lLkepitbitr of 1IL J1)i1qJpillec3
)rofeiloiiri1 ecii1citeoii Qroiiiiicion
Jill i ii ii i
BOARD OF MEChANICAL ENGINEERING
Board Resolution No.
Series of 2007
25
Ai)OI’TION ANt) PROMULGATION OF ‘[lIE REVISED
PI-IILIPPINI( l’IF(lIANhCAI. (.‘()I.)K (2007 FE)I’[ION)
Vb’I—IEREAS, for the practice oI’ niechanical
promulgated the PSM [F Code;
enginecri tie. I he
Hoard adopted and
WhEREAS, there hasteen an urgent and i niportant iced for the updatemenl and
the said Code to cope up with ttic rapid, continuous advancement in
mechanical engineering technology that
has brought about economic rowtli and
development:
revision of
WhEREAS, in lesponse to such need, the PS ME. I TIC., and the other alit late
sectors of the profession have come up with the Revised Philippine Mcclianical Code,
2007 Edition;
WHEREAS, this new Code presents topics with a balanced coverate of relevant
fundamental and realworld practices that would ensure our mechanical engineers to
enhance and maintain high professional, technical, and ethical standards br the practice
of mechanical engineering profession;
WHEREAS, the Board is empowered to adopt and promulgate such (ode
pursuant to its power to adopt a Code of Professional Standards fir the practice o I
mechanical engineering under Sec. 9(h). Art. Ii of R.A. No. 8495. known as the
“Philippine Mechanical Engineering Act of I )98”: a.n(.l
WHEREAS, as part of the Rules and Regulations of the Board, violation of any
provision of this Code is a ground for d iscipi i I1aT’y act on against a pro Icssioiial
mechanical engineer, registered mechanical engineer, and certified plant ineclianic
P. PAREDES ST., CORNER MORAYTA STREET, SAMPALOC, MANILA, PHILIPPINES
P0 BOX 2038, MANILA
//4
;m(I
NOW, THEREFORE, the Board Resol VCS, OS I IS hereby RCSOI ed, In ;lopI
the
by
ted
,
submit
promulgate the Revised Philippine Mechanical Code, 2007 Edition
l paii
Philippine Society of Mechanical Engineers, Inc. (PSM E), ANNEX “A’’, as integra
of the herein Resolution.
This Code shall take effect a fter fifteen (1 5) (lays tbl lowing its lull and complete
in the
publication in the Official Gazette or iii a newspaper I general eiren latini
Philippines.
Done in the City of Manila, this
17
day of October 2007.
ALFRY.
(‘,{inirniaii
7
(VACAN’I’)
PALISBO
M ember
(_,,/‘ rnber
OS G. ALMELOR
Secretary, Professional
Regulatory Boards
A P PRO \/ ED:
LEONOR TRLPON-ROSFRO
Chairperson
4
RUTH RANA PADJ.LLA
Coinmi ssi oner
PRB-MEF]D-SRB
AYP/CGA/ofie
a: revised me code 2007
ROSAS
PHILIPPINE SOCIETY OF MECHANICAL ENGINEERS
INTEGRATED ASSOCIATION OF MECHANICAL ENGINEERS
CODE COMMITTEE 2008
EDUARDO P. MENCIAS
CHAIRMAN
MEMBERS
VICTORINO Z. SIANGHIO, JR.
PACIFICO 0. ORTALIZA
ALBERTO I. LORESCO, JR.
CARMELITO A. ALUNAN
CIPRIANO A. MARCELO
Iiipin
1{publlc of II1i
rnfcrnwf Ruftzfion QIummon
BOARD OF MECHANICAL ENGINEERING
MESSAGE
Most cordial greetings to the Philippine Society of Mechanical Engineers
(PSME) as you publish the Philippine Mechanical Code (M.E. Code) 2008 edi
tion.
This publication is an effective research and resources material, not only for
mechanical engineers but also for those who seek relevant information to guide
the general public on efficiency and quality performance. It sets forth the stan
dards of professional conduct thereby ensuring that if faithfully conforms to the
implementation of Republic Act No. 8495, otherwise known as the “Philippine
Mechanical Engineering Act of 1998”, and provides for the remedial measures
or sanctions for any violation.
This contribution to the society epitomizes your earnest desire to harmonize and
unite all mechanical engineers and provide a guiding path in achieving profes
sional excellence, integrity, humility and service. This worthy project of PSME
will surely mark another milestone of success, as you continue to broaden the
horizon and expand the boundaries of Filipino mechanical engineers.
Congratulations and more power!
LEONOR TRIPON-ROSERO
Secretary
August 1, 2008
P. PAREDES ST., CORNER N. REYES ST., SAMPALOC, MANILA, PHILIPPINES, 1008
P.O. BOX 2038, MANILA
ubItc 1TE t1e Ii14phw
Re
3
1
ruftnrnt Reu{tHøn mmnn
MESSAGE
Warmest greetings and congratulations to the Officers and Members of
the Philippine Society of Mechanical Engineers (PSME) for this tangible
labor of love, the publication of the 2008 Philippine Mechanical Code
(M.E. Code).
The ultimate and grateful beneficiaries of this repository of valuable
information are in the registered and licensed mechanical engineers and the
public, who continue to repose trust and value to the mechanical engineering
profession. May this comprehensive compilation inspire, motivate and
encourage professionals in the vital participation of fulfilling their mandate
and promoting standards of excellence.
It is the dream of many, if not all to become experts in their chosen fields of
endeavor, and this Code is symbolical of the Society’s commitment to make
sure that the professionals remain true to their sworn duty to serve and
contribute to the progress of our nation, and improve quality of life.
Congratulations on this achievement and more power to PSME!
August 1, 2008
RUTH RANA-PADILLA
Commissioner
P. PAREDES ST., CORNER N. REYES ST., SAMPALOC, MANILA, PHILIPPINES, 1008
P.O. BOX 2038, MANILA
Rpub{fc of flue
rufeIunaI Reukthnn !Iommiion
4tnttht
MESSAGE
It gives me great pleasure to congratulate the Philippine Society of
Mechanical Engineers (PSME) for the release and issuance of the
2008 Philippine Mechanical Engineering Code (M.E. Code)
This publication truly demonstrates the desire of bringing together
concepts, strategies, formula, method and approaches which can
serve as useful guide in the practice of the mechanical engineering
profession, given the call of globalization. It also provides a ready
reference for practitioners, allies, partners and clients in understand
ing the exact science of engineering.
I sincerely hope that this persistent effort of providing avenue for
harmonization and unity among your professional sector and in
improving relations with the general public will achieve its purpose.
We, in the Professional Regulation Commission, shall continue to
be your partner in our common goal of leading others to attaining
professional values of excellence and integrity.
4’L
NILO L. ROSAS
Commissioner
August 1, 2008
P. PAREDES ST., CORNER N. REYES ST., SAMPALOC, MANILA, PHILIPPINES, 1008
Rpuhllc uf If tlijpn
roforntt Ruftftnn mmnn
BOARD OF MECHANICAL ENGINEERING
I
MESSAGE
It is with great privilege that I offer my warmest congratulations to the
Philippine Society of Mechanical Engineers (PSME) and its upcoming
publication of the Philippine Mechanical Code (M.E.Code) 2008 edition.
This vital reference book puts together expertise of private practitioners and
various references for mechanical engineers to continuously cope up with
the advancement of technology, formulating and adopting techniques and
systems relevant in the Philippine condition and to constantly uphold the
ideals of integrity, spiritual values, and commitment to serve the nation.
This effort of the men and women of the PSME functions greatly in the
administrative supervision of the Board over its professionals. Your
invaluable role in providing this reference reflects your commitment to
professionalism. I believe that only through this comprehensive information
campaign that we will be able to observe, implement and uphold
professional excellence.
We in the Board of Mechanical Engineering take pride in this successful
collaboration with PSME and in the Society’s effort to update its members
and the general public on the latest developments in the implementation of
the rules and regulations of Republic Act No. 8495, otherwise known as the
Philippine Mechanical Engineering Act. of 1998’. This M.E. Code is a
worthy project that we are pleased to endorse and support. Rest assured that
I join you in all your endeavors to continuously define, articulate and realize
the progressive development of our chosen profession.
My sincerest congratulations and best wishes to all.
ENGR. A FREDO Y. P0
Chairman /
Board of ‘Iechanical Engineering
July 18, 2008
R PAREDES ST., CORNER N. REYES ST., SAMPALOC, MANILA, PHILIPPINES, 1008
P.O. BOX 2038, MANILA
____
PROFESSIONAL REGULATION
Is
MM
C
NJ
0
SI
LEONOR TRIPON-ROSERO
Chairperson
NILO L. ROSAS
Member
RUTH RANA-PADILLA
Member
BOARD OF MECHANICAL
G
N
I
M
E
F?
I
N
G
ENGR. ALFREDO Y. P0
Chairman
1
HON. JOVENCIO C. PALISBO
Member
VACANT
PREFACE 2008 EDITION
This code undertakes a significant change for an advanced study of certain provisions of Mechanical Engineering in the realization of our Global climate change and trends, to address relevant
needs of the future. All PSME Chapters have given their contributions to uplift the standards of our
Code to a more meaningful practice of the Mechanical Engineering Profession.
Our present trend is to venture into a cleaner and greener environmental field. For and in consi
derations of these fields, we adopted the latest revision of the American, European and Japanese
Mechanical Codes which were deemed applicable and relevant to Philippine Conditions, the as
pects of which were clearly defined and illustrated. Moreover, prevailing Philippine conditions has
greatly affected and influenced, with the end in view, such that private practitioners’ inputs were
solicited, reviewed and included in many chapters.
All changes, additions and amendments came about after careful and thorough deliberations and
evaluations by the code committee resulting in simple clarifications and explanations
In case of conflicts in the Interpretation of the provisions of this code, the Board of Mechanical
Engineering, Professional Regulation Commission, shall be the arbiter whose decision shall be
final and unappealable.
The Code and Standards Committee welcomes comments, inputs and suggestions for the improve
ment of this code especially on omissions, errors, conflicts, etc... arising from the final printing of
this code. All suggestions / comments shall then be reviewed and deliberated upon for possible
inclusion in the next edition, as this is a continuing process for evaluation, advancement and prog
ress.
4.
czz
L
/
EDUARDO P. MENCIAS
PSME National President 1979, 1980
Chairman, 2008 Code & Standards Committee
PHILIPPINE SOCIETY OF MECHANICAL ENGINEERS
INTEGRATED ASSOCIATION OF MECHANICAL ENGINEERS
2008 NATIONAL OFFICERS
Saylito M. Purisima
Renato A. Florencio
Reynald B. Ilagan
Antonio Camelo P. Tompar
Julius B. Yballe
Reynaldo P. Uy
Liberato S. Virata
Arlan B. Banquillo
Henry M. Gatilogo
Alberto I. Loresco, Jr
Joel M. Aviso
Cipriano A. Marcelo
Reymundo V. Cruz
Emmanuel C. Tayson
Dean A. Cancino
Roseller 0. Bucoy
Ulysses Rex P. Bonita
Clarito M. Magno
Arnold A. Umbao
Jerico T. Borja
Benjamin C. Zeta
Venerando S. Mesiona, Sr
Joseph Rudente F. David
Manuel C. Espeleta
Vicente B. Vosotros
Celestino P. Cañeca, Jr
President
Executive Vice President
VP-External Affairs
VP-Techical Affairs
VP- Internal Affairs
VP-NCR
VP-Luzon
VP-Visayas
VP-Mindanao
Secretary
Asst. Secretary
Treasurer
Asst. Treasurer
Deputy VP-South Luzon
Deputy VP-NCR
VP-Central Visayas
Deputy VP-Eastern Visayas
Deputy VP-Mindanao
PRO Visayas
Director
Director
Director
Director
Executive Director
Immediate Past President
2008 National President +
FORMER NATIONAL PRESIDENTS:
Tobias P. Marcelo • LuisA. Flores • VictorA. Lim Domingo S. Mendoza, Sr. • Pedro B. Manayon •Adelfo D. Urtula • RodolfoA. Vales • Urbano J.
