants has been reorganized consistent with the
current trends with expert authors who are members of the respective committees who updated the chapters with 2010 Code. A significant addition in this edition is the retention of a chapter from the
third edition pertaining to Elastic-Plastic Mechanics in Section XI.
Unique for this fourth edition is the addition of several B31 Piping Codes and Standards in Part 11 dealt by new authors covering
B31.9 Building Services and ASME Standards For Piping; B31T
Standard For Toughness Requirements For Piping; B31.5: Refrigeration Piping and Heat Transfer Components; B31E Standard
for Seismic Design and Current ASME Edition Retrofit of above
Ground Piping Systems; B31J Standard for Test Method for Determining Stress I- Factors for Metallic Piping Components; B31.4
Standard for Pipeline Transportation Systems for Liquid Hydrocarbons and Other Liquids; B31.11 Standard for Slurry Transportation Piping; B31G: Manual for Determining the Remaining
Strength of Corroded Pipelines and B31Q: Qualification of Pipeline Operators; and B31.12: Hydrogen Piping and Pipelines.
K. R. Rao, Ph.D., P.E.
Editor
PREFACE TO THE FIFTH EDITION
This edition continues to address the purpose of the previous
editions to serve as a “Primer” to help the user weave through varied aspects of the ASME Codes and B31 Piping Codes, in addition to a discussion of “The Criteria and Commentary on Select
Aspects of ASME Boiler and Pressure Vessel and Piping Codes”
of interest to “end users”. This publication has been revised in providing all of the aspects of the previous editions, while updating to
the current 2015 Codes and topics pertinent to 2017 B&PV Code.
This book strives to be a comprehensive Companion Guide to the
ASME Boiler and Pressure Vessel Code.
This fully updated and revised fifth edition of this classic reference work has addressed in 40 chapters ASME 2015 Boiler Pressure Vessel & Piping Codes and Standards, whereas the fourth
edition addressed 2010 Code edition and 2011 addenda. In this
entirely new publication experts discussed several ongoing issues
even beyond 2015 Code edition. With entirely new and extensively
re-written chapters, the Code Experts had in mind the use of this
publication focused on the Addenda leading to the 2017 B&PV
Code.
This edition is available in a convenient two-volume format
that focuses on all twelve sections of the ASME Code, and has
two additional chapters covering the foreseeable new trends of the
ASME boiler and pressure vessel codes. Several chapters are comprehensively covered for this edition by 51 ASME B&PV Code
experts, whose biographical data is included in the two volumes.
An easy and quick to understand introduction in the front matter
of each of the volumes succinctly explains what is elaborated in
nearly 2000 pages of this 2-volume publication. Another feature
of this publication is all users of Boiler and Pressure Vessel Code
can identify from the index the 8000 individual Code related items.
All of the 51 authors who contributed to 40 Chapters in this fifth
edition considerably updated, revised or added to the content matter covered in the fourth edition to address the current and future
trends as well as dramatic changes in the industry in the ASME
Boiler and Pressure Vessel Code Sections I through XII, and B31
Piping Codes that appear in Volume 2.
Considering significant organizational changes are taking place
in ASME that reflect the Industry’s demands both in USA and
internationally, salient points of these have been captured in both
the volumes by experts who have firsthand information about
these. Volume 1 covers ASME Code Sections I through VII, and
Volume 2 addresses ASME Code Sections VIII through XII. Continuing and replacement authors have considerably updated the
text, tables, and figures of the previous edition to be in line with
the 2015 Code and topics pertinent to 2017 B&PV Code, bringing
the insight knowledge of these experts in updating the previous
edition. Fresh look has been provided by new authors, who in
replacing previous contributors of few chapters, have provided
added perspectives rendered in the earlier editions. In certain cases,
the chapters had been entirely rewritten by replacement experts,
with new titles but addressing the same topics while revising in
its entirety and updating the information to the 2015 ASME Code
Edition and topics pertinent to 2017 B&PV Code.
Volume 1 has Chapter 1 covering “Section I—Introduction to
Power Boilers” which has been authored by two new contributors,
replacing the previous one, who revised this chapter considerably.
Likewise Chapter 2 “Section VII—Recommended Guidelines for
The Care Of Power Boilers” has a replacement author who has
revised the chapter to a considerable extent. Chapter 3 for this edition has been reorganized considering the changes in the application of material properties; accordingly Section 3.6 of Chapter 3
of the fourth edition, “Non-metallic Material used in Structural
Applications”, has been dropped for the fifth edition and a considerably enlarged version of this topic is Chapter 12 for this edition.
Considerable changes in this chapter, including graphics, have
been updated and included in this edition.
In volume 1 Chapters 4 through 7, 9 through 11, 14 and 16 of
the fourth edition, have been updated and revised considerably by
the continuing authors. Chapter 12 of this edition addresses new
code material “Report on Committee on Nonmetallic Pressure
Piping Systems, with its published requirements in three separate
standards: NM-1 Thermoplastic Pressure Piping Systems; NM-2
FRP Pressure Piping Systems; and NM-3 Nonmetallic Materials
(includes specifications and material properties similar to BPV
Code Section II)” by code experts. Chapters 13, 18, 19 and 20 have
new authors replacing the previous contributors and thereby considerably revising fourth edition content of these chapters. Chapter
15 covering Code Section III Division 2 has a replacement author
in addition to others experts to address topics which had not been
covered in the previous editions. Chapter 17 that covers “Division 5—High Temperature Reactors” authored by Code experts
has considerable material from Chapter 12 of the fourth edition,
who authored it in the fourth edition, included in this Chapter 17
of the current fifth edition. Chapter 8 has a replacement author for
this fifth edition.
Volume 2 has chapters addressing Code Sections VIII through
XII with additional code material consistent with the current 2015
Code edition and topics pertinent to 2017 B&PV Code. Chapters
25, 27 and 38 have replacement authors in lieu of the fourth edition
contributors, whereas in Chapter 22 a contributor has dropped out
for this edition. Chapters 21 and 23 have a contributor in addition to continuing authors, whereas Chapter 34 has a replacement
xlvi t Preface
author in addition to the continuing contributor. Chapters 24, 26,
28 through 33, 35 to 37 have continuing authors contributing for
the fifth edition.
In volume 1 Chapter 12 is a new chapter, and in volume 2 only
Chapters 39 and 40 are new chapters which are addressed by code
experts with chapter 39 being a futuristic chapter covering fusion
energy devices and Chapter 40 being a chapter tracing the historical background of code rules for nuclear vessels.
Continuing chapters of the fourth edition are chapters covering B31.9 Building Services and ASME Standards For Piping;
B31T Standard For Toughness Requirements For Piping; B31.5:
Refrigeration Piping and Heat Transfer Components; B31E
Standard for Seismic Design and Current ASME Edition Retrofit
of above Ground Piping Systems; B31J Standard for Test Method
for Determining Stress I- Factors for Metallic Piping Components; B31.4 Standard for Pipeline Transportation Systems for
Liquid Hydrocarbons and Other Liquids; B31.11 Standard for
Slurry Transportation Piping; B31G: Manual for Determining
the Remaining Strength of Corroded Pipelines and B31Q: Qualification of Pipeline Operators; and B31.12: Hydrogen Piping and
Pipelines.
K. R. Rao, Ph.D., P.E.
Editor
Introduction
This fifth edition is in two volumes composed of 11 Parts, with
Parts 1–5 in Volume 1, Parts 6–11 in Volume 2. Common to both
volumes is the front matter, including the Organization of the Code.
Organization and Operation of the ASME Boiler and Pressure Vessel (B&PV) Committee has been initially authored by Martin D.
Bernstein for the first edition, appropriately updated in the second
and third editions by Guido G. Karcher capturing the dramatic
changes in the ASME B&PV organization. The fourth edition was
updated by Joel G. Feldstein and Thomas P. Pastor. The current
fifth edition is updated by Thomas P. Pastor, Ralph Hill III, and
Richard (Rick) Swayne who hold senior leadership positions in the
Boiler and Pressure Vessel Code Committees.
An index is provided at the end of each volume as a quick reference to topics occurring in different Code Sections of that volume.
In addition to indexing several topics covered in this publication,
it is also meant to assist in reviewing the overlaps of the ASME
Boilers & Pressure Vessel Code Sections/Subsections/Paragraphs
occurring in the particular volume. In each chapter, all discussions
generally pertain to the latest 2015 Code Edition unless noted otherwise by the chapter author(s).
The fourth edition was published in 2012 in two volumes and
had a total of 147 contributors for this publication, since the initial
first edition.
The third edition published in 2009 in three volumes was split
into three separate books - the first was the fourth edition of
the “Companion Guide to the ASME Boiler & Pressure Vessel
Code” published in 2012 and the other two books were “Continuing and Changing Priorities of ASME Boiler & Pressure
Vessel Codes and Standards” published in 2014; and “Global
Applications of The ASME Boiler and Pressure Vessel Code”
published in 2016.
Unique for this edition with two volumes which addresses Code
Sections I through XII, in addition to several ASME B31 Piping
Codes is the inclusion of two additional chapters addressed by
ASME Code experts who cover “Section III Div 4: Fusion Energy
Devices” and “History, Philosophy, & Background of Section Ill,
& Development of ASME Code Rules for Nuclear Vessels”.
Each of the 51 contributors covering 40 chapters of the current fifth edition captured ‘up-to-date’ Boiler and Pressure Vessel
Codes and Standards, making this publication once again a comprehensive “Companion Guide Book”.
The ASME Code is generally accepted in the United States (and
in many foreign countries) as recognized minimum safety standard
for the construction of pressure vessels and piping. Toward that
end, these two volumes can be considered “a primer.” Although
this primer is authored by several Code Committee members who
are considered experts in their respective fields, the comments and
interpretations of the rules contained in this publication are strictly
the opinions of the individual authors; they are not to be considered official ASME Code Committee positions.
Volume 1 has five Parts, each addressing a unique aspect of the
Code. Part 1 covers Power Boilers (Code Sections I and VII); Part 2
covers Materials and Specifications (Code Section II). Scope of
Part 2 has been considerably enlarged to address the “sub-topics”
of “material specifications” which are the essence of the B&PV
Codes and Standards. Basis for Acceptance of B&PV Codes for
“International Material Specifications” are also addressed. Considering the importance of current and future nonmetallic construction codes and standards, coverage of Section 3.6 of Chapter 3 of
fourth edition has been included in the discussions of Chapter 12
of this fifth edition.,
Part 3 provides an in-depth commentary on Rules for Construction
of Nuclear Power Plant Components (Code Section III, Division 1).
Previously, “Pumps” and “Valves” were addressed in a single chapter
in the third edition. This edition continues the coverage of fourth edition Chapter 13 dealing with nuclear pumps and Chapter 14 addressing
nuclear valves. In addition, changes in this fifth edition are in Chapters 12 and 17. Chapter 12 discussed Subsection NH in previous
editions. However, because Subsection NH has been incorporated
into Section III, Division 5, the discussion previously presented in
Chapter 12 has been incorporated in Chapter 17. On the other hand
Chapter 12, in this edition is based on a Report on Committee on
Nonmetallic Pressure Piping Systems detailing NM-1 Thermoplastic Pressure Piping Systems; NM-2 FRP Pressure Piping Systems
and NM-3 Nonmetallic Materials which includes specifications
and material properties similar to BPV Code Section II.
As in the previous editions, Section III Division 2 continues to be
included in Part 3, addressed by several additional contributors with
expertise in their respective areas. Section III Divisions 3 and 5 are
included in Part 3, with Division 5 addressing the “Generation IV
Nuclear Reactors”, which is an add-on-aspect of this edition.
Part 4 covers Sections IV and VI of B&PV Code. Part 5 covering Nondestructive Examination (NDE), Code Section V of B&PV
Code is now included in Volume 1.
Volume 2 covers Parts 6–11, with Part 6 covering Section VIII–
Rules for Construction of Pressure Vessels. In Part 6, experts
dealing with Divisions 1, 2, and 3 provide in-depth criteria and
commentary of Code Section VIII with the latest of the code stipulations. In addition there is a chapter by an expert of the B&PV
Code who discusses safety and litigation issues.
Part 7 addresses welding and brazing qualifications of Code
Section IX by the contributor with expertise at the helm of Code
Committee deliberations.
Part 8 covering Code Section X pertains to fiber-reinforced plastic pressure vessels has been considerably revised by the current
contributor for this edition.
Part 9 providing in-depth discussions of Code Section XI in
Chapters 27 through 34 is updated by authors associated with the
specific subgroups and subcommittees dealing with the topics
addressed in the previous editions. A chapter from the third volume
xlviii t Introduction
of the third edition dealing with Applications of Elastic-Plastic
Fracture Mechanics is included in this volume.
Part 10 covering Code Section XII dealing with Transport Tank
Code which was in the third volume of the third edition is now
included in this part.
Part 11 updates the coverage of ASME B31 Codes and Standards in Chapters 35 through 38. Chapter 35 has Code for B31.1
Power Piping and Chapter 36 updates B31.3 Process Piping and
B31.5, B31E, B31J and B31T. Chapter 37 updates the coverage of
fourth edition topics B31, B31.8, B31.11 and B31Q; and Chapter
38 updates B31.12.
Two additional chapters are covered in a new Part 12 of this
fifth edition which provides in two separate and consecutive chapters ‘futuristic’ and ‘historical’ aspects of ASME B&PV Codes
and Standards. Chapter 39 provides the futuristic aspect – a new
“Section III Div 4: Fusion Energy Devices” and in chapter 40 the
“history and philosophy of Section III” are discussed.
VOLUME 1
Chapter 1 of the 1st edition was authored by the late Martin
D. Bernstein. It discussed Power Boilers, Section I of the ASME
Boiler and Pressure Vessel Code. His objective was to provide an
overview of the intent, application and enforcement of Section I
rules for the construction of power boilers. This chapter was an
abbreviated version of the book Power Boilers, A Guide to Section I of the ASME Boiler and Pressure Vessel Code, which was
used as the textbook for a two day ASME professional development course on Section I developed and taught for many years by
Martin D. Bernstein and Lloyd W. Yoder. Mr. Yoder reviewed and
updated Chapter 1 for the 2nd edition to commemorate his close
friend and associate. In doing so, he found that only minor changes
and updating were required because the 1st edition Chapter 1 was
so well crafted by Mr. Bernstein, like all of the many things he was
known to have written.
Chapter 1 was reviewed and updated for the third edition by
John R. MacKay, long-time member and past chairman of Standards Committee I (BPVI), formerly Subcommittee I. Mr. MacKay
also reviewed and updated the chapter for the fourth edition to
cover revisions to Section I, Power Boilers through the 2010 Edition, 2011 Addenda. Significant additions were included that pertain to the addition of PG-26 Weld Strength Reduction Factor and
changes to PG-58 Boiler External Piping and Boiler Proper Connections and PG-105 Certification Marks.
Chapter 1 has been updated for the fifth edition by Ed Ortman
and Jay Vattappilly, both current members of BPV I as well as
some of its various subgroups. This edition brings Chapter 1 up
to the 2015 Edition of Section I and also includes a paragraph
on items the Committee is working on for the 2017 Edition and
beyond. A couple of major updates are new riveting rules published in Part PR in the 2013 Edition of Section I and new rules
for locomotive boiler published as a new Part PL in the 2015
Edition.
Chapter 1 covers some of the more important aspects of Section
I construction, including the history and philosophy of Section I:
how the ASME Code works; the organization and scope of Section
I; the distinction between boiler proper piping and boiler external
piping; how and where Section I is enforced; and the fundamentals of Section I construction. These fundamentals include permitted materials; design; fabrication; welding and postweld heat
treatment; NDE; hydrostatic testing; third-party inspection; and
certification by stamping and the use of data reports. A number of
design examples have also been included in this chapter.
The design and construction of power boiler involves the use
of other sections of the ASME Code besides Section I, such as
Section II, Materials; Section V, Nondestructive Examination;
and Section IX, Welding and Brazing Qualifications. In a rather
unusual arrangement, the construction rules for boiler piping are
found partly in Section I and partly in the B31.1 Power Piping
Code. This arrangement has led to considerable misunderstanding
and confusion, as explained in Chapter 1, Section 1.5, where the
distinction between boiler proper piping and boiler external piping
is discussed.
In the 1st edition Mr. Bernstein stated “The ASME B&PV Code
changes very slowly but continuously. Thus, although this chapter
provides a substantial body of information and explanation of the
rules as they now exist, it can never provide the last word. Nevertheless, the chapter should provide the User with a very useful
introduction and guide to Section I and its application.” His words
are still true for the reason that Chapter 1, as updated, retains the
philosophy and intent of the original author, Martin D. Bernstein.
Chapter 2, authored by William L. Lowry in the current update,
covers ASME Boiler & Pressure Vessel Code Section VII, Recommended Guidelines for the Care of Power Boilers. This Section
was reorganized since the 4th Edition of the Guide, by Mr. Lowry
with input from 10 current and past members of Code Committees and reviewed by 29 Peer reviewers prior to a review, edits
and approval by Section I, Power Boilers Committee. The primary
discussion is about industrial, gas or oil fired, watertube boilers,
which constitute the vast majority of Power Boilers constructed.
Other boiler types are discussed in separate Subsections of Section
VII. No information was discarded from the previous Edition of
Section VII. The purpose of Section VII is stated in the Introduction of Section VII, “The purpose is to promote safety in the use
of power boilers. These guidelines are intended for use by those
directly responsible for operating, maintaining, and examining
power boilers.”
The subject of Subsection 1 is Watertube Drum-Type Industrial
Steam Boilers. The Articles that follow deal with Fundamentals
such as Steam Generation, Combustion, and Boiler Efficiency;
Boiler Operation; Boiler Auxiliaries; Appurtenances; Instrumentation, Controls, and Interlocks; Examination; Repairs, Alterations,
and Maintenance. Subsection 2 subjects pertain to all steam boilers.
The Articles address Protecting Heat Transfer Surfaces; Preventing Boiler Failures; Documents, Records and References. Subsection 3 covers Other Boiler Types. All information regarding other
boiler types from previous Editions of Section VII is contained
along with several additions. Article 301 Electric Steam Boilers
is completely new and a ‘must read’ prior to purchasing one of
the several designs available. Subsection 4 includes all information specifically addressing Coal-Fired and Other Solid-Fuel-Fired
Boilers.
Subsection 5 is a single Glossary combined from the three
separate Glossaries of prior Editions and coordinated with the
latest edition of American Boiler Manufacturers Association’s
‘Lexicon’. Checklists for Maintenance Examinations are contained
in Appendix A.
It is suggested that the reader also review existing literature, such
as manufacturer’s instructions or existing company procedures,
for additional details. Section VII is a Nonmandatory Standard,
and it provides recommended practices and serves as a guideline.
However, Section VII touches on many activities that the Owner–
Operator personnel must be aware of before a power boiler is
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t xlix
commissioned. New personnel who are not familiar with boiler
operation, maintenance, and examination can use Section VII as
an introduction to these activities. Experienced personnel will find
Section VII to be a good review of the essentials of operation,
maintenance, and examination, with useful figures and references.
Chapter 2 of this Guide also contains some insights and information from previous Editions of the Guide that are not currently
contained in Section VII.
Chapter 3 has multiple authors, and in Chapter 3.1, History of
Materials in the ASME Boiler and Pressure Vessel Code, Domenic
Canonico traces the chronological evolution of materials and associated technologies, from the need for materials to accommodate
riveted construction to the acceptance of fusion welding as a fabrication process. Included in this discussion are the application of
advanced materials, the revisions to the basis for setting allowable
stress values, and the acceptance of Material Specifications other
than those approved by ASTM. Also covered is the evolution of
materials, from their humble beginning as a 35-page inclusion in
the 1914 Edition of the Boiler Code to the 3994-page, four-Part
2001 Edition of Section II of the ASME B&PV Code. Chapter 3.1
provides some insight not only into the materials needed for the
design and fabrication of power boilers but also into the determination of the Maximum Allowable Working Pressure. With the
aid of tables, Domenic discusses the Material Specifications from
the 1914 through the present Code Editions. Chapter 3.2, authored
by John Grubb in the current update, discusses Code Section II,
Part A—Ferrous Material Specifications, adopted by ASME for
the construction of boiler, pressure vessel, and nuclear power plant
components. He notes that all materials accepted by the various
Code Sections and used for construction within the scope of the
Code Sections’ rules must be furnished in accordance with the
Material Specifications contained in Section II, Parts A, B, or C, or
referenced in Appendix II of Part A—except where otherwise provided in the ASME Code Cases or in the applicable Code Section.
Discussions in Chapter 3.2 include The Organization of Section II,
Part A, Guideline on the Approval of New Materials, Appendices,
and Interpretations.
In Chapter 3.3, Richard C. Sutherlin provides the basis of a commentary on Section II, Part B – Nonferrous Material Specifications,
adopted by ASME for the construction of boiler, pressure vessel
and nuclear power plant components. He notes that all materials
allowed by the various Code Sections and used for construction
within the scope of the Code Sections’ rules must be furnished in
accordance with the Material Specifications contained in Section
II, Part B or referenced in Appendix II of Part B, except where
otherwise provided in the ASME Code Cases or in the applicable
Code Section. Richard discusses Alloy Definitions; Organization
of Section II, Part B; Material Specifications included in Section II,
Part B: Guidelines for Approval and Use of Materials for ASME
Code Construction; Submittal of Technical Inquiries to the Boiler
and Pressure Vessel committee; Acceptable ASTM and non-ASTM
Editions; Guidelines on Multiple Marking of Materials; Appendices; ASME Code Cases; Interpretations; and the use of Nonferrous
Material Specification in the Piping Codes 31.1 and 31.3. Richard
also provides cross references to weldability; the ASME Code Section I, III, IV, VIII and IX; and Piping Codes B31.1 and B31.3.
Chapter 3.4, authored by Marvin Carpenter and William Newell,
discusses Section II, Part C—Specification for Welding Rods, Electrodes, and Filler Metals. Welding plays a major role in the fabrication of pressure vessels and related components to the requirements
of the ASME B&PV Code. Marvin provides the basis for the Specifications and Standards enveloped by Section II, Part C and their
relations to the ANSI/AWS specifications. Section II, Part C does
not include all the welding and brazing materials available to the
industry—only those Specifications applicable to ASME Code
Construction. Discussions also include Code Cases pertinent to
this chapter. Chapter 3.4 highlights the major features of the Welding Material Specifications contained in Section II, Part C and the
relationship of these Specifications to other Sections of the Code,
including Section IX. Included are the electrode classification system, material descriptions, welding material applications, welding
material procurement, and filler-metal certification. Chapter 3.4
should prove useful for one to gain a basic understanding of ASME/
AWS Welding Material Classification and Specification.
Chapter 3.5 has been revised by John Grubb and Jeff Henry who
reviewed important aspects of Section II, Part D – Properties. The
discussion includes the properties of ferrous and nonferrous alloys
used in the design of components for the B&PV and Nuclear Construction Codes. Explanations are provided for the use of tables
within Section II, Part D, including the tables of maximum allowable stresses and design stress intensity values for the alloys adopted
by the Construction Codes, as well as the tables of yield strength
and ultimate tensile strength values at a range of temperatures. The
discussion also addresses the use of the external pressure charts
as well as the values collected in the Physical Properties tables
that are required for Code design. Explanations are provided for
how the allowable stresses for the different Construction Codes are
developed and the data requirements for new materials briefly are
reviewed. The chapter is a useful overview to understanding how
the compendium of information on relevant material properties
that is collected in Section II, Part D can be successfully exploited
by Code users.
Chapter 3.6, authored by Anne Chaudouet and Elmar Upitis,
discusses Section II, Part A and Part B—International Material
Specifications adopted by ASME for the construction of boiler,
pressure vessel, and nuclear power plant components. Most ASME
material specifications are based on ASTM specifications. ASME
Section II also includes rules for acceptance of material specifications of recognized National or International organizations other
than ASTM. ASME does not have permission to publish such
specifications. Section II includes cover sheets giving the additional ASME requirements for specifications which ASME has
adopted for ASME Code construction. Chapter 3.6 also discusses
the process of adoption of the CEN specifications in Europe with
consequences on the corresponding ASME specifications. The EN
material specifications are restricted to European specifications
themselves with no national endorsement, foreword and annexes
and dated as the year of approval by CEN.
Chapter 3.6 describes the following international specifications
that are adopted by ASME and included in Section II: Australian
Standard basis of SA/AS 1548 Specification for Steel Plates for
Pressure Equipment; Canadian Standard basis of SA/CSA-G40.21
Structural quality steel; European Standards bases of SA/EN
10025 Hot rolled products of structural Steels—Part 2 Non-alloy
structural steels, of SA/EN 10028 Flat products made of steels for
pressure purposes—Part 2 Non-alloy and alloy steels with specified elevated temperature properties, Part 3 Weldable fine grain
steels, normalized, Part 4 Nickel alloy steel with specified low
temperature properties and Part 7 Stainless steels, SA/EN 10088
Stainless Steels—Part 2 Sheet/plate and strip for corrosion resisting steels for general purposes, SA/EN 10216 Seamless steel tubes
for pressure purposes—Part 2 Non-alloy and alloy steel tubes with
specified elevated temperature properties, SA/EN 10217 Welded
steel tubes for pressure purposes—Part 1 Non-alloy steel tubes with
l t Introduction
specified room temperature properties, and of SB/EN 1706 Aluminum and Aluminum Alloys—Castings—Chemical Composition
and Mechanical Properties; Chinese Standard basis of SA/GB 713
Steel Plates for Boilers and Pressure vessels; Indian Standard basis
of SA/IS 2062 Steel for General Structural Purposes, Japanese
Standards bases of SA/JIS G3118 Carbon steel plates for pressure
vessels for intermediate and moderate temperature services, SA/
JIS G4303 Stainless steel bars and of SA/JIS G5504 Heavy-walled
ferritic spheroidal graphite iron castings for low temperature service, and French standard basis of SA/NF A 36-215 Weldable
fine grain steels for transportation of dangerous substances. Some
grades of international material specifications are approved for
Code construction by use of Code Cases. Chapter 3.6 also includes
a brief discussion of these materials.
In Chapter 4, Roger Reedy provides commentary for understanding the principles of the ASME B&PV Code. Roger traces
the history of the Code, from its initial publication in 1914 to the
present. He also identifies the role of the volunteers who write the
Code and the process used to establish Code with the outstanding
safety record that has been achieved by the current consensus process. Roger suggests that Code Users apply common sense when
using and interpreting the Code He emphasizes that “the Code is
not a handbook and cannot substitute for the use of engineering
judgment.” Also, Roger emphasizes the need for a better understanding of the basic principles of the Code. It is necessary to
understand the application of design factors for each Section
ASME Boiler and Pressure Vessel Code, recognizing there are a
number of different design factors and stress theories in the different Code Sections and Divisions. Roger states that the term “safety
factor” is both incorrect and misleading, because a reduction in
the factor seems to indicate a reduction in safety. In fact, when the
Code Committee considers a reduction in design factor, it allows
the reduction only after it determines that other changes in Code
requirements have compensated for the resulting increase in allowable stress values. There have been very significant reductions in
design factors in the past few years, and more will come in the near
future.
Reedy points out concerns with the use of Finite Element Analysis when it is used in design activities. He emphasizes that the
ASME Code of Ethics must be followed when designing pressurized equipment. Other issues addressed are evaluation of new
hypothetical loads on equipment that has been Code Stamped, and
the purpose of the hydrostatic test of pressurized equipment.
Chapter 5, authored by Richard W. Swayne, describes the general
requirements of Section III applicable to all Construction Classes,
including concrete structures and steel vessels, piping, pumps, and
valves. It identifies how to classify components and describes how
the jurisdictional boundaries of Section III define what is within
and what is outside the scope of the Code. This chapter includes
coverage of Subsection NCA, which pertains to general requirements for Divisions 1, 2, and 3 of Section III. Division 1 includes
steel items such as vessels, storage tanks, piping systems, pumps,
valves, supports, and core support structures for use at commercial
nuclear power plants; Division 2 includes concrete reactor vessels
and concrete containment vessels; and Division 3 includes requirements for the construction of containment vessels for transportation
of spent nuclear fuel. The scope of Division 3 now also includes
requirements for construction of storage canisters and transportation containments for spent nuclear fuel.
Chapter 5 also explains the use of Code Editions, Addenda, and
Code Cases. The requirements for design basis, design and construction specifications, and design reports are described, and the
responsibilities and quality assurance program requirements of the
different entities involved in nuclear power plant construction—
from the Material Organization to the Owner—are addressed.
Requirements for ASME accreditation, application of the ASME
Code Symbol Stamp, and use of Code Data Reports are described.
With in-depth information, Mr. Swayne outlines the basis for
exemptions, component classification, load combinations, responsibilities, Certificate of Authorization Holders and Quality System
Certificate Holders. Also, Mr. Swayne provides cross-referencing
to other Code Sections and Subsections, such as Sections III and
XI, as well as to pertinent Regulatory Guides, such as the U.S.
Code of Federal Regulations (CFR).
Chapter 6 has been updated by Chakrapani Basavaraju and David
Jones to address changes in 2013 and 2015 versions of the Code. The
major highlights include expression for flexibility factor, and more
accurate expressions for C2 and K2 indices for reducers, C3’ and C3
indices for straight pipe, updated piping seismic criteria in NB-3200,
and PWHT exemptions for certain P number material weld joints. It
should be noted that 2010 version of the Code includes discussions
Code Cases N-761 and N-792 pertaining to the evaluation of fatigue
effects of components exposed to LWR environments, and discussion on changes to the rules on temper bead welding.
Authors cover Subsection NB, Class 1 Components. In presenting the rules and requirements for Section III, Subsection NB, the
authors discuss the theories, on which the rules and requirements
are based, the appropriate application for applying the rules and
requirements, and the interfaces for design, analysis, and construction. The chapter emphasizes the analytical rules and requirements,
and makes reference to the Criteria of the ASME Boiler and Pressure Vessel Code for Design by Analysis in Sections III and VIII,
Division 2, 1968 that is considered the basis document for Sections
III and VIII. John provided the design theory and ramifications of
the key considerations, with cross-references to other Code Sections
discussing the subtle differences between the Section III design criteria and the Section I and Section VIII, Division 1 design criteria.
In addition, commentary is provided on the Code requirements of Class 1 for design by analysis “because of the prominent role played by stress analysis in designing vessels by the
rules of Section III . . . and because of the necessity to integrate
the design and analysis efforts.”—The authors emphasize against
the design by analysis theme of NB is to provide high assurance
that the failure modes of burst, plastic collapse, excessive plastic
deformation, fatigue, ratcheting, brittle fracture, elastic instability
(buckling), stress corrosion, and corrosion fatigue. The intent of
the rules of NB is to provide assurance that high quality is reached;
therefore, stress analysis is added to the “NB rules for all of the
disciplines and their interaction” in an effort to reach high quality.
Chapter 6 has been updated by Greg Hollinger and David Jones to
the 2007 version of the Code including discussions of the differences between Section VIII Division 2 and Section III NB. Discussions have been added on the Section VIII Division 2 rules dealing
with Limit Analysis, Finite Element Analysis and Environmental
Fatigue, and new methods for fatigue of weldments.
Chapter 7 has been updated by Chakrapani Basavaraju to
address changes in 2013 and 2015 versions of the Code. The
major highlights include standard design rules for classes 2 and
3 valve ends of socket welded type, and non-welded type used in
instrument, control, and sampling line of nominal pipe size (NPS)
1 (DN 25) and smaller, revised Tables NC/ND-3673.2(b)-1 to
provide stress intensification factors for branch connections with
branch to run mean radii ratio (r/R) £ 0.5, and PWHT exemptions
for certain P number material weld joints. It should be noted that
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t li
2010 version of the Code includes new seismic rules for piping
design, and alternate rules for axial compressive membrane stress
in the design of cylindrical storage tanks. This addresses pressure
atmospheric tanks, and 0–15 psig tanks as presented in the ASME
B&PV Code, Section III, Division 1, Subsection NC, Class 2 Components and Subsection ND, Class 3 Components. This chapter
does not address piping, pumps, and valves; these are addressed
in Chapter 8 for Class 2 and Class 3 Piping, and in Chapter 13 for
Nuclear Pumps and Valves. This chapter discusses, in order, each
of the eight major Code Articles: Introduction; Materials; Design,
Fabrication and Installation; Examination; Testing; Overpressure
Protection and Name Plates; and Stamping and Reports. In the
1971 Edition, Subsection NB was fully developed in the evolution
of the Nuclear Codes; all other were written by using the outline
established for NB. Consequently, many of the basic paragraphs
contained in Subsection NB and other reference documents were
included verbatim in both Subsections NC and ND, when the subsections were published as separate volumes in the 1974 Edition.
Subsections NC and ND are a combination of rules and requirements taken from Section III, Subsection NB and Section VIII. In
Chapter 7, Thomas has referenced all of these Codes and meticulously identified both obvious and subtle differences between Subsection NB, the parent Code, and Subsections NC and ND. Thus,
because Thomas addresses the Articles of Subsections NC and ND
in this part of the commentary, he presents comparisons, the most
probable source of origin of the Code requirements, certain insights
as well as contradictions that seem to exist, and the specific source
document and some of the underlying theory. He provides crossreferences to other Code Sections/Subsections/Paragraphs where
applicable. Marcus has taken this work and simplified it where
possible, and updated it to the 2007 Edition.
Chapter 8, was authored by Don Landers for the first through
third Editions, Jack Cole updated the chapter for the fourth edition,
and now Mark Gray has worked with Jack to complete the update
for the fifth Edition. This update covers the changes in place and
underway for the 2015 Edition of Section III, Division 1 (Piping).
Chapter 7 indicates that the requirements of Section III, Division 1
provide for three classes of components. Chapter 8 indicates that
each Class can be considered a quality level, with Class 1 the highest and Class 3 the lowest. These quality levels exist because of the
various requirements for each Class in Section III related to materials, fabrication, installation, examination and design. Design was
placed last on the list because sufficient evidence exists to indicate
that the other considerations listed are more important than the
design requirements in constructing an acceptable piping system.
In Chapter 8, Don, Jack, and now Mark develop the above list of
considerations in the commentary regarding the criteria and basis
for requirements of the Subsections NB, NC, and ND for Piping.
They provide the stress requirements for Nuclear Classes 1, 2,
and 3 piping and the corresponding design processes and Design
Specifications, with pertinent references, tables, and figures. Their
commentary provides insight into load classifications and the
responsibility of Owners. The Code rules ensure that violation of
the pressure boundary will not occur if the Design Specification
satisfactorily addresses all issues necessary for Code compliance.
In the commentary, Donald, Jack, and Mark show the subtle differences between the piping rules and design by analysis, and they
explain what items the analyst should be concerned with in satisfying Code requirements. They provide cross-references to B31.7
Code techniques and discuss the recent regulatory acceptance of the
seismic design requirements for piping in Section III, Division 1.
In the fifth edition, Jack and Mark have provided updates that
discuss recent Code changes to piping rules that include the adoption of Code Cases for evaluation of reactor coolant environmental fatigue evaluation, update of the Code Case for construction of
Class 3 HDPE pipe, alternate rules for simplified elastic plastic
analysis using Ke, and upcoming changes for buried Class 2 and 3
pipe design rules.
Chapter 9, has been authored by Kamran Mokhtarian for the first
two editions and updated for the 3rd edition by Roger F. Reedy
who continues the discussion of Subsection NE, Class MC Components. This chapter summarizes some of the more significant
requirements of Section III, Subsection NE and provides a commentary on such requirements. Kamran’s comments and interpretations of the rules are based on his several years of experience in
design, analysis, and construction of containment vessels, as well
as his participation in various ASME Code Committees. Some
comparisons of the rules of Section VIII are included for information. The analysis procedures are not dealt with in any great detail,
for they are similar to those of Subsection NB and the old Section
VIII, Division 2. However, more emphasis is placed on the unique
features of Subsection NE. Further, the stress analysis procedures
do not in any way compare with the stress analysis procedures in
the current Section VIII, Division 2 Code for pressure vessels.
A number of Code Cases and references regarding the rules of Subsection NE are cited, with cross-references to other Code Sections
and Subsections. This chapter is based on the 2010 Edition of the
Section III Code. The items covered in Chapter 9 include Scope
of Subsection NE; Boundaries of Jurisdiction of Subsection NE;
General Material Requirements; Certified Material Test Reports;
Material Toughness Requirements; General Design Requirements;
Qualifications of Professional Engineers; Owner’s Design Specifications; Certified Design Report; Design by Analysis; Appendix F;
Fatigue Analysis; Buckling; Reinforcement of Cone-to-Cylinder
Junctions; Plastic Analysis; Design by Formula; Openings; Bolted
Flange Connections; Welded Connections; General Fabrication
Requirements; Tolerances; Requirements for Weld Joints; Welding Qualifications; Rules for Making, Examining, and Repairing
Welds; Heat Treatment; Examination; Qualification and Certification of NDE Personnel; Testing; Overpressure Protection; and
Nameplates, Stamping, and Reports.
Because of the new nuclear power plants soon to be constructed,
the rules of Subsection NE should be modified to address the needs
of the industry for the new plants. There are many changes that can
be made without sacrificing safety. The chapter has been updated
to identify all significant changes to the Subsection NE Code from
2007 to 2015.
Chapter 10 was authored for the first edition by Robert J. Masterson,
who covered Subsection NF (Supports). The second, third and fourth
editions had been updated by Uma S. Bandyopadhyay with the current
third edition addressing the changes of the 2010 Code Edition. Robert
traced the historical background of this Subsection, which provides
a single source of rules for the design, construction, fabrication, and
examination of supports for the nuclear industry. Section III, Division
1, Sub-section NF was developed to provide rules for the estimated
10,000 piping and component supports existing in a typical nuclear
power plant. The criteria and commentary of Chapter 10 provides
information on the origin and evolution of design rules and is intended
to allow designers, engineers, and fabricators to make better use of
Subsection NF. Topics of greatest interest are discussed from both a
technical and a historical viewpoint. However, it is not the intent to
address every detail associated with the use of Subsection NF.
Subsection NF rules have evolved dramatically over the past
30 years so that today’s support rules seldom resemble the original
lii t Introduction
rules of 1973. In Chapter 10, commentary is provided to explain
how the criteria are used, the source and technical basis for equations and rationale, and the reasons for change. Robert covers the
scope and classification of the types of supports and attachments.
Subsection NF contains rules for the material, design, fabrication,
examination, testing, and stamping of supports for Classes 1, 2, 3,
and MC construction. Robert provides cross-referencing to Subsections NB, NC, ND, NE, and NG, as well as to the B31.1 and
B31.3 Codes, and he also addresses Code Cases and Interpretations. Discussions include Subsection NF Appendices and with
the help of figures, tables, and references, it is anticipated that the
reader will develop a better understanding of Subsection NF and
appreciate its complexities and usefulness.
Chapter 11, authored by Richard O. Vollmer, deals with Subsection NG (Core-Support Structures). This chapter provides commentary and practical examples on the materials, design, fabrication,
installation, and examination requirements for core-support structures in Section III, Division 1, Subsection NG. In addition, commentary on Section XI as it applies to core-support structure repair,
replacement, examination, and inspection requirements is presented.
The objective of the Subsection NG rules is to provide a Code for the
design and manufacture of structures that support the core in pressurized water reactors (PWRs) and boiling water reactors (BWRs).
These rules are similar to the Subsection NB rules, though there
are important differences due to differences in basic requirements
between pressure boundary and reactor internals structures. With the
aid of figures, tables, and examples, important considerations in the
design of core-support structures, the Owner’s Design Specification,
and the jurisdictional boundaries between core-support structures
and reactor pressure vessels (RPVs) are discussed. The differences between core-support structures, internal structures, threaded
structural fasteners, and temporary attachments are explained. Discussions also include unique conditions of service; construction
materials; special materials; fabrication and installation rules; examination and repair; general design rules; design by analysis; testing
and overpressure protection; and examples of load combinations for
core-support structures.
The first edition was written based on the 1998 Edition ASME
B&PV Code. In the second edition, the 2001 Edition of the Code
up to and including July 2003 Addenda was used for examples and
discussion points. The third edition was updated to the 2007 Edition
of the Code, with new or additional commentary covering: Background on Subsection NG Development; Discussion of Typical
Materials Used in CSS, IS, and TSFs; Owner’s Design Specification, and Design Reports; Environmental Effects; CSS Code Cases;
Improvements in Subsection NG; Material Degradation Issues;
Compatibility of Subsection NG with Other International Codes;
Trends Towards Realistic Design Loads in Reactor Internals; and
a summary of changes to the Code through the 2007 Edition. The
fourth edition has been updated to the 2010 Edition of the Code with
2011 Addenda, and expanded to provide additional discussion on
stress classification, special stress limits, Code Cases and Interpretations, and potential additions and improvements to the NG rules. The
fifth edition has been updated to reflect the 2015 Edition of the Code
as well as to address new or revised Code Cases and Interpretations.
Chapter 12 discussed Subsection NH in previous editions. However, because Subsection NH has been incorporated into Section
III, Division 5, the discussion previously presented in Chapter 12
has been incorporated in Chapter 17.
Chapter 12, authored by Wes Rowley and Tom Musto, discusses the current and future nonmetallic construction codes and
standards using nonmetallic plastic polymers. The two major
documents already published for many years are the ASME BPV
Code, Section X, Fiber Reinforced Plastic Pressure Vessels and
ASME RTP-1 Standard, Reinforced Thermoset Plastic CorrosionResistant Equipment. Three more related documents will be published in early 2018: NM-1 Thermoplastic Piping Systems, NM-2
Glass Fiber Reinforced Thermoset Plastic Piping Systems, and
NM-3 Nonmetallic Materials.
ASME BPV Code Section X addresses glass/carbon/aramid reinforcing fibers and epoxy/polyester/vinyl ester/phenolic/furan polymer materials. ASME RTP-1 Standard addresses glass reinforcing
fiber and vinyl ester polymer materials. Initially ASME NM-2 and
NM-3 only address glass reinforcing fibers and polyester/vinyl
ester polymer materials.
ASME BPV Code Section X addresses design requirements
for nominal pressures of 150-psig to 3000-psig and nominal temperatures for –65°F to +250°F. ASME RTP-1 Standard addresses
requirements up to 15-psi pressure (typical tank limit) and 180°F
temperature. ASME NM-1 Standard addresses design requirements
with the following statements:
t “The service temperatures and pressures for such applications
are limited by the properties of the specific pipe material
selected for the given application.”
t “The temperatures limits for each thermoplastic material shall
contain a maximum continuous-operating temperature and
pressure and a maximum short-term operating temperature
and pressure for a given time.”
ASME NM-2 Standard addresses requirements of pressures
between 15-psig to 250-psig. ASME NM-3 addresses material
specifications and material properties for both thermoplastic and
thermoset plastic with glass reinforcing fibers. Currently the various B31 piping codes have requirements for nonmetallic piping
(not necessarily consistent across the various applications), but
the long-term plan is for those various B31 piping codes to adopt
the NM-1 and NM-2 Standards for pressure piping systems. The
NM-1 and NM-2 Standards reference NM-3 Standard for applicable material specifications and material physical and engineering
property data.
Chapter 13 was authored for the first edition by the late Douglas
B. Nickerson. The current edition has been revised by Ross R. Klein
of Curtiss-Wright Corporation in Cheswick, PA. This chapter discusses those items that are the driving and controlling forces in
hydraulic systems for nuclear power plants. The pump in each system drives the flow through the piping to provide the transfer of
energy from one component to another. The fluid systems have
varying degrees of criticality, depending on their function. This
chapter explains the relevancy of the ASME Code requirements for
safety-related nuclear pumps using the latest edition of the Code.
Since the Code is limited to pressure-boundary requirements, most
of the conditions necessary for the satisfactory design of a nuclear
pump are not subjected to Code rules. The Design Specification
defines the operational requirements of the pump and is the most
important element in the function and approval. This chapter not
only defines the applicable Code, but it also explains how these
components function in their applications.
The chapter provides a historical perspective for the Code
rules, cross-referencing other Subsections of the Code. The Owners Responsibilities for the system design plays an important
part in establishing the rules applicable to the Design Specification for each safety-related pump. The authors have drawn upon
considerable practical experience in their discussion on operational
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t liii
and qualification requirements for the procurement of these pumps
from the Manufacturer. Non-mandatory Appendix U divides pump
internal parts into various categories and sets up requirements
for appropriate quality levels. Currently the Working Group for
Pumps of Section III is in the process of proposing a revision to
Appendix U in order to make it more useful.
The 5th Edition organization has been retained with the pumps
now covered under Chapter 13 and valves under Chapter 14. Guy
A. Jolly volunteered to update Chapter 14 specific to valves for
the 4th and 5th Editions. Much of the commentary in Chapter 14
has been retained from the Nickerson and Bressler input related to
valves from the Chapter 13, 3rd Edition. Nickerson discusses those
items that are the driving and controlling forces in hydraulic systems for nuclear power plants. The valves control the flow through
these fluid systems and thus the operation of the systems. Fluid systems have varying degrees of criticality, depending on their function. This commentary explains the relevancy of the ASME Code
requirements for safety-related nuclear valves using the latest issue
of the Code. The Code is limited to pressure-boundary requirements. Douglas states that because of this limitation of the scope of
the Code, most conditions necessary to the satisfactory design of a
nuclear valve are not subjected to Code rules. The Design Specification specifies operational requirements and thus is the most important element in their function and approval. This commentary not
only defines the applicable Code but also explains how these components function in their applications. Chapter 14 also discusses the
role of system design and component design engineers, as well as
the integrity of the Manufacturer. Nickerson provides a historical
perspective for the Code rules, cross-referencing other Subsections
of the Code. He notes that Owner’s Responsibilities for system
design plays an important part in establishing the rules applicable
to the Design Specification for each safety-related valve. Drawing
upon considerable practical experience, Nickerson covers operational and qualification requirements for the procurement of these
items from the Manufacturer. He discusses these items for different service conditions with the aid of schematics and references.
Marcus Bressler, a member of the subgroup on Design since 1974,
and Chairman of the working group on Valves from 1974 to 1977,
provides the background to the development of the design rules for
valves, and updates the Chapter to the 2007 Edition of the Code.
Jolly provides details of the ASME B16.34 historical development
and provides the current reference dimensional standards from the
2013 and 2015 Code for use in the construction of “N” stamped
valves based on the Code’s B16.34 reference. He also provides
a list of widely used Valve Standards referenced in ASME B31
piping codes. Valves constructed under the scope of these standards normally are required to meet the wall thickness and pressure temperature requirements of ASME B16.34 but include other
requirements (stem and seat size, stem retention structures, packing chamber details, etc.), which have produced valves that have
a successful operational history in the chemical, petroleum and
power industries. Imposing the design rules of a selected standard
from this group on the non-pressure retaining nuclear valve items
could go far in validated the nuclear valve successful functioning
in service. These standards could be used as reference for the writing of a valve Design Specification and construction of an “N”
stamped valve. Jolly has increased the coverage on pressure-relief
valves to include detailed activity underway at Section III to clarify
requirements related to pilot operated and power actuated pressure
relief valves. He has also included details relating to QME-1 relating to qualification testing required for active valves for functional
adequacy for nuclear power plant service.
Chapter 15 describes the bases and provisions of the Code for
Concrete Containments updating to 2015 Code Edition. The Chapter describes the concrete containment general environment, types
of existing containments, future containment configurations, and
background development including the regulatory bases of concrete containment construction code requirements. The description
covers sequentially the following topics: Introduction, Concrete
Reactor Containments, Types of Containment Systems, Future
Containment Development, Concrete Containments of Future
Reactors, Background Development of Concrete Containment
Construction Code Requirements, Reinforced Concrete Containment Behavior, Concrete Reactor Containment Design Analysis
and Related Testing, Code Design Loads, Allowable Behavior Criteria, Analytical Models and Design Procedures, Special Design
Features, Current Organization of the Code, Fabrication and Construction, Construction Testing and Examination, Containment
Structural Integrity Testing, Containment Overpressure Protection,
Nameplates, Stamping and Reports, Practical Nuclear Power Plant
Containment Designed to Resist Large Commercial Aircraft Crash
and Postulated Reactor Core Melt, Items that should be considered
in Future Revision of the Code, Summary and References.
The basic format of this chapter is kept the same as in the previous edition. The initial edition of this chapter was developed by
John D. Stevenson. For this latest Edition, the updates and additional information relating to the regulatory bases for the code
requirements, future containment designs and considerations for
future revisions of the Code are based upon contributions from
Arthur C. Eberhardt, Christopher A. Jones, Ola Jovall and Clayton
T. Smith.
In Chapter 16, authored by D. Keith Morton and D. Wayne
Lewis, a commentary is provided regarding the containments used
for the transportation and storage packaging of spent fuel and highlevel radioactive material and waste.
In 1997, ASME issued the initial version Division 3 of Section
III. Before the publication of Division 3, Section III, the Section
applicable to the construction of nuclear pressure-retaining components and supports had only two divisions: Division 1, for metal
construction, and Division 2, for concrete construction. Division
3 was added to cover the containments of packaging for nuclear
materials. Currently, the scope for Division 3 is limited to transportation and storage containments for only the most hazardous
radioactive materials—namely, spent fuel and other highly radioactive materials, such as high-level waste. Division 3 contains
three published subsections: Subsection WA providing general
requirements, Subsection WB addressing rules for transportation
containments, and Subsection WC addressing storage containment
rules. Subsection WD, which is scheduled to be published in the
2017 Edition of Section III, will provide the construction rules
applicable to internal support structures (baskets) for the transportation and storage containments covered by Subsections WB and
WC. Consistent with current Code practice, the primary concern
of Division 3 is the integrity of these containments under design,
operating conditions (including normal, off-normal, and accident),
and test conditions. In particular, the structural and leak-integrity
of these containments is the focus of the ASME B&PV Code rules.
Division 3 is also concerned with certain aspects of containmentclosure functionality because of the potential for leakage, which is
a key consideration in the containment function. Division 3 covers all construction aspects of the containment, including administrative requirements, material selection, material qualification,
design, fabrication, examination, inspection, testing, quality assurance, and documentation.
liv t Introduction
In Chapter 17, authored by Robert I. Jetter and D. Keith Morton,
a commentary is provided regarding the development of Section
III, Division 5. This Division was first issued in November 2011.
Currently, the scope for Division 5 is High Temperature Reactors,
addressing both high temperature gas-cooled reactors and high temperature liquid-cooled reactors. Division 5 identifies rules based
on only two classifications, Class A for safety-related components
and Class B for non-safety related but with special treatment components. Division 5 contains general requirements for both metals
and graphite in Subsection HA, Subpart A and Subpart B, respectively. Rules for Class A metallic pressure boundary components,
Class B metallic pressure boundary components, and Class A core
support structures at both low temperature conditions (under Subpart A) and elevated temperature conditions (under Subpart B) are
contained in Subsections HB, HC, and HG, respectively. Rules for
Class A and B metallic supports are contained in Subsection NF,
Subpart A. Finally, new rules for non-metallic core support structures (graphite) are contained in Subsection HH, Subpart A. Consistent with current Code practice, the primary concern of Division
5 is the integrity of these components under design, operating conditions (including normal, upset, emergency, and faulted), and test
conditions. Division 5 covers all construction aspects of these components, including administrative requirements, material selection
and qualification, design, fabrication, examination, inspection, testing, quality assurance, and documentation.
The discussion of Subsection NH, (Class 1 Components in
Elevated Temperature Service) previously covered in Chapter 12
has been moved to Chapter 17 because Subsection NH has been
incorporated into Section III, Division 5. In Section III, elevated
temperature is defined as 700°F for ferritic steels and 800°F for
austenitic stainless steels and nickel-base alloys. Elevated temperature behavior and associated failure modes are discussed to
provide background for the unique features of the elevated temperature rules. The authors presume that readers have a basic
familiarity with the rules for construction of Classes 1, 2, and 3
components and core-support structures contained in Subsections
NB, NC, ND, and NG, respectively, that are discussed in other
chapters of this book. Thus, cross-referencing to these Code Subsections is provided. Based on 40-plus years in the development
and implementation of elevated temperature design and construction rules, the authors, with the aid of figures, tables, and references, provide a historical perspective to establish the criteria for
the rules for metallic structures previously contained in Subsection
NH, now in Section III, Division 5. Also discussed are current and
future needs.
Chapter 18, was authored by M. A. Malek and John I. Woodworth
for the first edition, and co-authored by Geoffrey M. Halley for
the Second edition. The third and fourth edition has been revised
by Edwin A. Nordstrom. The current fifth edition was revised by
Clayton T. Smith. In the first edition, the chapter covered Section
IV, Rules for Construction of Heating Boilers, using the 1998 Edition, 1999 Addenda, and Interpretations and has now been updated
to the 2015 edition. To assist the reader in understanding and using
the Code, this chapter is presented in a simplified manner, with
the understanding that it is not a Code book and is not written to
replace the Code book published by ASME. A historical perspective of Section IV is provided to trace the criteria covered by the
Code. The authors define the boilers that fall within the jurisdiction of this Section and provide a detailed discussion of the minimum requirements for the safe design, construction, installation,
and inspection of low-pressure-steam boilers and hot-water boilers, which are directly fired with oil, gas, electricity, or other solid
or liquid fuels. However, the authors do not cover the operation,
repair, alteration, rerating, and maintenance of such boilers, but
they do cover potable-water heaters and water-storage tanks for
operation at pressures not exceeding 160 psi and water temperatures not exceeding 210°F.
In the first edition, Chapter 18 addressed the Code Interpretations, the Addenda, and the Code Inquiry procedure as they relate
to Section IV. The authors mentioned that the format used for this
chapter is compatible with the format used in Section IV (1998
Edition, 1999 Addenda, and Interpretations). For the current edition using the 2015 Code, this is still valid. For easy identification, the exact numbers of paragraphs, figures, and tables from the
Code book have been used in the running text. The appendices
include Method of Checking Safety Valve and Safety Relief Valve
Capacity; Examples of Methods of Calculating a Welded Ring
Reinforced Furnace; Examples of Methods of Computation of
Openings in Boiler Shells; Glossary; and two examples of Manufacturer’s Data Report Forms.
Chapter 19 provides criteria and commentary for ASME Section VI, Recommended Rules for the Care and Operation of Heating Boilers. This chapter that had been initially authored by M. A.
Malek was updated for the second edition by Geoffrey M. Halley,
Edwin A. Nordstrom was as the author of the third and fourth edition, and Clayton T. Smith updated the current 5th edition. While
heating boilers are designed and constructed safely under Section
IV, the rules of this Section are nonmandatory guidelines for the
safe and efficient operation of steam-heating boilers, hot-watersupply boilers, and hot-water-heating boilers after installation.
These rules, however, are not applicable to potable-water heaters.
This chapter is divided into nine parts, along with the necessary
figures and tables for each part: General, covering the scope, use of
illustrations, manufacturer’s information, references to Section IV,
and glossary of terms; Types of Boilers; Accessories and Installation; Fuels; Fuel-Burning Equipment and Fuel-Burning Controls;
Boiler-Room Facilities; Operation, Maintenance, and Repair of
Steam Boilers and Hot-Water Boilers; and Water Treatment. The
authors have several years of professional field experience in overseeing Code implementation and are conversant with regulatory
practice; as such, they discuss the jurisdictional responsibilities and
role of licensing agencies.
The authors note that the format used for this chapter is compatible with the format used in Section VI 2015 Code Edition. For
easy identification, the exact numbers of paragraphs, figures, and
tables from the Code book have been used in the running text. The
Exhibits include the maintenance, testing, and inspection log for
steam-heating boilers and the maintenance, testing, and inspection
log for hot-water-heating boilers and tests. Bibliographical references and notes are also provided.
Chapter 20 was initially authored by Harold C. Graber and the subsequent second edition and third edition were revised by Jon Batey.
The current fifth Edition was authored by G. Wayne Hembree. The
authors discuss Section V, Nondestructive Examination (NDE).
The purpose of this chapter is to provide Users of Section V
insight into the significant requirements, the NDE methods, the
NDE methodology, the relationship of Section V with other Code
Sections, and the use of ASTM Standards. The information provided is based on the 2015 Edition of Section V, dated July, 2015.
The charter and scope of this Section is to develop and maintain Code rules for NDE methodology and equipment involved
with the performance of surface and volumetric testing methods.
These examination methods are used for the detection and sizing
of defects, discontinuities, and flaws in materials and weldments
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t lv
during the manufacture, fabrication and construction of parts,
components, and vessels in accordance with the ASME B&PV
Code and other ASME Codes, such as B31.1 (Power Piping).
Harold, Jon and Wayne provide commentary on the contents
of Section V, including Subsection A, which contains Articles
and both Mandatory and Nonmandatory Appendices that address
general requirements, examination methods, and specific Code
requirements and acceptance criteria; and Subsection B, which
contains the ASTM Standards adopted by the ASME B&PV Code.
This chapter addresses an audience that includes manufacturers (including equipment manufacturers), insurance companies,
architect-engineers, research organizations, utilities, consultants,
and the National Board. The authors address additions, revisions, inquires, interpretations, and Code Cases relevant to Section V. An important aspect of this chapter is its coverage of the
interconnection of Section V with other Code Sections and Subsections. This coverage provides insight into how the relationships of
the Code Sections are integrated.
VOLUME 2
Chapter 21 initially authored by Urey R. Miller has been revised
by Thomas P. Pastor and Jayaram Vattappilly for the current fifth
edition. This chapter covers Section VIII, Division 1, Rules for
Construction of Pressure Vessels. The author discusses the historical background of this Section in relation to the construction and
safe operation of boilers and pressure vessels.
Section VIII, Division 1 is written to cover a wide range of industrial and commercial pressure vessel applications. This Section is
applicable to small compressed air receivers as well as to very large
pressure vessels needed by the petrochemical and refining industry.
Section VIII Division l is intended for the construction of new pressure vessels. Miller discusses the applicability of Code and Code
jurisdictions, as well as situations of the inapplicability and exemptions from this Section. This chapter provides an overview to each
of the parts of Section VIII, Division 1 Code. The commentary
includes Subsection A-General Requirements for All Methods of
Construction and Materials; Subsection B-Requirements Pertaining to Methods of Fabrication of Pressure Vessels; Subsection C—
Requirements Pertaining to Classes of Material; Mandatory Appendices; Non-Mandatory Appendices; and Bibliography. The intent
of the author is to provide a broad perspective for the reader to
have better understanding of the Codes intent, and to point out, by
example, some of the subtleties that may not be evident. It is not
the objective of this Chapter to provide the reader with a detailed
“how to” handbook. The user of the equipment must define the
requirements that are needed for a specific application. With the
help of equations, tables, figures and examples Miller provides
detailed commentary of Section VIII, Division l. He comments
about several pertinent Code Interpretations and Code Cases pertaining to this Section.
There have been a number of significant changes to Section VIII
Division l since the First Edition of this Guidebook. The most significant is that the previously non-mandatory rules for tubesheets
(Appendix AA) and flanged and flued expansion joints (Appendix CC) are now mandatory and are in Part UHX and Appendix 5
respectively. Also, a new mandatory appendix (Appendix 32) has
been added to the Code to allow consideration of local thin spots
in shells and heads, and Appendix 33 has been added to define the
standard units to be used in Code equations. The 2nd Edition of the
Guidebook was updated to cover the ongoing Code revisions that
affect shell-to-tubesheet joints, Appendix 26 expansion joints and
Appendix M.
The Third Edition of the Guidebook covers revisions to Section
VIII, Division l from the 2004 Edition through the 2007 Edition.
Included are detailed descriptions of several new Nonmandatory
Appendices, including Appendix FF: Guide for the Design and Operation of Quick-Actuating (Quick Opening) Closures, and Appendix
GG: “Guidance for the Use of U. S. Customary and SI Units in the
ASME Boiler and Pressure Vessel Code”. This Chapter also includes
extensive updating of referenced figures and tables from the 2007
Edition of Section VIII, Division I.
The Fourth Edition of the Guidebook covers revisions to Section VIII. Division I from the 2007 Edition, 2008 Addenda through
the 2010 Edition, 2011 Addenda. Included is a detailed description of Code Case 2695 which will allow a Section VIII, Division
1 Certificate Holder to use the design rules of Section VIII, Division 2 Part 4 for the design of VIII-1 vessel. This Code Case is
ground breaking in that it represents the first step in a long range
plan by the Section VIII Committee to encourage pressure vessel
manufacturers to consider using Section VIII, Division 2 for the
design of custom engineered vessels. Also covered is the move by
ASME to utilize a single mark in place of the current 28 stamps
that are used with the different pressure equipment accreditation
programs. A detailed description of the new Part UIG, Requirements for Pressure Vessels Constructed of Impregnated Graphite,
is provided, as well as the expanded set of requirements covering
mass production of pressure vessels in Appendix 35. Similar to
the Third Edition, numerous Figures and Tables have also been
updated.
The Fifth Edition of the Guidebook covers revisions to Section
VIII, Division 1 from the 2013 and 2015 Editions. Some of the
more significant changes to Section VIII, Division 1 include a new
paragraph UG-6, that provides explicit rules for use of forgings
in the construction of pressure vessels. Specifically this paragraph
will now permit tubesheets and hollow cylindrical forgings to be
fabricated from SA-105 with some additional requirements. In the
pressure test area, rules were introduced in UG-99 and UG-100
concerning restrictions on painting or coating a vessel prior to
the pressure test. Another major change involves the removal of
all Conformity Assessment requirements from UG-117; these
requirements now directly referenced to a new ASME standard
titled “Conformity Assessment Requirements – CA-1”.
A new Appendix, Appendix 43: Establishing Governing Code
Editions and Cases for Pressure Vessels and Parts, was added.
These new mandatory rules now clearly define what Edition must
be used for construction of pressure vessels and parts. Finally a
new nonmandatory appendix, Appendix NN: Guidance to the
Responsibilities of the User and Designated Agent, has been added.
In all there are over 80 references to the User and/or Designated
Agent in Section VIII, Division 1. Appendix NN addresses the
important responsibilities of the User, and provides a convenient
cross-reference table to all of the paragraphs in the Code where the
User is cited.
Chapter 22 has been revised by David A. Osage, Thomas P. Pastor,
Clay D. Rodery, Philip A. Henry, and James C. Sowinski for the current fifth edition. This chapter covers Section VIII, Division 2, Rules
for Construction of Pressure Vessels, Alternative Rules. The authors
have updated the applicable sections in accordance with the 2015
Edition of Section VIII, Division 2.
Since its introduction in 2007 as a re-written, technologically
advanced, and modernized standard, Section VIII, Division 2 has
continued to evolve. As covered in Chapter 22, the authors have
lvi t Introduction
highlighted significant changes made to Section VIII, Division 2
including:
Part 2 updates to the User’s Design Specification to reflect
changes for fatigue design life, changes to the Quality Control System, updates and relocation of related requirements to conformity assessment from Annex 2-G to a new ASME standard titled
“Conformity Assessment Requirements—CA-1, and the introduction of Annex 2I Establishing Governing Code Editions and Cases
for Vessels and Parts;
Part 3 introduced a new paragraph for the material Design Values for Temperatures Colder than –30°C (–20°F) and updates to
Annex 3.F which introduced new smooth bar curve-fit equations
and corresponding fatigue life curves;
Part 4 introduced design rules for flanged-and-flued or flangedonly expansion joints, new Annexes regarding deflagration loading and tube expanding procedure qualifications, one general set of
equations applicable to both hydrostatic and pneumatic test conditions, and updates to design load considerations and design load
combinations;
Part 5 also includes updates to design load considerations, and
design load combinations for elastic, limit load, and plastic analysis;
Part 6 significant changes include incorporation of requirements
to cover creep enhanced ferritic steels, new equations for calculating forming strains, and the introduction of an informative annex
on positive material identification;
Part 7 updates to requirements for qualification of nondestructive personnel, tables which address the extent and location of nondestructive examination, and extended flaw acceptance criteria to
welds;
Part 8 changes include the introduction of general equations for
hydrostatic and pneumatic testing with variables to provide for
flexibility of incorporating alternate design margins for future reference; and
Part 9 updates to Annex 9.A regarding Best Practices for the
Installation and Operation of Pressure Relief Devices.
Chapter 23, authored by J. Robert (Bob) Sims, Jr. and Charles
(Chuck) Becht V, discusses Section VIII, Division 3 (Alternative
Rules for the Construction of High-Pressure Vessels). It is intended
to be used as a companion to the Code by Manufacturers and Users
of high-pressure vessels and also provides guidance to Inspectors,
materials suppliers, and others. The chapter’s text is generally presented in the same order in which it appears in the Code. Comments
are not given about each Paragraph, but Paragraph numbers are
referenced as appropriate. The comments apply to the 2015 Edition. The ASME Subgroup on High-Pressure Vessels (SG-HPV) of
Subcommittee VIII developed the Code. The comments herein are
Bob’s and Chuck’s opinions; they should not be considered Code
Interpretations or the opinions of the Subgroup on High-Pressure
Vessels or any other ASME Committee.
This chapter provides commentary that is intended to aid individuals involved in the construction of high-pressure vessels, but it
cannot substitute for experience and judgment. Bob covers general,
material, and design requirements; supplementary requirements
for bolting; special design requirements for layered vessels; design
requirements for attachments, supports, and heating and cooling
jackets; fracture mechanics evaluation; design using auto-frettage;
special design requirements for wirewound vessels and frames;
design requirements for openings, closures, heads, bolting, and
seals; scope, jurisdiction and organization of Division 3; fatigue
evaluation; pressure-relief devices; examination, fabrication, and
testing requirements; marking, stamping, reports, and records; and
Mandatory and Nonmandatory appendices.
Chapter 24 was previously an Appendix to Part 7, has been
authored by Roger Reedy. This Chapter written by Roger F. Reedy
deals with the Safety of Personnel Using Quick-Actuating Closures
on Pressure Vessels and Associated Litigation Issues.
Chapter 24 was written because of the number of lawsuits
against manufacturers of quick-actuating closures on pressure
vessels. Often manufacturers are sued even though the closures
had been operating with no accidents for 20 or 30 years. Because
of Worker’s Compensation rules, the owner of the equipment
often cannot be sued, so the lawyers search for “deep pockets” to
compensate their clients and themselves. In order to bring forth
litigation, these lawyers would skillfully take words in the Code
completely out of context. The Appendix is based on Roger’s
personal experience in a number of litigations involving quickactuating closures during the last 25 years. He identifies each
of the changes made to the Code rules in Section VIII, Division
1, from 1952 to the 2007 Edition of the ASME Code. In every
case where Roger has testified as an expert witness, the manufacturer of the quick-actuating closure was not at fault, and the
ASME Code rules had been properly followed. However, some
attorneys for the injured party may misinterpret the Code rules to
accuse the manufacturer of not having complied with the Code
when the closure was made. Based on experience, Roger warns
the writers of the ASME Code to assure that the rules are clear,
concise and understandable to the common man. The most important point however, is for everyone to understand that in order
to avoid severe accidents, users of quick-actuating closures must
maintain the equipment and ensure that inferior components are
not used as replacement parts, and that the design is not modified
or changed in any way. The other key element for safety is that
owners of pressure vessels that have quick-actuating closures are
responsible for training all employees regarding the proper care
and use of the equipment. This training has been neglected by the
employer in most accidents.
Further, it is extremely important that the closure and all the
equipment associated with the closure be continually maintained by
the user. In almost every litigation associated with quick-actuating
closures, the user (company) failed in training employees and maintaining equipment. In an important New Jersey lawsuit in 2011, the
jury cleared the manufacturer from any liability for the cause of
a worker’s severe injuries, when he improperly forced the closure
open by hammering it with a small sledge hammer.
The chapter has been updated and editorially modified and identifies that the rules in Section VIII, Division 1 will incorporate
many of the suggestions identified in this chapter. New rules for
quick-actuating closures on pressure vessels will be published in
the 2017 Edition.
Chapter 25, originally authored by Joel G. Feldstein, and now
updated by John P. Swezy, Jr., discusses Section IX, Welding,
Brazing, and Fusing Qualifications. As the title indicates, this
chapter deals with the qualification of welding, brazing and fusing
procedures as well as the qualification of individuals performing
those procedures as required by the Construction Codes of the
ASME B&PV and Piping Codes. Joel and John discuss the organization of the 2015 Edition of Section IX: Part QG, covering the
general requirements applicable to all joining methods, Part QW,
covering welding, Part QB, covering brazing, and Part QF, covering Plastic Fusing. Each of the Parts which address a specific
joining process are divided into four Articles. The development
of Part QG sought to consolidate requirements which are applicable to all material joining methods in a centralized location, while
leaving general requirements that are unique to a specific material
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t lvii
joining process within their respective Parts. The coverage for Part
QW includes general requirements for both welding procedure and
welder performance qualification and the variables applicable to
welding procedure and welder performance qualification. Part QB
has a similar format: general requirements for brazing procedure
and brazer performance qualification and the variables applicable
to brazing procedure and brazer performance qualification. Part QF
follows the established model, by discussing general requirements
for fusing procedure and fusing machine operator performance
qualifications, and identifying the variables applicable to fusing
procedure and fusing machine operator performance qualification.
Commentary is provided for each of the Articles with the aid of
figures and tables, and Code Interpretations are used to provide the
Code User with some insight into the requirements of Section IX.
Joel provides a description of the more common welding processes
used in Code construction, reviews the qualification rules, provides commentary on those requirements, and covers the historical
background leading to the increased use of welding in manufacturing operations. John introduces the plastic fusing process for joining high density polyethylene (HDPE) piping, and describes the
qualification rules for this joining process and its various modes of
application. Where comments are provided, they represent Joel’s
and John’s opinions, and should not be regarded as the positions of
the ASME Code or its Standard Committee on Welding.
In Chapter 26 Bernard Shelley covers Section X, Fiber-Reinforced
Plastic Pressure Vessels, and ASME RTP-1, Reinforced Thermoset
Plastic Corrosion-Resistant Equipment. The author mentions that
this chapter is tailored for engineers and designers whose experience
with vessels is primarily with metal equipment, although he adds
that those with experience using fiberglass equipment but not using
Section X or RTP-1 will also find this chapter useful, especially its
discussions on fiber-reinforced plastic (FRP) technology. Section X
has been enacted into law in 37 jurisdictions in the United States
and Canada, whereas RTP-1, although usable as a Code, has been
enacted into law in only one state (Delaware), and; therefore, at present, it is a voluntary Standard in most jurisdictions. Both Standards
govern vessels constructed of thermosetting resin reinforced with
glass fibers, but Section X addresses vessels reinforced with carbon
or aramid fibers as well. The pressure scope of Section X is 15 psig
internal pressure up to 15,000 psig. RTP-1 covers tanks and vessels
with design pressures of 0 to 15 psig. Both Standards have provisions for vessels with external pressures of full vacuum to 15 psig.
Neither RTP-1 nor Section X is meant to be handbook or textbook on FRP vessel design. Chapter 26 is intended to be a manual
on the use of these documents. An engineer who specifies an FRP
vessel does not need to understand FRP to the same extent that a
vessel designer does; however, in specifying the vessel, an engineer necessarily makes many design choices. Bernie discusses the
basics of FRP technology; the fabrication methods and stress analysis of FRP vessels; the scope of Section X and RTP-1; the design
qualification of Section X, Class I, Class II, Class III, and RTP-1
vessels; the design qualification overview; Section X example of a
Design Specification and its calculations; RTP-1 design examples;
and quality assurance of Section X and RTP-1. He provides equations, tables, and figures as well as annotated bibliographical notes
indicating the relevance of the cited references.
In Chapter 27, Gary Park and Douglas Scarth provide an overview of the stipulations of Section XI, Rules for Inservice Inspection
of Nuclear Power Plant Components. A chronological overview of
the development of Section XI is presented, from its inception in
1968 up to the 2015 Edition. The chapter traces the development,
Edition-by-Edition, of important elements of the Code, including
the philosophy behind many of the revisions. Through an extensive tabulation of Code Interpretations, this chapter also attempts
to give the Code User some insight into clarification of many Section XI requirements. In the more recent revisions of Section XI,
feedback from operating plants has resulted in new requirements
to address stress corrosion cracking and other corrosion related
mechanisms, weld overlay and other piping repair techniques, and
revisions to inspection and test requirements to address a number
of other current issues.
The authors note that subsequent chapters of this book address the
major areas of Section XI: inservice inspection examination and test
programs, repairs and replacements, acceptance and evaluation criteria, containment programs, and fatigue crack growth. Non-destructive
examination (NDE) is addressed in this chapter, as its requirements
evolve. The authors mention that Section XI initially had only
24 pages in 1970 but that it now has over 600 pages. Although originally it covered only light-water reactor Class 1 components and piping, now it includes Class 2 and Class 3 systems, metal and concrete
containment, and liquid metal cooled reactor plants. With their association with Section XI Code Committee activities for a significant
number of years, the authors are in a good position to comment on
important areas that should not be overlooked.
In Chapter 28, Richard W. Swayne addresses the requirements of
IWA-4000 for repair/replacement (R/R) activities for nuclear power
plant items. Rick examines the background of these R/R activities
and the changes in R/R activity requirements since the original
1970 Edition, and reviews in detail the requirements in IWA-4000
in the 2015 Edition of Section XI. This information is beneficial to
personnel performing R/R activities (e.g., designing plant modifications, obtaining replacement items, and performing welding, brazing, defect removal, installation, examination, and pressure-testing
activities). Although the 2015 Edition is used to discuss IWA-4000
requirements, discussions involving earlier editions and addenda of
Section XI have been retained from previous editions of the Companion Guide. The thorough discussion of changes from earlier
editions and addenda will be very beneficial to personnel using earlier editions and addenda, especially those updating their Repair/
Replacement Programs.
In Chapter 28, Mr. Swayne uses his unique professional expertise to discuss R/R activity requirements and provides the basis and
pertinent explanations for the requirements. The discussion of the
scope and applicability of Section XI R/R activities is informative
to both new and longtime users. Rick notes that Section XI is used
in many countries, such that it is often recognized as an international Standard. Therefore, he has written Chapter 27 such that it
applies regardless of the country where the Section is used. To benefit the reader, numerous Code Interpretations and Code Cases are
included in this chapter to help clarify and implement R/R activities. Commentary is provided regarding Interpretations that might
be of great benefit in understanding the Code. With over 25 years
of association with Code Committee activities, Mr. Swayne provides clarity and in-depth understanding of Section XI.
Chapter 29, authored by Richard W. Swayne, discusses the Section XI rules for inservice inspection and testing of nuclear power
plant components. This chapter covers the general requirements
of Section XI applicable to all Classes of components, including
concrete structures and steel vessels, piping, pumps, and valves.
It identifies the limits of applicability of Section XI, that is, what
is within and outside the scope of the Code. Interfaces with applicable regulatory requirements are addressed, and use of Code Editions, Addenda, and Cases is explained. Mr. Swayne comments on
the periodic NDE and pressure testing required to ensure integrity
lviii t Introduction
of components, other than containment vessels, within the scope of
jurisdiction of this Code. These requirements include NDE, from
personnel qualification to conduct of the NDE. They also include
the type and frequency of NDE required, including sample expansion and increased frequency required because of defect detection.
Mr. Swayne also addresses periodic pressure testing and pressure testing following R/R activities. Responsibilities and quality
assurance program requirements of the different entities involved
in examination and testing of a nuclear power plant are discussed.
This chapter addresses many controversial issues and topics of
current concern, including the applicability of recent U.S. Nuclear
Regulatory Commission (NRC) Generic Letters and Information
Notices, and describes ways in which readers can use recent revisions of Section XI to their advantage. References to ASME Interpretations are included to explain how the Code requirements can
be applied to common problems. This Edition contains new information from Mr. Swayne on risk-informed inservice inspection
and reliability integrity management programs for non-light-water
reactors.
In Chapter 30, which was originally written by Arthur F. Deardorff,
and updated and expanded by Russell C. Cipolla, the flaw acceptance criteria and evaluation methods specified in the 2007 Edition
through 2015 Edition, of ASME Section XI Code are discussed.
Coverage includes the evaluation of flaws in nuclear power plant
components and piping using ASME Section XI procedures. The
authors discuss flaw acceptance criteria based on the use of predefined acceptance standards and of detailed fracture-mechanics
evaluations of flaws. Commentary is provided on flaw characterization and acceptance standards, Class 1 vessel flaw evaluation, piping flaw evaluation (for austenitic and ferritic materials),
and evaluation of piping thinned by flow-assisted corrosion. The
authors discuss the background and philosophy of the Section XI
approach for evaluating inservice degradation, including the rules
for inservice inspection of nuclear power plant components and
piping as they relate to the criteria, to determine if flaws are acceptable for continued operation without the need for repair.
Drawing upon their participation in Code Committees and professional experience with both domestic and international nuclear
plants, the authors discuss step-by-step procedures for the evaluation of flaws in austenitic and ferritic components and piping.
The underlying philosophy of Section XI evaluation of degraded
components is to provide a structural margin consistent with that
which existed in the original design and construction code. Russ
has expanded the chapter to describe the updated flaw evaluation
procedures for piping, which were added to Section XI in 2002.
Also discussed are revised flaw acceptance criteria for Class 1 ferritic vessels in IWB-3610, updated structural factors for austenitic
and ferritic piping in Appendix C, and revised fatigue crack growth
reference curves (e.g., Code Case N-809 for fatigue crack growth
in austenitic stainless steel in PWR environments), along with the
technical basis for these changes.
Russ has also added the historical development and technical
basis for Appendices E, G and K, which deal with evaluations for
fracture prevention during operating plant events/conditions in
the fracture-toughness transition temperature region, and at upper
shelf. Further, recent Code Cases N-513 and N-705 to Section XI
are described, including new revisions, which cover the requirements and procedures for temporary acceptance of service induced
degradation in piping and vessels in moderate energy Class 2
and 3 systems. The degradation can be associated with various
mechanisms (cracking, pitting, general wall thinning, etc.) and can
include through-wall degradation where leakage can be adequately
managed via monitoring. These Cases provide the basis for continued operation until repair can be implemented at a later time.
In addition, this chapter has been updated to discuss very recent
and future developments in flaw evaluation methodologies for
components and piping to include improvements in calculations
techniques, material reference curves, and flaw acceptance criteria.
Wherever possible, the authors cite references to published documents and papers to aid the reader in understanding the technical
bases of the specified Code flaw evaluation methods and acceptance criteria. The authors also cite related Section XI requirements
that are discussed in other chapters of the Companion Guide.
This is the fourth update of Chapter 31 authored by Jim E.
Staffiera (this Chapter in the 1st Edition of the Guide was authored
by the late Robert F. Sammataro). Chapter 31 addresses ASME
Code Section XI, Subsections IWE and IWL, for nuclear power
plant containments. Subsection IWE, Requirements for Class MC
and Metallic Liners of Class CC Components of Light-WaterCooled Plants, specifies requirements for preservice and inservice
examination/inspection, repair/replacement activities, and testing
of Class MC (metal containment) pressure-retaining components
and their integral attachments and repair/replacement activities
and testing of Class CC (concrete containment) pressure-retaining
components and their integral attachments for BWRs and PWRs.
Similarly, Subsection IWL, Requirements for Class CC and
Metallic Liners of Class CC Concrete Components of Light-Water
Cooled Plants, specifies requirements for preservice and inservice
examination/inspection, repair/replacement activities, and testing
of the reinforced-concrete and post-tensioning systems of Class
CC (concrete containment) components for BWRs and PWRs.
Together with Subsection IWA, General Requirements, a comprehensive basis is provided for ensuring the continued structural and
leak-tight integrity of containments in nuclear power facilities.
Subsections IWE and IWL also provide requirements to ensure
that critical areas of primary containment structures and components are examined to detect degradation that could compromise
structural integrity. These two Subsections received significant
industry attention once the U.S. Nuclear Regulatory Commission (USNRC) mandated nuclear-industry compliance with these
requirements through revision of Paragraph 50.55(a) of Title 10,
Part 50, of the Code of Federal Regulations [10 CFR 50.55(a)] in
September 1996. In incorporating Subsections IWE and IWL into
the regulations, the NRC identified its concern with the increasing
extent and rate of occurrence of containment corrosion and degradation. Since that time of initial incorporation, numerous changes have
taken place in all aspects of nuclear power plant inservice inspection requirements. With increasing industry emphasis on plant life
extension, these changes have resulted in several initiatives currently
moving through the ASME Code ‘consensus-committee’ process,
including action items addressing the need for more appropriate and
effective examinations/inspections and the expanded use of riskinformed inservice inspection activities.
This 5th-Edition Update of Chapter 31 includes a brief history of
the development of ASME Code requirements (with emphasis on
the development of inservice inspection requirements for nuclear
power plant containments), the latest information on USNRC regulatory review and incorporation of recent ASME Code Editions
and Addenda, and current listings of U.S. ‘construction-complete’
commercial nuclear power plants and their containment types and
operating status. A summary of recent nuclear industry developments in advanced plant designs and a discussion of the as-yetunrealized ‘U.S. nuclear renaissance’ are also presented, along
with information on the global demand for energy and the current
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t lix
status of commercial nuclear power around the world. Lastly, the
current Subsection IWE and IWL Commentaries, as approved
and maintained by the ASME Working Group on Containment
(WGC), are included as attachments to Chapter 31. These Commentaries are important documents for users of the Code because
of the background information provided and the technical justification for changes made to these two subsections over the years.
However, users are cautioned that these Commentary documents
are the collective opinions of WGC members only and, although
approved by WGC, are not products of the ASME Code ‘consensus-committee’ process. As such, the Subsection IWE and IWL
Commentaries are not part of the ASME Code, nor do they represent the official position of any ASME Code Committee.
In Chapter 32, Warren H. Bamford discusses the Code evaluation
of fatigue crack growth, consistent with the evaluation methods of
Section XI. Fatigue has often been described as the most common
cause of failure in engineering structures, and designers of pressure
vessels and piping have incorporated fatigue considerations since
the first Edition of Section III in 1963. The development of this
technology and its application in Section III is discussed in Chapter 39 of third edition; its application in Section XI is discussed in
Chapter 32. With the advancement of the state of the art has come
the capability for allowing the presence of a crack, for predicting
crack growth, and for calculating the crack size that could lead to
failure. This capability has been a key aspect of the Section XI flaw
evaluation procedures since the 1974 edition of Section XI; it is
discussed thoroughly in Chapter 32.
Warren discusses the background of the criteria for fatigue crack
growth analyses and crack growth evaluation methods. Drawing
upon his considerable experience in formulating these criteria
and his professional expertise in these analyses and evaluations,
Warren provides commentary on the calculation of crack shape
changes; calculation of elastic–plastic crack growth with the aid of
crack growth rate reference curves for ferritic and austenitic steels
in air environments; and crack growth rate curves for ferritic and
austenitic steels in water environments. The fifth edition contains
an update on the recent revision of fatigue crack growth of austenitic steels in PWR environments, as well as treatment of SCC
growth for austenitic steels in BWR environments. He also discusses operating plant fatigue assessment with the aid of Appendix L of Section XI. Also included are discussions pertaining to
Appendix A, fatigue evaluation, and flaw tolerance evaluation. He
provides extensive bibliographical notes and references.
Chapter 33, authored by Hardayal Mehta and Sampath Ranganath,
recognized authorities on the Elastic-Plastic Fracture Mechanics
(EPFM), are providing in this chapter a review of EPFM applications
in ASME Section XI Code. The early ASME Section XI flaw evaluation procedures have been typically based on LEFM. Early progress
in the development of EPFM methodology is first reviewed. A key
element in the application of EPFM to flaw evaluation is the estimation of the fracture parameter J-Integral. Therefore, the applied J-Integral estimation methods developed by EPRI/GE are first reviewed.
Basics of the J-T stability evaluation are then discussed. The first
application of EPFM methodology to flaw evaluation of austenitic
piping welds is discussed. The extension of EPFM techniques to flaw
evaluations in ferritic piping is then covered. Technical background
and evolution of Section XI Code Cases (N-463, N-494) and nonmandatory Appendices (C and H) related to pipe flaw evaluation is
then provided. Another EPFM based pipe flaw evaluation procedure
using the so-called DPFAD approach is also covered.
Drs. Mehta and Ranganath then describe the application of EPFM
methods to the flaw evaluations of reactor pressure vessel. An early
application has been the evaluation of RPVs with projected upper
shelf energy less than that required by 10CFR50. The technical
background of Section XI Code Case N-512 and non-mandatory
Appendix K is provided. Finally, a proposed Code Case currently
under consideration by appropriate Section XI Working Groups, is
discussed in detail that would permit the use of EPFM methodology for RPV flaw evaluations per IWB-3610. The updated chapter
considers the developments up to 2010 ASME Code as they relate
to EPFM flaw evaluation methods discussed. Incorporation of direct
use of Master Fracture Toughness Curve in EPFM evaluations, such
as in the ASME Code Case N-830, is briefly described. The current
activity within the ASME Section XI Code Groups related to the
potential revision of N-830, is summarized.