Pobre • ceferino L. Follosco • Pedro F. Loresco • cesar B. Lopez clodoveo V. Soriano, Jr. • Ernesto B. Marcelo • Pedro Ma. Carino Damaso
c, Tria • Luisito M. Reyes • Roberto G. Abiera . Eduardo P. Mencias •Armando C. Pascual • Julio F. Abarquez •Amaldo P. Baldonado • Victorino
Z. Sianghio, Jr. •Antonio Ro. Herrera • Emesto V. Villanueva • Gemeliano F. calinawan • Danilo 0. Bulanadi •Alfredo Y. Po •Alberto D. Dosayla’
Romeo A. Perlado ‘Augusto c. Soliman • Gerardo c. Hernandez Expedito S. Bollozos Sergio c. Balolong ‘Juan C. Cabanayan Gaudencio
R. de Guzman • Ernesto J. Casis • Roberto A. Lozada • Ramon c. Maniago • Danilo R Hernandez • Vicente V. de Guzman • Edimar V. Salcedo
• Ramon F. Solis * Vicente B. Vosotros
CHAPTER
TABLE OF CONTENTS
PAGE
GENERAL
Scope• Requirements for Permit Application
2
I
Standards for Drawings Inspection
COMMERCIAL AND INDUSTRIAL BUILDINGS
6
Scope• Plant Design Procedure • General Requirements • Machinery & Equipment
Anti-Pollution for Industrial Buildings
3
PRIME MOVERS, POWER TRANSMISSION EQUIPMENT,
MACHINES AND MACHINE PARTS
Scope Definitions • Guards • Principle of Safe Machine Design
System
4
14
Power Transmission
MACHINE GUARDS AND SAFETIES AT POINTS OF
OPERATION AND DANGER ZONES
30
Scope• Definitions • General Requirements. Die-Casting Machines Wood Working
Machine• Paper and Printing Machines • Textiles and Laundry Machinery• Leather and
Composition Goods Machines • Food and Tobacco Machinery. Chemical Industry
Machines • Rubber and Composition Working Machines Stone, Clay and Glass
Working Machines • Cotton and Seed Cotton Processing Machines • Other Industrial
Machinery in Manufacturing Installations • Protection for Electrical Machinery in
Commercial & Industrial Installations • Personal Protection in Workplaces
5
CRANES AND OTHER HOISTING EQUIPMENT
53
Scope. Definitions • General Requirements for Cranes • Boom Type Mobile Cranes
• Hoists • Derricks in Permanent Location • Auxiliary Hoisting Equipment• Operating
Rules• Inspection
6
ELEVATORS, DUMBWAITERS, ESCALATORS AND
MOVING WALKS
63
Scope. Definitions • Electric Elevator • Machine Rooms and Machinery Spaces
Electrical Wiring, Pipes and Ducts in Hoistways and Machine Rooms• Machinery and
Equipment for Electric Elevators • Hydraulic Elevators • Private Residence Elevators
• Hand and Power Dumbwaiters • Escalators• Moving Walks
7
BOILERS AND PRESSURE VESSELS
130
Definitions • General Requirements for Boiler and Pressure Vessel Installation Specific
Requirements for Fired Tube Boilers • Specific Requirements for Miniature Boilers
• Specific Requirements for Low Pressure Heating Boilers • Unfired Pressure Vessels
Test and Inspection • Boiler Inspection • Blow-Offs, Pressure Reduction, Fire Explosion
Devices • Other Testing Methods
8
HEATING, VENTILATING, REFRIGERATING AND
AIR CONDITIONING
Definitions • Air Conditioning and Ventilation Standards • Duct System and Accessories•
Heat Gain Calculations • Refrigeration System • Air Intakes and Outlets • Air Filters
• Noise Abatement • Cold Storage and Refrigeration •Refrigerant Piping, Valves,
Fittings and Related Parts • Pressure Relief Valve • Discharge from Pressure Relief
Devices • Pressure Limiting Devices • Test of Refrigerant Containing Vessels
• Instructions • Helmets • Refrigerant Storage • The Fundamentals in Vapor-Compression
Refrigeration • Anti- Pollution for Ventilating, Refrigeration & Air Conditioning Energy
Conservation for Ventilating, Refrigeration & Air Conditioning • Montreal Protocol
151
173
FIRE PROTECTION AND PREVENTION
9
General Requirements• Indoor General Storage. Fire Protection Systems Outdoor
e
General Storage Anti-Pollution for Standards for Indoor and Outdoor General Storag
Doctrine
Standards on Halon 1301 Fire Extinguished Systems Fire Prevention
10
195
PUMPS
General Requirements Definitions Pumps Fluid Power Metrication • Metric Pump
Formula
11
213
PIPING
Scope Definitions • General Requirements• Identification Colors for Pipes. Fluid Flow
Velocities • Power Piping System Design • Industrial Gas and Air Piping System
• Refrigerator Piping Systems
12
241
METROLOGY
Purpose and Scope. Definitions • Measurement Concepts • Classification of the
Common Measuring Instruments Used in lndustry• Graduated Manual Measuring tools
• Non-Graduated Manual Measuring Tools• Special Purpose Measuring Tools
• Non-Destructive Inspection Pressure and Vacuum Measurements Thermometry
and Pyrometry. Flow Metering Measurement of Weight The Three Common
Methods of Rotational Speed Measurements • Environmental and Pollution
Measurements
13
263
MACHINE SHOP MACHINERY AND EQUIPMENT
Purpose and Scope • Standard Machine • Special Tools and Machinery in Machine Shop
of a Manufacturing Plant • Sizes of Motors for Machine Shop Equipment and Forging
Machinery• Machine Screws Gearing Guarding of Point of Operating in Turning,
Drilling, Shaping, Milling And Grinding Operations
14
282
MANUFACTURING PROCESSES
Definitions Classification of Manufacturing Processes • Processes • Shielded Metal Arc
Welding . Safety Precautions • Pollution Control • Anti- Pollution for Manufacturing Processes
15
298
FUELS AND LUBRICANTS
Fuels . Solid Fuels • Coke • Wood and Hogged Fuel • Miscellaneous Solid Fuels
• Liquid Fuels Storage and Handling of Fuel Oil • Gasoline and Kerosene • Diesel Fuel
Oils • Gaseous Fuels • Diesel Lubricating Oils • Units of Heat Measurement
‘
16
318
MATERIALS
Tools Steels • Standards Steels • Corrosion-Resistant Steels • Heat Treatment of Steel
• Non-Ferrous Alloys. Etching
17
353
INSTRUMENTATION
Purpose • Scope. Definitions • Outline of the Identifications System
• Instrument Line Symbols
APPENDICES
CODE OF ETHICS
BOARD OF MECHANICAL ENGINEERING RESOLUTIONS
•
Drawings
377
CHAPTER 1
-
GENERAL
Chapter 1
GENERAL
Section 1.0 Scope
(a) Assembly of pipes on racks and supports,
This chapter provides the general requirements for
works involving machinery design, installations and
operations.
(b) Complete
individual
piping
system,
indicating terminal to terminal valves,
fittings, size and color code.
As used in this code, and as defined in Article I
Section 3 Paragraph (b) Republic Act No. 8495,
otherwise known as The New Mechanical Engineering
Law, mechanical equipment/machinery or process
shall include steam engines, internal combustion
engines, boilers, turbines, crushers, mills, mixers,
compressors, cranes, conveyors, hoists elevators,
pipelines, line shafting, etc.; and the term “mechanical
works, plant,” shall include steam plants, internal
combustion engine plant, hydraulic power plants,
pumping plants, refrigerating plants, air-conditioning
plants, mill shops, factories, shipyards, etc. containing
any mechanical equipment, machinery or process.
Section 2.0 Requirements for Permit
Application
All proposed installations, additions or alterations
involving machinery, mechanical equipment or
process shall be covered by the following plans and
specifications prepared by or under the supervision of
a Professional Mechanical Engineer signed and
sealed by same. Such plans in triplicate shalt
accompany applications for installation and operation
permit.
2.1
2.2
2.3
General layout plan for each floor drawn to scale
not less than 1:200, in heavy lines the
equipment with super-imposed building outline
in light or suppressed lines. All names of
machinery and brake horsepower or kilowatt
rating should be noted on plan.
2.4
Separate plan for the different store rooms, fuel
tanks, fire extinguishing equipment, fire fighting
tools, fire doors, fire escape ladders, etc., which
were not incorporated in Section 2.1.
2.5
For air conditioning and refrigeration installation
or ventilation, plans for supply and return
ductwork should indicate the location of outlet
dampers, controls, filters, fire proofing, sound
insulators.
2.6
Detailed plans of foundations and supports.
2.7
Detailed construction and working plans of
boilers and pressure vessels, if any.
2.8
Location plan preferably drawn to scale.
2.9
Complete list of machineries showing:
(a) Machinery name:.
(b) Catalogue
number
number,
model,
serial
(c) Rated capacity (Ex. Boiler Steam capacity in
Kg/Hr, kW, kJ)
(d) Drive and Revolutions per minute
(1) Direct
(2) V-belt or flat belt
Plan elevation at least one longitudinal and one
traverse to show inner floor relations indicating
how machines are supported whether through
building structure, separate staging or by
foundations from the ground.
(5) Magnetic
Piping plan in isometric drawing:
(6) Chain
I
size,
(3) Gear reducer
(4) Hydraulic
____
CHAPTER 1
-
GENERAL
(7) Line Shafting
(e) Motor or Prime Mover Showing:
Electrical windings
electro-magnets,
resistance etc.
Cast and malleable iron
(Also for general use
of all materials)
(1) kW for each machine
000
Steel
(2) speed in RPM
(3) total kW installed, or to be installed
•
/
Bronze, brass, copper,
and compositions
2.10 Flow-sheet if processing plant, manufacturing or
assembly plant with the corresponding standard
symbols.
,“<,i
?? ;:;, /
White metal, zinc,
lead, babbit, and
alloys
2.11 Other Contents of Mechanical Plans:
Magnesium, aluminum,
and aluminum alloys
The Plans shall also contain the signature and
seal of a Professional Mechanical Engineer with
the following:
Concrete
Brick and stone
Marble, slate, glass
porcelain, etc.
hEanh
Rubber, plastic
electrical insulation
Rock
(a) Registration number
(c) Professional Tax
Place of Issue
Receipt (PTR),
Date,
Sound
insulation
V
(d) Tax Identification Number
?‘?‘1
r
Section 3O Standards for Drawings
3.1
Cork, felt, fabric.
leather, fiber
— — —
(b) Validity Date
Metric Dimension on Drawings.
Length in metric units that are most generally
used in connection with any work relating to
mechanical engineering are meters and
millimeters. One meter equals 1,000 millimeters.
On mechanical drawings, all dimensions are
general, given in millimeter, no matter
how large the dimension may be. In fact,
machinery as
of such
dimensions
al apparatus
electric
locomotives and large
This
in
millimeters.
ively
exclus
are given
practice is adopted to avoid mistakes due
to misplaced decimal points, or misread
dimensions as when other units are used
as well. When dimensions are given in
millimeters, most of them can be given
without resorting to decimal points, as a
millimeter is only little more than 1/32
inch.
HH
[
—
.ZEEEtEI
Sand
Water and other
liquids
Thermal
insulation
Wood
Across grain
Firebrick and
refractory material
WoodWith grain
Fig. 1-1 Standard Symbols for Section
Only dimension or precision need be given in decimals
of millimeters; such dimensions are generally given in
hundredths of a millimeter, for example, 0.02 mm,
which is equal to .0008 in. As .01 mm is equal to .0004
in, it is seldom that dimensions would be given with
greater accuracy than hundredths of a millimeter.
2
CHAPTER 1
PENCIL LINES
THICK
VISIBLE LINE
MEDIUM
MIDDEN LINE
THIN
CENTERLINE
Leader
Extension Line
Dimension Line
ThIN
5
6
THIN
7.
4__
THICK
—
—
TI4tN
— —
THIN
4
—
,—
DIMENSION
LINE
EXTENSION
LINE
ANDREADERS
I
r161I
1714
THICK
4
T__
THIN
}
10
Fig. 1-4 Application of surface symbol to drawings
—
—
THICK
—
—
—
—
THICK
...—.—._——-—-.——.——————
.
EREAK LINES
y
PHANTOM LINE
——
THICK
—
—
v/
VI_
THIN
4__
9
12
Oimensin Line
THIN
__4i CUTTING -PLANE { 8
L
—.———-——--—-———————
Leader
Extension Line
I
LINES OR
VIEWING-PLANE
LINES
10
MEDIUM
2
SECTION LINE
THIN
4
GENERAL
INK LINES
THICK
3
-
THIN
THIN
12
— —
Fig. 1-5 Proportions for surface symbol
WIDTH AND CHARACTER OF LINES
WIDTH AND CHARACTER OF LINES
Three width of lines thick, medium, and thin are recommended
for use on drawings. Pencil lines in general should be in proportion
to the ink lines except that the ticker pencils will be necessarily
thinner than the corresponding ink lines, but as tick as practicable
for pencil work. Exact thickness may vary according to the size and
type of drawing. For example, were lines are close together, the
lines may be slightly thinner.
—
—
SECT1ONA.A
Fig. 1-2 Standard Lines for Engineering Drawings
Roughness He,ght (00)
Roughness Heriht (1D)
Roughness Width Cutoff
Waxiness Height
(00)
Waviness Height
(ID)
Lay (00)
las 11001
-
Roughness height rating Is
placed at the left of the long
leg. The specification of only one
,etlng shat indicate the mini
mum Value and any lesser value
shall be acceptable.
6,.7
The specification of maximum
value and minlmran Value rough
ness height ratings indicates
permissible range of value
rating
-
.002 -2
63
32
..L
Maximum waxiness height rating
is placed above the horizontal
extensIon. Any lesser rating shall
be acceptable.
2
Maximum waxiness width rating
is placed above the horizontal
extension and to the right of the
waviness height rating. Any len
serrating shat be acceptable.
7i5
Lay designation is indicated by
gre ta symbol plucod at the
right o the long leg.
Where required, maximum
roughness width rating shed be
.020 parted at the right of the lay
symboL Any lesser rating shall
be acceptable.
7i’
3,/’.L.
001
Fig. 1-6 Interpretation of surface symbol data
Roughness width cutoff rating
is placed below the horizontal
extension when no value is
shown. 0.030 Is assumed.
.002-2
63
030
002
Circcn,Ierestiat
Asel
Roughness Height (00)
63 Mu in.
Roughness Height (ID)
32 Mu in.
Roughness Width Cut-off
030
Waviness Height (0D)
002
Waviness Height (ID)
001
Lay (OD)
Circumferential
Lay (ID)
Axial
.002-2
002
.002
Maximum reqsirements forcestact or bearing area with a rat
ing part of reference surface
shall be indicated by a percent
gge value placed above the
extension line as shown further
requirements may be controlled
by notes.
63
32
Fig. 1-3 Application of symbols and specifications
for surface finish
3
CHAPTER 1
-
GENERAL
part under this Code provided that all
the programs to be used are
appropriate
and
documented
satisfied.
are
Code
provisions of this
entation:
Docum
2. Program
program
ter
compu
a
enting
Docum
under this Code shall consist of filing
with the Philippine Mechanical Code
Commission)
(the
Commission
reference publications accessible to
the Commission where the detailed
description of the program or a brief
theoretical
the
of
statement
including
m
progra
the
of
ound
backgr
a description of the algorithms used
are found.
3. Computer Generated Computations: A
copy of the output sheets shall be
submitted as part of the design
be
shall
which
computations,
a
by
ation
certific
a
by
accompanied
that
er
engine
nical
mecha
ional
profess
the output sheets are the results
obtained through the use of
The
programs.
documented
certification shall include the name
and document reference number(s) of
the specific program(s) used for each
portion of the computer generated
computations being submitted.
Drawings:
Generated
4. Computer
Computer generated drawings shall
conform to the provisions of Section
1.2, 1.3, and other provisions of this
Code.
SPECIFYARAEAS AFFECTED
SURFACE ROUGHNESS
.XX)(-.XXXDIA
XXX.XXX DEEP
-
X)(X- XX CBORE
XXX-XXX DEEP
XX
XXX-.XXX CBORE
,XX)I-XXX DEEP
.XXXX-XXUNF -ZB
XXX DEEP MINIMUM FULL FROM THREAD
“
WELL
GRWD
LAP
//L
f designating surface roughness on a
Fig. 1-7 Meth
process drawing tor several operations on same surface
3.2
Scales of Drawing.
Drawings made using the International System
of Units should not be made to scales of 1:2,
1:4, 1:8, etc. If the object cannot be drawn full
size, it may be drawn 1:2.5, 1:5, 1:10, 1:20,
1:30, 1:100, 1:200, 1:500, or 1:1000 size. If the
object is too small and has to be drawn larger it
is drawn 2, 5, or 10 times its actual size. The
scale therefore shall be written 2:1; 5:1; 10:1.
3.3
Standard sheet sizes:
Section 4.0 Inspection
Standard sheet sizes for mechanical plans and
drawings shall be based on a width to length
ration of 1: square root of 2. All borders shall be
at least 10 mm from the sheet edge; and all title
blocks shall be located at the lower right hand
corner inside borders for larger sheets, and
throughout the lower sheet border for smaller
sheets. Standard sheet sizes shall be as follows:
1.
2.
3.
4.
5.
6.
7.
A4:210x297mm
A3:297x420mm
A2:420x594mm
A1:594x840mm
375x530mm
530x750mm
750x1065mm
Inspection shall be done during installation to
office of respective
inspection
satisfy
ned that all materials
concer
government agency
are inspected in
n
erectio
of
s
and method
code.
this
with
mance
confor
4.2
Annual inspection shall be made to see that:
(a) Equipment as originally installed are still
safe to operate for at least another year.
(b) No change, addition or alteration deviating
from the original plan was made without
prior permit from the proper government
agency concerned.
A. Use of Computers
1.
4.1
Computers may be used for all or any
part of the design or mechanical plant,
facility, system, machine or machine
4
CHAPTER 1
-
GENERAL
150mm
drawn by
checked
Title
drwng. no.
by
scale
p. m. e.
sheet no.
owner
20
20
Fig. 1-8 Title Block
5
CHAPTER 2- COMMERCIAL AND INDUSTRIAL BUILDING
Chapter 2
COMMERCIAL AND INDUSTRIAL BUILDING
d.
Section 1.0 Scope
This chapter covers general guidelines in the choice
and design of industrial building. It includes safety
rules and requirements for the various aspects of
industrial buildings, and matters on machinery and
equipment foundation designs.
Section 3.0 General Requirements
3.1
Section 2.0 Plant Design Procedure
2.1
Space Requirements
a.
Work Rooms (referring to maintenance shop
and machine room) shall be at least 3 000
mm in height from floor to ceiling.
b.
The maximum number of persons working
or will be working shall not exceed one
person per 12 cubic meter. In calculating
the working space requirement, no
deduction shall be made for benches or
other furniture, machines or materials but
height exceeding 3 000 mm shall be
excluded.
Basis of the Structure Design.
For indust 31 works, the utilization demand of
the industry for which the building is to be used
are of utmost importance in the design of
buildings.
Aside from geographical location and economic
consideration, the mechanical and electrical
extremely
are
requirements
equipment
particularly
buildings,
all
modern
for
important
factories.
2.2
3.2
Requirements for number, size, location and
height of rise for elevators with particular
attention to penthouse dimensions and
equipment loads.
a.
b.
c.
For industrial buildings, all specific demands
of the manufacturing processes such as
special mechanical and electrical equipment
of interior clearances, should be identified.
General requirements for plumbing with
particular attention to the location of soil
stacks, standpipes, main pumps, waterstorage tanks and sprinkler systems.
If steam is to be produced within the
buildings, requirements of the boiler room
and accessories, such as fuel storage, the
probable location of steam mains and ducts
and their approximate sizes in order to avoid
interference with a structure member of
other utilities.
3.3
Typical lighting demands with particular
attention to ceiling outlets as their proper
locations may influence the framing of the
building and the necessary space required
for the electric conduits often affect the floor
design.
6
Crowding of Floor Space
a.
The floor space in a machine room shall
strictly follow safety requirements and shall
not be crowded with machineries in a
manner dangerous to employees, or be over
crowded with materials or products so as to
constitute hazards to them.
b.
Sufficient space shall be provided around
the individual machine or process units to
allow for normal operation, adjustments,
ordinary repairs, and for material supplied,
in process or completed.
Stumbling Hazard
a.
The parts of floors over which any person is
liable to work shall be sufficiently even to
afford safe walking and safe trucking of
materials.
b.
Such parts shall be free from holes and
splinters, improperly fitted covers for gutters
of conduits, protruding nails and bolts,
projecting valves or pipes, or other
CHAPTER 2- COMMERCIAL AND INDUSTRIAL BUILDING
projections and obstructions which might
create stumbling hazards.
3.4
b.
b.
Other floor openings into which persons can
accidentally fall through shall be guarded
either by permanent railings and toe boards
on all exposed sides or by hinged floor
opening covers of adequate strength.
c.
When covers for either type are not in place,
the opening shall be constantly attended to
by someone or protected by portable
enclosing railings.
d.
Floor openings into which person can
accidentally walk on account of fixed
machinery, equipment or walls shall be
guarded by covers securely held in place
and leaving no openings more than 25 mm
in width or by toe boards on all exposed
sides.
e.
All wall openings less than 1 000 mm from
the floor having a height of at least 750 mm
and width of 450 mm from which there is a
drop of more than 2 000 mm shall be solidly
enclosed or guarded by fixed or rolling
barrier rails, picket fences, half doors, or
equivalent barriers, capable of withstanding
a load of at least 100 kg applied in any
direction except vertically upward at any
point on the top or corresponding member.
f.
All other wall openings, irrespective of their
width shall, if their lower edge either 80 mm
or less above floor level on the near side or
2 000 mm or more above ground, or floor
level on the far side, be guarded by:
Floors, stair treads and landings shall not be
slippery under any condition or made of any
material which will become slippery through
wear. In the case of concrete stairs, it
should have a rough finish and for steel
stairs, checkered plate or standard metals
and non-slip strip shall be used.