The authors have included extensive bibliographical references
from their own publications, research publications, international
journals and related EPRI and ASME publications.
Chapter 34, initially authored by Mahendra D. Rana, Stanley
Staniszewski provide a Description of Rules of ASME Section XII
covering Transport Tank Code of the 2007 edition.
This chapter was revised by Mahendra D. Rana and Stanley
Staniszewski to incorporate the latest Code changes in 2010 edition. This Code provides rules for construction and continued service of pressure vessels used in transportation of dangerous goods
via highway, rail, air or water.
The authors provide an overview of Section XII while covering
specific topics such as the scope and general requirements, materials and design, fabrication, inspection and testing requirements.
The need for a pressure vessel code dealing with the whole spectrum of tanks to transport dangerous goods was a result of the review
of USDOT (U.S. Department of Transportation) regulations.
The regulations had become cumbersome to use, and in a global
market without compromising safety the need to make the rules for
transport tanks acceptable internationally became urgent. Hence
the inaugural edition of ASME’s Section XII focus was Portable
Tanks. The subcommittee prepared the Code to be transparent with
existing ASME Code requirements such as Section VIII, Div. 1,
while including the existing DOT requirements that impacted the
scope of the charter to prepare the Section XII Code.
This chapter had been coordinated by Mahendra Rana with
the help of experts covering topics in their respective fields. Stan
Staniszewski dealt with the scope and general requirements of the
Code including rules on pressure relief devices, stamping, marking
certification, reports and records. The scope of the Code applies
to pressure vessels 450L and above, including additional components and criteria addressed in Modal Appendices that are to be
used along with applicable regulations and laws. Mahendra Rana
revised the sections on fabrication, inspection and testing requirements of Section XII 2010 edition. From the perspective of fabrication and inspection, Section XII is a mixture of familiar and
new concepts to the Section VIII Division 1 Boiler and Pressure
Vessel Code. Mahendra Rana covered the sections on materials
and design rules. The coverage included Design Conditions and
Allowable Stresses, Design Temperatures, Design and Allowable
Working Pressures, Loadings, Design of Formed Heads, Torispherical Heads, External Pressure Design, Flat Heads and Covers,
Openings and Reinforcements, Design of Welded Joints, and Articles covering Portable Cryogenic Tanks including Materials and
Design. The rules for fatigue design are also given in the article
covering Portable Cryogenic Tanks. Information on new coldstreched vessel technology has been incorporated in this chapter.
As in the 2017 Edition Code revision, Chapter 34 was further
updated with revised toughness rules for high alloyed steels, a new
lx t Introduction
Code Case that allows using 1% yield strength of austenitic stainless steels as the basis for allowable stresses, designs with higher
compressive allowable stress for shell and heads, and updated rules
on UT in lieu of RT with less restrictive thickness limitations.
Chapter 35 authored by Jimmy Meyer and Joe Frey covers the
Power Piping Code. The chapter is based on the 2016 edition of
the ASME B31.1 Power Piping Code. The chapter is written with
the assumption the reader has an edition of the Power Piping Code
at hand. The intention of the chapter is to supplement and provide
additional insight to the proper use of the code. Frequently referenced is how the Power Piping Code interfaces with other codes
and standards, both in the B31 series as well as other ASME, API,
AWWA, ASTM, et cetera.
Chapter 36 also authored by Jimmy Meyer covers the ASME
B31.3 Process Piping Code as well as the ASME B31.5 Refrigeration, B31.9 Building Services. Also addressed are a few new
standards in the ASME B31 series including ASME B31E Seismic
Design, B31J Stress Intensification Factors and B31.T Toughness
Requirements. The chapters are written based on the assumption the
various codes are at hand, however for some of the newer standards,
enough information is given to provide the user a good idea if they
are required for their specific activities.
Chapter 36A is the largest of the subchapters and it primarily
addresses the Process Piping Code, however it does give insight
into how the other documents are related and used to supplement
the requirements in ASME B31.3. The object of the chapter is not
to repeat the Process Piping Code, but rather to provide additional
insight into why it is organized the way it is and provide the reader
a better understanding of why some of the chapters and requirements are there. Frequent references are provided for the reader
who would like to explore a topic in more depth, likewise a number of simplified approaches are also provided to help the reader
understand the general principles associated with the requirements
of the Code(s).
Chapter 37, prepared by Michael Rosenfeld, discusses several
standards developed for oil, gas, or slurry transportation pipelines.
Standards for the design, construction, operation, and maintenance
of pipelines are represented by B31.4 and B31.8; standards associated with integrity management are represented by B31.8-S,
B31G, and B31Q. The technical basis for important differences
in design principles and practices between buried transmission
pipelines and above-ground piping (embodied in B31.1 and B31.3)
is examined in Chapter 37. These differences, which arise from
the unique needs of pipelines and the environment they operate in,
are profound and include allowable stress levels, material selection, and fabrication or installation requirements. It is also noted
that the two pipeline standards (B31.4 and B31.8) address operation and maintenance through the full life-cycle of the facility, an
important distinction from B31.1 and B31.3. Each of the pipeline
standards (B31.4 and B31.8), in turn, are tailored to suit the particular needs and attributes of their respective services. They share
many similarities among each other, but carry important differences as well, which are reviewed. Finally, pipelines operate in
the public. Failures can affect public safety and the environment,
and are not readily tolerated. A need and desire by the industry to
manage risk in an aging infrastructure has pushed the development
of technical standards that promote pipeline integrity management.
Historically this started with B31G, a manual for evaluate the
remaining strength of corroded pipelines. More recently, regulatory pressure led to the development of B31.8-S, a standard for
managing gas pipeline integrity, and B31Q, a standard for pipeline
operating personnel qualifications. These standards have gained
wide acceptance in the US and worldwide.
Chapter 38 provides an insight to ASME B31.12 Hydrogen Piping and Pipeline Code. This piping/pipeline code is ASME’s first
design code to be written for a specific fluid service. As such it
provides information about hydrogen system design along with
general piping and pipeline system design requirements.
Hydrogen interacts with carbon steel piping and pipeline systems in ways that can result in premature system failure. This code
has taken a conservative approach to system design that will provide a safe design. Material performance factors have been utilized
to take into account the effects of hydrogen embrittlement within
the range lowest service recommended service temperature up to
300°F (150°C) for carbon and low alloy steels. Currently stainless steels do not have any material performance factors provided
for their use in hydrogen systems. For service temperatures above
300°F (150°C), API 941 should be consulted for assistance in
material selection. Engineers are cautioned that hydrogen embrittlement cracking may occur during shutdown conditions for systems with service temperatures above the embrittlement range. The
only requirement for hydrogen embrittlement cracking is tensile
stress, hydrogen and time.
Chapter 39, new for this Edition and prepared by William K.
Sowder PhD, provides insight into the current and new approaches
for fusion energy being used today. These include experimental
facilities, new fusion construction projects and the next generation
fusion facilities. Due to the lack of relevant codes and standards
for use by the international fusion community the ASME Board
of Nuclear Codes and Standards (BNCS) approved the formation
and staffing of a new division to the ASME BPV Committee on
Construction of Nuclear Facility Components (III), Division 4
“Fusion Energy Devices”. This new division has five work groups.
Their membership is drawn from equipment manufacturers and
suppliers, users, international laboratories and currently involves
28 individuals developing these new fusion related code rules.
Countries represented in this effort include China, India, South
Korea, USA, UK and others within the EU.
In Chapter 40, Mr. Reedy identifies that the ASME Section III
Nuclear Code is completely compatible with Sections I and VIII.
Before the Nuclear Code was published, Code Cases for Sections I
and VIII were written for the first Nuclear Plants in the early
1950’s. Some plants used Section I and some used Section VIII.
In Chapter 40, these Code Cases are identified and explained. The
chapter also contains the original Commentaries for both Section III
and Section VIII, Division 2, which is based on Section III reactor
pressure vessel rules with the same design factor 3. Because these
Code Cases and Commentaries are now out of print and not available from ASME, he felt it was necessary to publish these documents
in a safe place for future reference and understanding by users of the
ASME Code. His concern is the fact that ASME no longer saves or
archives some technical documents that are not in current use. That
fact makes it difficult for Code users who are trying to understand
the background and technical basis for current Code requirements.
Organization and
Operation of the ASME
Boiler and Pressure Vessel
Code Committees
Thomas P. Pastor, Ralph Hill III, and Richard (Rick) Swayne1
ORGANIZATION AND RESPONSIBILITY
In 1911 the ASME set up a committee for the purpose of formulating standard rules for the construction and fabrication of steam
boilers and other pressure vessels. The committee is now known
as the ASME Boiler and Pressure Vessel (BPV) Committee. From
one section promulgated by one committee of 7 members in 1911,
the Boiler and Pressure Vessel Code (the Code) has grown to thirteen standards committees with a 2016 total membership of over
1500 volunteers in the overall committee structure. Of this total
there are approximately 500 international members.
The organization now consists of the Technical Oversight Management Committee with 30 members, a Boiler and Pressure Vessel Administrative Committee with 12 members. There are thirteen
standards committees whose responsibilities are described below:
t BPV Committee on Power Boilers responsible for Sections I
and VII with 26 voting members.
t BPV Committee on Materials responsible for Section II –
Parts A, B and D with 26 voting members.
t BPV Committee on Construction of Nuclear Facility
Components responsible for Section III – Divisions 1, 2, 3, 4
and 5 with 32 voting members.
t BPV Committee on Heating Boilers responsible for Section
IV and VI with 13 voting members.
t BPV Committee on Nondestructive Examination responsible
for Section V with 20 voting members.
t BPV Committee on Pressure Vessels responsible for Section
VIII – Divisions 1, 2, and 3 with 31 voting members.
1
The initial first edition of this publication this chapter appearing in the
“front matter” was authored by Late Martin D. Berstein and the second and
third editions was updated by Guido G. Karcher. For the fourth edition this
chapter was revised by Joel Fieldstein and Thomas P. Pastor. For this fifth
edition this chapter has been updated by Thomas P. Pastor, Ralph Hill III
and Richard (Rick) Swayne. – Editor
t BPV Committee on Welding, Brazing and Fusing responsible for Section IX and Section II – Part C with 23 voting
members.
t BPV Committee on Fiber-Reinforced Plastic Pressure Vessels
responsible for Section X with 24 voting members.
t BPV Committee on Nuclear Inservice Inspection responsible
for Section XI with 34 voting members.
t BPV Committee on Transport Tanks responsible for Section
XII with 10 voting members.
t BPV Committee on Overpressure Protection responsible for
the development of the future Section XIII with 15 voting
members.
t Committee on Boiler & Pressure Vessel Conformity Assessment responsible for the accreditation programs for associated with Sections I, IV, VIII Divisions – 1, 2 and 3 and X
with 15 voting members.
t Committee on Nuclear Certification responsible for nuclear
certification programs associated with Section III, Divisions –
1, 2, 3 and 5 with 17 voting members.
The membership of the thirteen BPV standards committees is
balanced among various interest categories so that no one interest category can dominate the actions of a committee. The major
interest categories include users, design and construction firms,
regulatory agencies, material manufacturers, fabricators, authorized inspection, and general interest, among others.
There are also a number of sub tier committees that report to the
standards committees. These groups are known as subcommittees,
subgroups, working groups, special working groups, task groups,
project teams and special committees. The total number of groups
within the structure responsible for the development of the Code
currently stands at just over 200.
Recent figures show over 3300 positions are held on all committees. The total number of committee positions is larger than the
total volunteer membership mentioned previously since many individuals serve on more than one committee.
lxii t Organization and Operation of the ASME Boiler and Pressure Vessel Code Committees
There are four other groups that act in an advisory capacity to
the thirteen standards committees. These are called the Conference
Committee, the Marine Conference Group, and the International
Interest Review Group (IIRG) and the ASME Delegate program
described below. These advisory committees represent legal jurisdictions or other authorities that have made the Code a legal
requirement. Each state in the U.S., each province in Canada, and
certain large cities that have adopted one or more sections of the
ASME Code and maintain a department that enforces the Code is
invited to appoint a representative to act on the Conference Committee. There are about 60 such representatives on the Conference
committee. An analogous committee is the Marine Conference
Group, composed of representatives of marine interests that promulgate and enforce regulations based on the ASME Code. All these
advisory functions have direct access to the standards committees,
and can bring to them any problems with respect to implementation of Code requirements. They are all entitled to participate in
discussion at the standards committee and in voting by letter ballot
for items that are receiving first consideration (explained below
under Voting by the standards committees). On items receiving
reconsideration, such advisory Committee members’ participation is limited to discussion, without vote. This participation by
the regulatory authorities fosters their willingness to accept Code
rules in their jurisdictions and assists in uniform administration of
the Code.
The principal objectives of both the International Interest Review Group (IIRG) and the ASME Delegate programs are improved international communications and to reduce the barriers to
participation in ASME standards development activities by people
living outside the U.S. and Canada. A delegate is an individual
appointed to a committee or sub tier group who represents an organization that is outside the U.S. and Canada, and that is recognized within its country. Members of the group could work in their
native language, and designate an English-speaking representative
as a voting member of an ASME codes and standards committee. These groups could be trade organizations such as manufacturers’ associations or user groups, national standards committees,
or organizations responsible for oversight of a particular industry.
Delegates may be appointed to any committee, group, or project
team needed to support the development, update and maintenance
of ASME codes and standards. The IIRG consists of appointed
representatives from any national agency that accepts one or more
Sections of the ASME Boiler and Pressure Vessel Code as a means
of meeting regulatory requirements for which they have responsibility. Not only does participation give national jurisdictional
authorities knowledge of proposed changes to the ASME Code, it
also gives them an opportunity to contribute to the process based
on the needs of their industry and their organization’s responsibility to protect the safety of the public. The balloting and advisory
privileges of a Delegate and the members of the IIRG are essentially identical to the members of the Conference Committee and
the Marine Conference Group.
Many members of ASME and Code users may not have a clear
picture of its overall organizational structure and just how and
where the Boiler and Pressure Vessel committees fit in. In this regard, the top ASME level of authority is the Board of Governors
(BOG). The ASME Council on Standards & Certification reports
directly to the BOG. The ASME Boiler and Pressure Vessel Code
Committee report to the Council on Standards & Certification via
the Board on Pressure Technology Codes and Standards and the
Board on Nuclear Codes & Standards. Major policy and organizational decisions and directions are developed at the Board level
and they also serve as the highest levels for appeals. However the
majority of the technical development and balloting occurs at the
standards committee level.
The personnel of the standards committees, subcommittees,
subgroups, and working groups are listed in the front of all book
sections. The standards committees are made up of a cross section of members from each of the subcommittees, subgroups and
working groups that report to it. Usually the chair and vice chair
of the subordinate groups will be members of the standards committee as well as some other senior members of the sub tier committees. This arrangement of overlapping membership facilitates
the work of the standards committees, because certain members of
the standards committees are quite familiar with items originating
in their respective sub tier committees, and can thus explain and
answer questions about the items when the standards committees
considers them.
A BALANCE OF INTERESTS
Since its inception in 1911 when the Boiler and Pressure Vessel
Committee was established, it has been ASME policy that members should represent a balance of interests to avoid domination by
any one interest group. This is one of the ways by which the ASME
tries to ensure that actions of a standards committee represent a
valid technical consensus, fair to all and free of any commercial
bias. Above all, the goal is to promote the welfare and safety of
the public. In furtherance of this goal, each committee member
must sign an agreement to adhere to the ASME policy on avoidance of conflict of interest and to conform to the ASME Code of
Ethics. The ASME has also established procedures to provide for
due process in committee operations (e.g., hearings and appeals),
thus safeguarding the members and the ASME against any charges
of unfairness.
Members of a standards committee are categorized according to
the interests they represent. ASME has designated 25 categories of
interest involved in BPV codes and standards activities. Seventeen
of these categories are represented on the thirteen Boiler and Pressure Vessel Standard Committees:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
Constructor
Design/Engineering Organization
Designer/Constructor
General Interest, such as educators
Insurance/Inspection
Laboratories
Manufacturer
Material Manufacturer
Owner
Oil Refining/Production
Regulatory, e.g., representatives of local, state, or federal
jurisdictions
Consultant
User, i.e., a user/owner of the products to which the Code
applies
Utility, e.g., power plant user/operator
Wrought Boiler Manufacturer
Cast Boiler Manufacturer
Water Heater Manufacturer
Pressure relief Device Manufacturer
Individuals typically become members of a Boiler and Pressure
Vessel standards committee by attending committee meetings as
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t lxiii
guests (meetings are open to the public), by indicating their desire
to join, by participating in discussions, and assisting in the technical activities of the committee. There is a practical limit to the size
of these various active committees, and as openings arise, the chair
chooses members to maintain a balance of interests on the committees and, also, seeks out individuals with particular expertise. New
members usually start by joining a subgroup or working group, and
as they gain experience in committee operations and demonstrate
their ability by contributing their own expertise, they eventually
move up within the committee organization. Prospective members
should be aware that they need employer or personal support for
committee participation, to cover the travel and time expenses required to participate and attend meetings.
In addition to the many volunteer members of the committee, who are supported in these activities by their companies, the
ASME maintains a staff of directors and secretaries who facilitate
the work of the committees by managing meeting arrangements,
preparation of meeting agenda and minutes, arrangements for publication of the Code, scheduling, record keeping, correspondence,
and telephone inquiries from the public. Staff secretaries prepare
the agenda and take minutes at the standards committee level. At
the subcommittee, subgroup, and working group levels, one of the
volunteer members of the committee usually serves as secretary.
standards committee and book titled, “Rules for Overpressure Protection,” which will become Section XIII. The plan is for the BPV
construction codes to remove the technical rules covering overpressure protection and to directly reference these requirements
from Section XIII. It is expected that Section XIII will be approved
and published in time for the 2019 Edition, and shortly thereafter
each BPV construction code committee will begin taking action to
remove the technical rules related to overpressure protection from
their books and directly reference Section XIII. The Section XIII
standards committee will report to the Board on Pressure Technology Codes and Standards.
Until 1989, a service committee known as the Subcommittee on
Properties of Metals (SC-P) established the allowable stresses for
all the materials used throughout the Code. In 1989, this committee
was merged with Subcommittee on Material Specifications (SC II)
into a new committee called the standards committee on Materials
(SC II), which carries out all the duties formerly handled by the
two separate committees.
The reference Sections are also used by other pressure equipment Codes and Standards, such as the B31 Piping Code, B16
Components Standards and Bioprocessing Equipment Code.
THE ACCREDITATION COMMITTEES
THE CODE SECTIONS AND THEIR RELATED
STANDARD COMMITTEES
The formulation of “standard rules for the construction of steam
boilers and other pressure vessels” on which the committee started
in 1911 eventually became the first edition of Section I of the
ASME Boiler and Pressure Vessel Code, in 1915. That first edition actually dealt only with boilers. Section VIII, covering pressure vessels for other than steam, was added later, in 1925, as part
of the expanding coverage of the Code. (Section VIII now covers
all kinds of vessels, including those containing steam.) There are
now thirteen sections of the Code, designated by Roman Numerals
I through XIII. Section XIII is under development and provides
rules for the construction and installation of pressure relief devices.
The thirteen Sections of the Code can be divided into two basic
categories, which are “product Sections” (i.e., components are
constructed to the rules), and “reference Sections” (i.e., the rules
are used via reference by the product Sections) as shown in Table
1. The various sections of the ASME Code (sometimes called the
book sections) and the committees directly responsible for each are
shown in Table 1.
THE SERVICE COMMITTEES
In addition to the thirteen Standard Committees governing the
various book sections, there is one service committee under the
Technical Oversight Management Committee, called a service
committee because it serves the book sections.
The Subcommittee on Safety Valve Requirements (SC-SVR)
deals with the design, construction, testing, and certification of
the pressure relief devices. Currently rules for overpressure protection are published in each of the construction codes, and the
SC-SVR provides technical support to the different construction
codes when there is a need to update these rules. In July 2016, the
Board on Pressure Technology Codes and Standards and the Council on Standards and Certification approved the creation of a new
As explained in the discussion of the various Code symbol
stamps in section 1.7.8.3, no organization may do Code work without first receiving from the ASME a Certificate of Authorization
to use one of the Code symbol stamps. The accreditation committees issue these certificates to applicants found to be qualified by
ASME review teams and by the volunteer accreditation committees. The Committee on Boiler & Pressure Vessel Conformity
Assessment (CBPVCA) handles this work for boiler and pressure
vessel activities. The Committee on Nuclear Certification (CNC)
does the same for nuclear activities. Any disagreements as to the
qualifications of applicants and any allegations of Code violations
are dealt with by one or the other of these two accreditation committees, in deliberations that are not open to the general public.
An ASME Certificate of Authorization can be revoked by cause,
following hearing and appeal procedures.
In February 2009, the ASME Board on Conformity Assessment
(BCA) formed the Committee on Conformity Assessment Requirements. The mission of this Committee was to develop a separate
standard that includes the necessary ASME conformity assessment
requirements currently contained in various ASME Codes and
Standards. The first edition Conformity Assessment Requirements
(ASME CA-1) was published in 2013. The current version of CA1-2014 contains conformity assessment requirements for all of
the ASME BPV nonnuclear sections, as well as the Bioprocessing Equipment Standards (BPE) and Reinforced Thermoset Plastic
Corrosion Resistant Equipment standards (RTP). Future editions
of CA-1 will include coverage for the nuclear construction codes.
Coincident with this activity, each of the BPV construction codes,
as well as BPE and RTP, have taken action to remove the conformity assessment requirements from their individual standards and
replace them with a direct reference to CA-1.
COMMITTEE OPERATIONS
Since 1986, the Boiler and Pressure Vessel Code Committees
have had four major meetings a year, during four weeks known
lxiv t Organization and Operation of the ASME Boiler and Pressure Vessel Code Committees
TABLE 1 THE BOOK SECTIONS MAKING UP THE ASME B&PV CODE
Code Section
Governing Committee
Section I, P
Rules for the Construction of Power Boilers
Standard Committee on Power Boilers (BPV I)
Section II, R
Materials
Standard Committee on Materials (BPV II)
Section III, P
Rules for the Construction of Nuclear Facility Components
Standard Committee on Construction of Nuclear
Facility Components (BPV III)
Section IV, P
Heating Boilers
Standard Committee on Heating Boilers (BPV IV)
Section V, R
Nondestructive Examination
Standard Committee on Nondestructive Examination
(BPV V)
Section VI, R
Recommended Rules for the Care and Operation
of Heating Boilers
Subgroup on Care and Operation of Heating Boilers
(of BPV IV)
Section VII, R
Recommended Guidelines for the Care of Power
Boilers
Subgroup General Requirements (of BPV I)
Section VIII, P
Rules for the Construction of Pressure Vessels
Standard Committee on Pressure Vessels (BPV VIII)
Section IX, R
Welding and Brazing Qualifications
Standards Committee on Welding and Brazing
(BPV IX)
Section X, P
Fiber-Reinforced Plastic Pressure Vessels
Standard Committee on Fiber-Reinforced Plastic
Pressure Vessels (BPV X)
Section XI, P
Rules for Inservice Inspection of Nuclear Power
Plant Components
Standard Committee on Nuclear Inservice Inspection
(BPV XI)
Section XII, P
Rules for the Construction of and Continued Service
of Transport Tanks
Standard Committee on Transport Tanks (BPV XII)
Section XIII, R
Rules for Overpressure Protection
Standard Committee on Overpressure Protection
(BPV XIII)
* P denotes a product Code
* R denotes a reference Code
as Code weeks. The committees used to meet six times a year,
but decided to reduce the number of meetings as an economy
measure. The four meetings are scheduled to result in approximately equal time intervals between meetings (i.e., February,
May, August and November). The May meeting is held jointly
with the annual meeting of the National Board of Boiler and
Pressure Vessel Inspectors. The chief inspectors of the various
states and provinces of Canada who comprise the membership
of the National Board are the top officials who enforce those
sections of the Code that are adopted into the laws of their jurisdictions. This meeting also provides an opportunity for them to
observe and participate as guests or conference committee members at the various Code committee meetings. The Technical
Oversight Management Committee always meets on Friday; the
Standard Committees meet earlier in the week. Section II, IX,
XII and the Accreditation Committees meet on Tuesday, Section IV on Wednesday, and Sections I, III, VIII, and XI meet on
Thursdays of a Code week. Subgroups and working groups usually meet earlier in the week than their parent Standard Committees. This arrangement facilitates an orderly and timely flow of
information from the sub tier committees upward to the Standard
Committees.
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t lxv
HOW THE COMMITTEE DOES ITS WORK
The thirteen Boiler and Pressure Vessel Standard Committees
administer the Code. The major technical work of the committees
falls into four categories; providing interpretations of the Code in
response to inquiries, developing Code Cases, revising the Code,
and adding new provisions to it. This work usually starts at the
sub tier levels of the committee structure (i.e., the subgroups and
working groups). Many items (Code changes for instance) require
consideration by the standards committee. Actions of the standards
committee are subject to procedural approval by one or the other of
the two Boards above the standards committee (one for nuclear and
the other for non-nuclear items). All proposed, revised, or withdrawn standards are announced on the ASME Web site for public
review. A notification is also included in Mechanical Engineering
that, at a minimum, directs interested parties to the ASME Web
site for public review announcements, and provides instructions on
obtaining hard copies of the public review proposals. Because all
proposed Code revisions also require ANSI approval, they are also
announced in ANSI Standards Action.
These approval actions by the Supervisory Boards as well as
the public review are conducted concurrently with the standards
committee voting following the respective standards committee
meetings. Thus these items have received very careful technical
consideration within the Committee and are also open to review
by the public to avoid any inequity, hardship, or other problem that
might result from a Committee action. Any comments received
during public review delay an item until the originating committee
considers those comments. The several categories of the committee work are now described.
CODE INQUIRES AND INTERPRETATIONS
Anyone who has used the Code knows the aptness of the second
paragraph of the preamble to Section I and similar statements in Sections IV and VIII, Div. 1 & Div. 2: “The Code does not contain rules
to cover all details of design and construction.” What it contains
rather are many rules for what might be called standard construction
covering most typical and common construction details. This has
evolved over the past 90 plus years as modern boiler and pressure
vessel construction have evolved, presenting new situations, new
arrangements, and new equipment. It is thus not surprising that so
many inquiries are received by the standards committees, asking for
guidance in the application of specific provisions of the Code.
The ASME has established procedures and controls on responding
to inquiries and publishes the questions and replies for the guidance
of all users of the Code. These procedures are intended to protect the
committee members and the ASME from any inference that a specific industry or company has an undue influence in the formulation
of the questions or replies, or may benefit to the detriment of others.
Sometimes inquirers ask questions that the standards committees
can’t answer, for various reasons. The standards committees are not
in the business of consulting engineering. They do not have the resources to study plans and details sent in by inquirers and pass judgment on those designs. They are also in no position to undertake
the potential liability for making such judgments. Accordingly, the
ASME Secretaries use one of four form letters for responding to the
most common types of questions considered inappropriate: Indefinite questions that don’t address some particular Code requirement;
semi-commercial questions; questions that would involve review or
approval of a specific design; and questions that ask for the basis or
rationale of Code rules. These form letters explain that the standard
committee cannot or does not answer such questions and advises
the inquirer to pose only questions that pertain to existing wording
and addressing particular Code requirements, or to make specific
recommendations for any proposed Code changes with supporting
technical reasons or data. The standards committees also issue “intent interpretations,” as described below.
In 1983, to reduce the work involved in replying to inquiries,
mandatory appendices that give instructions on how to prepare
technical inquiries were added to the various book sections. (See,
for example, Appendix I of Section I). Today, Code users seeking
an interpretation of a particular Code paragraph can submit their
request via ASME’s online tool at: https://cstools.asme.org/Interpretation/InterpretationForm.cfm. Once submitted, the request is
assigned a tracking number, after which the Secretary of the standards committee usually reviews the files of previous inquiries to see
if the same question or a similar one has previously been answered.
If such a reply is found, it is sent to the new inquirer. If not, there
are three ways to handle an interpretation of an inquiry as follows:
t Standards Committee: Interpretations are approved by a vote
of the standards committee. No member interest category
shall have a majority on the committee.
t Special Committee: Interpretations may be approved by the
unanimous vote of a special committee. Members of the special committee shall be members of the consensus committee
responsible for the standard or subordinate group responsible
for the standard. No member interest category shall have a
majority on the special committee. The special committee
shall have at least five members, one of which shall be the
ASME staff secretary responsible for the subject standard.
Special committee members shall be appointed by the Chair
of the standards committee.
t Intent Interpretations: The basic objective of an interpretation
is to clarify words or requirements that exist in the Code.
However in some cases technical inquiries that cannot be
answered on the basis of existing wording of the pertinent
standard may be answered by an “intent” interpretation.
Intent interpretations can answer questions about subjects that
address industry construction practices not specifically covered in the Code or clarify conflicting or incorrect wording.
An intent interpretation shall be submitted to the standards
committee for approval along with a proposed revision(s) to
the standard that supports the intent interpretation. Both the
intent interpretation and the revision(s) to the standard must
be approved for the interpretation to be issued.
ASME staff may also offer informal responses to inquiries, as
a means of providing guidance. Such individual responses are not
published and are accompanied by a statement making it clear that
they are the opinion of the individual, and not an official interpretation. These responses may be either verbal or written. If written,
the response shall not be on ASME interpretation letterhead. After approval, all inquiries and replies are published, in an on-line
database. The database can be accessed at https://cstools.asme.org/
Interpretation/SearchInterpretation.cfm.
ADDITIONS AND REVISIONS OF THE CODE
The Code is subject to continuous change – some provisions are
revised, others deleted, still others added. Although some changes
lxvi t Organization and Operation of the ASME Boiler and Pressure Vessel Code Committees
originate high in the committee structure (e.g., the mandatory appendices in each book section on preparation of technical inquiries), most start at the subtier level, in response to an inquirer’s
request for a change or a request by members of the standards
committee to clarify, update, or expand existing Code provisions.
The development of a Code change follows a path similar to that
of a technical inquiry. Depending on the nature of the work, the
cognizant subtier chair assigns either a Project Manager or a task
group to do the work. In appointing the task group, the chair tries
to maintain a balance of interests while making sure to include
members with the specific expertise appropriate for the task. If and
when the subgroup approves the change proposed by the Project
Manager or task group, the proposal is forwarded to the standards
committee for consideration, with documentation giving the background of the proposed change.
At this stage consideration of the proposed revision is handled a
couple of different ways by the BPV Standard Committees. Some
Standard Committees (e.g., BPV I, BPV IV, and BPV XI) will review a proposal during their open meeting prior to placing the item
onto a ballot for a formal vote. This gives the Standards Committee
members an opportunity to hear from the Project Manager or Task
Group concerning the background for the change, and gives members the opportunity to ask questions, and in many cases offer both
editorial and technical improvements to the item prior to placing it
on the standards committee first consideration ballot.
For other standards committees, such as BPV VIII, proposals
for revision from subtier committees are immediately placed on
first consideration ballot by the standards committee, Conference
Committee and Supervisory Board. The reason BPV-VIII handles
their work in this manner is that the volume of proposals generated
by subtier committees each meeting is so large that it would not be
possible to consider presentations on all these items in a one-day
meeting during Code week. By having all of the proposals initially
submitted directly to a ballot, many of the simpler items are approved, and only those items that receive one or more negatives or
significant technical comments are held over to the next meeting
of the standards committee for consideration and/or resolution of
the negatives. Although all of the BPV standards committees operate according to a common set of ANSI-accredited procedures,
there is enough flexibility within these procedures to allow each
committee to manage their workload in a manner that assures a
high quality technical review as well as efficient use of available
resources.
In preparing an item for consideration by the standards committee, the Project Manager writes a paragraph of background explanation that accompanies each item on the standards committee
letter ballot, in what is called “an action box” for the item. This
explanation may include other technical information supporting
the proposed action, such as a paper from an ASME conference
describing a new or improved design method. This explanation is
very helpful, because the first time a standards committee member
sees an item that hasn’t come from his own subtier committee is
when it appears on the standards committee letter ballot.
Code Cases are issued to clarify the intent of existing requirements or provide, when the need is urgent, rules for materials or
constructions not covered by existing Code rules, or alternatives to
the existing requirements. It is a common practice to issue a Code
Case for new or enhanced materials, testing practices, or design
methods, and then after a trial period, the Code Case requirements
are incorporated into the Code book requirements and the Code
Case is annulled. Code Cases and their use are explained in more
detail in section 1.3.3 of Chapter 1 of this volume.
ASME WEB SITE TOOLS AND “CODES &
STANDARDS CONNECT”
In 2001 ASME started an intensive program to use the Internet
for managing and coordinating C&S activities and balloting. This
started very basically with what was called the WBPMS (WebBased Project Management System). The WBPMS began by supporting standards committee balloting and has since grown into a
major tool in the development, coordinating and balloting of C&S
actions. In September 2004 the WBPMS was changed to “Codes &
Standards Connect” (C&S Connect) and is an electronic tool used
by both Staff and Volunteers to process many committee functions.
C&S Connect is currently made up of 13 sections or Tabs, six of
which form the backbone of this system.
1. My Committee Page Tab – Enables access to standards committee and any subtier group pages. Future meeting dates,
minutes, agendas, rosters, etc. can be retrieved from this.
The charter of the committee and the contact information
of the secretary (ASME staff member) and other interesting
information are posted on this page.
2. My Items Tab – the “My Items” tab lists all records for which
the logged-in member is the Project Manager, either Technical or Administrative. Updates can be performed except
when the item is out for ballot. Responses can be posted
through this page to comments or negatives during the
ballot.
3. Ballots Tab – the “Ballots” tab lists all open ballots for the
logged in member. This would include ballots for approval
and also review and comment. Closed ballots may be accessed through the Search Tab.
4. Search Tab – The “Search” tab is used to locate records, ballots and cases by their number or by other criteria such as
keyword, project manager name, level, committee, Standard, etc.
5. VCC Tab – The Volunteer Contact Center (VCC) tab provides a method for sending e-mails to other volunteers,
committees, or a stored distribution list. So long as volunteers accurately maintained their profiles, including their
current e-mail address, the VCC provides the most efficient, direct method for sending e-mails concerning committee business.
6. AS-11 Tab – The AS-11 tab allows a volunteer to query the
ASME membership database and locate contact information and committee assignments for all volunteers and
ASME staff.
The C&S Connect has greatly streamlined the standard development process and allows hundreds of volunteers to more efficiently
carry out the work of updating and maintaining the different
ASME standards. Only Codes & Standards members have access
to C&S Connect which can be reached at: https://cstools.asme.org/
csconnect.
VOTING BY THE STANDARDS COMMITTEE
The standards committee letter ballot contains all items approved by the sub tier committees that require further approval
by the standards committee. This letter ballot is also distributed to
the Conference Committee and the Technical Oversight Management Committee (TOMC) for technical review and comment. The
boiler and pressure vessel items are sent to the Board on Pressure
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t lxvii
Technology Codes and Standards (BPTCS) and the nuclear items
are sent to the Board on Nuclear Codes and Standards (BNCS) for
technical comment. Typical B&PV standards committee ballots
are open for thirty days.
All voting on ballots is carried out electronically on C&S Connect, including those committees that are included in the ballot for
Review and Comment. Members, who register a disapproved vote,
must support their negative in writing. The Project Manager for an
item must respond to any comments or negative votes within the
C&S Connect record.
At the close of the letter ballot, the C&S Connect system automatically generates a tally of the vote, and determines whether or
not the item is approved based on the voting procedures adopted
by the particular standards committee. Items that are not approved
during this first consideration ballot are carried over for consideration at the next meeting of the standards committee.
Items coming before the standards committee are considered
within two categories: first consideration and reconsideration, usually called second consideration. A new item appearing for the first
time on a letter ballot is given “first consideration” by the Committee. Items that did not receive negatives from members of the
standards committee or objections from the advisory committees,
BPTCS, and BNCS are reported as “approved” at the standards
committee meeting and require no further action. A single negative
vote is sufficient to stop a first consideration item and return it to
the originating sub tier committee for reconsideration. Technical
objections from the advisory committees, BPTCS, and BNCS are
treated like negative votes received from members of the standards
committee, and responses must be provided to those objections.
When a negatively voted item is returned to a sub tier committee,
several different actions may be taken. The item may be held in
abeyance for the time being, with no action taken at the sub tier
committee level, pending further work.
Another possibility is that the sub tier committee is not persuaded
by the reasons given by the negative voter, and, at its meeting during the Code week following the letter ballot, the sub tier committee responds to that effect, perhaps with rebuttal arguments, and
reaffirms its earlier action. In that case the item proceeds to the
standards committee meeting, where it is then given what is considered “second consideration” (because this is the second time the
standards committee has seen the item). During second consideration, four negative ballots are required to stop and, in effect, “kill
the item.” If the originating sub tier committee wants to pursue the
matter further, it may start all over, usually by making sufficient
revision to satisfy the objections raised. A subsequent appearance
of the item might be a new first consideration. On the other hand,
if on second consideration an item receives less than four negative
votes, it is considered approved by the standards committee, and it
proceeds to the next two approval levels, the BPTCS for boiler and
pressure vessel items, and the BNCS for nuclear items, and public
review. At this stage, the only basis for a negative vote at the Board
is an assertion that proper procedures had not been followed by the
lower committees.
Most of the items considered by the standards committees are
proposed changes in the various book sections of the Code. Fairly
regularly, some items fail to pass because of strong objections by
other standards committee members who perceive the change as
having negative consequences to safety or representing an unworkable situation when applied to other comparable circumstances.
This is part of the give-and-take of committee actions, which are
intended to achieve a technical consensus of the membership, but
with concern for safety always being paramount.
DUE PROCESS
Persons who consider themselves injured by an action of the
Committee regarding a technical revision, response to an inquiry,
or the refusal to issue a certificate of authorization, can request
a hearing to present their side of the story. Such hearings start at
the standards committee that originated the item. If the standards
committee can’t reach a mutually acceptable solution, the appeal
may be submitted to the appropriate supervisory board and, if necessary, to the Board on Hearings and Appeals of the Council on
Standards and Certification. This careful attention to due process
is the result of an unfortunate event that happened in 1971, the
infamous Hydrolevel Corporation case. Here is the essence of that
case.
Section IV stipulates that boilers must have an automatic lowwater fuel cutoff that stops the fuel supply when the surface of
the water falls to the lowest visible part of the water gage glass.
Hydrolevel had developed a new probe-type low-water fuel cutoff that relied on an electrode on the probe. Water covering the
electrode completed a circuit that maintained fuel flow. When the
water level fell below the electrode and uncovered it, the circuit
was broken and the fuel was stopped.
At that time, another manufacturer dominated the low-water fuel
cutoff market with a float-operated device. That rival manufacturer
happened to have a representative serving as vice-chair of the Section IV committee. Court records subsequently showed that three
officers of the rival manufacturer, including that vice-chair, met
with the chair of the committee to draft an inquiry to the committee. The inquiry asked whether a low-water cutoff with a timedelay feature met the Code. The Section IV chair at that time had
the authority to respond to the inquiry on the ASME’s behalf without the endorsement of the full committee. His letter of response
implied that the device did not meet Section IV requirements and
would not provide adequate safety. Hydrolevel subsequently alleged that the inquiry was deliberately intended to put the probetype of device in a bad light, and that copies of the ASME response
were used by the rival manufacturer’s sales force to discredit Hydrolevel’s device. When a former Hydrolevel customer reported
this to Hydrolevel in 1972, Hydrolevel complained to the ASME
and asked for a clarification of the ruling. This time the ruling was
put before the entire Section IV subcommittee (the vice president
of the rival manufacturer had by this time become chair of the committee), where it was reaffirmed, perhaps because of the committee’s belief that the Code required the fuel to be cut off as soon as
the water level was no longer visible in the water gage glass (and
not after a time delay). However, the standards committee reversed
the ruling and issued an official communication to Hydrolevel saying that the Section IV paragraph in question did not prohibit the
use of low-water cutoff with a time delay.
In 1975 Hydrolevel sued the parties, including the ASME, alleging conspiracy in restraint of trade. The other parties settled, but
the ASME contested the charge, in the understandable belief that
it had done no wrong. A district court judge awarded Hydrolevel
$7.5 million in damages. The ASME appealed, lost that appeal,
and then appealed to the U.S. Supreme Court, which affirmed the
appellate court’s decision. The essence of the court’s finding was
that the ASME had put certain committee members in positions
where they appeared to represent the ASME and had thereby conferred on those agents the ASME’s so-called apparent authority.
Even though the ASME is a nonprofit professional organization,
it was found liable for the willful, anticompetitive, wrongful conduct of its agents. With interest on the triple damages called for by
lxviii t Organization and Operation of the ASME Boiler and Pressure Vessel Code Committees
the antitrust act, ASME had to pay almost 10 million dollars (in
addition, of course, to legal fees). This was a heavy price for an
educational nonprofit organization that gets much of its financial
support from the dues of its members. In an ironic twist of fate, the
principal owner of Hydrolevel died of a heart attack shortly after
hearing the news of the Supreme Court decision.
Following that decision, the ASME developed improved procedures in an attempt to ensure the fairness of interpretations and to
provide for hearings and appeals for anyone who considers himself
injured by an action of the Code committee, such as an Interpretation or a proposed Code change. These procedures should prevent
any further cases like the Hydrolevel case.
tion of applicable code, standard or committee. Within the Boiler
and Pressure Vessel organization, requests for research projects
are submitted to the Technical Oversight Management Committee (TOMC) where a Subgroup on R&D evaluates the project requests and makes a recommendation to the TOMC. Requests for
nuclear research projects are submitted to the Board on Nuclear
Codes and Standards.
ASME ST-LLC publishes project deliverables as Standards
Technology Publications (STPs), which are available through the
ASME Catalog and Digital Store. (https://www.asme.org/shop/
standards#des=STP).
RESEARCH PROJECTS FOR THE
MAINTENANCE AND DEVELOPMENT
OF CODES AND STANDARDS
REALIGNMENT ACTIVITIES OF THE ASME
BOILER AND PRESSURE VESSEL CODE
COMMITTEE STRUCTURE
ASME formed the Codes and Standards Technology Institute
(CSTI) in November 2001 to ensure that ASME codes and standards committees are provided with a continuing source of research
in the technologies that they cover. In August 2004 the ASME
Standards Technology, LLC (ASME ST-LLC) was formed, replacing CSTI. ASME ST-LLC is a not-for-profit Limited Liability
Company with ASME as the sole member, formed to carry out
work related to newly commercialized technology. The ASME STLLC mission includes meeting the needs of industry and government by providing new standards-related products and services,
which advance the application of emerging and newly commercialized science and technology and providing the research and
technology development needed to establish and maintain the technical relevance of codes and standards. Visit www.stllc.asme.org
for more information.
Historically, ASME has periodically identified needs for specific research projects to support the codes and standards development process. This research was previously performed by outside
organizations with ASME support. ASME ST-LLC has helped enhanced the coordination and long range planning and management
of codes and standards development activities while strengthening
volunteer participation in developing the technology for codes and
standards.
ASME’s approach to standards development for emerging
technologies recognizes the important role of technically relevant
standards in advancing the commercialization, enhancing consumer
confidence, and protecting public health and safety. ASME ST-LLC
research and development (R&D) projects strive to bridge the gaps
between technology advancement and standards development.
ASME’s involvement in R&D projects helps produce results that
respond to the needs of voluntary consensus committees in developing technically relevant codes and standards. ASME identifies
and prioritizes R&D needs to help focus the use of limited resources
in these priority areas. Collaboration in R&D projects helps to minimize individual investment while maximizing benefits.
As of early 2011, ASME ST-LLC was managing over 40 separate development projects. Some examples of ASME ST-LLC
projects include the rewrite of ASME Pressure Vessel Code, Section VIII, Division 2, hydrogen infrastructure standards development, high temperature materials for Generation IV reactors,
probabilistic risk assessment (PRA) training development, and
fusion magnet code development. Projects can be initiated by
anyone, but require a clear scope definition, a legitimate business
need, establishment of any funding requirements, and identifica-
In February 2007 the BNCS and BPTCS approved motions to
move forward with the concept of realigning the ten BPV subcommittees and the one B&PV standards committee that they reported
to. The need for such realignment was based on the observations
that the organization was strained, considering the current climate
and projected future workloads in both the nuclear and non-nuclear
areas and the need to prepare for the future. Considering this the
following Code and Standards vision and mission statements were
developed for guidance:
Vision: ASME aims to be the essential resource for mechanical
engineers and other technical professionals throughout the world
for solutions that benefit humankind.
Mission: ASME’s mission is to serve diverse global communities by advancing, disseminating and applying engineering knowledge for improving the quality of life; and communicating the
excitement of engineering.
In addition to these global guidance statements the following
specific categories were also addressed:
t Volunteer work loads
t Responsiveness to Industry-Specific Needs
t Global Acceptance
t Integrity/Credibility of Standards
t Turnaround/Cycle Time
t Volunteer Recruitment and Retention
Using the above as metrics a facilitated workshop meeting
was held in January 2008 with the participation of a broad crosssection of Volunteer, Regulatory, ASME Staff and International
participation. The outcome of that workshop and subsequent deliberations by the BPTCS, BNCS, and Council Standards & Certification resulted in the formulation of a plan that would transition
the ten BPV Subcommittees that promulgated rules in the ASME
BPV Code book sections into separate standards committees each
reporting to their respective Boards (BPTCS or BNCS). Between
the ten new standards committees and the Boards would be a new
Technical Oversight Management Committee (see Figure X). This
new committee would be responsible for:
(1) Overseeing technical adequacy and consistency across the
BPV standards committees,
(2) Provide advice and recommendations to the Boards on strategic issues and R&D initiatives,
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t lxix
BCA
BNCS
BPTCS
Technical Oversight
Management
CNC
Joint Project Teams
CBPVCA
BPTCS
Safety Valve
Requirements
Service Related
FIG. X
BOILER AND PRESSURE VESSEL ORGANIZATION
(3) Supervise subordinate groups responsible for specialized
areas or activity (e.g., Safety Valve requirements),
(4) Maintain the Foreword which was common to all the Book
Sections.
Shortly after the realignment plan was approved a Task Group
was established to implement the proposed changes with a target
date of February 2009 (the first meeting date for consideration
of changes to the next Edition of the Boiler and Pressure Vessel
Code). The time was needed for development and approval of
charters for each of the new standards committees and TOMC, to
assure that the committees met the required interest-balance of its
membership and, most importantly, each new standards committee
member understood their voting responsibility as a member of a
standards committee.
The realignment of the Boiler and Pressure Vessel Committee
was introduced in February 2009 and has been operating successfully since then. It is felt that this realigned organization structure
has met the objectives above while continuing to assure safe pressure containing structures via ASME C&S and ANSI consensus
requirements for Codes and Standards. In addition, technical interchanges and liaisons between the nuclear and non-nuclear Codes
and regulatory organizations (e.g., NRC, National Board, Jurisdictions, etc.) have continued without disruption.
CHAPTER
1
Introduction to Power Boilers
John R. MacKay, Ed Ortman and Jay Vattappilly1
1.1
INTRODUCTION
Power Boilers, Section I of the ASME Boiler and Pressure Vessel Code [1], provides rules for the construction of power boilers,
but since it is neither a textbook nor a design handbook, its rules
are accompanied by very little explanation. The objective of this
chapter is to provide an overview of Section I rules, their intent,
and how they are applied and enforced.
This chapter is an abbreviated version of the book Power Boilers, A Guide to Section I of the ASME Boiler and Pressure Vessel
Code [2]. That comprehensive guide formed the basis for a twoday ASME Professional Development course on Section I, developed and taught by Martin D. Bernstein and Lloyd W. Yoder. The
Second Edition [3] of the book, revised by John R. MacKay and
James T. Pillow, was published in May 2011. The ASME Professional Development course on Section I (PD665—BPV Code,
Section I: Power Boilers) is still offered by ASME. The course
outline and registration for this week long course can be accessed
on the ASME website (www.asme.org).
Some of the more important aspects of ASME Section I construction are covered here, these are:
t History and Philosophy of Section I
t How the ASME Code Works (the System of ASME Code
Construction)
t Organization of Section I
t Scope of Section I
t Distinction between Boiler Proper Piping and Boiler External
Piping
t How and Where Section I Is Enforced
t Fundamentals of Section I Construction:
t Permitted Materials
t Design
t Fabrication
t Welding and Postweld Heat Treatment
t Nondestructive Examination
t Hydrostatic Testing
t Third-Party Inspection
t Certification by Stamping & Data Reports
The design and construction of power boilers involves the use
of other sections of the ASME Code besides Section I, and the
1
Late Martin D. Bernstein was the originator of this chapter for the 1st
edition. Lloyd W. Yoder updated this chapter for the second edition and
John R. MacKay updated for both the third and fourth editions.
use of those other book sections is mentioned in this chapter when
appropriate. Section II, Materials [4], provides detailed specifications for materials and welding consumables, as well as tabulations of allowable stresses and material properties, such as yield
strength and tensile strength as a function of temperature. Section
V, Non-destructive Examination [5], contains a series of standards
that provide the methodology for conducting the various nondestructive examinations used in Section I construction. Section
IX, Qualification Standard for Welding, Brazing, and Fusing Procedures; Welders; Brazers; and Welding, Brazing, and Fusing Operators [6], provides the information necessary to qualify the weld
procedures and the welders required for Section I construction. In a
rather unusual arrangement, the construction rules for boiler piping
are found partly in Section I and partly in the B31.1 Power Piping Code [7]. This has led to considerable misunderstanding and
confusion, as explained in section 1.5 of this chapter, Distinction
Between Boiler Proper Piping and Boiler External Piping. For a
fuller description of those other code sections refer to the specific
chapters in this volume that cover them.
Those unfamiliar with the ASME Code may be confused at
first by a number of terms in it. Examples include Manufacturer,
third-party inspection, Authorized Inspector (AI), Authorized Inspection Agency, jurisdiction, Maximum Allowable Working Pressure (MAWP), boiler proper, boiler external piping, interpretation,
Code Case, accreditation, Manufacturer’s Data Report, and Certificate of Authorization (to use the Certification Mark). These terms
are explained in the text wherever appropriate.
Although the ASME Boiler and Pressure Vessel Code changes
very slowly, it does change continuously. The rate of change in
recent years seems to have increased, perhaps due to technological innovation and international competition. Thus, although this
chapter provides a substantial body of information and explanation
of the rules as they now exist, it can never provide the last word.
Nevertheless, it should provide the user with a very useful introduction and guide to Section I and its application.
1.2
HISTORY AND PHILOSOPHY
OF SECTION I
It is helpful to begin the study of Section I of the ASME Boiler
and Pressure Vessel Code with some discussion of its character and
philosophy. According to the dictionary, the term code has several
meanings: a system of principles or rules; a body of laws arranged
systematically for easy reference; a systematic statement of a body
of law, especially one given statutory force. Section I is primarily a system of rules. When the ASME decided in 1911 that the
1-2 t Chapter 1
country needed a boiler code, it assigned a committee and gave it a
mandate to formulate standard rules for the construction of steam
boilers and other pressure vessels. The first edition of what is now
known as Section I was finally approved by the ASME in 1915,
and incorporated what was considered at the time to be the best
practice in boiler construction. However, the guiding principle,
then as now, was that these are safety rules.
Part of the foreword of Section I explains the guiding principles
and philosophy of Section I, and also of the Boiler and Pressure
Vessel Committee (the Committee), which continues to administer
the Code. As done in the Foreword, where this chapter refers to
“the Committee,” each of the committees listed in the Foreword
are included individually and collectively. Here are some excerpts
from the Foreword from the 2015 Edition:
In 1911, The American Society of Mechanical Engineers established the Boiler and Pressure Vessel Committee to formulate
standard rules for the construction of steam boilers and other pressure vessels. In 2009, the Boiler and Pressure Vessel Committee
was superseded by the following committees:
(a) Committee on Power Boilers (I)
(b) Committee on Materials (II)
(c) Committee on Construction of Nuclear Facility Components (III)
(d) Committee on Heating Boilers (IV)
(e) Committee on Nondestructive Examination (V)
(f) Committee on Pressure Vessels (VIII)
(g) Committee on Welding, Brazing, and Fusing (IX)
(h) Committee on Fiber-Reinforced Plastic Pressure Vessels (X)
(i) Committee on Nuclear Inservice Inspection (XI)
(j) Committee on Transport Tanks (XII)
(k) Technical Oversight Management Committee (TOMC)
Where reference is made to “the Committee” in this foreword,
each of these committees is included individually and collectively.
The Committee’s function is to establish rules of safety relating only to pressure integrity, which govern the construction2 of
boilers, pressure vessels, transport tanks, and nuclear components,
and the inservice inspection of nuclear components and transport
tanks. The Committee also interprets these rules when questions
arise regarding their intent. The technical consistency of the Sections of the code and coordination of standards development activities of the Committees is supported and guided by the Technical
Oversight Management Committee. This code does not address
other safety issues relating to the construction of boilers, pressure
vessels, transport tanks, or nuclear components, or the inservice
inspection of nuclear components or transport tanks. Users of the
code should refer to the pertinent codes, standards, laws, regulations, or other relevant documents for safety issues other than
those relating to pressure integrity. Except for Sections XI and XII,
and with a few other exceptions, the rules do not, of practical necessity, reflect the likelihood and consequences of deterioration in
service related to specific service fluids or external operating environments. In formulating the rules, the Committee considers the
needs of users, manufacturers, and inspectors of pressure vessels.
The objective of the rules is to afford reasonably certain protection of life and property, and to provide a margin for deterioration in service to give a reasonably long, safe period of usefulness.
2
Construction, as used in this Foreword, is an all-inclusive term comprising materials, design, fabrication, examination, inspection, testing, certification, and pressure relief.
Advancements in design and materials and evidence of experience
have been recognized.
This Code contains mandatory requirements, specific prohibitions, and non-mandatory guidance for construction activities and
inservice inspection and testing activities. The Code does not address all aspects of these activities and those aspects that are not
specifically addressed should not be considered prohibited. The
Code is not a handbook and cannot replace education, experience,
and the use of engineering judgment. The phrase engineering
judgement refers to technical judgments made by knowledgeable
engineers experienced in the application of the Code. Engineering judgments must be consistent with Code philosophy, and such
judgments must never be used to overrule mandatory requirements
or specific prohibitions of the Code.
Certain points in these paragraphs should be stressed. Section I
covers the construction (materials, design, fabrication, examination, inspection, testing, certification, and pressure relief) of boilers, that is, it covers new construction only. Other rules cover repair
and alteration of boilers and pressure vessels in service, for example, the National Board Inspection Code [8] (see also section 1.6.4
in this chapter) and the API Pressure Vessel Inspection Code, API
510 [9]. Although there is general agreement that Section I should
apply to new replacement parts, and such parts are usually specified that way, until the appearance of the 1996 Addenda, Section I
had no clear provisions dealing with replacement parts other than
how they should be documented. That addenda included changes
to PG-106.8 and PG-112.2.4 that require the manufacturers of replacement parts to state on the data report form (the documentation that accompanies the part, see section 1.7.10, Certification by
Stamping and Data Reports) whether or not the manufacturer is
assuming design responsibility for those replacement parts. Please
note that this was further clarified with the addition of a new designator, “PRT,” in the 2015 Edition (see 1.7.10.3, Certification
Marks and How They are Obtained, for more information.) Also
mentioned in the foreword is the objective of the rules: reasonably certain protection of life and property, but with a margin for
deterioration in service to provide a reasonably long, safe period of
usefulness. This is an acknowledgment of the fact that no equipment lasts forever, and that boilers do have a finite life.
The Foreword (of all book sections) now includes cautions that
the designer using computers is responsible for assuring that any
programs used are appropriate and are used correctly. It is also now
mentioned that material specifications of recognized national or
international organizations other than ASTM and AWS may be acceptable in ASME construction (see 1.7.1.3 and 1.7.1.4).
The Section I rules have worked well over many years. They
were based on the best design practice available when they were
written, and have evolved further on the same basis. Rules have
been changed to recognize advances in design and materials, as
well as evidence of satisfactory experience. The needs of the users,
manufacturers, and inspectors are considered, but safety is always
the first concern. Today, the committee that governs, interprets,
and revises Section I is called the Standards Committee on Power
Boilers, also known as BPV I, (it is also sometimes referred to as
the Section I Committee, but that is an unofficial designation.).
Another basis for the success of Section I is the Committee’s insistence that the rules are to be understood as being general and are
not to be interpreted as approving, recommending, or endorsing any
proprietary or specific design, or interpreted as limiting a manufacturer’s freedom to choose any design or construction that conforms
to the Code rules. The Committee deems the manufacturer to be
ultimately responsible for the design of its boiler and leaves certain
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-3
aspects not covered by Section I to the manufacturer. Traditionally,
the manufacturer has recognized this and borne the responsibility
for such things as functional performance of the boiler, thermal
expansion and support of the boiler and its associated piping, and
the effects of thermal stress, wind loading, and seismic loading on
the boiler. Further evidence of the flexibility and reasonableness of
Section I—and another key to its success as a living document—is
found in the second paragraph of the preamble:
The Code does not contain rules to cover all details of design
and construction. Where complete details are not given, it is
intended that the manufacturer, subject to the acceptance of
the Authorized Inspector, shall provide details of design and
construction which will be as safe as otherwise provided by
the rules in the Code.
This important paragraph, along with similar wording in PG16.1, has provided a way to accept new or special designs for
which no rules are provided by allowing the designer to prove to
the satisfaction of an Authorized Inspector (AI); (see definition in
Section 1.7.9, Third-Party Inspection) that the safety of the new
design is equivalent to that of traditional designs. If necessary, the
AI can seek the assistance of the organization by which he or she is
employed, a so-called Authorized Inspection Agency, in determining the acceptability of new designs.
According to one of the definitions cited above, a code is a body
of laws arranged systematically for easy reference. Although this
may be true of Section I, it is not at first easy to use or understand,
as it is a collection of rules that have been revised and expanded
over the years with very little accompanying explanation. These
rules mandate the fundamental construction features considered
necessary for a safe boiler (one that is a safe pressure container),
but typically do not provide any advice on how to design a boiler
from the standpoint of what size or arrangement of components
should be used. There are no provisions, for example, dealing with
the thermal performance and efficiency of the boiler or how much
steam it will produce (other than for some approximate guidelines
for judging the adequacy of the safety-valve discharge capacity).
It is assumed that the boiler manufacturer or designer already has
this knowledge, presumably from experience or available technical literature. Many rules seem, and indeed are, arbitrary; but as
explained before, they were originally written to incorporate what
was considered good practice in the industry.
Code construction under the rules of Section I takes place as
follows: The ASME accredits a manufacturer (i.e., after appropriate review and acceptance of the manufacturer’s quality control
system, the ASME authorizes the manufacturer to engage in code
construction). The manufacturer then constructs, documents, certifies, and stamps the boiler in compliance with the rules of Section I. The manufacturer’s activities are monitored and inspected
by a third party (the AI). The boiler is then acceptable to jurisdictions with laws stipulating ASME construction of boilers. Section
VIII [10] construction (of pressure vessels) and Section IV [11]
construction (of heating boilers) is carried out in similar fashion.
1.3
THE ORGANIZATION OF SECTION I
The original edition of Section I was not well organized. Over
the years the contents changed as portions were moved into other
sections of the code and more and more provisions were added. In 1965, following a precedent set by the Committee with
Section VIII, the Committee completely reorganized Section I
into its present, improved arrangement of parts, in which each
part covers a major topic or particular type of boiler or other
Section I device. That reorganization was merely a reshuffling
of the existing requirements, with no technical changes from
the previous version. Here is the arrangement based on the 2015
Edition:
t Foreword
t Statements of Policy on the Use of the Certification Mark and
Code Authorization in Advertising
t Statement of Policy on the Use of ASME Marking to Identify
Manufactured Items
t Submittal of Technical Inquiries to the Boiler and Pressure
Vessel Standards Committees
t Personnel
t Preamble
t Summary of Changes
t Part PG, General Requirements for All Methods of Construction
t Part PW, Requirements for Boilers Fabricated by Welding
t Part PR, Requirements for Boilers Fabricated by Riveting
t Part PB, Requirements for Boilers Fabricated by Brazing
t Part PL, Requirements for Locomotive Boilers
t Part PWT, Requirements for Watertube Boilers
t Part PFT, Requirements for Firetube Boilers
t Part PFH, Optional Requirements for Feedwater Heater
(When Located within Scope of Section I Rules)
t Part PMB, Requirements for Miniature Boilers
t Part PEB, Requirements for Electric Boilers
t Part PVG, Requirements for Organic Fluid Vaporizers
t Part PFE, Requirements for Feedwater Economizers
t Part PHRSG Requirements for Heat Recovery Steam Generators
t Mandatory Appendix II, Standard Units for use in Equations
t Mandatory Appendix III, Criteria for Reapplication of a Certification Mark
t Mandatory Appendix IV, Local Thin Areas in Cylindrical
Shells and in Spherical Segments of Heads
t Mandatory Appendix V, Additional Rules for Boilers Fabricated
by Riveting
t Mandatory Appendix VI, Establishing Governing Code
Editions, Addenda, and Cases for Boilers and Replacement
Parts
t Nonmandatory Appendix A, Explanation of the Code Containing Matter Not Mandatory Unless Specifically Referred
to in the Rules of the Code
t Nonmandatory Appendix B, Positive Material Identification
Practice
t Endnotes
t Index
The user will notice that Section I skips from Part PHRSG to
Mandatory Appendix II, with no Mandatory Appendix I. Prior to
the 2013 Edition, Section I included Mandatory Appendix I, Submittal of Technical Inquiries to the Boiler and Pressure Vessel
Committee. Starting with the 2013 Edition, the content from that
appendix is now located in the front of Section I before the listing
of committee personnel as shown above.
The front of the volume contains the Foreword and Preamble, which provide a fundamental description of Section I and its
application. First time users of Section I often skip the Foreword
and the Preamble and proceed directly to the body of the book.
This is a mistake because this introductory material contains a
1-4 t Chapter 1
good deal of useful information about Section I, its scope, how
the Code works, and definitions of various types of power boilers.
Also in the front of the book is a current listing of the personnel of
the Boiler and Pressure Vessel Committee, which administers all
sections of the Code, and information on how to submit technical
inquiries to that committee.
1.3.1
The Parts of Section I
1.3.1.1 Part PG. Part PG is the first major section of Section I
and provides general requirements for all methods of construction.
It covers such important topics as scope and service limitations;
permitted materials; design; cold forming of materials; requirements for piping, valves, fittings, feedwater supply, and safety
valves; permitted fabrication methods; inspection; hydrostatic
testing; and certification by stamping and data reports. The general
requirements of Part PG must be used in conjunction with specific
requirements given in the remainder of the book for the particular
type of construction or type of boiler used. A number of Part PG
topics are covered in later sections of this chapter.
1.3.1.2 Part PW. The second major section is called Part PW,
Requirements for Boilers Fabricated by Welding. Since almost all
boilers are now welded, this is a broadly applicable part containing
much important information. It covers such topics as responsibility for welding; qualification of welding procedures and welders;
acceptable weld joint designs; types of welding permitted; postweld heat treatment of welds; radiography, inspection, and repair
of welds; and testing of welded test plates. The rules of Part PW
are described and explained further in Section 1.7.4, Welding and
Postweld Heat Treatment.
1.3.1.3 Part PR. With the gradual replacement of riveting by
welding, the Committee decided that no purpose was served by
continuing to maintain and reprint in each edition the special rules
applicable to riveted construction, Part PR. Accordingly, the 1974
and subsequent Editions of Section I mandate the use of Part PR
rules as last published in the 1971 Edition. This all changed with
the publication of the 2013 Edition.
Riveted construction has been used extensively in the locomotive industry in both historical and hobby locomotives. When the
Committee formed a new committee to look at incorporating modernized rules for locomotive boilers (see 1.3.1.5, Part PL), that
committee determined that the industry would also benefit from
updated rules for riveting. While mandating the use of Part PR
from the 1971 Edition worked for a time, it began to pose limitations for the industry over time. One example is that some of the
referenced materials were no longer being manufactured. With the
publication of the revised rules in Part PR (and associated rules
in A-1 through A-6 of Nonmandatory Appendix A and in the new
Mandatory Appendix V), the industry now has a modern set of
rules for riveting. This includes controls for set up and execution
of riveted joints, a listing of modern materials acceptable for rivets,
a requirement that longitudinal riveted joints in drums be of buttand double strap construction (elimination of riveted lap seams in
drum fabrication), and updated lap seam rules for steam domes.
1.3.1.4 Part PB. The next section, Part PB, Requirements for
Boilers Fabricated by Brazing, first appeared in the 1996 Addenda
to the 1995 edition of Section I. Although brazing had long been
used in the construction of certain low-pressure boilers, no brazing
rules had ever been provided in Section I. Part PB brazing rules
resemble Part PW welding rules, but are much less extensive.
One notable difference is that the maximum design temperature
depends on the brazing filler metal being used and the base metals
being joined. Maximum design temperatures for the various brazing filler metals are given in Table PB-1. Brazing procedures and
the performance of brazers must be qualified in accordance with
Section IX by methods similar to those described in section 1.7.4
for qualifying weld procedures and welders. The design approach
used for determining the strength of brazed joints is given in PB-9:
the manufacturer must determine from suitable tests or from experience that the specific brazing filler metal selected can provide a
joint of adequate strength at design temperature. The strength of
the brazed joint may not be less than that of the base metals being
joined. This strength is normally established by the qualification
of the brazing procedure. If the manufacturer desires to extend the
design temperature range normally permitted by Table PB-1 for
the brazing filler metal selected, the manufacturer must conduct
two tension tests of production joints: one at design temperature,
T, and one at 1.05 T. The joints must not fail in the braze metal.
Some acceptable types of brazed joints are illustrated in Figure
PB-15. Non-destructive examination of brazed construction relies
primarily on visual examination, supplemented by liquid penetrant
examination if necessary. PB-49 provides guidance on inspection
and any necessary repairs.
The remainder of Section I is composed of parts providing special rules applicable to particular types of boilers or other Section I
components, such as feedwater heaters.
1.3.1.5 Part PL. A committee was formed in 2010 to look at
publishing a modern set of rules for locomotive boilers. Prior to
that, the last time the ASME Boiler and Pressure Vessel Code contained rules for locomotive boilers was the 1952 Edition of Section
III (Section III later became Rules for Construction of Nuclear
Facility Components, first published in 1963). While locomotive boilers are not as prevalent as they were in the early 1900s,
there is an industry that maintains and operates both historical
and hobby locomotive boilers. The result of this modernization,
Part PL, was first published in Section I in the 2015 Edition. As
noted above, this committee has also helped to modernize Part
PR, Requirements for Boilers Fabricated by Riveting (see 1.3.1.3).
1.3.1.6 Part PWT. Part PWT, Requirements for Watertube
Boilers, is a very brief collection of rules for this type of boiler,
with some of the rules pertaining to construction details rarely
used today. All large high-pressure boilers are watertube boilers.
Most construction rules for these boilers are found in Parts PG and
PW, and Part PWT is merely a brief supplement. It is, however,
the only place where rules for the attachment of tubes to shells and
headers of watertube boilers can be found. Part PWT is an example
of the retention by Section I of certain old rules and construction
details because some manufacturers might still use them.
1.3.1.7 Part PFT. Part PFT, Requirements for Firetube Boilers,
is a much more extensive set of rules, still very much in use for
this popular type of boiler, which is quite economical for generating low-pressure steam. Except in special cases, the large-diameter
shell places a practical limit on design pressure at about 400 psi,
although most firetube boilers have lower pressures. Part PFT
covers many variations within the type in considerable detail.
Requirements cover material, design, combustion chambers and
furnaces, stayed surfaces, doors and openings, domes, setting,
piping, and fittings.
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-5
A good deal of Part PFT dates back to the original 1915 edition
of Section I. However, extensive revisions were made in the 1988
Addenda. A much larger selection of materials was permitted, and
allowable stresses for the first time became a function of temperature, as is the case elsewhere in the Code. In addition, the design
rules for tubes and circular furnaces under external pressure were
made consistent with the latest such rules in Section VIII, from
which they were taken. In the mid-1990s, Part PFT was further
revised and updated.
Part PFT was further revised in the 2011a Addenda based on
an inquiry received regarding immersion electric heating elements
(see 1.3.1.10, Part PEB). That inquiry, on electric boilers covered
by Part PEB, highlighted to the Committee that the only place that
Section I addressed external pressure, other than access and inspection openings in PG-28, was in Part PFT. To make the external pressure rules available for other boilers or devices, the rules
for thickness and MAWP for components under external pressure
were relocated from the Part PFT to PG-28.
1.3.1.8 Part PFH. Part PFH, Optional Requirements for
Feedwater Heater (When Located Within Scope of Section I
Rules), applies to feedwater heaters that fall within the scope
of Section I by virtue of their location in the feedwater piping
between the Code-required stop valve and the boiler. A feedwater
heater, for the purposes of this part, is a heat exchanger in which
feedwater to be supplied to a boiler is heated by steam or water
extracted from the boiler or the prime mover. The reader will
note that while a feedwater heater and the feedwater economizers
covered in 1.3.1.12, Part PFE, both result in heating feedwater, the
source of heat is different (steam or water as opposed to flue gas).
Under these circumstances, the heater may be constructed in compliance with the rules in Section VIII, Pressure Vessels, Division
1, for unfired steam boilers, which are more strict in a number of
respects than those applicable to ordinary Section VIII vessels, as
explained in section 1.4.4, The Use of Section VIII Vessels in a
Section I Boiler.
The primary side of the heater must be designed for a higher
pressure than the Maximum Allowable Working Pressure (MAWP)
of the boiler, per 122.1.3 of Power Piping, ASME B31.1. (Remember: This heater is in the feedwater piping, and rules for the design
of feedwater piping are within the scope of B31.1.) Part PFH also
stipulates how the heater is to be stamped and documented.
If a feedwater heater within the scope of Section I is equipped
with isolation and bypass valves, there is a possibility that it could
be exposed to the full shut-off head of the boiler feed pump. PG58.3.3 cautions about this and notes that control and interlock systems are permitted to prevent excessive pressure. (It is impractical
to provide sufficient safety valve capacity in these circumstances.)
1.3.1.9 Part PMB. Part PMB, Requirements for Miniature
Boilers, contains special rules for the construction of small boilers
that do not exceed certain limits (16 in. [400 mm] inside diameter
of shell, 20 ft² [1.9 m²] of heating surface, 5 ft³ [0.14 m³] gross volume, 100 psig [700 kPa] MAWP). Because of this relatively small
size and low pressure, many requirements normally applicable to
power boilers are waived. These have to do with materials, material marking, minimum plate thickness, postweld heat treatment
and radiography of welds, and feedwater supply. To compensate
somewhat for this relaxation of the normal rules, and to provide
an extra margin of safety, PMB-21 stipulates that miniature boiler
pressure vessels are to be given a hydrostatic test at a pressure
equal to three times the MAWP.
1.3.1.10 Part PEB. This part, Requirements for Electric
Boilers, was added to Section I in 1976. Until that time, manufacturers had been building these boilers as Section VIII devices.
However, Section VIII had no specific rules for electric boilers and
the various openings, valves, and fittings normally mandated by
Section I (blowoff, drain, water gage, pressure gage, check valve,
etc.). Also, the manufacturers were not formally assuming design
responsibility for the boiler. The rules of Part PEB remedied these
shortcomings.
Part PEB covers electric boilers of the electrode and immersion
resistance type only and doesn’t include boilers in which the heat is
applied externally by electrical means. The boiler pressure vessel
may be a Section I vessel or may have been constructed as an unfired steam boiler under special rules of Section VIII, Division 1.
Note that those rules require radiography and postweld heat treatment, as explained later, in section 1.4.4, under The Use of Section
VIII Vessels in a Section I Boiler.
Under the provisions of Part PEB, a manufacturer can obtain
from the ASME a Certificate of Authorization to use the Certification Mark and the “E” designator (see section 1.7.10, Certification
by Stamping and Data Reports), which authorizes the manufacturer to assemble electric boilers (by installing electrodes and trim
on a pressure vessel). The manufacturer must obtain the pressure
vessel from an appropriate Certificate Holder. The E-designator
holder is limited to assembly methods that do not require welding
or brazing. Electric boilers may, of course, also be constructed by
certificate holders authorized to use the Certification Mark with an
S or M designators. The E-designator holder becomes the manufacturer of record, who is responsible for the design of the electric
boiler. This is stipulated in PEB-8.2.
The Data Report Form P-2A (see section 1.7.10, Certification by Stamping and Data Reports) for electric boilers is in two
parts: one for the vessel manufacturer and one for the manufacturer responsible for the completed boiler, who may be a certificate
holder authorized to use the Certification Mark with an E, S, or M
designator. If the vessel is constructed to the Section VIII, Division 1, rules for unfired steam boilers, it must be stamped with the
Certification Mark with a U designator and documented with a U-1
or U-lA Data Report (these are Section VIII data report forms). In
such a case, the Section I master Data Report P-2A must indicate
this fact, and the U-lA form must be attached to it.
Electric boilers of the resistance element type must be equipped
with an automatic low-water cutoff, which cuts the power before
the surface of the water falls below the visible part of the gage
glass. Such a cutoff is not required for electrode type boilers (which
use the water as a conductor), since these in effect cut themselves
off when the water level falls too low.
Part PEB was revised in the 2010 Edition based on intent interpretation I-10-15 (shown below). PEB-2.4 was revised to include
heating elements enclosed in pipe that is then immersed in water. This interpretation then prompted a change to Part PFT (see
1.3.1.7, Part PFT).
Interpretation: 1-10-15
Subject: PEB-2.4 (2007 Edition)
Date Issued: June 30, 2010
Question: A boiler is heated by electric heating elements.
Each element is inserted into a pipe well with the opposite
end closed. Each pipe well extends into the boiler and may
be installed by welding, threading, or flange. The pipe well
is immersed in the fluid of the boiler and separates the fluid
1-6 t Chapter 1
from the electric heating element. Is it the intent that such an
assembly meets the definition of an immersed resistance heating element in PEB-2.4?
Reply: Yes.
There were also some changes to Part PEB in the 2013 and 2015
Editions that are worth mentioning. The 2011a Addenda to Section
VIII included a new appendix (Mandatory Appendix 41, Electric
Immersion Heater Element Support Plates). This appendix was
based on the rules in Section VIII Part UHX, specifically those in
UHX-12 which provides rules for the design of u-tube tubesheets.
The Committee felt that these rules would be beneficial to flanged
electric immersion heaters constructed to Section I so added a new
paragraph, PEB-8.3, in the 2013 Edition pointing to Section VIII
Mandatory Appendix 41. Unfortunately, the way the paragraph
was written only provided two choices, follow the rules in Section
I paragraphs PG-31 through PG-35 or use Section VIII Mandatory Appendix 41. This inadvertently disallowed the more common practice of using standard pressure parts under PG-11 and also
could be interpreted to not permit parts constructed by a Section
VIII Certificate Holder and documented on a Form U-2 Manufacturer’s Partial Data Report. This was addressed by the Committee
in intent interpretation I-13-21 together with a revision to PEB-8.3
in the 2015 Edition.
Interpretation: 1-13-21
Subject: PEB-8.3 (2013 Edition)
Date Issued: February 25, 2014
Question (1): Is it the intent of PEB-8.3 to prohibit the use of
a miscellaneous pressure part per PG-11 as a manufacturer’s
standard pressure part?
Reply (1): No.
Question (2): Is it the intent of PEB-8.3 to prohibit the use
of pressure parts manufactured by a Section VIII, Division
1, “U” Certificate Holder when the element support plate is
designed per the rules of Section VIII, Division 1, Mandatory Appendix 41 and documented with a U-2 Partial Data
Report?
Reply (2): No.
1.3.1.11 Part PVG. This part provides rules for organic fluid
vaporizers, which are boiler-like devices that use an organic fluid
(such as Dowtherm™) instead of steam as the working fluid. The
principal advantage of using these organic fluids is that they have
much lower vapor pressures than water at a given temperature.
Thus they are particularly suitable for heating in industrial processes requiring high temperatures at low pressure. On the other
hand, these liquids are both flammable and toxic, and Part PVG
contains a number of special provisions because of these drawbacks.
To prevent the uncontrolled discharge of organic fluid or vapor to the atmosphere, the use of gage cocks is prohibited. Safety
valves must be of a totally enclosed type that will discharge into
a pipe designed to carry all vapors to a safe point of discharge.
The safety valve lifting lever normally required on Section I safety
valves is prohibited, and valve body drains are not mandatory. Because the polymerization of organic fluids can cause clogging or
otherwise adversely affect the operation of safety valves, and also
because the valves have no lifting levers by which they can be
tested periodically, PEB 12.2 requires the removal and inspection
of these valves at least yearly. This is a rare instance of Section I
reaching beyond its normal new-construction-only coverage.
As a further means of reducing unintentional discharge of organic fluid to the environment by leakage through safety valves,
and to prevent the gumming up of these valves, Section I permits
installation of rupture disks under the valves. This is the only use
of such disks permitted by Section I. Special rules are also provided for calculating safety valve capacity. The required capacity
of these valves is based on the heat of combustion of the fuel and
the latent heat of vaporization of the organic fluid. This capacity is
determined by the manufacturer.
1.3.1.12 Part PFE. This part, added in the 2015 Edition,
provides rules for feedwater economizers. This part was added
primarily to provide rules regarding when an economizer must be
constructed to Section I and when it may be constructed to either
Section I or Section VIII and also when austenitic stainless steels
may be used. It also provides information on selecting both the
maximum allowable working pressure and design temperature.
1.3.1.13 Part PHRSG. This part provides rules for a heat
recovery steam generator, HRSG, that has as its principal source of
thermal energy a hot gas stream having high ramp rates and temperatures such as the exhaust of a gas turbine. Such an HRSG may
utilize supplemental firing and may have one or more superheaters, reheaters, evaporators, economizers, and/or feedwater heaters,
which are housed in a common gas path enclosure. The sections
cannot be individually isolated from the gas stream.
1.3.1.14 Mandatory Appendices. Following is a list of contents in the 2015 Edition.
t Mandatory Appendix II—Standard Units for use in Equations
t Mandatory Appendix III—Criteria for Reapplication of a
Certification mark
t Mandatory Appendix IV—Local Thin Areas in Cylindrical
Shells and in Spherical Segments of Heads
t Mandatory Appendix V—Additional Rules for Boilers Fabricated by Riveting
t Mandatory Appendix VI—Establishing Governing Code
Editions, Addenda, and Cases for Boilers and Replacement
Parts
1.3.1.15 NonMandatory Appendix A. Nonmandatory Appendix
A contains a great deal of miscellaneous information, some of it
dating from the first edition. Much of this is nonmandatory explanatory material, unless it is specifically referred to in the main body of
Section I. The diversity of the subjects can be seen from this list of
contents:
t Riveted Joints
t Braced and Stayed Surfaces
t Method of Checking Pressure Relief Valve Capacity by
Measuring Maximum Amount of Fuel that can be Burned
t Automatic Water Gages
t Fusible Plugs
t Proof Tests to Establish Maximum Allowable Working Pressure
t Suggested Rules Covering Existing Installations
t Pressure Relief Valves for Power Boilers
t Repairs to Existing Boilers
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-7
t Examples of Methods of Computation of Openings in Vessel
Shells
t Examples of Computation of Allowable Loading on Structural
Attachment to Tubes
t Example Computations of Typical Nozzle Fittings Attached
by Rivets
t Preheating
t Heating and Cooling Rates for Postweld Heat Treatment
t Rounded Indication Charts
t Methods for Magnetic Particle Examination (MT)
t Methods for Liquid Penetrant Examination (PT)
t Quality Control System
t Acceptance of Testing Laboratories and Authorized Observers
for Capacity Certification of Pressure Relief Valves
t Cylindrical Components Under Internal Pressure
t Data Report Forms and Guides
t Codes, Standards and Specifications Referenced in the Text
t Guide to Information Appearing on Certificate of Authorization
t Sample Calculations for External Pressure Design
t Guidance for the Use of U.S. Customary and S.I. Units in the
ASME Boiler and Pressure Vessel Code
t Guidelines Used to develop S.I. Equivalents
t Soft Conversion factors
1.3.1.16 Nonmandatory Appendix B Positive Material Identification Practice. This appendix is provided as a guide for use
by a Manufacturer developing a Positive Material Identification
Practice that may form part of their material control system.
1.3.1.17 Endnotes. With the publication of the 2011a Addenda,
all footnotes have been compiled and relocated to a single location
at the end of Section I entitled “Endnotes.”
1.3.1.18 Index. The index provides a cross reference of some of
the more common terms used throughout Section I.
1.3.2
Interpretations
Since 1977, the ASME has published all the replies from the
ASME staff on behalf of the ASME Boiler and Pressure Vessel
Committee to inquiries on the interpretation of Section I (and
also the other book sections). Despite the fact that interpretations
are said not to be a part of the Code, they can be very useful
in explaining its application and in resolving disputes regarding
what the Code intends which is why most Code users and AIs
generally accept interpretations as the equivalent of Code rules.
Also note that as stated in the front matter of Section I, “ASME
accepts responsibility for only those interpretations of this document issued in accordance with the established ASME procedures
and policies, which precludes the issuance of interpretations by
individuals.”
Interpretations are supposed to clarify the existing rules and are
not to create “rules by interpretation,” with one exception. That
exception is what is referred to as an intent interpretation. Sometimes when the committee reviews an inquiry, they determine that
the existing code words do not really convey what the committee
intended and must be revised for clarity. These “intent interpretations” will typically include the words “Is it the intent…” as part of
the question and the paragraph will be revised in the next edition
or addenda to further clarify. An example of this is interpretation
I-10-23. In the 2011a Addenda, PHRSG-3.4 was revised to clarify
that capacity is required “…such that condensate pooling in superheaters and reheaters is prevented.”
Interpretation: 1-10-23
Subject: PHRSG-3.4 (2010 Edition)
Date Issued: April 4, 2011
Question: Is it the intent of “quick-opening” type valve in
PHRSG-3.4 to provide draining within a specific time?
Reply: No. The intent of PHRSG-3.4 is to provide draining
capacity such that condensate pooling is prevented.
Historically, a purchaser of a new edition of any Code section
would receive the interpretations for that section that were issued
since the last addenda. With each addenda for the edition purchased, they would also receive any interpretations issued since
the last edition or addenda. When the publication cycle for the
Code was changed after the 2011a Addenda (see 1.6.5, Effective
Dates of the Code and Code References), new interpretations were
posted in January and July at http://cstools.asme.org/interpretations.
cfm. Following the 2015 Edition, interpretations will not be included in editions; they will be issued in real time in ASME’s Interpretations Database at http://go.asme.org/Interpretations. When
the interpretations were published with the Code books, many users found it convenient to bind all of the interpretations together for
easy reference. To continue that, ASME has included the historical
interpretations in the database referenced above.
An example of the designation of a Section I Interpretation is
I-98-27. The “I” signifies that the interpretation pertains to the
rules of Section I; the “98,” is the year the “27,” is a sequential
number. Before 1983, the year of the interpretation denoted the
year it was issued. After that, it indicated the edition of Section I
to which it pertained, unless a specific year was mentioned in the
interpretation. For example, the subject for interpretation I-10-22
is PG-58.3.2 (2007 Edition), Steam Stop-Check Valves, which indicates that it applies to the 2007 Edition even though it has a 10
designation. Starting with I-15-01, the year designation will again
be the year issued and the interpretation will identify in the subject
line which edition it applies to.
1.3.3
Code Cases
One of the many definitions of the word case is “a special situation,” which is a good description of the circumstances covered
by what the Committee calls a Code Case. In the early application
of the first edition of the Code, users sought Committee guidance
for circumstances not specifically covered by the Code or when the
intent of the Code rules was not clear. The Committee considered
a number of these special situations and issued formal guidance in
the form of what it called a Case. This is the origin of the practice
of issuing numbered Code Cases. In those days, no distinction was
made between a Case and what we now call an interpretation.
Today, Code Cases are used for several purposes:
t To provide for early implementation of new or revised Code
rules, since a Code Case can be approved and published
more quickly than the text of the Code can be revised. A text
change can take well over a year after approval by the ASME
Boiler and Pressure Vessel Standards Committee before it
is published, while a Code Case can be approved in as little as one Codeweek meeting cycle (Codeweek is the name
given to the week of Code committee meetings held four
times a year.). Thus, a Code Case may be usable two or three
months after the inquiry is submitted to the ASME Boiler and
Pressure Vessel Standards Committee.