Stairways, ramps, elevators, platforms and
similar places where slipping may be
especially hazardous, shall be provided with
non-slip walkway surfaces.
Floor and Wall Opening:
a.
Ladder way, floor openings shall be guarded
on all exposed sides, except at the entrance
to the opening, by permanent railings and
toe boards, the passage through the railings
shall be provided with a barrier or gate so
arranged that a person cannot walk directly
into the opening.
b.
Stairway floor openings shall be guarded on
all exposed sides, except at the entrance to
he stairway, by permanent railings and toe
boards.
c.
For seldom used stairways where traffic
across the opening prevents the use of
permanent railings, the guard shall consist
of a flush-hinged cover of adequate strength
equipped with railings attached thereto so
as to leave only one side exposed when the
cover is open.
d.
Hatchway chute, pit and trap door openings
(it cold be an elevator pit or a maintenance
pit) shall be guarded by:
1.
2.
3.6
Manhole floor openings shall be provided
with manhole covers of adequate strength
which need not be hinged.
Slipping Hazards
a.
3.5
a.
Removable railings with toe boards
on not more than two sides and
permanent railings with toe boards
on all other exposed sides, or
3.7
Flush-hinged cover as specified for
stairway floor openings.
A toe board across the bottom of
the opening or
2.
An enclosing screen, either solid or
of grilles or slat work with openings
not more than 25 mm in width.
Railings
a.
All railings shall be constructed in a
permanent and substantial manner of wood,
pipe, structure metal or other material of
sufficient strength.
b.
Standard railings shall be at least 1 000 mm
from the upper surface of the top rail to floor
level.
Manholes and Other Openings
7
1.
CHAPTER 2- COMMERCIAL AND INDUSTRIAL BUILDING
c.
Standard railings shall have posts not more
than 2 000 mm apart and an intermediate
rail halfway between top rail and the floor.
d.
The dimensions of railings and posts and
the anchoring and framing of members shall
be such that the completed structure shall
be capable of withstanding a load of at least
100 kg applied in any direction at any point
of the top rail.
e.
Railing of the following types of construction
shall be deemed satisfactory:
1.
2.
3.
f.
g.
h.
For Wood Railings: Top rails and
posts of at least 50 mm x 100 mm
stock and intermediate rails of at
least 50 mm x 50 mm x 20 mm x
100 mm stock. All such railings
shall be smooth and free from large
or loose knots, protruding nails or
bolts, splinters, fine slivers or
cracks.
For Pipe Railings: Top rails and
posts of metal pipe of at least 30
mm diameter. And intermediate rails
of metal pipe of at least 25 mm
diameter.
For Structural Metal Railings:
rails and posts of angle iron at
38 mm x 38 mm x 5 mm
intermediate rails of angle iron
least 32 mm x 32 mm x 3 mm.
Top
least
and
of at
c.
Except for service stairs, the pitch of
stairways should be between 30° and 38°
from the horizontal and the slope should not
be less than 20° or more than 45°.
d.
Where the slope would be less than 20°, a
ramp should be installed, and where the
slope is more than 45°, a fixed ladder should
be provided.
e.
No stairway shall have a height of more than
2 750 mm between landings, and
intermediate landings shall have dimensions
of not less than 1 120 mm measured in the
direction of the run.
f.
Headroom shall be provided at all points in
the stairwell. The vertical clearance shall not
be less than 2 200 mm from the top of the
tread in line with the face of the riser.
g.
Except for service stairs, the treads,
exclusive of noosing or projections, shall not
be less than 230 mm in width and the risers
shall not be more than 200 mm or less than
130 mm in height.
h.
There shall be no variation in the width of
the treads and the heights of the risers in
any flight; the top and bottom treads of any
flight should be clean’ distinguishable.
All stairways having four or more risers shall
be equipped with stair railings on any open
side.
Toe boards shall be at least 150 mm in
height.
j.
Enclosed stairways less than 1 120 mm in
width shall be equipped with the stair
railings on any open side.
k.
Enclosed stairways less than 1 120 mm in
width shall be equipped with at least one
handrail, preferably on the right side
descending.
Toe boards may be made of wood, iron,
steel or other substantial material.
Stairs
a.
Width of stairs except service stairs, i.e.
giving access to oiling platforms, shall in no
case be less than 900 mm and should be at
least 1 120 mm away from all obstruction
except handrails.
All railings shall be of sound material free
from defects and all sharp corners shall be
rounded and smoothed.
Toe boards shall be securely fastened in
place with not more than 6-mm clearance
above floor level.
3.8
b.
Stairways 1120 mm or more in width shall
be equipped with one stair railing on each
open side and one handrail on each
enclosed side.
All stairs, platforms, and landings shall be of
sufficient strength to sustain safely a live
load of not less than 500 kg with a factor of
safety of four (4)
8
CHAPTER 2- COMMERCIAL AND INDUSTRIAL BUILDING
m. In addition to the railings provided for in
Section 3.8, stairways 2 250 mm or more in
width shall be equipped with an intermediate
handrail located approximately midway of
the width.
n.
Stair railings shall be constructed in a
permanent and substantial manner of wood,
pipe, structural metal or other material of
sufficient strength.
o.
The height of stair railings, from the upper
surface of the top rail to the surface of the
tread in line with the face of the riser at the
forward edge of the tread, shall not be more
than 860 mm nor less than 760 mm.
p.
Handrails shall be continuous throughout a
flight of stairs and at landings and without
obstructions other than those intended to
prevent persons from sliding.
q.
r.
s.
t
u.
v.
slats, or grill work to prevent persons from
falling through.
3.9
If made of wood, handrails shall be at least
50 mm x 50 mm in cross section and if of
metal pipe, at least 40 mm in diameter.
x.
Ramps used by persons for ascent or
descent from one level to another shall be
limited to a slope of not more than 1 in 10
and shall conform to all relevant
requirements
for
construction
width,
enclosures and
railings applying to
stairways.
y.
Where railings for ramps may be subjected
to heavy stresses, from trucking or handling
materials, additional strength shall be
provided by use of heavier stock, close
spacing of posts, bracing, etc.
Fixed Ladders, Catwalks, Runways and
Platforms:
a.
All metal parts or fittings of ladders shall be
made of structural steel.
b.
Fixed ladders shall be so installed that:
Handrails mounted directly on walls or
partitions shall be fixed by means of
brackets attached to the lower side of the
rails, so as not to interface with the
smoothness of the top and side surfaces of
the rails.
Brackets shall be spaced not more than
2 000 mm apart and shall be of sufficient
strength to provide a clearance of at least 40
.m betweent1e rails and walls or any
.)structlon on the walls
The completed structure shall be capable of
withstanding a load of at least 100 kg
applied in any direction at any point on the
rail.
c.
The clear width of. service stairs, such as
stairs in engine and boiler rooms or stairs
leading to service platforms around
machinery, shall be at least 560 mm.
The pitch of service stairs shall not be more
than 60° and the width of the treads shall
not be less than 150 mm.
d.
w. Window openings at stair landings, where
the opening is more than 300 mm in width
and the sill is less than 900 mm above the
landing shall be guarded securely by bars,
9
1.
The distance from the front of the
rungs to the nearest fixed object on
the climbing side of the ladder is at
least 760 mm.
2.
The distance from the back of the
rungs to the nearest fixed object is
at least 160 mm.
3.
Except in the case of ladders
equipped with cages, baskets or
equivalent devices, there should be
a clearance of at least 380 mm from
the center line of the ladder on
either side across the front of the
ladder.
If fixed ladders are used to ascent height
exceeding 9 000 mm.
1.
Landing
platforms should
be
provided for each 9 000 mm or a
fraction thereof.
2.
The sections of the ladder should be
staggered.
Catwalks, working platforms or open sided
floors 2 000 mm or more above floor or
ground level, except platforms used for
loading and unloading of height, and small
platforms used for motors or similar
CHAPTER 2- COMMERCIAL AND INDUSTRIAL BUILDING
bridges or under pass should be provided,
and the track or roadway should be fenced
so as to prevent direct crossing at such
points.
equipment which cannot afford standing
space for persons, shall be guarded on all
open sides by standard railing and toe
boards.
e.
f.
Catwalks used for filling of thanks, cars or
for oiling may have the railing on one side
omitted, if necessary, subject to the hazard
of falling being reduced by the use of
runways not less than 560 mm in width.
j.
by
tracks
railway
along
Walking
prohibited.
be
should
persons
unauthorized
k.
Railings should be installed along walkways
on bridges, on steep slopes, at slippery
places and at places where pedestrians are
liable to injury by passing vehicles.
All runways or platforms constructed over
conveyors or machinery shall be guarded on
all open sides by standard railings and toe
boards.
Roadways for automobiles, tractors or other
vehicles should be soundly constructed with
surfaces made of good working materials.
3.10 Yards, Gates, Roadways, Walkway
a.
Plant yards shall be properly drained and
graded in order to facilitate safe access to
buildings and safe handling of material and
equipment.
m. Roadways should be of adequate width, and
where used by two way traffic, shall be at
least twice the width of the widest vehicle
normally used, plus 1,2500 mm. Sufficient
clearance from overhead structure should
be provided.
b.
Drain pools and catch basins shall be
provided where necessary, and be properly
covered or enclosed.
n.
c.
Ditches, pits and other hazardous openings
shall be provided with substantial covers,
enclosed, or surrounded by substantial
guards.
Where the establishment of grade or level
crossings cannot be avoided, such
crossings should be protected by watchman,
gates or automatic signals.
o.
Substantial railings or walls should be
provided along bridges, slopes and sharp
curves.
d.
Walkways, roadways and tracks for plant
railways should be carefully laid out in such
a manner as to avoid dangerous grade
crossings.
e.
Where the premises are surrounded by
fences or walls, separate entrance and exit
gates should be provided for pedestrians,
vehicular and railroad traffic.
f.
Gates for pedestrian traffic should
located at a safe distance from those
vehicular and railroad traffic and should
of sufficient width to permit passage
employees at rush hours.
Section 4.0 Machinery & Equipment
4.1
be
for
be
of
General Requirements
a.
All heavy machinery should be supported on
solid foundations of sufficient mass and
base area to prevent or minimize the
transmission of objectionable vibration to the
building and occupied space and to maintain
the supported machine at its proper
elevation and alignment.
b.
Foundation mass should be from 3 to 5
times the weight of the machinery it is
supposed to support, or may be designated
in conformance with Section 2.4. .2.
g.
Safe walkways should be constructed along
the shortest lines between important points.
h.
Walkways should not be located under the
eaves of buildings where they may become
slippery.
If the unbalanced inertial forces produced by
the machine can be calculated, a mass of
weight equal to 10 to 20 times the forces
should be used to dampen vibration.
Where it is necessary for pedestrians to
cross railroad tracks or vehicular roadways,
For stability, the total combined engine,
driven equipment, and foundation center of
10
CHAPTER 2- COMMERCIAL AND INDUSTRIAL BUILDING
gravity must be kept below the foundation’s
top.
c.
The weight of the machine plus the weight
of the foundation should be distributed over
a sufficient soil area which is large enough
to cause a bearing stress within the safe
bearing capacity of the soil with a factor
safety of five (5).
d.
Foundations should be isolated from floor
slabs or building footings at least 25 mm
around
its
perimeter
to
eliminate
transmission of vibration. Fill openings with
watertight mastic.
4.2
Specific Requirements
a.
For Stacks
Stacks and foundation
become integral structures. The maximum
pressure on the soil is equal to the pressure
due to the weight and the wind movement.
Allowable pressure may be taken as the
sum of 2,566.36 kg/m
/m deep foundation
2
plus 2,566.36 kgm
/ due to wind or a total of
2
5,132.73 kg/m
/m depth of the foundation.
2
—
1.
Guyed Steel Stacks. These are
used principally because of their
relative
cheapness.
Heavy
foundations
are
unnecessary.
Guyed stacks seldom exceed 1.83
m diameter and 30.48 meter high.
Guys are usually applied in one to
three seats. The angle between the
stack and guy wire is usually 60°,
and the angle between wires in a
set is 120° for a set of three.
2.
Reinforced Concrete Chimney.
Together with its base, this chimney
forms an integral structure. Wall
thickness decreases progressively
to the top of the stack. Less area is
required than for masonry or selfsupporting steel stack because of
the relatively thin walls compared to
masonry stacks and the elimination
of the conical flare of the self
supporting steel stack.
They can
be erected rapidly. The success
depends to a great extent upon the
care with which material is selected,
mixed and poured.
When installing machinery above grade
level of a building, additional stiffness must
be provided in the structural members of the
building to dampen machine vibration.
e.
Foundations are preferably built of concrete
in the proportion of one (1) measure of
Portland Cement to (2) measures of sand
and four (4) measures of screened crushed
stones. The machine should not be placed
on the foundation until (7) days have
elapsed or operated until another seven (7)
days have passed.
f.
Concrete foundations should have steel bar
reinforcements placed both vertically and
horizontally, to avoid thermal cracking.
Weight of reinforcing steel should be from
1/2% to 1% of the weight of foundation.
g.
Foundation bolts of specified size should be
used and surrounded by a pipe sleeve with
an inside diameter of at least three (3) times
the diameter of the anchor bolt and a length
of at least 18 ties the diameter of the bolt.
No foundation bolts shall be less than 12
mm diameter.
h.
Machine should be leveled by driving
wedges between the machine’s base and
concrete foundation and with the aid of a
spirit level. Grout all spaces under the
machine bed with a thin mixture of one part
cement and one part sand.
The level
wedges should be removed after grout has
thoroughly set and fill wedges holes with
grout.
11
CHAPTER 2- COMMERCIAL AND INDUSTRIAL BUILDING
and ramming. The top should
be level and left rough for
groutings. After pouring, the top
should be covered and wet
down twice dialing until the
forms are removed at the end of
the third or fourth day. The
engine should not be placed on
the foundation until 10 days
have elapsed, nor operated until
after another 10 days.
Table 2.1
Approximate Weight of Guyed Stacks
Per Meter of Height
Thickness of Material
Stack
Diameter
(mm)
2.75
mm
750
840
915
990
1065
1220
1370
1525
1675
1830
61.29
67.35
73.46
79.27
85.02
97.15
b.
c.
4.37
mm
3.57
mm
4.76
mm
Weight of Stacks kg/rn
75.39
82.70
111.00
90.29
119.95 136.19
97.45
144.53
104.90 127.25
119.50 144.83 165.54
135.74 165.24 185.65
150.49 182.82 208.45
200.85 229.16
218.58 249.13
-
6.35
mm
-
-
(b) Soil Bearing Pressure. The
first objective is achieved by
makings its supporting area
The safe
sufficiently large.
loads vary from about 4,890
2 for alluvial soil or wet clay
kg/rn
. (The latter is
2
to 12,225 kg/rn
assumed to be a safe load
average.) in computation 2,406
kg! m may be used as weight
of concrete.
-
-
192.66
223.50
250.62
273.86
301.43
327.35
For Steam Turbines Foundations should
have sufficient weight and mass to hold the
The
turbine rigid against vibration.
maximum unit pressure of turbine and
generator on the reinforced concrete should
. Concrete shall be
2
not exceed 17.62 kg/cm
1-2-4 mixture, well placed and seasoned. It
should be designed to support the machine
load plus 25% for impact, condenser load,
floor loads and dead loads.
—
(c) Depth. The foundation depth
may be taken as a good
practical rule, to be 3.2 to 4.2
times the engine stroke; the
lower factor for well-balanced
and
engines
multi-cylinder
with
engines
for
factor
higher
fewer cylinders, or on less firm
soil.
Manufacturers supply
Diesel Engines
foundation drawings with each engine sent
In the absence of such drawing,
out.
foundations may be designed but in no
event should absurdly shallow foundations
Foundations perform three
be allowed.
functions:
1. Support the weight of the engine.
—
2.
Maintain proper alignment with the
driven machinery, and
3.
Absorb the vibration produced by
unbalanced forces created by
reciprocating revolving masses.
(d) Weight. The minimum weight
required to absorb vibration
could be expressed as a
function of the reciprocating
masses and the speed of the
engine. However, for practical
purposes it is simpler to use the
empirical formula.
Wf=e XWeX’Ji
Where:
(a) Materials. The foundations
should be concrete, of I part
cement, 2 parts sand and 4
parts broken stone or gravel (50
entire
The
max).
mm
foundation should be poured at
one time, with no interruption
than are required for spacing
12
Wf =
we =
e =
weight of the foundation in kgs
weight of the engine in kgs
an empherical coefficient
engine speed, rpm
CHAPTER 2- COMMERCIAL AND INDUSTRIAL BUILDING
Table 2.2
Values of “e” in Foundation Formulas
Type of Engine Cylinder Arrangement
Single-acting
Single-acting
Single-acting
Single-acting
Single-acting
Single-acting
Single-acting
Double-acting
Double-acting
Vertical
Vertical
Vertical
Vertical
Horizontal
Horizontal duplex
Horizontal twin duplex
Horizontal
Horizontal with tandem
Ci/s
1
2
3
4,6,8
1
2
4
1, 2
4
(f) Anchor Bolts To prevent
pulling out of the bolts when the
nuts are tightened, the length
embedded in concrete should
be equal to at least thirty (30)
times the bolt diameter. The
upper ends are surrounded by a
50 mm or 75 mm sheet metal
pipe, 460 mm to 610 mm long to
permit them to be bent slightly
to fit the holes of the bedplate.
e
0.15
0.14
0.12
0.11
0.25
0.24
0.23
0.32
0.20
Section 5.0 Anti-Pollution for Industrial
Building
(e) Volume of Foundation. If the
weight and speed of the engine
are not known, the volume of
concrete for the foundation may
be estimated from the data in
the following table:
5.1
All machines! equipment which characteristically
generate noise shall be provided with
appropriate enclosures to control emissions so
as not to cause ambient noise level higher than
the quality standards set by the government
agency concerned. If impractical, the buildings
housing the same should be appropriately
designed or should be provided with means to
achieve compliance with the standards.
5.2
Buildings intended for noisy manufacturing
activities should be appropriately designed or
should be provided with means so as not to
cause ambient noise level higher than the
standards set by the government agency
concerned.
Table 2.3
Volume of Concrete Foundation, 3
tm
kW
No. of cylinders
1
High speed engine
0.152
Medium speed engine 0.190
Low speed engine
0.228
2
0.095
0.118
0.152
3
0.076
0.095
0.114
4
0.065
0.080
0.099
5-8
0.057
0.072
0.087
13
CHAPTER 3— POWER TRANSMISSION EQUIPT., PRIME MOVERS, MACHINES AND MACHINE PARTS
Chapter 3
POWER TRANSMiSSION EQUIPMENT,
PRIME MOVERS, MACHINES AND MACHINE PARTS
Enclosed, Enclosure a method of guarding moving
parts so that physical contact by parts of the body is
precluded. This does not prohibit the use of hinged,
sliding or otherwise removable doors or sections to
permit inspection or lubrication.
Section 1.0 Scope
—
This chapter covers provisions for safe machine
design, guarding and similar considerations for users
and designers of power transmission equipment,
prime movers, machines and machine parts. It
includes provisions for safe use, design and guarding
of danger zones except those within the points of
operation of machinery utilized in various industries.
Considerations for machine guarding and safety
provisions at the point of operation are covered under
Chapter 4. Provisions of this chapter shall not be
interpreted as alternatives to those described in other
chapters of this Code.
Flywheel a heavy wheel which by its inertia assists
in securing uniform motion of machinery by resisting
sudden changes of speed. A mechanical energy
storage device that stores momentum in a dynamically
balanced rotating mass and releases it through the
action of clutches, cams, gears or other intermittent
arrangement which engages resisting loads against
the momentum of the wheel.
—
shielded, fenced, enclosed or otherwise
Guarded
protected according to these provisions by means of
suitable enclosures, covers, casing trough, “U” guards,
shield guards, standard railings, or by means of
isolation or remoteness of location where permitted in
these provisions, to minimize or remove the possibility
of accidental contact.
Scope 2.0 Definitions
—
Accidental Contact shall mean inadvertent physical
contact between personnel or other materials with
power transmission equipment, prime movers,
machines or machine parts which could result from
slipping, falling, sliding, tripping or any other
unplanned action or movement.
—
Guarded By Location that the moving parts are so
protected by their remoteness from the floor, platform,
walkway, or other working level, or by their location
with reference of accidental contact or dangerous
approach to by persons to object.
—
Belt Shifter a device for mechanically shifting belts
from tight to loose pulleys or vice versa; or for shifting
belts on steps of step-cone pulleys.
—
an area around the points of
Danger Zone
operation, the prime mover and the transmission
system, where personnel or materials other than those
in process in the machine may come in contact, or be
caught by or between moving and/or stationary parts
of the machine. This includes areas where materials or
stock are fed into, processed and/or discharged from
the machine.
Internal Combustion Engine a type of prime mover
utilizing the energy from expanding combustion gases
to produce mechanical energy. Internal combustion
engines may be classified according the type of fuel
used (i.e. gasoline, diesel, propane, etc.); according to
the arrangement of combustion cylinders (i.e. vertical
in-line, vee, Lenoir, Brayton, Otto, jet, 2-stroke, 4stroke, etc.). Suitable guarding and protection shall be
provided against heat, vibration, noise, explosion and
fire.
—
—
normally a prime mover utilizing
Electric Motors
magnetic energy from flowing electric currents to
produce mechanical energy, usually in the form of
rotational or shaft energy. While electric motors may
also be designed for other benefits, other than
mechanical work, the provisions for guarding and
safety design for prime movers, moving parts, and
general machine design as provided by this Code shall
apply.
—
Machine the driven unit, appliance or equipment as
distinguished from the driving unit, transmission
equipment or prime mover. The machine shall consist
of fixed and movable parts characteristic to the
process or type of operation which it is intended to
perform.
—
14
CHAPTER 3- POWER TRANSMISSION EQUIPT., PRIME MOVERS, MACHINES AND MACHINE PARTS
Machine Parts as used in this code shall mean all
moving parts of the machine, except those forming
part of the point of operation.
Section 3.0 Guards
—
3.1
Nip-Point Belt and Pulley Guard a device which
encloses the pulley and is provided with rounded or
rolled edge slots through which the belt passes.
-
Pneumatic Motor
potential energy
—
Point of Operation
General Requirements
a.
Type of Guarding Required.
Where
guards are required, they shall be of proper
design, constructed of materials as listed in
Table 3.1, adequately rigid and secured in
place, and shall shield, fence, rail, enclose,
guard or otherwise protect the employee
against accidental contact with the
dangerous moving parts of prime movers,
power transmission equipment, machine
and machine parts.
b.