1-8 t Chapter 1
t To permit the use of new materials or new forms of construction not covered or not otherwise permitted by existing Code
rules, when the need is urgent.
t To gain experience over a period of time with new materials,
new forms of construction, or new design rules before changing the Code to include them. This is particularly useful for
rapidly evolving technology.
Initially, Code Cases had a limited life, usually three years.
They automatically expired at that point unless the Committee reaffirmed them for another three years. In March 2005, the Committee took action to eliminate Code Case expiration dates. This
means that all Code Cases listed in Supplement 3 of the 2004 Code
Edition and beyond will remain available for use until annulled by
the Committee.
Code Cases may be used beginning with the date of approval
shown on the Case. Annulled Code Cases will remain in the Numeric
Index until the next Edition, at which time they will be deleted.
The digit following a Case number is used to indicate the number of times a Code Case has been revised. Code Cases are arranged in numerical order and each page of a Case is identified at
the top with the appropriate Case number.
Code Cases may be annulled at any time by the Committee.
Usually, a Code Case is annulled six months after its contents have
been incorporated and published in the Code. Note that Code Cases
are nonmandatory; they are permissive only. In effect, they are an
extension of the Code. Most Code Cases require the Code Case
number to be listed on the Manufacturers’ Data Report (see section
1.7.10 for a description of data reports). Although there used to be
pressure to incorporate all Code Cases into the Code as soon as
adequate experience had been gained with their use, it is now recognized that some Cases do not lend themselves to incorporation
and should be left as Cases indefinitely. One problem with Code
Cases is that some jurisdictions will not allow their use. Manufacturers are thus cautioned to check acceptability of Code Cases with
the jurisdiction where the boiler will be installed.
With each new Code edition, the ASME publishes all current
Code Cases in two Code Case books: Code Cases: Boilers and
Pressure Vessels [12] and Code Cases: Nuclear Components [13].
Supplements with the latest Cases and annulments are now sent
quarterly to purchasers of the Code Case books until the publication
of the next edition of the Code, when a new Code Case book must be
purchased. Theoretically, issuing the new Cases quarterly enables
the publication of new Cases as soon after each ASME Boiler and
Pressure Vessel Standards Committee meeting as possible. In addition, Cases are made available on an ASME website from the time
they are passed until they are then sent out as a supplement (https://
cstools.asme.org/csconnect/CommitteePages.cfm?Committee
=N20050000&CommitteeCodeCases=yes). This site does not provide access to all Cases, just those that have passed since the last
supplement was sent out.
1.4
SCOPE OF SECTION I:
PRESSURE LIMITS AND EXCLUSIONS
1.4.1
Scope
Section I applies to several types of boilers and components of
boilers, such as economizers, superheaters, reheaters, and in some
circumstances feedwater heaters. Although its title is Power Boilers,
the scope of Section I is somewhat broader. The Preamble to Section I explains that it covers power boilers, electric boilers, miniature
boilers, high-temperature water boilers, heat recovery steam generators, solar receiver steam generators, some fired pressure vessels,
and organic fluid vaporizers. Since the precise definitions of these
various types of boilers are not generally known, the following definitions, found in footnotes to the preamble, are helpful:
(1) Power boiler—a boiler in which steam or other vapor is
generated at a pressure of more than 15 psi (100 kPa) for
use external to itself.
(2) Electric boiler—a power boiler or a high-temperature water boiler in which the source of heat is electricity.
(3) Miniature boiler—a power boiler or high-temperature water boiler in which the limits in PMB-2 are not exceeded.
(4) High-temperature water boiler—a water boiler intended
for operation at pressures in excess of 160 psi (1.1 MPa)
and/or temperatures in excess of 250°F (120°C).
(5) Heat Recovery Steam Generator (HRSG)—a boiler that has
as its principal source of thermal energy a hot gas stream
having high ramp rates and temperatures such as the exhaust of a gas turbine.
(6) Solar receiver steam generator—a boiler system in which
water is converted to steam using solar energy as the principal source of thermal energy. The solar energy is typically
concentrated onto the solar receiver through the use of an
array of mirrors that focuses solar radiation on the heat
transfer surface.
(7) Fired pressure vessel—reheaters, isolable superheaters,
economizers located outside the limits of boiler external piping, and non-integral separately fired superheaters.
Section I doesn’t provide an explicit definition of an organic fluid
vaporizer, which is a boiler-like device that uses an organic fluid
instead of steam as the working fluid. However, the last paragraph
of the Preamble states that a pressure vessel in which an organic
fluid is vaporized by the application of heat resulting from the combustion of fuel shall be constructed under the provisions of Section
I. (Those provisions are found in Part PVG.) Thus, so far as Section
I is concerned, an organic fluid vaporizer is a boiler-like device in
which an organic fluid is vaporized as just described. (Note that a
key factor is the vaporization of the organic fluid. If the organic
fluid is merely heated without vaporizing, the device does not fall
within the scope of Section I; it might fall instead under the scope
of Section VIII as a pressure vessel.) The Preamble then provides
a notable exception to the Section I definition of an organic fluid
vaporizer: “Vessels in which vapor is generated incidental to the
operation of a processing system, containing a number of pressure
vessels such as are used in chemical and petroleum manufacture,
are not covered by the rules of Section I.” Again, if Section I rules
do not cover these vessels, what rules do? The answer is the rules of
Section VIII, Pressure Vessels. Those rules cover all kinds of pressure vessels, including in some cases fired pressure vessels.
Although the origin of the above exception to Section I dominion is uncertain, a possible explanation can be surmised. Note
that the vessel in question would probably be used in a chemical
plant or petroleum refinery. Such plants are normally owned and
operated by large companies with a capable engineering staff and
well-trained operators. Those companies can usually demonstrate
a good record of maintenance and safety. Furthermore, vaporizing
organic liquids inside pressure vessels is a routine matter for them.
They might also argue that it really does not make much difference
whether a properly designed vessel is built to the rules of Section
I or Section VIII, nor does it matter whether the source of heat is
from direct firing, from hot gases that may have given up some of
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-9
their heat by having passed over a heat-transfer surface upstream,
or from a hot liquid that is being processed. There are also economic reasons why an Owner might prefer a Section VIII vessel
over a Section I vessel, as explained later in the discussion of fired
versus unfired boilers.
The Preamble does not explain the precise meaning of “vapor
generation incidental to the operation of a processing system.” It
apparently means the generation of vapor in a vessel or heat exchanger that is part of a processing system in a chemical plant or
petroleum refinery where this vapor generation is only a minor or
secondary aspect of the principal business of the plant, such as refining oil. Thus, certain equipment normally constructed to Section
I rules could, under this exception, be constructed instead to the
rules of Section VIII, provided the appropriate authorities in the
jurisdiction where the equipment is to be installed have no objection. These so-called jurisdictional authorities have the last word in
deciding which Code section applies (see How and Where Section
I is Enforced and Effective Dates in Section 1.6).
There is also some imprecision in the use and meaning of the
term power boiler. This term is sometimes understood to mean
a boiler with steam that is used for the generation of power, as
opposed, for example, to a boiler with steam that is used for
chemical processing or high-pressure steam heating. However, according to the definition in the Preamble, a boiler that generates
steam or other vapor at a pressure greater than 15 psi for external
use is considered by Section I to be a power boiler, irrespective
of how the steam might be used. Although exceptions exist, most
jurisdictional authorities follow the ASME Code in defining and
categorizing boilers and pressure vessels.
Note from the definition of a power boiler that the steam or other
vapor generated is for use external to the boiler. This is supposed to
distinguish a power boiler from certain other pressure vessels, such
as autoclaves, that may similarly generate steam or vapor at a pressure greater than 15 psi but not generally for external use. These
pressure vessels, often used as process equipment in the chemical
and petroleum industries, and for cooking or sterilization in other
industries, are designed to meet the rules of Section VIII.
From the Preamble definitions, it is apparent that a hightemperature water boiler, which generally produces pressurized hot
water for heating or process use, is not considered a power boiler.
However, as a practical matter, the particular characterization of a
device by Section I as a power boiler or something else is less important than the fact that it is indeed covered by Section I rules.
The Preamble explains that the scope of Section I covers the
complete boiler unit, which is defined as comprising the boiler
proper and the boiler external piping. This very important distinction needs further explanation. The term boiler proper is an
unusual one, chosen to distinguish the boiler itself from its external
piping. The boiler proper consists of all the pressure parts comprising the boiler, such as the drum, the economizer, the superheater, the reheater, waterwalls, steamgenerating tubes known as
the boiler bank, various headers, downcomers, risers, and transfer
piping connecting these components. Any such piping connecting
parts of the boiler proper is called boiler proper piping. The boiler
external piping is defined by its extent: it is the piping that begins
at the first joint where the boiler proper terminates and extends to
and includes the valve or valves required by Section I.
The importance of all these definitions and distinctions is that
the construction rules that apply to the boiler proper and boiler
proper piping are somewhat different from those that apply to the
boiler external piping. This is explained in Section 1.5, Distinction
Between Boiler Proper Piping and Boiler External Piping.
The Preamble also explains that the piping beyond the valves
required by Section I is not within the scope of Section I. Thus
these valves define the boundary of the boiler, and Section I jurisdiction stops there. Note that the upstream boundary of the scope
of Section I varies slightly, depending on feedwater valve arrangements. Different valve arrangements are required for a single boiler
fed from a single source, as opposed to two or more boilers fed
from a common source, with and without bypass valves around
the required regulating valve (see the solid and dotted lines shown
in Figure PG-58.3.1(a), reproduced in this chapter). The required
boiler feed check valve is typically placed upstream of the feed stop
valve, except that on a single boiler-turbine unit installation, the
stop valve may be located upstream of the check valve. Changes in
the Section I boundary can have some significance in the choice of
design pressure for the feed water piping and valves, which is governed by the rules of B31.1, Power Piping (see paragraph 122.1.3).
An exception to this coverage of boiler piping is found in the
treatment of the hot and cold reheat piping between the boiler and
a turbine, (see Figure PG-58.3.1(c), reproduced in this chapter)
which is excluded from the scope of Section I. Occasionally, someone asks how and why reheat piping was left outside the scope of
Section I. The explanation offered some years ago by a senior member of the Committee is as follows: Although reheaters date back to
the earliest days of Section I, the rising steam pressures employed
in large utility boilers in the 1940s led to their increased use. The
reheat piping became larger, heavier, and more complex. In those
days, the General Electric Company and Westinghouse made virtually all of the turbines used in the United States, and it was customary for those turbine manufacturers to take responsibility for the
design of the reheat piping. Whenever some Committee members
suggested that it might be time to consider bringing reheat piping into the scope of Section I, those two companies objected. On
the basis of their long, successful experience, they convinced the
Committee that such a change was unnecessary and that they were
perfectly capable of designing that piping. Thus the reheat piping
remained outside the scope of Section I.
In the late 1980s, failures of hot reheat piping occurred at
two major utilities, with injuries and loss of life. This reopened
the question of whether Section I should cover reheat piping and
whether the failed piping, designed in the 1960s, might not have
failed had it been within the scope of Section I. (Current Section I
rules call for all boiler components to be manufactured, inspected,
certified, and stamped under a quality control system, a requirement imposed in 1973. Moreover, any piping within the scope of
Section I is generally inspected yearly, with the rest of the boiler,
although finding potential leaks or failures under the insulation is
not so readily accomplished.) However, investigators were not able
to agree on the causes of the failures, and the idea of bringing the
reheat piping within Section I jurisdiction died for lack of support.
Code coverage of this reheat piping and also of piping beyond
the boiler external piping varies. Normally in power plant design,
the owner or the architect engineer will select the B31.1, Power
Piping Code, for the reheat piping, and either that Code or the
B31.3, Process Piping Code [14] (formerly called the Chemical
Plant and Petroleum Refinery Piping Code), for the piping beyond
the boiler external piping. The reader should also note that the jurisdiction (state or province) may have laws mandating use of one
or the other of these two Codes to cover piping that isn’t within the
scope of Section I.
Some unfired steam boilers are constructed to the requirements
of Section VIII, as permitted by the preamble. Section VIII rules
deal only with the vessels themselves; they do not deal with any
1-10 t Chapter 1
(Source: ASME SECTION I)
piping attached to the vessels. In such cases, the choice of an appropriate design Code for the piping may be left to the plant designers; otherwise, the jurisdictional authorities may mandate a
particular piping Code.
1.4.2
Pressure Range of Section I Boilers
As explained in the Preamble, Section I covers boilers in which
steam or other vapor is generated at a pressure of more than 15 psi
(100 kPa) for use external to the boiler. (All pressures used in
Section I are gage pressure.) For high-temperature water boilers,
Section I applies if either the pressure exceeds 160 psi (1.1 MPa) or
the temperature exceeds 250°F (120°C). The vapor pressure of water at 250°F (120°C) is approximately 15 psi (100 kPa). Thus, if the
water temperature is less than 250°F (120°C), saturation pressure
is less than 15 psi (100 kPa). Boilers designed for pressures below
15 psi (100 kPa) are usually constructed to the rules of Section IV,
Heating Boilers. However, such units could be built, certified, and
stamped as Section I boilers if all the requirements of Section I are
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-11
(Source: ASME SECTION I)
met. Section I has no upper limit on boiler design pressure. The
design pressure (also called by Section I the Maximum Allowable
Working Pressure, or MAWP) of large, natural-circulation boilers
used by electric utilities can be as high as 2975 psi (20 MPa). At
higher pressures, approaching the critical point of water and steam
3206 psia (21.4 MPa) and 705.4°F (372.5°C), the difference in
density between steam and water becomes so small that natural
circulation in the boiler would be inadequate. The design pressure of what is known as a forced-flow steam generator with no
fixed steam and water line can be substantially higher, approaching
5000 psi (35 MPa) for advanced ultra-super critical boilers.
1.4.3
Fired versus Unfired Boilers
Section I rules are intended primarily for fired steam or hightemperature water boilers and organic fluid vaporizers. There are,
however, boilers called unfired steam boilers that do not derive
their heat from direct firing. These unfired steam boilers may be
constructed under the provisions of either Section I or Section
VIII, Pressure Vessels. The definition of an unfired steam boiler
is not as clear as it might be, which has led to some confusion and
occasional disagreement between the Committee on Power Boilers
and the Committee on Pressure Vessels. The Preamble to Section
I states that:
A pressure vessel in which steam is generated by the application of heat resulting from the combustion of fuel (solid,
liquid, or gaseous) or from solar radiation shall be classified
as a fired steam boiler.
Unfired pressure vessels in which steam is generated shall
be classed as unfired steam boilers with the following exceptions:
(a) vessels known as evaporators or heat exchangers;
(b) vessels in which steam is generated by the use of heat
resulting from operation of a processing system containing a number of pressure vessels such as used in the
manufacture of chemical and petroleum products.
It is these exceptions that cause the confusion, for several reasons. Sometimes it is not apparent whether a boiler using waste heat
is fired or unfired. Furthermore, it may be difficult to distinguish
1-12 t Chapter 1
between an unfired steam boiler using waste heat and certain heat
exchangers also using waste heat. Another difficulty arises from
the source of the waste heat. If it stems from the combustion of
fuel, the device is generally considered fired. However, some jurisdictions have permitted boilers to be considered unfired if they use
waste heat from a combustion turbine. The presence of auxiliary
burners in a boiler using waste heat from another source would
cause that boiler to be considered fired. This was affirmed in the
first question and reply in Interpretation I-92-20.
Question (1): If the main heat source of a Section I boiler is
the exhaust from a combustion turbine, and a secondary fired
heat source, e.g., a duct burner, is provided for intermittent
use, is the boiler classified as a fired boiler?
Reply (1): Yes.
The reader should note that this interpretation was issued before
Part PHRSG was added in the 2007 Edition and before the Preamble was revised in 2008 to include heat recovery steam generators
within Section I. With those two changes, Section I has clarified
that heat recovery steam generators are within Section I, even if
they do not have supplemental firing.
All ASME Code sections routinely caution users that laws or
regulations at the point of installation may dictate which Code section applies to a particular device and that those regulations may
be different from or more restrictive than Code rules. The jurisdictions may also have rules that define whether a device is considered a boiler or a heat exchanger and whether it is considered fired
or unfired.
Electric boilers can be considered fired or unfired, depending
on the circumstances. An inquiry on this subject was answered by
Interpretation I-81-01, as follows:
Question: The preamble of Section I defines an electric boiler
as “a power boiler or a high-temperature water boiler in
which the source of heat is electricity.” Would you define
whether or not an electric boiler is considered to be a fired or
an unfired steam boiler?
Reply: PEB-2 provides criteria for determining if an electric
boiler is considered to be a fired or an unfired steam boiler. An
electric boiler where heat is applied to the boiler pressure vessel externally by electric heating elements, induction coils, or
other electrical means is considered to be a fired steam boiler.
An electric boiler where the medium (water) is directly heated
by the energy source (electrode type or immersion element
type) is considered to be an unfired steam boiler.
An unfired steam boiler constructed to Section VIII must meet
rules more stringent than run-of-the-mill Section VIII vessels. For
example, these rules require additional radiographic examination,
postweld heat treatment, and possibly impact testing of materials
and welds, as more fully described in the next section, The Use of
Section VIII Vessels in a Section I Boiler.
Some owners of steam generating vessels would prefer to avoid,
if possible, the classification of boiler or fired boiler because most
states and provinces require an annual shutdown for inspection of
boilers, although some states permit longer periods of operation.
The interval between inspections mandated for Section VIII vessels is typically much longer, permitting longer uninterrupted use
of the equipment.
One of the criteria some Committee members use to distinguish
between fired and unfired boilers is whether a flame from a poorly
adjusted burner can impinge directly on pressure parts and overheat them. This is clearly a possibility in a fired boiler, and it is
one reason for some of the conservativeness of Section I rules, and
for the typical practice of requiring annual outages for inspection.
By contrast, hot gases from some upstream source are less likely
to cause overheating of those same pressure parts because they are
less likely to be misdirected and, presumably, no actual flames can
reach the downstream steam generating pressure parts.
An interesting change in the 2015 Edition was the addition of
solar receiver steam generator to the preamble (see 1.4.1, Scope).
These steam generators use solar energy and not combustion of a
fuel as their primary source of thermal energy. With the increased
interest in using solar energy for power generation, ASME contracted with a consultant for a gap analysis of ASME Boiler and
Pressure Vessel Codes as they relate to concentrated solar power
(CSP) systems where the solar radiation is concentrated on a receiver. As part of this gap analysis, it was determined that the Jurisdictions in the US with the greatest CSP potential would not all
classify the various systems the same, some classified a particular system (such as the solar receiver steam generator mentioned
above) as a boiler while others classified them as pressure vessels.
Based on this gap analysis, the Committee formed a new committee to address solar power (see 1.8, Future Changes) and the
first step was the definition in the preamble of solar receiver steam
generators.
1.4.4
The Use of Section VIII Vessels in a Section I
Boiler
Usually all parts of a Section I boiler are constructed to Section I rules, but there are a few exceptions worth noting. Pressure
vessels for electric boilers (see PEB-3), unfired steam boilers (see
code case 1855, below), and feedwater heaters that fall under Section I jurisdiction by virtue of their location in the feedwater piping (see PFH-1.1) are among those boiler components that may
be constructed under the special rules for unfired steam boilers in
UW-2(c) of Section VIII Division 1. One other type of Section
VIII vessel that can be used in a Section I boiler is mentioned in
the next-to-last paragraph of the preamble. That vessel is an expansion tank used in connection with what is defined in footnote 4 to
the preamble as a high-temperature water boiler. This is the only
mention of such tanks in Section I, and nothing is said about their
construction having to meet the special Section VIII requirements
for unfired steam boilers. Thus it seems that an ordinary Section
VIII vessel would serve the purpose.
Although it might seem that components built to Section VIII
are just as safe as those built to Section I and therefore should be
virtually interchangeable, this is unfortunately not the case. When
Section I does permit the use of Section VIII vessels, it insists
on invoking certain special Section VIII rules for unfired steam
boilers. These rules are a little more stringent than those for runof-the-mill Section VIII vessels. The rules are found in U-1(g)(1),
UG-16(b)(3), UG-125(b) and UW-2(c) of Section VIII, Division 1.
The most important requirements called out in these several paragraphs are the following:
t Safety valves are to be furnished in accordance with the
requirements of Section I insofar as they are applicable.
t For design pressures exceeding 50 psi (350 kPa), radiography
of all butt-welded joints is required, except for circumferential welds that meet the size and thickness exemptions of
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-13
UW-11(a)(4). (Those exemptions cover welds in nozzles that
are neither greater than NPS 10 (DN 250) nor thicker than
118 in. (29 mm)).
t Postweld heat treatment is required for vessels constructed of
carbon and low-alloy steel.
t A minimum thickness of ¼ in. (6 mm) is required for shells
and heads, exclusive of any corrosion allowance.
Another extra requirement imposed on an unfired steam boiler
constructed to Section VIII rules applies to all Section VIII vessels
made of carbon and low-alloy steels. The designer must establish
a Minimum Design Metal Temperature (MDMT), the lowest temperature expected in service at which a specified design pressure
may be applied. Unless the combination of material and thickness
used is exempt by the curves of UCS-66 at the MDMT, impact
testing of the material is required, and the Weld Procedure Qualification would also have to include impact testing of welds and heataffected zones. This is not explicitly mentioned in the paragraphs
dealing with unfired steam boilers because it is a requirement that
was added to Section VIII in the mid-1980s, long after those other
paragraphs were written and probably because the Committee
members assumed that everyone knew that impact testing was routinely required unless the vessel materials met certain exemptions
provided in UCS-66.
What is also notable about these rules for unfired steam boilers is the fact that the ordinary Section VIII exemptions for postweld heat treatment (PWHT) are not available, even for welds in
relatively thin P-No. 1 materials. Moreover, the Section VIII nondestructive examination rules must be followed even if volumetric
examination might not be required by Table PW-11.
An example of the consequences of overlooking these somewhat obscure rules occurred when a boiler manufacturer placed
an order for a sweetwater condenser with a manufacturer of Section VIII pressure vessels without specifying that the condenser,
as a type of feedwater heater, had to meet the UW-2(c) rules for
unfired steam boilers. (A sweetwater condenser is a shell-and-tube
heat exchanger connected directly to the boiler drum that receives
saturated steam from the drum on the shell side and has feedwater
going to the drum inside the tubes. The steam condenses on the
tubes, giving up its heat to the feedwater and providing a supply of
water pure enough to use as spray water in the superheater. These
condensers are used where the regular feedwater supply is not of
sufficient quality to use as spray water.)
After the condenser was installed and the boiler was ready for
the hydrostatic test, the authorized inspector (AI) inquired about
the presence of a Section VIII vessel in a Section I boiler. He was
told that it was a feedwater heater furnished to the rules of Part
PFH of Section I. The AI reviewed those rules and asked about
the required radiography and postweld heat treatment, which it
turned out had not been done because the boiler manufacturer had
ordered the condenser as an ordinary Section VIII vessel. The condenser had to be cut out of the installation, shipped back to the
manufacturer, radiographed, and given a postweld heat treatment.
This PWHT had to be conducted very slowly and carefully, using thermocouples during heating and cooling to avoid too great a
temperature difference between shell and tubes, which could cause
excessive loading on the tubes, tube welds, or tubesheet. Fortunately, the radiography and PWHT were quickly and successfully
accomplished and the condenser was reinstalled in the boiler with
minimal delay.
Three circumstances have been mentioned in which Section VIII
Division 1 vessels can be used as part of a Section I boiler: feedwater
heaters, under Part PFH; pressure vessels for electric boilers, covered under Part PEB; and a “Section VIII Unfired Steam Boiler in a
Section I System,” covered under the provisions of code case 1855.
The title of case 1855 is a little confusing, as is the case itself. Some
feel that the case only permits complete unfired steam boilers (such
as rotor air coolers used in some combined cycle plants) to be included in a Section I system while others feel that it permits individual parts or components (such as drums, headers, economizers, etc.)
to be constructed to Section VIII Division 1 and included in a Section I system. Some of the confusion has been eliminated through
the publication of Part PFE (see 1.3.1.12) and two additional Code
Cases, 2485 and 2559. Case 2485 was issued to permit steam drums
for a HRSG to be constructed to Section VIII Division 2. This allowed design by analysis to be used to reduce thickness of the drum
and improve its fatigue tolerance for cyclic service. After this case
was issued, the obvious question was then “Why should this only
apply to HRSG drums and not to other components or other boiler
types?” The Committee then issued Case 2559 which permits Section VIII Division 2 components to be installed in Section I boilers
without limiting the type of component or type of boiler. With each
of these cases, the Committee imposed additional rules beyond the
requirements of Section VIII (such as materials, pressure testing,
certification, and documentation).
1.5
DISTINCTION BETWEEN BOILER
PROPER PIPING AND BOILER
EXTERNAL PIPING
For many years, Section I made no distinction regarding the
piping of a boiler; it was all considered just boiler piping. In the
late 1960s, some members of the Committee decided that Section
I rules were no longer adequate to cover the design of modern
high-pressure, high-temperature steam piping because the Section
I rules for the design of boiler proper piping are actually quite limited, covering the design of pipe for internal or external pressure
only. Far more extensive rules are provided in the B31.1 Power
Piping Code. In addition to pressure, those rules cover many other
loads that piping might be subject to, such as mechanical loads
that may develop from thermal expansion and contraction of the
piping, impact loading, gravity loads, and seismic loads. Although
such comprehensive rules are not provided by Section I for the
design of the boiler proper piping, boiler manufacturers over the
years have managed to design this piping—often by using the design methods of B31.1—so that it serves its purpose in a satisfactory manner.
After due consideration, the Committee decided to divide all
piping within the scope of Section I into two categories. The piping that was actually part of the boiler (such as downcomers, risers,
and transfer piping) was designated as boiler proper. Construction
rules for this piping were retained in Section I. The piping that led
to or from the boiler (such as feedwater, steam, vent, drain, blowoff, and chemical feed piping) was designated into a new category,
boiler external piping, an appropriate name since it is typically
external to the boiler. This piping was defined by its extent: from
the boiler to the valve or valves required by Section I (the boundary of the complete boiler unit). These valves were also defined as
part of the boiler external piping. In 1972, responsibility for most
aspects of the construction of this piping was transferred from Section I to the Power Piping Code, ASME B31.1. That is, rules for
material, design, fabrication, installation, and testing of boiler external piping were now contained in B31.1, but Section I retained
1-14 t Chapter 1
its usual certification requirements (with Authorized Inspection
and stamping). Designers of boiler piping, whether boiler proper
or boiler external piping, are thus faced with a mixed bag of interrelated rules and should be aware of a number of special provisions
and potential pitfalls.
To clarify the distinction between the two categories of piping,
the Committee expanded Figure PG-58.3.1 to show each category of
piping. A comparable figure appears in the front of B31.1. Complicating matters further, a new category of piping—called non-boiler
external piping—had to be established within B31.1. Non-boiler
external piping is the piping beyond the scope of Section I that is
connected to the boiler external piping. Figure PG-58.3.1 has been
expanded into three figures as of the 2015 Edition, Figure PG58.3.1(a), Figure PG-58.3.1(b), and Figure PG-58.3.1(c). Figure PG58.3.1(a) is reproduced in this chapter for ready reference.
Transferring coverage of the boiler external piping to B31.1
made available, at a stroke, detailed and comprehensive rules not
provided by Section I for such important aspects of piping design as
flexibility analysis and hanger design. By retaining complete coverage of piping within the boiler proper jurisdiction, Section I continued its policy of providing minimal guidance in the design of this
piping, which has traditionally been left to the boiler manufacturers.
The transfer of the design of boiler external piping to B31.1
has resulted in some negative consequences. For one thing, an
entirely different committee governs the Power Piping Code. Inquiries about boiler external piping typically are answered by that
committee, and occasional differences develop between it and the
Committee on Power Boilers. In the early 1990s, this problem was
addressed by an action of the Board of Pressure Technology Codes
and Standards, which reaffirmed that the B31.1 section committee
had primary responsibility for the rules governing the design of
boiler external piping. Also, despite the best efforts of both committees, minor differences that exist between the respective rules
result in different treatment of piping on the same boiler, depending on whether it is boiler external piping or boiler proper (e.g.,
requirements for postweld heat treatment and volumetric examination differ for the two categories of piping). While both sets of
rules are more than adequate, unwary designers who do not pay
sufficient attention to what type of piping they are designing can
run into expensive delays should an AI notice at the last minute that
the piping does not meet the appropriate rules.
1.6
HOW AND WHERE SECTION I IS
ENFORCED AND EFFECTIVE DATES
1.6.1
United States and Canada
Section I is a set of rules for the construction of boilers. These
rules are not mandatory unless they are adopted into the laws of
a government. The applicable territorial and political units within
a government are usually referred to as jurisdictions, a term that
derives from the range of their governmental authority. A jurisdiction can be a government subdivision, that is, state, province,
county, or city. If there happen to be no jurisdictional requirements regarding Code coverage, the purchaser of a boiler may
specify to the manufacturer that construction to Section I rules is
a requirement.
Currently (2016), laws requiring Section I construction of boilers have been adopted by all but two states (Idaho and Wyoming
being the exceptions) and by all of the provinces of Canada. In addition to the states and provinces, about 16 cities and counties also
have laws requiring Section I construction.
Except as noted above, states and provinces with boiler laws
typically enforce the Code by means of an appointed board or
commission that writes and revises boiler rules and an appointed
chief inspector with the necessary enforcement staff. The jurisdictional authorities also depend on the efforts of AIs working for
Authorized Inspection Agencies, whose function is to ensure that
the boiler manufacturer has complied with Section I (see Section
1.7.9, Third-Party Inspection.) These same authorities also have
the responsibility for overseeing the care and operation of boilers
once they are completed.
The National Board of Boiler and Pressure Vessel Inspectors
provides a registration service for ASME B&PVC products. Users
should note that some of the jurisdictions that require the use of
Section I may also require registration with the National Board.
Even when not required by the jurisdiction, many Manufacturers
choose to register their products for ease of retrieval of the ASME
Manufacturer’s Data Reports.
Before an organization may register their product, they must obtain a Certificate of Authorization to Register from the National
Board. This is covered in the National Board publication, NB-264,
Criteria for Registration, available on the National Board website
(www.nationalboard.org).
1.6.2
International Acceptance
Section I is recognized internationally as an acceptable construction
code, along with other codes and standards, such as EN 12952, the
European Standard for Water-tube boilers and auxiliary installations.
At one time the Mexican mechanical engineering society AMIME
translated Section I into Spanish for use in Mexico, but it was apparently little used, in part due to the difficulty of keeping up with the
ongoing changes in Section I. Before the 1970s, the ASME allowed
only U.S. and Canadian companies to engage in ASME Code Construction. However, as a result of legal action at that time, the ASME
has been under specific instructions from a consent decree requiring
cooperation with non-U.S. manufacturers to allow their accreditation
as ASME Certificate Holders, provided those manufacturers’ quality
control systems pass the ASME review process. There are now many
manufacturers outside of North America who are ASME Certificate
Holders and can engage in Code Construction of boilers and pressure
vessels. More recently, the provisions of North American Free Trade
Agreement (NAFTA) and General Agreement on Tariffs and Trade
(GATT) require a level playing field for domestic and foreign manufacturers, and the ASME has been active in seeking acceptance of its
code by the European Community.
The ASME encourages participation in the various committees
by users from around the globe. There are many Committee members from outside the United States but there are still others which
may wish to contribute but circumstances may prevent them from
meeting the expectations of committee membership. To address
this and further the international use of Section I, the Committee
has established International Working Groups (IWG). An IWG is
a group of stakeholders based in a common geographic location
outside the United States that functions in a subordinate role to
the committee. The IWGs hold their meetings in their geographic
location and are expected to both develop and review proposed
standards actions for consideration by the Committee. This provides benefit to the IWG members through better understanding of
code requirements and the opportunity to influence those requirements. The Committee benefits from a better understanding of the
needs of users outside the United States. Currently (2016), there
are two IWGs for Section I, one in India (established in 2014) and
one in Germany (established in 2015).
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-15
For field-assembled boilers (those too large to be completed
in the shop), full compliance with the ASME Code requires that
field assembly be accomplished by appropriate certificate holders
and also that an Authorized Inspection Agency provide the necessary field inspection. Jurisdictions outside of North America do
not generally insist on full compliance with the ASME Code but
some purchasers or owners may still require it. When full compliance with the ASME Code is not required by the jurisdiction
or owner, the field assembly of some projects is performed by an
organization that does not hold the appropriate ASME Certificate
of Authorization. Consequently, although the components of such
boilers may have been designed and manufactured in accordance
with Section I, the completed boilers do not meet all the requirements that would permit full Code stamping and certification. In
this circumstance, the use of the ASME Certification Mark or even
a reference to ASME on the nameplate is prohibited (see The Statement of Policy on the Use of ASME Marking to Identify Manufactured Items in the front of Section I).
1.6.3
Adoption of Uniform Requirements
by Jurisdictional Authorities
To provide the advantages of uniformity of construction and
inspection, the Uniform Boiler and Pressure Vessel Laws Society, Inc., was founded in 1915, just three months following the
official adoption of the first ASME Boiler Code. This society provided model legislation to jurisdictions and supported nationally
accepted codes, such as Section I and Section VIII, as standards
for the construction of boilers and pressure vessels. In general,
the society encouraged adoption of uniform requirements by the
jurisdictional authorities. Manufacturers traditionally strongly supported this effort because it promoted the manufacture of economical standard products and obviated custom designed features for
different jurisdictions. Besides the model legislational promotion
activity of the society, it provided a publication entitled SYNOPSIS
of Boiler and Pressure Vessel Laws, Rules and Regulations [15],
which was arranged by states, cities, counties, provinces and other
international jurisdictional entities. Originally this covered just the
United States and Canada but was expanded to include information
about the laws in a number of other countries.
Now that most states have boiler laws and many have pressure
vessel laws, the original mandate of the UBPVLS society can be
considered essentially fulfilled. As a consequence of the low volume sale of boilers, resulting from a recession, funding for the society’s efforts diminished substantially and it was found necessary
to dissolve this historical significant organization. Many of the
functions it provided have been picked up by the National Board
(see 1.6.4 below). A National Board Synopsis of Boiler and Pressure Vessel Laws, Rules and Regulations, NB-370, is available on
the National Board website (www.nationalboard.org).
1.6.4
National Board Inspection Code
Section I covers only new construction, and once all of its requirements for a new boiler have been met and the necessary data
reports have been signed, Section I no longer applies. In jurisdictions that accept the National Board Inspection Code (NBIC) [8],
that code is applicable for installation of new boilers and inservice
inspection, repair, or alteration. The stated purpose of the NBIC
is to “maintain the integrity of pressure-retaining items after they
have been placed into service by providing rules and guidelines
for inspection, repair, and alteration, thereby ensuring that these
objects may continue to be safely used.” A guiding principle of
the NBIC is to continue to follow the rules of the original code of
construction insofar as practicable. When there is no such code,
or when it is unknown, the ASME Code is used as a default. Any
welding used in repairs or alterations must be done in accordance
with the code used for the original construction. For example, for
ASME Section I construction, the National Board requires that any
welding used in repairs or alterations must be done to the same
strict standards as required by Section I, using welders and weld
procedures qualified in accordance with Section IX; the exception to this is that the NBIC has permitted the use of some ANSI/
AWS Standard Welding Procedure Specifications since 1995 but
the ASME did not until mid-2000. (In a fairly significant change,
the 2000 Addenda to Section I and Section IX, and the other book
sections of the code, provided for the use of a number of ANSI/
AWS Standard Welding Procedure Specifications with some additional restrictions, as explained in Section 1.7.4, Welding and
Postweld Heat Treatment.) The National Board Inspection Code
also requires that all the safety appurtenances of a Section I boiler
(e.g., safety valves and gages) be maintained in good order. Thus
it could be said that the National Board Inspection Code takes up
where Section I leaves off. As of 2016, 44 states of the United
States and 12 provinces and territories of Canada have made the
NBIC mandatory, and most other jurisdictions will accept it. Many
locations outside of the United States and Canada that do not have
their own laws regarding repairs and alterations of pressure equipment will also often accept the use of the NBIC.
1.6.5
Effective Dates of the Code
and Code References
Since the Code is in a constant state of evolution, to apply it
properly, the user needs to understand the effective dates of the
Code and Addenda. In 2010 the ASME decided to change the
method and frequency of publishing the Code. Up until that time,
the Code was issued every three years (2004, 2007 etc.) with an
addendum issued annually. The date of publication was July 1st
of each calendar year. The change proposed in 2010 was to issue
the Code on a 2-year cycle, without an interim addenda. To implement this change, the 2010 edition, which contains everything
in the 2007 edition (including the 2008 and 2009 addenda), plus
additional changes that were approved subsequent to the 2009 addenda but in time for the 2010 edition publication, was published
with changes noted in the front matter as “Summary of Changes”
and noted in the code book with [10]. In 2011 the code book was
republished in its entirety with new code changes noted with (a).
This edition of the Code was entitled “2010 ASME Boiler & Pressure Vessel Code, 2011a Addenda. There was no addenda issued
in 2012 and the next publication was the 2013 Edition. The Code
will continue to be published on a two year cycle (2015 Edition,
2017 Edition, etc.). To implement some changes that have been
approved by the Committee and are awaiting publication, information on how to access errata and special notices has been added to
the Summary of Changes in the front of the Code. The following is
from the 2015 Edition.
After publication of the 2015 Edition, Errata to the BPV Code
may be posted on the ASME Web site to provide corrections
to incorrectly published items, or to correct typographical or
grammatical errors in the BPV Code. Such Errata shall be
used on the date posted.
Information regarding Special Notices and Errata is published by ASME at http://go.asme.org/BPVCerrata.
1-16 t Chapter 1
Revisions become mandatory six months after the date of issue,
except for boilers contracted for before the end of the six-month
period. In effect, this gives a manufacturer a six-month grace period during which any Code changes affecting new contracts are
optional. Note that once the edition of Section I to be used for the
construction of the boiler is established, the manufacturer is not
obliged to implement any changes made in subsequent addenda
or editions. This is a practical approach that recognizes that any
changes to Section I are now incremental and are very unlikely to
have any influence on safety. One exception to this general principle is if the change is deemed critical to the intended service conditions of the boiler or part. These changes need to be considered
by the manufacturer. An example of this would be if the allowable
stresses for a material were significantly reduced. In such cases, it
might be prudent for the manufacturer of as yet uncompleted components to use the new, lower allowable stresses.
The edition and addenda of B31.1 to which the boiler external
piping is ordinarily constructed (unless a later version is selected)
is found in the Appendix of Section I in Table A-360: Codes,
Standards, and Specifications Referenced in Text.
The Committee has received numerous inquiries about selecting
the governing edition and addenda of the Code for the boiler, boiler
parts, and boiler external piping. To further clarify the issue, a new
Mandatory Appendix VI, Establishing Governing Code Editions,
Addenda, and Cases for Boilers and Replacement Parts was added
in the 2013 Edition.
1.7
FUNDAMENTALS OF SECTION I
CONSTRUCTION
The technique used by Section I to achieve safe boiler design
is a relatively simple one. It requires all those features considered necessary for safety (e.g., water glass, safety valve, pressure gage, check valve, and drain) and then provides detailed
rules governing the construction of the various components
comprising the boiler. This approach is analogous to the old saying that a chain is no stronger than its weakest link. For a boiler,
the links of the figurative chain are the materials, design (formulas, loads, allowable stress, and construction details), fabrication techniques, welding, inspection, testing, and certification by
stamping and data reports. If each of these elements meets the
appropriate Section I rules, a safe boiler results. The boiler can
then be described as a Section I boiler, meaning one constructed
to meet all the requirements of Section I of the ASME Boiler &
Pressure Vessel Code. An important element of this construction
process is a quality control program intended to ensure that the
code has been followed. Each aspect of the process will now be
discussed.
1.7.1
Materials
1.7.1.1 How Materials are Ordered. Materials are a fundamental link in the chain of Code construction, and great care is taken to
ensure their quality. The Code does this by adopting material specifications that have first been developed by the American Society
for Testing Materials, the ASTM. The ASME material specifications are thus usually identical to those of the ASTM. The ASTM
issues specifications designated by letter and number; for example,
A-106, Seamless Carbon Steel Pipe for High-Temperature Service.
When the ASME adopts ASTM specifications, it adds the letter S.
The equivalent ASME specification is thus SA-106.
The ASME, or SA, specifications are used as purchase specifications. Each specification contains a variety of information appropriate to that product and deals with how the material is ordered, the
manufacturing process, heat treatment, surface condition, chemical
composition requirements, tensile and yield requirements, hardness requirements, various test requirements, and how the material
is to be marked. The purchaser may also invoke supplementary,
nonmandatory requirements dealing with such things as stress relief, nondestructive examination, limits on chemistry (within the
range permitted by the specification) and additional testing. All of
these requirements have evolved over the years in response to the
needs of the users.
The purchaser orders by specification number, and the supplier
certifies that the material complies with that specification. In most
cases, a Certified Material Test Report, giving the results of various
tests required by the specification, is furnished with the material.
1.7.1.2 Using Section II. Section II of the Code, Materials, is a
compilation of all the material specifications adopted by the ASME
for use by the various book sections of the Code. However, as a
general rule, a material cannot be used for pressure parts unless it
is also adopted and listed within the section of the Code covering
the construction. Section I lists permitted materials in PG-5 through
PG-14. PW-5 adds further requirements for materials used in
welded construction. In addition, Section I sets temperature limits
for the use of the various materials; they must be used within the
temperature range for which allowable stress values (often called
design stresses) are provided.
With the publication of the 1992 edition of the Code on July 1,
1992, the allowable stress tables that formerly appeared in Sections I, III, and VIII were consolidated and reformatted into a single volume, Section II, Part D. This consolidation was supposed to
facilitate uniformity among those Code sections that use the same
criteria for establishing allowable stress. (Note that some sections,
such as Section VIII, Division 2, use different criteria, which generally result in higher allowable stresses than those of Section I
and Section VIII, Division 1). The new arrangement lost the convenience of having the allowable stresses included in Section I.
Fortunately the ASME has made many of the tables in Section II
available electronically to the user. This was originally done by supplying a CD with the hard copy of the Code but is now done by providing login credentials for a website which contains these tables.
1.7.1.3 Use of Non-ASME Materials and Material Not Fully
Identified. Both Section I and Section VIII, Division 1, have long
had provisions (PG-10 and UG-10) dealing with the acceptance of
material that is not fully identified. These provisions involve demonstrating that the material in question complies with chemical
requirements and physical properties within the permitted range
of an acceptable ASME material specification. In 1987, these
provisions were expanded to provide more guidance on what must
be done and who may do it when a material is requalified as the
equivalent of an acceptable ASME material. These changes also
aid in the recertification of material manufactured to international
specifications, such as DIN or JIS, as the equivalent of ASME
specifications suitable for Section I or Section VIII construction.
1.7.1.4 Use of International Material Specifications. With
the increasing emphasis on global competition, the Committee
has sought ways in which to gain wider international acceptance
of ASME Code construction. This is a two-way street, and the
ASME recognizes the need to remove unnecessary barriers to
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-17
the use of ASME construction in the hope that other countries
will reciprocate. One of these barriers was the ASME’s previous insistence that only ASME or ASTM materials be used in
ASME construction. Recognizing that many areas of the world
have economic constraints or local rules that may necessitate the
use of non-ASME materials, the ASME relaxed its policy, and in
1997 approved the first two non-ASTM material specifications
for inclusion in the 1998 addenda to Section II. Those two specifications cover a Canadian structural steel, CSA-G40.21 (similar
to SA-36), and a European steel plate, EN 10028-2 (similar to
SA-516 Grade 65). In the 2015 Edition, sixteen non-ASTM specifications have been approved, either entirely or for specific grades,
and their allowable stress values have been added to Section II,
Part D. The ASME establishes the allowable stresses for these
non-ASTM materials on the same basis used for ASTM materials.
For further discussion of the acceptance and use of international
material specifications, see this volume’s chapter on Section II.
1.7.1.5 Special Concerns. There are a number of Section I
material applications that deserve special mention. The use of austenitic stainless steels is one of these and is explained in Endnote
1 to PG-5.5 (note that prior to the 2011a Addenda, Endnotes were
previously published as footnotes within the main body of the
book). Austenitic steels are particularly susceptible to chloride
stress corrosion. Consequently, paragraph PG-5.5 of Section I
limits the use of these steels to what it calls steam-touched service
and prohibits their use for normally water-wetted service where
chlorides might be present, except for gage glass bodies (PG-12),
miniature electric boilers operated on deionized water (PEB-5.3),
and some economizers (PFE-4). Those stainless steels listed
in PG-9.1 for boiler parts (normally water-wetted) are ferritic
stainless steels, which are not susceptible to chloride corrosion.
Another concern is the problem of graphitization that occurs in
some carbon steels after long service at temperatures above 800°F
(425°C). Graphitization can severely affect the strength and ductility of these steels, particularly the heat-affected zone of welds.
Notes in the allowable stress tables caution about this problem.
The use of cast iron and non-ferrous metals is limited by Section
I to those applications mentioned in PG-8.
Material requirements for boiler external piping are contained in
B31.1, Power Piping, 123.2.2. That paragraph permits a manufacturer to use ASTM Specifications equivalent to those of the ASME
by demonstrating that the requirements of the latter have been met.
1.7.1.6 Miscellaneous Pressure Parts. Miscellaneous pressure
parts (see PG-11), such as valves, fittings, and welding caps, are
often furnished as standard parts. Standard parts made to a manufacturer’s proprietary standard or to an ASME standard not adopted
in PG-42, must be made of materials permitted by Section I. When
those parts meet the requirements of the ASME product standards
adopted by reference in PG-42, Section I accepts the materials
listed in those standards. Prior to the 2015 Edition, the use of materials listed in these ASME product standards included an additional
caveat “not of materials specifically prohibited or beyond the use
limitations listed in this Section”. This had never presented a problem until 1992, when Section II, Part D, introduced the composite
stress tables for Sections I, III, and VIII. In those tables, the letters
NP (not permitted) that appear in the columns on applicability of
material for a given book section were applied by default if that
material had not been listed for use in that book section before the
advent of Part D. Therein lies a problem, because there are many
materials listed in the ASME product standards accepted by Section
I by reference in PG-42 that had never been listed in the Section
I stress tables. No AI had previously challenged the use of those
materials in these product standards because their use was (and
still is) explicitly sanctioned by PG-11. However, a problem arose
once the designation NP appeared in Part D. One company found
itself facing the following situation: It had designed and subcontracted to another certificate holder the fabrication of an austenitic
stainless steel superheater with return bends that were purchased as
standard elbows made in accordance with ASME B16.9, FactoryMade Wrought Steel Buttwelding Fittings. The manufacture of
B16.9 elbows starts with pipe or tube made from a material that is
designated only by class and grade (e.g., WP 304) and that meets
the chemical and tensile requirements of SA-403, Specification
for Wrought Austenitic Stainless Steel Pipe Fittings. When the
elbow is completed in accordance with the provisions of SA-403
and ASME B16.9, it is given a new material designation, A-403 or
SA-403, as a fitting. Unfortunately, Section I had never listed that
material, but it had been listed in Section VIII. Accordingly, the
Section II, Part D column for Section I applicability listed SA-403
as NP (not permitted); apparently, it was permitted only for Section
VIII construction.
The AI at the fabricator saw that listing and proclaimed that the
elbows could not be used in Section I construction, a decision that
stopped fabrication of the superheater whose contract specified
heavy daily penalties for late completion. Fortunately, the Authorized Inspection Agency providing the AI at the job site had knowledgeable Code committee members who quickly agreed that the
designation NP should not apply in these circumstances or, rather,
should not mean NP if PG-11 provided otherwise or as long as the
material is not specifically prohibited within the body of Section I.
Section I subsequently issued Interpretation I-92-97, which solved
the problem for these particular fittings, and more generically addressed the issue in Interpretation I-95-38, but did nothing about
the generic problem of the potentially misleading NP designation
in Section II, Part D. An attempt to have the Committee on Materials modify the NP designation with a note referring to PG-11
proved unavailing, so the unwary designer faces a potential trap in
situations similar to the one just described.
Interpretation I-92-97 is as follows:
Question: May SA-403 austenitic fittings made to ASME/ ANSI
standards accepted by reference in PG-42 be used for Section
I steam service?
Reply: Yes.
Interpretation I-95-38 is as follows:
Question: Does PG-9 prohibit the use of ASTM materials for
standard pressure parts which are permitted in PG-11 and
which comply with the American National Standard products
listed in PG-42?
Reply: No, except for materials specifically prohibited or beyond the use limitations of Section I.
PG-11 underwent a complete rewrite for the 2015 Edition. The
Committee formed a task group to review how each of the book
Sections (Section I, Section IV, Section VIII, and Section XII) addressed standard pressure parts and to try to harmonize the requirements across all Sections. Some of the rewrite was just a reordering
of some requirements (for example some of the requirements from
the previous PG-11.3.2 are now in PG-11.4) but other changes
1-18 t Chapter 1
were more significant and are worth mentioning. The first significant change was to the title on PG-11, changing from Miscellaneous Pressure Parts to Prefabricated or Preformed Pressure Parts
Furnished Without a Certification Mark. This clarifies that the
main purpose of this paragraph is to provide rules for which parts
may be used in a boiler without requiring certification of the part
through data reports and stamping of the part. The next significant
change was the elimination of the words “furnished by other than
the Manufacturer responsible for the completed boiler,” clarifying
that the Manufacturer responsible for the completed boiler can use
their own standard parts. Another significant change was related to
the issue above on materials. The wording “not of material specifically prohibited” has been removed, making it clear that materials
listed in the ASME product standards may be used, even if the allowable stress line in Section II Part D shows “NP.” There was also
additional clarity added regarding welding, PWHT, and NDE for
welded parts. One of the most significant changes was the addition
of PG-11.5 which permits and provides controls for when a manufacturer subcontracts welding services to an individual or organization that does not hold an ASME Certificate of Authorization.
1.7.1.7 Electric Resistance Welded (ERW) Materials. When
the code first accepted tubes and pipes formed of electric resistance welded materials, it imposed a 15% penalty on allowable
stress, except for tubes within the boiler setting whose design
temperature was 850°F (455°C) or lower. There was apparently
some doubt about the welding, and normal allowable stress was
permitted only for tubes inside the protective barrier of the setting.
Because of the good service record of these tubes, some thought
was given to removing the penalty on ERW tubes. As a first step in
this direction, in 1988, several Code Cases were passed permitting
the use of ERW tubes at any temperature without the 15% reduction in allowable stress, provided the tubes are given extra nondestructive examination (angle beam ultrasonic inspection and an
electric test in accordance with ASME specification SA-450), are
no larger than 3 ½ in. outside diameter, and are enclosed within
the setting. Subsequently the Code Cases have been incorporated
and annulled. See notes G4 and W13 for the particular materials
in Section II, Part D, Table A1. For pipe and tube that exceeds the
3 ½ in. (89 mm) outside diameter limitation or is located outside
the setting, there is an alternate stress line in Section II, Part D,
Table 1A that retains the 15% reduction.
Code users often wonder just what the term “within the setting”
means, since this term is not defined in Section I. However, various books on boiler construction typically define the setting as the
construction surrounding the boiler and or the tubes: refractory, insulation, casing, lagging, or some combination of these. In former
years, heavy casing and refractory were used so that a case could
be made that a failed tube would not represent much of a danger to
someone standing nearby. With the evolution of simpler and lighter
construction, there now may be only insulation and lagging outside
the tubes or enclosing a header. Although such construction may
not provide so strong a barrier as was the case formerly, the tubes
are still “enclosed within the setting,” and if they meet the other
provisions, they would be entitled to the full allowable stress without the 15% penalty.
1.7.1.8 Non-Pressure Part Materials. Non-pressure parts, such
as lugs, hangers, brackets, and fins, are not limited to being made
of materials listed in the stress tables, but must be of weldable
quality. “Weldable quality” is a rather vague term, and the choice
of non-pressure-part material is thus left to the designer. The fact
that a material is of weldable quality is established when the procedure used to weld it is qualified. For carbon and low-alloy steels,
PW-5.2 also stipulates another requirement for weldability: the
carbon content may not exceed 0.35%.
1.7.2
Design
1.7.2.1 Design Methods. For the most part, Section I uses
an experience-based design method known as design-by-rule.
(Certain other sections of the Code, namely Section III, Subsection
NB, and Section VIII, Division 2, use a newer method, known as
design-by-analysis.) Design-by-rule is typically a process requiring the determination of loads, the choice of a design formula, and
the selection of an appropriate design stress for the material to be
used. Rules for this kind of design are found throughout Section I,
with most being in Part PG (the general rules). Other design rules
are found in those parts of Section I dealing with specific types of
boilers or particular types of construction.
The principal design rules are found in Part PG, paragraphs PG16 through PG-56. There are formulas for the design of cylindrical components under internal pressure (tube, pipe, headers, and
drums), heads (dished, flat, stayed, and unstayed), stayed surfaces,
and ligaments between holes. Rules are also provided for openings
or penetrations in any of these components, based on a system
of compensation in which the material removed for the opening is replaced as reinforcing in the region immediately around
the opening, called the limits of compensation (see PG-36). All
of these formulas involve internal pressure except for the rules in
PG-28 and PG-56. PG-28 provides rules for components under external pressure and PG-56 provides rules for loads from structural
attachments.
The second paragraph of the Preamble contains rules to be applied when design criteria are not given in Section I. Unfortunately
many Code users were not aware of these rules in the Preamble,
so they have been reproduced in paragraph PG-16.1 in the 2009
Addenda. These rules are essentially identical to U-2(g) of VIII1. PG-16.1 offers appropriate analytical methods, rules from other
design codes, or proof test (PG-18, Appendix A-22). Usage of any
of the provisions of PG-16.1 requires acceptance of the Inspector,
and shall provide details of design that will be as safe as those provided by the rules of Section I.
Proof Test is an experience-based method used to establish a
safe design pressure for components for which no rules are given
or when strength cannot be calculated with a satisfactory assurance
of accuracy. In this type of proof test, a full-size prototype of the
pressure part is carefully subjected to a slowly increasing hydrostatic pressure until yielding or bursting occurs (depending on the
test). The maximum allowable working pressure is then established
by an appropriate formula that includes the strength of the material
and a suitable safety factor. In the 1999 addenda, Section I joined
Section VIII in allowing a burst test to be stopped before actual
bursting occurs, when the test pressure justifies the desired design
pressure. The particular component so tested may never be used
for Code Construction (because it might have been on the verge
of failure). The design factor, or so-called safety factor, used in the
burst test formula for ductile materials has been 5 since the 1930s,
when one of the factors used to establish allowable design stress
was one-fifth of the Ultimate Tensile Strength (UTS). That factor
on UTS has been reduced over the years from 5 to 4 (circa 1950)
and from 4 to 3.5 in the 1999 addenda. Thus the design factor used
in the burst test was seen to be out of date and due for a reduction.
In 2000, as an interim measure, both Section I and Section VIII
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-19
approved a reduction in this factor to 4.0 for ductile materials only.
The Subcommittee on Design was continuing to study whether any
further reduction was warranted, and also whether a similar change
might be appropriate for non-ductile cast materials. Proof testing
may not be used if Section I has design rules for the component,
and in actual practice, such testing is seldom employed. However,
it can be a simple and effective way of establishing an acceptable
design pressure for unusual designs, odd shapes, or special features that would be difficult and costly to analyze, even with the
latest computer-based methods. A common application of proof
testing before the advent of sophisticated analytical methods was
in the design of marine boiler headers of D-shaped or square cross
section.
Tests that are used to establish the maximum allowable working
pressure of pressure parts must be witnessed and approved by the
AI, as required by Appendix A-22.10. The test report becomes a
permanent reference to justify the design of such parts should the
manufacturer want to use that design again for other boilers.
1.7.2.2 Design Loads. When Section I was written, its authors
understood so well that the internal working pressure of the boiler
was the design loading of overriding importance that virtually no
other loading was mentioned. To this day there is very little discussion of any other kind of loading, except for paragraph PG-22,
which cautions that this Section does not fully address additional
loadings other than those from working pressure and static head,
and provides no guidance regarding how to take such loads into
account, thus leaving it to the designer. Actually, internal pressure
is the principal loading of concern, and it appears in all Section
I design formulas. The pressure inside the boiler is called the
working pressure. For design purposes, Section I uses the term
Maximum Allowable Working Pressure, or MAWP, to define what
engineers usually understand to mean design pressure.
There are many other loads on a boiler in addition to pressure.
Among these are the weight of the boiler and its contents, seismic
loads, wind loads, and thermal loads. Section I has no provisions
specifically dealing with the last three, but it is the responsibility
of the designer to consider them. As boiler designs evolved over
the years, the manufacturers have recognized and made provisions
for these loads.
In recent years, more of the utilities’ base load, fossil-fired boilers
are increasingly being used in cyclic service, with frequent startups and shutdowns. Cyclic service also occurs with the increasing
use of HRSGs fired by combustion turbines. This type of operation
has the potential for causing repeated, relatively high transient thermal stress and may require careful analysis for fatigue and creep
damage. Although Section I has successfully considered creep and
creep rupture in setting allowable stresses, it has no specific rules
at this time for creep-fatigue interaction or even for simple fatigue
(see 1.8.7, Material Traceability). Nevertheless, designing against
fatigue, creep, and their interaction remains the responsibility of the
manufacturer. Elevated-temperature design for fatigue and creep is
a complex subject for which no complete rules have yet been developed. Such Code rules that are available appear in Section III,
Subsection NH, Class 1 Components in Elevated Temperature Service. Subsection NH is based on Code Case N-47, which dealt with
nuclear power plant components in elevated-temperature service
and whose earliest version dates back to the late 1960s. Elevatedtemperature service means service above that temperature when
creep effects become significant. This threshold is usually taken as
700°F (370°C) for many ferritic materials (carbon and low-alloy
materials) and 800°F (425°C) or higher for austenitic materials (the
high-alloy materials such as stainless steel). The allowable stress
tables in Section II Part D have notes indicating at what temperature
time dependent properties govern determination of the allowable
stress value. With the exception of parts of some superheaters, most
boilers are made of ferritic materials. Some manufacturers also use
fatigue rules from other international standards such as those contained in EN 12952, the European Standard for Water-tube boilers
and auxiliary installations.
1.7.2.3 Choice of Design Pressure and Temperature. Section
I does not tell the designer what the design pressure (MAWP) and
design temperature of a boiler should be. These design conditions
must be chosen by the manufacturer or specified by an architectengineer, user, or others. Section I requires only the MAWP to be
stamped on the boiler, not the design temperature. When discussing design temperature, it is necessary to distinguish between
metal temperatures and steam temperatures, either of which may
vary within the boiler. As a practical matter, the designer must
know and choose an appropriate design (metal) temperature for
each element of the boiler, because the allowable stress values are
based on these temperatures. In many cases, the design temperature of an individual element such as a superheater tube may be
much higher than the design steam temperature of the boiler. This
stems from the fact that the metal temperature of a heated tube is
always higher than that of the steam within and from the need to
provide a design margin for potential upsets in gas temperature or
steam flow.
In a natural-circulation boiler, most of the pressure parts are designed for the MAWP. However, slightly different design pressures
are used for some components, since paragraph PG-22 stipulates that
hydrostatic head shall be taken into account in determining the minimum thickness required “unless noted otherwise.” The formulas for
determining the thickness of cylindrical components under internal
pressure found in paragraph PG-27 are of two types: one described
as applicable to “tubing—up to and including 5 in. (125 mm) outside
diameter,” and the other applicable to “piping, drums, and headers.”
Having only these two categories of design formula sometimes puzzles inexperienced designers who are not sure which formula to use
for tubing larger than 5 in. (125 mm) outside diameter. They soon
learn the accepted practice for such tubing, which (by the process
of elimination) is to use the formula for “piping, drums, and headers.” Advice to this effect is stated in the first paragraph of PG-27.1
as follows: “… the equations under this paragraph shall be used to
determine the minimum required thickness or the maximum allowable working pressure of piping, tubes, drums, shells, and headers
in accordance with the appropriate dimensional categories as given
in PG-27.2.1, PG-27.2.2, and PG-27.2.3 …” The two types of wall
thickness formulas have other differences worth noting, as they are
a source of confusion to designers and have led to quite a number
of inquiries to The Committee on Power Boilers. See 1.7.2.6, Other
Factors Applicable to Tube and Pipe Design.
With the 2006 Addendum, Appendix A-317 CYLINDRICAL
COMPONENTS UNDER INTERNAL PRESSURE was added to
Section I. The designer may use the requirements of this appendix
to determine the minimum required thickness or the maximum allowable working pressure of piping, tubes, drums and headers in
place of the requirements of PG-27.
In the 2013 Addenda, the rules of Code Case 2664 were incorporated in Section I. These rules permit the design of components
that have multiple design conditions by considering the coincident
pressures and temperatures for boilers that operate through a range
of operating conditions. The case was originally written for HRSGs
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but when incorporated, it was made applicable to any boiler. A new
paragraph PG-21.4 is added specifically to address the design of
components with multiple design conditions. PG-21.4.2 provides
some useful definitions such as “Sustained conditions,” “Normal
operating conditions,” “Transient condition,” “Coincident pressure
and temperature,”: and “Start up and shut down.”
1.7.2.4 Design Stresses: Past, Present, and Future. The Section I
basis for determination of allowable stress is explained in Section II,
Part D, Mandatory Appendix 1, where the various safety factors,
or design factors, and quality factors applied to the various tensile,
yield, and creep strengths are presented in Table 1-100. See the chapter on Section II in this volume for further details.
The so-called safety factors, or design margins, now used in
establishing allowable stresses with respect to the various failure
modes, such as yielding or creep rupture, have evolved over the
life of the Code. Before World War II, the factor used on tensile
strength was 5. It was temporarily changed to 4 to save steel during
the war, and that change was made permanent around 1950. Starting in the late 1970s, the factor on yield strength was changed from
⅝ to ⅔, a change that was carried out over quite a long period. The
factor on the 100,000 hour creep rupture strength was formerly 0.6,
but around 1970, this was changed to the current factor of 0.67.
These reductions in design margins, or safety factors, were adopted
over time as improvements in technology permitted. These improvements included the development of newer and more reliable
methods of analysis, design, and non-destructive examination. The
imposition of quality control systems in 1973 and a record of long,
satisfactory experience also helped justify reducing some of the
design conservatism.
The factor on ultimate tensile strength was again reviewed in the
late 1990’s. It happens that this design factor is a significant one
because it controls the allowable stress for many ferritic (carbon
and low-alloy) steels below the creep range. However, the use of
a factor of 4 put users of the ASME Code at a disadvantage in
world markets, where competing designs are able to utilize higher
allowable stresses based just on yield strength. The inequity of this
situation caused the Code committees to reconsider the usefulness
and necessity of using a factor of 4 on tensile strength as one of
the criteria for setting allowable stress. In 1996, the Pressure Vessel Research Council (PVRC), a research group closely associated
with the code committees, was asked to determine whether the design factor on tensile strength could safely be reduced. The PVRC
prepared a report reviewing all the technological improvements in
boiler and pressure vessel construction that have occurred since the
early 1940s, which was when the design factor on tensile strength
was first reduced from 5 to 4. On the basis of that report’s favorable recommendation, the Committee decided, as an initial step, to
change the factor on tensile strength from about 4 to about 3.5 for
pressure vessels constructed under the provisions of Section VIII,
Division 1.
The Committee decided to make the same change for Section I
and, in 1997, established a task group to investigate the potential
effects of such a change and how best to implement it. That task
group concluded that Section I could safely join Section VIII in increasing its allowable stresses. The actual determination and publishing of new allowable stresses took the Committee some time,
because it was quite a task. To expedite the process while the Committee completed its work, new stresses for a limited group of materials were introduced by means of Code Cases, one for Section I
and two for Section VIII, since Code Cases can be issued far more
quickly than Code addenda. The three Cases were approved for
use in mid-1998. One problem with the new Cases was that some
jurisdictions were reluctant to accept them, or had no ready mechanism that would permit their prompt adoption. However, by 1999,
the Committee had completed its review and revision of stresses,
permitting incorporation of the new stress values into Section II,
Part D, in the 1999 addenda.
In the future, it is possible that the design factor on tensile
strength may be reduced further or eliminated altogether, depending on the results of these first steps and further studies. Note that
the change in design factor applied to tensile strength from ¼ to
1
/3.5 is a 14% change. However, few allowable stresses changed
that much, because the higher allowable stress may be determined
and controlled by the factor ⅔ applied to yield strength, rather than
tensile strength. Also note that the higher stresses are applicable
below the creep range only.
The above-described methods of setting maximum allowable
(design) stress values have been used by the Code committees
since the mid-1950s. During that time, new data have been obtained and analyzed to revise design stresses as appropriate, based
both on new laboratory tests and reported experience from equipment in service. There have been times when the analysis of new
data has resulted in a significant lowering of the allowable stresses
at elevated temperature. In all but a few instances, however, the
fine safety record of equipment built to the ASME Code has demonstrated the validity of the material data evaluation, design criteria, and design methods used.
1.7.2.5 Hydrostatic Head. The tubing design formula refers
to PG-27.4.9, which states that the hydrostatic head need not be
included when this formula is used. Thus, the design pressure, P,
is taken as just the MAWP for all tubes having a 5 in. and under
outside diameter. The additive term 0.005D in the tube design
formula was chosen by the Committee when the current version
of the tube design formula was adopted in the 1960s. The new
formula initially proposed at that time gave somewhat thinner
walls than the previous formula, leading to a concern on the part
of some Committee members that tubes for low-pressure boilers
would lack adequate strength to sustain any occasional mechanical loading to which they might be subjected. The 0.005D term
was a compromise value selected by the Committee in response
to this concern, an attempt to provide a little extra strength in the
tubes. No similar note excluding consideration of hydrostatic head
applies to the design formulas for piping, drums, and headers.
Accordingly, the design pressure, P, used in those formulas must
include the hydrostatic head, which on a large utility boiler could
add as much as 50 psi to the MAWP for a lower waterwall header
or a downcomer, since the height of such units may equal that of
a 15-story building. Of course, the additional hydrostatic head
would be much less for a header near the top of the boiler, such as
a roof-outlet header. Incidentally, traditionally the hydrostatic head
is measured from the elevation of the drum centerline, since that
is the normal waterline.
The exclusion of hydrostatic head in the tube-design formula
but not in the pipe-design formula came about from the adoption of slightly different formulas, which in one case (tubing) had
evolved for equipment of modest height, where hydrostatic head
was considered negligible, and in the other case (piping), where it
was thought necessary to include hydrostatic head. This arbitrarily
different treatment of hydrostatic head has little significance in
most practical instances. A much larger potential difference in wall
thickness for pipe versus tube results from a number of factors prescribed by PG-27 to account for the effects of expanding tubes,
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-21
threading pipe, or the need for structural stability, as described
next.
1.7.2.6 Other Factors Applicable to Tube and Pipe Design.
The first of these several factors is e, defined as a thickness factor for expanded tube ends, that is applied to tubes below certain
minimum sizes. PG-27.4.4 lists e values (f values from A-317.3(d)
when using A-317) required for various sizes of tubes. The thickness factor is an extra 0.04 in. (1.0 mm) thickness required over
“the length of the seat plus 1 in. (25 mm) for tubes expanded into
tube seats.” This provides a slightly heavier wall for that portion
of the tube that is rolled, or expanded, into the tube hole. In the
rolling process, the tube undergoes considerable cold-working and
some thinning, and the extra 40 mils (1.0 mm) wall thickness was
intended to ensure a sound joint no weaker than the unexpanded
portion of the tube. This extra 40 mils (1.0 mm) applies only to
very thin tubes, as stipulated in Note 4. Such tubes are usually used
only for very-low-pressure boilers.
Another of these factors is C, described as a “minimum allowance for threading and structural stability.” which is intended for
application to threaded pipes. Prior to the 2008a Addenda, this C
factor was also applied to non threaded pipe 3½ in. (89 mm) diameter and smaller for structural stability. This made the thickness
calculation for this size pipe very conservative compared to the
B31.1 calculation. When used as a threading allowance, C provides
extra wall thickness to make up for material lost in threading. Paragraph PG-27.4.3 and A-317.3(c) stipulate a C value of 0.065 in.
(1.65 mm) for pipe NPS ¾ (DN 20) and smaller, and a C value
equal to the depth of the thread for pipe larger than that. However,
PG-27.4.3 and A-317.3(c) make it very clear that the allowances
for threading and structural stability are not intended to provide for
conditions of misapplied external loads or for mechanical abuse.
1.7.2.7 Some Design Differences: Section I versus B31.1. As
explained in section 1.5 on the distinction between boiler proper
piping and boiler external piping, design rules for the latter are
found in the ASME B31.1 Power Piping Code. The formula for the
design of straight pipe under internal pressure in paragraph 104.1
of B31.1 looks the same as the design formula for piping, drums,
and headers in paragraph PG-27.2.2 of Section I, except that the
additive term C of Section I is called A by B31.1. In either case (A
or C), the intention is to account for material removed in threading, to provide some minimum level of mechanical strength and,
if needed, to provide an allowance for corrosion or erosion. There
are, however, some slight differences between Section I and B31.1
that should be mentioned, since occasionally designers forget that
certain piping, such as piping from the drum to water level indicators, or vent and drain piping, is boiler external piping for which
B31.1 rules apply. Paragraph 102.4.4 of B31.1 recommends an
increase in wall thickness where necessary for mechanical strength
or, alternatively, requires the use of design methods to reduce or
eliminate superimposed mechanical loading. Thus, B31.1 gives
the designer a choice: provide some (unspecified) increase in wall
thickness or take measures to limit mechanical loads. In Section I,
PG-22.1 states that the designer shall consider additional loading.
In either case, the details are left to the judgment of the designer.
According to 104.1.2(C) of B31.1, pipe used for service above certain pressures or temperatures must be at least a schedule 80 pipe.
This paragraph is similar to PG-27.4.5 of Section I. Another major
difference is that PG-27 allows the option of using the formulas in
A-317, B31.1 does not have a similar option. Also note that B31.1
has some very specific design requirements for certain types of
piping such as blowoff piping and feed water piping. For example,
ASME B31.1, paragraph 122.1.4 (A), requires the design pressure
of blowoff piping to exceed the maximum allowable working
pressure of the boiler by either 25 percent or 225 psi (1550 kPa),
whichever is less, but shall not be less than 100 psig [690 kPa
(gage)]. Also see Design Exercise No. 3, Choice of Feedwater
Stop Valve.
1.7.2.8 Bend Design. Another difference in the design of piping according to Section I versus B31.1 is in their respective
treatment of bends. Historically B31.1 paragraph 102.4.5 has
required that the minimum wall thickness at any point in a bend
not be less than that required for the equivalent straight pipe.
Ordinary bending methods usually result in some thinning of the
wall on the outside of bends and some thickening on the inside.
Consequently, under the B31.1 rule, a bend thinning allowance
must be added to the wall of a straight pipe so that the finished
bend will meet the required minimum thickness. Table 102.4.5 of
B31.1 provides recommendations for minimum thickness prior to
bending as a function of the radius of the pipe bend. If good shop
practices are followed, these allowances should result in bends
of the required minimum thickness. In the 2002 Addenda, B31.1
added a second method for determining the required thickness
of a bend, located in paragraph 102.4.5(B). The new equations
provided provide a method to calculate bend thickness, allowing a
certain level of thinning at the extrados of the bend but requiring a
certain thickening at the intrados of the bend. The user can choose
between the two methods. Section I does not have corresponding
rules, and over the years, quite a few inquiries have been received
regarding guidance on this subject. Before 1977, the Committee
responded to questions by a letter known as an informal reply, but
since January 1977, Committee responses have been published as
Interpretations (see section 1.3.2). Section I’s design approach to
bends, for both pipe and tube, is explained in Interpretation I-8323, a composite of earlier, informal replies. Because the acceptance of pipe or tube bends by the AI as meeting the rules of either
Section I or B31.1 is crucial to the timely completion of the boiler,
the designer should always be aware of which rules apply. Here is
Interpretation I-83-23:
Question: What rules does Section I impose with respect to
wall thinning and flattening of bends in boiler tubing?
Reply: Section I does not provide specific rules directly applicable to wall thinning and flattening of bends in boiler tubing.
However, the Subcommittee on Power Boilers intends that the
manufacturer shall select a combination of thickness and configuration such that the strength of the bend under internal
pressure will at least equal the minimum strength required for
the straight tube connected to the bend.
The Subcommittee on Power Boilers’ position, based on
many years of service experience, has been that thinning and
flattening of tube bends are permissible within limits established by the manufacturer, based upon proof testing.
To understand the reason for the difference in design approach
used by B31.1 and Section I for bends, remember that the Committee on Power Boilers has always recognized satisfactory experience as an acceptable basis for design. When the issue of the wall
thickness of tube and pipe bends was raised in the late 1960s, the
Committee had available a long record of satisfactory experience
to justify the design approach traditionally used for bends by the
1-22 t Chapter 1
major boiler manufacturers. There are, however, further arguments
to support such an approach. First, bends are components with two
directions of curvature, having inherently greater strength than
straight pipe, which has only one direction of curvature. Second,
a pipe bend resembles a portion of a torus. Membrane stresses in
a torus happen to be lower on the outside diameter than on the inside, so the change in wall thickness from bending a straight pipe
tends to put the material just where it is needed [this is the basis
for the bend calculation method in B31.1 paragraph 102.4.5(B)].
Third, the bending process usually increases the yield strength
of the metal by work hardening. Unless the bend is subsequently
annealed, it retains this extra strength in service. When bends are
proof tested to failure, they typically fail in the straight portion, not
in the bend, showing that the bend is stronger. This is the basis on
which Section I accepts them. It is also true that bends in Section I
tubes and pipe are more likely to be within the setting of the boiler,
where there is less chance that a bend failure would be dangerous
to people.
The Committee again addressed bends in a 2016 interpretation.
The Committee received an inquiry questioning whether a proof
test is the only way to design pipe and tube bends. The following Interpretation was published which offers the clarification that
proof test is just one of the methods (but not the only method) that
could be used to design per PG-16.1.
Question: Section I has design rules for straight tubes and
pipes, but no specific rules for the design of tubes or pipes
with bends. Shall PG-16.1 be used for the design of tubes or
pipes with bends?
Reply: Yes.
1.7.2.9 Corrosion/Erosion Allowance. PG-27.4.3 and A-317.3(c)
indicate that the design formulas do not include any allowance for
corrosion and/or erosion and that additional thickness should be
provided where they are expected. Thus, the designer is given the
responsibility for deciding whether such allowances are needed and,
if so, their amount and location.
Boiler manufacturers in the United States do not normally add
a corrosion or erosion allowance when calculating the design thickness of boiler pressure parts. Experience has shown such allowances
to be unnecessary under normal service conditions. Ordinarily, the
boiler water treatment controls oxygen levels, dissolved solids,
and pH so that corrosion on the waterside is insignificant. Similarly, fireside corrosion has not been a problem except under unusual circumstances attributable to certain temperature ranges and
some particularly corrosive constituents in the fuel. Even in these
cases, it is not usually practical to solve the problem by a corrosion
allowance. In the unusual circumstance of severe local corrosion
or erosion, any extra wall thickness allowance might at best serve
to prolong component life for only a short time. Furthermore, extra
thickness added to the wall of a heated tube raises the temperature
of the outside surface, thereby tending to increase the rate of corrosion. Some other solution to the problem is usually necessary, such
as elimination of the corrosive condition, a change in material, or
the provision of shielding against fly-ash erosion.
It is interesting to compare similar provisions for corrosion or
erosion found in Pressure Vessels, Section VIII of the ASME Code,
and in the Power Piping Code, B31.1. Section VIII provides similar but somewhat more specific guidance on corrosion and erosion
than Section I in paragraphs U-2(a)(1) and UG-25. Allowances for
corrosion or erosion are left to the designer’s judgment based on
information provided by the user of the vessel or the user’s agent.
Section VIII also states that extra material provided for this purpose need not be of the same thickness for all parts of the vessel if
different rates of attack are expected for the various parts. Finally,
Section VIII provides that no additional thickness needs to be provided when previous experience in like service shows that corrosion does not occur or is of only a superficial nature.
The Power Piping Code, B31.1, 102.4, requires a corrosion or
erosion allowance only when corrosion or erosion is expected and
in accordance with the designer’s judgment. Thus, the same general approach to corrosion and erosion is seen in Section I, Section
VIII, and B31.1.
1.7.2.10 Weld Joint Strength Reduction Factor. As mentioned in 1.7.4, Welding and Postweld Heat Treatment, welds have
been assumed to be equivalent to the base material it joins. A manufacturer noted that B31.1 permitted the use of fusion welded pipe
(with filler metal added) while Section I did not permit the use of
welded pipe. They then noted that there was nothing in Section
I that would prohibit them from rolling plate into a cylinder,
welding a long seam, and using as a boiler part. The Committee
then chartered a Task Group with members from the Boiler and
Pressure Vessel Code committees as well as B31 Piping committees to review the issue and develop technically equivalent rules
that would be implemented in Section I, B31.1, and B31.3. The
result of this effort was the addition of PG-26 Weld Joint Strength
Reduction Factor in the 2008a Addenda.
As noted in PG-26, these reduction factors apply to longitudinal
butt welds (which includes spiral or helical welds) and to hemispherical heads or any other spherical sections that comprise segments joined by welding. It then goes on to caution the designer
that they are responsible for determining the applicability of weld
joint strength reduction factors to other welds. Note that the weld
strength reduction factor is not applicable to any material that has
a maximum design temperature of 800°F (425°C) or less (may be
higher for some materials). Also, note that PG-26 and Table PG26 are not applicable to carbon steel pipe and tubes (Note 3 of the
table). The terminology of weld strength reduction factor can be
a little misleading to some as it is really a strength factor, not a
strength reduction factor. For example, when Table PG-26 shows a
factor of 0.7 for a given condition, the user multiplies the allowable
stress (or strength) by this factor, reducing it by 30%, not by 70%.
B31.1 Power Piping and B31.3 Process Piping Code also address weld strength reduction factors in paragraphs 102.4.7 and
302.3.5 respectively. The B31.3 approach is somewhat different
in that it also provides a procedure (see paragraph 302.3.5(f) and
Note 9 of Table 302.3.5) to calculate the weld joint strength reduction factors for materials for which the Table doesn’t explicitly list
the reduction factors. Section I, doesn’t have the same provision
and hence in 2015 Edition weld strength reduction factors of few
Nickel Base Alloys were added to Table PG-26 which now permits
the usage of Nickel Base alloys fabricated with longitudinal and
spiral (helical) seam welds in the creep range.
1.7.3
Fabrication
Fabrication is not specifically defined in Section I, but it is generally understood to mean all those activities by which the manufacturer converts material (plate, tube, pipe, etc.) into completed
boiler components. Such activities include welding, bending,
forming, rolling, cutting, machining, punching, drilling, broaching,
reaming, and others. Section I permits the manufacturer very broad
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-23
latitude in fabrication because of the wide variations in manufacturing practice, machinery, and trade methods.
Section I provides only a limited number of general rules for
fabrication in PG-75 through PG-82. (Welding is covered extensively in Part PW, and a brief discussion of those rules is given
next, in section 1.7.4, Welding and Postweld Heat Treatment.) The
general rules in Part PG specify tolerances for drums and ellipsoidal heads, and limit certain cutting, drilling, and punching processes so that subsequent machining will remove all metal with
mechanical and metallurgical properties that have been affected by
the earlier process.
The manufacturer is permitted to repair defects in material if
acceptance of the AI is first obtained for both the method and the
extent of repairs.
1.7.3.1 Cold Forming of Austenitic Materials. Older Editions
of Section II, Part D used to contain a caution which stated in part:
“Cold forming operations performed during manufacture of austenitic stainless steel pressure parts may cause impaired service performance when the component operates in the creep range [above
1000°F (540°C)]. Heat treatment after cold forming at temperature
given in the material specification will restore the intended properties of the material and will minimize the threat of premature
failure due to recrystallization during the time of operation.”
For this reason Section I introduced PG-19 COLD FORMING
OF AUSTENITIC MATERIALS with the 1999 Addendum. For
cold bending operations Section I permit’s exemption from the
post cold-forming heat treatment requirements when the forming
strains are less than the proscribed maximum strain limits in Table
PG-19. However, PG-19.2 requires heat treatment in accordance
with Table PG-19 for flares, swages and upsets regardless of the
amount of strain.
PG-19 includes the formulas for calculating the forming strain in
cylinders, spherical or dished heads, pipes and tubes, Table PG-19
currently (2015 Edition) lists 28 austenitic or nickel based materials permitted by Section I which may be subject to post coldforming heat treatment.
1.7.3.2 Cold Forming of Creep Strength Enhanced Ferritic
Steels. Similar to the concerns with cold forming austenitic materials (see 1.7.3.1, Cold Forming of Austenitic Materials), testing
of creep strength enhanced ferritic steels has shown that cold
forming can have an adverse effect on the long term creep properties of the materials. To address this, the Committee added PG-20
Cold Forming of Creep Strength Enhanced Ferritic Steels (CSEF)
to the 2010 Edition. This provides heat treatment requirements
for cold formed material based on material grade, level of strain,
and design temperature of the material. The 2010 Edition initially
included grades 91 and 92 but this was later changed in the 2013
Edition by removing grade 92. Grade 92 was still a code case
material and the cold forming requirements were moved to the
associated code case (2179). Cold forming rules for other CSEF
steels have been included in their associated code cases.
1.7.4
Welding and Postweld Heat Treatment
An important factor in the evolution of today’s efficient highpressure boilers was the development of welding as a replacement for the riveted construction used in the 19th and first half
of the 20th centuries. The ASME has recognized the importance
of welding by instituting Section IX (Welding and Brazing Qualifications, first published as a separate Code section in 1941) and
including special welding rules in each of the book sections covering boilers or pressure vessels. The reader is also directed to the
separate chapter on Section IX in this volume for further information on welding. Section I rules for welding are found in Part PW
(Requirements for Boilers Fabricated by Welding), which refers
to Section IX for qualification of weld procedures and welder performance and, in addition, provides rules specifically applicable
to boilers and their components, including boiler proper piping.
The rules for the welding of boiler external piping (as opposed to
boiler proper piping) are not found in Section I; they are found in
B31.1, Power Piping (see 1.5, Distinction Between Boiler Proper
Piping and Boiler External Piping). Power Piping also invokes
Section IX for the qualification of weld procedures and welder
performance, but is some-what more liberal with respect to the
transfer of procedures and welders from one organization to
another.
Among the many aspects of welding covered by Part PW are
the following: responsibilities of the manufacturer or other organization doing the welding; the materials that may be welded; the
design of welded joints; radiographic and ultrasonic examination
of welds and when such examination is required; the welding of
nozzles; attachment welds; welding processes permitted; qualification of welding; preparation, alignment, and assembly of parts
to be joined; the use of backing strips; advice on preheating; requirements for postweld heat treatment; repair of weld defects;
exemptions from radiography; the design of circumferential joints;
the design of lug attachments to tubes; duties of the AI related to
welding; acceptance standards for the radiography and ultrasonic
examination required by Section I; preparation of test plates for
tension and bend tests; and welding of attachments after the hydrostatic test. Some of these topics are discussed here.
An important aspect of welding, compared to some of the other
means of construction, is the absolute need for careful control of
the welding process to achieve sound welds. The ASME Code attempts to achieve this control by allowing welds to be made only
by qualified welders using qualified procedures. Section IX provides the rules by which the welders and the weld procedures may
be qualified. However, there are many other aspects of welded construction besides qualification, and rules covering these other aspects are found in the other ASME book sections covering welded
construction (Sections I, III, IV, and VIII).
The ultimate goal of welding procedure and performance qualification is to achieve a weldment with properties that are at least
the equivalent of the base material being joined, as demonstrated
by certain tests. Qualification of the procedure establishes that
the weldment will have the necessary strength and ductility when
it is welded by an experienced welder following that procedure.
Qualification of the welder establishes that he or she can deposit
sound weld metal in the positions and joints to be used in production welding.
An assumption implicit in the welding rules of Section I is that
a weld is the equivalent of the base material it joins; accordingly,
a properly made weld does not weaken the vessel. Consequently,
there is no bar to superimposing attachments on welds or having
nozzles or other openings placed where they intersect welds (this
is stated explicitly in PW-14). There is also no rule that would
prevent a manufacturer from making an opening for a nozzle in
a vessel, then deciding the nozzle isn’t needed, and replacing the
material removed for the opening with a properly designed and
welded patch. This position changed to some degree with the addition of PG-26 Weld Joint Strength Reduction Factor in the 2008a
Addenda (see 1.7.2.10, Weld Joint Strength Reduction Factor).
1-24 t Chapter 1
1.7.4.1 Qualification of Welding Procedures. It is a general
rule under any Section of the ASME Boiler and Pressure Vessel
Code and the ASME Code for Pressure Piping, B31, that all welding must be done by qualified welders using qualified welding
procedures. With some rare exceptions, every manufacturer (or
other organization doing the welding, such as an assembler or
parts manufacturer) is responsible for the welding it does and is
also responsible for conducting the tests required by Section IX
to qualify the welding procedures used and the performance of
the welders who apply those procedures. The manufacturer does
this by preparing certain documentation, known as a Welding
Procedure Specification (WPS) and a Procedure Qualification
Record (PQR) that documents and supports the WPS. The WPS
comprises a set of instructions, primarily for the welder (but also
for the Authorized Inspector), regarding how to make a production weld to Code requirements. These instructions are written in
terms of certain welding parameters that are called essential, nonessential, and, when required, supplemental essential variables
(see below).
The Procedure Qualification Record (PQR) is a formal record
of the welding data (the actual value of the variables recorded
during the welding of the test coupons) for each welding process
used and the results of mechanical test specimens cut from the test
coupons. Non-essential variables used during the welding of the
test coupon may be recorded at the manufacturer’s option. The tests
(usually tensile and bend tests) are used to demonstrate that a weldment made using the WPS has the required strength and ductility
for its intended application. Various other tests are sometimes used
instead of the bend and tensile tests. All of these tests are more fully
explained in Section IX. The variables used in production welding
may vary somewhat from those used during the welding of the test
coupons. Note that the purpose of the Procedure Qualification test
is just to establish the properties of the weldment and not the skill
of the welder, although it is presupposed that the welder performing
the procedure qualification test is a skilled worker.
With the 2000 addenda, all book sections of the ASME Code began to permit the use of a number of ANSI/AWS Standard Welding
Procedure Specifications (SWPS) as an alternative to requiring the
manufacturer or contractor to qualify its own procedures. Requirements were added to ensure that each manufacturer would have
some experience with standard welding procedures before using
them. The standard procedures accepted are listed in Section IX,
Appendix E. Paragraph PW-1.2 and Appendix paragraph A-302.7
of Section I advise that the use of Standard Welding Procedure
Specifications is acceptable, provided the welding meets the additional requirements of Section I. Section IX simultaneously
added a new Article V, Standard Welding Procedure Specifications, which provides details and restrictions on the use of standard
welding procedures. The Code Committee wanted to make sure
that any organization using an SWPS would first establish its competence with respect to key aspects of the welding. To that end, an
employee of the manufacturer or contractor must sign and date the
SWPS, as evidence that the organization is acknowledging responsibility for its use. With some exceptions, the organization must
then demonstrate its ability to control welding using an SWPS by
welding and testing one groove weld coupon, and must record detailed information about the welding variables used (see below).
For further details on the use of SWPS, see the chapter in this volume on Section IX.
1.7.4.2 Qualification of Welder Performance. To complete the
qualification process for welded construction, performance tests
must be conducted for each welder to establish the welder’s ability
to deposit sound weld metal. In general, this welder performance
qualification is accomplished by mechanical bend tests of performance test coupons, radiography of a test coupon, or radiography
of the welder’s initial production weld. When welders are qualified,
identification marks are assigned to them so that all welded joints
can be identified by the identity of the person who made them.
For various reasons, performance qualification tests do not
qualify welders to weld for other manufacturers or contractors,
except in the case of similar welding work on piping using the
same procedure. Among the reasons for this prohibition is a desire
to ensure that each manufacturer will take full responsibility for
welding done by his or her organization. The Committee apparently believed that requiring performance qualification for each
new employer would achieve better results than a system that permits one manufacturer to rely on performance testing supposedly
carried out by another organization. Some manufacturers share a
related view; if they are to be held responsible for their welding,
they want to conduct their own welder performance qualifications
rather than relying on others.
1.7.4.3 Welding Variables. In the development of the WPS, it
is necessary to establish which variables of the welding process
are so-called essential variables in the production of qualifying
welds and those that are not (non-essential variables). An essential
variable is one that, if changed, would affect the properties of
the weldment and thus require requalification of the procedure,
that is, additional testing and issuance of a new PQR to support
the changed WPS. A non-essential variable for a weld procedure
is one that can be changed without requiring requalification,
although it would require a change in the WPS. Essential variables for weld procedures include material thickness, P-Number
(which refers to material category; see below), filler metal alloy,
the use or omission of backing, and the use or omission of preheat
or postweld heat treatment. Examples of nonessential variables for
procedure qualification are groove design, root spacing, method of
back gouging or cleaning, change in electrode size, and the addition of other welding positions to any already qualified.
Variables may be categorized differently, depending on whether
they are applied to weld procedure or welder performance qualification. For example, the addition of other welding positions to any
already qualified is an essential one for performance, since welding in a new position, such as vertical instead of horizontal, could
certainly affect the ability of the welder to deposit a sound weld.
However, it is a nonessential variable for procedure qualification
because qualifying the procedure demonstrates the properties of
the weldment, not the skill of the welder or welding operator. Such
a welder would presumably deposit sound metal in any position,
and the properties of the resulting weldment would be unaffected.
Section IX has a great number of tables summarizing procedure
and performance variables for all common welding processes.
1.7.4.4 Material Categories (P-Numbers). One important essential variable is the type of base material being welded. There are
several hundred different materials permitted for Code construction
by the various book sections. If every change in base material meant
that weld procedure specifications and welder performance had to
be requalified, the qualification of procedures and welders for all
these materials would be an enormous task. To reduce this task to
manageable proportions, the ASME has adopted a classification
system in which material specifications are grouped into categories,
based on similar characteristics such as composition, weldability, and
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-25
mechanical properties. Each category is defined by a P-Number.
Within the P-Number category are sub-categories called Group
Numbers for ferrous base metals that have specified impact requirements. Although Section I does not use Group Numbers in relation
to impact testing, it does sometimes establish different postweld heat
treatment requirements for the different Group Numbers within a
given P-Number category. A numerical listing of P-Numbers and
Group Numbers can be found for all Section II materials, by specification number, in Table QW/QB-422 of Section IX.
A welding procedure that has been qualified for a particular base
material may be used for any other base material with the same
P-Number. (On the other hand, if a base material has not been assigned a P-Number, it requires an individual procedure qualification.) Similarly, a welder who has been qualified for a base metal
of a particular P-Number may be qualified for quite a few other
P-Number base materials (see QW-423).
QW-423.2 permits assigning a P- or S- Number to materials conforming to national or International Standards or Specifications,
providing the material meets the mechanical and chemical requirements of the assigned material.
Welding filler metals (electrode, bare wire, cored wire, etc.) are
categorized by F-Number in Table QW-432 of Section IX. Part C
of Section II lists American Welding Society filler metal specifications that have been adopted by the ASME and designated as SFA
specifications.
Although a specific definition of each P-Number in terms of
chemical composition is not given in the code, the P-Number categories for commonly used Section I materials are as follows:
t P-No. 1 covers plain carbon steels, C–Mn–Si, C–Mn, and
C–Si steels.
t P-No. 3 covers low-alloy steels obtained by additions of up to
5/4% of Mn, Ni, Mo, Cr, or combinations of these elements.
t P-No. 4 alloys have higher additions of Cr or Mo or some Ni
to a maximum of 2% Cr.
t P-No. 5 covers a broad range of alloys varying from 2.25 Cr-1
Mo to 9 Cr-1 Mo. This category is divided into three groupings: 5A, 5B, and 5C. The 5A grouping covers alloys up to 3%
Cr; 5B covers alloys with from 3% to 9% Cr; and 5C covers
alloys with strength that has been improved by heat treatment.
t P-No.15 covers a class of materials referred to as creep
strength ferritic steels (CSEF). This category is further broken
down into six groups designated 15A through 15F. Currently
(2016), only 15E has any materials assigned to it, Grade 91
(9Cr-1Mo-V) and Grade 92 (9Cr-2W).
t P-No. 6 covers 12-15% Cr. Ferritic Stainless Steels including
Types 403, 410, and 429.
t P-No. 7 covers 11-18% Cr. Ferritic Stainless Steels including
Types 405, 409, 410s, and 430.
t P-No. 8 covers the austenitic stainless steels.
1.7.4.5 Weldability. Materials are said to have good weldability if they can be successfully joined, if cracking resulting from
the welding process can be avoided, and if welds with approximately the same mechanical properties as the base material can be
achieved. PW-5.2 prohibits welding or thermal cutting of carbon
or alloy steel with a carbon content of over 0.35%. Higher carbon
can cause zones of high hardness that impart adverse properties to the weld and heat-affected zone (HAZ) and may increase
susceptibility to cracking, for regions of high hardness often lack
ductility. In fact, carbon strongly affects weldability because of its
influence on hardenability during heat treatment. Heat treatment
includes not only deliberate heat treatment such as solution annealing, but also the thermal cycle that the weld and HAZ undergo in
the welding process.
Various expressions, known as carbon equivalency (CE) formulas, have been developed to predict a steel’s hardenability by heat
treatment. Thus they have also proven to be rough indicators of the
relative weldability of steels, their susceptibility to cracking during
welding, and the need for preheat to prevent cracking during or
after welding. This type of cracking is variously described as cold
cracking, hydrogen cracking, and delayed cracking (because it
may occur some hours after welding is completed). ASME Boiler
and Pressure Vessel Code—Section I has adopted the following
version of Carbon Equivalent (CE) in Table PW-39.1:
CE = C + (Mn + Si)/6 + (Cr + Mo + V)/5 + (Ni + Cu)/15
Note: If the chemistry values of the last two terms are not available, 0.15% shall be substituted as follows:
CE = C + (Mn + Si)/6 + 0.15
Thus carbon equivalency (CE) is the sum of weighted alloy
contents, where the concentration of alloying elements is given in
weight percent. From this equation, it is seen that carbon is indeed
the most potent element affecting weldability. The formula also
shows the relative influence of other elements that might be present in pressure vessel steels, compared to that of carbon.
Associated with the various carbon equivalency formulas are
weldability guidelines. A certain value of carbon equivalency, perhaps 0.35% or less, might indicate good weldability; a higher value
might indicate that preheat and/or postweld heat treatment are required to avoid excessive hardness and potential cracking in the
welds; and a still higher value might mean that the material is very
difficult to weld and both high preheat and postweld heat treatment
will be needed to obtain satisfactory welds. The maximum permitted CE for the application in Section I is 0.45%. However to use
this exemption in Section I, a minimum preheat of 250°F (120°C)
is required and no individual weld pass may exceed ¼ inch (6 mm).
The same carbon equivalency formula as shown above is given in
the supplementary (nonmandatory) requirements of ASME Specifications SA-105 and SA-106. For SA-105 forgings, the carbon
equivalent is limited to 0.47 or 0.48, depending on thickness; for
SA-106 pipe, the limit is 0.50. There would be little likelihood of
making successful welds in these materials with CE values higher
than those limits, even with high preheat.
Although various carbon equivalency formulas have been developed over the years for specific alloys, no universal formula has
been devised that works well for all the low-alloy steels. In fact the
more complex the alloy becomes, the more difficult it is to devise
an equivalency formula. More recent formulas for low-alloy steels
involve more complex interactive terms rather than the simple additive terms of the formula cited above.
1.7.4.6 Bending Stress on Welds. Most of the design formulas in
both Section I and Section VIII are based on the use of membrane
stress as the basis for design. In a boiler, the tubes, the piping, the
headers, and the shell of the drum are all designed for the membrane
stress in their cylindrical walls. Bending stress and the effects of
stress concentration are not calculated, although they are known to
be present to some extent. This is explained not in Section I, but
in UG-23(c) of Section VIII. In fact, there are bending stresses in
such pressure vessel components as flat heads, stayed heads, dished
heads, hemispherical heads, and cylinder-to-cylinder junctions.
1-26 t Chapter 1
In recognition of the existence of these largely unavoidable bending stresses, and perhaps still reflecting some lack of confidence in
the soundness of welded construction, Section I contains a number of
design rules intended to minimize bending stresses on welded joints.
For instance, PW-9.3 provides requirements for transitions at butt
welds between materials of unequal thickness. For circumferential
welds in tube and pipe components, the transition shall not exceed
a slope of 30 degrees from the smaller to larger diameter. For welds
in shells, drums, and vessels or welds attaching heads to shells, a
gradual taper, no greater than 1 : 3, is required. A 1 : 3 slope, or taper,
represents an angle of a little over 18 degrees. This paragraph was
revised in the 2015 Edition to include a new figure (see Figure PW9.3.3) to illustrate how the transition may be made between heads
and shells. For each of these transitions, the weld may be partly or
entirely in the transition or may be adjacent to the transition.
Long after these rules were formulated, finite element analyses
have demonstrated their validity. That is, the discontinuity stresses
developed at these gradual changes in thickness have generally
been found to be unremarkable and well within the limits that
would apply if the design-by-analysis methods of Section VIII, Division 2, were to be applied.
For decades, paragraph PW-9.4 had prohibited construction in
which bending stresses were “brought directly on a welded joint.”
This paragraph had also specifically prohibited a single-welded
butt joint if the joint would be subject to bending stress at the root
of the weld, as illustrated in Figure PW-9.2. In 1996, the Committee recognized that bending stresses routinely occur on welded
joints in all boilers and pressure vessels with no untoward results
and that this broad prohibition against bending stresses was unwarranted. Accordingly, the general prohibition against subjecting
weld joints to bending stress was deleted, and PW-9.4 was revised
so that it now prohibits only the single-welded corner joints illustrated in Figure PW-9.4.
1.7.4.7 Attachment Welds. Section I provides requirements for
attachment welds attaching nozzles and other connections to shells,
drums, and headers. The accompanying figure, Figure PW-16.1,
illustrates some acceptable nozzles and connections and provides
requirements for minim weld sizes. With the exception of illustrations (z-1) and (z-2), these illustrations all define the minimum
weld sizes in a plane through the nozzle parallel to the longitudinal
axis of the shell with no guidance on the profile the around the rest
of the circumference of the nozzle. With no guidance given, most
users took this to mean that the same minimum weld size should
be maintained around the circumference of the nozzle. This works
well for nozzles with an outside diameter up to about half the diameter of the shell but becomes difficult as the nozzle size increases.
This was addressed in the 2010 Edition with the addition of a new
paragraph, PW-16.7, which provided requirements for weld sizes
around the circumference of the nozzle.
For welded connections such as nozzles, Section I requires sufficient weld on either side of the connection to develop the strength
of any non-integral reinforcement (compensation) through shear
or tension in the weld. The allowable stress values for weld metal
are a function of the type of weld and loading, varying from 49%
to 74% of the allowable stress for the vessel material. Figure PW15 Examples of Weld Strength Calculations illustrates how the required weld strength (see PG-37.2) may be calculated.
Weld strength calculations for nozzle attachments are not required (PW-15.1.6) for certain configurations shown in Figure
PW-16.1. For these connections, the welds still have to satisfy the
minimum weld sizes shown in Figure PW-16.1.
1.7.4.8 Some Acceptance Criteria for Welds. Part PW includes
fabrication rules covering welding processes, base metal preparation, assembly, alignment tolerances, and the amount of excess
weld that may be left on the weld joint (so-called reinforcement).
In general, butt welds in pressure-containing parts must have complete penetration, and the weld groove must be completely filled.
To ensure that it is filled and that the surface of the weld metal is
not below the surface of the adjoining base metal, extra weld metal
may be added as reinforcement on each face of the weld. A table
in PW-35 gives the maximum amount of reinforcement permitted,
as a function of nominal thickness and whether the weld is circumferential or longitudinal. Requirements for butt welds are found in
PW-9, PW-35, and PW-41.2.2. PW-9 and PW-35 stipulate that butt
welds must have full penetration. PW-41.2.2 adds that complete
penetration at the root is required for single-welded butt joints
and that this is to be demonstrated by the qualification of the weld
procedure. Lack of penetration is a reason for rejection of welds
requiring volumetric examination. PW-35.1 limits undercuts to the
lesser of 1/32 in. (0.8 mm) or 10% of the wall thickness, and they
may not encroach on the required wall thickness. Some concavity
in the weld metal is permitted at the root of a single-welded butt
joint if it does not exceed the lesser of 3/32 in. (2.5 mm) or 20% of
the thinner of the two sections being joined. When concavity is permitted, its contour must be smooth, and the resulting thickness of
the weld, including any reinforcement on the outside, must not be
less than the required thickness of the thinner section being joined.
1.7.4.9 Preheating. Deposited weld metal is cooled very
quickly by its surroundings. Once it solidifies, it forms various
microstructural phases—solid solutions of iron and carbon (and
other alloying elements). These phases include ferrite, pearlite,
bainite, martensite, and austenite (in the higher alloy materials).
The formation of any particular phase depends on the cooling
rate and alloying elements such as chrome or nickel that may be
present. Certain phases, such as untempered martensite or bainite,
can impart unfavorable properties (e.g., high hardness, lack of
ductility, and lack of fracture toughness) to the resulting weldment.
One way to address this problem is through the use of preheating,
which, by raising the temperature of the surrounding base metal,
slows the cooling of the weld and may prevent the formation of
undesirable phases.
Preheat serves another useful function: It helps to ensure that
the weld joint is free of any moisture, which can otherwise serve
as a source of hydrogen contamination in the weld. Hydrogen can
dissolve in liquid weld metal and by various mechanisms can cause
cracking in the weld (known variously as cold cracking, hydrogenassisted cracking, and delayed cracking). Maintaining the weldment at preheat temperature during and after welding promotes the
evolution of dissolved hydrogen.
Although preheating a weld joint can be beneficial, Section I
does not mandate the use of preheat, except as a condition for the
omission of postweld heat treatment (as provided in Table PW39).
However, it is often specified for new construction welding and
for repair welding, especially when the walls are relatively thick.
A brief guide to preheating practices is included in Nonmandatory
Appendix A-100.
1.7.4.10 Postweld Heat Treatment. As explained under
preheating, rapidly cooling weld metal and the adjacent heataffected zone are subject to the formation of adverse phases that
can result in zones of high hardness, lack of ductility, and poor
fracture toughness in the weldment. In addition, the differential
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cooling of the weld metal compared to the surrounding base metal
can lead to the formation of very high residual stresses. Again,
the extent to which any of these effects take place is a function
of the cooling rate, alloy composition, relative thickness of the
parts being joined, and whether preheat is applied. Experience
has shown that preheating and postweld heat treatment (PWHT)
are often unnecessary for relatively thin weldments, especially
those of plain carbon steel. However, the general rule imparted
in paragraph PW-39 is that all welded pressure parts of power
boilers must be given a postweld heat treatment unless otherwise
specifically exempted—for example, by PFT-29 for staybolts
or PMB-9 for miniature boilers, or by the notes in the tables in
PW-39. The materials in Table PW-39 are listed in accordance
with the P-Number grouping of Table QW/QB-422 of Section
IX. See Section 1.7.4.4, Material Categories (P-Numbers), above
for details.
While preheating is aimed at preventing or limiting the formation of adverse phases, postweld heat treatment is used to ameliorate their effects. Postweld heat treatment is capable of tempering
or softening hard phases, and it can restore a large measure of ductility and fracture toughness in the weld and heat-affected zone. At
the same time, it relieves the residual stress caused by the cooling
of the weld metal. The goal of PWHT, therefore, is to restore the
properties of the weldment as nearly as possible to those of the
original base metal.
In PWHT the components to be treated are slowly heated
(either in a furnace or locally) to the temperature specified in
Table PW-39. They are held at that temperature for the time
specified, usually 1 hr/in. (1 hr/25 mm) of thickness plus an additional 15 min/in. (15 min/25 mm) over a certain thickness. This
is intended to ensure that the centermost portions of thick sections
have sufficient time to reach the minimum holding temperature.
The nominal thickness in Table PW-39 used to determine PWHT
requirements is the thickness of the weld, the pressure-retaining
material, or the thinner of the sections being joined, whichever is
the least. The time-at-temperature requirement can be satisfied by
an accumulation of postweld heat treatment cycles. When it is impractical to heat treat at the specified temperature, it is permissible
to heat treat at lower temperatures for longer periods of time, but
only for P-No. 1 and P-No. 3 materials. Table PW-39.1 lists these
alternative longer times and shows that for a 50°F (28°C) decrease
in the minimum specified holding temperature, the holding time
doubles. This shows how strongly temperature-dependent the underlying creep relaxation process is.
As mentioned above, the tables in PW-39 which provide exemptions to PWHT are arranged by P-Number. Within those tables,
the exemptions are then based on things like type of weld (e.g.
circumferential butt weld, fillet weld, combination groove and
fillet, weld overlay, etc.), thickness of weld, weld process, level
of preheat, etc. There have been a series of revisions to the table
for P-No. 1 materials, starting with the 2009b Addenda, to greatly
simplify the exemptions. In the 2009b Addenda, two new general
notes were added, (a)(1) and (a)(2) which exempted some welds
based on thickness and preheat and in the case of (a) (2), also weld
pass size and carbon equivalency. These new exemptions applied
to welds up to ¾ in (19 mm) thick for note (a)(1) and up to 1½ in
(38 mm) thick for note (a)(2). This is a departure from previous addenda as these exemptions do not depend on the type of weld, that
is, they apply equally whether a butt weld, fillet weld, combination
groove and fillet etc. The table was further simplified in the 2011a
Addenda by eliminating nine notes, all of which were now covered
by notes (a)(1) and (a)(2).
Unlike some other book sections, Section I does not specify any
particular heating or cooling rate to be used in PWHT. PW-39.3
stipulates only that the weldment shall be heated slowly to the required holding temperature. It goes on to say that after being held
at that temperature for the specified time, the weldment shall be allowed to cool slowly in a still atmosphere to a temperature of 800°F
(425°C) or less. This is to avoid high thermal stresses and potential distortion caused by large differential temperatures throughout
the component. Over time, many manufacturers have developed
their own requirements for heating and cooling rates and these may
vary based on the material grade, component arrangement, and/or
heat treatment method. To provide guidance for manufacturers in
developing their procedures, a new paragraph, A-101, was added
to Nonmandatory Appendix A, containing suggested heating and
cooling rates.
The subject of welding and postweld heat treatment is a complex
one. For further guidance, see the chapter on Section IX in this
volume.
1.7.5
Brazing Rules
Although brazing had long been used in construction of certain
low pressure boilers, prior to the 1996 Addenda, no brazing rules
had ever been provided in Section I. Thus Part PB brazing rules
resemble the Part PW welding rules, but are much less extensive.
One notable difference is that the maximum design temperature is
dependent on the brazing filler metal used and base metals being
joined. Brazing procedures and the performance of brazers must
be qualified in accordance with Section IX by methods similar to
those used for qualifying weld procedures and welders. The design approach used for determining the strength of brazed joints is
given: the manufacturer must determine from suitable tests or from
experience that the specific brazing filler metal selected can provide a joint which will have adequate strength at design temperature. The strength of the brazed joint may not be less than that of
the base metals being joined. This strength is normally established
by the qualification of the brazing procedure. Some acceptable
types of brazed joints are illustrated and Part PB provides guidance
on inspection and any necessary repairs. Nondestructive examination of brazed construction relies primarily on visual examination
supplemented by dye penetrant inspection if necessary.
1.7.6
Riveting Rules
As indicated in 1.3.1.3, Part PR, the 2013 Edition was the first
time riveting rules had been published since the 1971 Edition.
Some of the riveting information in the 2013 Edition is a direct
copy from the 1971 Edition but there were also some significant
updates. For example, the new Mandatory Appendix V, Additional
Rules for Boilers Fabricated by Riveting, is a consolidation of information about riveting that was scattered through the 1971 Edition in parts PG, PFT, and PWT while the information in PR-2 and
PR-23 are new requirements.
Riveting, like welding and brazing, requires a certain level of
skill and experience but unlike those methods, the use of riveting
is not as widespread so an experienced workforce is not as readily available. To recognize this, the Committee added PR-2 which
states that the Manufacturer is responsible for all riveting but provides conditions under which they may use individual riveters that
are not under their direct employment.
To ensure proper riveting while avoiding burdening the
Manufacturer with requirements to qualify riveters and riveting
procedures, the committee decided to instead place limits on certain riveting variables. This includes using a factor of safety of 5
1-28 t Chapter 1
in lieu of 3.5 (PR-8.2 multiplies the allowable stress value by 0.7),
limiting the maximum rivet hole size (PR-21.1), and the additional
requirements on the riveting process itself in the new PR-23 (such
as the temperature of the rivet before driving).
Another important rule, or actually removal of a 1971 allowance, is related to lap joint construction. In the 1971 Edition, PR16.2 permitted the use of lap joint construction for longitudinal
seams in shells and drums which did not exceed 36 inches in diameter with an MAWP ≤ 100 psig. The Committee felt that this was
an inferior construction so have deleted this allowance when developing the 2013 Edition so now all drum long seams fabricated
by riveting must be of butt- and double-strap construction (PR-10).
1.7.7
Nondestructive Examination
There are several related terms applied to Code construction
that are somewhat imprecisely used. These are examination, inspection, and testing. Within the context of Section I, examination usually describes activities of the manufacturer; inspection
refers to what the Authorized Inspector does; and testing refers
to a variety of activities, usually performed by the manufacturer.
Some confusion arises from the fact that nondestructive examination (NDE) includes activities defined as examinations but which
are often called tests. NDE is an indispensable means of ensuring
sound construction because, when properly used, these examinations are capable of discovering hidden flaws in material or welds.
The examinations referenced by Section I in the NDE category
are the following: radiographic examination, ultrasonic examination, magnetic-particle examination, and liquid-penetrant examination (also called dye penetrant examination). Although not
explicitly mentioned in Section I, the use of visual inspection is
certainly implied and is called out in B31.1 for application to the
boiler external piping. These examinations are often referred to
in the industry by the shorthand terms RT (radiographic test), UT
(ultrasonic test), MT (magnetic-particle test), PT (liquid-penetrant
test), and VT (visual examination).
Section I generally follows the Code practice of referring to
Section V, Nondestructive Examination, for the rules on how to
conduct the various examinations and also provides its own acceptance standards. For example, Table PW-11 calls for certain welds
to be examined by RT in accordance with PW-51 or UT in accordance with PW-52. These paragraphs in turn reference Section
V, Article 2 and Section V, Article IV, Mandatory Appendix VII
respectively but to the acceptance criteria contained within PW-51
and PW-52. Similarly, PG-25, Quality Factors for Steel Castings,
calls for MT or PT of all surfaces of castings in accordance with
Section V, but provides acceptance criteria within its own domain
(i.e., in paragraph PG-25).
Personnel performing and evaluating radiographic, ultrasonic,
and other nondestructive examinations are required to be qualified and certified as examiners in those disciplines, in accordance
with a written practice of their employer (see PW-50). This written practice must be based on a document called Recommended
Practice for Nondestructive Testing Personnel Qualification and
Certification, SNT-TC-1A, published by the American Society for
Nondestructive Testing. Note the use of the word testing, rather
than examination in this title, showing again that the industry tends
to use these terms interchangeably. SNT-TC-1A establishes three
categories of examiners, depending on experience and training,
designating them as Level I, II, or III, with Level III being the highest qualification. The lowest ranking examiner, Level I, is qualified
to perform NDE following written procedures developed by Level
II or Level III personnel. A Level I individual can also interpret and
accept the results of nondestructive examinations in accordance
with written criteria (except for RT and UT examinations). A Level
II individual has sufficient additional training and experience so
that under the direction of a Level III person, he or she can teach
others how to conduct, interpret, and accept the results of nondestructive examinations. A Level III examiner is the most qualified
and can develop and write procedures as well as establish a written practice for his or her employer. A Level III examiner can also
administer examinations to qualify Level I, II, and III examiners.
The American Society for Nondestructive Testing has another
document, entitled Standard for Qualification and Certification of
Nondestructive Testing Personnel, CP-189, which is an alternative
to SNT-TC-1a (remember, the latter is only a recommended practice). CP-189 requires Level III individuals to pass an examination
given by the ASNT and calls for the employer to give a further
examination, since the first examination may not assess the full
range of capability needed. In 1997 the Committee voted to allow
CP-189 to be used as an alternative to SNT-TC-1A, with the choice
left to the certificate holder. This alternative standard appeared in
the 1997 addenda to Section I.
PW-51 requires a complete set of radiographs for each job to
be retained and kept on file by the manufacturer for at least five
years. This requirement is based on the reasonable idea that the
radiographs might be of assistance in determining responsibility
(or lack of responsibility) for any defects, alleged or actual, subsequently discovered, or other problems that might occur in service.
Similarly, PW-52 requires a manufacturer who uses ultrasonic examination to retain a report of that examination for a minimum of
five years. Again, these records might prove useful should problems occur in service.
In 1990 the Committee added an explanation at the beginning
of paragraph PW-11 to guide users in resolving disagreements that
sometimes arise under the following circumstances. Section I normally exempts certain welds from radiography, such as circumferential welds in tubes complying with limits specified in PW-41.
Occasionally, a user will have these welds radiographed, revealing
imperfections that would have been cause for rejection if the welds
were ones for which Section I required radiography. The explanation added to PW-11 is intended to help resolve the dilemma posed
by such a situation, and illustrates Section I’s philosophy of accepting long satisfactory experience as a basis for code rules. Here is
that explanation: “Experience has demonstrated that welded butt
joints not requiring volumetric examination by these rules have
given safe and reliable service even if they contain imperfections
which may be disclosed upon further examination. Any examination and acceptance standards beyond the requirements of this
Section are beyond the scope of this Code and shall be a matter
of agreement between the Manufacturer and the User.” This guidance, while helpful, has unfortunately not sufficed to prevent disputes arising from the provisions of PW-11.
1.7.8
Hydrostatic Testing
The hydrostatic test is one of the last steps in the construction
of the boiler. Hydrostatic test requirements are given in PG-99 and
PW-54. These tests may be made either in the manufacturer’s shop
or in the field using water. Unlike Section VIII, Section I does not
permit the use of other fluids or pneumatic testing.
The hydrostatic test serves a number of purposes. Many members of the Code Committees believe that its major purpose is to
establish that the boiler (or pressure vessel) has been properly constructed and that it has a significant design margin, or safety margin, above and beyond its nominal maximum allowable working
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-29
pressure. (The hydrostatic test pressure is normally 1.5 times
MAWP.) In this sense, the hydrostatic test is seen to demonstrate
the validity of the design as a pressure container. Another important aspect of the hydrostatic test is that it serves as a leak test. Any
leaks revealed by the test must be repaired, and the boiler must be
retested (see PW-54).
The first edition of Section I in 1915 called for a hydrostatic test
at 1.5 times the Maximum Allowable Working Pressure, a basic
rule essentially unchanged to this day. We may surmise that the
choice of this pressure followed the practice of the time and was
seen to provide evidence that the boiler had been constructed with
a significant design margin. If a higher test pressure had been chosen, the stress in the components might have begun to approach
their yield strength, a situation to be avoided. To ensure that the
test was under control, a requirement that the test pressure not be
exceeded by more than 6% was also included.
Because of the increase in allowable stresses (see 1.7.2.4) there
was some concern that the hydrostatic test at 1.5 times the design
pressure could bring stresses during the test close to the yield
strength of the material. Consequently the Committee changed
PG-99 in the 1999 Addenda to limit the primary membrane stress
during a hydrostatic test of any kind of boiler to 90% of the yield
strength of the pressure parts. With the addition of the 90% yield
requirement, some questioned why the 6% control tolerance on
the 1.5 MAWP pressure was required so the 6% tolerance was removed in the 2004 Edition.
1.7.8.1 Prevention of Brittle Fracture. PG-99 requires the
hydrostatic test to be conducted using water “at no less than
ambient temperature, but in no case less than 70°F (20°C).” This
stipulation about the water temperature is intended to minimize
the possibility of catastrophic brittle fracture of heavy-walled pressure parts during the test. Brittle fracture is a type of behavior that
can occur when metal is under tensile stress when its temperature
is at or below its so-called nil-ductility transition temperature
(NDTT). Above this temperature, the metal behaves in a ductile
manner; below this temperature, its behavior is brittle. Contrasting
examples of these two types of behavior are the bending of a wire
hanger compared with the bending of a glass rod. The wire, which
is ductile, bends easily when its yield strength is exceeded and can
be restored to its original shape. The glass rod can carry a certain
amount of bending load, but then suddenly fractures in a brittle
manner when its yield strength is reached.
Any flaw, notch, or other discontinuity can raise stress at some
local area to the yield point. If the material is ductile, it can yield
locally with little harm done. If the material is below its NDTT, it
behaves in a brittle manner; when stress reaches the yield point, the
material may tear or form a crack, which can then grow suddenly
through the thickness, causing a catastrophic failure. The ability of
a material to resist tearing or cracking is a measure of its fracture
toughness.
Brittle fracture is generally not a concern for relatively thin
materials. The manufacturers of steels used in boilers have developed melting practices that usually result in nil-ductility transition
temperatures well below 70°F (20°C), ensuring adequate fracture
toughness during hydrostatic tests. The component of greatest
concern in a large utility boiler (so far as brittle fracture is concerned) is the drum, since it has very thick walls. (It happens that
thick vessels and headers are more susceptible to brittle fracture
than thinner components.) After a number of brittle failure accidents in the 1970s, the manufacturers of large boilers took steps to
lower the NDTT of heavy-walled parts such as drums (by slightly
modifying specifications for material ordered to achieve a finer
grained material with greater fracture toughness). Also, in some
instances the manufacturers of large boilers recommended to their
customers that any future hydrostatic tests of existing boilers be
conducted using warm or even hot water, to ensure ductile behavior at the time of the test. This became potentially hazardous for the
Authorized Inspector, and the Committee placed a 120°F (50°C)
limit on metal temperature during the hydrostatic test at the request
of the National Board. Also around this time, most boiler manufacturers switched from the use of SA-515 to SA-516 plate for
heavy-walled boiler drums, because the latter has greater fracture
toughness. Even so, heavy SA-516 plate is often examined metallurgically by boiler manufacturers to determine its NDTT, and if
that temperature is not well below 70°F (20°C), a hydrostatic test
using water warmer than 70°F (20°C) is recommended.
The concerns described above can be illustrated by considering
the design of a thick-walled drum for a large high-pressure boiler.
Such a drum would typically be made of SA-516 grade 70 plate.
The allowable stress used for designing the drum is about 18 ksi
(after an increase of 9% in 1999; see discussion in Design Stresses:
Past, Present, and Future in Section 1.7.2.4 and Test Pressure for
Drum-Type Boilers in Section 1.7.8.2). Accordingly, during the hydrostatic test, the actual average membrane stress in the drum wall
is approximately 1.5 times 18 ksi (124 MPa), or 27 ksi (186 MPa).
At first glance, this seems to be a reasonable margin below the
minimum cold yield strength of this material, which is about 38 ksi
(262 MPa). Unfortunately, this is not the case, because in a real
vessel there are always irregularities of various kinds present
that act as stress raisers. Examples include welds with undercuts,
grooves, or ridges. Ligaments between openings can also act as
stress raisers, as can changes in vessel geometry at transitions between materials of different thickness and at nozzle-to-shell junctions. These stress-raising irregularities, sometimes loosely called
notches, may cause a stress concentration of two or more. Thus in
a drum undergoing hydrostatic testing, it is very likely that local
surface stress at some of these notches may approach or exceed
the yield stress. At such a time, it is important that the boiler plate
material be warm enough for its behavior to be ductile so that local
yielding can occur without significant danger of initiating a brittle
failure. When the boiler is in normal service, it is, of course, at a
temperature that ensures ductile behavior. It is also at a pressure
much lower than that during the hydrostatic test, so that the stress
even at notches is likely to be well below the yield stress.
1.7.8.2 Test Pressure for Drum-Type Boilers. For most boilers, the hydrostatic test is conducted by slowly raising the pressure
to 1.5 times the MAWP. Close visual inspection is not required
during this stage, in the interest of safety of the Inspector. The
pressure is then reduced to the MAWP, and the boiler is carefully
examined for leaks or other signs of distress.
In 1999, after careful consideration, certain allowable design
stresses were increased below the creep range by changing in both
Sections VIII and I the design factor on tensile strength from about
4 to about 3.5. There had been some concern that to avoid yielding
in any of the pressure parts, this might require a reduction in the
hydrostatic test pressure. The Committee investigated the ramifications of what was really only a modest increase in some design
stresses and concluded that a reduction in hydrostatic test pressure
was unnecessary. However, the rules for hydrostatic tests in PG-99
were modified in the 1999 addenda to stipulate that “At no time
during the hydrostatic test shall any part of the boiler be subjected
to a general primary membrane stress greater than 90% of its yield
1-30 t Chapter 1
strength (0.2% offset) at test temperature.” The new words characterizing the limit as applicable to general primary membrane stress
were the first use of such terminology by Section I. They were chosen to make clear that the goal is to limit average membrane stress
through the wall of the components, and not the bending stress or
peak stress at the surface. A subsequent review of the materials
used in Section I construction showed that there is still a significant
margin between actual stresses during a hydrostatic test and yield
strength, as just noted in the discussion under Prevention of Brittle
Fracture.
Hydrostatic tests for Section VIII vessels can be conducted at a
much higher pressure than those for Section I boilers, because the
factor used to determine test pressure includes the ratio of the allowable stress at room temperature to the allowable stress at design
temperature. Because of this higher pressure, the Committee was
concerned about potential yielding during a hydrostatic test and
reduced the longstanding hydrostatic test pressure factor from 1.5
to 1.3 at about the same time as the new, somewhat higher stresses
were adopted in the 1999 addenda.
In addition to the 90% of yield strength limit for membrane
stress during a hydrostatic test introduced in the 1999 addenda,
historically PG-99.1 also required that the test pressure “be under
proper control at all times so that the required test pressure is never
exceeded by more than 6%.”
The rule that the test pressure must not be exceeded by more than
6%, that is, not more than (1.06)(1.50)(MAWP) = (1.59) (MAWP),
while arbitrary, is not unreasonable. As explained under the topic
Design Stresses: Past, Present, and Future in Section 1.7.2.4, one
of the criteria for setting allowable stress is two-thirds of the yield
strength of the material. Therefore, a hydrostatic test at 1.5 times
MAWP could theoretically utilize 100% of the yield strength of
those components with allowable stress that is based on the yield
strength at room temperature. There would then be little margin
for over-shooting the prescribed test pressure. However, this is not
the case for several reasons. First of all, for most Section I materials, the allowable stress at room temperature is actually based on
31.5 of the ultimate tensile strength, which is quite a bit lower than
two-thirds of the yield strength at that temperature. Moreover, the
yield strength (and ultimate tensile strength) of most materials as
received from the mill is somewhat stronger, often by 10% or more,
than the minimum called for by the material specification, although
no credit may be taken for this extra strength. Also, any components
intended for service at elevated temperature are designed using allowable stresses lower than those at room temperature (allowable
stress for many Section I materials is relatively constant from room
temperature to about 500°F (260°C) and then begins to fall off as the
temperature increases). Thus at test temperature, these components
have extra strength available to provide a margin against yielding.
During a typical hydrostatic test, a pump capable of providing a
large volume of water at relatively low pressure is used to fill the
boiler. Various vents are left open to permit all the air to escape,
and when the boiler is full of water, all valves are closed and a
different kind of pump is used, one that can achieve the high pressure required. Often the pump used for the hydrostatic test is a
piston-type pump that slowly builds pressure as any remaining air
pockets are filled with water. When the water-holding volume of
the boiler reaches the stage where it is essentially solid water, each
piston stroke raises the pressure substantially due to the essentially
incompressible nature of water. It thus may be difficult to achieve
the desired test pressure without overshooting the mark. Test personnel must be attentive at this time to avoid exceeding this test
pressure tolerance (established by the designer).
As might be expected, the maximum permitted hydrostatic test
pressure has occasionally been exceeded, and in a few cases, the
Authorized Inspector had refused to accept the boiler because PG99.1 states that the desired test pressure is never to be exceeded
by more than 6%. What to do? Inquiries came to the Committee,
where the sentiment was on the side of common sense, namely, that
if the manufacturer could demonstrate to the AI, by some means,
perhaps through calculations, that stresses during the test had not
exceeded the yield strength of the parts and that no damage had
been done to the boiler, the AI could accept the boiler. In 1981
Interpretation I-81-27, Maximum Hydrostatic Test Pressure, was
issued, as follows:
Question: Under what circumstances may the hydrostatic test
pressure stated in PG-99 be exceeded?
Reply: The test pressure may be exceeded when the manufacturer demonstrates to the satisfaction of the Authorized
Inspector that no component has been overstressed.
This Interpretation is also consistent with Section VIII’s design
philosophy, as expressed in UG-99, the counterpart to PG-99 in
Section I. Section VIII does not establish an upper limit for hydrostatic test pressure. Section VIII, UG-99(d) says that if the test
pressure exceeds the prescribed value, either intentionally or accidentally, to the degree that the vessel is subjected to visible permanent distortion, the Inspector shall reserve the right to reject the
vessel.
The Committee considered such an approach to be reasonable
and, at one point in the 1980s, actually voted to add a similar provision to Section I to settle future inquiries on this topic. However,
the Main Committee would not approve the change. Among the
objections offered was the assertion that it was too difficult for an
Inspector to see the slight deformation that would indicate yielding
had taken place. The fact that Section VIII had for years granted the
Inspector the discretion to make such a judgment was insufficient
to convince the negative voters, and the Committee abandoned the
effort. Interpretation I-81-27 cited above should serve to resolve
most problems about overshooting the prescribed hydrostatic test
pressure. Many felt that with the addition of the 90% yield criteria
in the 1999 Addenda that the 6% overpressure limit was no longer
needed so in the 2004 Edition, the 6% overpressure limit was removed from the Code. Section I now has only the requirement that,
at no time during the hydrostatic test, shall the primary membrane
stress exceed 90% of the yield strength at test temperature. This
would permit a reasonable degree of the test pressure exceeding
the 1.5 times the Maximum Allowable Working Pressure (MAWP)
without damage to the component. This is true with most materials
utilized in Section I construction but the Manufacturer is responsible to check to ensure that the selected hydrostatic test pressure
does not exceed the 90% yield criteria.
1.7.8.3 Forced-Flow Steam Generators with No Fixed Steam
and WaterLine. The usual hydrostatic testing procedure is
modified for forced-flow steam generators with no fixed steam
and water-line. These boilers are designed for different pressure
levels along the path of water-steam flow, with a significant difference between economizer inlet and superheater outlet. In one
such boiler, for example, those design pressures were 4350 psi
(29 MPa) and 3740 psi (25 MPa), respectively. The design pressure or MAWP at the superheater outlet is the design pressure
stamped on this type of boiler and is called the master stamping
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-31
pressure. In the first stage of the hydrostatic test, a pressure equal
to 1.5 times the master stamping pressure (but no less than 1.25
times the MAWP of any other part of the boiler proper) must be
applied. In the example given, the 1.5 factor controls, at 5610 psi
(37 MPa). For the second or close-examination stage, the pressure
may be reduced to the MAWP at the superheater outlet.
1.7.8.4 Welding After Hydrostatic Test. Formerly, the hydrostatic test completed the construction of the boiler, and no further
work (i.e. welding) was permitted as part of the ASME newconstruction process. However, around 1980, the Committee
added provisions to PW-54 permitting non-pressure parts to be
welded to the pressure parts after the hydrostatic test if certain
conditions are met. (Welding is limited to P-No. 1 materials;
attachment is done by stud welds or small fillet welds; 200°F
(95°C) preheat is applied when the thickness of the pressure part
exceeds ¾ in. (19 mm); and the completed weld is inspected by
the Authorized Inspector before he or she signs the Manufacturers’
Data Report Form for the completed boiler.) This change granted
relief from delays that arose when miscellaneous structural steel
parts to be welded to the pressure parts were not available, but the
pressure parts were ready for the hydrostatic test.
In 1999 Code Case permission was granted for the welding of
carbon steel attachments not classified as P-No. 1 material, but
having a maximum carbon content of 0.2%, to P-No. 1 pressure
parts after the hydrostatic test. Incorporation of the Code Case into
Section I was approved and it was published in the 2004 Addenda.
1.7.9
Third-Party Inspection
Third-party inspection refers to the system evolved by the
Code Committee to ensure that manufacturers or other Certificate
Holders will actually follow the Code rules. In the simplest situation, a boiler manufacturer and the boiler purchaser are the first
two parties, and an Authorized Inspector (AI) is the independent
third party. It is the function of the AI to ensure and verify that the
manufacturer complies with the Code.
Historically, an Authorized Inspector was defined by Section
I in PG-91 as an inspector employed by a state or municipality
of the United States, a Canadian province, or an insurance company authorized to write boiler and pressure vessel insurance.
The employer of an Authorized Inspector is called an Authorized
Inspection Agency (AIA). Thus an AIA can be either the inspection agency of an insurance company or of a jurisdiction that has
adopted and enforced at least one section of the code. In the United
States, the Authorized Inspection Agencies providing authorized
inspection for ASME Certificate Holders traditionally have been
private insurance companies such as the Hartford Steam Boiler
Inspection & Insurance Company, Factory Mutual Insurance Company, or One CIS Insurance Company among others. Starting with
the 2000 Addenda, PG-90.1 now refers to ASME QAI-1 [16] as
part of the definition of an AIA. This standard covers the qualification requirements for Authorized Inspection Agencies as well
as Authorized Inspectors and Authorized Inspector Supervisors.
For the Authorized Inspector, this standard then refers to National
Board document NB-263 which is RCI-1, Rules for Commissioned
Inspectors [17]. In Canada, until 1996, the provincial governments
had provided authorized inspection services through offices such
as the department of labor. However, in an effort to cut the cost
of government, two provinces (Alberta and Ontario) have privatized their authorized-inspection activities by spinning them off
into self-sustaining private companies. The new Alberta organization is called the Alberta Boilers Safety Association (ABSA), and
the new Ontario organization is called the Technical Standards
and Safety Authority (TSSA). The Canadian government passed
a bill allowing the delegation of authority over this public safety
program, formerly vested in the provincial governments, to notfor-profit nongovernment organizations. The new organizations
are Crown Corporations, the administrators of which are dual employees of the jurisdiction and the newly privatized corporations.
The National Board of Boiler and Pressure Vessel Inspectors has
accepted the new corporations as representing the jurisdiction.
The chief inspectors of the new corporations are National Board
members, as they were before the change. Other provinces may
follow the example set by Alberta and Ontario. As Code construction becomes increasingly an international activity, the National
Board may recognize and accept other foreign jurisdictions and
their inspection agencies, provided they meet certain criteria.
Through reference to QAI-1, the Authorized Inspector must be
qualified by written examination under the rules of the National
Board NB-263. When an Inspector is so qualified, he or she may
obtain a commission, or certificate of competency, from the jurisdiction where they are working. The National Board of Boiler
and Pressure Vessel Inspectors (the National Board) also grants
commissions to those who meet certain qualifications and pass a
National Board examination.
As a condition of obtaining from ASME a Certificate of Authorization to use the Certification Mark, each Section I manufacturer or assembler must have in force a contract with an
Authorized Inspection Agency spelling out the mutual responsibilities of the manufacturer or assembler and the Authorized
Inspector. The manufacturer or assembler is required to arrange
for the Authorized Inspector to perform the inspections called
for by Section I. Paraphrasing the words of A-300 (the Quality
Control System): the manufacturer shall provide the Authorized
Inspector access to all drawings, calculations, specifications, process sheets, repair procedures, records, test results, and any other
documents necessary for the Inspector to perform his or her duties in accordance with Section I. Section I lists many duties of
the Authorized Inspector, all of which are intended to ensure code
compliance. In 1997 the Committee approved the expansion of
PG-90 on Inspection and Tests to include a comprehensive list
of the AI’s duties and references to the paragraphs where those
duties are further described. The revised PG-90 appeared in the
1998 addenda. However, even when Section I does not specifically describe the duties of an AI with respect to some provision
of the code, it is understood that the AI has very broad latitude in
carrying out the mandate to verify compliance by the Certificate
Holders with all applicable Code rules.
During Committee deliberations, a number of members who
happen to be Authorized Inspectors have explained that once they
have established that a manufacturer is following its approved
quality control system, they merely spot-check the manufacturer’s
activities. As a practical matter, an AI cannot be expected to check
every detail of a manufacturer’s Code construction operation.
It may be recalled from the discussion of the preamble in Section
1.2 of this chapter that “the Code does not contain rules to cover all
details of design and construction” and that when complete details
are not given, the manufacturer must provide details of design and
construction as safe as those the Code does provide in its rules,
subject to the acceptance of the Authorized Inspector. An AI may
have sufficient experience to make a decision in such a situation,
in which case approval may be a simple matter. At other times,
because of new or unusual construction, the AI may seek guidance from a higher authority within his or her organization (many
1-32 t Chapter 1
Authorized Inspection Agencies maintain an engineering staff) or
via an inquiry to the Code Committee, to determine whether the
proposed construction is acceptable.
If a symbol stamp holder fails to comply with the Code, the AI
has several powerful remedies. The Authorized Inspector can require rework, additional NDE, or simply refuse to accept the boiler
(or other component). Without the AI’s signature on the Data Report Form, the boiler is not complete and cannot be sold or used
where the Code is enforced. For repeated violations, the AI might
also recommend that the contract for Authorized Inspection not be
renewed. Finally, if the violations were flagrant, the matter could
be brought to the attention of the Committee on Boiler and Pressure Vessel Conformity Assessment. The Committee would then
conduct a hearing that could lead to the revocation of the offender’s
Certificate of Authorization to use the Certification Mark. The loss
of the Certificate of Authorization could impact their business so
third-party inspection provides a very effective means of assuring
Code compliance.
1.7.10
Certification by Stamping and Data Reports
1.7.10.1 Certification and Its Significance. For the Code to
be effective, there must be some means of ensuring that it has
been followed. Each phase of the work of designing, manufacturing, and assembling the boiler must be done in accordance with
the Code. Assurance that a boiler is constructed to the Code is
provided in part by a process called Code certification, described
in PG-104. In the simplest case of a complete boiler unit made by
a single manufacturer, the manufacturer must certify on a form
called a Manufacturers’ Data Report Form (see below) that all
work done by the manufacturer or others responsible to the manufacturer complies with all requirements of the Code. When some
portion is performed by others not responsible to the manufacturer,
the manufacturer must obtain the other organization’s Code certification that its work complied with the Code. In addition, the
manufacturer must stamp the boiler with the Certification Mark,
which signifies that it has been constructed in accordance with the
Code. Certification thus is an integral part of a quality assurance
program, which establishes that
(1) the organization that did the work held an appropriate ASME
Certificate of Authorization to use the Certification Mark;
(2) the organization has certified compliance with the Code
rules by signing and furnishing the appropriate Manufacturers’ Data Report Form;
(3) the organization has applied the Certification Mark to identify the work covered by its Data Report Form; and
(4) a qualified Inspector has confirmed by his or her signature
on the Data Report Form that the work complied with the
applicable Code rules.
In the case of a complete boiler unit that is not manufactured
and assembled by a single manufacturer, the same principles are
followed. There is always one manufacturer who must take the
overall responsibility for ensuring through proper Code certification that all the work complies with the requirements of the Code.
If, for example, the manufacturer of a boiler buys the drum (or
any other part) of the boiler from another manufacturer, that other
manufacturer must follow similar certification and stamping procedures. The part manufacturer must have a Certificate of Authorization to use the Certification Mark, certify compliance with all
the Code rules on a Manufacturers’ Data Report Form, and stamp
or otherwise identify the part; in addition, an Authorized Inspector
must sign the form as confirmation that the work complied with
the applicable Code rules. That form becomes part of the complete
documentation assembled by the manufacturer of record. In general, the manufacturer of record has the duty of obtaining from all
organizations which have done any Code work on the boiler their
proper Code certification for that work.
The same approach is used to certify that portion of the work
called field assembly for those boilers that are too large to be completely assembled in the shop. The Manufacturers’ Data Report
Form typically has a certification box for use by the assembler of
a boiler.
1.7.10.2 Manufacturers’ Data Report Forms and Their
Distribution. Section I has 13 different Manufacturers’ Data
Report Forms (MDRFs) that have evolved over the years to cover
various types of boilers and related components. These forms
serve several purposes, one of which is to provide a documented
summary of certain important information about the boiler: its
manufacturer, purchaser, location, and identification numbers.
Most forms also provide a concise summary of the construction
details used: a list of the various components (drum, heads, headers, tubes, nozzles, and openings), their material, size, thickness,
type, etc., and other information such as the design and hydrostatic
test pressures and maximum designed steaming capacity.
The forms and their use are described in PG-112, in PG-113,
and in Appendix A-350, which contains examples of all the forms
and a guide for completing each one. Also in the Appendix (page
A-357) is a so-called Guide to Data Report Forms Distribution.
This guide explains which forms should be used in ten different circumstances involving several types of boilers that may be
designed, manufactured, and assembled by different Certificate
Holders. There are so many forms and combinations of forms that
can be used that the subject can often be quite confusing. What is
important to remember is the purpose of the forms: to provide a
summary of essential information about the parts composing the
boiler and to provide for certification, as appropriate, by all those
involved (the various manufacturers and inspectors) that all components of the boiler were constructed to the rules of Section I. At
the same time, it is also important to understand that the MDRFs
were never intended to be all-inclusive catalogs or parts lists for
the boiler or substitutes for the manufacturers’ drawings. If more
information is needed than is found on the forms, it can be found
on those drawings.
Certain of the forms are sometimes called Master Data Report
Forms. A Master Data Report Form, as the name implies, is the
lead document when several different forms are used in combination to document the boiler. The P-2, P-2A, P-2B, P-3, P-3A, and
PL-1 forms can be used as Master Data Report Forms. The other
forms (the P-4, P-4A, P-4B, and P-6) usually supplement the information on the Master Data Report Forms and are attached to them.
Manufacturers Data Report Forms P-7 and P-8 cover the manufacturer and assembly of Safety and Pressure Relief Valves.
PG-112.3 requires copies of the Manufacturers’ Data Report
Forms to be furnished to the purchaser, the inspection agency, and
the municipal, state, or provincial authority at the place of installation. In addition, many jurisdictions require registration of the
boiler with the National Board, which would then be sent copies
of the Manufacturers’ Data Report Forms. Many boiler manufacturers routinely register all their boilers with the National Board.
Thus the concerned organizations have available a valuable summary of the design data and the technical details of the boiler. This
can be very helpful many years later for investigations, repairs, or
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-33
alterations when original plans may have disappeared or are not
readily available. Surprisingly, this is often the case. Having such
information as the applicable Code edition and the details of original components can facilitate any subsequent work on the boiler.
The designer then knows the design pressure, the size, thickness,
material, allowable stress, and design formulas originally used and
can make appropriate choices for repair, replacement, or alteration. Copies of Data Report Forms on file with the National Board
can be readily obtained from that organization, and this is a major
benefit of National Board registration (a service available for both
boilers and pressure vessels).
1.7.10.3 Certification Marks and How They are Obtained.
The ASME committee that formulated the first edition of the Code
in 1915 recognized a need to identify in a unique way any boiler
constructed to meet the Code. They decided to do this by having
the manufacturer stamp the boiler with a Code symbol. Paragraph
332 of that original edition stipulates, in part, “Each boiler shall
conform in every detail to these Rules, and shall be distinctly
stamped with the symbol shown in Fig. 19, denoting that the boiler
was constructed in accordance therewith. Each boiler shall also be
stamped by the builder with a serial number and with the builder’s
name either in full or abbreviated. . . .” The official symbol for
such a boiler was then, an S enclosed in a cloverleaf. That symbol
is evidence that the boiler complies with the Code and represents
an assurance of safe design and construction. A great many provisions of Section I are directed to making sure that this will be so.
Over the years, Section I has added other symbol stamps, and
there are now a total of six covering different aspects of boiler construction. Until the late 1970s, there was also an L stamp, used for
locomotive boilers, but by that time there were only two manufacturers who were still authorized to use the L stamp. The Committee
decided to abolish what had become an obsolete stamp, and those
last two manufacturers were given S stamps instead.
In 2011 ASME changed the code symbol stamp to a Certification Mark (see Figure PG-105.1—included here for reference) to be
used with a Designator. The Designator will be located immediately
below the Certification Mark in the 6 o’clock position. The Designators applicable to Section I construction (from the 2015 Edition)
are listed below:
(a)
(b)
(c)
(d)
(e)
(f)
(g)
S—power boiler Designator
M—miniature boiler Designator
E—electric boiler Designator
A—boiler assembly Designator
PP—pressure piping Designator
V—boiler pressure relief valve Designator
PRT—fabricated parts Designator
Except under certain carefully controlled circumstances, no
organization may do Code work (e.g., fabricate or assemble any
Section I boiler components) without having first received from
the ASME a Certificate of Authorization to use the Certification
Mark with one of the Designators. Before an organization can obtain such a certificate, it must meet certain qualifications, among
which are the following.
1.
The
organization
(manufacturer,
assembler,
or
engineering-contractor) must have in force at all times
an agreement with an inspection agency (the Authorized
Inspection Agency, or AIA), usually an insurance company
authorized to write boiler and pressure vessel insurance,
or with a government agency or government authorized
agency (see Section 1.7.9, Third-Party Inspection) that
administers a boiler law in that jurisdiction. This agreement
covers the terms and conditions of the authorized Code inspection to be provided and stipulates the mutual responsibilities of the manufacturer or assembler and an inspector
provided by the inspection agency. These inspectors, called
Authorized Inspectors, must be qualified by written examination under the rules of any state of the United States
or province of Canada whose boiler laws have adopted
Section I. Authorized Inspectors provide the inspection
required by Section I during construction or assembly and,
after completion, of any Section I component.
(Source: ASME SECTION I)
1-34 t Chapter 1
2.
3.
A further requirement for obtaining a Certificate of
Authorization to use the Certification Mark is that the
manufacturer or assembler must have, and demonstrate,
a quality control system to establish that all Code requirements will be met. These pertain to material, design
(except for the PRT designator as noted below), fabrication, examination by the manufacturer or assembler, and
inspection by the Authorized Inspector. An outline of the
features required in the quality control system is provided in paragraph A-300 of the Appendix and is discussed
in Section 1.7.11 below.
Finally, before the ASME issues (or renews) a Certificate of
Authorization, the manufacturer’s or assembler’s facilities
and organization are reviewed by a team consisting of a representative of the inspection agency (AIA) and an individual certified as an ASME Designee, who is selected by the
legal jurisdiction involved. The manufacturer or assembler
must make available to the review team a written description of the quality control system that explains what documents and procedures will be used to produce or assemble
a Code item. On recommendation of the review team, the
ASME issues (or renews) a Certificate of Authorization to
use the Cerification Mark, normally for a period of three
years.
The “PRT” designator was added in the 2015 Edition and has
one important distinction when compared to the other designators.
This designator is for fabrication of parts only and does not include
design responsibility. Many organizations build to print and note in
the Remarks section of Form P-4 that the design was performed by
others. The issue for these Manufacturers is that even though they
never perform design, they still had to demonstrate design ability
as part of the process of obtaining a Certificate of Authorization to
use the Certification Mark (see the next paragraph). With the addition of the “PRT” designator, an organization that does not perform
design can now obtain a Certificate of Authorization without having to demonstrate design ability.
1.7.11
Quality Control System
In 1973, the ASME Boiler and Pressure Vessel Committee
adopted comprehensive and detailed rules for what is called a
quality control (QC) system in Sections I, IV, and VIII, the boiler
and pressure vessel sections of the Code. In Section I, these rules
are found in PG-105.4 and Appendix A-300, both entitled Quality Control System. Each manufacturer (or other certificate holder,
such as an assembler) is required to have a documented quality
control system that is fully implemented into its manufacturing
operations. See Appendix J of B31.1 Power Piping Code Quality
Control Requirements for Boiler External Piping (BEP).
The QC system is intended to control the entire manufacturing
process from design to final testing and certification. The scope
of such systems may vary significantly among manufacturers,
since the complexity of the work determines the program required;
however, the essential features of a QC system are the same for
everyone. Each manufacturer is free to determine the length and
complexity of its Quality Control Manual, making it as general or
detailed as desired. It is not advisable to include detailed practices
in the manual that are not actually followed in the shop. Also, when
shop practices are revised, the manual must be updated to reflect
the revisions. Otherwise the Authorized Inspector is likely to find
nonconformities, which will cause considerable extra work before
full compliance with the code can be demonstrated. Implicit in the
code QC requirements is recognition that each manufacturer has its
own established practices and that these are acceptable if a documented system can be developed showing control of the operation
in conformance with Code requirements. It is also recognized that
some of the information included in a written description of a quality control system is proprietary, and no distribution is required
other than to the Authorized Inspector.
An outline of features to be incorporated into a Section I quality
control system is found in the A-302 paragraphs. These paragraphs
are a list of requirements that have proven to be relatively easy to
understand and have worked well. To begin, the authority and responsibility of those performing quality control functions must be
established. That is, the manufacturer must assign an individual with
the authority and organizational freedom to identify quality problems
and to recommend and implement corrective actions should they be
needed. In addition, the written system must include the following:
t The manufacturer’s organization chart, showing the relationship between management, engineering, and all other groups
involved in the production of Code components and what the
primary responsibility of each group is. The Code does not
specify how to set up the organization, nor does it prevent the
manufacturer from making changes, so long as the resultant
organization is appropriate for doing Code work.
t Procedures to control drawings, calculations, and specifications. That is, the manufacturer must have a system to ensure
that current drawings, design calculations, specifications, and
instructions are used for the manufacture of Code components.
t A system for controlling material used in Code fabrication to
ensure that only properly identified and documented material
is used.
t An examination and inspection program that provides references to Nondestructive Examination Procedures and to
personnel qualifications and records needed to comply with
the Code. Also required is a system agreed upon with the
Authorized Inspector for correcting nonconformities. A nonconformity is any condition that does not comply with the
rules of the Code, whether in material, manufacture, or the
provision of all required appurtenances and arrangements.
Nonconformities must be corrected before the component can
be considered to comply with the Code.
t A program to ensure that only weld procedures, welding
operators, and welders that meet Code requirements are used
to produce Code components. This is normally one of the
most detailed and important sections of the QC Manual, and
it describes how qualified weld procedures are maintained
and used and who within the organization is responsible for
them. It also includes details on how welder qualifications are
established and maintained.
t A system to control postweld heat treatment of welded parts
and any other heat treatment, such as might be required following tube bending or swaging. This system must also provide means by which the Authorized Inspector can verify that
the heat treatment was applied.
t A system for calibration of examination, measurement,
and test equipment used in Code construction to ensure its
accuracy. The Code does not require such calibrations to be
traceable to a national standard such as those maintained at
the National Institute of Science and Technology (NIST). It
merely states that the equipment must be calibrated.
t A system of record retention for such items as radiographs
and Manufacturers’ Data Reports.
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-35
t Procedures covering certain other activities of the manufacturer, such as hydrostatic testing.
t Procedures and controls for any intended subcontracting of
any aspect of Code construction, such as design, radiography,
or heat treatment.
Appendix A-300 concludes with the admonition that the quality
control system shall provide for the Authorized Inspector to have
access to all drawings, calculations, records, procedures, test results, and any other documents necessary for him or her to perform
the inspections mandated by Section I. The objective is to ensure
the quality of the construction and compliance with the Code. Note
also that the quality control system may not be changed without
obtaining the concurrence of the Authorized Inspector.
As explained in Section 1.7.10.3, Certification Marks and How
They are Obtained, one of the conditions for the issuance or renewal of a Certificate of Authorization to use one of the ASME
Certification Mark with the appropriate Designator is that the manufacturer or assembler must have a quality control system that is
intended to ensure all Code requirements will be met. Furthermore,
the QC system must be demonstrated to a review team.
The issuance by the ASME of a new Certificate of Authorization or the required triennial renewal of an existing Certificate of
Authorization is based on a favorable recommendation after a joint
review of the written quality control system by a representative of
the manufacturer’s Authorized Inspection Agency and a representative of the legal jurisdiction involved. In those areas where there
are no jurisdictional authorities or when the jurisdiction declines
to participate, the second member of the review team is a qualified
ASME review team leader.
1.8
FUTURE CHANGES
As mentioned at the end of the Introduction in section 1.1,
Section I is a living document and is continually updated. At the
time of updating this book (2016), the Committee is working towards publication of the 2017 Edition and is also working on items
for the 2019 Edition. This section highlights some of the items being worked on which may be included in a future publication of
Section I.
1.8.1
Replacement Parts
Pressure testing of replacement parts has long been a grey area
between Section I, the NBIC, and the jurisdictions. Section I has
requirements for pressure testing a completed boiler in PG-99
and pressure testing of parts in PW-54. Under PW-54, it indicated
that the testing of the part may be made in the shop or in the field.
Some questioned whether it was acceptable to stamp a part and
ship to the field for a field assembled boiler without performing a
hydrostatic test of the part before applying the stamp to the part.
This was addressed with a change to PG-106.8 in the 1996 Addenda to clarify that parts could be stamped without being pressure tested prior to shipment, as they would receive a pressure
test with the completed boiler. This has caused confusion with
some users and Jurisdictions when installing replacement parts in
existing units. The NBIC has alternates to full hydrostatic pressure tests for repairs and alterations (including installing parts as
part of those repairs and alterations). This means that the welds
made in the fabrication of the parts themselves may never receive
a full hydrostatic pressure test. Some felt that this was then a
violation of PW-54 which states that “…drums and other welded
pressure parts shall be subjected to a hydrostatic test…” The
Committee has passed an intent interpretation together with a revision to PW-54 for publication in a future edition (intended to
publish in the 2017 Edition) that will clarify that the hydrostatic
test referenced in PW-54 is the hydrostatic test of the completed
boiler in PG-99.
1.8.2
Digital Radiography
As mentioned in 1.7.7, Nondestructive Examination, Section I
requires the Manufacturer to keep a complete set of radiographs for
a period of 5 years. With the development of digital radiography
and the technology to convert radiographic film to digital images,
some users have questioned whether storing digital images satisfies Section I requirements. This was addressed by the Committee
in two interpretations issued in 2015.
Question: Does the phrase “A complete set of radiographs”
in PW-51.4 cover the Digital Radiographs taken using DR/
CR (Digital Radiography/Computed Radiography) Industrial
Radiography Systems?
Reply: Yes.
Question: Radiographic film is often converted to digital images to ease storage, reproduction, and distribution of the
images. Is it acceptable per the requirements of PW-51.4 to
retain the converted digital images in-lieu of retaining the radiograph film?
Reply: No.
For the interpretation regarding converting film to digital images, many on the Committee felt that it would be acceptable but
had to answer “No” as there were no words in the Code to support
a “Yes” reply. To address that, the Committee has passed a revision
to PW-54.1 which when published in a future edition (intended
to publish in the 2017 Edition) will clarify that radiographs may
be stored as film or digital images and that if film is digitized, the
digitization shall be in accordance with Section V, Article 2, Mandatory Appendix III.
1.8.3
Advanced NDE
In the 2015 Edition of Section V, a new Mandatory Appendix II
was added to Article 1. This mandatory appendix provides guidance for employers in developing their written practice for qualifying personnel on some of the more advanced NDE techniques
(computed radiography, digital radiography, phased array UT, and
time of flight diffraction UT). The Committee has approved a revision for publication in a future edition (intended to publish in the
2017 Edition) which references Section V, Article 1, Mandatory
Appendix II.
1.8.4
Corrosion
As indicated in 1.7.2.9 Corrosion/Erosion Allowance, the
designer has the responsibility to determine whether a corrosion
allowance is needed and, if so, the amount and location. There
have been multiple inquiries over the years regarding the need for
a corrosion allowance and how to apply it so the Committee has
approved revisions for publication in a future edition (intended to
publish in the 2017 Edition) which provide guidance on how to
apply corrosion allowance (when specified) in design equations.
These changes are somewhat consistent with UG-16(e) of Section
VIII Division 1.
1-36 t Chapter 1
In a related action, the Committee has approved the addition of
a new nonmandatory appendix for publication in a future edition
(intended to publish in the 2017 Edition) that will provide guidance
for manufacturers in regards to minimizing the effects of fireside
corrosion, erosion, and steam side oxidation for high temperature
components in coal fired boilers.
1.8.5
PWHT of P-No. 1 Group 1
As mentioned in 1.7.4.10, Postweld Heat Treatment, the table of
exemptions for P-No. 1 materials has been simplified to provide
exemptions for welds up to 1½ in. (38 mm) regardless of type of
weld. The Committee has approved another change for to Table
PW-39-1 for publication in a future edition (intended to publish in
the 2017 Edition) that extends the exemption for P-No. 1 Group 1
materials by removing the 1½ in. (38 mm) upper limit. The existing limitations will now only apply to P-No. 1 Groups 2 and 3.
1.8.6
Local PWHT of Creep Strength Enhanced
Ferritic Steels
The class of materials known as creep strength enhanced steels,
particularly the P-No. 15E materials, are not only dependent on
chemistry to achieve the desired properties but also on the thermal processing history of the materials. A big part of that history
is PWHT and industry studies and experience have demonstrated
that local PWHT must be tightly controlled to be effective. To address this, a new nonmandatory appendix has been approved by the
Committee for publication in a future edition (intended to publish
in the 2017 Edition) that provides recommendations for the set-up
and application of local PWHT to P-No. 15E materials using electric resistance heating elements.
1.8.7
Material Traceability
PG-77 provides requirements for marking of plate material used
for shells, furnace sheets, and heads and requires that the markings
be visible when the boiler is completed. The requirements are unique
in that they only apply to plate materials. There are no corresponding
requirements for other material product forms other than the requirement in A-302.4 that the manufacturer have a material control system
that ensures that only the intended material is used in Code construction. There is no other information on what should be included in that
material control system. A user requested clarification of the applicability of the PG-77 requirements to other product forms so the Committee has approved a revision to PG-77 for publication in a future
edition (intended to publish in the 2017 Edition). Unlike the requirements for plate, this will not specifically require that the markings
on other product forms be visible in the completed boiler but instead
will require that the identification of material be maintained until the
data report for the item containing the material is complete. As an
example, if the material is a pipe used in construction of a header and
the header is documented on a Form P-4 Manufacturer’s Partial Data
report, the identification must be maintained until that data report is
completed; any markings on the pipe are not required to be visible in
the completed boiler. The revised paragraph will provide guidance
on some of the acceptable ways for maintaining identification (color
coding, abbreviated marking, written record, etc.). It should be noted
that the identification only has to be to the material type (such as
grade 22, grade 91, etc.), not to the MTR for the material.
1.8.8
Modernization of Section I
As pressure, temperature, and cycling requirements continue
to increase, some feel that Section I needs to be “modernized” to
address these advancing conditions. To address this, the Committee formed a task group to review Section I, other sections of the
Boiler and Pressure Vessel Code, and other international standards
to identify areas that need to be addressed. Items being considered
are how to perform fatigue assessments, restrictions on certain geometries for cycling service, allowing design by analysis in place
of or to compliment the use of design by rule, tighter controls on
welding and heat treatment, advanced NDE or more stringent acceptance criteria, etc.
1.8.9
Solar
As noted in 1.4.3, Fired versus Unfired Boilers, the Committee
formed a new committee to address solar power. This committee is
working on requirements for molten salt solar receivers for publish
in a future edition and maybe an early implementation Code Case.
1.8.10
Liquid Phase Thermal Fluid Heaters
Some jurisdictions require that liquid phase thermal fluid heaters be constructed and stamped in accordance with Section I. The
only place in Section I that currently addresses these devices is in
PG-2.4 which states that they may be constructed and stamped in
accordance with Section I provided all applicable requirements are
met. There is no guidance on which requirements are applicable
(or which may not be). The Committee received a request from a
Manufacturer to revise Section I to clarify which requirements are
applicable. The task group assigned is working on developing a
new Part for these devices.
1.8.11
Cold Forming of Carbon
and Carbon-Molybdenum Steels
In the late 1960’s and early 1970’s, cold bends in some boiler
circuits made from carbon steel and carbon-molybdenum steel
were prone to premature and catastrophic failure in the extrados
of the cold bends. Each US boiler manufacturer developed preventative actions that alleviated failures but these actions have not
been incorporated into the rules of Section I. Many current manufacturers are not aware of these failures, or more importantly the
preventative actions, so the Committee is considering adding cold
forming rules for carbon and carbon moly steels.
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Section I of the ASME Boiler and Pressure Vessel Code. NewYork :
ASME Press, 1998.
3. MacKay, John R and Pillow, James T. Power Boilers: A Guide to
Section I of the ASME Boiler and Pressure Vessel Code, Second
Edition. New York : ASME Press, 2011.
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American Society of Mechanical Engineers.
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COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-37
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14. ASME Code for Pressure Piping B31, Process Piping - B31.3. s.l. :
American Society of Mechanical Engineers.
15. SYNOPSIS of Boiler and Pressure Vessel Laws, Rules, and
Regulations. Louisville, KY: Uniform Boiler and Pressure Vessel
Laws Society, 2000.
16. Qualifications for Authorized Inspection. ASME QAI-1.
17. Rules for Commisioned Inspectors. s.l. : The National Board of Boiler
and Pressure Vessel Inspectors. NB-263, RCI-1.
18. Welded and Seamless Wrought Steel Pipe. s.l. : The American Society
of Mechanical Engineers. ASME B36.10M-2015.
19. Valves—Flanged, Threaded, and Welding End. s.l. : The American
Society of Mechanical Engineers. ASME B16.34-2013.
1.10
DESIGN EXERCISES
1.10.1 Design Exercise No. 1, Design of a Header
This first problem illustrates the use of Section I’s method of
design-by-rule, using the rules of paragraph PG-27 to design a
header. The reader is advised to review PG-27 before attempting
to solve the problem or looking at the solution. When reviewing
PG-27, note that slightly different formulas are used for designing
pipe and tubes.
It has been decided to make a certain cylindrical superheater
header from pipe, using 10 in. nominal pipe size (NPS) of appropriate wall thickness for a maximum allowable working pressure
of 1020 psi. Applying Section I formula PG-27.2.2 with a 10.75 in.
outside diameter and an allowable stress of 10,800 psi (at an 800°F
design temperature) for SA-106 Grade B pipe material, determine
the minimum wall thickness required. Then select the lightest pipe
adequate for this design pressure, from a table showing standard
pipe sizes and wall thicknesses varying according to schedule
number. Assume the constant C (for threading and structural stability) in formula PG 27.2.2 is zero, and determine the temperature coefficient y from the table in PG-27.4.6. Assume also that
no corrosion allowance is needed, that the hydrostatic head, which
normally must be included in the design pressure when designing pipe, is negligible in this case, and that there are no openings
or connections that would require compensation or ligament efficiency calculations. For ready reference, a table of pipe sizes from
ASME B36.10M-2015 has been included at the end of this chapter.
1.10.1.1 Solution to Design Exercise No. 1: The minimum
required thickness of the header may be calculated from the formula shown in PG-27.2.2. as follows:
t=
PD
+C
2SE + 2 yP
where:
D = outside diameter of cylinder = 10.75 in.
C = minimum allowance for threading and structural stability
(see PG-27.4.3) = 0
E = efficiency (see PG-27.4.1) = 1.0
P = maximum allowable working pressure = 1020 psi
S = maximum allowable stress value at design temperature =
10,800 psi
y = temperature coefficient (see PG-27.4.6) = 0.4
We can then find from that formula that the minimum thickness
required is 0.49 in., as follows:
t=
(1020)(10.75)
= 0.49 in.
2(10800) + 2(0.4)(1020)
We now go to a standard table of pipe sizes and thickness that is
derived from ASME B36.10, Welded and Seamless Wrought Steel
Pipe [18]. Note that for any diameter, the wall thickness varies in
accordance with the so-called schedule number of the pipe. The
table shows that schedule 60 NPS 10 appears to have just about the
wall thickness we need: 0.50 in. However, this is not the case because the thickness listed in the table is nominal and is subject to an
undertolerance, as explained in PG-27.4.7. This 12.5% undertolerance on thickness is given in ASME Specification SA-530 covering general requirements for carbon and alloy steel pipe. It is also
found in the individual pipe specifications listed in PG-9, for example, in paragraph 19.3 of the SA-106 pipe specification. Accordingly, we must go to the next commonly available wall thickness
among the specifications approved by the ASME. The table shows
that 0.562 in wall thickness pipe is available and this would satisfy
our needs (0.562 × 0.875 = 0.491 in). The schedule sizes listed in
B36.10M are often more readily available than the intermediate
thickness listed so a user may decide to select schedule 80, with a
nominal wall thickness of 0.594 in. Even with an undertolerance of
12.5%, the minimum thickness at any point in this pipe would be
0.875 * 0.594 in. = 0.52 in., which satisfies our required minimum
of 0.49 in. Our final choice would therefore be an NPS 10 schedule
80 SA-106 Grade B pipe of whatever length is required.
1.10.1.2 Alternate Solution to Design Exercise No. 1: PG-27.1
permits the use of the equation given in A-317 of Appendix A in
lieu of the equation provided in PG-27 for the calculation of cylindrical components under internal pressure.
Using the same parameters as used in Design Exercise No.1,
calculate the required header thickness using the equations in Appendix A-317. The minimum required thickness of the header may
be calculated from the formula shown in A-317.2.1, as follows:
æ Pöù
é
ç- ÷
D ê1 - eè SE ø ú
ê
ú
û +C + f
t= ë
2
where:
D = outside diameter of cylinder = 10.75 in.
C = minimum allowance for threading and structural stability
(see A-317.3, Note 3) = 0
E = efficiency (see A-317.3, Note 1) = 1.0
e = the base of natural logarithms
1-38 t Chapter 1
P = maximum allowable working pressure = 1020 psi
S = maximum allowable stress value at design temperature =
10,800 psi
E = efficiency (see A-317.3, Note 1)
f = thickness factor for expanded tube ends (see A-317.3, Note 4)
æ
1020 ö ù
é
ç÷
10.75 ê1 - eè (10800)(1) ø ú
ê
ú
ë
û + 0 + 0 = 0.48 in.
t=
2
1.10.2
Design Exercise No. 2, Design of a Head
Design Exercise No. 1 consisted of the design of a cylindrical
header, which turned out to be an NPS 10 schedule 80 SA-106
Grade B pipe (with a 10.75 in. OD and a nominal wall thickness of
0.594 in.). In this exercise, various heads for that header will be designed starting with a so-called dished head and using the rules of
paragraph PG-29.1. (Dished heads are usually standard catalog items
furnished as standard pressure parts under the rules of para-graph PG11). Again the reader is advised to review PG-29 before proceeding.
(A) For the same maximum allowable working pressure of 1020 psi
and design temperature of 800°F, determine the required thickness of
a blank, unstayed dished head with a 10 in. radius L on the concave
side of the head. Assume the head is made of SA-516 Grade 70 material. The maximum allowable working stress, S, from Section II, Part
D, is determined to be 12,000 psi. Verify this value if you have available a copy of Section II, Part D. Notice that the allowable stress for
this material is higher than that of the pipe material.
(B) PG-29.7 provides a rule for the design of a semiellipsoidalshaped head. What minimum thickness would be needed if this
type of head were used?
(C) PG-29.11 provides the rules for designing a full
hemispherical-shaped head. What minimum thickness would be
required if this type of head were used?
1.10.2.1 Solution to Design Exercise No. 2(A): The minimum
required thickness of the head is calculated using the formula in
PG-29.1 as follows:
t = 5PL /4.8Sw
where:
L = radius to which the head is dished, measured on the concave side of the head = 10 in.
P = maximum allowable working pressure (hydrostatic head
loading need not be included)—1020 psi
S = maximum allowable working stress, using values given in
Section II, Part D, Subpart 1, Table 1A = 12,000 psi
t = minimum thickness of head
w = weld joint strength reduction factor per PG-26 = 1
t=
5(1020)(10)
= 0.89
(4.8)(12000)(1)
1.10.2.2 Solution to Design Exercise No. 2(B):
t = 0.49 in.
The explanation is that PG-29.7 says that a semiellipsoidal head
shall be at least as thick as the required thickness of a seamless
shell of the same diameter. Thus, the answer derived in Design
Exercise No. 1 applies.
1.10.2.3 Solution to Design Exercise No. 2(C): The thickness
of a full hemispherical shaped head is calculated in accordance
with the formula in PG-29.11 as follows:
t=
PL
2Sw - 0.2P
where:
L = radius to which the head was formed, measured on the concave side of the head = 10.75/2-0.594 = 4.781 in.
P = maximum allowable working pressure = 1020 psi
S = maximum allowable working stress, using values given in
Section II, Part D, Subpart 1, Table 1A = 12,000 psi
t = minimum thickness of head
w = weld joint strength reduction factor per PG-26 = 1
t=
(1020)(4.781)
= 0.21 in.
2(12000)(1) - 0.2(1020)
Note that L is the inside radius of the head. In this case, it was
chosen to match the nominal inside radius of the piece of pipe used
for the header in Design Exercise No. 1.
From the results of these three head-thickness calculations, it is
clear that the hemispherical head is the most efficient shape, requiring a thickness only a fraction of that required for a dished or
an ellipsoidal head, and only about half that of the header to which
it is attached. This is because a hemispherical head carries pressure loads predominantly by developing membrane stresses, while
the ellipsoidal and especially the dished heads develop significant
bending stresses in addition to the membrane stresses.
Note also that paragraph PG-16.3 establishes the minimum
thickness of boiler plate under pressure as 1/4 in. (6 mm) in most
cases.
1.10.3
Design Exercise No. 3, Choice of Feedwater
Stop Valve
From the provisions of PG-42, it is seen that most boiler valves
are furnished in compliance with the ASME product standard for
valves, ASME B16.34, Valves—Flanged, Threaded, and Welding
End [19]. This standard provides a series of tables for various material groups, giving pressure-temperature ratings according to what
are called pressure classes. The classes typically vary from the 150
class (the weakest) to the 4500 class. For each class, the allowable
pressure is tabulated as a function of temperature. The allowable
pressure at any temperature is the pressure rating of the valve at
that temperature. Temperatures range from the lowest zone, –20°F
to 100°F, to 850°F and higher, depending on the material group.
The allowable pressure for the valve falls with increasing temperature, since it is based on the allowable stress for the material.
The designer of a valve for Section I service must select a valve
whose pressure rating at design temperature is adequate for the
Maximum Allowable Working Pressure (MAWP) of the boiler.
However, feedwater and blowoff piping and valves are designed
for a pressure higher than the MAWP of the boiler, because they
are in a more severe type of service called shock service. Design
rules for feedwater piping are found in paragraph 122 of B31.1,
Power Piping. The shock service somewhat complicates the choice
of the valve; to clarify the choice, Subcommittee I issued Interpretation I-83-91. The following example illustrates the choice of a
feedwater stop valve following the procedure outlined in the fourth
reply of that interpretation.
The problem here is to select a feedwater stop valve for a boiler
with a Maximum Allowable Working Pressure (MAWP) of 1500 psi.
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-39
Note that the design rules for a valve that is part of the boiler external piping are found in paragraph 122 of B31.1, Power Piping.
1.10.3.1 Solution to Design Exercise No. 3: The first step in
this problem is to determine the design pressure and temperature
required for this valve. According to paragraph 122.1.3(A.1) of
B31.1, the design pressure of a feedwater valve must exceed the
MAWP of the boiler by 25% or 225 psi, whichever is the lesser.
1500 psi + 225 psi = 1725 psi
1500 psi * 1.25 = 1875 psi
The design pressure PF is taken as the lesser value, 1725 psi. The
design temperature is found from paragraph 122.1.3(B) of B31.1
to be the saturation temperature of the boiler. That temperature for
a MAWP of 1500 psi is found to be 596°F from any steam table.
Thus we must now find a valve designed for 1725 psi at 596°F.
We next turn to the tables of valve materials and ratings from
the governing valve standard, ASME B 16.34, Valves—Flanged,
Threaded, and Welding End (for ready reference, these pages are
included at the end of this chapter). Assume the valve material is a
forging, SA-105, which is a carbon steel suitable for the relatively
low temperature of feedwater service. Notice that the standard uses
the ASTM designation A-105, rather than the ASME designation
SA-105 (it makes no difference in this case, because PG-11 permits
use of the materials in the ASME product standards accepted by reference in PG-42). It is seen from the Table 1 list of material specifications that A-105 falls in what is known as material group 1.1.