Guards may be provided with hinges or
removable mechanisms whenever it may be
necessary
to
change
belts,
make
adjustments or apply lubrication to the
guarded parts.
a type of prime mover utilizing the
—
the part of the machine which
performs an operation on the stock or materials and!
or that point of location where stock or material is fed
to the machine. A machine may have more than one
point of operation.
Power Transmission Equipment
all mechanical
means of transmitting power from a prime mover to a
machine.
—
Prime Mover
an engine or motor operated by
steam, gas, air, electricity, liquid or gaseous fuel,
liquids in motion or other forms of energy and whose
main function is to drive or operate, either directly or
indirectly, other mechanical equipment.
3.2
—
Specific Requirements
a.
Disk guards shall consist of a sheet metal
disk not less than 0.80 mm (Gauge #22 u.s.
Std. gauge), or other material that will give
equivalent rigidity. Such disks, where
installed, shall be securely fastened to
exposed sides of spokes or parts equivalent
to spokes in rotating power transmission
equipment and machine parts. Materials
used for disk guards shall have smooth
surface, free from burns, slivers, nails, bolt
heads, or other projection provided,
however, that round head machine screws
or bolts may be used with metal disks under
conditions that make counter-sinking
impracticable.
b.
A shield guard shall consist of:
Process Machine a machine designed and operated
for a specific purpose and includes machine tools and
processing devices subject to regular attention.
-
Tail Rod the extension of piston rod passing through
a stuffing box in the outside head of an engine
cylinder, compressor cylinder or pump cylinder.
—
Transmission Machinery
shall refer to a closed
system of machine parts through which mechanical
energy from a prime mover or energy source is
transferred, relayed, converted, regulated, controlled
and delivered to another machine system or
appliance. The system may comprise of shafting,
wheels, drums, pulleys, couplings, clutches, drive
belts, sheaves, chain and sprockets, gears, torque
connectors, speed reducers, or other power
transferring device.
—
Turbine
a prime mover consisting of fixed and
moving blades or vanes which direct and harness
energy from flowing fluids and converts it to
mechanical energy. Flow energy of working fluids or
media include but are not limited to: expanding steam
as in the case of steam turbines; expanding
combustion gases for gas turbines; and flowing water
(as it falls from a higher elevation to a lower) as for
hydraulic turbines.
1.
A suitably rigid frame filled or
sheathed
with
wire
mesh,
expanded-, perforated- or solid
sheeting material such as metal,
plywood, plastic or the similar
covering material; or
2.
Metal, plywood, plastic or its
equivalent sturdiness which will,
without frame, give the required
protection. If the area of shield
guard, wire mesh, expanded metal
in a frame exceeds 0.55 m
, it shall
2
be reinforced. The wire mesh or
expanded metal may be fastened to
a frame of 9 mm diameter round
—
15
I
CHAPTER 3— POWER TRANSMISSION EQUIPT., PRIME MOVERS, MACHINES AND MACHINE PARTS
parts are guarded and the lubricating
devices, are piped outside the guard.
rod, 20 mm x 20 mm x 3 mm angle
metal
other
some
or
iron
construction of at least equivalent
strength.
c.
3.3
Trough or “U” guards shall be
constwcted of material specified in
Table 3.1. Edges shall be smooth
and, if the size of guard so requires,
these edges shall be reinforced.
4.
An enclosure guard shall be
constructed of material specified in
Table 3.1, except for standard
railing; and shall be so installed that
it completely guards the power
transmission equipment or moving
parts so that physical contact is
prevented.
3.5
Railing guards and toeboards where
required under any item in this code shall
comply with the provisions of Section 2.3.7.
b.
c.
Where the guard or enclosure is within 100
mm from the moving parts, openings on the
guard shall be of such size as will prevent
passage of any object greater than 12 mm
in diameter.
Where guards are located more than 100
mm and less than 380 mm from moving
parts, the maximum opening shall not be
more than 50 mm and where slotted guards
are used, the width of the opening shall be
not greater than 25 mm.
Standard railing guards shall be placed no
less than 380 mm no more than 500 mm
from any moving parts, provided however
that where clearances from other moving
parts of are less than 380 mm, such parts
shall be guarded as required elsewhere in
this code.
Transmission equipment, machines and
machine parts in inaccessible locations,
which are to be lubricated while they are in
motion, shall be equipped with extension
lubricant fittings or other methods of
lubrication which can be serviced from an
accessible location.
Guarding of Flywheels
a.
Prime Mover Flywheels. Any exposed part
of a flywheel 2 100 mm or less above
working level shall be guarded.
b.
When a flywheel extends into a pit or is
within 300 mm of floor and a standard railing
guard is used, a standard toe board shall
also be provided.
c.
When it is necessary to move, swing, spin or
push flywheels for starting, guards may be
removable or provided with momentary
openings which shall immediately closed
after such starting operation is completed. A
slot opening for jackbar will be permissible,
as provided in Section 3.5 D.
d.
Every jackbar should be equipped with a
hand stop so located that it will safely clear
the flywheel guard when fully inserted but
will prevent the worker’s hand being pinched
between the slot and bar.
e.
Machine Flywheels. Machine flywheels
having spokes (or parts equivalent to
spokes), or projections, any part of which is
2 100 mm or less above floor or working
level shall be guarded.
Clearances
a.
3.4
3.
c.
3.6
Flywheel Ball Governors: Fly Ball Governors
located 2 135 mm or less above the floor,
platform or working level having rotating,
projecting or sectional parts, or hazardous
recesses shall be guarded.
3.7
Conveyors:
Opening for Lubrication
a.
b.
Where application of lubrication must be
done, openings with hinged or sliding covers
shall be provided.
a.
Where machines or machine parts must be
lubricated while in motion the lubricating
devices shall be located at least 300 mm
from dangerous moving parts unless such
16
Screw conveyors 2 100 mm or less above
floor or other working level shall be
completely covered with substantial lids
except that screw conveyors 600 mm or less
from its top to the floor or working level,
whether its axis be above or below the floor
level which may be guarded by standard
CHAPTER 3— POWER TRANSMISSION EQUIPT., PRIME MOVERS, MACHINES AND MACHINE
PARTS
b.
c.
d.
railing guards having toe boards of midrail
height or by substantial cover or gratings.
e.
All belt conveyor head pulleys, tail pulleys,
single tension pulleys and dip take-up
pulleys shall be so guarded that the entire
sides of the pulleys are covered and the
guard shall extend in the direction of the run
of the belt at such distance that a person
cannot reach behind it and be caught in the
nip point between the belt and the pulley.
Conveyors passing over areas that are
occupied or used by employees shall be so
guarded as to prevent the material handled
from falling on and causing injury to
employees.
f.
Where workmen pass under the return
strands of chain conveyors a shallow trough
or other effective means of sufficient
strength to carry the weight of the broken
chain shall be provided.
Portable inclined conveyors shall have head
and tail pulleys or sprockets and other
power transmission equipment guarded
accordingly.
3.8
Process Machine Power Control:
Where necessary to pass over exposed
chain, belt, bucket, screw, or roller
conveyors, such crossovers shall be
provided with catwalk or bridge with
standard railings and toe boards and shall
have a safe means of access either fixed
ladder, ramp, or stairway.
Table 3.1 Materials for “U” Guards
Material
13
B
Mm.
C
A
Largest
Height of
Minimum
Clearance at Mesh or
Guard
Thickness
All Points Opening
from
Gage
No.
(mm)
Allowed
Floor
(mm) Gage #
(mm)
Level
(mm)
under 100
10
1.6 mm (#16)
1,800
100— 380
50
2.8mm (#12)
1500
under ico
10
1.25mm (#18)
1,800
100—380
50
2.36mm(#13)
1,500
Under 100
10
.65 mm (#20)
1,800
100— 380
50
2.00 mm (#24)
1,500
Under 100
.80mm (#22)
1,800
100— 380
.80 mm (#22)
1500
Under 100
6mm
1,800
—
Woven Wire
Woven Wire
Expanded Metal
ExpandedMetal
Perforated Metal
Perforated Metal
Sheet Metal
Sheet Metal
Plywood or
equivalent
Plywood or
equivalent
Solid wood
Solidwood
Wood or metal strip
crossed
-
-
Under 100
100—380
Under 100
-
Wood ormetalstrip
crossed
100—380
Wood or metal strip
not crossed
Under 100
Wood or metal strip
not crossed
100— 380
Standard Rail
Mm. 380
Standard Rail
Max. 500
—
—
—
-
6mm
25mm
25mm
10
Wood 19 mm,
Metal 1.60mm
(#16)
50
Wood 19 mm,
Metal 1.60 mm
(#16)
100 width Wood 19 mm,
Metal 1.60 mm
(#16)
25 width Wood 19 mm,
Metal 1.60 mm
(#16)
See standard for railings
(2.3.7)
See standard for railings
(2.3.7)
-
-
1,500
1,800
1,500
1,800
b.
Where an operator attends one or more
process machines not equipped with
individual drives, each machine shall be
equipped with stopping device which can be
safely actuated from the operator’s working
position at the machine, such a stopping
device may stop an entire group of
machines by stopping the prime mover,
power transmission or it may be a machine
clutch, cut-off coupling, or tight and loose
pulley with belt shifter which can stop all the
machine. Pole or hand shifting of belt is not
considered
adequate
means
for
disconnecting the power.
c.
Where practicable, each process machine
simultaneously attended or operated by
more than one employee shall be equipped
with a machine power control for each
employee exposed to or within the vicinity of
points of operation. Said controls shall be
interlocked in such a manner to prevent
operation of machine unless all controls are
operated simultaneously.
d.
Machine power controls shall be maintained
in safe operating condition, and shall be so
1,500
17
Each process machine driven by an
individual prime mover shall be equipped
with emergency stopping device which can
be safely actuated from the operator’s
working position unless the machine is
equipped with automatic clutch which will
stop or disengage all machine operation.
Exception: Where due to the process,
machines must be operated in groups, the
machine power control may stop the entire
group of machines, such group drives shall
be provided with conveniently located,
readily accessible, and properly marked or
identified emergency stop devices.
-
100—380
a.
PARTS
CHAPTER 3— POWER TRANSMISSION EQUIPT., PRIME MOVERS, MACHINES AND MACHINE
and where the distance between any two
adjacent belts or pulleys does not exceed
900 mm.
designed, installed, and/or located that they
are not likely to operate from accidental
contact with objects or parts of the body.
3.9
Machine Power Control. All machines shall be
equipped with adequate means whereby the
operator of the machine or some other person
may disconnect the power promptly in case of
emergency.
3.10 Revolving and Reciprocating Parts
a.
Hazardous revolving or reciprocating parts
in any machine not guarded by the frame or
the machine or by location shall be guarded.
b.
Keys, set screws, projections or recess in
revolving parts not guarded by the frame of
the machine or by location shall be
removed, made flush or guarded.
f.
Horizontal overhead belts more than 2 100
mm above a floor, platform or other working
level shall be guarded for their entire length
if located over passageways or working
places.
g.
Wherever there pulleys of such dimensions
and so located as to permit passage
between upper and lower runs of belt,
standard railing guard shall be constructed;
or all space traversed by belt shall be
completely barred against passage.
h.
Continuous system rope drives so located
that the condition of the rope (particularly
the splice) cannot be constantly and
conveniently observed shall be equipped
with a “telltale” device (preferably electric
bell type) that will give warning when rope
begins to fray.
i.
All rope drives shall be guarded as required
for belt drives.
3.11 Collars and couplings shall be cylindrical and no
screws or bolts project beyond largest periphery.
3.12 Clutches, cut-off couplings or clutch pulleys,
having projecting parts where any parts of such
devices is located or 2 100 mm or less above
the floor or working level shall be guarded.
3.14 Counter-balanced belt tensioner and all parts
thereof shall be of substantial construction.
Means shall be provided to prevent the
tensioner from falling in case the belt breaks; or
the area directly beneath the tensioner shall be
guarded by standard railing guards.
3.13 Guarding of Belt and Pulley Drives:
a.
Any part of a belt and pulley drive involving
the use of flat crowned or flanged pulleys,
which is 2 100 mm or less above the floor or
working level shall be guarded.
b.
Flat step-cone pulleys drives upon which the
belt operates on one step only, or step cone
pulleys drives where multi-step operation is
obtained by changing the length of the belt
shall be guarded.
c.
d.
e.
3.15 Belt-type variable speed drives located 2 100
mm or less from the floor or working level shall
have all moving parts guarded.
3.16 All gears and sprockets wherever located shall
be guarded adequately.
3.17 Friction drives located 2 100 mm or less above
floor or other working level shall be guarded.
Every V-belt and pulley drive including V
belt and step-cone pulley drives, any part of
which is 2 100 mm or less above the floor or
working level shall be enclosed.
3.18 The chains, sprocket and chain drives, located
with 2 100 mm of the floor or other working
level, shall be guarded.
If the bottom of the guard is within 100 mm
of the floor or supporting structure, the
bottom of the guard need not be enclosed.
3.19 Where workmen pass under the chain drives, a
shallow trough or other effective means of
sufficient strength to carry the weight of a
broken chain shall be provided.
Where a group of flat belt drives is guarded
by a standard railing guard, such drives
shall be considered guarded where the
distance from the vertical plane of the rail to
the nearest point of any belt or pulley is not
less than 380 mm nor more than 500 mm
3.20 Manually operated power disconnecting devices
shall be designed, constructed and installed that
18
CHAPTER 3- POWER TRANSMISSION EQUIPT., PRIME MOVERS,
MACHINES AND MACHINE PARTS
they will remain in the neutral position until
4.11
intentionally actuated.
3.21
Machine
Guarding
Other
Than
Point-of-
Operation:
Relates to the belts, pulleys, gears, shafts and
shafts ends, screws, projections, and all other
moving machine parts, other than at the pointof-operation, that constitute potential injury
producing conditions.
Table 3.4
Threshold Limit Values for Noise Exposure
Max. Sound Levels (Slow
Response), dB
8
90
6
92
4
95
3
97
2
100
1%
102
I
105
%
110
1/4
115*
*ceiling Value. No exposure in excess of 115 dB is allowed.
Hours of exposure per day, Hrs.
Section 4.0 Principle of Safe Machine
Design:
4.1
Dangerous moving parts should be enclosed.
4.2
Parts subject to wear, adjustment, and hand
lubrication should be conveniently accessible.
4.3
Lubrication
should
wherever
possible
be
automatic and continuous when the machine is
in operation.
4.4
4.12 Weight
of parts to be handled should be kept
within the limits at convenience and safety, or
these parts should be so designed that they may
be conveniently handled by mechanical means.
Consideration should be given to individual drive
so that hazards due to driving mechanism may
be minimized.
4.5
Sharp lighting, contrasts between light and
shadow and glare in the vicinity of the point of
operation should be avoided.
Color contrast
should be considered, as well as the provision of
integrally mounted lights, and the most effective
probable position of independent lighting units.
4.6
Materials should be mechanically conveyed to,
and products from machines wherever possible.
4.7
Provision should
conveying dusts
machine.
4.8
Noise should be eliminated or reduced to no
more than the maximum allowable according to
the table of threshold limit values for noise
exposure. Similarly, employee exposure to such
noise shall be limited according to Table 3.4.
4.13
Throughout the design of the machine and its
parts,
consideration
should
be
given
to
convenience
in
attaching
accessories,
particularly point-of-operation guards for moving
parts. In essence, bosses for accessories may
be cast on the framework of machines in such a
way as to permit drilling, tapping, and the bolting
on of accessories without weakening the
structure of the machine itself.
4.14
Consideration in design should be given to the
external shape of the machine so that danger of
accident from tripping, falling and collision will
be
minimized.
Splay-footed
supports,
for
example, that stand out from the body of the
machine sometimes cause a tripping hazard.
Corners may often be rounded to lessen the
danger from accidental contact.
4.15
Liberal factors of safety should
determining the strength of parts.
4.16
Wherever manufacturing circumstances permit,
point-of-operation guards should be installed by
the builder of the machines so that it may be
delivered to the purchases in a fully guarded
condition.
4.17
Consideration should be given to the safe
location or isolation of machines that cannot be
made safe otherwise.
be made for automatically
and gases away from a
4.9
Vibration should be eliminated or reduced to the
maximum permissible extent.
4.10
Machine motions tiring to the eyes should be
avoided, as when reciprocating or revolving
parts must be viewed through cross screens or
lattice-work.
Exterior shapes or any part of the machines that
require frequent contacting or handling should
be so designed as to facilitate convenience in
handling, while moving parts that cannot be
enclosed should, as far as possible, be smooth
in contour.
19
be used
in
AND MACHINE PARTS
CHAPTER 3- POWER TRANSMISSION EQUIPT., PRIME MOVERS, MACHINES
Section 5.0 Power Transmission Systems
5.1
or
(3b)
Shafting
a.
Torsional Strength of Shafting. In the
The allowable stresses that are generally used in
) for main
2
practice are: 27.6 MPa (282 kg/cm
)
2
power-transmitting shafts; 41.5 MPa (423 kg/cm
(599
MPa
58.7
and
for lineshafts carrying pulleys;
etc.
r
shafts,
counte
shafts,
short
) for small,
2
kg/cm
P
power
the
s,
stresse
allowable
Using these
transmitted by a shaft of diameter D, or the
minimum diameter of a shaft to transmit a given
power P may be determined from the following
formulas:
formulas that follow, the SI system of units
as discussed in Section 12.2.3 is adopted:
= angular velocity in radians per second;
c = distance from center of gravity to
extreme fiber;
D
=
diameter of shaft in mm;
J = polar moment of inertia of shaft cross
For main power-transmitting shafts:
4 (see Table 3.5.1);
section, m
N
=
P
(4a)
angular velocity of shaft in revolutions
r minute (RPM);
(4b)
S = allowable torsional shearing stress in
kPa
(5a)
Table 3.5.1)
N
3
D
1.738x 106
or
(5b)
(1)
3
6P
l.
8x1O
\J
D= 17
For small, short shafts:
For a shaft delivering P kilowatts at N revolutions
per minute the twisting moment I Newton-meters,
Tbeing transmitted is:
(6a)
;
x10
3
T=9,55
P
N
(2a)
(6b)
T=P
(2b)
P=
N
3
D
0.837x 106
or
D= \.JO.837xlO6P
N
Shafts which are subjected to shocks, sudden
starting and stopping, etc., should be given a
greater factor of safety resulting in the used of
lower allowable stresses than those just
mentioned.
The torque or twisting moment Tas determined by
this formula should be less than the value
determined by using formula (1) if the maximum
allowable stress S is not to be exceeded.
Illustrative Example: What would be the diameter
of a lineshaft to transmit 7.5 kW if the shaft makes
150 revolutions per minute? Using Formula (5b)
The minimum diameter of a solid circular shaft
required to transmit a given torque Tis:
(3a)
P
3 (see
= polar section modulus in m
The maximum allowable torque or twisting
moment, Tmax for shaft of any cross-section is:
or
D =‘s/1.755x 106 P
For lineshafts carrying pulleys:
T = torsional or twisting moment in N-m;
TmaxSsXZp
N
3
D
1.755x 106
or
P = power transmitted in kW;
4,
D = 1321,000 P
NS
.86mm
x7.5380
6
1
D= (1.1738x )
D=5.1T
ss
150
20
CHAPTER 3- POWER TRANSMISSION EQUIPT., PRIME MOVERS, MACHINES AND MACHINE PARTS
Illustrative Example: What horsepower would a
short shaft, 50.8 mm in diameter, carrying but two
pulleys close to the bearings transmit if the shaft
makes 300 revolutions per minute?
Using
Formula (6a)
P
=
(50.8) x 300
0.837x 106
=
fiber. This method may be used to find the
approximate value of the polar section that
are nearly round. For other than circular
cross—sections, however, the polar section
modulus does not equal the polar moment
of inertia divided by the distance c.
46.99 kW
5.2
V-Belts and Sheaves. The tapered crosssectional shape of a V-belt causes it to wedge
firmly into the sheave groove during operation
so that the driving action takes place through the
sides of the belt rather than the bottom, which
normally is not in contact with the sheave at all.
Table 3.5.1.
Polar Moments of Inertia and Polar Section Module
rMoment cThert%
Sectbn
4 or 0.1667e
a
4
Po%erSenMoths
0.20w
a.
V-Belt Drives. Belts of the V type,
commonly manufactured of fabric, cord, or
combination of these, treated with natural or
synthetic rubber compound and vulcanized
together, provide a quiet, compact, and
resilient form of power transmission. They
are used extensively in single and multiple
forms for automotive, home and commercial
equipment and in industrial drives for a wide
range of horsepower extending upwards
from fractional values.
b.
Standard Multiple V-Belt. Five sizes V
belts are designated in the Engineering
Standards for Multiple V-Belt Drives.
Nominal width and thickness dimensions are
as shown in Table 3.5.2. However, actual
dimensions
of
V-belts
of
various
manufacturers may vary somewhat from
these nominal dimensions. Because of this
fact, it is recommended that belts of different
makes should never be mixed on the same
drive. Standard V-belt pitch lengths and
permissible pitch-length tolerances are
given in Table 3.5.3.
::
:]d
[
12
r
ivhe,e d is he o,te side
b
(
or 0. 08D
0
rr1D
4
d
•
32
D
or 0.098(0’—d5
or 0. 18C
104
0.96(D-d
)
or 4
4
? 1.082s
¶)J
3
0.20F
r
4
or 0.12 F
I(
I) I
‘/\
A.
or 0 098
6
— O.167s
a
or 0
30
—
333s
0
4f4
D
J/c
/.\..
b.
328
or
— 1.oa2i
48
or 0.636s
16
or 0.
40
—2.
U
20
or 0OSs’
Table 3.5.2
Standard Multiple V-Belt Dimensions and
Recommended Test Load
Polar Moments of Inertia and Section
Moduli. The polar moment of inertia with
respect to a polar axis through the center of
gravity shall be used for problems involving
the torsional strength of shafts since this is
usually the axis about which twisting of the
shafts takes place.
Belt Section
w
The polar section modulus (also called
section modulus of torsion), Zp for circular
,-
section may be found by dividing the polar
moment of inertia, J, by the distance c from
the center of gravity to the most remote
Std Test Load
21
Type A
Type B
12.7mm
16.67mm
(21/32’)
0.32mm
(13)32”)
29.5 kg
(‘/2”)
7.94mm
(5/16)
22.73 kg
Type C
Type D
Type E
22.22mm 31.75mm
(7/8’)
(1-1/4’)
13.49mm 19.05mm
(17/32’)
(34)
38.7 kg
53.77 kg
3810mm
(1-1/2’)
23.02mm
(29/32’)
63.32 kg
CHAPTER 3— POWER TRANSMISSION EQUIPT., PRIME MOVERS, MACHINES AND MACHINE PARTS
c.
the sheaves without injury. Also shown in
Table 3.5.4 is the minimum allowance above
the standard center distance (plus values)
for which the centers should be adjustable
to take up any slack in the belts due to
stretch and wear.