The task now is to find the lowest valve class adequate for the
design conditions we have established. As indicated in paragraph
2.1.1(f) of B16.34, ratings intermediate to tabulated values are determined by linear interpolation between temperatures. To simplify
this exercise, we will round up the design temperature to 600°F.
Turning to Table 2-1.1, the ratings for group 1.1 materials, we enter
with 600°F and look for a valve class adequate for 1725 psi. The
first such class is a 1500 (standard class) valve. However, an alternative choice is available from the ratings table for special class
valves. From that table, it is seen that a 900 special class valve
would also be adequate. (Note that the difference between the ratings of these two classes is based on the amount of NDE used in
their manufacture. The additional NDE required for special class
valves provides ensurance that critical locations are free of significant defects and justifies their higher pressure ratings.) The final
choice of valve then becomes one of cost and delivery time.
1.10.4
Design Exercise No. 4, Design of a Tube
for Lug Loading
PG-56 (which used to be in PW-43) provides a method for determining the allowable load on a tube lug. When PW-43 was revised in
1992, the sample problems in the Section I Appendix paragraphs A-71
to A-74, which illustrate the determination of allowable loading on
tube lugs, were revised to show the new method. Somehow, the explanation of the examples as printed was not as clear as the subcommittee
had intended, and the examples are a little hard to follow. Accordingly,
the first of the sample problems, that shown in A-71, is explained here
to serve as a guide to the method. The problem is described as follows.
A tube is suspended by a welded attachment with a 1500 lb design load and the dimensions shown in Fig. A-71 (shown below for
convenience). This is a condition of direct radial loading on the tube.
The allowable lug loading is calculated for the following conditions:
t Tube material is SA-213 T-22
t MAWP = 2258 psi
(Source: ASME SECTION I)
t Tube design temperature T = 800°F
t Tube diameter D = 4.0 in.
t Tube wall thickness t = 0.30 in.
t Lug thickness = 1/4 in.
t Lug attachment angle (the angle subtended by the lug width;
see Table PG-56.2) = 7 degrees.
t Design stress for tube at 800°F, Sa = 16,600 psi (increased
from its former value of 15,000 psi by the new stress criteria
adopted in the 1999 addenda).
1.10.4.1 Solution to Design Exercise No. 4: The first step in
the solution to this problem is to determine K, the tube-attachmentangle design factor, by interpolation in Table PG-56.2. K is found
to be 1.07. Also needed is the value of the variable X, which is
defined in PG-56.2. In this example,
X = bD/t2
where:
b = unit width = 1.0 in.
D = outside diameter of tube = 4.0 in.
t = tube wall thickness = 0.3 in.
X = (1)(4)/0.32 = 44.4
The load factor, Lf, is now determined either by reading it from
the plot in Fig. PG-56.2 or by using the appropriate load-factor
equation in PG-56.2(a) or PG-56.2(b), depending on whether the
lug is applying compression or tension loading to the tube. The
load-factor equations follow.
For compression loading,
2]
L f = 1.618 X [ -1.020 -0.014(log X )+ 0.005(log X )
For tension loading,
L f = 49.937 X [ -2.978 -0.898(log X )+ 0.139(log X )
2]
In either case, the load factor is a function of X, which has already been determined to be 44.4. It is hard to read the plot with
an accuracy greater than two significant figures (which ought to
be good enough for the design of a tube lug). However, if the
equations are used, greater accuracy can be obtained. Note that
the log terms in the equations are logarithms to the base 10. Substituting X = 44.4 in those equations gives a tension load factor
1-40 t Chapter 1
Lf = 0.0405 and a compression load factor Lf = 0.0326. The problem as stated concerns a tension load on the lug, but the values
of both load factors are derived to illustrate that there can be a
significant difference in allowable load, depending on the direction of the load.
The next step is to determine St, the amount of the allowable
stress that is available for the lug loading. St is found from the
equation in PG-56.2:
St = 2.0Sa - S
where:
Sa = allowable stress value from Section II, Part D, Subpart 1,
Table 1A = 16,600 psi
S = pressure stress in tube determined by the equation in
PG-27.2.1 = 15,000 psi
Thus, St is seen to be twice the allowable tube stress less the
membrane pressure stress, S, at MAWP determined from equation PG-27.2.1. (Notice that if there were no stress due to pressure,
the equation would give a value of St equal to twice the allowable
membrane pressure stress. This is not unreasonable because the
bending stress in the wall of the tube caused by lug loading is considered to be a secondary bending stress.) In the present example,
S is found to be 15,000 psi. Thus
St = 2(16,600) - 15,000 = 18,200 psi
EXCERPT FROM ASME B36.10M-2015 TABLE 1 USED IN DESIGN EXERCISE 1
EXCERPT FROM ASME B16.34-2013 TABLE 1 USED IN DESIGN EXERCISE 3
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 1-41
EXCERPT FROM ASME B16.34-2013 TABLE VII-2-1.1 USED IN DESIGN EXERCISE 3
CHAPTER
2
Section VII—Recommended
Guidelines for the Care
of Power Boilers
William L. Lowry and James T. Pillow1
2.1
INTRODUCTION - CHAPTER 2
ASME Section VII, Recommended Guidelines for the Care of
Power Boilers, falls within the purview of the BPV Committee
on Power Boilers (BPV I). The purpose of these Recommended
Guidelines, as stated in the “Organization of Section VII” is;
The purpose is to promote safety in the use of power boilers.
These guidelines are intended for use by those directly responsible for operating, maintaining, and examining power boilers.
The 2015 Section VII is the 2013 Edition reorganized, edited
and with new material added as a result of input from 30 Peer Reviewers and 10 additional volunteers. The primary discussion is
about industrial, gas or oil fired, watertube boilers, which constitute the vast majority of Power Boilers constructed. Other boiler
types are discussed in separate Articles. No information was discarded from the previous Edition.
The 2015 Edition of Section VII uses the term ‘examiner’ when
addressing the Owner-Operators personnel actions previously referred to as ‘inspecting’. The Boiler Code, Section I, identifies an
‘Authorized Inspector’ as the reviewer of work by a stamp holder
when fabricating, assembling and stamping a new boiler. After this
work is completed and the boiler has been placed ‘inservice’, the
National Board of Boiler Inspectors (NBBI) provides rules applying
to an operating boiler, repairs and alterations thereof. The personnel
trained by the NBBI and licensed by the Jurisdictions (States, Municipalities and Provinces) are called ‘inspectors’. The ‘Glossary’ of
Section VII has brief definitions of these terms and many other terms
that are used with regard to a boiler plant and its operation.
The five Subsections—1 thru 5—of Section VII discuss guidelines for safe, reliable operation as well as avoiding unsafe conditions in the power boilers.
1
Edmund W. K. Chang and Geoffrey M. Halley were the authors of
this chapter for the second and third edition that was initially authored by
Edmund W. K. Chang for the first edition. Fourth edition was updated by
James T. Pillow which is now completely revised by William L. Lowry.
– Editor.
Section VII and this Chapter 2 is written from the perspective of
Owner–Operators’ personnel experienced in operating, maintaining,
and examining industrial and utility power boilers. Certain parts of
this chapter are, in some instances, reiterations of Section VII Subsections, which was done to stress the importance of the information
already provided; in other instances, however, additional information
is provided where it is felt to be warranted. Where there are no comments on a section, the material is believed to have been covered sufficiently to not need additional clarification. The reader is suggested
to review existing literature, such as manufacturer’s instructions or
company procedures, for additional pertinent information.
Section VII, along with Section VI [1], contains recommended
practices and thus serves as a guideline. Consequently, it is considered a non-mandatory standard; however, Section VII does discuss
many activities that the Owner–Operator personnel must master
before a power boiler is commissioned. New personnel, who might
not be familiar with boiler operation, maintenance, and examination, can use Section VII as an introduction to these activities.
Experienced personnel, too, can use Section VII, for they will find
it to be a good periodic review of the essentials of power boiler
operation, maintenance, and examination.
Unlike how they treat other Sections of the ASME Boiler and Pressure Vessel Code, jurisdictional authorities do not adopt Section VII,
so consequently its use does not become mandatory. Nor does Section VII require interpretations (which are much-needed for the
other sections), for its relative user-friendliness enables any operator
of power boilers to use it in its present state. In light of the relatively recent emergence of the “on demand” power availability and
consumption requirements, particularly in the United States, many
large industrial boiler operators and also operators of utility size HRSG
boilers are shutting boilers off when not required, even when the
off cycle is for a relatively short period of time. This obviously can
significantly increase the number of operating cycles, often on boilers
that were not designed for highly cyclic operating conditions. This
changed mode of operation often results in fatigue type failures of various boiler structural elements. Experience has shown that the majority
of boiler failures are due to miss-operation in the field either due to
improper operator training, or a change in operating conditions, pressured by economics or environmental conditions.
2-2 t Chapter 2
Most U.S. jurisdictions and all Canadian provincial and territorial
jurisdictions have adopted certain ASME Boiler and Pressure Vessel Code Sections into law. Many have also become members of the
National Board of Boiler and Pressure Vessel Inspectors (NBBI, or
simply the NB). Typically U.S. and Canadian jurisdictions require
new boilers and pressure vessels to be registered with the NBBI and
repairs and alterations to be performed by holders of an NBBI Repair
Symbol Stamp (R-Stamp, or VR-Stamp in the case of pressure relief
valves). This means that all work performed on the pressure-retaining
parts of a boiler must be performed by accredited organizations using
approved material control and repair or alteration methods.
2.2
INTRODUCTION - SECTION VII
The ‘Organization of Section VII’ clearly states that the Section VII guidelines apply to power boilers that produce steam for
external use at a pressure exceeding 15 psig from the application
of heat, which may come from the combustion of fuels, from various hot waste gases, or from the application of electrical energy.
The guidelines apply to the boiler proper and to the boiler external piping as specified in the Code jurisdictional limits diagrams
in ASME Section I, Figs. PG-58.3.1a (given here as Fig. 2.1) and
PG-58.3.2 [2] or in ASME B31.1, Figs. 100.1.2(a) and (b) [3].
Furthermore, the reader should note that power boilers, as they
are applied in this guide, do not include Section I-type locomotive,
high-temperature water, and miniature boilers; Section III-type
nuclear power plant boilers; Section IV-type heating boilers
(recommended rules are covered in Section VI [1]); and Section
VIII-type pressure vessels; and marine-type boilers. The reader
should also note that once-through-type boilers are also not
included in the discussions. This chapter clarifies who should
use Section VII to enable users of excluded boilers to go to other
sources for the needed information.
Section VII guidelines do not address all of the details required
to operate, maintain and examine a power boiler. However, Section
VII does provide an overview of the activities necessary for safe,
reliable power boiler operation, maintenance, and examination. The
guidelines stress the importance of the checklist, of which those in
the Appendices are both helpful and essential to the boilers’ safe,
reliable operation, maintenance, and examination, and should be
adapted by all Owner–Operators for use in their own particular
installations. Owner–Operator personnel can become complacent,
believing that they will remember the required steps in any activity
without using a checklist—a bad habit, for it will in all likelihood
create serious consequences in the future. For example, if lessexperienced personnel are required to act as replacements for the
normal boiler operators, they are likely to overlook some crucial
item if they do not use checklists.
A checklist is a listing of required activities in which each
item is “signed off” as it is completed. Although a checklist is
not the procedure, it is as an important tool for ensuring that
repetitive procedures are done correctly by listing the sequence
of steps that must be followed. Many Owner–Operators have
assembled company procedures for the operation, maintenance,
and examination of power boilers. In some cases, however, the
company’s procedure book is kept at a location remote from
the operating personnel and is therefore not readily available
if needed. Ideally, these procedures should be under constant
review, updated whenever changes are made to the boiler
installation or operating system, and made readily available
to plant personnel. Nonmandatory Appendix A, ‘Checklists
for Maintenance Examinations’ is included in Section VII as
examples of the organization and detail of typical checklists.
Throughout Section VII, the reader is reminded to consult the
following:
(1)
(2)
(3)
(4)
(5)
(6)
manufacturer’s instructions;
the ASME Code Section I;
the National Fire Protection Association’s Codes;
the National Board Inspection Code (NBIC);
the Authorized Inspector or Insurance Inspector.
Other pertinent reference documents
A listing of all Section VII referenced documents and the
publisher of each is also provided in Article 202 of Section VII.
Many Owner–Operators are familiar with the Electric Power
Research Institute (EPRI). Some may be members of EPRI and
thus have access to its publications regarding boiler concerns. Of
these publications, some may be relevant to Section VII guidelines
for which an Owner–Operator requires additional information.
Many independent books have been published as guidelines that
cover the safe, reliable operation, maintenance, and examination of
power boilers. Unlike Section VII, however, these other guidelines
do not receive ongoing administration and updating, making
Section VII a logical first reference. Section VII was added to the
Boiler and Pressure Vessel Code in 1926 as a branch of Section I
and can be compared to an attachment operating manual or guide.
The title, “Recommended Rules for Care of Power Boilers,”
remained as such until the 1980s, when the word “Rules” was
replaced with the more appropriate word “Guidelines.” For many
years, a separate subcommittee existed to administer Section VII
with the greatest attention focused on large electric-generating
system boilers. However, with declining interest in Section VII, the
subcommittee became a subgroup of the Subcommittee of Power
Boilers (now BPV I) in the 1970s, with efforts made toward giving
attention to smaller boilers. Because the care and maintenance
practice of boilers changed little over the years, there was seldom
a need to revise Section VII. With the issue of the 1995 edition,
Section VII was no longer listed as a subgroup. Presently, Section
VII is still administered by the Section I Standards Committee
and is still issued with new editions of the Boiler and Pressure
Vessel Code. The 2015 Edition of Section VII is a reorganized and
updated presentation, containing all the previous information as
well as some new information.
Deregulation trends in power generation and greater permitting
and citing difficulty of new plants add additional problems for
Owner–Operators. The need to extend the life of existing boilers
requires renewed emphasis in generating assets management and
care of the power boilers. The task of the Section I Standards
Committee is directing the preparation and inclusion in Section
VII of new technology and trends such as heat recovery steam
generator (HRSG) and solar boiler provisions.
The five Subsections—1 thru 5—of Section VII are reviewed
individually in this chapter to explain the reasons for which each
subsection exists.
The user of these guidelines should note that throughout this
review, ASME Section I, “Rules for Construction of Power
Boilers” [2], provides rules for the construction of power boilers,
whereas the National Board Inspection Code (NBIC) [4] provides
rules for boilers already placed into service.
The reader of this chapter should particularly note the first few
sentences of each Article and section, for they preface the basic
information to follow.
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 2-3
FIG. 2.1 CODE JURISDICTIONAL LIMITS FOR PIPING: DRUM-TYPE BOILERS (Source: Fig. PG-58.3.1(a), Section I of the
2015 ASME B&PV Code)
WATERTUBE DRUM-TYPE INDUSTRIAL
STEAM BOILERS-SUBSECTION 1
2.3
FUNDAMENTALS OF WATERTUBE
BOILERS - ARTICLE 100
Although it is obvious that this brief Subsection 1 does not
cover everything relative to Watertube Industrial Steam Boilers, it
does attempt to introduce the Fundamentals of Watertube Boilers
(Article 100), the principals of Boiler Operation (Article 101),
the associated Auxiliaries (Article 102), Appurtenances required
by Section I (Article 103), Instrumentation necessary (Article
104), Examinations to be performed by boiler operators and
staff (Article 105), and the requirements for Repairs, Alterations
and Maintenance (Article 106). Where additional information is
needed, the user should consult such resources as the boiler and
equipment manufacturer’s installation, operating, and maintenance
2-4 t Chapter 2
manuals. It should be noted that if a variance exists between the
equipment manufacturer’s instructions and any other reference, the
normal practice is to follow the manufacturer’s instructions.
It is important that the boiler is operated in the manner for which
it was designed. For example, a boiler which has been designed for
baseload operation (steady state) may well suffer from fatigue type
problems if operated in a cyclic fashion (swing loaded) or nightly
shutdowns and morning restarts, due to varying thermally induced
operating stresses. It is therefore important that the boiler owneroperator and the manufacturer each have a clear understanding of
the manner in which the boiler is going to be operated if problems
are to be avoided down the road. Similarly if the operating mode
of an existing boiler installation is to be changed significantly
for reasons of economy or environmental concern, then it would
behoove the owner-operator to advise the manufacturer and seek
assistance in minimizing any operational effects that may impact
on boiler life or reliability.
2.3.1
Boiler Types
The Fundamentals Article 100 states that there are three basic
types of power boilers—watertube (this Subsection), firetube
(Subsection 3, Article 300), and electric (Subsection 3, Article
301)—and that these are the types that most operators will be
involved with at some time during their careers. Thus, operators
should be familiar with how the components differ between
the three boiler types to understand their functions and also
to communicate intelligently with other personnel. The three
types can be further classified as either package boilers or fieldassembled boilers; firetube and electric boilers as well as the
smaller watertube boilers comprise the package boiler population,
whereas most field-assembled boilers are the watertube type.
Many references are available for readers to familiarize themselves
with the different boiler and system components so that they may
perform the operation, maintenance, and examination functions in
a safe, reliable manner.
The Subsection 3, Article 300 provides the basic facts concerning
firetube boilers that include the following:
(1) common use is for small capacity, low-pressure applications in industrial process plants;
(2) they are available in either dryback (refractory) or waterback construction;
(3) combustion gases pass through the inside of the tubes, with
water surrounding the outside of the tubes; and
(4) they make applying superheaters (when required) more
difficult.
Advantages of this boiler design include its simple construction
and less rigid water treatment requirements. Disadvantages include
the excessive weight of the boiler and contents per pound of steam
generated, the excessive time required to raise pressure because of
the relatively large volume of water contained within the boiler,
and the inability to respond quickly to load changes because of that
relatively large volume of water. See Fig. 2.2 for a typical firetube
boiler layout.
The various types of electric boilers are discussed in Subsection
3, Article 301. Electric resistance heating coil boilers are very-lowcapacity boilers. The basic facts regarding the other type of electric
boiler (the electrode type) include the following:
(1) they use boiler water conductivity to generate the steam;
(2) the insulators supporting the electrodes must be cleaned or
replaced periodically;
FIG. 2.2 TYPICAL FIRETUBE BOILER LAYOUT (Source: EASCO Boiler Corporation)
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(3) high voltages (up to 16 kV) may be used;
(4) protection is needed for ground faults, over current, and
loss of phase.
It should be noted that for item (1) of the preceding list,
depending on the design of the electrode boiler and the working
voltage, the water conductivity required may be very high or
very low, making it imperative that the boiler manufacturer’s
specifications be adhered to.
Watertube boilers discussed in Subsection 1 comprise most power
boilers as well as the majority of the larger high-pressure industrial
and utility boilers. Basic facts include the following:
(1) water flows inside the tube and the combustion gases flow
on the outside;
(2) lower unit weight of boiler per pound of steam generated;
(3) less time is required to raise steam pressure;
(4) greater flexibility for responding to load changes;
(5) greater ability to operate at high rates of steam generation;
and
(6) close control of boiler water chemistry is required.
Throughout the rest of the Section VII Subsections, the reader
should remember that the circulation of water through a natural
circulation boiler depends solely on the difference in the weight of
the steam–water mixture in the generating or waterwall tubes and
the weight of the water in the downcomers. Section VII, Figure
100.2-2 (Steam Drum with Tubes) is a basic diagram showing
a simple natural circulation loop and is presented as Fig. 2.3 in
this chapter. As the water is heated in the generating or waterwall
tubes, steam bubbles are formed and the heated steam-water
mixture rises through the tubes from the force of the weight of the
denser, unheated water in the downcomers, thereby establishing
circulation.
Considering the natural circulation concept applied to actual
conditions, take for example an older tangent-tube waterwall
boiler. The waterwall tubes’ fireside surfaces should not be covered
with any refractory to repair or prevent hot spots caused by the
deteriorated outer sealing refractory. If refractory is applied on the
fireside surfaces contrary to original design, the natural circulation
in the refractory-covered tubes may be affected, possibly leading
to deposit buildup in sloped tube sections and to problems with
tube expansion and contraction and causing damage at the tube-toheader connections.
Another example is a boiler in which the outer insulation has
fallen out in places and the condition is neglected rather than
repaired. By understanding the fundamentals, it is obvious that the
natural circulation may be adversely affected. If the insulation is
missing in the upper areas, cooling may occur, making the fluid
inside the tubes heavier. In addition, for tangent-tube waterwalls
the covered tube may expand and contract differently from
adjacent uncovered tubes—a difference that, if the tube-to-header
connections are rolled and seal-welded, may cause the connections
to loosen. The boiler operating personnel must be aware that the
natural circulation flow rate will differ throughout the boiler. This
is especially helpful when evaluating boiler tube failures. The
longer water flow circuit with multiple tube bends will definitely
have less flow. This will promote deposit formation inside the
tubes and most likely resulting in tube metal overheating.
In Article 104, further emphasis is placed that the required level
of water must be maintained in the steam drum at all times. An
unacceptably low steam drum water level can reduce the natural
circulation flow rate to a level that may cause the generating or
waterwall tubes to overheat. National Board Statistical data on
the causes of boiler accidents spread over many years shows that
failure of the low-water fuel-cutoff device from lack of proper
maintenance is the most common cause of boiler accidents. The
low-water fuel-cutoff device must be maintained in good working
condition on all types of boilers to ensure that, while the boiler is
operating, the water level does not drop to an unsafe level. This
fact should be remembered when the reader reviews other Articles
that cover water level.
The importance of the steam drum of watertube boilers in
separating the steam from the steam-water mixture will be
more easily understood after reviewing the steam drum crosssectional views in Section VII, Figs. 100.2-3 and -4 (Steam Drum
Internals), which are given here in this chapter as Figs. 2.4 and
2.5, respectively. Of all the different watertube boiler components,
the steam drum has the most parts, of which the design differs
from manufacturer to manufacturer. Operating and maintenance
personnel must understand the function of each part to effectively
operate, maintain, and examine a power boiler. In some designs,
the crawl space is so tight that the drum internal parts should be
removed during each overhaul outage to ensure that the internal
parts near the middle of the drum are not loose, defective, or
missing.
FIG. 2.3 NATURAL CIRCULATION FOR STEAM DRUM WITH TUBES (Source: 100.2-2, Section VII of the 2015 ASME B&PV
Code)
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FIG. 2.4 STEAM DRUM INTERNALS: BAFFLE-TYPE (Source: Fig. 100.2-3, Section VII of the 2015 ASME B&PV Code)
The steam drum is also a critical element of boiler internal
examination. During firetube boiler inspections, the shell, furnace,
tubesheets, and the rear waterwall of water-backed boilers are
important examination areas. By inspecting inside the steam- and/
or mud drums of watertube boilers, or inside the shell and outside
the furnace and flue tubes of firetube boilers, a good assessment
of boiler water chemistry (or treatment) is obtained. Access must
be provided for a thorough examination to be made in all the
aforementioned areas.
Feedwater enters the steam drum below the normal water level.
In most watertube designs, the feedwater is directed toward the
downcomers to minimize the flow of steam bubbles to them, which
would reduce the head available to maintain natural circulation.
If the incoming feedwater enters at the ends of the steam drum
without a distribution system, the feedwater somehow has to be
able to distribute evenly throughout the drum length to ensure that
downcomers have nearly equal amount of water to circulate. This
and maintaining proper water level will help ensure good circulation
is established to prevent overheating. In firetube boilers feedwater is
directed along the inside of the shell away from any heated surfaces,
which minimizes the possibility of any damaging thermal effects
caused by cool-water impinging on the hot furnace or flue tubes.
Another example to show why maintenance and examination
personnel should be familiar with the different boiler parts is that,
in certain steam drum designs, several small nozzles come off the
feedwater pipe and are directed downward toward the downcomers.
Sometimes the maintenance personnel did not remove the internals
for access and so did not know that some of these nozzles were
FIG. 2.5 STEAM DRUM INTERNALS: CYCLONE SEPARATOR–TYPE (Source: Fig. 100.2-4, Section VII of the 2015 ASME B&PV
Code)
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 2-7
missing; in other cases, the maintenance personnel did not
understand the function of these nozzles and therefore did not list
the missing nozzles on a punchlist.
The steam drum deflection baffles are another component
used to aid in separating the steam from the steam-water mixture
that enters the drum with which the operating, maintenance,
and examination personnel should be familiar. As the steamwater mixture enters the steam drum from the heated risers, the
deflection baffles help separate the water from the mixture by
directing the water to the downcomers as free of steam bubbles as
possible. These deflection baffles are designed so that individual
pieces can be passed through the drum manhole for removal or
replacement. The pieces are held in place by brackets, welded
studs, and acorn-type nuts—the latter covering the ends of the
studs to slow the corrosion process. Many parts are needed, all of
which should be in good condition. Maintenance and examination
personnel should be fully aware that loose parts can break away,
causing flow restrictions or preventing the proper separation of
steam and water. The basic criterion is that the boiler’s natural
circulation is aided by keeping the steam separate from the water
inside the steam drum. Additional information is helpful here or
in section Article 103, section 103.5 Boiler Blowdown to add to
an examination checklist that the continuous blowdown piping
(CBD) shown in Fig. 2.4 should be examined to ensure that the
pipe holes are in the correct orientation and spaced properly.
Examination personnel should be wary that the pipe holes are
normally positioned at the top of the pipe so deposits are not
sucked in to the CBD pipe, but collect on the bottom to be drained
out. The piping should be cleaned out during outages. Obviously,
this aids in the boiler water chemistry to control conductivity and
deposits.
If chemical feed piping is provided, the pipe holes orientation
and spacing also needs to be checked along with holes plugging.
The holes are normally placed on the underside of these pipes.
2.3.2
Economizers and Superheaters
Some may argue that the economizer is not a part of the boiler
because, in firetube boilers and packaged watertube boilers, the
economizer is a separate piece of equipment. However, in many
watertube boilers, it is made of bundled tubes and is supported
similarly to the superheater—usually within the boiler enclosure.
See Fig. 2.6 Typical Economizer.
Starting up an economizer is not discussed in Section VII. Three
items when “Placing in Service” are worthy of discussion:
(1) steaming during start-up,
(2) thermal shock, and
(3) severe external corrosion.
FIG. 2.6 TYPICAL ECONOMIZER (Source: Fig. 100.4-1 Section VII of the 2015 ASME B&PV Code)
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Steaming is inherent to the economizer. Steaming can occur
during start-up, if the feedwater flow is low or nonexistent.
Moreover, feedwater is not normally added to the boiler during
its initial start-up, so there would not be any flow through the
economizer. The hot start-up gases pass the economizer and may
form steam inside the tubes that pass to the steam drum, leaving
vapor spaces in the economizer. Once the feedwater pumps
start flowing water through the economizer, water hammer may
result and possibly cause damage. To avoid water hammer, an
economizer-recirculating line is installed from the boiler’s lower
water space to the economizer inlet header, which will prevent the
formation of any pockets or vapor spaces that steaming may tend
to create and also prevent damaging water hammer from occurring
when the feedwater line flows.
Thermal shock is also inherent to the economizer. It can occur
due to the hot and thick economizer inlet header as it is being fed
colder feedwater. Design wise, not much can be done to prevent
thermal shock except to examine for cracking during outages.
Examinations are focused on the feedwater inlet area of the
economizer inlet header. Operating personnel should be aware
that economizer thermal shock problems are possible whenever
feedwater heaters must be taken out of service because of feedwater
tube leaks.
Severe external corrosion is possible whenever the fuel is laden
with sulfur, vanadium, iron, and sodium. The theory is that sulfur
and sodium combine at temperatures typical of the convection pass
to form a sticky deposit on the economizer surfaces. Vanadium
in the sticky deposit helps to catalyze sulfur dioxide (SO2) into
sulfur trioxide (SO3). Moisture from leaks or residual boiler
washwater will combine with the SO3 to form a corrosive acid,
so obviously any leaks in and around the economizer should be
repaired immediately. During the boiler wash, a neutralization
process should be considered to minimize residual boiler washwater reacting with the SO3.
Superheaters are tubular heat transfer surfaces used to increase
the steam temperature after the steam has exited the drum of a
watertube boiler. Steam inside the tubes is heated as the combustion
gas passes over the outside of the bare or extended surface tubes.
The final-pass superheater is located at the boiler furnace exit
where the gases of combustion are hot enough to achieve the final
steam temperature desired.
Superheaters may be drainable, but many are “pendent”
configuration and not drainable.
Manufacturer’s instructions should be followed when starting
boilers with economizers and or superheaters.
2.3.3
Combustion
Article 1, sections 100.6 and 100.7 reviews the following basic
requirements for combustion: fuel, oxygen, and heat. Coal, oil, and
gas are the most common fuels used in boilers.
Although nonflammable, oxygen is needed to support the
combustion of fuels. (Air is approximately 21% oxygen and 78%
nitrogen.) One should remember that even though nitrogen carries
away heat and makes no contribution to the overall combustion
process, it does react with oxygen to form nitric oxide (NOX)
compounds that are limited by environmental regulations. More
air for the combustion beyond the excess air recommendations of
burner manufacturers normally reduces boiler efficiency. Heat is
required to raise the fuel to its kindling or ignition temperature.
Probably the most useful information covered in these sections
is the discussion about oil and the need for maximizing the fuel
surface area exposed to air for faster, more complete burning. The
combustion of coal is improved by crushing or grinding the coal
into small particles and by creating turbulence with the air supplied
to thoroughly mix the fuel and air (See Subsection 3. Article 401).
The combustion of oil is improved by atomizing the oil into a very
fine mist and by creating turbulence with the air supplied, again to
promote thorough mixing. Fuel oil is atomized either mechanically
with the high-pressure drop across the oil-gun tip or by using steam
or air to create an emulsion that is then subjected to a shearing
action at the nozzle tip.
These sections provide only the very basic information about the
combustion process. The reader should consult other references to
fully understand the process.
2.3.4
Boiler Efficiency
Boiler operators should understand the fundamentals of boiler
efficiency, particularly as fuel prices increase, and they can optimize
fuel usage by knowing what factors affect boiler efficiency. Stack
losses are the predominant factor affecting boiler efficiency. Stated
simply, boiler efficiency is dependent on how much of the heating
value of the fuel is lost as either sensible heat or by incomplete
combustion. Sensible heat loss is the heat content of the various
stack gas components (primarily nitrogen, carbon dioxide, oxygen,
and water vapor) that, upon traveling up a stack, are lost to the
atmosphere—losses that may be caused by the oversupply of
excess air, by moisture in the fuel, or by humidity in the air.
It is important to remember that (as stated previously) air is
about 78% nitrogen and 21% oxygen. Nitrogen does not support
combustion; it travels up the stack with any unused oxygen and
helps to cool the boiler flame. The more excess air, the more heat
nitrogen traveling up a stack takes with it. Moisture in the fuel,
enhanced by ambient air humidity, becomes superheated steam
produced as the fuel burns; it too is lost to the atmosphere upon
traveling up the stack. This section briefly mentions that hydrogen
in this moisture also combines with available oxygen, to form
superheated steam, which makes less oxygen available for the
combustion process. This steam travels up the stack with the heat
normally used for the water in the tubes.
The cleanliness of boiler tubes both inside and out and of air
preheaters whether tubular or regenerative affects boiler efficiency.
External cleaning of watertube boiler tubes is performed with
timely sootblowing. Steam sootblowing should only be done when
necessary. Excessive steam sootblowing will lead to an over use of
steam requiring additional water makeup and heating. Maintaining
clean watertube boiler tube interior is accomplished with proper
boiler water chemistry and occasional cleaning either chemically
or mechanically.
Another contributor to the loss of fuel heating value is incomplete
combustion. The subsection states simply that poor mixing of fuel
and air causes it, as does a lack of sufficient air supply. Poor mixing
in oil-fired boilers may be attributed to poor atomization and the
poor mixing action of the fuel and oxygen. A sufficient supply of
air (which denotes a sufficient supply of oxygen) means a delicate
balance of air. Too little air produces unburned hydrocarbons and
may cause flame instability, whereas too much air may allow an
excessive amount of heat to be lost up a stack into the atmosphere.
Including more basic information is helpful to understand
why a component is important. This information is helpful here
or in section 102.2, Oil Systems. For example, the flames of oilfired burners must provide as complete combustion as possible.
Optimum flame condition of traditional burners is affected by
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 2-9
conditions of atomizer and refractory throat, position of the
air register or damper, and orientation of swirlers or stabilizers.
See Fig. 2.7 Simple Circular Oil Burner. The atomizer helps
break down the oil into smaller particles for the mixing with
air. Atomizers wear out and need to be replaced regularly. The
bell-mouth shaped refractory throat help create the aerodynamic
conditions for proper flame shape and combustion. Deteriorated
refractory or incorrect throat contour and dimensions will affect
flame shape and satisfactory combustion and should be examined
regularly. The air register or damper delivers air into the burner
with the desired amount of rotation and velocity and helps control
the flame shape. Throttling the air register door produces a higher
rotary velocity of air through the burner, increases the rapidity of
combustion and tends to shorten the flame. The swirler or stabilizer
further creates rotation of air around a turbulent flame resulting
in laminarization of the jet flow and improves flame stability.
Understanding the function of the components will help the boiler
operator recognize why the components must be in satisfactory
condition and properly installed for optimum boiler efficiency.
Although not mentioned in Section VII, the heat rate is commonly
used to measure efficiency in power generating plants-a measure
that simply determines how much energy or fuel must be burned
to produce a certain amount of electrical energy that can be sold.
The units of heat rate are measured in Btu/kWh. This efficiency
performance pertains to the power plant, not just to the boiler.
Industrial boiler efficiency is typically expressed as output divided
FIG. 2.7
by input. The ASME Performance Test Code PTC 4, “Fired Steam
Generators,” covers the testing methods.
The Fundamentals subsection provides basic information that
fosters thinking and helps to explain why and how power boiler
components function.
2.4
BOILER OPERATION—ARTICLE 101
This may be the most useful Article for boiler-operating
personnel. Despite the title, however, maintenance, examination,
and engineering personnel will also find reading this article to be
of value—either as new knowledge or as a refresher for existing
knowledge.
Again, the reader is reminded that one purpose of Section VII
is to help the Owner–Operator achieve safe, reliable power boiler
operation. This Article provides boiler-operating procedures for
industrial watertube boilers, but it can also be applied to other
boiler types to help provide safe, reliable operation. It is stressed
that training, written procedures and checklists should be developed
and used by operating, maintenance, and examination personnel.
This Article provides most of the information necessary to
develop step-by-step boiler-operating procedures for the individual
stages of operation. The “Preparing for Operation” section
provides just a sampling of the checklists throughout Section VII:
for example, “Safety Checklist for Examination,” “Water-side
SIMPLE CIRCULAR OIL BURNER
2-10 t Chapter 2
Checklist,” “Fire-side Checklist,” and “External Checklist.” The
other sections of ‘Boiler Operation’ Article 101, although they lack
the title “Checklist,” can also be easily adapted for checklists used
by operating, maintenance, and examination personnel.
Because of the heavy volume of information to remember in
the safe, reliable operation of a boiler, relying on memory alone
would be foolish. It is hoped that boiler operator readers will
review existing procedures, or else develop their own procedures
and checklists after they review Section VII.
2.4.1
Operator Training
Some jurisdictions require qualified boiler operators or competent attendants of power boilers. As a minimum to be qualified,
the operator may be required to be familiar with the Section VII
contents. As the Boiler Operation Article and the rest of Section
VII are reviewed, the reader will see that valuable information is
provided for safe, reliable power boiler operation, and will also
see that the Section VII contents can be adapted to develop boiler
operator training courses and examinations.
The Operator Training section is short and clearly written. Safe,
reliable operation does depend largely on the skill and attentiveness
of the operating personnel. In some plants, the operating and
maintenance personnel can be the same persons. Operator training
and retraining is a must, and operator attitude must be one of
attentiveness.
Operator training should include a knowledge of fundamentals
such as that which is presented in the Fundamentals Article. To have
an appreciation of his or her job, and also for the encouragement of
attentiveness, the operator should understand why certain functions
are required to be performed—an understanding that may help
prevent accidents or damage to the boiler. Operator training should
also include familiarity with equipment, in which one’s knowledge
will develop with on-the-job experience and periodic refresher
training, and one’s pride in work and attentiveness is fostered.
This Article reminds the user that following the manufacturer’s
instructions enhances his or her operating and maintenance skills.
Some manufacturers issue periodic service bulletins to alert the
Owner–Operator of experiences indicating that modifications
or corrections to his or her equipment may be necessary. Plant
supervisors should ensure that these changes are communicated to
operating and maintenance personnel. It is particularly important
that product-recall bulletins on component parts be directed to the
appropriate personnel and then followed. Many reference books
have been written about boiler operations, and interactive computer
programs have been developed to assist with continuous training.
Written procedures prepared before and during the commissioning period are of special importance. As was stressed previously, procedures and checklists are extremely important for
all stages of boiler operation, but just having them is not enough;
the procedures and checklists must be used and revised whenever
necessary. Unfortunately, many procedures and checklists are
published into books that are rarely used. It is recommended that
a periodic review of operating procedures be handled in the same
way that safety programs are handled.
Safety training and refresher training classes become mandatory
to help ensure that personnel will be conditioned to practice safe
work habits and to show regulators that the company is serious
in preventing workplace accidents. Unless there are laws with
serious consequences to lawbreakers specific work practices,
such as following operating procedures and use of checklists, will
usually not be practiced. In addition, as with safety programs, at a
minimum a review of operating procedures should be performed
annually with quizzes included to encourage attentiveness and to
demonstrate that an ongoing training program is established for
the record.
2.4.2
Other General Guidelines
This section continues with reminders and includes precautions
covered in more detail in subsequent subsections. Here again these
precautions should be covered in the Owner-Operators’ procedures
and checklists. To prevent explosions, there is a constant reminder
for one to purge the fireside of the boiler, during which the proper
water level and the proper furnace pressure must be maintained.
Clearance for boiler expansion must also be maintained.
Section 101.1.4, Maintaining Proper Furnace Pressure, mentions
that boilers with positive pressure furnaces have furnace pressure
varying from 5 in. to 25 in. of water (1.3 kPa to 6.2 kPa) as the boiler
operates from minimum to maximum, and that design pressure of
furnaces rarely exceeds 28 in. of water (6.9 kPa) because of the cost
of reinforcing the furnace wall support system. Boiler operators can
be misinformed when changing their alarm and trip setpoints for
high furnace pressure. The boiler manufacturer specifications may
state that the furnace is designed to withstand an internal pressure
(furnace design pressure) of 26.5 in. of water (6.6 kPa) gage with
no permanent deformation of the furnace buckstay system and as
recommended by the National Fire Protection Association (NFPA)
standard NFPA-85, Boiler and Combustion Systems Hazards
Code. The boiler operator may be confronted with the nagging
problem of high furnace pressure caused be dirty air preheater
baskets and believe that he can change the high furnace pressure
trip setpoint to as high as 26 in. of water (6.5 kPa). However, they
may be unaware that the boiler manufacturer’s design terminology
may have a different meaning.
For one boiler manufacturer the furnace design pressure is really
the furnace yield point. They design the furnace with a margin of
safety between expected maximum operating furnace pressure
and the pressure at which the furnace begins to yield and suffer
permanent deformation, which may be 60 percent of the yield
point. The boiler operator should, therefore, follow a trip setpoint
of 16 in. of water (4.0 kPa) or 60 percent of 26.5 in. of water
(6.6 kPa) (furnace yield point).
According to design practice, the furnace yield point must be
at least equal to or greater than the forced draft (FD) fan capacity.
If the FD fan capacity is 26.5 in. of water (6.6 kPa), the furnace
yield point must be at least equal to this to withstand the maximum
pressure the FD fan can supply. However, this is not a safe operating
pressure. For example, in a worst-case situation of a “run-awayfan,” the unit must trip long before the yield point or possibly suffer
permanent damages to waterwalls and points beyond. In addition,
since control systems may not function instantaneously it would be
risky to have the trip setpoint so close to the furnace yield point.
Before changing high furnace pressure alarm and trip setpoints,
the boiler operator must know and understand the furnace design
practices and the risks.
A general list of reference resources is provided in section 101.1.6
for use as power boiler guidelines. In addition to the documents
and organizations listed in those references, persons with access
to EPRI and NBBI literature may find the information provided
by these organizations highly useful. This section reminds readers
that most types of operational problems have previously occurred
and that certain problems can be avoided by learning from the
combined knowledge and experiences of these resources.
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2.4.3
Preparing for Operation
Once the new power boiler is erected or installed, and inspections are complete in accordance with ASME Section I by an
Authorized Inspector, it is time for one to prepare for its operation.
This section provides the checklist format to ensure that nothing
is missed before the fires are started. The first reminder is related
to jurisdictional inspection requirements; states (U.S.), provinces
(Canada), and some cities have different inspection requirements,
for some follow the provisions of the NBBI, others require
installation permits, and still others require operating permits.
The reader should note that a permit is generally required from
the local air pollution control authority before the commencement
of construction or installation, and as one of the first steps in
preparing for operation, the responsible Owner–Operator must be
knowledgeable of local jurisdictional requirements. In most cases,
the Authorized Inspection Agency will assist the Owner–Operator
with the inspection and permit requirements.
The next reminder is chemical cleaning. (Internal cleaning is
also covered in Subsection 2, section 200.2 “Internal Cleaning of
Boilers.”) For new power boilers, both alkaline boilout and solvent
(acid or base) cleaning is necessary. The alkaline boilout is for
removing grease and oils; the solvent cleaning, for removing rust
and mill scales.
Section VII does not mention steam blowing as one of the
preliminary steps. New boilers with separate superheat or reheat
sections usually include steam blow to remove manufacturing
mill scale and erection debris in these steam circuits to prevent
damage to downstream components such as the turbine. For inservice boilers when superheat and reheat tube replacements are
required, steam blow may or may not be necessary depending on
the confidence in the fabricator and erector leaving the tube free
of debris.
The following are brief synopses gathered from the preoperational checklists presented in this section. Readers are reminded
to pay particular attention to the details of this section, for the
information as provided is good for training. These preoperational checklists are preludes to the discussion in Article 105,
“Examinations.”
Safety Checklist for Boiler Examination—for the safety of
examination personnel entering the boiler. Part 2, Inspection,
of the NBIC provides useful guidelines to follow that consider inspection to be the primary business of the NBBI, and
it also stresses the importance of lockout and tagout procedures [4].
Waterside Checklist—to ensure that the accessible internals
are free of erection and/or manufacturing debris, with the
inclusion of precautions related to relocated or inservice
power boilers. The checklist includes examining the inside of
steam- and mud-drums for deposits, loose or missing parts,
and erosion-corrosion. In addition, similar comments apply
to the shell internals of firetube boilers.
Fireside Checklist—to cover the examination of ducts, flues,
furnaces, windboxes, and vestibules. The discussion includes
looking for overheating in relocated or inservice power boilers. Common areas to examine are given as well. Dirty boilers or internal tube deposits at high-heat flux areas or where
burner flame impingement can occur can be examined visually by using a flashlight beam directed parallel to the outside
of the tube surfaces, or they can be examined by touch (e.g.,
sliding the hand over the tube surfaces to feel for bulges or
blistering along the fireside surfaces). The noting of defects
during examination is stressed rather than relying on memory
until the end of the examination.
External Checklist—for use especially with new power boilers. The examination includes, for example, ensuring that free
access to burner equipment exists, as well as removing any
temporary shipping or construction restraints, verifying free
expansion, verifying that all instrumentation and controls are
operational, and checking that personnel protection from hot
surfaces is provided. When saying that “Piping should be free
to move from cold to hot position,” operations and maintenance personnel should be aware that any high energy piping,
such main steam piping, should be floating, except at the designated rigidly supported areas. Routine examination of the constant and variable spring supports should indicate no topped or
bottomed out conditions of the spring supports. Pressure relief
valve outlet guidelines are also provided, for the outlet part
of the pressure relief valve is not designed to hold the pressures seen at the inlet, thereby necessitating precautions when
attaching the discharge piping. The rule provided here is that
the pressure relief valve should not support a weight exceeding the weight of a short elbow and drip pan or a comparable
weight, and when one is in doubt, he or she should consult the
pressure relief valve manufacturer. For pressure relief valves
outdoors, wind load can add stress to the valve, especially if,
the discharge piping exceeds the short elbow and drip pan criteria. The proper location of the pressure relief valve discharge
away from potentially deleterious positions (i.e., where it could
cause injury or property damage) is also stressed.
The subject of hydrostatic testing completes the Preparing for
Operation section. It should be remembered that all jurisdictions
do not follow the same rules. For example, jurisdictions who have
adopted ASME Section I requirements for new construction [2]
may or may not have adopted the NBIC requirements for existing
boilers [4]. Therefore, the boiler operator must first be aware of his
or her jurisdiction’s requirements. ASME Section I requirements
apply to new construction or new boilers, whereas the NBIC
requirements apply to inservice boilers. When the boiler passes
the hydrostatic test and the manufacturer’s data report is signed by
the Authorized Inspector, repairs become the responsibility of the
NBIC [4]; however, for both Section I and the NBIC, usually an
Authorized Inspector is required to witness the initial hydrostatic
testing. Where permitted by the jurisdiction, the boiler operator who
holds an NB Owner/User Inspection Organization accreditation
may permit his or her NB Owner/User Commissioned Inspector
to witness the hydrostatic testing after weld repairs are completed.
This section recommends that new power boilers be subjected to
a hydrostatic test of 1.5 times the design pressure. However, for a
boiler in service for an extended time period, such a hydrostatic test
is unreasonable because of advanced age and normal deterioration.
A provision of Part 2, Inspection, of the NBIC addresses use of a
pressure test at the discretion of the Inspector. The method used for
the test is to be as agreed by the owner-user and the Inspector. This
provision goes on to say that pressure tests for repairs or alterations are
to be in accordance with Part 3, Repair and Alterations, of the NBIC.
It should be noted that the purpose of the initial hydrostatic test prior
to stamping a new boiler is to verify component tightness and to check
for gross design errors; it is not a proof test. Hydrostatic leak tests
subsequent to the initial stamping are for leak tightness only.
2-12 t Chapter 2
This section defines the normal, good practices in preparing for
the hydrostatic test, such as using new gaskets and ensuring that the
pressure gage has been recently calibrated. For pressure relief valves
welded in place on high-pressure boilers, either gags or hydrostatic
test plugs are recommended. The use of test plugs for high-pressure
boilers over 2,000 psig design pressure is recommended here
because of the possibility of misapplied gags damaging the pressure
relief valve seat or spindle. It is recomended that gags not be fully
tightened until the hydrostatic pressure reaches 80% of operating
pressure—the same recommendation given for inservice testing
of pressure relief valves to prevent damage to the seat and spindle
caused by thermal expansion. (Pressure relief valves are covered in
more detail in Article 103, “Appurtenances.”)
The Testing section discusses water temperature; the use of
deaerated, distilled, or demineralized water in non-drainable
sections; the venting out of all air; the examining during the test;
and the returning of the boiler to its normal operating condition
after the test. The reminders provided in this section are useful and
appropriate as items for a checklist.
ASME Section I [2] specifies that the water temperature
should not be less than the ambient temperature, but in no case
should it be less than 70°F. This minimum temperature prevents
a brittle fracture failure during the pressure test and, to a lesser
degree, minimizes any false leak indications from atmospheric
humidity induced metal “sweating.” A maximum temperature of
120°F is specified for the safety of the examiners during close-up
examinations if any leaks should occur.
It is noted that all air should be vented or removed from the
system before applying pressure. Air is compressible; as such, air
in the system will make applying and holding the test pressure
difficult. Safety is also a concern, for compressed air can be
explosive and dangerous to those performing the examination.
This section reminds the reader of an often neglected or forgotten
fact: that ASME Section I, PG-60.3.7, specifies that shut-off valves
between boiler and gage glasses be locked or sealed open [2].
PG-67.3.7 goes on to explain that the valves need not be locked
and sealed open under certain conditions: the boiler maximum
allowable working pressure (MAWP) does not exceed 250 psig
(1.7 MPa); the boiler is not hand fired or fired with solid fuel in
suspension; the burner control system stops fuel supply and firing
if the valves are not in the open position; and the minimum valve
size is NPS 1. This specification is obviously attributed to the high
importance of water level, especially if the remote level indicators
should fail.
Another useful reminder pertains to the main steam-stop valve
stem being eased up just enough to reduce thermal expansion
stresses. This information may be applied to repairs when a valve
is welded and the welds are heat-treated. Some maintenance
personnel may be unaware of what is required: for example,
leaving the valve seat and stem closed may damage them.
The discussion moves in sequence from “Establishing Water
Level,” to “Light-Off,” and to “Going On-Line.” The boiler operator can develop written step-by-step start-up procedures from
the information provided. If the boiler operator already has such
procedures, the information provided here can be used as a comparison to possibly improve existing procedures.
A basic “Establishing Water Level” procedure to which details
can be added includes the following:
2.4.4
There is a reminder in this section that the water temperature
should be as close as possible to the drum and header metal temperatures to protect the thick-walled drum from excessive temperature stresses and also to prevent leaks in rolled-tube joints.
The boiler manufacturer specifies the temperature deviation limits:
for example, 100°F (38°C) between drum top and bottom and/or
100°F (38°C) between inside and outside surfaces of the drum. The
procedure must follow the boiler manufacturer’s requirements.
The “Light-Off ” procedure may include the following:
Starting Up
This section provides many items that can be used in a checklist
format before starting up a new or restarting an inservice boiler
and that also act as good reminders. Placing the information in
checklist form simplifies its use and ensures that important steps
are not missed. Relevant information to put into checklist form
should include verifying the following:
(1) that instrumentation and protective devices are operable;
(2) at least one recently calibrated steam pressure gage is properly mounted;
(3) that valves are in good working condition and in the correct
open or closed position;
(4) that gage glasses are illuminated (if required) and functioning properly;
(5) that pressure relief valves are free to operate and expand;
(6) that the main steam-stop valve stem will not be damaged by
thermal expansion stresses;
(7) that fans and boiler feed pumps are ready for service; and
(8) that the chemical injection system is operable.
In installations heavily reliant on computerized controls, boiler
operators still must provide at least one operable gage glass. Note
that ASME Section I, PG-60.1: “Water Level Indicators,” states
the following: “When both remote level indicators are in reliable
operation, the remaining gage glass may be shut off, but shall be
maintained in serviceable condition” [2]. The use of the gage glass
is especially important during start-up when verifying the water
level at the gage glass instead of monitoring the remote level
indicators provides more initially reliable indication of water level.
(1)
(2)
(3)
(4)
(5)
(6)
drum vent opened;
economizer drains closed;
superheater and main steam line drains opened;
header vents opened;
the boiler feedwater line is filled; and
safe, observable minimum water level is maintained.
(1) Light off and operate the specified burners that produce the
most uniform gas temperature distribution leaving the furnace (furnace exit gas temperature, or FEGT). In many cases,
the specified burner may be the lower-middle burner of a
single-wall burner boiler.
(2) Maintain the water level within safe limits by feeding or
blowing down while the pressure is raised.
(3) Maintain the rate-of-pressure increase to keep within the
thick-metal-temperature–specified gradients and the maximum metal temperatures for superheater elements.
(4) Close the drum vents when the steam pressure reaches
25 psig (172 kPa). Nondrainable superheater vents shall be
left opened to permit condensation to boil out.
(5) Check the free expansion of the boiler.
(6) Test the water column and gage glasses by operating the
drain valve.
(7) Test the safety valve by using a lift-assist device.
The reader is also reminded in this section that the curing (or drying
out) of new refractory is performed during the start-up period. If
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 2-13
proper curing and firing process is not followed, the new refractory
may spall or crack due to moisture in the refractory turning to steam
and expanding in the refractory. It is wise to follow the refractory
manufacturer’s instructions. This will minimize refractory damage,
and consequently, boiler hot spots during operation. This curing
period may take from 48hr. to 1wk. to complete.
2.4.5
On-Line Operation
This section reminds the on-line operator which conditions
need to be monitored for the safe, reliable operation of a power
boiler. Boiler operating procedures, if not already in existence, can
be adapted and developed further from this section. In addition,
modifications can be made to fit the boiler operator’s experiences.
Maintenance, examination, and engineering groups may use this
section to verify that a boiler is operating properly, for the basic
information provided in this section can be applied to any boiler
operation. A separate checklist may be assembled starting with the
waterside operation.
2.4.5.1 Waterside Operation Although feedwater treatment is
very important, its title is misleading. Feedwater is about half of
the water cycle; the other half is obviously boiler water. However,
it is agreed that a competent feedwater and boiler-water chemist
or engineer should prepare instructions for feedwater and boiler
water treatment. If the boiler operator cannot justify having a
water chemist on his or her staff, then he or she must provide in
addition to the necessary chemicals all pertinent water chemistry
instructions, training, and monitoring by means of companies
specializing in this type of service. This subject is discussed
further in Article 200 “Protecting Heat Transfer Surfaces.”
Undesirable operating conditions are also reviewed in this
section, among which are the following:
(1) oil in the boiler water;
(2) low water level; and
(3) high water level.
In addition to informing the reader who knows that the fuel
should be shut off under extreme conditions, this section provides
other helpful information. When faced with the water level not
being visible in the gage glass, one is recommended as a first step
to blow down the water column or gage glass to determine whether
the level is above or below the visible range. However, if a waterlevel indicator and a level recorder are available for comparison—
and if the levels are in agreement—blowing down may not be
necessary. As a second step, one is recommended to shut off the
fuel and air while continuing to feed the water. Guidelines are
presented for the high-water-level emergency.
Under the aforementioned—and other—emergency conditions,
the question may arise if the operating personnel are satisfactorily
equipped and trained to react immediately and properly. The
boiler operator must ask him- or herself this question constantly;
moreover, he or she must have a program that ensures a proper
response to emergency conditions. The solution may be regular
training of personnel, a periodic review of procedures, or the use
of readily available checklists.
2.4.5.2 Leaks As stated several times previously, Section VII is
helpful to operating, maintenance, examination, and engineering
personnel. For some persons, it provides new information; for
other (more experienced) persons, it is a useful review. This section
describes the steps to be taken if a serious tube failure in a watertube boiler occurs, among which the following are recommended:
(1) shut off the fuel flow;
(2) shut down the fans;
(3) shut off the feedwater supply.
The question of whether the boiler can continue to remain
in service if small leaks are discovered in waterwall areas is
addressed, to which this section’s response is “yes” if the water
makeup is sufficient. However, other questions not addressed
include the following:
(1) Is the tube leak stream eroding or cutting adjacent tubes or
headers?
(2) Will the tube leak cause starvation and overheating of the
leaking tube downstream of the leak?
(3) Will damage be caused to other components if there is subsequent wet fly ash plugging, causing channeling of gas
flows?
(4) Will there be additional chemicals fed as makeup that can
cause underdeposit-type corrosion?
(5) Is the leak close enough to a burner that if the leak enlarges
it could possibly extinguish the flame?
An experienced engineer should review the considerations in the
foregoing list. When load demands are critical, operators have been
known to operate a boiler with leaking tubes for days. Many of the
foregoing considerations also apply to firetube boilers; however,
it has been noted that occasionally leaking tubes have been fixed
temporarily by applying a steel conical plug at each end of the
leaking tube. This type of fix is considered potentially dangerous,
however, and is discouraged because of the serious injuries that
have occurred from this practice.
Finding larger tube leaks is not a problem for most boiler operators. Indications of leaks normally include the following:
(1)
(2)
(3)
(4)
(5)
high makeup water;
excessive use of water treatment chemicals;
visibility of leaks from observation ports;
water coming from hoppers or from insulation; and
white vapor stack plumes.
Small leaks may continue undetected for a long time.
Before continuing, it is worthwhile to review by way of example
one of the many useful pieces of information provided in this
section and in Section VII as a whole. We review the important
steps that operators should take if a major boilertube failure occurs,
requiring the boiler to be taken off-line immediately. Sometimes,
boilertube failures are significant causes of inservice power boiler
outages resulting in the loss of generation. Boiler operators have
adopted and optimized boilertube-failure reduction programs, but
nevertheless, large boilertube failures cannot be totally avoided.
Large leaks or ruptures can drop pressure and water level very
rapidly, put out the fires, and possibly cause excessive temperatures
in superheaters and reheaters, all of which would necessitate
a boiler’s immediate shutdown. In its review of the boilertube
shutdown procedures recommended for gas and oil burners, this
section specifies that the following minimum steps and precautions
to be taken: shut off the fuel and, after 15–20 min., shut down
the forced draft fans; then shut off all of the steam outlets (main
steam-stop valve and auxiliary steam connections) (it is stressed
that the latter action be taken as quickly as possible to prevent a
sudden drop in pressure from the corresponding sudden drop in
temperature of the boiler water), shut off the feedwater supply to
prevent harmful thermal shock to the thick boiler drums, and adjust
the airflow rate to its permissible minimum to prevent harmful
2-14 t Chapter 2
temperature differentials. These steps can be compared with
existing company procedures, and they may be used to develop
new procedures. Operating personnel should either memorize the
steps or have them readily available.
2.4.6
Out-of-Service Operation
The operation cycle is completed with the shutting down of the
boiler—in this case, a controlled shutdown. An orderly procedure
can be written on the basis of this section. Manufacturer’s
instructions should be consulted to ensure that all details are
covered.
It has been stressed throughout this chapter that comprehensive
operating, maintenance, and examination information is provided
in ASME Section VII. From the information provided in the Outof-Service section, considerations for a controlled shutdown may
include the following activities:
(1) For oil and gas firing, reduce the load to the minimum stable firing rate. Coal firing requires placing igniters in service until the mill runs until empty.
(2) For oil and gas firing, trip the fuel shut-off valves at the
appropriate time. Close all manual valves at the burners
immediately.
(3) As the boiler steam flow drops toward zero, close the main
feedwater control valve and manually regulate the water
level with the bypass valve.
(4) When drum pressure falls to 25 psig (172 kPa), open the
drum vents to prevent the formation of vacuum.
(5) Cool boiler at the controlled rate recommended by the
boiler manufacturer. Do not force-cool the boiler beyond
the recommended rates.
For step (5) in the preceding list, the boiler manufacturer’s
instruction should be followed closely to avoid overstressing and
(consequently) damaging the boiler structure. As a general practice,
thermocouple differential temperatures are monitored as the boiler
is cooled. Some watertube boiler manufacturers recommend
monitoring differential temperature readings between drum-top
centerline and drum-bottom centerline thermocouples, and also
between through-wall thermocouple differential temperature
readings.
Some manufacturers, such as Babcock & Wilcox, may use
a drum wall-thickness of 4 in. (100 mm) as a guideline when
raising the temperature or for cooling curves provided to the boiler
operator [5]. For drum wall-thickness of 4 in. (100 mm) or less,
temperature differentials of 100°F/hr (38°C/hr.) are used for both
top-bottom and through-wall differentials; for drum wall-thickness
greater than 4 in. (100 mm), however, some manufacturers provide
separate heating and cooling curves for the boiler operator to use
when monitoring the two temperature differentials. The expected
practice is for an operator to plot the time-pressure-temperature
differentials as the boiler is cooled. Staying below the chart
differential temperatures will help to ensure that the steam drum is
not overstressed and cracked.
Waterside and fireside cleaning is further discussed in Article
105, “Examination.” However, there are brief recommendations
given in this section that can be helpful reminders. One important
consideration is examining the inside of the steam and mud drums
and the fireside surfaces before any cleaning is done. Many
operationally created conditions can be examined and evaluated
before they are removed and lost during the cleaning process. Before
the inside of the waterside is cleaned and vacuumed, the amount
of deposit and other debris can be seen just after the manholes are
opened and vented; samples can therefore be taken and analyzed.
Any marks along the waterline can be investigated, and any areas
of active corrosion can be seen and evaluated before conditions
are disturbed. Conditions of the water treatment program can be
evaluated with this evidence seen firsthand, enabling samples to
be taken.
In addition, before the boiler wash, the inside of the furnace can
be examined for the amount and type of ash and slag adhering to
the walls. Any flame impingement and clinkers can be examined
and evaluated, and in the superheater areas, the amount and type of
ash and slag can be examined and evaluated. For boilers without
sootblowers in the secondary superheat and reheat tube sections
due to over-designed surface areas, excessive attemperation and
vibration may be created due to ash and slag on and between
tubes. Convection section components can be examined and
evaluated before the evidence is washed away, and soot-blowing
effectiveness can also be evaluated. Many Owner–Operator boiler
examiners, however, prefer the cleaner conditions after the boiler
wash. Conditions before the wash are extremely dirty in addition
to being warmer than desirable. Examinations before and after the
boiler wash necessitate additional time inside the boiler.
The Article “Boiler Operation” is completed with the storage
of the boiler, of which the most common methods are wet storage
and dry storage. (Storage is covered in more detail in Article 200
“Protecting Heat Transfer Surfaces”; it is briefly mentioned here
because it represents the operating cycle’s end.) Today, with
newer, more efficient units (e.g., the combined-cycle units), older,
less-efficient boiler units are run only when necessary. Although
brief, this section provides many good considerations for boiler
operator personnel. The decision to store wet or dry is dependent
on the expected length of the storage period, as well as the climatic
conditions.
If the boiler unit is needed for emergencies, or if short-term
storage is planned, the boiler will be stored wet. This section—
and most water chemistry experts—recommend wet storage with
a nitrogen or steam blanket; for example, after filling the boiler
with treated water a low pressure (5 psig) (35 kPa) nitrogen cap is
applied. Nonetheless, some boiler operators may neglect to apply
and maintain this nitrogen cap; others, knowing that storage will
become necessary, do make provisions for the nitrogen cap. As
years pass, however, operating personnel may change and the
reasons why the nitrogen cap is needed may be lost or forgotten.
Thus the nitrogen cap connections and valves may become static
for years.
The reason for the use of nitrogen for a blanket is traceable
to basic water chemistry. Oxygen in the boiler water is a factor
that causes corrosion. With the oxygen in water, the iron tends to
relinquish its electrons and the iron ion goes into solution. The
nitrogen cap works in two ways: First, the oxygen in water (at a
higher concentration here than in the nitrogen cap) tends to leave
the water until equilibrium is reached; and second, if the boiler is
filled as full as possible with a suitable concentration of an oxygen
scavenger, the nitrogen cap provides overpressure to prevent any
infiltration of air or oxygen.
As mentioned in the section for dry storage, the boiler must be
completely dry. A desiccant should be placed in the drums, and
the boiler should be tightly sealed. For smaller boilers, a 5 psig
(35 kPa) nitrogen cap is recommended for the similar reasons as
for wet storage.
HRSG manufacturers and erectors have used vapor phase
corrosion inhibitors during the layup period after the HRSG leaves
the shop and before it is started up. These proprietary chemicals are
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 2-15
not new discoveries, having been used several years for protecting
internal surfaces after shop hydrostatic testing while the equipment
waits for startup while a plant is erected.
Many articles exist that describe wet and dry storage requirements
and procedures. A knowledgeable water treatment consultant can
provide references. For EPRI members, there are publications that
pertain to boiler storage [6]. The American Boiler Manufacturers’
Association (ABMA) is another source of information on water
treatment requirements.
2.5
BOILER AUXILIARIES—Article 102
This Article covers several important boiler auxiliaries including
burner equipment, air heaters, boiler feed pumps, auxiliary drives,
draft fans, and dampers. One may wonder why feedwater heaters
are not included for discussion, for they preheat the boiler feedwater for better efficiency and also preheat the feedwater to
minimize economizer thermal shock.
Future editions of Section VII can be made more comprehensive
by including feedwater heaters, and with more pictures or illustrations
of the auxiliaries for better descriptions. However, pictures should
not be like the ones of FIG. 102.5-2, Typical Single Stage Turbine
Drive (See Fig. 2.8 for example of lack of parts description.) or FIG.
102.7-1 Typical Outlet Fan Dampers (Multilouver). These pictures
do not even attempt to call out the parts of the component shown.
They merely appear as if they were included to fill in space.
Nonetheless, this subsection offers useful information about
boiler auxiliaries. As is the case for the boiler, the reader is reminded
that detailed operating instructions for these boiler auxiliaries
should be developed following the manufacturer’s instructions.
In particular, procedures for start-up, normal and emergency
condition operations, and shutdown should be developed for each
boiler auxiliary. In addition to procedures, checklists should be
developed for safe, reliable operation.
Throughout this subsection, as each auxiliary is presented, the
reader reviews the following information:
(1) preparing the auxiliary equipment for operation;
(2) placing the auxiliary equipment into service;
(3) normal operating conditions;
and in some cases;
(4) emergency operation
In essence, before a new boiler unit is started, the boiler operator
should be familiar with each piece of auxiliary equipment to be
used. Regardless of whether the equipment is existing or new, the
appropriate personnel should ensure it is installed properly and will
operate as intended.
2.5.1
Fuel-Burning Equipment
The section covers gas- and oil-burning systems in detail.
Regardless of whether a boiler operator has one, two, or all
three types of burning systems, for this critical equipment where
explosions are always a possibility it is obvious (as specified in
the section “Preparation for Operation”) that detailed procedures
covering the step-by-step operation of each burner system should
be developed by the boiler operator personnel. In addition, as
specified continuously throughout Section VII, the manufacturer’s
recommendations should be included and followed in these
procedures. Some common steps and important precautions for all
systems are reviewed before each system is covered in more detail,
examples of which are the following:
(1) Purge the furnace before any igniter or burner is lit—
including purging whenever flames are lost and before relighting. Follow the written company’s and/or manufacturer’s procedures precisely. The use of a checklist is highly
recommended.
(2) Never operate burners at a rate below the safe minimum
level at which a stable flame can be maintained.
(3) The rate of firing during start-up must be controlled to not
exceed the specified or recommended drum-metal temperature differentials and to not exceed superheater-metal design temperature limits.
To enhance Section VII, a useful example can be added to
section 102.2.5 Oil Systems, to show the consequences when the
precaution “Oil spray should not be permitted to strike burner
throats” is not taken seriously. Fires and damages occurred when an
FIG. 2.8 EXAMPLE OF LACK OF PARTS DESCRIPTION (Source: Fig 102.5-2 Section VII of the 2015 ASME B&PV Code)
2-16 t Chapter 2
oil gun assembly was not positioned properly or was retracted too
far from the refractory throat during operation. The result was fuel
oil spraying onto the refractory throat creating clinkers that formed
a barrier for the ignited fuel oil to rebound into the air register and
windbox burning and damaging burner components and windbox
casing. This obviously caused a forced outage of considerable
duration, but could have had a more serious consequence.
The readers should review the burner-type section applicable
to the systems in their plants and should also review their own
company procedures regularly. Section VII covers many basic
reminders that the boiler operator should review periodically for
safe, reliable boiler operation. Answers to questions should not be
left unanswered; one should refer to manufacturer’s instructions or
other resources.
2.5.2
Air Heaters
This section presents an informative review of air heater
operations. The review is applicable to both regenerative (See
Fig. 2.9 Regeneration Air Preheater) and tubular air heaters
(See Fig. 2.10 Tubular Air Heater Drawing). These step-by-step
procedures—beginning with preparing the auxiliary equipment
for operation, followed with placing the auxiliary equipment in
service, and ending with normal operating conditions—can be
used to develop the boiler operator’s own procedures. From this
section checklists can also be developed.
This section alerts the reader to the possibility of fires in the
air heater, of which the cause is primarily the accumulation of
combustibles in or around the air heaters. The review reminds
the reader that temperature-indicating instrumentation should be
installed at the inlets and outlets of both air and flue-gas paths
through the air heater. Doing so can warn of plugging conditions or
the presence of a fire. Checking that burner equipment is operating
properly can minimize the accumulation of combustibles, and
plugging may be minimized by proper soot blowing and off-line
water washing.
The reader is also reminded that units operating at low loads may
develop such problems as the accumulation of unburned combustibles
FIG. 2.9
and the corrosion of the cold end or of flue-gas outlet area. Units that
must operate at low loads will not burn the fuels as effectively as they
do when burning at higher rates, and the flue-gas outlet temperatures
may fall below the acid dew-point temperature. More frequent soot
blowing is necessary when the units operate at low loads. If off-line
water washing is performed, the procedures should be followed
closely and the air heater should be dried thoroughly before it is
placed back in service; otherwise the ash, soot, and other unburned
combustibles will immediately adhere to the damp air heater surfaces.
Some owners include an acid neutralization system in their washes
to help minimize acidic corrosion after the wash should there be
difficulties drying the air heater surfaces. The wash water is made
more alkaline to help neutralize the acidic condition caused by the
wash water mixing with the ash forming a low pH residue.
It should be noted that the FIG. 102.3.1-1 Tubular Air Heater
Drawing of Section VII was revised in the 2004 Edition (See
Fig. 2.10) to show how the flue gas passes through the tubular air
heater.
2.5.3
Boiler Feed Pumps
This section provides guidance in preparing boiler feed pumps
for service, placing them in service and operation under normal
conditions. Also mentioned are washing out of rust-preventing
compounds prior to the initial startup of a new pump and inserting a
‘start-up’ strainer at or before the pump suction for initial operation
and removing it after the water system is clean.
Placing the pump in service requires venting the pump casing,
suction and discharge piping, checking the oil level for pump
bearings and draining inlet water through the pump to bring the
pump case to the same temperature as the inlet water.
During operation, the recirculation system needs to maintain
more than manufacturer’s recommended minimum flow rate
through the pump at all times it is running to prevent overheating,
bowing of the shaft, flashing and ultimate pump seizure. Alignment
of the pump and driver should be verified initially and checked
periodically to protect bearings, shaft mechanical seals as well as
the pump and driver.
REGENERATION AIR PREHEATER (Source: Fig. 102.3.1-3 Section VII of the 2015 ASME B&PV Code)
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 2-17
2.6
APPURTENANCES—ARTICLE 203
Safety valves (now referred to as pressure relief vales in Section
I), water columns, gage glasses, pressure gages, feedwater regulator
valves, and soot blowers are important boiler appurtenances.
Appurtenances are those devices attached to the boiler and, typically,
are addressed in Section I, Power Boilers. This Article provides
new, practical information for some boiler operator personnel, and
serves as a review to more experienced personnel. The amount of
coverage given to each appurtenance appears logical in the context
of its importance for safe, reliable operation.
2.6.1
FIG. 2.10 TUBULAR AIR HEATER DRAWING (Source:
Fig. 102.3.1-1 Section VII of the 2015 ASME B&PV Code)
2.5.4
Auxiliary Drives, Fans and Dampers
The large rotating auxiliaries, that is, boiler feed pumps and fans,
employ either motors or steam turbines as primary drives. They
may be operated at constant speed with control valves or dampers
or with variable speed to vary the output. Startup and monitoring of
drives are the same as with any other motor or steam turbine drive
within the installation.
Forced draft (FD) and, if furnished, induced draft (ID) fan startup,
normal and emergency operation is briefly discussed. These fans
are started with the discharge dampers closed to minimize the
starting load on the driver.
A description of the controls necessary to prevent implosions
when ID fans are used is presented in section 201.7 Furnace
Implosions of Section VII (2.11.4 in this Chapter).
Boiler Pressure Relief Valves
The first section of this Article states the following: “The
pressure relief valves are key devices used to protect against
overpressure conditions.” In fact, the pressure relief valve
is the last line of defense in protecting against a catastrophic
failure of the pressure vessel itself. The pressure relief valve
has such importance in safe, reliable boiler operation that the
NBBI conducts a repair program to certify qualified pressure
relief valve repair organizations under its VR Symbol Stamp
accreditation program. Many U.S. jurisdictions mandate the use
of the NBIC [4] and require that repair of ASME V-stamped and
NB-stamped pressure relief valves be performed by an NBBI
VR-Certificate Holder.
Much of the following information is from experiences with this
program, and should not be considered as official interpretations
of any code. Codes may be revised and readers should consult the
latest code edition and addenda for current information.
Besides providing the rules for certifying the pressure relief
valve repair organization, the NBIC [4] provides guidelines
and recommendations for the testing, inspection, and repair of
pressure relief valves. This section on pressure relief valves covers
similar material as that covered by the NBIC [4]. The NBBI VR
Symbol Stamp accreditation program has not been adopted by
all jurisdictions. For more information regarding this program,
the reader can refer to the NBIC or ANSI/NB-23 [4] (ANSI is an
acronym meaning the American National Standards Institute), or
can visit the NBBI Web site: www.nationalboard.org.
The reader should note that this section pertains mainly to
pressure relief valves that have been in service operating on the
boiler. Obviously these pressure relief valves should be examined
and tested at regular intervals; however, no set code-determined
required time period exists for this examination and testing.
This section recommends that the frequency be determined by a
valve’s maintenance history; it implies that if there is any doubt
one should use 1 yr. as the starting frequency of examination,
testing, and possibly repair. The annual activity should include
the following:
(1) a thorough visual examination;
(2) testing, preferably on the boiler at its operating condition; and
(3) repair, if necessary.
Stated another way, if the examination and testing reveal that
the pressure relief valve will operate properly, and if it was not
damaged during that testing, the pressure relief valve in its current
condition can be returned to service and the next examination and
testing can be scheduled for the subsequent set period.
2.6.1.1 Boiler Pressure Relief Valve Maintenance The reader
should be aware that the VR Symbol Stamp accreditation program
follows the requirements of ASME Section I, Power Boilers [2]
2-18 t Chapter 2
for new pressure relief valves. Much of the information provided
in this section is similar to the maintenance information provided
in the NBIC [4]. The points listed in sections 103.1.2 and in 103.2
should all be included in a pressure relief valve maintenance
program, and are in the main easy to understand; however, certain
items will benefit from further clarification. Section VII FIG.
103.1.2.9-1 Typical Direct Spring-Loaded Safety Valve (given
here as Fig. 2.11) shows the components of a typical pressure
relief valve. In section 103.1.2.3, it is mentioned that the most
reliable way to test a pressure relief valve is on the boiler at
operating conditions. However, this method is not recommended
for pressure relief valves set to open above 600 psig (4 MPa)—
obviously for safety reasons. Testing of pressure relief valves on
the boiler during operation requires one to closely approach the
boiler to hear the pop and the reseating of the disk, and also to
witness the amount of lift of the valve stem. A remote lift indicator
device can be rigged, but doing so is not always possible because
of repair organization limitations.
In section 103.1.2.5, a repair nameplate of the qualified
repair organization is required after the pressure relief valve is
disassembled and repaired. This qualified repair organization
may be a VR-Certificate Holder or one that has received a special
permission from a jurisdiction. If the set pressure is changed, the
corresponding new capacity must be shown on the repair nameplate.
It is specified in 103.1.2.5 that the new capacity be based on that
for which the valve was originally certified. Typically, the NBBI
publication Pressure Relief Device Certifications (also called NB18) can be consulted to determine the new capacity [7]. It contains
formulas and tables for that task. It should also be noted that if
the operating pressure of the boiler is derated by modification (or
for any other reason), the pressure relief valves must be resized to
pass the required capacity at the lower pressure. The newly sized
Cap
Release nut
Top lever
Compression screw nut
Yoke
Compression screw
Spring washer
Drop lever
Spring
Spindle
Top plate
Cover plate
Lift stop
Spring washer
Overlap collar
Guide
Disk holder
Disk collar
Disk
Upper adjusting ring
Upper adjusting ring pin
Lower adjusting ring pin
Lower adjusting ring
Base
Seat bushing
Inlet neck
FIG. 2.11 TYPICAL DIRECT SPRING-LOADED SAFETY VALVE (Source: Fig. 103.1.2.9-1 Section VII of the 2015 ASME B&PV Code)
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 2-19
valves will generally be larger than their predecessors; in some
circumstances, they may actually require the valve openings in the
boiler to be enlarged.
In section 103.1.2.9, checklist items are provided for visual
examination whenever a pressure relief valve is to be tested on
the boiler. One of the recommendations is to gag the safety valve
before any close visual examination – obviously to ensure the
safety of the examining personnel.
2.6.1.2 Boiler Pressure Relief Valve Testing This section
103.1.3, states the following: “After visual examination and
successful hand lift operation, each valve should be tested for the
following operating characteristics.” This statement is not totally
correct; if the valve were tested for the three pressure relief valve
operating characteristics—the opening pressure or set pressure,
the closing pressure or blowdown, and the capacity—a hand lift
test would not need to be performed. The information provided
in this section is very useful for the pressure relief valve repair
personnel and for the engineer in charge of the repair program.
However, when the NBBI VR Symbol Stamp requirements are
followed, testing is performed only to demonstrate the set pressure
and response to blowdown, as well as the seat tightness, which
would apply to an inservice pressure relief valve after it has been
repaired. The capacity or measurement of the spindle lift is crucial
when a repair organization is required to demonstrate the pressurerelief valve repair capability.
The opening or set pressure for any pressure relief valve must be
within the permissible variation specified in ASME Section I, PG72.2 [2]. For closing pressure (or blowdown), Section I, PG-72.1
requires that the valve not chatter and that minimum blowdown
should not exceed 2% of the set pressure or 2 psi, whichever is
greater. It should be noted that as of the 1998 edition of Section
I, PG-72.1 [2] was revised to expand the maximum blowdown
requirements to 4% of set pressure for spring-loaded pressure relief
valves. However, with the first addendum after the 2004 edition
blowdown values were omitted from nameplate stamping and inservice blowdown requirement were eliminated. For capacity, the
measurement of the spindle travel or lift is useful for determining
if the rated capacity can be achieved without actually measuring
the flow rate. Both the original valve nameplate and the NB-18
publication [7] give one the lift data necessary for determining the
rated capacity, but one is also reminded that the lift measurement is
meaningful only if the valve-adjusting rings are correctly adjusted.
As noted in this section, pressure relief valve testing is normally
performed when the boiler is being shut down for examination
or for a planned overhaul. If the pressure relief valve is damaged
during pre-shutdown testing it can be repaired during the outage. As
would be expected, for this testing the boiler operator should have
a written procedure, which should be reviewed before the testing
begins. If pressure relief valve gagging is necessary, the seal at the
spindle adjustment must be cut. Under most repair programs, the
testing must be performed by, or under the supervision of, qualified
pressure-relief valve repair personnel. If the pressure relief valve
passes the visual examination and tests, it can be returned to service
in its current condition. If a seal was cut off, that seal must then be
replaced. Under most repair programs, only qualified safety valve
repair personnel can replace the seal.
Lift-assist devices may be used to set and check the set
pressure of certain pressure relief valves. The pressure relief valve
manufacturers provide these devices for certain models in their
product line. As mentioned in this section, lift-assist device testing
cannot verify valve performance; only full-pressure popping can
provide the valve performance data. However, lift-assist device
testing is permitted by the NBIC [4] and ASME Section I for
conditions in which full-pressure popping testing is not practical,
such as for high-pressure and capacity pressure relief valves welded
to the boiler and wherever full- pressure popping testing will almost
certainly damage the seating surfaces. For such exceptions, the
repair organizations must meet additional requirements to ensure
that the repaired pressure relief valve will operate as intended.
These additional requirements include calibration of the lift-assist
device by an authorized organization on an established frequency
(normally annual) and by developing and following exact testing
procedures.
Pressure relief valve body drain and the discharge pipe drain
should always remain open. Two obvious problems may result if
water is allowed to collect in the discharge area of the pressure
relief valve: First, water left around the seat disk area can eventually
cause particle buildup at the seating surfaces, eventually affecting
set pressure popping; and second, water that is unable to drain away
can create backpressure that may affect the valve performance.
Water not drained from the drip pan may be dangerous to passing
personnel should the pressure relief valve pop. Using FIG.
103.1.2.9-2 Recommended Direct Spring-Loaded Safety Valve
Installation (included as Fig. 2.12 Safety Valve Installation) the
bottom of the discharge piping should be positioned well below
the top of the drip pan. Especially if the discharge piping has
bends that could increase the amount of blowback should the valve
pop. The side of the drip pan will minimize the sideways spray to
personnel nearby.
Before performing a boiler hydrostatic pressure test in which the
test pressure is near or exceeds the set pressures, the pressure relief
valve may be removed if it is flanged; or alternatively, gagged,
or a hydrostatic plug may be installed, installing a gag certainly
being the simplest. (However, one is reminded to not tighten
the gag screw excessively to avoid damage to the spindle and/
or seat.) Hydrostatic plugs take more effort to install. For many
pressure relief valve models, hydrostatic plugs are required by the
manufacturer during shipment to prevent damage to the seating
surfaces. If that is the case, the manufacturer not uncommonly
insists that his or her factory representative be at the installation
site to supervise the hydrostatic plug removal before the safety
valve can be put into service; otherwise, any warranty is voided. In
hydrostatic testing, the hydrostatic plug is placed between the nozzle
seat and disk, where it protects the seating surfaces while adding
space between the nozzle and disk to increase the compression of
the spring, thereby allowing up to 1.5 times maximum allowable
working pressure (MAWP) for this type of testing.
Another useful piece of information provided in this section is
that during boiler hydrostatic testing, a slight amount of leakage
may be expected across the seats because the seats are designed for
steam service, not for cold water.
2.6.2
Pressure Relief Valves for Economizers
and Auxiliaries
In addition to the pressure relief valves on the steam supply
system that protect against overpressure conditions, direct springloaded pressure relief valves (safety relief valves and relief valves)
and pilot-operated pressure relief valves are frequently used on
economizers and on the auxiliary systems such as heaters, condensate
returns, boiler feed-pump turbines, evaporators, compressors, and
pressurized tanks.
This section includes the ASME Section VIII-jurisdiction
pressure relief valves. Pressure relief valves can be used for
2-20 t Chapter 2
Anchor discharge piping
solidly to building structure
Radial clearance required
when valve is operating
Bore equal to
nominal valve
outlet size
Vertical clearance required
when valve is operating
Drain
Body drain
Flanged inlet shown
welded inlet similar
Drain
Bore equal to nominal
size pipe of valve inlet
Short as possible
[24 in. (600 mm) max.]
FIG. 2.12 RECOMMENDED DIRECT SPRING-LOADED SAFETY VALVE INSTALLATION (Source: Fig. 103.1.2.9-2 Section VII
of the 2015 ASME B&PV Code)
steam, air, or gas; in other words, for compressible fluids and
for liquid service. Relief valves are limited to liquid service and
to noncompressible fluids. It is interesting to note that because
pressure relief valves are suitable for nearly all services, relief can
be by full-popping for steam, air, or gas, and by small releases for
liquid service. Relief valves provide for a gradual release of liquid
that is sufficient to lower the pressure; a full, sometimes violent
pop does not result.
Again, one should remember that the NBBI VR Symbol Stamp
program provides for certification of qualified Section VIII
pressure-relief valve repair organizations. A repair organization
can be qualified for Section VIII pressure-relief valve repairs only,
for Section I safety valve repairs only, or for both. The VR Symbol
Stamp repair program ensures that qualified repair personnel
working under an acceptable quality system program do repairs
on Section VIII pressure-relief valves. The NBIC and/or the NBBI
should be consulted for additional information.
2.6.2.1 Examination and Testing In a power plant, Section VIII–
type pressure relief valves are found on such boiler auxiliaries
as feedwater heaters, reboilers, fuel-oil heaters, air tanks, and
certain piping. In some jurisdictions, the NBBI VR Symbol Stamp
repair program includes the pressure relief valves on these ASME
Section VIII feedwater heaters, reboilers, fuel-oil heaters, and air
tanks. Possibly, some Owner–Operators ignore these pressure
relief valves over a period of years, never touching them unless
there was leakage.
The section recommends a periodic examination, testing,
and maintenance program to ensure proper valve function. (The
modifiers “highly” or “extremely” should perhaps precede the word
“recommends” to stress the importance of ensuring that the pressure
relief valves for protected equipment will open at the predetermined
pressure and at the minimum required capacity, and also of ensuring
that the valves are not frozen shut from years of neglect.) This
program should include verification of set pressure, a valve-tightness
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 2-21
test, and a test of valve lift (for steam, air, and gas service). This
program does not require the automatic removal and stripping down
of the valve. It depends on the service fluid, the time elapsed since
the previous repair, and the service experience recorded. A typical
pressure relief valve maintenance procedure includes the following:
(1)
(2)
(3)
(4)
removing the valve from the equipment for the repair shop;
performing a close visual examination;
testing on a test stand; and
disassembling (if necessary).
If the valve passes the visual examination and testing, it most
likely can be returned to the equipment without any further work.
As stated previously, the frequency of this program depends on the
service fluid, the time elapsed since the last repair, and the service
experience gained by the boiler operator. This section, however,
suggests 6 months to no more than 2 years. Some Owner–Operators
may be influenced by unit overhaul periods; if they are on a 2 yr.
overhaul cycle, these Section VIII pressure relief valves will be
examined and tested every 2 yr. If overhaul frequency is to be
influenced by operating and maintenance experience, it is important
to establish a history for each valve. One way to accomplish this
task is with repair checklists that also serve as written histories
for the valves. The repair checklist records all relevant data on
each pressure relief valve in addition to ensuring that the proper
examination, testing, and repair steps are completed.
Whenever a replacement valve is procured, or whenever the
set pressure is changed or conversions are made to the valve,
the proper capacity must be assigned or confirmed. Unlike the
provision for ASME Section I [2], the provision for ASME Section
VIII [8] does not provide criteria for assigning valve capacity to
a pressure vessel—a task that is left to the boiler operator instead.
For feedwater heaters, most boiler operators follow the Heat
Exchange Institute (HEI) criteria [9] for the shellside- and the
tubeside-pressure relief valves capacities. The tubeside sees boiler
feedwater or condensate. The pressure relief valve protects the
tubeside should the inlet and outlet isolation valves be closed and
the pressure increases from the effect of the shellside heat. Because
feedwater and condensate are noncompressible, the tubeside
pressure relief valve needs only to release a small quantity of fluid
to reduce the pressure.
The shellside of the feedwater heater normally sees low-pressure
extraction steam; however, shellside pressure relief is based on a
tube rupturing in two places within the shell, causing over-pressure
when isolation valves are in closed position. The relief valve is
intended to relieve the feedwater pressure (a noncompressible
fluid) rather than steam. The reader should refer to the HEI
document [9] for further information.
The sizing or capacity of air tank pressure relief or air receiver
tank pressure relief valves is sometimes based on it being at
least two times the air compressor–rated capacity. Again, one is
reminded that the Owner–Operator is given the responsibility of
determining the required capacity.
This section briefly addresses valve tightness tests. (Again, the
reader should remember that such tests are for Section VIII–type
pressure relief valves; the tests do not apply to ASME Section I–
type valves.) There are three tightness tests: the bubble test (API
Std. 527) [10], the wet paper towel test, and the cold rod test.
In the section “Lift and Blowdown,” to measure the valve stem
lift while the pressure-relief valve is tested on a test stand under
shop conditions reveals whether the full-relieving capacity can be
reached. The rated lift can be found in the NB-18 publication (or red
book) [7] in addition to the manufacturer’s data. One is reminded
that blowdown characteristics are only meaningful for steam, air,
and gas service, in which case at set pressure the valve fully pops or
lifts to reach as high a capacity discharge as possible. (Blowdown
is the difference between the set pressure and the closing pressure.)
For Section VIII-type valves [8], the preferred blowdown should
not exceed 7% of the set pressure or 3 psi, whichever is greater.
Blowdown does not pertain to liquid service in which very little
discharge is necessary for noncompressible fluids to relieve the
pressure to an acceptable level.
Finally, it is stressed that when repairs are made the manufacturer’s instructions must be followed precisely, and the
qualified pressure relief valve repair personnel should work with
the latest manufacturer’s repair manual. Each step in the manual
should be followed; if any questions or discrepancies arise, the
manufacturer’s service or technical group should be contacted
and its instructions followed. In addition, all critical parts should
be procured from the valve manufacturer or its authorized agent.
(Critical parts are the parts of the pressure-relief valve that affect
flow and valve performance.)
2.6.2.2 Pressure Relief Valve Testing This section of this
Guide describes requirements for non-Section I pressure relief
valves very similar to those of the NBBI VR Symbol Stamp repair
program. Certainly, pressure relief valves should be tested after
being repaired to ensure that the valves will function properly.
There are various methods used for testing. Inexperienced,
uninformed organizations may use the simple hydraulic hand pump
for all testing for steam, air, gas, or water service, whereas others
use a nitrogen gas source connected directly to the underside of the
valve to be tested. Such organizations eventually learn that these
are not appropriate methods because testing should be performed
with the same or similar test media, and suitable capacity should
be provided to test the functions of the valve.
The more informed repair organization may add sophistication
to its testing program by constructing a J-watertube test stand
device for liquid service valves or a nitrogen gas test stand device
for steam, air, and gas service valves. These devices are an
improvement from the first methods, because the available capacity
for testing has increased, similar testing media are used, and the
strength or thickness of each design will determine the maximum
set pressure test. However, for the nitrogen gas test stand device,
the capacity is often insufficient because of the sizes usually built,
the source capacity, and the hazards involved when testing is
done with a compressible fluid. If steam service valves are tested,
it is recommended that the test stand have heating provisions to
replicate the inservice temperature of the valve.
More sophisticated repair organizations build or procure larger
test systems with larger volume test vessels and accumulator
vessels, digital pressure gages, larger pressure sources, and using
the proper test medium. They verify the quality of workmanship
for all functions (including lift and blowdown) depending on the
capacity of the test system and the size of valve tested.
Organized repair programs, such as the NBBI VR Symbol Stamp
program, require that the pressure relief valve repair personnel
pass the repair organization’s pressure relief valve training
program before being allowed to perform repairs. Only qualified
pressure relief valve repair personnel should be allowed to perform
the repairs under the repair organization’s formal program.
Once qualified, the pressure relief valve repair personnel should
be reviewed annually to ensure that proficiency is maintained.
Repair includes valve examination, repair, and testing. Testing
includes installing and removing test gags or hydrostatic plugs and
2-22 t Chapter 2
witnessing and recording test data on checklists in addition to any
testing on the test stand.
2.6.3
Water Columns, Gage Glasses and Level
Transmitters
All boilers having a fixed water level are required to have at least
one gage glass installed and operational (Section I, PG-60). Boilers
with maximum allowable working pressure above 400 psi (3 MPa)
are required to have two independent water-level indicators, with
at least one being a gage glass. There are no alternate devices to
a gage glass that are allowed to replace the specified “transparent
device that permits visual determination of the water level.” See
Fig. 2.13 (Section I, Figure PG-60.3.9).
A water column is a vertical pipe connected to the steam drum
water space below the lowest permissible water level and to the
steam space above the highest permissible water level. A water
column is considered an extension of the boiler water/steam spaces,
and isolation valves between the water column and the drum are not
required, but are optional per Section I, PG-60. If furnished, such
valves must be locked or sealed open except on some automatically
fired boilers operating below 250 PSIG (1.7 MPa).
If the inservice gage glass is not readily visible from the normal
workstation of the operator who controls the feedwater supply,
the operator must have two independent remote level indicators
continuously available and readily viewable at the normal
workstation.
Gage glasses and water columns are required to be blown down
to prevent sludge from interfering with their proper operation.
Improper blowdown can result in sludge accumulating and
inaccurate boiler status being available to the operator. Section
VII, Figure 103.4.1-1 (in this Guide, Fig. 2.14) shows and explains
proper gage glass and water column blowdown.
2.6.4
Pressure Gages
Pressure gages are key to the safe, reliable operation of boilers.
These gages should be removed, examined, and calibrated on a
routine basis, the normal cycle of which may be once every 12 mo.
This section 103.6, provides information on the selection and
care of pressure gages with which all operating personnel should
become familiar.
Some operators lack a schedule for tending to their pressure
gages. One not very good reason for not having a pressure gage
maintenance program is that it is too time-consuming. Also, the
pressure gage conditions may be verified by comparing two or
more pressure gages on the same system. One reason for the
comparison method is that operating pressures are normally less
than the design or maximum allowable working pressure; thus a
certain amount of plus-or-minus variation is reasonable. However,
industrial boilers do sometimes operate close to the design
pressure.
Many Owner–Operators may be required by various repair
programs (e.g., the NBBI’s R- and VR-programs) to calibrate test
pressure gages within a certain time period of performing a test. This
is a quality control program requirement that encourages following
the proper procedure. For the normal operation of equipment,
however, some Owner–Operators believe that the comparison
method may be sufficient if several pressure gages are installed,
such as on large boilers. If only one pressure gage is installed, as
is the case with many ASME Section VIII–type pressure vessels
as well as smaller industrial boilers, the comparison method
obviously cannot be performed. Thus a scheduled examination and
recalibration definitely should be in existence.
In an instrumentation recalibration program in which deadweight-testing devices are used to calibrate pressure gages, one
should not forget that these devices should be calibrated as well.
Deadweight testers appear simple and durable; nevertheless,
weights and other parts of the devices may deteriorate over time.
Depending on the environment in which they are used and stored,
the calibration period may range from 3–5 yr. The calibration
system used should be traceable to the National Institute of
Standards and Technology (NIST).
2.6.5
Steam
Steam
B
Glass
A
A
B
C
Water
D
A — Not lower
than B
C — Not higher
than D
C
D
Water
FIG. 2.13 TYPICAL INSTALLATION OF A BOILER WATERLEVEL GAGE (Source: Fig. 103.4-1 Section VII of the 2015
ASME B&PV Code)
Feedwater Regulators
Depending on the boiler type, size, and intended service, the
feedwater regulator (i.e. feedwater control valve) may be operated
by single-, two-, or three-element control. Single-element control
is usually based on level only. Two-element control is based on
level and steam flow, and three-element control is based on level,
steam flow, and feedwater flow. In any case, a feedwater regulator
is strongly recommended for all boilers.
A feedwater regulating valve should have design features to
allow emergency manual operation. It should be provided with
a full-capacity manual bypass. These bypass valves should be
at locations that permit observation of the water level. Unless
the operator can see the steam drum gage glass whenever it is
necessary to operate the feedwater flow manually, an assistant
should be stationed to watch the gage and signal the operator.
During each periodic boiler examination, the condition of the
boiler feedwater piping and the feedwater control valve should be
determined. Typical conditions to look for include
(a) accumulations resulting from the feed of phosphate into the
system upstream of the feedwater regulator. Any deposits
found from this source are predominantly white.
(b) wire drawing of the regulator. This is caused by the valve
operating in the nearly closed position. Thus, the feedwater
regulator rarely opens to its design position and water-level
control is usually erratic.
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 2-23
FIG. 2.14 GAGE GLASS AND WATER COLUMN BLOWDOWN PROCEDURE (Source: Fig. 103.4.1-1 Section VII of the 2015
ASME B&PV Code )
(c) erosion or corrosion of the feedwater piping and the regulator valve. This may be caused by feedwater with high or
low pH, high oxygen levels, or both.
2.6.6
Soot Blowers
Boiler performance and reliability are directly related to the
cleanliness of the heat transfer surfaces. Thus, when firing ashbearing fuels such as heavy fuel oil, ash deposits must be controlled
by soot blowing. The medium for soot blowing can be either steam
or compressed air. Blowing pressures are recommended by the
Manufacturer.
On smaller boilers, soot should be blown only when the unit
is operating at a steaming capacity of over 50% with stable
combustion conditions. During soot blowing, the performance of
each blower should be monitored so that abnormal conditions can
be detected. Before a blower employing steam is placed in service,
the piping should be warmed and the moisture drained.
2.6.7
Fusible Plugs
Fusible plugs are seldom used on modern boilers. Fire-actuated
fusible plugs, if used, are located at the lowest permissible water
level as determined by the boiler manufacturer. Steam-actuated
plugs, if used, are so located that they will operate when the water
level is at the point where a fire-actuated fusible plug would be
located.
It is strongly recommended that fusible plugs be renewed at least
once each year. Fusible plug casings that have been used should
not be refilled. Details are covered in Section I, PWT-9.3, A-19
through A-21, and Figure A-10.
2.7
INSTRUMENTATION, CONTROLS,
AND INTERLOCKS—ARTICLE 104
This short Article focuses on an important subject requiring
specialization, expertise, and experience. In this age of rapidly
changing PC technology, control systems are redeveloped
constantly. Instrumentation and controls personnel must stay
abreast of such changes. Not that many years ago, pneumatic-type
instrumentation and analog control systems were still the norm, but
with the advancement in technology came the digital electronics–
type instrumentation and digital control systems. Because the
response to operation has become faster and the hardware has been
found to be more reliable in digital systems, pneumatic systems are
quickly becoming obsolete. Parts for older pneumatic instruments
may therefore be unavailable, so plants will find it necessary to
2-24 t Chapter 2
change with the times to use hardware that is now more readily
available.
There still remain some small, older units in which the control
panel is located on a convenient operating area. Instruments are
visible from the panel where the operator is more interactive with
the equipment and continuously monitors the conditions. In larger
installations, however, central control rooms have become the
norm. In installations that used pneumatic-type instrumentation,
controls, and interlocks, operators spent most of their time
in central control rooms, listening and watching for alarms,
monitoring many circular chart recorders and other indicators, and
making adjustments with knobs and push buttons. By being remote
from the boiler and its auxiliaries, it was necessary for operators to
include as much redundancy as possible for safety reasons.
Modern power plants have all-electronic instrumentation, controls,
and interlocks—all controlled by a computer or microprocessor—
often referred to collectively as the distributed digital control system
(DCS). Response is faster, hardware more reliable, and CRT-based
consoles can display many controls on one or two screens. The display
area of coverage has become smaller, and controlling and adjustment
points are more quickly accessible.
Control engineers have become necessary to program the
systems, using logic to institute various control strategies. In many
plants, the instrumentation and controls maintenance personnel are
called I&C technicians; as with the operators, they must have a
thorough knowledge of the instruments, controls, and interlocks
for the safe, reliable operation of the power boiler.
2.7.1
Indicators and Recorders; Water-Level
Indicator; Controls and Interlocks
These three rather brief sections provide basic information
for less-knowledgeable personnel and provide a good review for
more experienced personnel involved with instruments, controls,
and interlocks. From the basic information presented in these
sections, readers have many publications available to expand their
knowledge on specific subjects. Regarding the section “Checking
and Testing,” boiler operators may become complacent with that
section’s provisions for the maintenance of automatic controls;
they may forgo a regular, complete conditional and operational
check of instruments, controls, and interlocks. These two sections
therefore recommend annual conditional and operational checks to
ensure safe, reliable boiler operation.
Adding pictures or illustrations should enhance and provide
better understanding of the intricate subject of this subsection.
2.8
EXAMINATIONS—ARTICLE 105
This subsection concerns the examination of inservice or operating
power boilers. The particular examinations include the following:
(1) condition assessment
(2) jurisdictional operating permit examinations.
Parts of both can be performed during operation and during an
outage. The information covered in this Article is similar to that
provided in the NBIC for NBBI-Commissioned Inspectors [4].
Section VII recommends two separate examinations: one by the
Owner–Operator Examiner, the other by the Inspector or Jurisdiction
Inspector. (For Code inspections: Authorized Inspectors examine
new construction whereas an Inspector examines inservice boilers.)
These inspections also depend on whether the jurisdiction where the
power boiler operates is an NBBI member, whether it mandates the
NBIC, and whether it has adopted the R Symbol Stamp program
requirements for the repair of boilers and pressure vessels.
To ensure safe, reliable power boiler operation, these inspections
should be independent. Owner–Operator Examiners may have
varying titles: Plant Examiner, Boiler Examiner, boiler engineers,
or boiler maintenance engineers, for example. Whatever their title,
however, this subsection specifies that Owner–Operator Examiners
should be knowledgeable by education and experience with the
construction, examination, operating, and maintenance procedures
for power boilers, and should be specifically designated by plant
managers. Stated another way, Plant Examiners are boiler experts,
their decisions are to be followed. These Plant Examiners should be
as knowledgeable of the ASME Boiler and Pressure Vessel Codes
as the Authorized Inspectors are. Plant Examiners should have
detailed design knowledge of the components used so that during
examinations any nonconformance can be evaluated and decisions
can be made for the proper corrective action. Plant Examiners
should also be knowledgeable of welding and nondestructive
testing (NDT) methods, for repairs usually involve some welding
and examination by these methods. Plant Examiners perform the
condition assessment examination to ensure that the boiler is in
good operating condition and that it will operate safely and reliably.
Inspectors also perform examinations to ensure safe operation in
addition to performing the operating permit examination.
With jurisdictions having mandated the use of the NBIC [4],
some Owner–Operator have received accreditation as part of the
NB Owner/User Inspection Organization (O/U Organization).
One requirement for accreditation is that the O/U Organization
will employ Inspectors with valid NB Owner/User Commissions,
who obviously should have as much knowledge and experience
in examining power boilers as other Inspectors, as well as Plant
Examiners. Inspections may include the inservice inspections for
jurisdictional-operating permit requirements as well as the repair
and alteration inspections. When the Plant Examiner is also the
O/U Commissioned Inspector, the two—condition assessment
examination and operating permit inspection—usually become
one examination. It is believed that this method of examination to
ensure safe, reliable power boiler operation gets better results than
using a third party inspector, for the O/U Commissioned inspector
is typically very familiar with the equipment examined and is
normally made aware immediately of all problems as they are
happening and therefore can (when necessary) respond faster. Bias
should not be an issue with the required NB controls in place. The
O/U Commissioned Inspector has the same fears as the Authorized
Inspector when violations and penalties become issues. One such
fear is the loss of his or her NB Commission.
For newly constructed boilers, when the Owner–Operator does
not have the O/U Organization accreditation, the Plant Examiner
must perform the first examination, preferably by using a checklist
of the items to be examined immediately followed by the use of
discrepancy punchlists. Follow-up to verify completion of the
punchlist is then required; the Authorized Inspector will then
perform the jurisdictional operating permit examination if required.
2.8.1
Examination of Internal Surfaces and Parts
The first paragraph of this section specifies the basic purpose
for the internal examination and what areas should be examined.
Whether it is the Plant Examiner, the O/U Commissioned Inspector,
or the Inspector performing the examination, the physical structure
should be examined to determine its adequacy for service. In any
of the preceding situations, the review of ASME Section I, Fig.
PG-58.3.1(a) titled “Code Jurisdictional Limits for Piping—Drum-
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 2-25
Type Boilers” (See Fig. 2.1) or Fig. PG-58.3.2 titled “Forced Flow
Steam Generators” [2] in order to establish the limits of the power
boiler–operating permit examination.
Obviously, this section pertains to the internal examination
during outages. All listed safety precautions must be taken to protect
persons entering the air side or the water side of the boiler. Most
boiler operators use an entry permit system regardless of whether
a “confined space” is involved. Sign-in and sign-out sheets, which
must be completed, are posted at all manholes. Examination inside
the boilers should be of the “buddy system” type in which the
examiner does not enter the boiler unless he or she is accompanied
by another person standing by outside the manhole. A good safety
reference is provided in the NBIC [4].
Especially when examining large power boilers, it is very important that the Plant Examiner or the O/U Commissioned Inspector
be in good physical condition. As specified in the section’s first
paragraph, the entire boiler shall be examined. There are many
tight, small openings where an examiner, to gain entry, must hang
on to a structural member and pull his or her weight up through the
opening. In addition, there are many dirty, dusty spaces into which
the examiner must crawl on his or her hands and knees. Naturally
the examiner must not fear small, confined spaces.
The details provided in this section, along with checklists and
small, readable drawings, enable the Plant Examiner to perform
a reasonable examination and to be able to record items requiring
immediate attention or consideration. For boiler operators without
their own checklists, the checklists in the Non-Mandatory Appendix
A provide a good starting point. Plant Examiners must know in
advance what they will be examining. In addition, they must be
able to document findings and provide the necessary punchlists to
correct any nonconformances.
For the examination of the steam drum interior, plans should be
made to remove necessary internals to examine the full length of
the steam drum. Some manufacturers have steam drum internals
with designs that make access extremely difficult. Loose, worn, or
missing components will not be seen if the steam drum access is
limited to only the two manhole ends.
When inside the furnace of a watertube boiler, the examiner
should pay particular attention to any signs of burner flame
impingement. Flame impingement, plus a dirty interior waterwall,
may be a first indication of bulges or blisters on the fireside. Later,
these bulges or blisters may cause tube leaks unless the burners are
adjusted properly and the boiler is internally cleaned.
For purposes of clarity in reporting and understanding of
reports, a blister may occur if the overheated tubewall had internal
discontinuities such as laminations or seams. Overheating caused
by flame impingement and internal deposits may cause the tube
material to separate outward at the lamination or seam. A bulge,
on the other hand, occurs through sound tubewalls and occurs
from the through-wall metal overheating that may be caused by
the flame impingement and internal deposits. During operation,
burner flame impingement can be observed through the furnace
view ports. During any overhaul outage, the plant examiner should
verify that the view ports are clear and that repairs are made before
the boiler goes back on line.
The refractory should be examined, especially for tangenttube boilers and wherever it is used for sealing (such as for tube
penetrations). Maintenance personnel do not always realize that
refractory does not last forever; the average lifespan is 10 to 15 years.
depending on the abuse to which it is subjected. Boiler washes
coupled with the sulfur in the flue gas help make the refractory brittle
and crumbly. Vanadium in fuel oils is also known to cause refractory
deterioration. Ensuring that the refractory is replaced at the first signs
of deterioration can reduce hot-spot related forced outages. For the
older watertube boilers, many Owner–Operators find it necessary
to conduct condition assessments beyond the visual examinations,
which can possibly help ensure that an unplanned forced outage
does not occur. By anticipating problems, the boiler operator may
be able to properly plan and budget for the repair or replacement.
Much of this condition assessment involves the monitoring of certain
critical components over time, and it should be noted that many of
the more modern flame safeguard controls used on industrial boilers
have firing-cycle counters and elapsed run-time indicators built
into their annunciation system for this very purpose. Techniques
used for the condition assessment monitoring include magneticparticle examination of welds to detect the onset of fatigue and/
or creep damage cracking; ultrasonic thickness testing to monitor
corrosion and erosion; video probe internal examinations to monitor
corrosion, erosion, fatigue, corrosion-fatigue, and creep damages;
metallography in-situ replications to examine for the onset of creep
damage; and steamside-oxide-scale-thickness measurements to
estimate the remaining useful life in superheater and reheater tubes.
Tube samples are cut and removed from the waterwalls to assist with
the determination for chemical cleaning and for tube failure analyses.
When headers are video-probe-examined, access may be
through the header handhole plugs; however, some utilities avoid
going through these handhole openings for fear of causing damage
to the header over time. Such utilities prefer to put forth more effort
by cutting tubes near each end of the header and installing a pullstring to assist the video-probe camera and insertion tube. Less
damage is created by cutting and re welding small-diameter thin
tubes. In firetube boilers, areas to be examined should include the
water leg at the back of water-cooled reversing chambers and the
upper surfaces of the furnace, both to check for an accumulation of
scale or other insulating deposits. In addition, the tube-to-tubesheet
joints and tubesheet ligaments should be examined for signs of
leakage or cracking. Other areas to be examined should include all
stays and also the welds at the furnace-to-tubesheet joint.
2.8.2
Examination of External Surfaces and Parts
The external examination should take place both as a hot examination during operation and a cold examination during an outage.
As implied in this section, comparisons between hot and cold
conditions are made in addition to other checks. The checklists in
the Non-Mandatory Appendix A also cover external surfaces. To
make examinations more orderly when developing site-specific
checklists, external items should be segregated into those items to
be checked when the boiler is in operation and those to be checked
during an outage.
For piping, hot and cold examinations must be performed by the
Plant Examiner for the main steam line, or for the hot reheat lines
or cold reheat lines if they exist, and it is also recommended that
the boiler feedwater line be both hot and cold examined. These
are all considered high-energy lines because of the high pressures,
or the high temperatures, or both. In case of damage, personnel
are at risk and damage to equipment may require a costly and
long outage period for repairs. Pipe support indicators and scales,
whether constant-support– or variable-support–type spring pipe
hangers, should be recorded and evaluated. The supports should
provide a free-floating piping system to avoid undue stress to the
piping system and connections to the boiler and other equipment.
Excessive vibrations should be evaluated and analyzed to prevent
fatigue-creep damages. Piping stress analysis programs are
available and can be used with the proper training.
2-26 t Chapter 2
For boiler-operating permits, most jurisdictions require that
after 6 months of operation, an external examination be performed
when the boiler is operating. Obviously doing so will show whether
the various components are functioning properly. If the Owner–
Operator is part of an NB O/U Inspection Organization, the O/U
Commissioned Inspector can perform the necessary external
examinations during these 6 month examinations. For external
examinations while the boiler is operating, visual examinations
will include examining the safety valves, gage glasses, and pressure
gages. Also, valves should be examined for signs of leakage through
packing glands and gaskets; any leak has the potential to cause
serious damage if allowed to continue, so it should be corrected at
the earliest possible opportunity.
2.8.3
Care and Maintenance
In addition to covering housekeeping requirements, this section
covers the examination documentation, records, and logs that
typically must be kept—all constituting the history and events
precipitating a problem as well as the conditions that require fixing.
It is desirable to enter all relevant information into a computer
program from which the information can be retrieved quickly and
easily.
Many Owner–Operators have created computerized work
orders, with which planning and scheduling, monitoring, updating,
and reporting are included. The plant examiner may use these
computerized systems to input punchlist items so that such items
will be dealt with immediately, if necessary. Status records, along
with other information, can also be quickly retrieved.
More formal examination reports or records of each examination
by the Plant Examiner may need to be recorded and stored in
separate book format for reporting and archival purposes. These
reports are usually separate from the records assembled from
the work order system, and list the findings, provide evaluation
and analyses, and present recommendations. However, because
computer scanners are now readily available, these reports may be
entirely computerized for storage and easy retrieval.
The Plant Examiner or O/U Commissioned Inspector should
have easy access to all boiler information, especially for repair
instructions. Because most boiler drawings were originally drawn
and issued in large size, the plant examiner may find the reducedsize boiler drawings in the manufacturer’s data books useful,
or he or she may prefer to reduce large drawings into notebook
size. It is stressed that reduced size drawings are easier to file in
a binder for each boiler, can be quickly reproduced in the copier,
and can also be reproduced by a scanner when repair instructions
are communicated. (It is so true that a “picture is worth a thousand
words.”) As-built details can also be recorded on reduced size
sheets for more convenient filing and retrieval.
2.8.4
General Listing of Examinations
A listing of the typical examinations other that the boiler tubes
and drums previously discussed is presented for use in preparing
checklists for operating and outage examinations.
2.9
REPAIRS, ALTERATIONS,
AND MAINTENANCE—ARTICLE 106
2.9.1
Repairs and Alterations
This section was added after the 1980 edition to acknowledge
the wide acceptance of the NBIC by jurisdictional authorities
[4]. This section is surprisingly brief for a subject of marked
importance. However, the NBIC is covered more extensively
in previous sections, to which the reader should refer back for
additional information.
For maintenance personnel who are not too familiar with the
NBIC, it stressed that the NBIC applies to repairs and alterations
of power boilers and pressure vessels that are operating and hence
not of new construction. A more precise explanation is given by
Bernstein and Yoder in Ref. [11], who specify that once Section I
requirements are met and the data reports are signed, Section I no
longer controls the repairs and alterations. In many jurisdictions,
the NBIC assumes responsibility and provides the rules to follow.
The maintenance personnel should know or otherwise determine
if the jurisdiction is an NBBI member and if that jurisdiction
requires welded repairs and alterations to be performed by an
organization holding an NBBI R Symbol Stamp Certificate of
Authorization.
In the NBIC-mandated jurisdictions, to verify whether or not
the component needing welded repair or alteration is subject to the
rules of the NBIC [4], the reader should refer to the ASME Code
Section I Fig. PG-58.3.1a for drum-type boilers or Fig. PG-58.3.2
for forced-flow steam generators [2]. The drawings in these figures
show what is boiler proper and what is boiler external piping and
joint. If the components to be weld-repaired or altered conform to
these two drawings, the R Symbol Stamp applies and the repair
organization must necessarily be a Certificate Holder.
If the Owner–Operator organization has a maintenance group,
it is possible (if the Owner–Operator believes it to be beneficial)
to apply for and obtain the NBBI R Symbol Stamp Certificate
of Authorization. As an R Symbol Stamp Certificate Holder,
the Owner–Operator is permitted to perform welded repairs and
alterations, including the emergency repair of boilertube leaks.
However, to qualify for the R Symbol Stamp Certificate of
Authorization, the Owner–Operator must have (as a minimum)
qualified personnel including welders; qualified welding procedures; acceptable repair and/or alteration procedures; an acceptable
quality control or quality system program; and a third-party
inspection agreement with Authorized Inspection Agency (e.g., the
Hartford Steam Boiler Inspection & Insurance Company). In lieu
of the Authorized Inspection Agency, the Owner–Operator may
choose to be an NB O/U Inspection Organization that provides its
own repair inspections and in service inspections.
2.9.2
Maintenance
The purpose of this section is clearly stated in its first
paragraph—namely, that this section assists the maintenance group
in the prevention of unscheduled outages by defining the potential
trouble spots and conditions that should be checked during
scheduled maintenance outages or overhauls. It is stressed that
because this presentation is in general terms, the manufacturer’s
literature should be reviewed for detailed requirements.
Listings of maintenance checks are presented by component
based on historical data of items requiring maintenance attention.
(The actual checklist format is given in the Nonmandatory
Appendix A.) Owner–Operator personnel can use these checks as a
basis to create new maintenance checklists, or for examination and
overhaul procedures and also the Owner–Operator maintenance
program. Despite the many reminders for the reader to refer to the
manufacturer’s literature, these listings are quite comprehensive
and worth studying. However, Section VII will be enhanced
if it took the extra step and provided the answers to why each
maintenance check item was necessary. For example, why do you
check the condition of burner throat refractory, or why check for
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 2-27
slag build up on refractory? With more “answers to why,” Section
VII would be a “go to” book.
Operating checks related to maintenance are also presented
to prevent unscheduled shutdowns simply because the operators
are the personnel using the equipment and able to see firsthand
the actual operating conditions. The checks identified in this
section and in Nonmandatory Appendix A help to promptly detect
problems that usually can be corrected before they become serious.
The applicable component checks should be reviewed, from
which Owner-Operator procedures should be developed, if they
are nonexistent, or otherwise improved. In many cases, OwnerOperator examination and overhaul procedures were developed
many years previously and thus have not been reviewed to
incorporate latest developments.
PERTAINING TO ALL STEAM BOILERSSUBSECTION 2
2.10
PROTECTING HEAT TRANSFER
SURFACES—ARTICLE 200
Most power plant personnel understand that water treatment and
monitoring of the water used in the boiler and auxiliaries are critical
in preventing boilertube failures and internal corrosion damage. As
with the other Articles, this one provides a good introduction or
review of the control of chemical conditions within power boilers.
Eight headings are covered, and under each heading Section VII
attempts to do the following:
(1) state the type of water treatment problem;
(2) describe how each problem may be recognized; and
(3) provide information about how these problems may be
corrected.
Many references are available for further study; see [5], [12],
and [13], for example.
2.10.1
Internal Cleaning of Boilers
This section briefly discusses the internal cleaning of boilers,
including detergent cleaning (alkaline boilout), chemical cleaning
(via acids or solvents), and mechanical cleaning. This section
specifically refers to new boilers or new construction. Both
detergent cleaning and chemical cleaning are part of the standard
start-up procedure for most new boilers, for they remove the
manufacturing and erection contamination. Of interest to note is
that boilers operating under 900 psig (6 MPa) are not chemically
cleaned to remove mill scale but only detergent-cleaned because
the operating temperature does not warrant acid or solvent cleaning.
This section is short, considering the importance of cleaning.
The manufacturer’s instructions and the expertise of the chemical
cleaning companies are expected to be used extensively. However,
adequate information is given in this section for understanding
why cleaning is necessary.
Inservice boiler internal cleaning follows basically the same
procedure as for new boilers; however, items needing further
consideration do exist. Inservice boilers mainly involve chemical and/
or mechanical cleaning; detergent cleaning is rarely performed unless
there is a need to remove oil and grease. For example, an intrusion
of oil during operation or if a considerable portion of the boiler was
replaced would both necessitate detergent cleaning. Replacing large
sections of waterwall-tube panels justifies detergent cleaning for the
removal of installation contaminants and shipping preservatives. The
retubing of firetube boilers also falls into this category.
This section mentions that taking tube samples and analyzing
the deposit is essential in the cleaning of inservice boilers. The
chemical cleaning company receives representative samples
of tube sections and experimentally determines if cleaning is
necessary and, if so, which cleaning solution is optimal. (Usually
this is a trial-and-error procedure.) In mixed-metal condensatefeedwater systems, waterwall-tube deposits may include an
adhering layer of copper, in which case the chemical cleaning is
a two-process operation with the second cleaning process used
to remove the copper coating. Therefore, taking waterwall-tube
samples essentially have the following two purposes:
(1) to determine the amount and composition of the internaltube deposit, and
(2) to determine which chemical cleaning solution is best.
It is very important where the tube samples are taken and how
many are taken for analysis. If specific boilertube problems did
not occur, and if no particular areas to target exist, tube samples
normally are taken in the highest heat flux area. For oil-fired
watertube boilers, this may be approximately 2 ft. (.6 m) above the
top burners along this elevation of the furnace. However, for boilers
experiencing tube failure from overheating problems, caused by
the combination of internal deposits and flame impingement tube
samples may be taken in the waterwall where the signs of flame
impingement are most distinct.
It is obvious that selecting the correct tube samples for analysis
is not guaranteed, for random samples are taken with the hope
that they represent typical boilertube conditions. The more tube
samples taken, the better the chance of getting a correct sample;
for instance, many boiler operators take at least four tube samples
for the cleaning analysis. However, the more tube samples that are
taken, the more work that is required in replacing the removed tube
sections. A domino effect may be initiated, whereby in addition to
creating more work there is a greater chance of there being defective
welds when replacing the removed areas and also a greater chance
of there being more areas where the tube weld root causes water
flow disturbances upstream, allowing deposits to collect there.
It is important that as a minimum, the boiler manufacturer’s post
construction chemical cleaning piping setup for the new boiler
be followed for the inservice boiler cleaning. The manufacturer
should know how to ensure that the cleaning fluids reach all areas
of the boiler. However, should any flow problems not anticipated
by the manufacturer occur, the boiler operator engineering and
chemical personnel must be sufficiently knowledgeable to make
the proper adjustments for the flow of the cleaning fluids to reach
all areas of the boiler.
Nonetheless, the boiler operator engineering and chemical
personnel should evaluate and be aware of the possible restrictions
the different flow paths the chemical cleaning fluid may have
from the downcomers to and up the wall tubes. The longer paths
or circuits with multiple bends will have less flow through them
during operation and cleaning. These circuits will most likely have
more deposits and will require more cleaning effort. In most cases
a forced flow cleaning system with external heating is necessary
to clean these longer circuits. The traditional natural circulation
chemical cleaning method does not provide adequate cleaning for
the larger utility boilers with differing circuit configurations. This
method uses the existing burners to provide the natural circulation
to move the chemical cleaning fluid through the boiler. The
2-28 t Chapter 2
circuits with the lesser flow resistance will continuously receive
the cleaning fluid, while the circuits with the most flow resistance
will get very little flow.
In areas of questionable flow and/or in tube-damaged areas, it
may be prudent for one to install flanged-cleaning-tube sample
pieces. These are tube sections routed outside of the waterwall with
isolation valves and flanges so that the tube sample can be removed
and visually examined to monitor the cleaning process—especially
helpful when removing an adhering layer of copper.
One should remember that in jurisdictions where welded repairs
and alterations follow the NBBI R Symbol Stamp requirements,
chemical cleaning piping additions within the boiler proper and
boiler external piping follow specific procedures and requirements.
The O/U Commissioned Inspector or Authorized Inspector must
be involved in these processes.
Of course, with environmental regulations becoming more
stringent, the “environmental” engineer or consultant must be
involved for both possible air and water discharge concerns and
permitting.
2.10.2
Laying-Up of Boilers
Older, less-efficient boilers are being taken out of service and
stored for future use. In areas where shortage of generating capacity
has been experienced—and the reserves are still marginal—utilities
may choose to not eliminate these boilers until it is certain that they
will not again be needed; such boilers are being laid-up or stored.
Similarly, certain industrial processes may operate only during
certain times of the year so they may also be laid-up or stored for
the remainder of the year.
This section provides useful information for all sizes of boilers:
both watertube and firetube. In addition, it provides the reader
with available options. It is the boiler operator’s responsibility to
locate and obtain the references necessary for detailed information.
Members can go to the EPRI publication [6]; otherwise the boiler
manufacturer can be consulted.
2.10.2.1 Waterside There are two methods of laying-up or
storing boilers, both of which depend on the length of storage time
and climatic conditions. These methods are the wet lay-up method
and the dry lay-up method.
The wet lay-up method is recommended for shorter periods (4
days to 2 weeks), at which time the boiler may be needed on short
notice (during standby) and where freezing is not a concern. This
section gives recommendations for boilers operating below 1,000
psig (7 MPa) and those operating above 1,000 psig (7 MPa). In
either case, the goal is to minimize the amount of oxygen in the
water; this is accomplished by initially adding an oxygen scavenger
to the boiler water to minimize oxygen content, and it is also
necessary to keep the pH reading close to 10 to minimize hydrogen
ions and electro-chemical reactions. The wet method also has two
different applications: the boiler and superheater stored and filled
to the top, and the boiler stored at normal operating water level
with the superheater empty.
In the first application, to prevent oxygen infiltration during the
storage period, the boiler is filled to the top (including superheater
tubes) and the pressure is maintained greater than that of the
atmosphere. A nitrogen pressure or cap of 5 psig (35 kPa) can be
applied and maintained during the storage period. Regardless of
whether one uses a boiler pressure or a nitrogen cap, the pressure
gage should be monitored at least weekly to ensure positive
pressure throughout the boiler. Maintaining a nitrogen cap can be
difficult if not impossible to maintain for older boilers.
In the second application, the boiler can be stored with the water
at the normal operating level and with the superheater empty. With
this method, the water is treated with a sufficient amount of an
oxygen scavenger and a 5 psig (35 kPa) nitrogen cap is maintained
throughout the boiler and superheater spaces. Again, the goal is to
minimize the oxygen concentration in the water and in the empty
spaces, as well as to minimize air in-leakage.
The dry lay-up method is recommended for longer storage periods
(greater than 2 weeks) where the boiler is not on stand-by and where
freezing may be a concern. Three separate methods of dry layup are
recommended: the thoroughly-dried-with-desiccant method, the
circulated-dry-air method, and the nitrogen-fill blanket method.
In the thoroughly-dried-with-desiccant method, it is critical that
the boiler be dried thoroughly and kept dried throughout the storage
period. A desiccant or a certain amount of moisture-absorbing
material must be placed in the drums and replaced periodically,
and all openings must be tightly closed. Although these tasks may
seem easy, it is not at all that simple to ensure that all boiler internal
surfaces have been dried. In addition, there is a tendency for one to
forget about replacing the moisture-absorbing material on schedule.
In the circulated-dry-air method, the boiler must also be dried
thoroughly before commencing the storage and air circulation. The
air must flow over all areas, although to have it reach all areas may
seem impossible.
The nitrogen-fill blanket method obviously is the most appealing
method used and is applicable to large industrial and utility boilers.
Nitrogen gas is filled as the boiler is drained, and a 5 psig (35 kPa)
nitrogen gas pressure is maintained throughout the storage period.
Oxygen in water is minimal, and air in-leakage is prevented with
the 5 psig (35 kPa) nitrogen pressure. Operating or maintenance
personnel must remember to maintain this 5 psig (35 kPa) pressure.
Maintaining a nitrogen cap or blanket can be difficult for boilers
in service for many years. Closed valves do not seal tightly. Safety
is a concern if personnel need to enter the boiler spaces; therefore,
the proper amount of oxygen must be present throughout the boiler
spaces to be entered when personnel enter the boiler.
Utilities have used vapor phase corrosion inhibitors (VPCI) as
a dry lay-up option. The VPCI chemicals are proprietary having
been around for years. A utility has reported its use for boiler lay-up
during a long outage for generator repairs. After draining the boiler
the VPCI powder was dusted in the steam drum using an air horn,
and the drum shut tight. The boiler was rinsed before the boiler went
back on line. The rinse water may contain ammonium benzoate;
therefore, disposal must be dealt with accordingly. Not seeing VPCI
discussed reinforces the need to review and update Section VII
regularly with the other ASME Boiler and Pressure Vessel Codes.
2.10.2.2 Fireside This section is useful for any condition and
situation; it is not applicable solely for layup or storage. Boiler
operators may apply the information in this section for the firesides
during overhaul outages whether they are for only 2 wk. or for
longer than 8 wk. Although short, this section provides useful
information concerning possible fireside corrosion problems and
their solutions.
A fundamental fact is that sulfur-bearing fuels create corrosion
problems to surfaces in contact with the flue gas and also to surfaces
that receive the runoff of the boiler washwater. Wherever there is
refractory—especially old, worn refractory—the possibility exists
that the ash deposits will get into and between the porous, crumbly
refractory and metal surfaces. During the boiler wash performed
during overhauls, this ash deposit is wet and may remain wet or
damp throughout the overhaul outage.
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 2-29
Boiler washes for layup or overhauls should be a three-step
operation such as follows:
(1) water-wash with suitable pressure equipment;
(2) neutralize all surfaces using an alkaline solution (1% sodium
carbonate [Na2CO3]); and
(3) dry all surfaces.
Owner–Operators should evaluate the process suitable for their
needs. Some may neutralize, wash, and dry before an overhaul.
With this process the boiler and air heater are first soaked overnight
using an overhead spray system with an acid neutralization
solution. Then the boiler is washed.
During the layup, the accepted practice is to maintain a maximum
50% relative humidity.
The reader may use the information provided in section 200.9,
“Fireside Conditions,” to supplement this short section, for 200.9
contains information about some severely corrosive elements
of coal and fuel oils. This section provides the fundamental
information by reviewing the various publications written about
the subject.
2.10.3
Deposits and Internal Corrosion
This section discusses the water-touched boilertube internal
surfaces—mainly the waterwall tubes, which experience the high
heat flux from radiant heat. In ‘Fundamentals’, Article 100, natural
circulation was explained. If the flow created by natural circulation
is not able to sufficiently remove the heat from the burners, the tube
metal temperature design limit will be exceeded and overheating
damage will occur. This section discusses situations when deposits
(i.e., scale, sludge, and oil) on the inside surface of the watertube
boilertubes can impede the transfer of heat from burner flame to
the water or to the steam-water mixture flowing inside the tubes.
In this discussion of the aforementioned deposits and internal
corrosion, damage has a strong relationship with these deposits.
Similar comments apply to the waterside surfaces of fire-tube
boilers.
2.10.3.1 Deposits Scale, sludge, and oil deposits are discussed.
It is apparent that the title of section 200.4.2 should be “Sludge
and Oil.” Scale and sludge are highly dependent on the quality of
the water source. Most smaller boilers do not have pretreatment
facilities such as demineralizers that remove impurities (minerals
and salts) by ion exchange; the most they may have are filters to
remove particles from the water source. Their water treatment to
control scale and sludge is based on proprietary additives provided
by water treatment companies. In many cases, some form of
phosphate is added to react with the water impurities, helping to
form soft compounds that do not adhere to the tube surface and can
be removed only by adequate blowdown.
Other sources of deposits include the corrosion products of the
“preboiler” equipment including the condenser, feedwater heaters,
and associated piping. Air in-leakage can accelerate corrosion
of the carbon steel surfaces. For mixed-metal (i.e., copper and
steel) feedwater heaters, the air in-leakage, oxygen, and ammonia
accelerate copper tube corrosion, the products of which enter
the boiler and, under certain conditions, will deposit and adhere
especially to the inside surfaces of the boilertubes that face the
fires.
2.10.3.2 Internal Corrosion Besides creating an insulating effect
and causing the boilertube metal to overheat, deposits can act as
sponges, concentrating certain types of corrosives against the tube
surface to cause “underdeposit corrosion.” This section discusses
some forms of underdeposit corrosion including caustic corrosion or
gouging, acid corrosion, and hydrogen damage. EPRI has published
several reports describing these failure mechanisms in detail [13].
2.10.3.3 Internal Deposit Monitoring and Control of Water
Treatment The two monitoring tools mentioned to monitor internal
deposit are embedded thermocouple and tube samples. Tube samples
were reviewed in previous sections. Embedded thermocouples have
been in existence for many years, but perhaps its cost discourages
more widespread use in power boilers. Nowadays you do not hear
about utilities making new embedded thermocouple installations to
monitor waterwall tube deposit build up. With the thermocouple
junction embedded in the fireside tube-wall, changes in temperature
can be monitored to track deposit buildup and therefore to suggest
when chemical cleaning is needed.
The two aforementioned monitoring tools are used to monitor
internal deposits after they are formed. Section 200.4.3 Internal
Deposit Monitoring, briefly mentions a deposit weight density
(DWD) range (20 g/ft2 to 40 g/ft2) when cleaning is needed. It
would be more useful if existing cleaning guidelines specifying
three ranges when (1) cleaning not needed, (2) should consider
cleaning, and (3) must clean are included. This detailed information
will specify that these three ranges are dependent on the boiler
operating pressure. Obviously, to minimize or prevent the internal
deposits from building up, the best tool is proper water treatment
or a good water chemistry control program. Such a program may
include the following:
(1) selecting the proper water treatment method, such as:
AVT (all volatile treatment)
CPT (congruent phosphate treatment)
EPT (equilibrium phosphate treatment)
OT (oxygenated treatment)
PT (phosphate treatment)
(2) establishing adequate control limits or ranges of the controlled items, such as the pH, oxygen, and chloride level;
(3) setting the proper locations and quantity of sampling points,
such as at condensate pumps, economizers, and steam
drums;
(4) providing modern, functional monitoring instrumentation
or meters;
(5) ensuring the proper training of all personnel involved with
items (1)–(4) of this list, including operators and chemists;
and
(6) ensuring that the program is working, with management
and all personnel participating in it.
A brief description of sampling and testing of water for boilers
is given in section 200.8, “Sampling, Testing, Controlling, and
Reporting of Analyses of Water.” In developing the water treatment
program, the responsible water chemistry personnel can refer to
Table 200.8.1-1, “Methods for Sampling of Water and Steam”;
Table 200.8.2-1, “Methods of Analysis for the Control of Water
for Boilers”; and Table 200.8.2-2, “Useful Tests for the Control
of Water for Boilers.” EPRI members have several publications
for personnel to reference in their program development [6].
Once formulated, instituted, and working, this water treatment
program will help to ensure that the water treatment does not cause
overheating or corrode boiler components.
It should be noted that Table 200.8.2-2 “Useful Tests for the
Control of Water for Boilers”, along with its notes is an informative
and handy guide for boiler operating personnel to get a basic
2-30 t Chapter 2
understanding of which chemicals are used to control corrosion,
deposits and carryover. Section VII can be enhanced further by
including a separate table listing and describing the use of water
treatment chemicals. Besides hydroxides, phosphates, and sulfites,
adding a discussion of polymers, chelants, and amines can make
Section VII a more handy reference.
2.10.3.4 Auxiliary Equipment Corrosion Section 200.5.6
“Auxiliary Equipment Corrosion” briefly describes feedwater
component “corrosion caused by dissolved gases, especially
oxygen, in the feedwater.” To keep Section VII current, it should
also include the “flow-accelerated corrosion (FAC) mechanism
in which a normally protective oxide layer on a metal surface
dissolves in a location of fast flowing water. The underlying metal
corrodes to re-create the oxide, and thus the metal loss continue
[14].” FAC is different from erosion-corrosion mechanism because
it does not involve impingement of particles causing a mechanical
wear on the surface. It has the opposite effect of corrosion caused
by dissolved gases (oxygen). The presence of oxygen helps to
prevent FAC.
FAC normally affects carbon steel piping. The use of chromemoly piping will minimize or eliminate FAC. Boiler operators with
more air inleakage conditions exist experience less FAC damages.
FAC is a concern because of the possibility of larger diameter,
higher pressure piping thinning and rupturing causing property
damage and injury.
2.10.4
Corrosion Cracking of Boiler Steel
There are three categories of corrosion cracking reviewed in this
section: stress-corrosion cracking, corrosion fatigue cracking, and
hydrogen damage. Stress corrosion, or caustic embrittlement, is
caused by a stress-corrosion combination and results in cracking
along the grain boundaries of the steel, whereas corrosion fatigue
is caused by cyclic mechanical or thermal stresses that result in
transcrystalline cracking or cracking through the steel grains.
Additional, more detailed information on these two types of
damage is provided; refer to the list of references [5, 13].
EPRI reports that the susceptibility of stress-corrosion cracking
is more likely in austenitic stainless steel material having contact
with hydroxides and chlorides [13]. Because stainless steels are
rarely permitted by ASME Section I [2] for surfaces in contact with
water, this type of damage normally is found in the superheater
sections.
In addition, EPRI reports that corrosion fatigue cracking is
found mainly in water-contacted boilertubes, including supply
and riser tubes and the economizer [13]. Since corrosion fatigue
cracking (CF) is a major boiler tube failure mechanism, this section
should be expanded to provide more information. This additional
information could be as follows: CF initiates on the inside surface
of the boiler tube, commonly at rigid attachments such as buckstays
and windboxes. Besides being transcrystalline or trans granular,
the cracking is longitudinal to the tube axis, usually multiple
and parallel. The common method to examine for CF is by video
probe examination requiring access into the tube. Research is being
conducted by organizations such as EPRI to perfect nondestructive
examination methods using ultrasonic and digital radiography
systems to eliminate cutting access windows in the boiler tubes. As an
example, an older boiler operated in a cyclic manner has tight 90 deg.
tube-bends in the economizer above the inlet header. During its later
service life, cyclic stress works on the existing residual stresses of
these tight bends, resulting in cracking at the sides of the bends where
the original bending had formed an egg-shaped bend cross section
with sharper stress risers on both sides. After the damaged bend is
removed, it is cut perpendicular to the crack. The visual examination
reveals the cracks at the sides of the bend originating from the inside
and corrosion products wedged inside the crack. To summarize, the
following appear to have influenced the cracking:
(1) cyclic stresses caused by on/off cycling;
(2) residual stresses and stress risers on the sides of the tight
90 deg. tube bends; and
(3) corrosive condition on the waterside.
The water treatment program records should be reviewed for the
dissolved oxygen and pH readings, especially for sampling points
near the economizer inlet. The EPRI report mentions that low pH
readings may promote hydrogen cracking or embrittlement at the
crack tip, thus increasing the probability of the crack opening even
further [13]. Of course, the level of oxygen in the boiler water can
affect the oxide scale growth as the cycling stress breaks off the
protective coating at the side of the tube bend.
An excellent description of hydrogen damage is provided in
this section. Hydrogen damage is included with internal corrosion
or under-deposit corrosion. Actually, hydrogen damage can be
included with both underdeposit corrosion and the stress-corrosion
group, but the description in this section is reasonable. Hydrogen
is the smallest atom appearing on the chemistry periodic table,
and because of its small size, it apparently has a tendency to enter
carbon steel grain boundaries and react with the carbon. In welding,
it is theorized that hydrogen ion can enter the heat-affected zones
(HAZ) of the weld and combine with other hydrogen ions in
the steel to form the larger hydrogen molecule. Under certain
conditions, and also because of the welded component loading,
the larger hydrogen molecule applies sufficient pressure to its
surroundings to cause cracking.
2.11
PREVENTING BOILER FAILURES—
ARTICLE 201
This Article briefly reviews much of the material discussed in its
preceding sections. The reader is reminded that the purpose of Section
VII is to promote safety in the use of power boilers. Throughout this
Chapter 2, safe, reliable power boiler operation, maintenance, and
examination are stressed. This Article reviews some conditions that
affect this safe, reliable operation, maintenance, and examination.
It reviews the four general classifications of boiler failure, which
are grouped as follows:
(1)
(2)
(3)
(4)
caused by overpressure;
caused by high or low water level
caused by structural weakening; and
caused by errors in the operation of combustion equipment.
In the discussion of overpressure, the equipment required to
prevent boiler failures caused by overpressure is reviewed together
with how the equipment can be misused. The rest of this subsection
reviews precautions to be taken against conditions such as furnace
explosions or implosions.
2.11.1
Overpressure
The equipment or instrumentation included for the prevention of
overpressure boiler failure includes the following:
(1) steam pressure gages;
(2) pressure relief valves; and
(3) fusible plugs.
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 2-31
The operation and maintenance information provided on the
listed equipment is very useful. Even the most experienced boiler
operator may find some of the information new and reasonable.
The Owner–Operator can always use the information provided as
an instruction manual or as a source of review.
Pressure gages are covered in section 103.6. In this section,
operational errors and maintenance errors of pressure gages
are stressed. One error includes the failure to periodically test
for accuracy or instrument calibration. Many boiler operators
fail to verify that pressure gages are accurate; they may rely on
comparison with uncalibrated pressure gages already installed
throughout the boiler unit.
Pressure relief valves are covered in detail in Article 103, section
103.1 and 103.2.
Fusible plugs are covered in section 103.9.
2.11.2
High or Low Water Level
Gage glasses are also discussed in section 103.4. In this section,
the operational and maintenance errors of water glasses or gage
glasses are stressed, and more useful basic information is provided.
(1) water glasses or gage glasses;
(2) high- and low-level alarms;
(3) automatic trips;
Many boiler operators fail to test water columns and gage glasses
on a regular basis—if at all. Level alarms should be tested at the
same time that the water columns are blown down. Most boiler
operators understand readily that ASME Section I PG-60.1, “Water
Level Indicators,” permits the remaining gage glass to be shut off
but maintained in serviceable condition when both remote level
indicators are in reliable operation [2]. Such activity constitutes
“seeing is believing”-type thinking. However, it is possible that
many boiler operators neglect this remaining gage glass because
the lights are broken, the glass is dirty, the shut-off valves are frozen
shut, and the bottom portion is plugged with debris. Many operators
also forget the “locked or sealed open” requirement of ASME
Section I PG-60.3.7 for the first valves off of the steam drum [2].
A common misunderstanding pertaining to gage glasses concerns
“when the direct reading of gage glass water level is not readily
visible to the operator in the area where immediate control actions
are initiated.” Many boiler operators still believe that a system of
mirrors or fiber optic cable system is required. Section VII can
have added value if it included clarifications such as mentioning
that two independent, reliable remote level indicators will satisfy
this “direct reading” requirement making mirrors and fiber optics
unnecessary.
2.11.3
Weakening of Structure
The review is begun in this section by listing its three categories
of failure caused by weakening of the structure:
(4) weakening of pressure parts;
(5) failure of supports; and
(6) mechanical damage.
Then, this section lists and reviews conditions that cause weakening of the pressure parts. These conditions include the following:
(1) overheating;
(2) loss of metal from corrosion;
(3) weakening of the furnace from improper combustion or
flame impingement; and
(4) soot blower erosion.
The review on the weakening of pressure parts begins with
the boiler start-up, then proceeds to cover many necessary
precautions. Again, it is stressed that the boiler operator must
use the proper procedures (and checklists) to ensure safe, reliable
power boiler operation. It is highly recommended that checklists
for boiler start-up be developed and followed during every startup period.
The review continues with coverage of control of water level,
erosion (via soot blowers), internal corrosion, external corrosion,
boiler shutdown, boiler out-of-service time, failure of boiler and
piping supports and mechanical damage. Although this section
is essentially a review of the preceding sections, it does contain
some precautions not previously discussed that the reader will
find useful. Examples of such precautions are the sequence for
operating the double blowdown valves; the necessity of not using
waterwall-blowdown valves during boiler operation; and the need
to repair leaks at thick-walled components to prevent erosional
damage.
2.11.4
Operation of Combustion Equipment
Because of the hazard from explosion when fuels are burned,
this section notes that the review in Article 201 is not intended
to provide detailed safety rules governing the design, installation,
operation, and maintenance of fuel-burning systems. For such
detailed information, the reader must consult other sources, such as
the ASME CSD-1 “Controls and Safety Devices for Automatically
Fired Boilers,” for use on small boilers under 12.5 million Btu/hr.
fuel input. The reader may also consult the appropriate section of
the NFPA 85 Boiler and Combustion Systems Hazards Code. The
section 102.2 “Fuel Burning Equipment” of, Article 102, “Boiler
Auxiliaries,” should be used for general recommendations and
precautions.
A reminder: Only properly trained operators familiar with the
fuel-burning equipment being operated should be in charge of the
boiler units.
2.11.5
Furnace Explosions and Implosions
It is noted that Furnace explosions may be averted if proper
precautions are taken to prevent the admission of unburned fuel
into the furnace. Purging the furnace with fresh air from outside
the furnace area is recommended for any situation where a
combustible mixture is or may be present within the boiler furnace.
When shutdown, be sure that fuel inlet valves are closed tightly
and do not leak. Remove oil guns and only reconnect them as each
is to be placed in-service.
A furnace implosion is the establishment of a sufficient negative
pressure in a furnace to produce damage to the furnace structure.
Large utility boilers are more susceptible to implosions due to their
large furnace wall area and the high suction-head capacity of their
induced draft (ID) fans. The most severe furnace implosions can
occur on oil- or gas-fired balanced draft units.
Because of the extremely fast time interval surrounding furnace
implosions, their prevention requires an automatic control response.
The following features should be provided in any furnace draft and
combustion control system:
(a) The airflow to a furnace must be maintained at its pre-trip
value and must not be prevented from increasing by following natural fan curves; however, positive control action to
increase airflow is not allowed by NFPA 85.
(b) The flow of combustion products from a furnace must be
reduced as quickly as possible following a unit trip.
2-32 t Chapter 2
(c) If the removal of fuel from the furnace can occur over a
period of 5 sec to 10 sec (rather than instantaneously), there
will be a reduction in the magnitude of the furnace negative
pressure excursion that follows a unit trip.
When considering the prevention of excessive negative pressure
excursions during main fuel firing, one should keep in mind the
related possibility of a furnace explosion and not negate any
control function used in its prevention. The effects of a fire-side
explosion are potentially more damaging to equipment and carry a
much greater risk of injury to personnel.
2.12
DOCUMENTS, RECORDS,
AND REFERENCES
In addition to identifying Section I, Power Boilers A-350 as the
location of all new boiler data forms required that may apply to the
boiler and boiler external piping, Section VII states that copies of
these documents as completed at the initial installation of the boiler
and other documents should be maintained as a file, not necessarily
at the boiler site.
Also, a list is provided of all documents referenced in Section
VII and the source for obtaining copies.
OTHER BOILER TYPES- SUBSECTION 3
2.13
FIRETUBE BOILERS, ARTICLE 300
In the firetube boiler, gases of combustion pass through the
inside of the tubes with water surrounding the outside of the tubes.
The advantages of a firetube boiler are its simple construction
and less-rigid water treatment requirements. The disadvantages
are the excessive weight per pound of steam generated, excessive
time required to raise steam pressure because of the relatively
large volume of water, and the inability of the firetube boiler to
respond quickly to load changes, again due to the large water
volume.
The added, unique or just different aspects of firetube boilers
from watertube boilers previously discussed in Subsection 1 are
described here. All differences are not discussed and Section VII
would be enhanced if added figures and discussions were included.
The discussion regarding Internal Examination, section 300.3, is
good example.
The items peculiar to the maintenance of firetube boilers
are listed and Nonmandatory Appendix A, Article 103 and 104
provides checklists for firetube boilers.
Some of the advantages are;
Compact Designs
No Stack Required
No Emissions
Quiet Operation
High Efficiency
Ease of Maintenance
There are two types of electric boilers;
Resistance-Element Electric Boilers
Electrode Steam Boilers
There are various approaches to applying these two basic types.
Five are pictured and discussed. Typical is Fig. 2-15, Basic Electrode
Steam Boiler with Jet Spray and Mechanical Control Shield.
The water quality and treatment varies and these requirements
are discussed as well as the maintenance requirements. All electric
boilers require periodic shut down for physical cleaning of the
heating elements.
The presentation in this Article is a must for anyone considering
applying electric boilers for the first time.
2.15
The only content of this Article are two specific sections that
apply to utility size boilers.
Section VII is the place for explaining some of the rules of Section
I, Power Boilers that apply only to the larger, utility size boilers.
This Article could be used or an Article added to address the unique
requirements of Heat Recovery Steam Generators (HRSG’s)
COAL-FIRES AND OTHER SOLID-FUELFIRED BOILERS-SUBSECTION 4
2.16
STOKER-FIRED BOILERS,
ARTICLE 400
2.17
PULVERIZED-COAL-FIRED BOILERS,
ARTICLE 401
These two Articles provide some cross sections and depictions
with the various elements named. An introduction only is provided
to these types of boiler firing. The manufacturers’ literature should
be referred to for a detailed explanation.
2.18
2.14
ELECTRIC STEAM BOILERS,
ARTICLE 301
Electric steam boilers generate steam by immersing resistance
heaters directly in the boiler water or by passing electric current
between electrodes immersed in the boiler water. Steam generation
and therefore pressure are controlled indirectly by varying electric power input. In applications where electric power is more
economically available than fossil fuels, or where combustion
of fossil fuels and the handling of combustion by-products are
unacceptable, electric boilers offer a viable alternative.
UTILITY BOILERS, ARTICLE 302
ASH REMOVAL, ARTICLE 402
The types of ash, bottom and fly, are presented and the types of
removal to bins are described. Including pictures would enhance
what little information is presented.
2.19
MAINTENANCE, ARTICLE 403
Short generic lists of Maintenance Checks are provided for
Stokers, Pulverized-Coal Fired Boilers and for Ash Removal
Systems. The manufacturers’ literature should be referred to for a
detailed explanation.
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 2-33
FIG. 2.15 BASIC ELECTRODE STEAM BOILER WITH JET SPRAY AND MECHANICAL CONTROL SHIELD (Source:
Fig. 301.3.3-1, Section VII of the 2015 ASME B&PV Code)
GLOSSARY- SUBSECTION 5
2.20
GLOSSARY
Many of the terms that may be used when referring to a power
boiler and associated facilities are defined in this Subsection. The
previous 3 “Subject Matter” Glossary’s were combined, added to
and definitions confirmed with the Lexicon of the American Boiler
Manufacturers Association (ABMA). This Subsection alone is
worth the price to have a copy of Section VII available.
2.21
FINAL NOTES
This chapter has repeatedly emphasized that ASME Section
VII contains valuable information for the power boiler opera tion,
maintenance, and examination personnel. Section VII is a practical
boiler book, a good review for experienced personnel and a good
teaching aid for less-experienced personnel. However, it cannot
possibly provide all the details for such numerous topics. Therefore,
manufacturers’ instructions and other reputable sources must
be consulted for a more complete understanding of each subject
presented. Procedures and check-lists for operation, maintenance,
2-34 t Chapter 2
and examination are critical requirements; they must exist, be used
regularly, and be reviewed periodically.
Finally, throughout this chapter omissions from Section
VII are noted and additions that would add significantly to
Section VII usefulness are noted. Section I Standard Committee
should consider these noted omissions and useful additions for
development and inclusion in future, even more complete Editions
of Section VII.
6. Steam: Its Generation and Use, Babcock & Wilcox, 40th ed., 1992.
2.22
10. Standards for Closed Feedwater Heaters; Heat Exchange Institute,
Inc., 1998.
REFERENCES
1. ASME Boiler and Pressure Vessel Code Section VI, Recommended
Rules for the Care and Operation of Heating Boilers; The American
Society of Mechanical Engineers.
2. ASME Boiler and Pressure Vessel Code Section I, Rules for the
Construction of Power Boilers; The American Society of Mechanical
Engineers.
3. ASME B31.1, Power Piping; The American Society of Mechanical
Engineers.
4. ANSI/NB-23, National Board Inspection Code; The National Board
of Boiler and Pressure Vessel Inspectors.
5. Bernstein, M. D., and Yoder, L. W., “Introduction to Power Boilers
Section I of the ASME Boiler and Pressure Vessel Code,” PVP
Conference, Honolulu, July 1995.
7. EPRI TR-107754, Cycling, Start-up, Shutdown, and Layup Fossil
Plant Cycle Chemistry Guidelines for Operators and Chemists; The
Electric Power Research Institute.
8. NB-18, Pressure-Relief Device Certifications; The National Board of
Boiler and Pressure Vessel Inspectors.
9. ASME Boiler and Pressure Vessel Code Section VIII, Division 1,
Rules for the Construction of Pressure Vessels; The American Society
of Mechanical Engineers.
11. Seat Tightness of Pressure-Relief Valves, ANSI/API Standard 527,
3rd ed., July 1991.
12. Kohan, A. L., Boiler Operator’s Guide, McGraw-Hill, New York,
4th ed., 1998.
13. Dooley, R. B., and McNaughton, W. P., “Boiler Tube Failures: Theory
and Practice,” EPRI TR-105261, Vols. 2 and 3, Water-Touched and
Steam-Touched Tubes, The Electric Power Research Institute, 1996.
14. Flow-accelerated corrosion, Wikipedia®, Wikipedia Foundation,
Inc.
CHAPTER
3
Part 2, Section II—Materials
and Specifications
Elmar Upitis, Richard A. Moen, Marvin L. Carpenter,
William Newell Jr., John F. Grubb, Richard C. Sutherlin,
Jeffrey Henry, C. W. Rowley and Anne Chaudouet1
3.1
HISTORY OF MATERIALS IN THE
ASME BOILER AND PRESSURE
VESSEL CODE
The first (1914) edition [1] of Rules for the Construction of Stationary Boilers and for Allowable Working Pressures was adopted
in the spring of 1915 [2]. The book consisted of 114 pages, of
which 35 pages—the first 178 paragraphs—were dedicated to
materials. Part I of the 1914 edition was dedicated to Section I
(Power Boilers). Material specifications were provided in Section I
for important materials used in the construction of boilers. Only
riveted construction was permitted; the specifications included the
materials permitted for rivets. The material requirement was that
the rivets be made of steel or iron and be manufactured to specifications written specifically for boiler–rivet steel or iron. It should
be noted that fusion-welded construction for pressure-boundary
parts was not permitted until the 1931 Edition of the ASME Boiler
and Pressure Vessel (B&PV) Code was published.
The materials, for the most part, were similar to those covered
by the specifications in the American Society for Testing and
Materials (ASTM); however, they were not duplicates. Meetings
were held between representatives of ASTM and the Boiler Code
Committee and, as a result, in the 1918 Edition of the Boiler
Code there was a much closer agreement between the material
specifications in the ASME Boiler Code and those in ASTM.
Specifications provided in Part I of Section I (Power Boilers)
included materials approved for use in the design and fabrication
of power boilers. The specifications included in the 1914 Edition
of the Boiler Code are shown in Table 3.1.1. For the most part,
Firebox-quality steel was to be used. (Steels were designated Firebox
1
Dennis Rahoi, Marvin L. Carpenter and Domenic A. Canonico were
the original authors of this chapter that was revised for the second and
third editions by Marvin L. Carpenter, Elmar Upitis and Richard A. Moen.
For the fourth edition Elmar Upitis, Marvin L. Carpenter, John F. Grubb,
Richard C. Sutherlin, Jeffrey Henry, C. W. Rowley and Anne Chaudoulet
contributed where as for this edition all of them except C. W. Rowley had
contributions for this fifth edition chapter revision. Part 3.6 of this chapter
in fourth edition is enlarged in scope and coverage and moved to chapter
40 of this fifth edition. – Editor
and Flange quality, the former having a higher quality than the latter
[3].) The specifications in the first edition of the Boiler Code were
developed in accordance with the steel-making and production
technologies in common use at that time and therefore bear little
resemblance to those in the current 2010 Edition of Section II.
The 1914 Edition of the Boiler Code included a Part I Section
II that was for boilers used exclusively for low-pressure steam and
hot water heating and hot water supply. The maximum allowable
working pressure for these boilers was limited to 15 pounds per
square inch (psi). Only one paragraph, 335, was dedicated to boiler
materials and stated that the rules for power boilers shall apply for
larger units and for the materials given in paragraphs 23 through
178. The use of flange quality steel was permitted for these boilers.
The determination of the maximum allowable working pressure
was based on the minimum tensile strength (TS) of the shell plate;
the thickness (t) of the plate; the inside radius (R) of the cylinder;
a non-dimensional efficiency factor (E), which is the ratio of the
strength of a unit length of riveted joint to the same unit length
of the solid plate; and a factor of safety (FS), which was 5 when
the 1914 Edition of the Boiler Code was issued. The equation for
determining the maximum allowable working pressure in psi was
TS * t * E
R * FS
The FS was defined as the ratio of the ultimate tensile strength of
the material to the allowable stress. It is this definition that resulted
in the idea of a factor of safety applied to the minimum tensile
strength of materials used for B&PV Code construction. As noted
in the foregoing equation, the FS is in the denominator of the equation provided in the 1914 Edition; it is divided into all of the factors
in the numerator and, in reality, was not a material safety factor.
In 1914, there was only one plate material (Specification No. A
30-14) from which boilers could be fabricated—the Firebox-quality
carbon steel. The required chemical composition of this boilerplate
steel is given in Table 3.1.2; the required mechanical properties are
given in Table 3.1.3. The analysis in Table 3.1.2 can be compared
to the steels listed in Table 3.1.4. The minimum room temperature
tensile strength for the boilerplate was 55,000 psi, which is the TS
value used in the equation to determine the maximum allowable
3-2 t Chapter 3
TABLE 3.1.1 MATERIAL SPECIFICATIONS IN THE 1914 EDITION OF THE
BOILER CODE AND THE SOURCE FROM WHICH THEY WERE DEVELOPED
TABLE 3.1.2 CHEMICAL COMPOSITION OF
THE BOILER PLATE STEEL (S-1) PERMITTED IN THE
1914 EDITION OF THE BOILER CODE
working pressure. Interestingly, the permissible range in tensile
strength in the material for the steel plate permitted in the 1914
Edition of the Boiler Code was much tighter (8,000 psi versus
20,000 psi) than what is permitted today.
In the 1914 and 1918 editions of the Boiler Code, the material
specifications were included in paragraphs that were not specifically numbered or identified. With the adoption of Section VIII
(Code for Unfired Pressure Vessels) in 1925, it was recognized that
a reference for materials would be necessary for that document,
so in the 1924 Edition of the B&PV Code, a separate materials
section—Section II (Material Specifications)—was published. It
was bound with Section I (Power Boilers) and Section VI (Rules
for Inspection).
With the adoption of a separate materials section, it became
prudent to identify the specifications with numbers. The decision
was made to number the specifications, beginning with S-1 and
continuing them to S-xx. These specifications were derived from
the ASTM specifications; often, a direct reference was made to
the corresponding ASTM specification. In 1927, copper and brass
materials were added to the materials in Section II. The use of the
S-designation for B&PV Code Material Specifications (initiated
in the 1927 Edition) continued through the 1931 Edition, although
most specifications were in close agreement with the ASTM
specifications upon which they were based.
TABLE 3.1.3 THE REQUIRED MECHANICAL PROPERTIES OF THE
BOILER PLATE STEEL PERMITTED IN THE 1914 EDITION OF THE BOILER CODE
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-3
TABLE 3.1.4 CHEMICAL COMPOSITION OF SA-516, GRADE 55 IN THE 2010 EDITION OF SECTION II, PART A
Also contained in the 1927 Edition were Sections I, II, and VIII, the
latter covered in paragraphs S-1 to S-263. By 1931, nearly all of the
material specifications were identical to their ASTM counterparts.
The 1930 Edition of the Boiler Rules, which included Section II, cost
$2.50; a complete set of the Code Books cost $5.00. There was a 20%
discount for ASME members. Addenda were sold separately.
Shortly after the introduction of Section VIII (Code for Unfired
Pressure Vessels), ASME and the American Petroleum Institute
(API), formed the joint API–ASME Committee on Unfired Pressure Vessels in late 1931. The goal of this joint committee was to
prepare a code, adapted to the needs of the petroleum industry, for
safe practice in the design, construction, inspection, and repair of
unfired pressure vessels for petroleum liquids and gases [4]. After
much discussion, and with concessions made by both groups, the
joint API–ASME Code (Unfired Pressure Vessels for Petroleum
Liquids and Gases) was issued in late 1934 as an addition to Section VIII (which had existed since 1925). The API–ASME Code
was discontinued in 1956.
The API–ASME Code was unique in that it used a maximum
allowable working stress based on 25% of the minimum specified
ultimate tensile strength of the plate material used to fabricate the
shell of the vessel. The equation for calculating the thickness of
the cylindrical shell did not contain a FS factor; instead, it used a
maximum allowable stress value based on 25% of the minimum
specified tensile strength to determine wall thickness. The success
of this approach was an important consideration when the decision
ultimately was made to reduce the FS to 4.
The plate and forging materials permitted for the fabrication of
vessels manufactured in accordance with the API–ASME Code were
all covered by ASTM material specifications. The piping material for
the most part also was governed by the ASTM specifications, but materials from two API specifications were also permitted. There were
no specifications provided in the API–ASME Code; the approved
materials were instead identified by their respective ASTM-, API-,
and American National Standards Institute (ANSI)-Specification
numbers on a single page included in the volume as Section S.
During the late 1920s, the Boiler Code Committee began to
seriously consider the use of welding as a method for joining
pressure-boundary materials. There was considerable discussion
among the committee members, and after extensive testing (which
included testing vessels fabricated by welding to failure [5]), fusion
welding was deemed acceptable for fabricating pressure parts for
use in ASME construction. Fusion welding of pressure parts was
first permitted in the 1931 edition of the Boiler Code.
The materials continued to be included as a separate section in
the 1930 edition of the Boiler Code. They were identified with
an S-number and, where appropriate, correlated with the ASTM
specification from which they were derived. For example, the S-1
specification for steel boilerplate is identified as ASTM A-70-27.
In 1931, Boiler Code users were invited to request materials other
than those permitted in Section II. Their requests were prompted
by the Boiler Code Committee’s desire to keep abreast of new
materials that could promote the state of the art of pressure-retaining
components. To accommodate the requests for new materials, in
1936 a special committee was assigned to review and consider the
acceptability of new materials. It was required that all requests
for new materials obtain the approval of this special committee.
Also in the 1931 edition, materials were deleted from Section
VIII and transferred to Section II, and references to materials for
Section VIII construction were made to specification numbers
in Section II.
In 1935, the first of the high-strength alloy steels were introduced
to the Boiler Code. The S-25 Specification—identical to ASTM
129-33, a carbon–molybdenum (C–1/2Mo) steel, and S-28, a
chromium–manganese–silicon (Cr–Mn–Si) steel—were permitted
for riveted construction, although they were not permitted to be
fusion-welded. Also, the chromium molybdenum (Cr–Mo) steels
and austenitic stainless steels were introduced during this mid- to
late-1930s’ time period. Specification S-34 (ASTM A-158-36),
published in the 1936 addenda to Section II, represented the first of
the Cr-Mo steels to be included in the Code; they were identified in
S-34 as P-1 (C–1/2Mo), P-3 (1.75Cr–1/2Mo), P-4 (5 Cr–1/2Mo–
1W), P-11 (lCr–1/2Mo), and P-12 (1.75Ni–1/4Mo). In addition,
S-34 contained an austenitic stainless steel, P-8, which was
essentially Type 304. The 1937 edition contained the first electric–
resistance–welded (ERW) tubing, S-32 (ASTM A-178-37). The
stabilized stainless steels were also introduced in this time period
through Code Case 834; these were the forerunners to Types 321
and 347 stainless steel. The 1937 edition of the Boiler Rules, which
contained Section II, cost $2.50; the entire set of Code Books cost
$5.50. ASME members received a 20% discount. Addenda were
sold separately.
3-4 t Chapter 3
In the 1937 Edition of the Boiler Code, the Section II materials
were numbered through S-41. The 1940 Edition contained materials
through S-57 (in the 1941 addenda, there were materials through
S-62). The S-52 in the 1940 edition was identical to ASTM A-213;
it contained the Cr-Mo alloys T-11 (11/2Cr–1/2Mo), T-12 (1Cr–
1/2Mo), and T-22 (2 1/4Cr–1Mo).
Section II was first published as a separate book in the 1940
edition of the B&PV Code. Section II of the 1940 Edition cost
$2.00; the entire set of Code Books cost $8.50. ASME members
received a 20% discount. Addenda were sold separately.
The S-number procedure for identifying Section II materials
was replaced in the 1943 Edition with a direct reference to the
ASTM Specifications. The S-designation system was maintained,
but an ASTM Specification number was added after the S—S-52,
for instance, was revised to SA-213, with A 213 being the ASTM
Specification that was the basis for S-52. This method was used
for all ferrous materials (except one material, S-4). For nonferrous
materials, the S-number was placed before the ASTM B-number.
In the 1945 addenda, all materials were listed by an SA- or SBnumber. Identifying materials approved for ASME Code construction became easier after the publication of the 1943 Edition of the
Code; in particular, a material identified with an SA or SB before
the specification number meant that alloy had been approved by at
least one Section of the ASME Code. Table 3.1.5, originally from
the 1943 edition of ASME Power Boilers, provides the correlation [6] between the S-number and the ASTM Specification from
which it was derived. The 1943 Edition of Section II cost $2.25;
the entire set of Code Books cost $9.00. ASME members received
a 20% discount. Addenda were sold separately.
It is interesting to note that twenty of the forty-two S-ferrous
Material Specifications that existed in 1943 and earlier are in the
current 2010 Edition listed in Section II, Part A; indeed, many
of them continue to be the preferred tube and forging materials
for the fabrication of pressure parts for boiler applications. These
include SA-192 and SA-210 (seamless carbon steel tubing), SA178 and SA-250 (ERW carbon and alloy-steel tubing), SA-105
(carbon steel forging), and SA-182 (forged and rolled alloy steel).
The 1946 Edition of Section II cost $3.50; the entire set of Code
Books cost $12.50. ASME members received a 20% discount. Addenda were sold separately.
Carbon steel plate (S-1) was among the first materials in the 1914
Edition of the Rules for the Construction of Stationary Boilers and
for Allowable Working Pressures; the analysis for the S-1 plate
material for riveted construction is provided in Table 3.1.2. ASTM
A-212-39 (S-55) was put into Section II in the 1940 Edition of the
Code. There were two grades in S-55: A and B, each with two different minimum tensile strength requirements controlled by carbon
content. The maximum thickness permitted in S-55 was 4 1/2 in., a
limitation that was dictated by the capabilities of radiography (RT)
at that time. As the state of the art of RT advanced, this limitation was
removed. For example, in the 1952 Edition of the Code, the maximum thickness was raised to 6 in.; later, in 1956, it was raised to 8 in.
In the ASTM A212-39 Specification, no reference was made
to coarse or fine grained melting practices, and fracture toughness
TABLE 3.1.5 CORRELATIONa BETWEEN THE REVISED SECTION II SPECIFICATION NUMBERS
OF THE 1943 EDITION OF THE BOILER AND THE PREVIOUS SECTION II NUMBERS
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-5
was a laboratory curiosity rather than a consideration in the
material specifications. The catastrophic failures of the Liberty
ships during World War II highlighted the need for considering
the potential for brittle fracture in material selection. The postWorld War II studies that focused on the ship fractures and other
brittle failures were reported at a symposium in Atlantic City,
New Jersey, in June 1953 [7]. The information reported at the
symposium was the culmination of extensive and ongoing testing
since shortly after World War II. These data were the basis for
the ASTM Specification A-300 (Specification for Steel Plate for
Pressure Vessel Service at Low Temperature), which provided
minimum Charpy V-notch (CV) impact requirements for plate
steels intended for low-temperature service. Section II adopted
A-300 in the 1949 Edition. The ASTM A-300 required a minimum
CV value of 15 ft-lb at –50°F for a carbon steel plate. The SA300 referenced A-370 (Standard Test Methods and Definitions
for Mechanical Testing of Steel Products), which was included
in Section II in the 1956 Addenda. The 1949 Edition of Section
II cost $5.00; the entire set of Code Books cost $14.50. Addenda
were sold separately.
In 1952, the SA-212 Specification included a requirement that
the plate material supplied in accordance with this specification
must satisfy ASTM A-20 (Tentative Specification for the General
Requirements for the Delivery of Rolled Steel Plates of Flange and
Firebox Qualities). Also, it was required in SA-212 that plates
intended for low temperature service must meet the impact requirements in SA-300. SA-212 could be purchased to a fine–grain–
melting practice—and subsequently normalized and tempered—
for low temperature service, or purchased to a coarse grain melting
practice; the single specification permitted the manufacture of both
plate grades.
The carbon steel plate grades contained in the SA-212 Specification remained the materials of choice for low temperature service
for boiler drums and pressure vessels, with low temperature in
this context relating to temperatures below those at which timedependent mechanical properties control the service life of a pressure boundary component. As mentioned previously, the SA-212
single material could be melted in accordance with fine grained or
coarse grained practice. The material melted to fine-grain practice
had to satisfy the requirements of SA-300. From 1962 to the time
that the 1968 Edition of Section II was issued, the SA-212 Specification was deleted by ASTM and thus from Section II; it was
replaced with two specifications. The SA-212 steel plate melted
to coarse-grain practice was replaced with SA-515 (Specification
for Pressure Vessel Plates, Carbon Steel, for Intermediate and
Higher Temperature Service) and the SA-212 steel plate melted
to fine-grain practice was replaced with SA-516 (Specification for
Pressure Vessel Plates, Carbon Steel, for Moderate and Lower
Temperature Service). These two specifications—along with
SA-299 (Specification for Pressure Vessel Plates, Carbon Steel,
Manganese-Silicon), which has slightly higher room-temperature
strength—were first published in the 1949 Edition of Section II.
They continue to be used today as the carbon steel plate materials
of choice for boiler and pressure vessel applications. There are
four grades in SA-516: 55, 60, 65, and 70. (The grade number
represents the minimum tensile strength requirement, in ksi, at
room temperature.)
It is interesting to compare the chemical composition and
mechanical property requirements for S-1 steel plate, the plate
material permitted in the 1914 Edition of the Boiler Code, and the
“technologically updated” SA-516, Grade 55.
Tables 3.1.4 and 3.1.6 provide the chemical composition and
mechanical property requirements, respectively, for Grade 55,
which has room-temperature-strength requirements (minimum
55,000 psi) similar to those of the S-1 steel plate in the 1914 Edition
of the Boiler Code. The permissible range for the tensile strength
in the S-1 Specification was much tighter (55,000–63,000 psi) than
what is required in SA-516, Grade 55 (55,000–75,000 psi).
Alloy steels were first included in Section II in the mid-1930s.
The 1933 Specification S-25 contained C–1/2Mo, and in 1935, steels
containing Cr (S-28 Cr–Mn–Si steel) were accepted by Section II,
although they were not permitted for welded construction. SA-213,
T-22 (2 ¼Cr–1Mo) tube steel, the most commonly used ferritic
tube material for elevated-temperature service, was added to
Section II in 1943.
The Cr–Mo steels, particularly 21/4Cr–1Mo, were the ferritic materials of choice for elevated-temperature service until the
development of the modified 9Cr–1Mo steel. This alloy was based
on the research of the Timken Roller Bearing Company [8], which
modified the straight 9Cr–1Mo through the controlled additions of
vanadium (V) and columbium (Cb).
The optimization of the Timken-modified 9Cr–1Mo alloy
was done in the early 1970s under the sponsorship of the Energy
Research and Development Agency, which later became the U.S.
Department of Energy [8]. This alloy was developed for use in
the liquid-metal fast-breeder reactor (LMFBR) program [10]. With
the demise of the LMFBR in the late 1970s, there was no apparent need for the alloy. Many might question whether the adoption of grade 91 for boilers was really fortunate or even desirable,
however, boiler designers recognized that the superior elevatedtemperature strength of the modified 9Cr–1Mo steel would be useful for boiler construction, particularly in applications where the
boilers would be cycled heavily. In addition to the higher strength
in the time-dependent temperature regime, it also provided resistance to oxidation to temperatures about 100°F higher than those
possible with 2 1/4Cr–1Mo steel. Moreover, the alloy was of interest for boiler construction because it promised the potential for
eliminating in some cases dissimilar metal welds between ferritic
and austenitic alloys, which was a recurring source of problems in
the Power industry. The original Code Case for Grade 91, which
covered only tubing for Section I applications, was approved in
July 1983. Today, the alloy is identified as Grade 91, and all product forms are permitted for Sections I, III, and VIII construction.
Grade 91 proved to be the first of a number of V- and Cb-bearing
alloys with excellent high-temperature strength, but with more
rigorous processing requirements, since these alloys depended
TABLE 3.1.6 THE MECHANICAL PROPERTY REQUIREMENTS FOR
SA-516, GRADE 55 IN THE 2010 EDITION OF SECTION II, PART A
3-6 t Chapter 3
for their superior elevated temperature strength on one specific
condition of microstructure. Currently, these advanced alloys, also
known as the Creep Strength-Enhanced Ferritic (CSEF) steels, are
permitted for ASME construction in Sections I, III and VIII. With
the exception of Grade 91, all of the other CSEF steels currently
are approved only as Code Cases. They include the alloys identified as Grades 23 (CC 2199), 24 (CC 2540), 911 (CC 2327), 92
(CC2179), 93 (CC2839), 122 (CC2180) and VM12 (CC2781).
In addition, Code Cases have been issued to cover the cast version of Grade 91 (CC 2192) and Grade 91 components fabricated
using HIP’d Powder Metallurgy technology (CC 2770). They have
now all been included in one or more of the ASTM specifications
and subsequently have been adopted in their counterpart ASME
(SA) specifications. A completely new ASTM Specification, A
1017/A 1017M Specification for Pressure Vessel Plates, Alloy
Steel, Chromium-Molybdenum-Tungsten has been written for the
plate materials included in Code Cases 2180, 2199 and 2327.
This ASTM Specification has been accepted by Section II and is
included in Section II Part A as SA-1017/1017M; Grades 23, 911
and 122 are included in SA-1017. The Grades 23, 92, 93 and 122
are included in SA-213. The pipe product form for Grades 92 and
122 are in SA-335.
As indicated above, one essential difference in this class of
so-called Creep Strength-Enhanced Ferritic (CSEF) steels, when
compared to the “standard” Cr-Mo steels—such as Grade 22—that
have been used for so many years for elevated temperature service
in ASME boiler and pressure vessel construction, is the fact that the
superior creep strength of the CSEF alloys is derived from the creation of one specific, metastable condition of microstructure during an
initial austenitizing (typically Grade 91 and many other CSEF steels
are air hardening, so the microstructure of the normalized material is
Martensitic, rather than pearlitic) and tempering heat treatment. Any
disruption of this condition of microstructure during subsequent processing of the material has the potential to substantially compromise
the alloy’s enhanced elevated temperature performance. As a result,
careful control of all processing operations, such as forming, welding,
heat treatment etc., is critical if the expected performance of the alloy
is to be realized. It is for this reason that major changes both to the
applicable material specifications and Code Cases as well as to the
Construction Codes have been recommended by Standards Committee II to insure that producers and manufacturers are made aware of
the importance of process control for these materials. For example,
beginning with the 2007 edition of the B&PV Code, for this class of
alloys the traditional Code practice of specifying only a minimum
temperature for any heat treatment operation has been modified and
well-defined temperature ranges have been established not only for
the initial Normalizing and Tempering operations that determine
the material’s basic condition but also for all subsequent sub-critical
thermal processing steps, such as post-weld heat treatment and postforming heat treatment. In addition, strict limits have been imposed
to control any inadvertent heating of the alloy during production or
manufacturing to minimize the risk of damage to the material prior
to initial operation. For the same reasons, controls on the amount of
strain induced during cold and warm forming operations have been
imposed to insure that the substantial reductions in creep strength that
can occur with high levels of cold/warm strain are avoided through
the appropriate post-forming heat treatments. New information regarding the long-term performance of this class of alloys is under
constant review by the SC II Working Group on Creep StrengthEnhanced Ferritic Steels, and additional modifications to Code rules
governing the processing of these materials will be made in the future
as the implications of this new information are fully understood.
These advanced high temperature ferritic alloys are receiving
considerable attention as viable candidates for the advanced steam
cycle power plants. Their use will increase dramatically over the
next few years.
Specifications for welding electrodes were first introduced into
Section II with the 1943 Edition. The specification for welding
electrodes and rods, SA-233, in that edition were based on ASTM
Specification A-233-42T. In 1949, three welding specifications
were included in Section II: SA-233, SA-251, and SA-316. In
1959, there were four ferritic and six nonferrous welding specifications; by 1962, there were seven nonferrous and five ferrous
welding specifications. The nonferrous weld materials were also
based on ASTM Specifications and were identified as SB followed
by the ASTM B-number.
In 1969, the AWS began publishing specifications for welding
rods, electrodes, and filler metals. The ASTM ceased writing welding specifications, and the ASME B&PV Code began to recognize
the AWS specifications. In the 1971 edition of the B&PV Code,
Section II contained three books: Part A, Ferrous Material Specifications; Part B, Nonferrous Material Specifications; and the newly
introduced Part C, Specifications for Welding Rods, Electrodes,
and Filler Metals. There are thirty-three welding specifications in
the 2010 Edition of Section II, Part C; they are all identical to their
AWS counterparts.
From 1971 to 1991, Section II consisted of three separate books,
but in 1992, a fourth book was added: Part D, Properties. The publication of Part D was intended to insure that for the ASME B&PV
Code all maximum allowable stress values (and design stress intensity values) based on the same criteria would be identical regardless
of to which of the Construction Codes they applied. Before Part D
was published, Section II had the responsibility for establishing the
allowable stress values, but it was the prerogative of the individual
Construction Codes to accept or reject those values. This led to confusion on the part of ASME B&PV Code users when they found
that the allowable stress values for a particular material could be
different for different Construction Codes, even when the basis for
setting those values was the same. To avoid this kind of inconsistency, the Main Committee of the ASME B&PV Code assigned to
Section II the sole responsibility for assigning Maximum Allowable
Stress Values (and Design Stress Intensity Values).
As of the publication of Section II, Part D in 1992, all allowable
stress values determined based on identical criteria are the same
regardless of the Construction Code involved.
Section II of the 1992 Edition, which included Parts A, B, C
and D cost $1080, the Books respectively cost $325, $300, $270,
and $185; the entire set of Code Books cost $4,753 and this price
included the Code Cases and Interpretations.
The most recent innovation (championed by Section VIII),
which required a great deal of input from and effort by Section II, was the reduction of the material division factor from 4
to 3.5. This was accomplished initially for Sections I and VIII,
Division 1, respectively, through Code Cases 2284 and 2290,
both of which were approved in June 1998. The maximum allowable stress values were included in Tables 1A and 1B of
Section II, Part D in the 1999 Addenda. The reduction in the
material division factor simply considered the technological
advancements [11] that had occurred over the 45 years since
1942, when through a Code Case the value was reduced from
5 to 4 as a material-conservation measure. At the end of World
War II, the material division factor was restored to 5. However,
it was quickly recognized that components built to the division
factor of 4 had provided excellent service and that there was
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-7
considerable service experience with pressure vessels built to
the joint API–ASME Code. Based on that experience, it was decided that a reduction in the material division factor to 4 would
not affect the safety of pressure components built to the ASME
B&PV Code; hence the value was changed back to 4 in the 1950
edition of Section VIII.
In the last 40 years, the stature of the ASME B&PV Code has continued to grow worldwide. There was a concentrated effort by the
ASME Codes and Standards to make the B&PV Code more easily
adoptable internationally. Since the 1914 Edition, generally only
ASTM Specifications have been permitted for Code construction.
This was particularly true since 1945, when all materials for Code
construction had to be based on ASTM Specifications. It became
evident that the requirement for using only ASTM materials for
Code construction was a deterrent to the international acceptance
of the ASME B&PV Code. In 1992, the ASME Board on Pressure
Technology Codes and Standards endorsed the use of non-ASTM
materials for boilers and pressure vessels. Section II was permitted to review recognized international specifications, assess their
possibility of being accepted for Code construction, and provide
allowable stress values based on the procedures and practices used
for ASTM materials [12]. The first of the non-ASTM materials, the
Canadian specification CSA G-40.21 (Specifications for Structural
Quality Steels), was published as SA/CSA-40.21 in the 1998 edition of Section II, Part A.
Section II of the 2001 Edition, which includes Parts A, B, C
and D costs $1,595, the Books respectively cost $410, $395, $395
and $395; the entire set of Code Books cost $7,900, and this price
includes the Code Cases and Interpretations.
The 2004 Edition of the ASME Boiler and Pressure Code was
released near the end of October 2004. A new volume, Section II Part
D—Metric, was included in the 2004 Edition of the B&PVC. Section
II is now comprised of five separate parts, Part A—Ferrous Material
Specifications, Part B—Nonferrous Material Specifications, Part
C Specifications for Welding Rods, Electrodes, and Filler Metals,
Part D Properties (Customary) and Part D (Metric). ASME Codes
and Standards decided that the metric version of Section II Part D
would facilitate the use of the Boiler and Pressure Vessel Code by
organizations that commonly use the metric system in their design
and fabrication of pressure related components. The specifications
provided in Parts A and B in the 2004 Edition of the B&PVC
required 2,714 pages; this represents a 77 fold increase in the amount
of data provided for material specifications during the last 80 years;
all five Books that comprised the 2004 Edition of Section II occupy
5085 pages.
Each of the five Section II Books cited cost $510; the cost for
the entire set of Section II Books is $2,550. A complete set of the
2004 Edition of the B&PVC, 30 Books, including the two Code
Case Books, cost $10,900.
3.1.1
REFERENCES
1. Transactions of the ASME, Vol. 36, pp. 977–1086, 1914.
2. Greene, A. M. Jr., History of the Boiler Code, The American Society
of Mechanical Engineers, New York, 1955.
3. ASTM Standard Specification A-20, General Requirements for
Delivery of Rolled Steel Plates of Flange and Firebox Qualities,
Annual Book of ASTM Standards, The American Society for Testing
Materials, 1965.
4. Cross, W., The Code: An Authorized History of the ASME Boiler and
Pressure Vessel Code, The American Society of Mechanical Engineers, New York, p. 115, 1990.
5. Cross, W., The Code: An Authorized History of the ASME Boiler
and Pressure Vessel Code, The American Society of Mechanical
Engineers, New York, p. 218, 1990.
6. ASME Power Boilers, The American Society of Mechanical Engineers, New York, 1943 ed.
7. ASTM Symposium on the Effect of Temperature on the Brittle
Behavior of Metals with Particular Reference to Low Temperatures,
56th Annual Meeting, The American Society for Testing Material,
Atlantic City, NJ, June 28–30, 1953.
8. Resumé of Investigations on Steels for High Temperature, High
Pressure Applications 1963–1965, The Timken Roller-Bearing Company (Steel and Tube Division), Canton, OH.
9. Bodine, G. C. et al., A Program for the Development of Advanced
Ferritic Alloys for LMFBR Structural Application, Topical Report,
Combustion Engineering, Inc., Windsor, CT, Sept. 1977.
10. Cunningham, G. W. et al., Ferritic Steels as Alternate Structural
Materials for High Temperature Applications (proceedings of an
ASM international conference, Ferritic Steels for High Temperature
Applications), A. K. Khare (ed.), The American Society for Metals,
Metals Park, OH.
11. Canonico, D. A., Adjusting the Boiler Code, Mechanical Engineering,
Vol. 122, No. 2, pp. 54–57.
12. ASME Boiler and Pressure Vessel Code Section II, Part A, Preface,
Ferrous Material Specifications, The American Society of Mechanical
Engineers, 1998.
3.2
BASIS FOR ACCEPTANCE OF
MATERIALS FOR CODE
CONSTRUCTION—SECTION II,
PART A: FERROUS MATERIAL
SPECIFICATIONS
3.2.1
Introduction
It is the policy of the ASME Boiler and Pressure Vessel Committee
to adopt for inclusion in Section II of the ASME Boiler and Pressure
Vessel Code only the specifications that have been adopted by the
American Society for Testing and Materials (ASTM), the American
Welding Society (AWS) (for Section II, Part C), and by other
recognized national or international organizations. The ASME
material specifications are based on those published by ASTM, AWS,
or other recognized national or international organizations. Material
produced to an acceptable material specification is not limited as to
country of origin.
In 1992, the BPTCS endorsed the use of non-ASTM materials
for boiler and pressure vessel applications. The Code follows the
procedures and practices currently in use for ASTM materials to
implement the adoption of non-ASTM Material Specifications.
Not all materials listed in Section II, Part A have been
adopted for Code use. Usage is limited only to those materials
and grades adopted by at least one of the other Code sections for
application under the rules of that section. Materials covered by
these specifications are acceptable for use in items covered by
the Code sections only to the degree indicated in the applicable
section.
All materials accepted by the various Code sections and used
for construction within the scope of their rules must be furnished
in accordance with the material specifications contained in Section II, Parts A, or B, or C, or referenced in the Guidelines on the
Acceptable ASTM Editions of Part A, except where otherwise
3-8 t Chapter 3
provided in ASME Code Cases or in the applicable section of
the Code.
3.2.2
Organization of Section II, Part A
ASME Section II, Part A contains ferrous material specifications
adopted by the ASME for construction of boiler, pressure vessel,
and nuclear power plant components. The ASME material specifications in Section II, Part A, are arranged in numerical sequence
starting with SA-6/SA-6M and ending with the international Material Specifications adopted by ASME, Part A also contains the
following:
(1) Guideline on Submittal of Technical Inquiries to the Boiler
and Pressure Vessel Code.
(2) Specification Removal.
(3) Guideline on the Approval of New Materials Under the ASME
Boiler and Pressure Vessel Code.
(4) Guidelines on Acceptable ASTM Editions.
(5) Guidelines on Acceptable Non-ASTM Editions.
(6) Guidelines on Multiple Marking of Materials.
(7) Summary of Changes.
(8) List of Changes in Record Number Order.
3.2.3
Material Specifications Included
in Section II, Part A
The ASME specifications are listed in two separate indices
in Section II, Part A. One (Specifications Listed in Numerical
Sequence) lists all the Material Specifications in Part A in their
numerical sequence; the other (Product Specifications Listed by
Materials) lists the applicable specifications in numerical sequence
under the various product forms or methods. The product forms
are as follows:
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
pipes;
tubes;
flanges, fittings, valves, and parts;
plates, sheets, and strips for pressure vessels;
bars;
bolting materials;
billets and forgings; and
castings.
Under Specifications Listed by Materials, there are also special
material groupings as follows:
(1) Structural steel;
(2) Corrosion-resisting and heat-resisting steels; and
(3) Wrought iron, cast iron, and malleable iron.
Most ASME material specifications in Section II, Part A have
been adopted from ASTM standards. Changes in the Code policy
made it possible to also adapt material specifications from other
national or international standards. The ASME material specifications can be recognized by letters “S” or “SA”, which have been
added to the adopted material specifications. The letter S appears in
front of the adopted ASTM material specification numbers (SA-20/
SA-20M, SA-516/SA-516M, SA-568, SF-568, etc.), whereas SA
appears in front of other adopted national or international specification numbers (SA/CSA-G40.21, SA/EN-10028-1, etc.) to distinguish the ASME specifications from other specifications (A
516/A 516M, F 568, CSA-G40.21, EN 10028-1, etc.). An ASME
material specification also states whether the ASME specification is
identical to the adopted standard specification, and if not, lists any
additions and exceptions to that specification, and lists the date of
the adopted specification as published in the ASTM or in another
national or international standard.
However, Section II, Part A includes only the ASME cover sheets
for adopted (non-ASTM) national or international specifications
for which the ASME has not been given permission by the
originating organization to publish as material specifications. These
ASME cover sheets list the national or international specification
adopted by ASME, the issue dates of the adopted specifications,
the additional ASME requirements, and the source for obtaining
copies of the referenced national or international specifications
and other documents referenced in the specifications. Users should
obtain their own copies of the non-ASTM national or international
specifications listed in the cover sheet, as well as any other
referenced specifications in the adopted specification.
Some of the material specifications in Section II, Part A include
general requirements specifications. These specifications cover a
group of common requirements that, unless otherwise specified in
the individual material specification, apply to all material specifications for that product form. For example, SA-516/SA-516M references SA-20/SA-20M (Specification for General Requirements
for Steel Plates for Pressure Vessels) for manufacturing, chemical analysis, and several other requirements. Some other specifications include requirements for test methods or nondestructive
examination. An example of a test-methods specification is SA-370
(Standard Test Methods and Definitions for Mechanical Testing
of Steel Products); an example of a nondestructive-examination
specification is SA-578/SA-578M (Specification for StraightBeam Ultrasonic Examination of Plain and Clad Steel Plates for
Special Applications).
The following are typical examples of ASME material specifications published in Section II, Part A, showing only the first page
of the specification.
SA-516/SA-516M This specification is identical with ASTM
specification A 516/A 516M-06. (See Fig. 3.2.1.)
SA-240/SA-240M This specification is identical to ASTM
specification A 240/A 240M-04. (See Fig. 3.2.2.)
SA/EN 10028-2 This specification is identical with BS EN
10028-2-2009 with the additional requirements listed on the
ASME cover sheet. (See Fig. 3.2.3.) No other edition is approved
for ASME use.
3.2.4
Guidelines for Approval and Use of the
Materials for ASME Code Construction
Section II, Part A includes the following general guidelines for
approval and use of materials for ASME Code construction:
(1) Submittal of Technical Inquiries to the Boiler and Pressure
Vessel Committee.
(2) Acceptable ASTM and Non-ASTM Editions.
(3) Guidelines on Multiple Marking of Materials.
(4) Approval of New Materials Under the ASME Boiler and
Pressure Vessel Code.
The following is a brief summary of the provisions in two of
these guidelines. The Guideline on the Approval of New Materials
Under the ASME Boiler and Pressure Vessel Code is discussed in
paragraph 3.2.5.
3.2.4.1 Acceptable ASTM and Non-ASTM Editions All
materials originating from an ASTM specification, allowed
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-9
SPECIFICATION FOR PRESSURE VESSEL PLATES,
CARBON STEEL, FOR MODERATE- AND LOWERTEMPERATURE SERVICE
SA-516/SA-516M
(Identical with ASTM Specification A 516/A 516M-06)
1.
Scope
1.1 This specification covers carbon steel plates
intended primarily for service in welded pressure vessels
where improved notch toughness is important.
1.2 Plates under this specification are available in four
grades having different strength levels as follows:
Grade U.S. [SI]
55
60
65
70
[380]
[415]
[450]
[485]
Tensile Strength,
ksi [MPa]
55–75
60–80
65–85
70–90
[380–515]
[415–550]
[450–585]
[485–620]
1.3 The maximum thickness of plates is limited only
by the capacity of the composition to meet the specified
mechanical property requirements; however, current practice normally limits the maximum thickness of plates furnished under this specification as follows:
Grade U.S. [SI]
55
60
65
70
[380]
[415]
[450]
[485]
Maximum Thickness,
in. [mm]
12
8
8
8
[305]
[205]
[205]
[205]
1.4 For plates produced from coil and furnished without
heat treatment or with stress relieving only, the additional
requirements, including additional testing requirements
and the reporting of additional test results of Specification
A 20/A 20M apply.
1.5 The values stated in either inch-pound units or SI
units are to be regarded separately as standard. Within the
text, the SI units are shown in brackets. The values stated
in each system are not exact equivalents; therefore, each
system must be used independently of the other. Combining
values from the two systems may result in nonconformance
with the specification.
2.
Referenced Documents
2.1 ASTM Standards:
A 20/A 20M Specification for General Requirements for
Steel Plates for Pressure Vessels
A 435/A 435M Specification for Straight-Beam Ultrasonic
Examination of Steel Plates
A 577/A 577M Specification for Ultrasonic Angle-Beam
Examination of Steel Plates
A 578/A 578M Specification for Straight-Beam Ultrasonic
Examination of Plain and Clad Steel Plates for Special
Applications
3.
General Requirements and Ordering
Information
3.1 Plates supplied to this product specification shall
conform to Specification A 20/A 20M, which outlines the
testing and retesting methods and procedures, permissible
variations in dimensions and mass, quality and repair of
defects, marking, loading, and so forth.
3.2 Specification A 20/A 20M also establishes the rules
for ordering information that should be complied with when
purchasing plates to this specification.
3.3 In addition to the basic requirements of this specification, certain supplementary requirements are available
where additional control, testing, or examination is
required to meet end use requirements.
3.4 The purchaser is referred to the listed supplementary requirements in this specification and to the detailed
requirements in Specification A 20/A 20M.
FIG. 3.2.1 SPECIFICATION FOR PRESSURE VESSEL PLATES, CARBON STEEL, FOR MODERATE- AND LOWERTEMPERATURE SERVICE-FIRST PAGE ONLY (Source: Section II, Part A of the 2015 ASME B&PV Code)
3-10 t Chapter 3
SPECIFICATION FOR CHROMIUM AND CHROMIUMNICKEL STAINLESS STEEL PLATE, SHEET, AND STRIP
FOR PRESSURE VESSELS AND FOR
GENERAL APPLICATIONS
SA-240/SA-240M
(Identical with ASTM Specification A 240/A 240M-13c)
1.
Scope
1.1 This specification covers chromium, chromiumnickel, and chromium-manganese-nickel stainless steel
plate, sheet, and strip for pressure vessels and for general
applications.
3.
General Requirements
3.1 The following requirements for orders for material
furnished under this specification shall conform to the
applicable requirements of the current edition of Specification A 480/A 480M.
1.2 The values stated in either inch-pound units or SI
units are to be regarded separately as standard. The values
stated in each system are not exact equivalents; therefore,
each system must be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.
3.1.1 Definitions,
1.3 This specification is expressed in both inch-pound
and SI units. However, unless the order specifies the applicable “M” specification designation (SI units), the material
shall be furnished in inch-pound units.
3.1.6 Heat treatment,
3.1.2 General requirements for delivery,
3.1.3 Ordering information,
3.1.4 Process,
3.1.5 Special tests,
3.1.7 Dimensions and permissible variations,
3.1.8 Workmanship, finish and appearance,
3.1.9 Number of tests/test methods,
3.1.10 Specimen preparation,
2.
Referenced Documents
2.1 ASTM Standards:
A 370 Test Methods and Definitions for Mechanical Testing of Steel Products
A 480/A 480M Specification for General Requirements for
Flat-Rolled Stainless and Heat-Resisting Steel Plate,
Sheet, and Strip
A 923 Test Methods for Detecting Detrimental Intermetallic Phase in Wrought Duplex Austenitic/Ferritic Stainless Steels
E 112 Test Methods for Determining Average Grain Size
E 527 Practice for Numbering Metals and Alloys (UNS)
2.2 SAE Standard:
J 1086 Practice for Numbering Metals and Alloys (UNS)
3.1.11 Retreatment,
3.1.12 Inspection,
3.1.13 Rejection and rehearing,
3.1.14 Material test report,
3.1.15 Certification, and
3.1.16 Packaging, marking, and loading.
4.
Chemical Composition
4.1 The steel shall conform to the requirements as
to chemical composition specified in Table 1, and shall
conform to applicable requirements specified in Specification A 480/A 480M.
FIG. 3.2.2 SPECIFICATION FOR HEAT RESISTING CHROMIUM AND CHROMIUM NICKEL STAINLESS STEEL PLATE,
SHEET, AND STRIP FOR PRESSURE VESSELS (Source: Section II, Part A of the 2015 ASME B&PV Code)
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-11
SPECIFICATION FOR FLAT PRODUCTS MADE OF
STEELS FOR PRESSURE PURPOSES
Part 2: Non-Alloy and Alloy Steels With Specified
Elevated Temperature Properties
SA/EN 10028-2
(Identical with EN 10028-2:2009, with the additional requirements listed on this cover sheet.)
1.
Additional Requirements
1.1 Marking
In addition to the marking requirements of this specification, all products required to be marked and material identification used on all documentation required by this
specification are to be identified by this SA/EN specification designation.
Plates that have been given the full heat treatment
required by para. 8.2.1 or 8.2.2 shall be marked by the
party performing the heat treatment with the letters designating the applicable heat treatment condition in Table 3 of
EN 10028-2 following the stamped steel name or number.
Plates that are not heat treated but are qualified on the
basis of heat treated specimens per para. 8.2.3 shall be
stamped with letter “G” following the stamped specification designation.
1.2 Tension Tests
For quenched and tempered plates one tension test shall
be taken from each end of the heat treated plate. The gage
length of the tension test specimens shall be taken at least
1T from any heat treated edge, where T is the thickness
of the plate, and shall be at least 1⁄2 in. (12.5 mm) from
flame cut or heat-affected-zone surfaces.
1.3 Quality
All surface imperfections, the removal of which will
reduce the plate thickness below its permissible minimum,
shall be cause for rejection of the plate; however by
agreement with the purchaser, the metal so removed may
be replaced with weld metal.
Preparation for repair welding shall include inspection
to assure complete removal of the defect.
Repairs shall be made utilizing welding procedures qualified in accordance with ASME Section IX and repair
welding shall be done by welders or welding operators
meeting the qualification requirements of ASME
Section IX.
2.
National Parts
2.1 The National Foreword and the National Annexes,
if any, do not apply for SA/EN 10028-2.
3.
Source
3.1 See Nonmandatory Appendix A for ordering information to obtain an English language copy of EN 10028-2
and its references.
FIG. 3.2.3 SPECIFICATION FOR FLAT PRODUCTS MADE OF STEELS FOR PRESSURE PURPOSES (Source: Section II, Part A
of the 2015 ASME B&PV Code)
by the various Code Sections and used for construction within
the scope of their rules shall be furnished in accordance with
the material specifications contained within Section II and this
guideline except where otherwise provided in Code Cases or in
the applicable Section of the Code. Materials covered by these
specifications are acceptable for use in items covered by the Code
Sections only to the degree indicated in the applicable Section.
Materials for Code use should preferably be ordered, produced,
and documented on this basis; however, material produced under
an ASTM Specification listed in Table II-200-1 may be used in lieu
of the corresponding ASME Specification listed in this guideline,
provided any additional requirements referenced in the subtitle are
met. Table II-200-1 lists the latest adopted ASTM Specifications
and the issue dates of other acceptable ASTM editions, as well as
the Codebook sections of the Boiler and Pressure Vessel Code in
which a particular specification is approved for use.
Material produced to an ASME or ASTM specification with
requirements different from the requirements of the corresponding specification may also be used in accordance with the above,
provided the material manufacturer or vessel manufacturer certifies with evidence acceptable to the Authorized Inspector that
the corresponding Specification requirements have been met.
This guideline lists the Specifications, originating from ASTM,
and their acceptable dates of issue as well as the Book sections
of the ASME Boiler Code in which the specification is approved
for use.
3-12 t Chapter 3
All materials originating from a non-ASTM specification, allowed by the various Code Sections and used for construction
within the scope of their rules shall be furnished in accordance
with the material specifications contained within Section II and
this guideline except where otherwise provided in Code Cases or
in the applicable Section of the Code. Materials covered by these
specifications are acceptable for use in items covered by the Code
Sections only to the degree indicated in the applicable Section.
Materials for Code use should preferably be ordered, produced,
and documented on this basis; however, material produced under
a non-ASTM specification listed in Table II-200-2 may be used
in lieu of the corresponding ASME specification as listed in this
Appendix. Material produced to an ASME or non-ASTM specification with requirements different from the requirements of the corresponding Specification may also be used in accordance with the
above, provided the material manufacturer or vessel manufacturer
certifies with evidence acceptable to the Authorized Inspector that
the corresponding Specification requirements have been met. This
guideline lists the non-ASTM specifications, originating not from
ASTM, and their acceptable dates of issue as well as the Book
sections of the ASME boiler Code in which the specification is
approved for use.
3.2.4.2 Guidelines on Multiple Marking of Materials Many
Material Specifications or grades have significant overlap of
chemical composition ranges or mechanical properties. It is
common for Material Manufacturers to produce materials that
meet the requirements of more than one specification, grade,
class, or type. Some examples are SA-516 Gr. 65 and Gr. 70,
SA-53 and SA-106, and SA-240 Type 304 and Type 304L, and
so forth.
Dual marking on materials is acceptable, as long as the material
so marked meets all of the requirements of all of the specifications,
grades, classes, and types with which it is marked. (See II-A Mandatory Appendix III.) All of the attributes of the multiply-marked
grades of specifications must overlap (e.g. chemical composition,
mechanical properties, dimensions and tolerances). The material
so marked must also exhibit values that all fall within the limitations of the overlaps, and the controlled attributes of the specification or grades must overlap (e.g. melting practices, heat treatments,
and inspection requirements).
Grade substitution is not permitted. For example, material that
meets all of the composition limits for SA-240 Type 304, contains 0.06% C and 0.02% N, but also contains 0.45% Ti. This
material cannot be marked or supplied as meeting SA-240, Type
304 because the Ti content meets the requirements of SA-240,
Type 321—that is, Ti must be at least 5 × (C + N) but not more
than 0.7%.
3.2.5
Guideline on the Approval of New Materials
Under the ASME Boiler and Pressure
Vessel Code
Each Part of Section II includes a guideline on the approval of
new materials for use in ASME Boiler and Pressure Vessel Code
construction. The Inquirer must furnish to the Code Committee
the appropriate Material Specification and the data specified in
the guideline to enable the Committee to evaluate the material and
to assign design stress values over the range of temperatures for
which the material is to be used. The following is a brief summary of the guideline in Part A of Section II. Readers should
familiarize themselves with all the provisions of the guidelines in
Section II, Parts A and D, before submitting requests to the Code
Committee for approval of new materials. However, the material
cannot be used in Code construction until adopted by one of the
Codebook sections (such as Section I, VIII, Division 1 and Division 2, etc.).
3.2.5.1 Code Policy This guideline, Mandatory Appendix IV in
Section II, Part A, (also Appendix 5 in Section II, Part D) outlines
the Code requirements for approval of new materials. It is the
policy of the ASME Boiler and Pressure Vessel Code to adopt
for inclusion in Section II only those specifications which have
been adopted by the ASTM, by the AWS, and by other recognized national or international organizations. For materials made
to a recognized national or international specification other than
ASTM or AWS, the inquirer must notify the standards-developing
organization that a request has been made to ASME for adoption
of their specification under the ASME Boiler and Pressure Vessel
Code. In addition, the inquirer must request that the organization
grant ASME permission to reprint the specification. This action
does not prohibit requests for Code approval of other materials; in
such cases the inquirer shall make a request to ASTM, AWS, or
other appropriate national or international organization to develop
a specification that can be presented to the Code Committee.
It is a policy of the Code Committee to consider requests to adopt
new materials only from boiler, pressure-vessel, or nuclear-powerplant-component manufacturers or end users. Furthermore, such
requests should be for materials for which a reasonable expectation
exists for use in a boiler, pressure vessel, or nuclear power plant
component constructed to the rules of one Codebook Sections. All
requests for adoption of new materials shall include the following information:
3.2.5.2 Application The inquirer shall identify the following:
(1) the section or sections and divisions of the Code in which
the new material is to be incorporated;
(2) the temperature range of the application;
(3) whether cyclic service is to be considered;
(4) whether external pressure is to be considered; and
(5) all product forms, size ranges, and specifications for which
incorporation is desired.
3.2.5.3 Mechanical Properties The inquirer shall furnish the
following data on which to base the design values for inclusion in
the applicable in the Code tables:
(1) The appropriate Material Specification.
(2) Ultimate tensile strength, yield strength, reduction of area,
and elongation, at 100oF (or 50oC) intervals, from room
temperature to 100oF (50oC) above the maximum-use
temperature, unless the maximum use-temperature does not
exceed 100oF (50oC).
(3) If the desired maximum use-temperature involves timedependent behavior, stress-rupture data and creep-rupturestrength data of the base metal and appropriate weld metals
and weldments at 100oF (50oC) intervals to 100oF (50oC)
above the intended maximum-use temperature.
(4) Notch toughness data for all materials for which Code toughness rules would be expected to apply, including test results
for the intended lowest service metal temperature and for the
range of desired material thickness. For welded construction, the notch-toughness data shall include the results of
Code-toughness tests for weldments and heat-affected zones
for weldments made by the intended welding processes.
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-13
(5) Stress-strain curves (tension or compression) for material
in components that operate under external pressure,
at 100oF (50oC) intervals over the range of desired
design temperatures.
(6) Fatigue data, if the material is to be used in cyclic service
and if the Construction Code requires explicit consideration
of cyclic behavior.
In general, for all mechanical properties, the data shall be
furnished from at least three heats of material—meeting all
requirements of the specification for at least one product form for
which adoption is desired—for each test at each test temperature.
For product forms for which the properties may be size-dependent,
data from products of different sizes, including the largest size for
which adoption is desired, shall be provided.
3.2.5.4 Other Properties The inquirer shall furnish to the
Committee adequate data necessary to establish values for the
following properties over the range of temperatures for which
the material is to be used when the applicable Construction Code
requires explicit consideration:
(1)
(2)
(3)
(4)
(5)
(6)
Young’s modulus;
density;
Poisson’s ratio;
coefficient of thermal expansion;
thermal conductivity; and
thermal diffusivity.
3.2.5.5 Weldability The inquirer shall furnish complete data
on the weldability of the material intended for welding, including
data on procedure qualification tests made in accordance with
the requirements of Section IX. Welding tests shall be made
over the full range of thickness in which the material will be
used. The inquirer shall provide pertinent information such as
the following:
(1) postweld heat treatment required;
(2) susceptibility to air hardening;
(3) the effect of welding procedure on heat-affected zone and
weld metal notch toughness; and
(4) the amount of experience in welding the material.
3.2.5.6 Physical Changes The inquirer shall also inform the
Committee on the influence of conditions known to the inquirer
that could cause significant changes in the mechanical properties,
microstructure, resistance to brittle fracture, and so on, during
manufacture or service, such as the following:
(1) fabrication practices (e.g., forming, welding, thermal treatments, including cooling rates, and combinations of
mechanical working and heat treatments).
(2) exposure to certain service environments, including
temperature ranges of exposure.
The inquirer may refer to known properties or known conditions
of ASME-approved, like materials in his request for Code approval
of a particular material. The Code Committees will evaluate the
data and will indicate approval and any additions or exceptions
applicable to the specification published in the national or international standard and adopted by the ASME.
3.2.5.7 ASME Code Cases The Code Committee will consider
the issuance of an ASME Code Case—permitting the use of a new
material—if the following conditions are met:
(1) The inquirer provides evidence that the material is made to
an ASTM Specification or a recognized national or international standard.
(2) The material is commercially available and can be
purchased to the proposed specification requirements.
(3) The inquirer shows that a reasonable demand of the material exists in the industry and that there exists an urgency for
approval by means of a Code Case.
(4) The request for approval of the material shall clearly describe it in specification form (i.e., the scope, process, manufacture, delivery conditions, heat treatment, chemical and
tensile property requirements, testing requirements, forming properties, workmanship, finish, marking, inspection
and rejection).
(5) The inquirer furnishes all the data specified in the “Guideline on the Approval of New Materials under the ASME
Boiler and Pressure Vessel Code”.
(6) All other requirements identified in Section II under “Code
Policy” and “Application” have been met.
3.2.6
References
1. ASME Boiler and Pressure Vessel Code, Section II, Part A, The
American Society of Mechanical Engineers, 2015 edition.
2. Moen, Richard A., CASTI Guidebook to ASME Section II, B31.1 &
B31.3 (Materials Index), 2008.
3.3
BASIS FOR ACCEPTANCE OF
MATERIALS FOR CODE
CONSTRUCTION—SECTION II,
PART B: NONFERROUS MATERIAL
SPECIFICATIONS
3.3.1
Introduction
ASME Section II, Part B includes nonferrous Material Specifications adopted by the ASME for construction of boiler, pressurevessel, and nuclear-power-plant components. These specifications
are identical with or similar to the specifications published by the
ASTM, AWS and other recognized national or international organizations. It is the policy of the ASME B&PV Committee to adopt
for inclusion in Section II only those specifications that have been
adopted by the ASTM, the AWS (for Section II, Part C [1]), and by
other recognized national and international organizations. Material
produced to an acceptable Material Specification is not limited to
its country of origin.
In 1992, the BPTCS endorsed the use of non-ASTM materials
for boiler and pressure vessel applications. The Code follows the
procedures and practices currently in use for ASTM materials to
implement the adoption of non-ASTM Material Specifications.
Not all materials listed in Material Specifications in Section II,
Part B [2] have been adopted for Code use. Usage is limited to
only those materials and grades adopted by at least one of the Code
sections for application under the rules of that section. Materials
covered by these specifications are acceptable for use in items
covered by the Code sections only to the extent indicated in the
applicable section. In Tables 1B, 2B, and 5B, allowable stresses
are provided for Sections, I, III, IV, VIII-1, VIII-2, and XII, to
the extent indicated therein. The maximum temperature of use is
also indicated. The abbreviation for “not permitted” (NP) is shown
where a Codebook section does not allow this material to be used.
3-14 t Chapter 3
In general, an alloy is usually not permitted either because it has
not been requested for use or it is for some specific reason not
applicable to that section.
All materials allowed by the various Code sections and used for
construction within the scope of their rules must be furnished in
accordance with the Material Specifications contained in Section
II, Part B, or referenced in Appendix A of Part B, except where
otherwise provided in the Code Cases or in the applicable Code
section. It is important to visit the tables listing the acceptable
specifications and alloys in some of the Code sections. For example, Tables UNF 23.1, 23.2, 23.3, 23.4 and 23.5 list the acceptable
alloys for each nonferrous SB specification in Section VIII Div-1.
3.3.1.1 Alloy Definitions In Section II, Part B, it is easy to call
the alloys nonferrous when they are titanium, copper, zirconium
or even nickel-based alloys. However, many alloys listed in B/
SB specifications for nickel alloys are (if developed today) ferrous alloys. These materials all have the unified numbering system
(UNS) [3] alloy identification as N08xxx. The old rule was to
consider an alloy to be ferrous if more than 50% of its composition
was of elements other than iron. For all new materials of the present
day, however, the largest element content dictates the specification
with which the alloy is to be used. If an alloy has more than 50%
of its content other than iron but with iron still its largest single
component, it would then be a ferrous material. Alloys of the UNS
N08xxx type are currently added to ferrous Material Specifications
while simultaneously remaining in the nonferrous ones.
3.3.2
Organization of Section II, Part B
ASME Section II, Part B contains nonferrous material specifications in their numerical sequence, starting with SB-26/SB-26M aluminum specification, and ending with an international specification
SB/EN 1706 adopted by the ASME. As international specifications
are included, they will only include the ASME cover sheet for the
ASME-adopted national and international specifications for which
the ASME has not been given permission to publish in their entirety.
Section II, Part B also contains the following:
(1) Statement of Policy on the Use of the Certification Mark
and Code Authorization in Advertising
(2) Statement of Policy on the Use of ASME Marking to Identify Manufactured Items
(3) Submittal of Technical Inquiries to the Boiler and Pressure
Vessel Committee—Mandatory
(4) Specifications Listed by Materials
(5) Specification Removal
(6) Summary of Changes
(7) List of Changes in Record Number Order
3.3.3
Material Specifications Included in Section II,
Part B
The ASME Material Specifications are listed in three separate
indices in Section II, Part B. The first (Specifications listed by
Materials), given here as Table 3.3.1, is a listing of the ASME nonferrous Material Specifications by element class, product forms,
and specification test methods as follows:
(1) aluminum and aluminum alloys;
(2) copper alloy castings;
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
(15)
cobalt alloys;
copper and copper alloy pipe and tubes;
copper and copper alloy plate, sheet, strip, and rolled bar;
copper and copper alloy rod, bar and shapes;
copper test methods;
nickel alloy castings;
nickel and nickel alloy fittings;
nickel and nickel alloy pipe and tubes;
nickel and nickel alloy plate, sheet, and strip;
nickel and nickel alloy rod, bar, and wire;
Other;
titanium and titanium alloys; and
zirconium and zirconium alloys.
The second of these indices shown in Mandatory Appendix II
(Basis for use of acceptable ASME and ASTM editions, Table II200-1) lists all of the nonferrous Material Specifications in Section II, Part B in their numerical sequence. A third indice (Basis
for use of acceptable non-ASME editions, Table II-200-2) lists the
Material Specification originating for non-ASTM specifications
allowed by the various Code Sections and used for construction
within the scope of their rules.
The ASME Material Specification in Section II, Part B add
letters “S” or “SB” to the designations in the ASME-adopted
national or international Material Specifications (e.g., B75) to
distinguish them from the national or international specifications
(e.g., B-75). The subtitle (or preamble) of the ASME Specification lists any additions and exceptions to the specifications published in the national or international standards and adopted by
the ASME, including the edition date of the specification published in the national or international standard and adopted by the
ASME. In nonferrous materials, the most common addition to the
corresponding ASTM Specification is to make certification and
test reports mandatory.
National or international specifications adopted by the ASME
for which it had not been given permission by the originating
organization to publish are referenced on the cover sheets of
these specifications near the end of Section II, Part B. These
cover sheets list only the additional ASME requirements and the
source for obtaining copies of the referenced national or international specifications and other documents referenced in the specifications. Users should obtain their own copies of the national
or international specifications listed in the cover sheet for other
requirements in the specifications.
Several Material Specifications in Section II, Part B include
general requirements for particular material-product form combinations, and some others include requirements for test methods
or examination of product forms. An example of a general
requirements specification is SB-906 (General Requirements for
Flat-Rolled Nickel and Nickel Alloys Plate, Sheet, and Strip); an
example of a test method specification is SB-858 (Test Method
Ammonia Vapor Test for Determining Susceptibility to Stress
Corrosion Cracking in Copper Alloys).
SB-363 (Specification for Seamless and Welded Unalloyed
Titanium and Titanium Alloy Welding Fittings), shown at the
end of Table 3.3.1, is a typical example of an ASME Materials
Specification published in Section II, Part B. This specification is
identical to ASTM Specification B363-14, except that certification
and a test report have been made mandatory, and Supplementary
Requirement S5 is mandatory.
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TABLE 3.3.1 SPECIFICATIONS LISTED BY MATERIALS
(Source: Section II, Part B of the 2015 ASME B&PV Code)
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TABLE 3.3.1
SPECIFICATIONS LISTED BY MATERIALS (CONT’D)
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TABLE 3.3.1
SPECIFICATIONS LISTED BY MATERIALS (CONT’D)
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TABLE 3.3.1
SPECIFICATIONS LISTED BY MATERIALS (CONT’D)
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TABLE 3.3.1
SPECIFICATIONS LISTED BY MATERIALS
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3.3.4
Guidelines for Approval and Use of the
Materials for ASME Code Construction
Section II, Part B includes the following general guidelines for
approval and use of materials for ASME Code construction:
(1) Submittal of Technical Inquiries to the Boiler and Pressure
Vessel Committee
(2) Acceptable ASTM editions
(3) Acceptable Non-ASTM editions
(4) Approval of New Materials Under the ASME Boiler and
Pressure Vessel Code
(5) Guidelines on Multiple Marking of Materials
The following is a brief summary of the provisions in these
guidelines. The Guidelines on the Approval of New Materials
under the ASME Boiler and Pressure Vessel Code is discussed in
paragraph 3.3.5.
3.3.4.1 Submittal of Technical Inquiries to the Boiler and
Pressure Vessel Committee This guideline provides information to Code users for submitting technical inquiries to the Code
Committee. See Guidelines on the Approval of New Materials
under the ASME Boiler and Pressure Vessel Code in Section II,
Part C and D for additional requirements for requests involving
adding new materials to the Code. Technical inquiries include
requests for revisions or additions to the Code rules, requests for
Code Cases and/or requests for Code interpretations. This guideline
includes a description of the inquiry format, requests for Code
revision or additions, requests for Code Cases, requests for Code
Interpretations, and how these inquiries should be submitted.
3.3.4.2 Acceptable ASTM and Non-ASTM Editions The
Material Specifications in Section II are acceptable for use in items
covered by a particular Codebook section only to the extent permitted in the applicable Codebook section (e.g. Section I and Section
VIII, Division I). Section II, Part B includes a table that lists ASME
Materials Specifications and the ASME Codebooks sections of the
B&PV Code in which the specification are approved for use. Materials
for the Code use should preferably be ordered, produced, and documented on the basis of the ASME specifications; however, materials
produced under an ASTM Specification listed in Table II-200-1 may
be used in lieu of the corresponding ASME Specification listed in this
guideline. Table II-200-1 lists the latest adopted ASTM Specifications
and the issue dates of other acceptable ASTM editions, as well as the
Codebook sections of the Boiler and Pressure Vessel Code in which
a particular specification is approved for use.
Material produced to an ASME or ASTM Specification with
requirements different from the requirements of the corresponding Specification may also be used in accordance with the above,
provided the material manufacturer or vessel manufacturer certifies with evidence acceptable to the Authorized Inspector that the
corresponding Specification requirements have been met. This
guideline lists the Specifications, originating from ASTM, and
their acceptable dates as well as the Book sections of the ASME
Code in which the specification is approved for use.
All material originating from a non-ASTM Specification, allowed
by the various Code Sections and used for the construction within their
scope of their rules shall be furnished in accordance with the Material Specification contained within Section II and this guideline except
where otherwise permitted in Code Cases or in the applicable Section
of the Code. Materials covered by these Specifications are acceptable for use in terms covered by the Code Sections only to the degree
indicated in the applicable Section. Materials for Code use should be
preferable ordered, produced, and documented on this basis.
Materials produced under a non-ASTM specification listed in Table
II-200-2 may be used in lieu of the corresponding ASME Specification. Material produced to an ASME or non-ASTM Specification with the requirements different from the requirements of the
corresponding Specification may also be used in accordance with
the above, providing the materials manufacturer or vessel manufacturer certifies with evidence acceptable to the Authorized Inspector
that the corresponding Specification requirements have been met.
This guideline lists the non-ASTM Specifications, originating
not from ASTM, and their acceptable dates of issue as well as the
Book sections of the ASME Boiler Code in which the specification
is approved for use.
3.3.4.3 Guidelines on Multiple Marking of Materials The
principal for Section II, Part B is identical to that for Section II,
Part A [5], although in reality not need currently exists for the
multiple marking of nonferrous materials.
3.3.4.4 Appendices Section II, Part B includes the following
appendices that are pertinent to Material Specifications:
Mandatory Appendix I - Standard Units for Use in Equations
Non-mandatory Appendix A - Sources of Standards
3.3.5
Guideline on the Approval of New Materials
Under the ASME Boiler and Pressure
Vessel Code
This guideline in Section II, Part B (also, Appendix 5 in Section II,
Part D [6]) outlines the Code requirements for approval of new materials. Normally, requests for Code approval of new materials should
be made for materials that have a recognized national or international
specification. This does not prohibit requests for Code approval of
other materials, but in such cases the inquirer should make a request
to the appropriate recognized national or international organization to
develop a specification that can be presented to the Code Committee.
It is the policy of the B&PV Committee to consider requests for
the adoption of new materials only from boiler, pressure-vessel,
and nuclear-power-plant-component manufacturers or end users.
Furthermore, such requests should be for materials for which a reasonable expectation exists for use in a boiler, pressure-vessel, or
nuclear-power-plant component constructed to the rules of one of
the Codebook sections. All requests for adoption of new material
shall include the following information:
3.3.5.1 Application The inquirer shall identify the following:
(1) the section or sections and divisions of the Code in which
the new material is to be incorporated;
(2) the temperature range of the application;
(3) whether cyclic service is to be considered;
(4) whether external pressure is to be considered; and
(5) all product forms, size ranges, and specifications for which
incorporation is desired.
3.3.5.2 Mechanical Properties The inquirer shall furnish the
following data on which to base the design values for inclusion in
the applicable Code tables.
(1) The appropriate Material Specification.
(2) Ultimate tensile strength, yield strength, reduction of
area, and elongation at 100°F (50°C) intervals from room
3-26 t Chapter 3
(3)
(4)
(5)
(6)
(7)
temperature to 100°F (50°C) above the maximum-use temperature, unless the maximum-use temperature does not exceed 100°F (50°C). Any heat treatment that is required to
produce the mechanical properties should be fully described.
If the desired maximum-use temperature involves timedependent behavior, the stress rupture and creep-rupturestrength data of the base metal and appropriate weld metals
and weldments at 100°F (50°C) intervals to 100°F (50°C)
above the intended maximum-use temperature. When
creep-rate and creep-rupture-strength data are not included,
the Code analysis will limit the maximum temperature to
one that is known to be significantly lower; one in which
time-independent behavior is the design criterion.
Notch toughness data for all materials for which Codetoughness rules are expected to apply, including test results
for the intended lowest service metal temperature and
for the range of desired material thicknesses. For welded
construction, the notch-toughness data shall include the
results of the Code-toughness tests for weld metal and
heat-affected zones for weldments made by the intended
welding processes.
Stress–strain curves (tension or compression) for material
in components that operate under external pressure at 100°F
(50°C) intervals over the range of desired design temperatures. This data can be presented in digital form.
Fatigue data, if the material is to be used in cyclic service
and if the Construction Code requires explicit consideration
of cyclic behavior.
All other requirements identified in Section II under “Code
Policy” and “Applications” have been met.
In general, for all mechanical properties, the data shall be furnished from at least three heats of material meeting all requirements of the specification for at least one product form for which
adoption is desired—for each test at each test temperature. In
product forms for which the properties may be size-dependent,
data from products of different sizes, including the largest size for
which adoption is desired, shall be provided to prove that the same
or independent trend curves shall be used. If more than three heats
are supplied, the data for at least three must be continuous from
room temperature to the maximum temperature.
3.3.5.3 Other Properties The inquirer shall furnish to the Code
Committee sufficient data to establish values for the following
properties over the range of temperatures for which the material
is to be used and for which the applicable Construction Code
required explicit consideration:
(1)
(2)
(3)
(4)
(5)
(6)
Young’s modulus;
shear modulus;
Poisson’s ratio;
coefficient of thermal expansion;
thermal conductivity; and
thermal diffusivity.
3.3.5.4 Weldability The inquirer shall furnish complete data
on the weldability of the material intended for welding, including
data on procedure qualification tests made in accordance with the
requirements of Section IX [7]. Welding tests shall be made over
the full range of thickness in which the material will be used. The
inquirer shall provide pertinent information such as the following:
(1) postweld heat treatment required;
(2) susceptibility to air hardening;
(3) effect of the welding procedure on the heat-affected zone
and weld-metal notch toughness;
(4) the amount of experience needed in welding the material; and
(5) mechanical properties of the weld metal at elevated temperatures. There are cases where the allowable stress values or
stress intensity values are based on the weld metal properties and not the base metal, because the weld metal values
are significantly lower than the base metal.
If welding information is not included, it might represent the
Code Committee’s conclusion to deem the material suitable for
nonwelded construction only.
3.3.5.5 Physical Changes The inquirer shall also inform the Code
Committee of conditions that could cause significant changes in the
mechanical properties, microstructure, resistance to brittle fracture,
and so on, during manufacturing or service, such as the following:
(1) fabrication practices (e.g., forming, welding, thermal treatments, including cooling ranges, and combinations of
mechanical working and thermal treatments); and
(2) exposure to certain service environments (e.g., particular
temperature ranges of exposure and the exposure to certain
environments).
The inquirer may refer to properties of known conditions of
similar ASME-approved materials in his or her request for Code
approval of a particular material. The Code Committee will evaluate the data, indicate approval, and make any additions or exceptions applicable to the specification published in the national or
international standard and adopted by the ASME.
3.3.5.6 ASME Code Cases The Code Committee will consider
issuing a Code Case—provided the following conditions are met:
(1) The inquirer provides evidence that the material is made to
an ASTM or another recognized national or international
standard.
(2) The material is commercially available and can be purchased to the proposed specification requirements.
(3) The inquirer shows that a reasonable demand of the material
exists in the industry and that an urgency exists for approval
by means of a Code Case.
(4) The request for approval of the material shall clearly
describe the material in specification form (i.e., the scope,
process, manufacture, delivery conditions, heat treatment,
chemical and tensile property requirements, testing requirements, forming properties, workmanship, finish, marking,
inspection, and rejection).
(5) The inquirer furnishes to the Code Committee all the
data specified in the “Guideline on the Approval of
New Materials under the ASME Boiler and Pressure
Vessel Code.”
(6) All other requirements identified in Section II under “Code
Policy” and “Application” have been met.
3.3.6
Interpretations
Users of the ASME B&PV Code may submit written requests
for interpretations to the ASME B&PV Committee regarding the
Code rules. Section II, Part B of the B&PV Code includes written interpretations, issued between the indicated dates, in response
to inquiries concerning the Material Specifications contained in
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Section II, Part B. Each interpretation is identified by the Code
section and the record number.
8. ASME B31.1, Power Piping, The American Society of Mechanical
Engineers, 2014 edition.
3.3.7
9. ASME B31.3, Process Piping, The American Society of Mechanical
Engineers, 2014 edition.
ASME B31.1: Nonferrous Material
Specifications
ASME B31.1 (Power Piping) [8] allows materials that conform to specifications listed in its Table 126.1, given here as
Table 3.3.2. The significant difference to the B&PV Code is the
allowance in B31.1 of a direct ASTM Specification with a note
stating that the corresponding SB specification can be used interchangeably. This allows specifications to be used without testing
and without the need for Material Certifications. The exception
is the requirement for boiler external piping (BEP); here, the
ASME-approved SB version is required. Only when the ASTM
Specification is identical to or as stringent as its ASME counterpart can it be used.
Appendix F, given here as Table 3.3.3, is a list of the latest
approved ASTM editions and other B31.1-approved standard
organization specifications. The allowable stresses for each alloy
to each specification is noted in Appendix A: Table A-4 for nickel
and high nickel alloys, Table A-6 for copper and copper alloys,
Table A-7 for aluminum and aluminum alloys, Table A-8 for
temperatures 1,200°F and above and Table A-9 for titanium and
titanium alloys.
3.3.8
ASME B31.3: Nonferrous Material
Specifications
ASME 31.3 (Process Piping) [9] discusses materials and notes
that materials conforming to listed specifications may be used.
Appendix A contains the allowable stresses and quality factors for
metallic piping and bolting materials in addition to a specification
index, given here as Table 3.3.4, that lists the ASTM designations.
Similar comments made for B31.1 can be made regarding the
quality of the specifications permitted. Unlisted materials may also
be used if they conform to a published specification that covers
chemical, physical, and mechanical properties, the method and
process of manufacturing, the heat treatment, and the quality control measures.
Appendix E, given here as Table 3.3.5, is a list of the latest
approved ASTM editions and other B31.3-approved Standard
organization specifications. The allowable stresses for each alloy
to each specification are determined by the rules of the B31.3 Code
and noted in Appendix A-1.
3.3.9
References
1. ASME Boiler and Pressure Vessel Code Section II, Part C. The
American Society of Mechanical Engineers, 2015.
2. ASME Boiler and Pressure Vessel Code Section II, Part B, The
American Society of Mechanical Engineers, 2015.
3. ASTM DS-56JOL, Metals and Alloys in the Unified Numbering
System, The American Society for Testing Materials, 11th ed.
4. ASTM Annual Book of Standards, Section 2, Vols. 02.01, 02.02, and
02.04, The American Society for Testing Materials, 2016.
5. ASME Boiler and Pressure Vessel Code Section II, Part A. The
American Society of Mechanical Engineers, 2015.
6. ASME Boiler and Pressure Vessel Code Section II, Part D. The
American Society of Mechanical Engineers, 2015.
7. ASME Boiler and Pressure Vessel Code Section IX, The American
Society of Mechanical Engineers, 2015.
3.4
SECTION II, PART C: SPECIFICATION
FOR WELDING RODS, ELECTRODES,
AND FILLER METALS
3.4.1
Introduction
Welding plays a major role in the fabrication of pressure vessels and related components to the requirements of the ASME
B&PV Code. Reliable welding and brazing materials are required
to produce sound joints using one of the many welding and brazing processes available. The ASME B&PV Code [1] provides the
Welding Material Specifications acceptable for Code fabrication in
Section II, Part C (Specification for Welding Rods, Electrodes, and
Filler Metals). These are the welding filler metal specifications of
the AWS [2] adopted for use by the ASME. In this respect, Section
II, Part C is comparable to Sections II, Parts A and B that contain
the ASTM Material Specifications [3] adopted by the ASME. The
AWS Welding Material Specifications are prefixed as ANSI/AWS
to identify that these standards were developed in accordance with
the rules of the American National Standards Institute (ANSI) [4].
Welding and Brazing Material Specifications in Section II, Part
C are identical to the ANSI/AWS Specifications. However, once
the specification is adopted, the prefix changes from the letter “A”
to the letters “SFA.” For example, the ANSI/AWS specification
for carbon steel electrodes A5.1/A5.1M becomes SFA-5.1/SFA5.1M. Section II, Part C also includes appendices to the ANSI/
AWS Specifications that provide descriptions and explanations of
the classification system used for welding materials.
The suffix M indicates that the latest revision includes metric
equivalents. As AWS specifications are issued or revised the
metric units are now included. Additionally, the ISO designations are being listed in the electrode or filler metal classifications within the specification. Usually, this is for comparison
purposes only. However, SFA-5.34/SFA-5.34 uses both the
traditional and ISO formats in the classification. The dual classification extends to the marking and label that is affixed to the
electrode package.
Section II, Part C does not include all welding and brazing
materials available to the industry; instead, it includes only the
specifications applicable to B&PV Code construction. As explained
in other sections of the B&PV Code, particularly Section IX [5],
welding is not restricted to the use of the welding filler metals listed
in Section II, Part C; other welding materials can be used if they are
specified in Code Cases or if they are qualified separately. Code
Cases or separate welding procedure qualifications are generally
used in special cases in which a filler metal is formulated to meet
specific base metal properties or is a new material that has not yet
been classified in an ANSI/AWS Specification.
This chapter highlights the major features of the welding
material specifications contained in Section II, Part C and their
relationship to other sections of the B&PV Code. Included are
material descriptions, welding material applications, welding
material procurement, the filler metal certification system, and the
electrode classification system. The discussion that follows should
prove useful for one to gain a basic understanding of ASME/AWS
Welding Material Classification and Specification.
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TABLE 3.3.2 SPECIFICATIONS AND STANDARDS
(Source: ASME B31.1—2014 Edition, Power Piping)
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TABLE 3.3.2
SPECIFICATIONS AND STANDARDS (CONT’D)
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TABLE 3.3.2 SPECIFICATIONS AND STANDARDS (CONT’D)
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TABLE 3.3.2 SPECIFICATIONS AND STANDARDS (CONT’D)
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TABLE 3.3.2 SPECIFICATIONS AND STANDARDS (CONT’D)
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TABLE 3.3.2 SPECIFICATIONS AND STANDARDS (CONT’D)
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TABLE 3.3.2 SPECIFICATIONS AND STANDARDS (CONT’D)
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TABLE 3.3.3 APPENDIX REFERENCED STANDARDS [Note (1)]
(Source: ASME B31.1—2014 Edition, Power Piping)
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TABLE 3.3.3
APPENDIX REFERENCED STANDARDS (CONT’D)
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TABLE 3.3.3
APPENDIX REFERENCED STANDARDS (CONT’D)
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TABLE 3.3.3
APPENDIX REFERENCED STANDARDS (CONT’D)
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TABLE 3.3.4 SPECIFICATION INDEX FOR APPENDIX A
(Source: ASME B31.3—2014 Edition, Power Piping)
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TABLE 3.3.4
SPECIFICATION INDEX FOR APPENDIX A (CONT’D)
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TABLE 3.3.4
SPECIFICATION INDEX FOR APPENDIX A (CONT’D)
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TABLE 3.3.5 SPECIFICATION INDEX FOR APPENDIX E
(Source: ASME B31.3—2014 Edition, Power Piping)
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TABLE 3.3.5 SPECIFICATION INDEX FOR APPENDIX E (CONT’D)
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TABLE 3.3.5 SPECIFICATION INDEX FOR APPENDIX E (CONT’D)
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TABLE 3.3.5 SPECIFICATION INDEX FOR APPENDIX E (CONT’D)
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TABLE 3.3.5 SPECIFICATION INDEX FOR APPENDIX E (CONT’D)
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TABLE 3.3.5 SPECIFICATION INDEX FOR APPENDIX E
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3.4.2
History
The AWS was formed in 1919 when the National Welding
Council was discontinued. In 1935, the AWS and the ASTM both
formed the joint AWS–ASTM Committee on Filler Metal to provide standard specifications for welding rods, electrodes, filler
metals, and fluxes for the developing U.S. pressure vessel industry.
In 1969, this joint activity was dissolved and the AWS assumed
sole responsibility for welding-related materials. Section II, Part
C was developed by the ASME to include the Welding Material
Specifications published by the AWS and adopted by the ASME
for Code fabrication. In the 1968 edition of Section IX, the ASTM
Welding Material Specifications were assigned F-numbers, but by
the Winter 1970 addenda to Section IX, these had been replaced
with corresponding AWS Specifications.
Although Section II, Part C contains only ANSI/AWS Welding Material Specifications (at least at the time of this writing),
other recognized national and international standards can be
adopted into it. In 1992, the BPTCS endorsed the use of standards other than ANSI/AWS Specifications. The “Guideline on
the Approval of New Welding and Brazing Material Classifications under the ASME Boiler and Pressure Vessel Code” explains the process for adoption of new materials. This guideline
is located at the beginning of Section II, Part C. [Note to Editor.
This used to be true. With the revision of Mandatory Appendix
5, Section II, significantly more criteria were invoked for base
materials operating in, or near their creep regime. I suggest we
just end the sentence as shown.]
The AWS Specifications are developed and written by voluntary
industrial experts, much as the rules developed for pressure vessel
manufacturing in the ASME Code. The ANSI/AWS Specifications
are reviewed by the cognizant ASME Committees before they are
adopted into Section II, Part C. The Subcommittee on Welding
(Section IX) of the ASME B&PV Code Committees is responsible
for actions involving welding filler metals. Since the ASME and
the AWS maintain a close working relationship, the ANSI/AWS
Specifications are generally adopted in their entirety without modification by the ASME.
Technical inquiries to Section II, Part C are also handled by
the Standards Committee on Welding, Brazing and Fusing (Section IX). If questions arise involving Section II, Part C, these
inquiries should be submitted to the ASME B&PV Code Committee Secretary, as explained in Appendix I of Section II, Part
C. Generally, inquiries to Section II, Part C are referred to the
appropriate experts on the AWS committees on welding filler
metal for resolution.
3.4.3
Organization of Section II, Part C
Section II, Part C contains only those specifications that are
relevant to ASME Code fabrication. Included within these specifications are classifications of welding rods, electrodes, and filler
metals. Because all welding material classifications are contained in the specification, some materials may not be applicable
for ASME Code fabrication. Welding and brazing materials are
classified for all the common welding processes for joining the
ferrous and non-ferrous materials listed in the P-number tables
of QW/QB-422 in Section IX. P-numbers are groupings of base
metals in Section IX that reduce the required number of welding
and brazing procedure qualifications. The following is a listing
of the ASME-adopted ANSI/AWS Specifications that constitute
Section II, Part C:
t SFA-5.01M/SFA-5.01, Filler Metal Procurement Guidelines
t SFA-5.02/SFA-5.02M, Specification for Filler Metal Standard
Sizes, Packaging, and Physical Attributes
t SFA-5.1/SFA-5.1M, Specification for Carbon Steel Electrodes
for Shielded Metal Arc Welding
t SFA-5.2/SFA-5.2M, Specification for Carbon and Low-Alloy
Steel Rods for Oxyfuel Gas Welding
t SFA-5.3/SFA-5.3M, Specification for Aluminum and
Aluminum Alloy Electrodes for Shielded Metal Arc Welding
t SFA-5.4/SFA-5.4M, Specification for Stainless Steel
Electrodes for Shielded Metal Arc Welding
t SFA-5.5/SFA-5.5M, Specification for Low-Alloy Steel
Electrodes for Shielded Metal Arc Welding
t SFA-5.6/SFA-5.6M, Specification for Covered Copper and
Copper Alloy Arc Welding Electrodes
t SFA-5.7/SFA-5.7M, Specification for Copper and Copper
Alloy Bare Welding Rods and Electrodes
t SFA-5.8/SFA-5.8M, Specification for Filler Metals for
Brazing and Braze Welding
t SFA-5.9/SFA-5.9M, Specification for Bare Stainless Steel
Welding Electrodes and Rods
t SFA-5.10/SFA-5.10M, Specification for Bare Aluminum and
Aluminum Alloy Welding Electrodes and Rods
t SFA-5.11/SFA-5.11M, Specification for Nickel and Nickel
Alloy Welding Electrodes for Shielded Metal Arc Welding
t SFA-5.12/SFA-5.12M, Specification for Tungsten and
Tungsten Alloy Electrodes for Arc Welding and Cutting
t SFA-5.13, Specification for Solid Surfacing Welding Rods
and Electrodes
t SFA-5.14/SFA-5.14M, Specification for Nickel and Nickel
Alloy Bare Welding Electrodes and Rods
t SFA-5.15, Specification for Welding Electrodes and Rods
for Cast Iron
t SFA-5.16/SFA-5.16M, Specification for Titanium and
Titanium Alloy Welding Electrodes and Rods
t SFA-5.17/SFA-5.17M, Specification for Carbon Steel
Electrodes and Fluxes for Submerged Arc Welding
t SFA-5.18/SFA-5.18M, Specification for Carbon Steel
Electrodes and Rods for Gas Shielded Arc Welding
t SFA-5.20/SFA-5.20M, Specification for Carbon Steel
Electrodes for Flux Cored Arc Welding
t SFA-5.21, Specification for Bare Electrodes and Rods for
Surfacing
t SFA-5.22/SFA-5.22M, Specification for Stainless Steel
Electrodes for Flux Cored Arc Welding and Stainless Steel
Flux Cored Rods for Gas Tungsten Arc Welding
t SFA-5.23/SFA-5.23M, Specification for Low-Alloy Steel
Electrodes and Fluxes for Submerged Arc Welding
t SFA-5.24/SFA-5.24M, Specification for Zirconium and
Zirconium Alloy Welding Electrodes and Rods
t SFA-5.25/SFA-5.25M, Specification for Carbon and LowAlloy Steel Electrodes and Fluxes for Electroslag Welding
t SFA-5.26/SFA-5.26M, Specification for Carbon and LowAlloy Steel Electrodes for Electrogas Welding
t SFA-5.28/SFA-5.28M, Specification for Low-Alloy Steel
Electrodes and Rods for Gas Shielded Arc Welding
t SFA-5.29/SFA-5.29M, Specification for Low-Alloy Steel
Electrodes for Flux Cored Arc Welding
t SFA-5.30/SFA-5.30M, Specification for Consumable Inserts
t SFA-5.31, Specification for Fluxes for Brazing and Braze
Welding
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-49
t SFA-5.32/SFA-5.32M, Specification for Welding Shielding
Gases
t SFA-5.34/SFA-5.34M, Specification for Nickel-Alloy
Electrodes for Flux Cored Arc Welding
t SFA-5.36/5.36M, Specification for Carbon and Low-Alloy
Steel Flux Cored Electrodes for Flux Cored Arc Welding and
Metal Cored Electrodes for Gas Metal Arc Welding
Welding rods, electrodes, and filler metal are manufactured and
classified to the foregoing specifications. Additional materials
included in these specifications are gas tungsten arc welding
(GTAW) electrodes, welding fluxes, brazing filler metal, brazing
fluxes, and shielding gases. Classification is based on a combination
of chemical composition, strength, usability, toughness, hydrogen
content, and any special characteristics. Specification, SFA-5.01/
SFA-5.01M, is a guideline to simplify the procurement of welding
and brazing materials. Recently, SFA-5.02/SFA-5.02M was added
to consolidate packaging requirements into one specification.
3.4.4
AWS Welding Material Specifications
Two important features of Section II, Part C, aside from the
Welding Material Specifications, are SFA-5.01/SFA-5.01M and
the appendices for the individual specifications. As stated previously, SFA-5.01/SFA-5.01M is a valuable tool for determining
welding material procurement requirements, but it is also valuable
for obtaining explanations of lot classifications and testing levels.
The Annexes to the SFA specifications are excellent guides that
describe the individual electrodes, properties, and uses. If questions arise concerning the use or testing of a particular welding
electrode or filler metal, the annexes are good starting points for
finding answers. As the AWS specifications are revised, Annex A
in each specification now contains a comparison of the AWS classification with the ISO classification. However, the annexes are
not part of the specification but are included for information only.
Most electrodes have classifications that include usability characteristics and chemical composition requirements. Section IX
further defines these characteristics and requirements in paragraphs
QW-430 and QW-440 for welding qualification. The usability
characteristic of an electrode oftentimes determines the F-number
assigned in Table QW-432 of Section IX. F-numbers are referenced by the essential, supplementary essential, and nonessential
welding variables in Section IX for welding procedures and performance qualification. The chemical composition of the undiluted
weld deposit determines the A-number assigned in Table QW-442
of Section IX. A-numbers are referenced in the welding variables
of Section IX for welding procedure qualification requirements
involving ferrous metals. F-numbers and A-numbers for welding
and brazing materials are highlighted throughout this chapter for
many of the commonly used electrode classifications.
Each of the individual Welding Material Specifications contain
acceptance and certification statements. The following are the
statements from SFA-5.14/SFA-5.14M [6].
For acceptance:
Acceptance of the filler metal shall be in accordance with the
provisions of AWS A5.01M/A5.01 (ISO 14344 MOD), (Welding
Consumables—Procurement of Filler Materials and Fluxes).
For certification:
By affixing the AWS Specification and Classification designations to the packaging, or the classification to the product, the
manufacturer certifies that the product meets the requirements of
this specification.
Both “acceptance” and “certification” of welding materials are
very important to ASME Code users. Depending on the fabrication section of the Code, the User should understand these basic
requirements so that welding material is procured correctly. The
fact that a Welding Material Manufacturer places the AWS Specification and classification on the container does not mean that the
tests required by the specification are conducted on that particular lot of welding materials. It means only that the Manufacturer
conducted the required testing on material representative of that
welding material. (Further discussion on acceptance and certification is covered in the discussion on SFA-5.01/SFA-5.01M.)
The following are summaries of the contents of the individual
Welding Material Specifications. The purpose of these discussions
is to explain the Welding Material Specifications and relate them
to ASME requirements. When possible, references are made to
ASME base metal specifications that can be welded with a specific
classification of electrode, rod, or filler metal. Such references are
intended as examples only rather than a complete listing of all the
base metals for which each welding material is suitable.
3.4.4.1 SFA-5.01M/SFA-5.01: Welding Consumables—
Procurement of Filler Materials and Fluxes Filler metal procurement guidelines are published in Section II, Part C to provide
the procurement and acceptance criteria as prescribed in each
of the Welding Material Specifications. The guidelines provide
detailed methods by which the individual filler metals are classified and tested. When procuring materials for ASME Code
fabrication, regardless of whether a Certificate of Conformance
or a Certified Material Test Report is required, these guidelines
should be followed. As each specification states, the acceptance
of the welding material is in accordance with the provisions of
SFA-5.01M/SFA-5.01.
The guidelines begin with definitions that describe various
aspects or characteristics of welding materials, such as heats, lots,
batches, blends, and mixes. These definitions are followed by
specific lot classifications based on the type of welding material
being procured. Two to five lot classifications describe the size of
a production run of welding materials depending on the product
form: covered electrodes, bare wire, flux-cored electrodes, and
flux. These classifications allow the purchaser to specify the level
of control and the lot size necessary to meet the application. If
the welding material is for Section III, Division 1, Class 1 nuclear
component fabrication [7], the lot classification selected should
meet the requirements of Section III, Subsection NB, paragraph
NB-2400. If the application does not require lot controls, these
classifications are less important.
SFA-5.0M/SFA5.011 also includes testing schedules so that
an appropriate level of testing can be specified when welding
materials are procured. Testing levels begin with Schedule 1 or F,
which is the Manufacturer’s standard. If welding materials are procured without specified requirements (i.e., off the shelf), this level
of testing is what the Manufacturer would provide. However, some
manufacturers’ program require testing all material and CMTR’s
are provided, yet they indicate Schedule F because it is their “standard”. Each manufacturer or supplier should be consulted to determine what their quality program requires. The welding material
would be supplied with the required markings on the container to
serve as certification that the welding material meets the specification requirements. However, the markings certify only that material
3-50 t Chapter 3
representative of that being delivered was tested at some time in
accordance with the Material Manufacturer’s standard practice. A
typical certification would be provided upon request. If the purchaser wants a Certified Material Test Report for the tests required
for the classification of each lot shipped, Schedule 3-6, H, I, J or
K would be specified, which requires that the Welding Material
Manufacturer perform all the classification testing required by the
specification on the lot of material ordered or as required by the
Schedule specified. A Certified Material Test Report would then
represent the actual lot or lots of welding material being delivered.
Schedule 6 or K, a level of testing specified by the purchaser, can
be selected when filler metal to Section III NB or other rigorous
criteria are required. For Section III welding materials, the level
of testing is based on the design of the component, the welding
procedure and postweld heat treatment that will be used in fabrication. Therefore, the purchaser might list the tests and acceptance
criteria, including certification requirements, in the purchase order.
The final guideline is one that illustrates and gives examples of
methods for use when welding materials are procured. One should
remember the importance of ordering the correct welding material
to meet specific Code requirements. The purchaser’s acceptance
of the wire can be satisfied only if the correct lot classification and
level of testing are included in the order, in addition to the quantity, size, and type of filler metal or electrodes. Example tables are
included for the popular product forms to assist the User in providing all the criteria required.
3.4.4.2 SFA-5.02/SFA-5.02M: Specification for Filler Metal
Standard Sizes, Packaging, and Physical Attributes This
specification was published in 2007. Details regarding sizes and
packaging that previously resided in the filler metal specifications
were placed in SFA-5.02/SFA-5.02M. It takes into account the
requirements of a similar specification, ISO 544, and allows classification in both U.S. Customary units and Metric (SI) units. As
filler metal specifications are revised, sizes and packaging sections
will be removed and SFA-5.01/SFA-5.02M will be referenced.
3.4.4.3 SFA-5.1/SFA-5.1M: Specification for Carbon Steel
Electrodes for Shielded Metal Arc Welding It is appropriate that
SFA-5.1/SFA-5.1M is the first weld filler metal specification in
Section II, Part C. Among the first classifications developed were
those for carbon steel electrodes, which are widely used for welding plain carbon steel in B&PV Code applications. Electrodes in
this specification are used mainly for shielded metal arc welding
(SMAW) of base metals grouped as P-Number 1 in QW/QB-422
of Section IX.
Covered electrodes are classified in SFA-5.1/SFA-5.1M mainly
by strength and usability. Figure 3.4.1 illustrates a typical electrode
classification for this specification. The letter “E” at the beginning
of the classification stands for electrode; the first two numbers
that follow—either a 60 or 70—designate the minimum required
tensile strength in ksi (1,000 psi), and the third number designates
welding position usability. For example, the “1” in E6010 indicates
that the electrode is usable in all positions (flat, horizontal, vertical,
and overhead). The third number is then taken together with the
fourth number (i.e., 10 in E6010) to designate the type of current
and the type of electrode covering or coating.
Sometimes, optional supplemental designators are used to
further identify electrodes that meet certain addition requirements.
The “–1” designator in E7024-1 means that the electrode will meet
impact requirements at a lower temperature than that required for
the classification. Low-hydrogen electrodes can also be given the
FIG. 3.4.1 SFA-5.1/SFA-5.1M: TYPICAL SMAW CARBON
STEEL ELECTRODE CLASSIFICATION (See Figure 10
in SFA-5.1M for metric designation.)
optional designator “R,” such as in E7018R, to indicate that the
electrodes meet low-moisture-absorption (i.e., moisture-resistant)
requirements. Even more optional supplemental designators can
be included for moisture or hydrogen testing. If the designator
“HZ” follows the four-digit classification, the electrode will meet
the requirements for an average diffusible hydrogen content of not
more than “Z” ml/100 g of deposited metal when tested. Electrodes
shall be tested in an unconditioned state unless otherwise recommended by the manufacturer. Therefore, an E7018-1H4 electrode
produces a minimum 70 ksi tensile strength weld deposit (70),
has a low-hydrogen coating for alternating current (ac) or direct
current (dc) welding in all positions (18), has improved fracture
toughness (–1), and meets a maximum of 4 ml/100 mg of diffusible hydrogen (H4). However, many E7018 products will meet the
toughness criteria of E7018-1 when tested.
Covered electrodes are composed of a covering and a carbon steel
core wire. Flux, minimal alloying, and iron powder (in some classifications) are used to make the covering. The core wire is usually low
carbon steel that has a chemical composition different from that of
the weld deposit. Low-hydrogen electrodes (E7015, E7016, E7018,
E7018M, E7028, and E7048) have low-moisture (i.e., low-hydrogen)
mineral coverings. The E60XX electrodes have cellulose, titania, or
similar coverings that are not low in hydrogen. Both types of electrodes are acceptable for welding carbon steels for which hardenability is not a concern. Under certain conditions, hydrogen can lead
to cracking in either the heat-affected zone or the weld deposit in
hardenable steels. One source of hydrogen is the moisture in the electrode coverings, for which reason low-hydrogen electrodes should be
selected for steels susceptible to hydrogen-induced cracking.
Electrodes classified in this specification are manufactured to
meet moisture limits based on the type of covering and strength
of the weld metal. Therefore, proper storage, treatment, and
handling of electrodes are all necessary. Packaging normally provides some degree of moisture protection during storage. After the
electrodes are removed from the packaging, low-hydrogen electrodes are normally stored in heated containers in accordance with
the Manufacturer’s recommendations. Unlike the low-hydrogen
electrodes in this specification, cellulose coverings for E6010 and
E6011 electrodes need moisture levels of 3–7% for their proper
operation. Heated storage is not recommended and drying cellulosic electrodes may adversely affect their operation.
3.4.4.4 SFA-5.2/SFA-5.2M: Specification for Carbon and
Low-Alloy Steel Rods for Oxyfuel-Gas Welding This specification includes carbon and low-alloy steel filler metal used for
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-51
oxyfuel-gas welding (OFW). The letter “R” in the designation
stands for rod. Filler metal made to the requirements of this
specification is supplied in the bare wire form and usually in cut
straight lengths. Number designations following the letter “R”
represent the minimum tensile strength in ksi (i.e., 1,000 psi).
Although OFW was one of the first welding processes used for
joining metals, OFW has limited usage in the manufacture of pressure vessels to the B&PV Code. These filler metals have also been
used with GTAW where lower strength weld deposits are required.
3.4.4.6 SFA-5.4/SFA-5.4M: Specification for Stainless Steel
Electrodes for SMAW Covered electrodes manufactured to this
specification are used for depositing stainless steel weld metal
with the SMAW process. Weld metal deposited by these electrodes has a chromium content of 10.5% or greater and an iron
content that is greater than that of any other element. Stainless
steel electrodes have a wide range of uses for corrosion resistance,
cryogenic service, and heat-resistant applications in the fabrication
of ASME pressure vessels and piping.
Unlike the carbon steel electrodes of SFA-5.1, stainless steel
classifications represent the chemical composition rather than the
tensile properties. The last two numbers define positional usability
and electrical characteristics. Therefore, an E308L-16 electrode is
defined by the letter “E” for electrode, the “308L” for the chemical composition (nominal 19% Cr and 10% Ni with a low carbon
content). The last two number designators, “–16,” indicate all position usability with ac or dc electrode positive (dcep). Figure 3.4.2
illustrates another common stainless steel electrode classification.
This specification allows an electrode to be classified under
more than one classification if all requirements are met for those
classifications. However, electrodes may not be classified under
more than one of the following designations: EXXX-15, EXXX16, EXXX-17, EXXX-25, or EXXX-26. For example, an E308-16
electrode may also be dual-classified as an E308H-16 electrode,
but it cannot be classified as E308-15.
A stainless steel electrode is composed of a core wire and a flux
covering that determines the usability classification of the electrode. It should be noted that the core wire does not necessarily
contain all the elements that determine the weld deposit composition. Depending on the type of electrode, the covering can contribute some or most of the alloying elements.
The composition ranges of weld metal deposited by stainlesssteel electrodes are grouped as A-No. 6–9 in QW-442 of Section
IX. Stainless-steel electrodes are grouped as F-Nos. 1, 4, and 5 in
QW-432 of Section IX. Table 3.4.1 has a listing of each electrode
classification and the corresponding F-Number and A-Number.
Although the amount of ferrite in the weld deposit is not a factor
for classification, it is an important characteristic in stainless steel
welding. Stainless steel welds are more susceptible to cracking or
fissuring during welding than welds made with carbon steel electrodes. Ferrite in the deposit helps to reduce this tendency for hotcracking and strengthens the final weld. In some corrosion-resistant
or high temperature applications, electrodes are used that deposit
welds with little or no ferrite because ferrite may have a detrimental
effect. Electrodes classified as E310, E320, E320LR, E330, E383,
and E385 deposit fully austenitic (i.e., no ferrite) weld metal. Ferrite is also known to reduce toughness in cryogenic service and to
transform into the brittle sigma phase in high-temperature service.
Austenitic weld deposits that are high in ferrite can also transform
to the sigma phase during postweld heat treatments.
It is not uncommon to specify ferrite ranges to avoid problems
associated with too little or too much ferrite, depending on the
application. Ferrite can be determined by chemical analysis of
the undiluted weld deposit or be measured with various magnetic
instruments. The term ferrite number (FN) was selected by the
Welding Research Council (WRC) to be used in lieu of percent
ferrite for the magnetic-measuring instruments. The purpose of the
ferrite number is to clearly indicate that ferrite readings are obtained
using an instrument calibrated in accordance with the WRC’s
calibration procedure. The AWS publishes the WRC’s calibration
procedure requirements in AWS A4.2 (Standard Procedures for
Calibrating Magnetic Instruments to Measure the Delta Ferrite
Content of Austenitic Stainless Steel Weld Metal). When the ferrite
content is calculated or predicted from the chemical composition of
the weld deposit, the WRC–1992 Diagram is specified [9]. Figure
3.4.3 is a reprint of the WRC-1992 Diagram as taken from Section
III, NB-2433.1-1. With either magnetic measurement or chemical
analysis using the WRC-1992 Diagram, the amount of ferrite in
the weld deposit is reported as an FN rather than as a percent. The
ferrite number corresponds to percent ferrite (up to 10 FN).
The following text gives brief descriptions of the stainless steel
electrodes used with SMAW. Included in these descriptions are
examples of base metals that can be welded with these electrodes.
FIG. 3.4.2 SFA-5.4/SFA-5.4M: TYPICAL SMAW STAINLESS
STEEL ELECTRODE CLASSIFICATION
3.4.4.6.1 Nitrogen-Strengthened, Austenitic Stainless Steel
Electrodes. The E209, E219, and E240 electrodes are intended
for welding nitrogen-strengthened, austenitic stainless steel base
metals having comparable compositions. These types of stainless steels exhibit high strength and toughness over a wide range
of temperatures. Nitrogen alloying also reduces the tendency
for intergranular carbide precipitation in the weld area, thereby
increasing its resistance to intergranular corrosion. Typically,
E209 is used for welding type XM-19 (UNS S20910), which is
listed in ASME Material Specifications SA-182, SA-240, SA-249,
SA-312, SA-358, SA-403, SA-479, SA-813, and SA-814. E219
is designed for welding type UNS S21900 base metal. E240 is
typically used for welding type XM-29 (UNS S24000), which is
3.4.4.5 SFA-5.3/SFA-5.3M: Specification for Aluminum
and Aluminum Alloy Electrodes for SMAW Aluminum and
aluminum alloy electrodes produced to this specification are used
for SMAW. As with the electrodes classified in SFA-5.1, the letter
“E” in the designation stands for electrodes. However, the numbers in the designation are based on the Aluminum Association’s
[8] alloy identification of the alloy type rather than tensile strength
and usability. Aluminum and aluminum alloy type SMAW has
largely been replaced with gas metal arc welding (GMAW) and
gas tungsten arc welding (GTAW). Therefore, electrodes manufactured to this specification will see little, if any, use for ASME
pressure vessel or component fabrication.
3-52 t Chapter 3
TABLE 3.4.1
SFA-5.4/SFA-5.4M: A-NUMBERS FOR WELD METAL DEPOSITS OF STAINLESS STEEL
listed in ASME Material Specifications SA-240, SA-249, SA-312,
SA-358, SA-479, SA-688, SA-813, and SA-814. Additionally,
these electrodes are used for welding dissimilar alloys of carbon
steel and stainless steel, and also for corrosion-resistant overlay.
E240 can be used in cladding or overlay applications for wear
resistance as well.
3.4.4.6.2 Austenitic Stainless Steel Electrodes. The E308
series of electrodes typically have wide ASME Code usage in
the welding of Type 304 stainless steels listed as P-No. 8 in QW/
QB-422 of Section IX. Type 304 (UNS S30400) or type 304L
(UNS S30403) are the most common stainless steels welded
with either E308 or E308L. Most of the 304 stainless steels are
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-53
TABLE 3.4.1
SFA-5.4/SFA-5.4M: A-NUMBERS FOR WELD METAL DEPOSITS OF STAINLESS STEEL (CONT’D)
listed in ASME Material Specifications SA-182, SA-213, SA-240,
SA-249, SA-312, SA-336, SA-358, SA-376, SA-403, SA-409,
SA-430, SA-479, SA-666, SA-688, SA-813, and SA-814. The
“L” grades are generally selected for improved corrosion resistance because the 0.04% maximum carbon content of weld metal
deposited by E308L reduces the possibility of intergranular carbide precipitation.
The E309 series of electrodes contains more chromium and
nickel than the E308-type electrodes. These electrodes are used to
weld base metals such as UNS S30900, S30908, S30909, S30940,
and S30941. Base metals of these compositions are generally listed
in the same ASME Material Specifications as UNS S30400.
Both E309 and E309L are commonly used for the first layer
when a corrosion resistant stainless steel overlay is applied. The
remaining layers are typically deposited with E308 or E308L.
Because of their richer chemical composition, electrodes in this
group are also good for joining dissimilar metals, such as joining
Type 304 stainless steel to carbon or low-alloy steel.
3-54 t Chapter 3
FIG. 3.4.3
WRC-1992 DIAGRAM FOR FERRITE NUMBER (FN) DETERMINATION (Source: Fig. N8-2433.1-1, Section III of
the ASME B&PV Code)
Electrodes in the E316 series are generally used for welding
base metals of like designations (316, 316L, etc.). Molybdenum
strengthens these stainless steels and provides creep resistance at
elevated temperatures. Type 316 base metals appear in most of the
same ASME Material Specifications as UNS S316XX.
The E347 stainless steel electrodes have columbium (niobium)
or columbium (niobium) plus tantalum to reduce the possibility of intergranular chromium carbide precipitation for increased
intergranular corrosion resistance. These electrodes are usually
used for welding stainless steels stabilized with columbium (niobium) or titanium, such as Type 347 (UNS S347XX) or Type 321
(UNS S321XX), respectively. Type 347 and 321 stainless steels
are grouped as P-No. 8 in QW/QB-422 in Section IX.
generally recommended. These electrodes can be used to weld
UNS S41000 or S41008, listed in ASME Material Specifications
SA-240, SA-268, and SA-479. E410NiMo is typically used for
welding castings such as Type CA6NM, listed in ASME Material
Specification SA-487.
3.4.4.6.3 Austenitic Manganese Steel Electrodes. Type E307
electrodes are used primarily for moderate strength welds with
good crack resistance between dissimilar steels such as austenitic
manganese steel and carbon steel forgings or castings.
3.4.4.6.6 Precipitation-Hardening Stainless Steel Electrodes.
The E630 electrodes are designed for welding Type 630
(UNS S17400) precipitation-hardening stainless steel and similar steel. The final weldment may be used as-welded, or
welded and precipitation-hardened, or welded, solution-treated,
and precipitation-hardened (depending on the application).
Precipitation-hardening stainless steel materials are not listed in
QW/QB-422 of Section IX.
3.4.4.6.4 Martensitic Stainless Steel Electrodes. The E410
electrodes produce a martensitic, nominal 12% chromium (12Cr)
alloy deposit. Both preheat and postweld heat treatments are
3.4.4.6.5 Ferritic Stainless Steel Electrodes. The E409Nb and
E430 electrodes usually require both preheat and postweld heat
treatments to obtain optimum mechanical properties and corrosion resistance. P-No. 7 base metal Types 405 (UNS S40500) 409
(UNS S40900) and 430 (UNS S43000), listed in ASME Material
Specifications SA-240, SA-268, and SA-479, can be welded with
these filler metals.
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-55
3.4.4.6.7 Duplex Stainless Steel Electrodes Type E2209,
E2553, E2593, E2594, and E2595 are duplex stainless steel electrodes. Weld metal deposited by these electrodes has an austeniticferritic (duplex) microstructure. E2209 is used primarily to weld
duplex stainless steels such as UNS S31803, listed in ASME
Material Specification SA-240. UNS S31803 is grouped as P-No.
10H, Group 1 in QW/QB-422 of Section IX. E2553 and E2593 are
used primarily to weld duplex stainless steels containing approximately 25% chromium. E2594 and E2595 are used to weld the
super-duplex stainless steels with a pitting resistance equivalent
number (PREN) of at least 40.
3.4.4.7 SFA-5.5/SFA-5.5M: Specification for Low-Alloy
Steel Electrodes for SMAW Contained in this specification
are the classification requirements for low-alloy steel electrodes
used for SMAW of carbon and low-alloy steels. These electrodes
include steel alloys in which no single alloying element exceeds
10.5%. As shown in Figure 3.4.4, the classification system is
similar to that for SFA-5.1/SFA-5.1M. However, there are more
designators because these electrodes cover a wider range of steels.
Mechanical properties of the weld metal deposit are also required
in the as-welded or postweld heat treated condition.
Because hydrogen can pose a significant problem when welding
low-alloy steels, moisture testing of the covering is required to
classify some of the electrodes to this specification. However,
the supplementary tests for absorbed moisture (the “R” designation) and the diffusible hydrogen (the “HZ” designation) are not
required for classification of the low-hydrogen electrodes. Optional supplemental designators are included in the SFA-5.1/SFA5.1M discussion.
This specification also includes a “G” classification that
includes electrodes classified as E(X)XXYY-G. The “G” indicates
a general electrode classification with requirements usually agreed
to by both the purchaser and the supplier. The AWS classifications
now include both the U.S. Customery, Unit designation and the
International System of Units (SI) in the Tables. Electrodes may
be classified as both U.S. and metric (i.e., E7018x and E4918-x).
Electrodes classified in this specification require mechanical
properties and soundness to be determined from a groove weld
test assembly. The groove test assembly usually consists of a base
metal having similar characteristics to the tested electrode. The test
plate is welded following the welding procedure requirements of
FIG. 3.4.4 SFA-5.5/SFA-5.5M: TYPICAL SMAW LOWALLOY STEEL ELECTRODE CLASSIFICATION (See Figure 1
in SFA-5.5M for metric designation.)
SFA-5.5 for the classified electrode. After postweld heat treatment
(if required), testing for classification may include radiography,
tension testing, and toughness testing. Since most of these electrodes are of low-alloy steel, the majority of weld metal deposits
are required to be tested in the postweld heat-treated rather than the
as-welded condition.
Users of Section III in the ASME Code should note that the testing required for classification is different than the testing required
by NB-2400. To certify that the weld material is in accordance
with NB-2400, the welding process and conditions that represent
Section III fabrication requirements must be used for welding the
test assembly. Mechanical testing of the weld is then performed
to the NB-2400 requirements not the Section IIC requirements.
For example, five toughness specimens are required to be tested
at temperatures listed in SFA-5.5/SFA-5.5M for classification. If
weld metal deposited from this electrode requires impact testing to
Section III, the test temperature and toughness requirements would
be determined by the component design. In addition, only three
Charpy V-notch impact specimens would be required.
SFA-5.5/SFA-5.5M contains a variety of low-alloy steel electrodes having different chemical compositions and mechanical
properties. Electrodes can be selected to deposit weld metal that
closely match the chemical composition and the mechanical properties of the base metal being welded. Table 3.4.2 contains a listing
of the electrode F-numbers from QW-432 and the A-numbers from
QW-442 of Section IX for undiluted weld metal deposit. The various types of electrodes are also discussed briefly in the following
paragraphs.
3.4.4.7.1 Carbon Molybdenum (C–Mo) Steel Electrodes.
The E70YY electrodes are similar to carbon steel electrodes
except for the addition of approximately ½% molybdenum for
increased strength, especially at elevated temperatures. ASME
Material Specifications SA-204, Grade A plate (UNS K11820)
and SA-335, Type P1 pipe (UNS K11522) are typically welded
with these electrodes. These base metals are grouped as P-No. 3,
Group 1 in QW/QB-422 of Section IX.
3.4.4.7.2 Chromium Molybdenum (Cr–Mo) Steel Electrodes.
The EX01Y-BX and EX01Y-BXL low-hydrogen electrodes
produce deposits ranging from ½%–9% chromium and ½%–1%
molybdenum. These electrodes are used for vessels and components, such as those of Section I (Power Boilers) that are designed
for high-temperature service. SMAW with Cr-Mo electrodes generally requires both preheat and postweld heat treatment. Base metals that can be welded with these electrodes are grouped as P-Nos.
4, 5A, 5B, 5C and 15E in QW/QB-422 of Section IX.
The 9Cr-1Mo electrodes modified with niobium (Nb) and vanadium (V) are classified as E90XX-B9. These electrodes are used to
weld the creep strength-enhanced ferritic (CSEF) alloys which are
grouped as P-No. 15E in Section IX Table QW/QB-422. Section
IX elected to group the CSEF alloys in P-No. 15A through 15F,
because the microstucture of CSEF alloys require more controls
for welding and post weld heat treatment (PWHT) than required
for standard Cr-Mo steels. Thermal treatment of these alloys is
critical and must be closely controlled. Additionally, restrictions
are imposed on the Mn and Ni to ensure the PWHT can be maintained below the lower transformation temperature.
3.4.4.7.3 Nickel Steel (Ni) Electrodes. The EX01Y-CX and
EX01Y-CXL electrodes are produced to have nickel contents with
3-56 t Chapter 3
TABLE 3.4.2
SFA-5.5/SFA-5.5M: A-NUMBERS AND F-NUMBERS FOR WELDING ELECTRODES OF LOW-ALLOY STEEL
3.4.4.7.4 Nickel Molybdenum (Ni–Mo) Steel Electrodes. The
E8018-NM1 electrodes contain approximately 1% nickel and ½%
molybdenum. Typical applications include the welding of high
strength, low-alloy, or microalloyed structural steels.
3.4.4.7.6 Other Low-Alloy Steel Electrodes. The E(X)X01YM(1) electrodes are low-hydrogen electrodes designed to weld
the high-yield strength steels. EX010-P1 electrodes have cellulose
coverings and are intended to weld API-5L-X52 and API-5L-X65
piping. EX015-WX electrodes are low-hydrogen electrodes
designed to weld deposits that match the corrosion resistance and
coloring of the ASTM weathering type structural steels, such as
ASTM A242 and A588.
3.4.4.7.5 Manganese Molybdenum (Mn–Mo) Steel Electrodes.
The E(X)X01Y-DX electrodes produce deposits with a nominal
½% manganese and 1/3%–2/3% molybdenum. These electrodes
are designed to match the mechanical properties and corrosion
resistance of low-alloy steels, such as ASME SA-302, Grade B.
3.4.4.8 SFA-5.6/SFA-5.6M: Specification for Covered
Copper and Copper Alloy Arc Welding Electrodes This
specification provides the requirements for classifying covered
copper and copper-alloy electrodes used for SMAW. Welding
electrodes in this specification are classified based on the chemical
five nominal levels of 1%, 1 ½%, 2 ½%, 3 ½%, and 6 ½% nickel.
These low-hydrogen electrodes each have good notch toughness
at low temperatures.
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-57
TABLE 3.4.2
SFA-5.5/SFA-5.5M: A-NUMBERS AND F-NUMBERS FOR WELDING ELECTRODES OF LOW-ALLOY STEEL
(CONT’D)
composition of the undiluted weld metal deposit. The copper content exceeds that of any other element. The classification is similar
to the stainless steel electrodes in that the designators following
the letter “E” represent the chemical composition of the weld
deposit. Electrodes in this specification are used to weld a wide
range of copper-based alloys, such as copper, aluminum bronze,
phosphorous bronze, silicon bronze, and copper nickel.
3.4.4.9 SFA-5.7/SFA-5.7M: Specification for Covered Copper
and Copper Alloy Bare Welding Rods and Electrodes This
specification is similar to SFA-5.6 except that this specification
provides the requirements for classifying covered copper and copper alloy bare welding rods and electrodes. (Bare welding rods
and electrodes are also commonly referred to as bare wire or filler
metal.) These filler metals are typically used for GTAW, GMAW,
and plasma arc welding (PAW). Classification is based on the
chemical composition of the filler metal rather than the undiluted
weld-metal deposit. These filler metals follow the same general
classification system as the covered electrodes of SFA-5.6, except
that the prefix “ER” for bare electrodes and rod replaces the “E”
for electrode. Applications for these filler metals are generally the
same as those for the copper and copper alloy covered electrodes.
3-58 t Chapter 3
TABLE 3.4.2
SFA-5.5/SFA-5.5M: A-NUMBERS AND F-NUMBERS FOR WELDING ELECTRODES OF LOW-ALLOY STEEL
(CONT’D)
3.4.4.10 SFA-5.8/SFA-5.8M: Specification for Filler Metals
of Brazing and Braze Welding This is the only specification for
brazing filler metals that is referenced in Section IX (QB-Brazing).
Although this specification includes materials for braze welding, the main application for these materials is for brazing. Filler
metals classified in this specification include all metal and alloy
compositions for brazing, with or without flux and in protective
atmospheres. Standard forms include wire, strip, sheet, foil, rod,
powder, and paste.
The brazing filler metals covered by this specification are classified according to their chemical composition. Defining the filler
metal starts with “B” for brazing, followed by a chemical symbol
(such as Cu) to identify the major element. The remaining elemental symbols indicate the principal alloying elements; for example,
BCuP contains the primary element of copper with phosphorous
alloying. Filler metals identified by the prefix “RB” indicate that
the filler metal is suitable for use as a brazing rod for braze welding
and as a brazing filler metal. Typically, the RBCuZn classifications
are used in braze welding. Filler metal classifications for vacuum
service are similar to those for other filler metals, except that the
letter “V” appears in the classifications (e.g., BVAg-8). Devices
brazed by the use of these filler metals are intended to operate in
vacuums regardless of the atmosphere used in brazing the base
metals. Vacuum service filler metals are manufactured to reduce
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-59
the high vapor pressure impurities. Grade 1 filler metals meet more
stringent requirements for the high vapor pressure impurities than
those of Grade 2.
As defined by the AWS:
Brazing is a group of metal joining processes which produces
coalescence of materials by heating them to a suitable temperature and by using a filler metal having a liquidus above
840°F (450°C) and below the solidus of the base materials.
The filler metal is distributed between the closely fitted surfaces of the joint by capillary action.
In braze welding, the primary difference is that the filler is not
distributed in the joint by capillary action. The following paragraphs briefly discuss the brazing filler metals.
3.4.4.10.1 Brazing Filler Metal Classifications. The BAg
(silver) filler metals are widely used for joining steel, stainless
steel, copper, and copper alloys. The alloys in this group are commonly referred to as silver solders. These filler metals exhibit
good brazing characteristics and properties. As with the majority
of brazing applications, lap joints are usually employed with tight
joint clearances. When the filler metals are used with torch brazing, the filler metal can be preplaced (such as brazing rings) or
fed manually into the joint. Brazing flux is generally required.
Because cadmium fumes are poisonous, many of the alloys in this
group were developed to eliminate the cadmium; these are commonly known as cadmium-free or cad-free brazing filler metals.
BAu (gold) filler metals are used for the brazing of iron, nickel,
and cobalt base metals in which better ductility, greater oxidation
resistance, or greater corrosion resistance is required. BAu is commonly used on thin metals for induction, furnace, or resistance
brazing in a protective atmosphere.
BAlSi (aluminum–silicon) filler metals are used for joining
aluminum and aluminum alloys such as 1060, 1350, 1100, 3003,
3004, 3005, 5005, 5050, 6053, 6061, 6951, 7005, 710.0, and 711.0.
Because aluminum readily oxidizes, brazing flux is essential for all
brazing processes except vacuum brazing.
BCuP (copper–phophorous) filler metals are used primarily
for joining copper and copper alloys. BCuP-filler metals are used
extensively with manual torch brazing, but they are suitable for
all brazing processes. These filler metals are self-fluxing when
used on copper. When copper alloys are brazed, a brazing flux
is recommended.
BCu (copper) and RBCuZn (copper–zinc) filler metals are used
for joining both ferrous and nonferrous metals. BCu is commonly
used in furnace brazing applications for joining ferrous metals,
nickel alloys, and copper nickel alloys. RBCuZn filler metals,
particularly RBCuZn-B, are commonly used for braze welding
applications.
BNi (nickel) filler metals are generally used for their corrosionresistant and heat-resistant applications. The BNi-filler metals
have excellent properties at high-service temperatures and are
well-suited for vacuum service applications because of their low
vapor pressure.
3.4.4.11 SFA-5.9/SFA-5.9M: Specification for Bare Stainless
Steel Welding Electrodes and Rods This specification is similar to SFA-5.4/SFA-5.5M for covered electrodes except that it
includes filler metal for use with GTAW, GMAW, PAW, and
submerged arc welding (SAW) with flux. Filler metal classified
in this specification is available as wire, strip, composite metal-
cored, and stranded-wire or rod. Weld metal deposited by these
electrodes or rods has a minimum chromium content of 10 ½%
and an iron content that is greater than that of any other element.
Stainless steel filler metals see a wide range of uses for cryogenicservice, corrosion-resistant, and heat-resistant applications in the
fabrication of ASME pressure vessels and piping.
Classification of these welding materials follows that of the
SFA-5.4/SFA-5.4M stainless steel electrodes. The main difference is that the designation begins with the letters “ER” to denote
solid wire or rods. SFA-5.9/SFA-5.9M also allows filler metals to
have more than one classification, provided all the requirements
are met for those classifications. For example, an ER308 filler
metal may also be classified as ER308H. Mechanical properties
are not included in the classification of filler metals in this specification; however, the tensile properties shown in SFA5.4/SFA5.4M are generally applicable to the weld metal deposited by these
filler metals.
Chemical composition is determined by analysis of the solid or
product form except for composite and stranded electrodes, which
are classified by analysis of the undiluted weld metal deposit. Both
Sections IX and III [1] give additional requirements for the chemical analysis of filler metal and electrodes. QW-404.5 is an essential
variable in Section IX for the welding procedure qualification; it
details the chemical analysis requirements that are used to determine A-Numbers for ferrous metals. Section III, NB-2432 contains
the requirements for chemical analysis of welding materials to be
used for the fabrication and repair of Class 1 nuclear components
or vessels.
Stainless steel filler metals in this specification fall within
A-Nos. 6–9 composition ranges in QW-442 of Section IX. All bare
wires, composite wires, or strips in this specification are grouped
as F-No. 6 in QW-432. Table 3.4.3 lists the electrode classification
and the corresponding A-Number and F-Number.
As with all stainless steel materials, ferrite is important in reducing the tendency for hot-cracking and for strengthening the final
weld deposit. Although ferrite is not present in all classifications in
this specification, it is beneficial when highly restrained joints or
heavy sections are welded. Some variations of ferrite in the deposit
can be expected when the same filler metal is used with different
welding processes or welding techniques.
Ferrite determination is not required to classify filler metal
or electrodes in this specification. However, the purchaser may
impose ferrite controls when ordering filler metal to ensure sound
welds for the selected welding process or procedure. As explained
in the discussion of SFA-5.4/SFA-5.4M, ferrite can be determined by chemical analysis of the undiluted weld deposit or be
measured with various magnetic instruments. Because the chemical composition of the solid or product form is required to classify
materials in this specification, ferrite is commonly determined by
chemical analysis.
This specification includes welding materials for use on a wide
range of stainless steel base metals. The following paragraphs
briefly discuss some different types of stainless steel filler metals.
3.4.4.11.1 Nitrogen-Strengthened, Austenitic Stainless Steel
Electrodes and Rods. The ER209, ER218, ER219, and ER240
filler metals are intended for welding nitrogen-strengthened,
austenitic stainless steels that exhibit high strength and toughness over a wide range of temperatures. Nitrogen alloying also
reduces the tendency for intergranular carbide precipitation in the
weld area, thereby increasing its resistance to intergranular corrosion. Typically, ER209 can be used for welding type XM-19
3-60 t Chapter 3
TABLE 3.4.3 SFA-5.9/SFA-5.9M: A-NUMBERS AND F-NUMBERS OF BARE STAINLESS STEEL
ELECTRODES AND RODS
(UNS S20910), which is listed in ASME Material Specifications
SA-182, SA-240, SA-249, SA-312, SA-358, SA-403, SA-479,
SA-813, and SA-814. ER218 is designed for welding type UNS
S21800 that is listed in ASME Material Specifications SA-240
and SA-479. ER219 is typically used for welding UNS S21900.
ER240 can be used for welding type XM-29 (UNS S24000),
which is list ed in ASME Material Specifications SA-240,
SA-249, SA-312, SA-358, SA-479, SA-688, SA-813, and SA-814.
Nitrogen- strengthened, austenitic stainless steels are grouped as
P-No. 8, Group 3 in QW/QB-422 of Section IX.
3.4.4.11.2 Austenitic Stainless Steel Electrodes and Rods.
The ER308-grouped filler metals have wide use in the welding of
Types 304 stainless steels, which are grouped as P-No. 8 in QW/
QB-422 in Section IX. P-No. 8 base metals are listed in ASME
Material Specifications SA-182, SA-213, SA-240, SA-249,
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-61
TABLE 3.4.3 SFA-5.9/SFA-5.9M: A-NUMBERS AND F-NUMBERS OF BARE STAINLESS STEEL
ELECTRODES AND RODS (CONT’D)
SA-312, SA-336, SA-358, SA-376, SA-403, SA-409, SA-430,
SA-479, SA-666, SA-688, SA-813, and SA-814. Type 304 (UNS
S30400) or Type 304L (UNS S30403) are the most common stainless steels welded with either ER308 or ER308L. The “L” grades
are generally selected for improved corrosion resistance because
the 0.03% maximum carbon content of weld metal deposited by
ER308L reduces the possibility of intergranular carbide precipitation. Because of the chemistry overlap, an ER308 could also be
certified as ER308H.
The ER309 series of filler metals contains more chromium and
nickel than the ER308 types. These filler metals are used to weld
base metals such as UNS S30900, S30908, S30909, S30940, and
S30941. Base metals of these compositions are generally listed in
the same ASME Material Specifications as UNS S30400. Both
ER309 and ER309L are commonly used for applying the first
layer of corrosion-resistant stainless-steel overly. The remaining
layers are typically deposited with ER308 or ER308L. Because of
their richer chemical composition, electrodes in this group are also
good for joining dissimilar metals, such as Type 304 stainless steel
joined to carbon or low-alloy steel.
Filler metals in the ER316 grouping are generally used for welding base metals of like designations (316, 316L, etc.) Molybdenum
strengthens these stainless steels and provides creep resistance at
elevated temperatures. Type 316 base metals are typically listed in
the same ASME Material Specifications as UNS S30400.
The ER347 filler metals are stabilized with columbium
(niobium) or columbium (niobium) plus tantalum to reduce the
possibility of intergranular chromium carbide precipitation for
3-62 t Chapter 3
increased corrosion resistance. These filler metals are usually used
for welding stainless steels of similar composition that have been
stabilized with columbium (niobium) or titanium, such as Type
347 (UNS S34700). Type 347 stainless steels are grouped as P-No.
8 in QW/QB-422 of Section IX and are listed in the same ASME
Material Specifications as UNS S34700.
The ER308, ER309, ER316, and ER347 grouping of filler metals
in this specification also have grades that contain increased silicon to improve the usability of these electrodes with GMAW. The
classifications with silicon end with the elemental symbol “Si.”
The ER3556 weld deposits are resistant to high-temperature
corrosive environments containing sulfur. This filler metal is typically used to join UNS R30556 in ASME Material Specifications
SB-435, SB-572, SB-619, SB-622, and SB-626. These base metals
are grouped as P-No. 45 in the nonferrous QW/QB-422 P-number
tables of Section IX.
3.4.4.11.3 Martensitic Stainless Steel Electrodes and Rods.
The ER410 filler metals deposit a martensitic, 12% chromium
(12Cr) alloy weld. Preheat and postweld heat treatments are
generally recommended. These electrodes could be used to weld
UNS S41000 or S41008, listed in ASME Material Specifications
SA-240, SA-268, and SA-479. E410NiMo is typically used for
welding castings such as Type CA6NM, listed in ASME Material
Specification SA-487.
3.4.4.11.4 Ferritic Stainless Steel Electrodes and Rods. The
ER430 filler metals usually require both preheat and postweld heat
treatment to obtain optimum mechanical properties and corrosion
resistance. P-No. 7 base metals, Types 405 (UNS S40500) and 430
(UNS S43000) listed in ASME Material Specifications SA-240,
SA-268, and SA-479, can be welded with these filler metals.
3.4.4.11.5 Duplex Stainless Steel Electrodes and Rods. The
ER2209, ER2553 and ER 2594 filler metals deposit duplex
stainless-steel weld metal having an austenitic-ferritic (duplex)
microstructure. ER2209 is used primarily to weld duplex stainless
steels such as UNS S31803, listed in ASME Material Specification
SA-240. UNS S31803 is grouped as P-No. 10H, Group 1 in QW/
QB-422 of Section IX. E2553 is primarily used to weld duplex
stainless steels containing approximately 25% chromium. ER2594
is used to weld super duplex stainless steels with a PREN of at least
40.
3.4.4.12 SFA-5.10/SFA-5.10M: Specification for Bare
Aluminum and Aluminum Alloy Welding Electrodes and Rods
Bare aluminum and aluminum alloy electrodes and rods produced
to this specification are for use with gas-shielded processes such
as GMAW, GTAW, PAW, and OFW. As with the other bare filler
metals, the letters “ER” in the designation indicate that the wire
can be used either as an electrode or as welding rod. Filler metals
become electrodes with the GMAW process; welding rods with
GTAW, PAW, and OFW. The remaining numerical portion of the
classification is based on the Aluminum Association’s [8] alloy
designation identifying the alloy type rather than tensile strength
and usability. In general, aluminum and aluminum-base alloys
are grouped as P-Nos. 21, 22, 23, 25, and 26 in QW/QB-422 of
Section IX. The welding materials are grouped as F-Nos. 21, 22,
23, 24, and 25 in QW-432.
Typically, ER1100 (F-No. 21) filler metal can be used to weld
UNS A91100 and UNS A93003 (P-No. 21) base metals listed in
ASME Material Specifications SB-209, SB-221, and SB-241. Both
UNS A95052 and UNS A95652 are in the same Material Specifications, but are grouped as P-No. 22. These two aluminum alloys
are commonly welded with ER5654 (F-No. 22).
One of the most commonly welded aluminum alloys is UNS
A96061 (Type 6061), which is grouped as P-No. 23 in QW/QB422. It is typically welded with ER4043 (F-No. 23), although other
fillers are suitable. Type 6061 is listed in ASME Material Specifications SB-209, SB-210, SB-211, SB-221, SB-234, SB-241, SB247, and SB-308.
UNS A95083 base metal is grouped as P-No 25; it is listed in
ASME Material Specifications SB-209, SB-221, SB-241, and SB247. ER5183 (F-No. 22) is typically used to join this material. The
welding rods R-A356.0, R206.0, R-C355.0, R357.0, and R-A357.0,
grouped as F-No. 24 in QW-432, are designed for repair or of castings of comparable chemical composition. Finally, ER2319 and
ER2060 are the only filler metals listed as F-No. 25 in QW/QB422. ER 2319 is intended for welding aluminum alloy 2219 that is
not assigned a P-Number.
Many of the filler metals listed in this specification can be
used on multiple aluminum and aluminum alloys. Guides for the
selection and use of aluminum and aluminum-alloy filler metals
are in numerous publications, including those available from the
AWS and ASTM.
3.4.4.13 SFA-5.11/SFA-5.11M: Specification for Nickel and
Nickel Alloy Welding Electrodes for SMAW Covered electrodes manufactured to this specification are used for depositing
nickel and nickel alloy weld metal with SMAW. Weld metal
deposited by these electrodes has a nickel content greater than that
of any other element. Nickel-base alloys for welding cast iron are
not in this specification; they are classified in SFA-5.15. Electrodes
in SFA-5.11/SFA-5.11M have a wide range of uses for cryogenic
service, corrosion-resistant, and oxidation-resistant applications in
the fabrication of ASME pressure vessels and piping.
Nickel and nickel alloy electrode classifications begin with
the letter “E,” followed by the symbol for nickel (“Ni”) to
represent the primary element. This symbol is then followed by
the remaining principal elements, such as Cr, Mo, Cu, Co, and Fe.
When the principal elements are identical, a numerical designator
is added at the end of the classification. Like most stainless steel
and nonferrous electrodes, this classification represents the type
of nickel alloy rather than the tensile strength. Therefore, an
ENiCrFe-3 classification is a nickel alloy electrode containing
chromium and iron. It is also the third (-3) of many ERNiCrFe
designations. Figure 3.4.5 illustrates a typical nickel welding
electrode classification.
Nickel-base electrodes are assigned as F-Nos. 41–46 in QW-432
of Section IX for procedure and performance qualification. These
electrodes are used for welding nickel and nickel-base alloys listed
as P-Nos. 41–49 in QW/QB–422. A-Numbers are not assigned
in QW-442 for nickel-base electrodes because the weld deposit
is nonferrous.
When nickel-base alloys are welded, cleanliness is imperative.
Low-melting-point contaminants, such as sulfur, lead, and silver,
may cause embrittlement and subsequent cracking of the base
metal or weld during heating or welding. In addition to joining
metals of comparable composition, these electrodes are commonly
used for welding dissimilar base metals and also for clad overlay.
In either case, it is important to use welding techniques that minimize dilution of the weld deposit by the base metal.
The following text includes general descriptions of some
electrode types and the applications for them. Other than the
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-63
FIG. 3.4.5 SFA-5.11/SFA-5.11M: TYPICAL SMAW NICKEL
WELDING ELECTRODE CLASSIFICATION
classifications for welding 9% nickel steels, most of these electrode classifications can also be used for corrosion resistant overlay (cladding), surfacing, and welding nickel-base alloys to steel.
The ENi-1 classified electrodes are predominantly nickel and
are typically used to join base metals such as UNS N02200 or
N02201, listed in ASME Material Specifications SB-160, SB-161,
SB-162, SB-163, and SB-366. ENiCr-4 is used primarily to weld
cast ASTM A 560.
The ENiCu-7 electrodes are typically used for welding nickelcopper alloys, for welding nickel-copper alloys to steel, and for
corrosion resistant overlay (cladding) of steel. Base metals of UNS
N04400, listed in ASME Material Specifications SB-127, SB-163,
SB-164, SB-165, SB-366, and SB-564, can be welded with these
electrodes.
The ENiCrFe-1, ENiCrFe-2, and ENiCrFe-3 electrodes can be
used to join UNS N06600 base metal, listed in ASME Material
Specifications SB-163, SB-166, SB-167, SB-168, SB-366, SB516, SB-517, and SB-564.
The ENiCrFe-4, ENiCrFe-9, and ENiCrFe-10 electrodes are
typically used for welding 9% nickel steel, grouped as P-No. 11 A,
Group 1 in QW/QB-422 of Section IX. The 9% nickel-steel-base
metal (UNS K81340) is listed in ASME Material Specifications
SA-333, SA-334, SA-420, SA-353, SA-522, and SA-553. ENiCrMo-4, ENiMo-8 and ENiMo-9 electrodes can also be used for
welding 9% nickel steel.
The ENiCrFe-7 electrodes can be used for welding the nickel–
chromium–iron alloy (UNS N06690), listed in ASME Material
Specifications SB-163, SB-166, SB-167, SB-168, and SB-564.
The ENiCrFe-12 electrode is used for welding base metals designated as UNS N06025 and the ENiCrFeSi-1 electrode is used to
weld base metals designated as UNS N06045.
The ENiMo-1 electrodes can be used for welding nickelmolybdenum alloys to steel and to other nickel-base alloys.
Nickel-molybdenum base metal (UNS N10001) is listed in ASME
Material Specifications SB-333, SB-335, SB-619, SB-622, and
SB-B626. Another Ni–Mo electrode (ENiMo-3) is typically used
for welding dissimilar metal combinations of nickel-base, cobaltbase, and iron-base alloys.
The ENiMo-7 electrodes have controlled low levels of
carbon, iron, and cobalt. They are typically used to weld nickelmolybdenum alloy (UNS N10665), listed in ASME Material Specifications SB-333, SB-335, SB-619, SB-622, and SB-B626.
ENiMo-8 and ENiMo-9 are used for welding 9 percent
nickel Steel.
The ENiMo-10 electrodes can be used for welding UNS N10665
and N10675 base metals, listed in ASME Material Specifications
SB-333, SB-335, SB-619, SB-622, and SB-626.
The ENiCrCoMo-1 electrodes can be used for welding nickel–
chromium–cobalt-molybdenum alloy (UNS N06617), listed in
ASME Material Specifications SB-166 and SB-564.
The ENiCrMo-l electrodes can be used for welding nickel–
chromium–molybdenum alloy (UNS N06007), listed in ASME
Material Specifications SB-366, SB-581, SB-582, SB-619, and
SB-622.
The ENiCrMo-3 electrodes are typically used for welding
nickel–chromium–molybdenum alloy (UNS N06625), listed in
ASME Material Specifications SB-366, SB-443, SB-444, SB-446,
SB-564, SB-704, and SB-705.
The ENiCrMo-4 electrodes can be used for welding nickelchromium–molybdenum alloy (UNS N10276), listed in ASME
Material Specifications SB-366, SB-564, SB-574, SB-575, SB-619,
SB-622, and SB-626. The ENiCrMo-4 electrodes represent yet
another classification that can be used for welding 9% nickel steel.
The ENiCrMo-5 electrodes can be used for surfacing steel clad
with a nickel-chromium-molybdenum alloy.
The ENiCrMo-6 electrodes represent yet another classification
that can be used for welding 9% nickel steel. The 9% nickel-steelbase metal (UNS K81340) is listed in ASME Material Specifications SA-333, SA-334, SA-420, SA-353, SA-522, and SA-553.
The ENiCrMo-7 electrodes can be used for welding nickelchromium–molybdenum alloy (UNS N06455), listed in ASME
Material Specifications SB-366, SB-574, SB-619, SB-622, and
SB-626.
The ENiCrMo-9 electrodes can be used for welding nickelchromium-molybdenum alloy (UNS N06985), listed in ASME
Material Specifications SB-366, SB-581, SB-582, SB-619, SB622, and SB-626.
The ENiCrMo-10 electrodes can be used for welding nickelchromium-molybdenum alloy (UNS N06022), listed in ASME
Material Specifications SB-366, SB-564, SB-574, SB-575, SB619, SB-622, and SB-626. This electrode may also be used as a
substitute for ENiCrMo-3, depending on the service conditions.
The ENiCrMo-11 electrodes can be used for welding nickelchromium-molybdenum alloy (UNS N06030), listed in ASME
Material Specifications SB-366, SB-581, SB-582, SB-619, SB622, and SB-626.
The ENiCrMo-12 electrodes are typically used for welding
chromium–nickel–molybdenum austenitic stainless steels to themselves, to duplex stainless steels, to nickel–chromium–molybdenum
alloys, and to steel. The ENiCrMo-12 composition is balanced to
provide corrosion resistant welds for use at temperatures below
the creep range of highly alloyed austenitic stainless steels. UNS
S31254 is one alloy that can be welded with these electrodes; it is
listed in ASME Material Specifications SA-182, SA-240, SA-249,
SA-312, SA-358, SA-403, SA-409, SA-479, SA-813, and SA-814.
The ENiCrMo-13 electrodes can be used for welding nickel–
chromium–molybdenum alloy (UNS N06059), listed in ASME
Material Specifications SB-366, SB-564, SB-574, SB-575, SB619, SB-622, and SB-626.
The ENiCrMo-14 electrodes can be used to weld nickel–
chromium-molybdenum alloys such as UNS N06686, N06625,
N10276, and N06022. UNS N06625 is listed in ASME Material
Specifications SB-366, SB-443, SB-444, SB-446, SB-564, SB704, and SB-705, whereas both UNS N10276 and N06022 are in
listed in SB-366, SB-564, SB-574, SB-575, SB-619, SB-622, and
SB-626.
Electrodes, ENiCrMo-17, -18, and -19 have been added to A
5.11. ENiCrMo-17 is used for welding UNS N06200 base metals
ENiCrMo-18 is used to weld UNS N06625 base metals, but can
3-64 t Chapter 3
be used for N06625, N08825, N06985, N08020, N08926 and
N08031. ENiCrMo-19 is used to weld UNS N06058 base metals.
Other additions include ENiCrCoMo-1 and ENiCrWMo-1.
ENiCrCoMo-1 is used to weld UNS N06617 base metal and
ENiCrWMo-1 is used to weld UNS N06230 basemetal.
3.4.4.14 SFA-5.12/SFA-5.12M: Specification for Bare
Tungsten and Tungsten Alloy Electrodes for Arc Welding
and Cutting This specification includes the requirements for bare
tungsten and tungsten alloy electrodes used for welding and cutting with GTAW and PAW. Tungsten electrodes are not consumed
during welding or cutting; they are instead used to establish the
electric arc. The classification starts with the letter “E” for electrode and is followed by the symbol “W” for tungsten. Either the
letter “P” for pure or the type of oxide alloyed with the tungsten
follows the “W” designator. The remaining number designator
indicates the percent of oxide. For example, the classification
EWTh-2 is an electrode (E) that is made of tungsten (W) having
a thorium oxide or thoria (Th) content of 2% (–2). Tungsten electrodes designated as EWTh-2 used to be the most prevalent and
are commonly referred to as 2% thoriated tungsten electrodes.
Other oxides such as cerium and lanthanum are gaining favor for
tungsten electrodes.
3.4.4.15 SFA-5.13: Specification for Solid Surfacing
Welding Rods and Electrodes This specification includes the
requirements for bare electrodes, rods, and covered electrodes
used for surfacing. Bare electrodes and rods are used for surfacing
with GTAW and GMAW; covered electrodes are used for surfacing with SMAW. The bare filler metals are classified in the solid
or product form based on the manufactured chemical composition;
covered electrodes are classified based on the chemical composition of their undiluted weld metal. Most of the welding materials
in this specification are used in hard-facing applications for abrasion, wear, or galling resistance. Many also produce weld deposits
that provide corrosion and oxidation resistance.
3.4.4.16 SFA-5.14/SFA-5.14M: Specification for Nickel
and Nickel-Alloy Bare Welding Electrodes and Rods This
specification gives the requirements for classifying bare nickel and
nickel-base alloy welding electrodes, strip electrodes, and welding
rods for use in GTAW, GMAW, PAW, and SAW with flux. Weld
metal deposits from these electrodes have a nickel content that
is greater than that of any other element. Nickel-base electrodes
and rods follow the same basic classification system as the nickel
and nickel alloy covered electrodes in SFA-5.11/SFA-5.11M.
These electrodes are used in ASME Code fabrication for a wide
range of cryogenic service, corrosion- resistant, and oxidationresistant applications.
Nickel-base welding electrodes and rods are assigned F-Nos.
41–46 in QW-432 of Section IX for procedure and performance
qualification. These filler metals are used for welding nickel and
nickel-base alloys listed as P-Nos. 41–49 in QW/QB-422. Since
nickel-base electrodes deposit nonferrous weld metal, A-Numbers
of QW-442 are not applicable.
When nickel-base alloys are welded, cleanliness is imperative. Low-melting-point contaminants, such as sulfur, lead, and
silver, may cause embrittlement and subsequent cracking of the
base metal or weld during heating or welding. These electrodes
and filler metals are commonly used for welding dissimilar base
metals and for clad overlay. In either case, it is important to use
welding techniques that minimize dilution of the weld deposit by
the base metal.
Most SFA-5.14/SFA-5.14M electrodes and rods have comparable classifications in SFA-5.11/SFA-5.11M. The following
text gives some general descriptions of the electrodes and rods in
this specification.
The ERNiCr-3, ERNiCr-6, and ERNiCrFe-5 filler metals can
be used to join UNS N06600 base metal, listed in ASME Material
Specifications SB-163, SB-166, SB-167, SB-168, SB-366, SB516, SB-517, and SB-564. The selection of the filler metal depends
on the particular application.
Both ERNiCr-7 and ERNiCr-7A filler metals were developed
for welding alloy 690 (UNS N06690) that is listed in material specifications SB-163, SB-167, and SB-168. Previously, ERNiCr-3
may have been used to weld alloy 690 components.
The ERNiFeCr-1 filler metal is typically used to weld UNS
N08825 base metal, listed in ASME Material Specifications
SB-163, SB-366, SB-423, SB-424, SB-425, SB-704, and SB-705.
ERNiFeCr-2 filler metal can be used to join UNS N07718 base
metal listed in ASTM B-637.
The ERNiMo-2 filler metals can be used for welding nickelmolybdenum base metal (UNS N10003), listed in ASME Material
Specifications SB-366, SB-434, and SB-573. ERNiMo-3 filler
metal is used for welding dissimilar metal combinations of nickelbase, cobalt-base, and iron-base alloys.
The ERNiCrWMo-1 filler metal is generally used for welding nickel–chromium–cobalt-molybdenum alloy (UNS N06230),
listed in ASME Material Specifications SB-366, SB-435, SB-564,
SB-572, SB-619, SB-622, and SB-626.
The ERNiCrMo-7 filler metal is intended for welding nickel–
chromium–molybdenum alloy (UNS N06455), listed in ASME
Material Specifications SB-366, SB-574, SB-619, SB-622, and
SB-626.
The ERNiCrMo-3 electrodes are typically used for welding
nickel–chromium–molybdenum alloy (UNS N06625), listed in
ASME Material Specifications SB-366, SB-443, SB-444, SB-446,
SB-564, SB-704, and SB-705.
The ERNiCrMo-4 electrodes can be used for welding nickelchromium–molybdenum alloy (UNS N10276), listed in ASME
Material Specifications SB-366, SB-564, SB-574, SB-575, SB619, SB-622, and SB-626. The ERNiCrMo-4 electrodes can be
used for welding 9% nickel steel.
3.4.4.17 SFA-5.15: Specification for Cast Iron Welding
Rods and Electrodes This specification includes the requirement for bare electrodes and rods, covered electrodes, and flux
cored electrodes used for cast iron welding. It is one of the few
specifications that include all the welding material product forms
in one location. Bare wire is either used as a rod for OFW or as
an electrode for GMAW, flux-cored electrodes (metal powder
and flux within a metal sheath) are used for flux cored arc welding (FCAW), and the covered electrodes are used for SMAW.
Materials in this specification are intended for welding or welding
repair of gray, malleable, nodular, compacted-graphite, and some
alloy-type cast irons. Welding materials classified in this specification have limited (if any) ASME Code applications.
3.4.4.18 SFA-5.16/SFA-5.16M: Specification for Titanium
and Titanium Alloy Welding Electrodes and Rods This specification defines the requirements for classifying titanium and
titanium alloy electrodes and rods for GTAW, GMAW, and PAW.
Titanium and titanium alloy filler metals are classified based on
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-65
their chemical composition, which is determined by filler metal
analysis or analysis of the stock from which the filler metal is
made.
The chemical symbol for titanium (Ti) follows the letters
“ER” in the classification to identify the filler metal as titanium
or a titanium-base alloy. The numeral portion of the designation
identifies the chemical composition. Therefore, the classification
ERTi-9 is a bare wire electrode or rod (ER) that is titanium based
(Ti) and contains a nominal alloying content of 3% aluminum and
2.5% vanadium (–9). The letters “ELI” may appear at the end of
the classification, indicating that the filler metal is produced to
meet with extra-low content of interstitial elements (i.e., carbon,
oxygen, hydrogen, and nitrogen).
Titanium is a reactive metal and is sensitive to embrittlement
by oxygen, nitrogen, and hydrogen. A good protective atmosphere is therefore required during welding, which can be provided by high purity inert gas shielding in air or in a chamber, or
by welding in a vacuum. Filler metal is usually matched to the
chemical composition of the base metal to which it is joined. For
increased joint ductility, unalloyed or pure titanium filler metal
may be used.
In 2004, A 5.16 was revised to adjust interstitial chemistry
ranges of the titanium filler metals to ensure the required mechanical properties were met. This included designating a range for
oxygen for all alloys instead of a maximum oxygen content. Additionally, eighteen new filler metal compositions were classified. In
2007, A 5.16 was again revised to include five new classifications.
ERTi-9 and ERTi-9ELI were also combined into the ERTi-9 classification, because ERTi-9 is now classified with lower interstitial
limits. The lower interstitial content filler metal is required to weld
Grade 9 titanium alloys.
Titanium welding materials are assigned F-Nos. 51, 52, 53, 54,
55 and 56 in QW-432 of Section IX, and titanium and titanium
alloy base metals are grouped as P-Nos. 51, 52, and 53 in QW/QB422. The ASME Material Specifications for the various grades are
SB-265, SB-338, SB-348, SB-363, SB-381, SB-861, and SB-862.
The text that follows describes some titanium and titanium alloy
electrodes and rods.
The ERTi-1, ERTi-2, ERTi-3, and ERTi-4 filler metals are commonly referred to as commercially pure (CP) titanium or unalloyed
titanium. Commercially pure Grade 2, UNS R50400 is the most
widely used titanium alloy for industrial applications because of
its good balance of strength, formability, and weldability. UNS
R50400 base metal is grouped as P-No. 51 in QW/QB-422 and can
typically be welded with these filler metals.
The ERTi-5 filler metal has a nominal composition that includes
6% aluminum and 4% vanadium (6–4 titanium). The 6–4 titanium
alloys have both high strength and excellent fatigue strength, and
they are heat-treatable as well as readily weldable. ERTi-5ELI
filler metal is the extra-low interstitial (ELI) version of ERTi-5
that is used in applications requiring high fracture toughness.
3.4.4.19 SFA-5.17/SFA-5.17M: Specifications for Carbon
Steel Electrodes and Fluxes for SAW This specification contains the requirements for carbon steel electrodes and fluxes for
SAW. Both solid and composite (cored-wire) electrodes are classified. This specification differs from other carbon steel electrode
specifications in that the solid and composite wires are classified
by chemical composition and by mechanical properties with a
particular flux.
The classification system for electrodes in SFA-5.17/SFA5.17M is more complex than for covered electrodes because a flux
FIG. 3.4.6 SFA-5.17/SFA-5.17M: TYPICAL SAW CARBONSTEEL FLUX CLASSIFICATION (See Figure 1M in SFA-5.17M
for metric designation)
actually dictates the classification. Figure 3.4.6 illustrates a typical
carbon steel SAW-flux classification. As with the other carbon
steel covered and low alloy steel covered electrodes in SFA-5.1/
SFA-5.1M, it is the strength and chemical composition that determines most of the flux classification.
A flux can be used in many classifications. The number of flux
classifications is limited only by the number of electrode classifications and the as-welded or postweld heat treated condition. The
container of flux must list at least one classification, although it
may list all the classifications that the flux will meet. For example,
the F7A2-EM12K flux classification may also meet the requirements for F6P4-EM12K, F7A2-EM13K, and F7A4-EH12K.
When carbon steels with the available flux combinations are
welded, both the chemical composition and mechanical properties should be considered. Flux is manufactured by different
methods to produce granular forms of fusible mineral compounds. Fluxes can be described as neutral, active, or alloy—
characteristics that can influence weld metal chemistry and
properties differently.
Neutral fluxes do not produce any significant change in the weld
metal chemical composition with large changes in the arc voltage. Neutral fluxes are used primarily for multipass welding on
thicker base metals (>1 in.). Little or no deoxidizers are provided
by neutral fluxes; therefore, the welding electrode must provide
the deoxidization. If insufficient deoxidation occurs, welds made
on rusty or heavily oxidized steel with these fluxes are susceptible to porosity and centerline cracking. Although it is commonly
3-66 t Chapter 3
referred to as neutral, the weld deposit will not necessarily be the
same as the electrode composition; some slight changes should be
expected. The Wall neutrality number (N) can be used as a measure
of the flux neutrality. A flux classification with an N of 35 or less
is considered a neutral flux.
Active fluxes contain small amounts of manganese or silicon as
deoxidizers to provide improved resistance to porosity and weld
cracking. The primary use for active fluxes is for single-pass welds
on rusty or oxidized carbon steel. Since both manganese and silicon can be combined in the flux, these elements tend to build up
in the weld deposit during multipass welding. As the manganese
or silicon content increases, the strength and hardness of the weld
metal increase, but the toughness decreases.
Alloy fluxes are used with carbon steel electrodes to deposit
alloy steel weld metal. Because alloying is added, these types of
fluxes are more applicable to low alloy steel welding, not carbon
steels.
Crushed slags that are produced by crushing the slag formed
during SAW may also be used as flux. Chemical reactions, electrode influences, and base metal dilution during welding affect the
chemical composition of the crushed flux. If crushed slag is used
as flux, or if it is mixed with new flux to form a blended flux, the
letter “S” must appear in the flux classification. For example, the
classification F7A2-EM12K would change to FS7A2-EM12K to
indicate used flux.
3.4.4.20 SFA-5.18/SFA-5.18M: Specification for Carbon
Steel Electrodes and Rods for Gas Shielded Arc Welding This
specification covers carbon steel welding electrodes and rods for
GMAW, GTAW, and PAW. The filler metal can be composite
stranded or composite metal cored, or it can be produced as a
solid wire or a rod. Electrodes and rods in this specification are
classified based on their chemical composition and mechanical properties. Chemical analysis of the solid or product form
is acceptable for classifying the bare wire; however, the weld
deposit must be analyzed to classify the composite stranded
electrodes and composite metal cored electrodes. Mechanical
properties are determined for all classifications from the weld
metal deposit.
The method for identifying welding materials in this specification is similar to that of other specifications except for designators
for solid versus composite electrodes. The letter “E” designates
a composite electrode; the letters “ER,” a bare wire electrode or
rod. Only the number “70” is used in the classification to designate a minimum tensile strength of 70 ksi (70,000 psi). The letter
following this number is either “S” for solid wire or “C” for composite wire, and the number (−2, −3, etc.) that follows the letter
indicates the chemical composition. Two common electrode classifications are ER70S-2 and ER70S-6. In addition, some composite-stranded and metal-cored electrodes have either a letter “M” or
“C” following the number to indicate the shielding gas used for the
classification.
Although these filler metal classifications can be used with
GTAW and PAW, it is GMAW that accounts for most of the usage
for welding carbon steels. It can be defined by four modes of metal
transfer: spray arc, pulsed arc, globular arc, and short circuiting arc. The advantages and disadvantages of each mode must be
weighed when the GMAW process is selected for an application.
All electrodes classified in this specification can be used on carbon
steels, such as ASME SA-36 and SA-285, Grade C; SA-515, Grade
55; and SA-516, Grade 70, all of which are grouped as P-No. 1 in
QW/QB-422 of Section IX.
3.4.4.21 SFA-5.20/SFA-5.20M: Specification for Carbon
Steel Electrodes for FCAW. This specification contains the
requirements for classifying carbon steel electrodes for FCAW
A flux cored electrode is fabricated by forming steel strips around
granular core ingredients of flux and alloying elements. Electrodes
covered by this specification are classified according to the
as-welded mechanical properties, usability characteristics with a
particular shielding gas, and the positional usability. Depending on
the classification, the electrodes may be suitable for welding either
with or without gas shielding.
The first designator of flux cored electrode classifications is
the letter “E” to denote an electrode. Next is a number (either “6”
or “7”) to designate a minimum required tensile strength of 60 or
70 ksi. A position-usability number (either “0” or “1”) follows
the tensile strength number; a “0” indicates that the electrode is
intended for the flat or horizontal position, whereas a “1” indicates
all positions. All flux cored electrodes contain the letter “T” before
the hyphen to denote that they are flux cored. The remaining designators (numbers “1” – “14” or the letter “G” with or without
“S”) following the hyphen denote electrode usability. A letter “J”
that follows the usability number denotes that the electrode meets
the requirements for improved toughness. Optional designators
may also be added for diffusible hydrogen (e.g., H4, H8, or H16).
Figure 3.4.7 illustrates a typical carbon steel FCAW electrode
classification.
All of the electrodes classified in this specification can be used
for welding carbon steels grouped as P-No. 1 in QW/QB-422 of
Section IX, such as ASME SA-36 and SA-285, Grade C; SA-515,
Grade 55; and SA-516, Grade 70. Each electrode has some differences in the core ingredients to make the chemistry and usability
suitable for each particular application and base metal.
3.4.4.22 SFA-5.21: Specification for Bare Electrodes and
Rods for Surfacing This specification contains the requirements
for bare electrodes and rods used for surfacing. Included are bare
wires in straight lengths and covered composite rods for OFW,
GTAW, and atomic-hydrogen welding (AHW). This specification
also includes welding electrodes for SMAW. Composite electrodes or rods are classified based on the chemical composition of
their undiluted weld deposit. One exception, however, is that the
tungsten-carbide rod or electrode is classified based on the carbon
steel tube and the tungsten-carbide granules—that is, the mesh size
and distribution of the granules with in the carbon-steel tube. The
primary use for most of the welding materials in this specification
FIG. 3.4.7 SFA-5.20: TYPICAL FCAW CARBON STEEL
ELECTRODE CLASSIFICATION (See Figure 1 in SFA-5.20M
for metric designation.)
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-67
is in hard-facing or surfacing applications for abrasion, wear,
or galling resistance, with impact resistance varying from light
to heavy.
3.4.4.23 SFA-5.22/SFA-5.22M: Specification for Stainless
Steel Flux Cored and Metal Cored Welding Electrodes and
Rods This specification contains the requirements for stainless steel electrodes for FCAW and flux cored rods for GTAW.
Classifications are similar to those found in SFA-5.4/SFA-5.4M
and SFA-5.9/SFA-5.9M. Electrodes and rods produced to this
specification are commonly used to weld materials grouped as
P-No. 8 in QW/QB-422 of Section IX. Flux cored welding rods
are also included for welding the root pass in stainless steel piping
using GTAW without a purge or backing gas.
As with the stainless steel filler metals classified in SFA-5.4/
SFA-5.4M and SFA-5.9/SFA-5.9M, this classification is based
primarily on chemical composition. Although tensile testing
is required to classify the electrode, the classification does not
include a minimum tensile strength designator. As an example,
the classification E308LT1-1 is defined as an electrode (E) of type
308L chemical composition (308L), with a flux core (T), for all
position (1) welding and classified with CO2 (–1) gas shielding.
Chemical composition is determined by chemical analysis of
undiluted weld deposit. These stainless steel electrodes fall within
the A-Nos. 6–9 composition ranges in QW-442 of Section IX for
welding procedure qualification. All flux cored electrodes in this
specification are designated F-No. 6 in QW-432 for welding procedure and performance qualification.
Ferrite in the weld deposit is an important factor when welding
is done with stainless steel flux cored electrodes, just as it is for
other types of stainless steel welding materials. Ferrite in the weld
deposit reduces the tendency for hot-cracking and also strengthens
the final weld. Although ferrite is not present in all classifications in
this specification, it is especially beneficial when highly restrained
joints or heavy sections are welded. Some slight ferrite variations
in the deposit can be expected when the same flux cored electrode
is used with different shielding gases or welding techniques.
Ferrite determination is not required to classify electrodes in this
specification. However, the purchaser may impose ferrite controls
when ordering electrodes to ensure sound welds for the selected
welding procedure and application. As explained in the discussion of SFA-5.4/SFA-5.4M, ferrite can be determined by chemical
analysis of the undiluted weld deposit or it can be measured with
various magnetic instruments.
Varieties of stainless steel flux cored electrodes are classified in
this specification for welding the different types of stainless steel
base metals available for ASME Code fabrication. Discussed in
the following text are the various groups of flux cored electrodes.
3.4.4.23.1 Austenitic Stainless Steel Flux Cored Electrodes. The
E308TX-X flux cored electrodes are used extensively for welding
the Type 304 series stainless steels. Type 304 (UNS S30400) or
Type 304L (UNS S30403) stainless steels can be welded with either
E308TX-X or E308LTX-X, respectively. These two P-No. 8 base
metals are listed in ASME Material Specifications SA-182, SA-213,
SA-240, SA-249, SA-312, SA-336, SA-358, SA-376, SA-403,
SA-409, SA-430, SA-479, SA-666, SA-688, SA-813, andSA-814.
The “L” grades are generally selected for improved corrosion resistance because the maximum 0.04% carbon content of weld metal
reduces the possibility of intergranular carbide precipitation.
The E309TX-X flux cored electrodes contains more chromium
and nickel than the Type 308 series. Flux cored electrodes in this
group are used to weld base metals of similar compositions, such
as UNS S30900, S30908, S30909, S30940, and S30941. Base
metals of these compositions are generally listed in the same
ASME Material Specifications as UNS S30400. Both E309TX-X
and E309LTX-X are commonly used for applying the first layer
of stainless steel corrosion-resistant overly; E308TX-X or
E308LTX-X are typically deposited with the remaining layers.
Because of their richer chemical composition, electrodes in this
group are also well-suited for joining dissimilar metals, such as
Type 304 stainless steel, to carbon or low-alloy steel. Other types
of E309 electrodes are included in specification for special service
conditions.
The E310TX-X flux cored electrodes are used to weld highalloy heat and corrosion resistant stainless steels of similar composition, such as UNS S31000. These base metals are listed in ASME
Material Specifications SA-182, SA-336, and SA-403. Welds
deposited by E310TX-X are fully austenitic.
The E312TX-X flux cored electrodes are high in chromium; the
resulting weld deposit is high in ferrite. These electrodes are good
choices for dissimilar metal welding because the welds are highly
resistant to weld metal cracking.
The EX316TX-X flux cored electrodes are generally used for
welding base metals of like designations, such as 316 and 316L.
Molybdenum strengthens these stainless steels and provides creep
resistance at elevated temperatures. Type 316 base metals are typically listed in the same ASME Material Specifications as UNS
S30400. E317LTX-X flux cored electrodes deposit weld metal
with a slightly higher alloy content than type EX316 for improved
resistance to crevice and pitting corrosion.
The E347TX-X flux cored electrodes have columbium (niobium)
added as a stabilizer. Type 347 stainless steels are known as the
stabilized grades. Columbium (niobium) reduces the possibility of intergranular chromium carbide precipitation for increased
intergranular corrosion resistance. If tantalum is present, it provides similar results.
These electrodes are usually used for welding stainless steels
of similar composition that have been stabilized with columbium
(niobium) or titanium, such as Type 347 stainless steel (UNS
S34700). Type 347, P-No. 8 base metal is listed in the same ASME
Material Specifications as UNS S30400.
Where these wires are specified for use in high temperature
service, bismuth (Bi) is limited to < 0.002 wt. %.
3.4.4.23.2 Ferritic Stainless Steel Flux Cored Electrodes.
The E409TX-X and E409NbTX-X flux-cored electrodes produce
ferritic stainless steel weld deposits and are typically used for
joining 12% chromium alloys. E430TX-X and E430NbTX-X flux
cored electrodes are also ferritic and are used for similar applications. Welding ferritic stainless steels usually requires both preheat and postweld heat treatment to obtain optimum mechanical
properties and corrosion resistance. P-No. 7 base metal Types 405
(UNS S40500) and 430 (UNS S43000), listed in ASME Material
Specifications SA-240, SA-268, and SA-479, can be welded with
these filler metals.
3.4.4.23.3 Martensitic Stainless Steel Flux Cored Electrodes.
The E410TX-X flux cored electrodes deposit a 12% chromium
(12Cr) martensitic alloy-weld metal. Both preheat and postweld heat treatment are generally recommended. They can be
used to weld alloys such as UNS S41000 or S41008, listed in
ASME Material Specifications SA-240, SA-268, and SA-479.
E410NiMoTX-X is modified to contain less chromium and more
3-68 t Chapter 3
nickel than EX410TX-X. It is used for welding castings such as
Type CA6NM, listed in ASME Material Specification SA-487.
E410NiTiTX-X is modified to contain less chromium but more
nickel than EX410TX-X and contains added titanium as a stabilizer.
3.4.4.23.4 Precipitation-Hardening Stainless Steel Flux
Cored Electrodes. The E630 flux cored electrodes are designed
for welding Type 630 (UNS S17400) precipitation-hardening
stainless and similar steel. The final weldment may be used
as-welded, or welded and precipitation-hardened, or welded,
solution-treated, and precipitation-hardened (depending on the
application). Precipitation-hardening stainless steel materials are
not listed in QW/QB-422 of Section IX.
3.4.4.23.5 Duplex Stainless Steel Flux Cored Electrodes. The
E2209TX-X, E2553TX-X, and E2594TX-X flux cored electrodes
deposit duplex stainless steel weld metal that has an austenitic–
ferritic (duplex) microstructure. E2209TX-X is used primarily to
weld duplex stainless steels such as UNS S31803, listed in ASME
Material Specification SA-240. E2553TX-X and E2594TX-X are
used primarily to weld duplex stainless steels containing approximately 25% chromium.
3.4.4.23.6 Flux Cored Rods for GTAW. The flux cored rods
for GTAW are designed to complete the root pass on a stainless
steel pipe weld without a purge or backing gas. The four rod
classifications are R308LT1-5, R309LT1-5, R316LT1-5, and
R347LT1-5. These rods are typically used for welding the root
pass of base metals with corresponding compositions.
3.4.4.23.7 Metal Cored Electrodes. Metal cored electrodes
that were previously classified in SFA-5.9/SFA-5.9M are now
listed in SFA-5.22/SFA-5.22M. In agreement with worldwide
classification, metal cored electrodes designated as ECXXX are
included in the same specifications as flux cored electrodes.
3.4.4.24 SFA-5.23/SFA-5.23M: Specification for Low-Alloy
Steel Electrodes and Fluxes for SAW This specification contains the requirements for low-alloy steel electrodes and fluxes
for SAW. Both solid and composite (cored-wire) electrodes can
be classified in SFA-5.23. This specification is similar to other
low-alloy steel electrode specifications except that the solid and
composite wires are classified by chemical composition and by
mechanical properties with a particular flux.
The classification system for electrodes follows the same pattern as that used in SFA-5.17/SFA-5.17M for carbon steel SAW
electrodes and fluxes. The main difference is that the chemical
composition of the weld metal from the wire and flux combination
is at the end of the classification. Strength and chemical composition determine most of the lengthy flux classification. If impact or
hydrogen testing is to be part of the classification, additional designators are added. An example of a low-alloy flux classification—
F8A4-ENi4-Ni4—shows that the classification has three distinct
parts: The first, F8A4, indicates the mechanical properties; the
second, ENi4, indicates the wire or electrode chemical composition; and the third, Ni4, indicates the weld deposit chemical composition. In the first part, the letter “F” stands for flux, the number
“8” designates 80 ksi minimum tensile strength, the letter “A” indicates the as-welded condition, and the number “4” indicates a
minimum toughness of 20 ft lb at –40°F.
The second part of the flux classification is a definitive explanation of the chemical composition of the bare electrode. Solid or
bare electrodes are classified based on their chemical composition.
However, composite electrodes (EC) must be used with a particular flux to deposit an undiluted weld pad to determine the chemical composition. In the example, the electrode designation “ENi4”
has the letter “E” to denote electrode as well as the letter–number
combination “Ni4” for an Ni–Mo electrode chemical composition.
The final designator of “–Ni4” indicates the weld deposit will also
be of Ni–Mo chemical composition. It is readily evident for most
low-alloy flux classifications that a redundancy exists between the
electrode chemical composition and the weld-deposit chemical
composition.
A flux can be used in many classifications. The number of flux
classifications is limited only by the number of electrode classifications and the as-welded or postweld heat treatment condition.
The flux container must list one classification, although it may list
all classifications that the flux will meet. For example, the flux
used for the flux classification F7A2-EA2-A2 can also be used to
produce the flux classifications F8A4-ENi4-Ni4 or F10P2-ECF2F2.
When low-alloy steels are welded with the available flux combinations, both the chemical composition and the mechanical
properties should be considered. As discussed in the summary of
SFA-5.17/SFA-5.17M, SAW flux can be described as neutral,
active, or alloy. The main difference between low-alloy steel welding and carbon steel welding is that more alloying elements must
be provided by the electrode when a neutral flux is used. In addition, an alloy flux can be used to obtain the desired weld deposit
chemical composition, in which case the Flux Manufacturer’s recommendations should be followed; changes in the SAW-welding
parameters can greatly influence the deposit chemistry.
The large variety of low-alloy steels requires a selection of
welding materials wider than that of carbon steels. In choosing an
electrode for low-alloy steel SAW, it is important to consider the
alloying elements required to meet the intended properties. Usually an electrode is selected to closely match the composition of
the base metal. However, mechanical properties, such as impacts
and tensile strength with or without postweld heat treatment, also
need to be considered. Additionally, as with carbon steel welding electrodes, the manganese and silicon contents are important in
determining the requirements for single-pass or multipass welds.
A certain minimum manganese content is required to avoid longitudinal centerline cracking, depending on the welding conditions.
Silicon is especially useful as a deoxidizer to reduce porosity in
the weld deposit and to provide good wetting. The following text
discusses the electrode chemical compositions and some specific
electrode applications.
The EA1, EA2, EA3, EA3K, and EA4 (C–Mo steel) electrodes
are similar to many carbon steel electrodes classified as SFA5.17/SFA-5.17M except that ½% molybdenum is added. ASME
Material Specification SA-204, Grade A plate (UNS K11820) and
SA-335, Type P-1 pipe (UNS K11522) are typically welded with
these electrodes. These base metals are grouped as P-No. 3 in QW/
QB-422 of Section IX.
The EB2, EB2H, EB3, EB5, EB6, EB6H, EB8, and EB9 (Cr–
Mo steel) electrodes produce deposits of 1-1/4%–9% chromium
and ½%–1% molybdenum. They are typically used for Section I
high-temperature service power boiler applications. Cr–Mo welding generally requires both preheat and postweld heat treatment.
Base metals that can be welded with these electrodes are grouped
as P-Nos. 4, 5A, 5B, and 5C in QW/QB-422 of Section IX.
The EB9 (9Cr–1Mo–V) is a 9% chromium –1% molybdenum
electrode that is modified with columbium (niobium) and vanadium
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-69
to provide improved creep strength, toughness, fatigue life, oxidation, and corrosion resistance at elevated temperatures. Base metals
of this composition have replaced components made with dissimilar
metals of steel and stainless steel. The 9Cr–1Mo–V (UNS K91560)
steels are listed as P-No. 5B in QW/QB-422 of Section IX; in the
ASME Material Specifications, they are listed as SA-182, SA-199,
SA-213, SA-234, SA-335, SA-336, SA-369, and SA-387.
The ENi, ENi1K, ENi2, and ENi3 (Ni steel) electrodes are produced to have nickel contents with five nominal levels of 1, 2 ½
and 3 ½% nickel. A typical nickel steel is UNS K32018, listed in
ASME Material Specification SA-203 and in QW/QB-422 of Section IX as P-No. 9B, Group 1. Other nickel steels are UNS J31550,
listed in ASME Material Specification SA-352 (P-No. 9B, Group
1), and UNS J41500, in SA-352 (P-No. 9C, Grade 1).
The ENi4, ENi5, EF1, EF2, and EF3 (Ni–Mo steel) electrodes contain ½%–2% nickel and ¼%–½% molybdenum. Typical applications
include the welding of high-strength, low-alloy, or micro-alloyed
structural steels. EF4, EF5, and EF6 (Cr–Ni–Mo steel) electrodes are
used in similar applications. Both groups have good combinations of
strength and toughness. Base metals that can be welded with these
electrodes are grouped as P-No. 11 in QW/QB-422 of Section IX.
The EM2, EM3, and EM4 (high-strength, low-alloy steel) electrodes may contain a combination of chromium, nickel, molybdenum, titanium, zirconium, and aluminum to produce high strength
deposits. They are typically used to weld high yield strength steels
not subject to postweld heat treatment.
The EW (weathering steel) electrodes deposit welds that match
the corrosion resistance and coloring of the ASTM weathering type
structural steels, such as ASTM A242 and A588. As with other
specifications, an EG classification also exists for classifying electrodes to meet specific purchaser or supplier requirements.
3.4.4.25 SFA-5.24/SFA-5.24M: Specification for Zirconium
and Zirconium Alloy Welding Electrodes and Rods This
specification defines the requirements for classifying zirconium
and zirconium-alloy electrodes and rods for GTAW, GMAW, and
PAW. Zirconium and zirconium alloy filler metals are classified
based on chemical composition, which is determined by chemical
analysis of the filler metal or the stock from which the filler metal
is made. Either columbium (niobium) or tin is added as an alloying
element to produce the zirconium alloys.
Because the filler metals are used as both electrodes in GMAW
and rods in GTAW and PAW, the classification starts with the two
letters, “ER.” The chemical symbol for zirconium, “Zr,” follows
the letters to identify the filler metal as zirconium and zirconium
base alloy. The numeral portion of the designation identifies the
chemical composition. Therefore, the classification ERZr3 is a
bare wire electrode or rod (ER) that is zirconium based (Zr) and
contains 1%–2% tin (3) as the nominal alloying content.
Zirconium, like titanium, is a reactive metal; as such, it is sensitive to embrittlement by oxygen, nitrogen, and hydrogen. Therefore, a good protective atmosphere is required during welding,
which can be provided by high-purity-inert-gas shielding in air or
in a chamber or provided by welding in a vacuum. Filler metals
are grouped as F-No. 61 in QW-432 of Section IX and are usually
matched to the chemical composition of the base metal being
joined. Zirconium can also be welded to dissimilar metals of titanium, tantalum, columbium (niobium) and vanadium. Zirconium
and zirconium alloys are grouped as P-Nos. 61 and 62 in QW/
QB-422 of Section IX. Two grades of zirconium, UNS R60702
(P-No. 61) and R60705 (P-No. 62), are listed in ASME Material
Specifications SB-493, SB-523, SB-550, SB-551, and SB-658.
Only three electrodes or rods exist in the zirconium and
zirconium-alloy group. ERZr2 filler metal is a commercially pure
zirconium that deposits a weld metal with good strength and ductility. These electrodes can be used to weld all zirconium alloys.
ERZr3 filler metal has 1%–2% tin as an alloying element and can
be used to weld UNS R60704. ERZr4 filler metal contains columbium (niobium) as an alloying element and is typically used to
weld UNS R60705.
3.4.4.26 SFA-5.25/SFA-5.25M: Specification for Carbon
and Low-Alloy Steel Electrodes and Fluxes for Electroslag
Welding (ESW) The AWS definition of ESW is as follows:
A welding process producing coalescence of metals with
molten slag which melts the filler metal and the surfaces of
the work to be welded. The molten weld pool is shielded by
this slag which moves along the full cross section of the joint
as welding progresses. The process is initiated by an arc which
heats the slag. The arc is then extinguished and the conductive
slag is maintained in a molten condition by its resistance to
electric current passing between the electrode and the work.
SFA-5.25/SFA-5.25M includes all welding materials necessary
for ESW on various types of carbon and low-alloy steels. Included
are the requirements for the classification of both solid and composite metal–cored electrodes and fluxes.
The classification for ESW electrodes, like others, starts with the
letter “E” for electrode. The remainder of the designation is similar to that of SAW materials. For example, FES60-EH14-EW is a
typical flux classification for an ESW. The prefix “FES” indicates an
electroslag flux, the number “60” designates 60 ksi minimum tensile
strength, and the designation “EH 14” is a definitive explanation of
the chemical composition of the bare electrode. The classification
ends with the letters “-EW,” which indicates solid wire. Solid or bare
electrodes are classified based on their chemical composition. Composite electrodes must be used with a particular flux to deposit an
undiluted weld pad for the determination of chemical composition.
A ESW flux can be used in many classifications. Unlike SAW
fluxes, these fluxes are conductive and are specific to ESW. The
number of ESW flux classifications is limited only by the number
of electrode classifications.
SFA-5.25/SFA-5.25M contains carbon steel ESW classifications
EM5K-EW, EM12-EW, EM12K-EW, EM13K-EW, and EM15KEW. The high manganese and low-alloy electrodes are EH14-EW,
EWS-EW, EA3K-EW, EH10K-EW, and EH11K-EW. ES-G-EW is
a general flux classification. The requirements for these electrodes
are usually those to which both the purchaser and the supplier agree.
3.4.4.27 SFA-5.26/SFA-5.26M: Specification for Carbon and
Low-Alloy Steel Electrodes for Electrogas Welding (EGW)
The AWS definition of EGW is as follows:
An arc welding process which produces coalescence of
metals by heating them with an arc between a continuous
filler metal (consumable) electrode and the work. Molding
sheets are used to confine the molten weld metal for vertical
position welding. The electrodes may be either flux cored
or solid. Shielding for use with solid electrodes is obtained
from a gas or gas mixture. Shielding for use with flux cored
electrodes may or may not be obtained from an externally
supplied gas or mixture.
3-70 t Chapter 3
SFA-5.26/SFA-5.26M specifies the requirements for EGW
electrodes for carbon and low-alloy steels. Included are the
classifications of solid wire, flux cored, and metal cored electrodes. Flux cored electrodes are classified as either gas-shielded
or self shielding.
Electrogas electrodes in this specification are classified based on
their chemical composition and mechanical properties. Chemical
analysis of the solid or product form is acceptable for classifying
the bare wire; however, the weld metal deposit must be analyzed
to classify the metal cored or flux cored electrodes. The mechanical properties are determined for all classifications from a weld
metal deposit.
The classification starts with the letters “EG” to designate an
electrogas electrode. A number (6, 7, or 8) follows that designates
a minimum tensile strength of 60, 70, or 80 ksi. The next number or letter designates the impact properties; this is followed by
the letter “T” or “S” to indicate a solid (S) or composite (T) electrode. The classification has a numerical ending that indicates the
chemical composition. Therefore, the classification EG72S-6 is
an electrogas electrode (EG) with a minimum tensile strength of
70 ksi (7) that meets the impact requirement of 20 ft lb at –20°F
(2) and constitutes a solid electrode (S) and a carbon steel with
high manganese content (–6). Electrodes can be also classified
as EGXXS-G, which is a general classification that meets the
requirements to which both the purchaser and the supplier agree.
The electrodes in this specification are similar to the classifications
for GMAW carbon steel electrodes in SFA-5.18/SFA-5.18M.
3.4.4.28.1 Carbon–Molybdenum (C–Mo) Steel Electrodes.
The ER70S-A1, ER80S-D2, ER90S-D2, and E90C-D2 are classifications for carbon steel electrodes with the addition of approximately ½% molybdenum for increased strength, especially at
elevated temperatures. Electrodes with the “-D2” designator contain additional deoxidizers for welding with CO2. ASME Material
Specification SA-204, Grade A plate (UNS K1 1820) and SA-335,
Type P-1 pipe (UNS K1 1522) are typically welded with these
electrodes. These base metals are grouped as P-No. 3 in QW/
QB-422 of Section IX.
3.4.4.28 SFA-5.28/SFA-5.28M: Specification for Low-Alloy
Steel Electrodes and Rods for Gas Shielded Arc Welding
This specification covers low-alloy steel electrodes and rods for
GMAW, GTAW, or PAW. The filler metal can be produced as
solid wire, rod composite stranded, or composite metal cored.
Electrodes produced to this specification are commonly used to
weld low-alloy steels grouped in P-Nos.1, 3, 5, 9, 10, 11 and 15
in Section IX.
Electrodes and rods in this specification are classified based on
their chemical composition and mechanical properties. Chemical
analysis of the solid or product form is acceptable for classifying
the bare wire; however, the weld deposit must be analyzed to classify the composite stranded electrodes and composite metal cored
electrodes. Mechanical properties are determined for all classifications from a weld metal deposit.
The method for identifying welding materials in this specification is similar to that of SFA-5.18/SFA-5.18M. The main difference is that the low-alloy classification ends with number or letter
combinations (e.g., -D2 and -Ni2) to indicate the chemical composition. Figure 3.4.8 illustrates a typical filler metal classification of
low-alloy steel.
Although these filler metal classifications can be used with
GTAW and PAW, it is GMAW that accounts for most of the usage
for welding low-alloy steels. GMAW can be defined by four modes
of metal transfer: spray arc, pulsed arc, globular arc, and short
circuiting arc transfer. Each mode has both advantages and disadvantages that must be considered when one selects the GMAW
process for an application. SFA-5.28/SFA-5.28M contains many
low-alloy steel electrodes of varying chemical composition and
mechanical properties. From these classifications, electrodes can
be selected for the appropriate welding process and procedure to
deposit weld metal that closely matches the chemical composition
and the mechanical properties of the base metal. The following
text gives brief descriptions of low-alloy steel electrodes and rods.
3.4.4.28.2 Chromium–Molybdenum (Cr–Mo) Steel
Electrodes. The ER80S-B2, E80C-B2, ER70S-B2L, E70C-B2L,
ER90S-B3, E90C-B3, ER80S-B3L and E80C-B3L electrodes produce deposits of ½%–2 ¼% chromium and ½%–1% molybdenum.
These electrodes are typically used for Section I power boilers that
are designed for high temperature service. Welding with Cr–Mo
electrodes generally requires both preheat and postweld heat treatment. Base metals that can be welded with these electrodes are
grouped as P-Nos. 4 and 5A in QW/QB-422 of Section IX.
The ER80S-B6 electrodes have a nominal 5% chromium and
½% molybdenum chemical composition and are typically used
for welding Cr–Mo steels, such as the base metals grouped in
P-No. 5B, Group 1 in QW/QB-422 of Section IX. UNS K41545 is
5Cr–½Mo steel and is listed in SA-182, SA-213, SA-234, SA-335,
SA-336, SA-369, and SA-691. Welding with these Cr–Mo electrodes generally requires both preheat and postweld heat treatment.
The ER80S-B8 electrodes have a nominal 9% chromium and
1% molybdenum chemical composition. They are used for welding
Cr–Mo steels such as the base metals grouped in P-No. 5B, Group
1 in QW/QB-422 of Section IX. UNS K81590 is a 9Cr-1Mo steel
listed in ASME Material Specifications SA-199, SA-213, SA-335,
and SA-336. Another similar base metal is UNS K90941, listed
in ASME Material Specifications SA-182, SA-234, and SA-369.
Welding with these Cr-Mo electrodes generally requires both preheat and postweld heat treatment.
The ER90S-B9 (9Cr–1Mo–V) electrodes have 9% chromium
and 1% molybdenum and are modified with columbium (niobium) and vanadium to provide improved creep strength, toughness, fatigue life, oxidation resistance, and corrosion resistance
at elevated temperatures. Base metals with this composition have
replaced many components previously designed with dissimilar
metal combinations of steel and stainless steel. The 9Cr–1Mo–V
(UNS K91560) steels are listed as P-No. 15E in QW/QB-422 of
Section IX. In the ASME Material Specifications, they are listed
FIG. 3.4.8 SFA-5.28/SFA-5.28M: TYPICAL GMAW LOWALLOY STEEL ELECTRODE CLASSIFIC (See Figure A1 in
SFA-5.28M for metric designation.)
COMPANION GUIDE TO THE ASME BOILER & PRESSURE VESSEL CODE t 3-71
as SA-182, SA-199, SA-213, SA-234, SA-335, SA-336, SA-369,
and SA-387.
3.4.4.28.3 Nickel Steel Electrodes. The ER80S-Ni1, E80CNi1, ER80S-Ni2, E80C-Ni2, ER80S-Ni3, and E80C-Ni3 electrodes have nickel contents with three nominal levels of 1, 2 ¼,
and 3 ¼%. They are intended for applications that require good
toughness at low temperatures.
The ER100S-1, ER110S-1, and ER120S-1 electrodes are
designed to weld the high yield strength base metals. Welds made
with these electrodes have excellent toughness at low temperatures.
3.4.4.29 SFA-5.29/SFA-5.29M: Specification for Low-Alloy
Steel Electrodes for FCAW This specification contains the
requirements for classifying low-alloy steel electrodes for FCAW.
Flux cored electrodes are fabricated by forming steel strips
around granular core ingredients of flux and alloying elements.
Classification is based on the as-welded or postweld heat treatment
mechanical properties, usability characteristics with a specific
shielding gas, the positional usability, and the weld metal chemical
composition. Depending on the classification, the electrodes may
be suitable for welding either with or without gas shielding. Flux
cored electrodes produced to this specification are commonly used
to weld low-alloy steels grouped in P-Nos. 1, 3, 5, 9, 10, 11 and
15 in Section IX.
Classifications of low-alloy steel flux cored electrodes follow a
format similar to that used for carbon steel electrodes in SFA-5.20/
SFA-5.20M except that the classification ends with the chemical
composition of the weld deposit. Figure 3.4.9 illustrates a typical low-alloy steel flux cored electrode classification. Another
example—E91T1-K2—can be described as an electrode (E) that
meets a minimum of 90 ksi tensile strength (9), is usable in all
positions (1), is flux cored (T), has certain core characteristics and
usability (1), and is of a nickel steel (-K2) chemical composition.
The following text gives brief descriptions of the low-alloy steel
flux cored electrodes.
3.4.4.29.1 Carbon–Molybdenum (C–Mo) Steel Electrodes.
The EXXTX-A1 flux cored electrodes are carbon steel electrodes
with the addition of ½% molybdenum for increased strength,
especially at elevated temperatures. ASME Material Specification
SA-204, Grade A plate (UNS K11820) and SA-335, Type P-1 pipe
(UNS K11522) are typically welded with these electrodes. These
base metals are grouped as P-No. 3 in QW/QB-422 of Section IX.
3.4.4.29.2 Chromium–Molybdenum (Cr–Mo) Steel
Electrodes. The EXXTX-BX, EXXTX-BXL, and EXXT-BXH
flux cored electrodes produce deposits of ½%–9% chromium and
½%–1% molybdenum. These electrodes are typically used for
Section I power boiler applications that are designed for high temperature service. FCAW with Cr–Mo electrodes generally requires
both preheat and postweld heat treatment. Base metals that can be
welded with these electrodes are grouped as P-Nos. 4, 5A, 5B, 5C
and 15 in QW/QB-422 of Section IX.
3.4.4.29.3 Manganese–Molybdenum (Mn–Mo) Steel
Electrodes. The EXXTX-DX flux cored electrodes deposit welds
with a nominal l ½% manganese and 1/3%–2/3% molybdenum.
These electrodes are designed to match the mechanical properties and corrosion resistance of low-alloy steels, such as ASME
Material Specification SA302, Grade B.
3.4.4.29.4 Nickel–Molybdenum (Ni–Mo) Steel Electrodes. The
EXXTX-K1 flux cored electrodes contain approximately 1% nickel
and ½% molybdenum. Typical applications include the welding
of high strength, low-alloy, or microalloyed structural steels.
3.4.4.29.5 Nickel Steel Electrodes. The EXXTX-NiX and
EXXTX-K7 flux cored electrodes are produced to have nickel
contents with three nominal levels of 1, 2 ¼, and 3 ¼%. Welds
deposited by these electrodes have good notch toughness at low
temperatures. Base metals of these nominal compositions are
listed in ASME Material Specifications SA-203, SA-352 (LC2 and
LC3), and SA-350. Section IX, QW/QB-422 groups these materials in P-No. 9A and 9B. EXXTX-K8 is also a nickel containing
steel alloy that is designed for welding API 5LX80 pipe that is
grouped as S-No 1, Grade 4 in QW/QB-422 of Section IX.
3.4.4.29.6 Other Low-Alloy Steel Electrodes. The EXXTXK2, EXXTX-K3, EXXTX-K4, and EXXTX-K9 flux cored electrodes are designed for welding high yield strength base metal.
Welds made with these electrodes have excellent toughness at low
temperatures.
The EXXTX-K5, EXXTX-K6, EXXTX-WX, and EXXT-G flux
cored electrodes are designed for specific applications. EXXTXK5 is designed to match mechanical properties for AISI 4130 and
8630 steel. Welds in these materials are generally quenched and
tempered after welding. EXXTX-K6 produces welds having high
toughness and lower strength. EXXTX-WX flux cored electrodes
are designed to deposit weld metal that matches the corrosion
resistance and coloring of the weathering type structural steels,
such as ASTM A242 and A588. EXXT-G is a general classification for low-alloy steel flux cored electrodes. The requirements for
these electrodes are usually those to which both the purchaser and
the supplier agree.
FIG. 3.4.9 SFA-5.29/SFA-5.29M: TYPICAL FCAW LOWALLOY STEEL ELECTRODE CLASSIFICATION (See Figure
1 in SFA-5.29M for metric designation.)
3.4.4.30 SFA-5.30: Specification for Consumable Inserts
Consumable inserts are included in this specification based on
design and chemical composition. Standard shapes, styles, and
sizes are specified for use on the root pass when welding is done
with GTAW or PAW. Chemical compositions include carbon
3-72 t Chapter 3
steel, chromium-molybdenum steel, stainless steel, and nickel
alloys. The type and style of insert is based on the particular applications or joint design selected during fabrication.
When consumable inserts for pipe welding are ordered, all details
describing the insert must be specified, including the pipe size
and schedule to be welded. A typical consumable insert ordering
description could be as follows: IN82 consumable insert—Class 1,
Style C—for 2 ½ NPS Schedule 80 pipe. This order designates a
nickel-base (IN82) insert with an inverted T-shaped cross section
(Class 1) and is a preformed ring for an open butt joint (Style C)
that will be used on a 2 7/8 in. diameter pipe with a nominal 0.276
in. wall. Insert material can also be supplied in coil form and shaped
to fit by the User.
3.4.4.31 SFA-5.31: Specification for Fluxes for Brazing and
Braze Welding Fl