Measuring a Multiple V-Belt. The pitch of
multiple V-belts is determined by measuring
fixture consisting of two equal diameter
sheaves having standard grooves and
pulled with a standard test load indicated in
Table 3.5.2. One of the sheaves is fixed in
position, while the other is movable along a
graduated scale with the specified tension
applied to it.
Table 3.5.4 Minimum Center Distance Allowances
for Installation and Take-up of Multiple V-Belts
Minimum Allowance Below (-) and
Range of
Above
(+) Standard Center_Distance
Standard
E
D
C
B
A
Lengths
-19+25 -25+25
26to38
-19, +38 -25, +38 -38, +38
38 to 60
-32, +51 -38, +51
-19, +51
60 to 90
9Oto 120 -25, +64 -32, +64 -38, +64
120 to 158 -25, +76 -32, +76 -38, +76 -51, +76
-32, +89 -51, +102-51, +102-64, +102
158to 195
-38, +102 -51, +102 -51, +102 -64, +102
195 to 240
-51,+114-64,+114-64,+114
240to270
-51+127-64+127-76+127
270to330
-51,+152-64,+152-76,+152
330to420
420 and
-89, *
-76, *
over
All dimensions in mm.
*AlIow + values to be 1.5 per cent of belt length above
standard center distance for stretch and wear.
The sheaves should be rotated at least two
revolutions to seat the belt properly in the
sheaves grooves and to equally divide the
total tension between the two strands of the
belt. The pitch length is the length obtained
by adding the pitch circumference of one of
the measuring sheaves to twice the
measured center distance between them.
Deviation of the measured pitch length from
the standard pitch length shown in Table
ould be within the tolerance limits
3.5.3
also given in this table.
-
forD =
d =
L =
C =
-
d.
4L
—
6.28 (D
-
-
-
-
-
e.
(2)
+
-
-
Selection of Multiple V-Belts. The charts
on Figure 3.5.1 appears in Engineering
Standards for Multiple V-Belt Drives enables
a V-belt of appropriate type to be selected
for a given RPM of the small sheave, the
transmitted power of the driving unit, and the
service factors are known. The selection
procedure follows:
1.
Obtain the equivalent design
horsepower (convert kW to HP) by
multiplying the transmitted HP by
the appropriate service factor from
Table 3.5.5.
2.
Enter the chart at the RPM of the
proceed
and
sheave
small
line
vertical
in
point
a
to
horizontally
with the design horsepower.
3.
If this point falls in the area marked
A, then an A size belt is required or,
This formula can be rearranged to solve for
center distance, as follows:
b
-
-
-
pitch diameter of large sheave, in mm
pitch diameter of small sheave, in mm
pitch length of belt in mm
centerdistance in mm.
where:
-
-
(1)
d)
b
32(D..
C=b 2
+q
—
16
-
-
-
Belt Length and Center Distance. The
relation between center distance and belt
pitch length is given by the following
formula:
d)
2
L2C+ 1.57 (D÷d)+(D—
4C
-
-
-
The grooves of the measuring sheaves
should be machined and maintained to the
following tolerances: pitch diameter, ±0.002
inch; groove angle, +0 degrees, 2ominutes;
and groove top width, ±0.002 inch.
c.
-
If this point falls near the line of
separation between two belt size
areas, then both sizes may be
considered as suitable for use. For
example, a design horsepower of 40
to be transmitted at a small sheave
speed of 800 RPM would call for a
multiple drive of either C or D size
V-belts.
d)
Installations and Take-up Allowance.
After calculating a center distance from a
standard pitch length, provision should be
made for moving the centers together by an
amount, as shown by the minus values in
Table 3.5.4 to permit installing the belts over
22
CHAPTER 3- POWER TRANSMISSION EQUIPT., PRIME MOVERS, MACHINES AND MACHINE PARTS
f.
Power Rating for Multiple V-Belts. The
following formulas and accompanying table
of constants (Table 3.5.6 to 3.5.9) may be
used to determine the general horsepower
rating of a single V-belt. The total
transmitted power through multiple V-belts
thus, shall not exceed the sum of individual
rated capacities of all connected V-belts.
g.
Arc of Contact. The arc of contact made by
the V-belt on the small sheave is of
importance when computing the power
rating of a V-belt for a give drive. This may
be found by the formula:
Arc of Contract = 180° (D
-
—
(5)
where D, d and C are as noted above.
Correction factors for various arcs of
contact, used in finding power capacities of
multiple V-belts drives (see example) are
given in Table 3.5.8.
(3.731)YS— 0.0057Z S
3
d
h.
where X, V and Z are factors based on the
quality of the belt used (Table 3.5.6); d
9 =
equivalent diameter of small sheave which
is equal to pitch diameter multiplied by small
diameter factor (Table 3.5.7); P = the
recommended power in kW; and S linear
belt speed in meters per second (mps), or
S=
d) 60°
C
The recommended power, P which may be
transmitted through a single V-belt for a
specified belt speed, S is given by:
P = (0.17) x S°
’
9
(3)
—
5.3
(4)
Speed of Operation. V-belts operate most
efficiently at speeds of about 23 meters per
second. For belt speeds of 25 meters per
second and more the sheave should be both
statistically and dynamically balanced.
Speed design and materials may also be
called for and the belt manufacturer should
be consulted.
Transmission Roller Chain.
60 000
a.
°uvu
3500
301K
IU
I-
—--
251K
—
—
2ftflt
—
—
—
--
II
II
B
LU
/
BEYOND H.P. B. R. P. M
RANGES SWOWN.
REFER TO
MANUFACTURER
Standard Roller Chain
Dimensions and Loads.
Table 3.5 Service Factors for Multiple V-belts Applications
II
Electric Motors
A.C.
SynSingle
Squirrel Cage
chronou
Phase
0
-J
-J
0
U.
0
800
700
600
/
300 7-200
/
100
—
D.C.
.
500
400
Nomenclature,
-
-
2
3
Z7
-z
5 67191
20 30 40 160 ‘80 100
810
507090
HORSEPOWER X SERVICE FACTOR
S
2
Applications
I—---
ew
.E
100
300
_j
500
400
Chart for Selection of V-Belt for Given Drive
o.
1()
&
‘
‘
.
0(I)
X
E
.
Z
0
Service Factors
Agitators
Paddle10
Propeller
Liquid
Semi-Liquid
1.2
Brick and clay
Machinery
Auger Machine
Do-Airing
Machines
CuttingTable
Plug Mill
1.5
Mixer
Granulator
Dry Press
Rolls
Bakery
Machinery
1.2
Dough Mixer
--
Table 3.5.7 Small Diameter Factors
Range of Speed Ratio
1.000— 1.019
1.020—1.032
1.033—1.055
1.056—1.081
1.082—1.109
1.110—1.142
1.143—1.178
1.179—1.222
1.223 1.274
1.275—1.340
1.341—1.429
1.430—1.562
1.563—1.814
1.815—2.948
2.949 and over
—
Small Diameter Factor
1.00
1.01
1.02
1.03
1.04
1.05
1.06
1.07
1.08
1.09
1.10
1.11
1.12
1.13
1.14
-
-
-
-
-
-
-
¡%
23
10 12
tO
14 12
1.2
1.4 1.4
1.4
1.2
1.4 1.4
1.4
1.2
1.3
1,2
1.2
1.2
1.2
1.4
t8
1.6
1.6
1.6
1,6
-
-
-
-
-
-
-
2.0
—
-
-
1.4
1.5
1.4
1.4
1.4
1.4
-
2.0
2.0
-
-
-
-
-
-
-
1.2 1.0
-
-
-
-
-
-
CHAPTER 3- POWER TRANSMISSION EQUIPT., PRIME MOVERS, MACHINES AND MACHINE PARTS
Compressors
Centrifugal
Rotary
1 2
—
1.2
1.2
Reciprocating-- 1.2
1.2
1.4
1.4
lor2Cyl.
Conveyors
Apron
Belt (Ore, Coal,
Sand)
Belt (Light
Package)
1 2
1 4 1 4
1 2
-
1.4 1.4
-
1.4
-
-
-
1.5 1.5
1.2 1.2 1.2
-
-
—
1.4
Table 3.5.7 Length of Correction Factors
—
-
-
-
-
-
-
1.6
-
—
1 4
1 2
1 4
1 2
1.2
1.2
-
1.6
1.4
—
—
—
..
-
2.
1 2
-
Chain Pitch: Distance in mm
between centers of adjacent joint
members. Other dimensions are
proportional to the pitch.
Tolerance for Chain Length: New
chains subjected to the standard
measuring load are allowed an
over-length of 0.99 per meter (1/84
inch per foot), but must not be
under-length.
The Measuring Load is the load in
kilograms (pounds) under which a
chain should be measured for
,
2
length. It is equal to 125 x (Pitch)
with a minimum of 8.2 kg (18 Ibs).
3.
0.81
0.84
0.86
0.87
0.88
0.81
0.83
42
46
48
51
53
0.90
0.92
0.93
0.94
0.95
0.85
0.87
0.88
0.89
0,90
55
60
62
64
66
0.96
0.98
0.99
0.99
1.00
0.90
0.92
0.93
0.93
0.94
68
71
75
78
80
1.00
1.01
1.02
1.03
1.04
0.95
0.95
0.97
0.98
0.85
0.98
0.99
0.99
1.00
0.89
A
81
83
85
90
96
97
105
112
120
128
Tensile
Ultimate
Minimum
Standard
of
pounds
in
Strength
Series single-strand chain is equal
, for multiple2
to 12,500 X (Pitch)
strand chain, multiply by number of
strands.
Table 3.6 Factors X, V. and Z for Use in Formula 3
Values of X, Y, Z factors
-
-
-
-
-
1.05
1,06
1.08
1.10
1.11
1.13
1.14
1.02
1.04
1.05
1.07
1.08
-
-
-
Belt Section
D
C
E
A
B
X
1.945
3.434
6.372
13.616
19.914
Y
3.801
9.830
26.948
93.899
177.74
Z
0.0136
0.0234
0.0416
0.0848
0.1222
Premium Quality Belts
Belt Section
A
B
C
2.684
4.737
8.792
E
f_D
18.788
24.478
263.04
0.1222
Y
5.826
13.962
38.819
137.70
Z
0.0136
0.0234
0.0416
0.0848
-
0.80
-
0.82
0.87
0.90
0.91.
0.92
0.94
0.95
0.97
0.98
1.09
1.11
1.13
1.15
0.99
1.00
1.02
1.03
1.04
180
195
210
240
270
1.16
1.18
1.19
1.22
1.25
1.05
1.07
1.08
1.11
1.14
300
330
390
420
1.27
1.16
1.19
1.23
1.24
480
540
600
660
24
-
136
144
158
162
173
Regular Quality Belts
X
C
—
—
1.
1 0
1 1
1 0
Belt Cross Section
B
I
I
Correction Factor
Standard
Length
Designation
26
31
33
35
36
_
CHAPTER 3- POWER TRANSMISSION EQUIPT., PRIME MOVERS, MACHINES AND MACHINE PARTS
Table 3.8 Arc of Contact Correction Factors
A
f
Contact
Type of Drive
Arc of
VtoV VtoFlatO Contact
Small
Sheave
Correction Factor
.
1800
1.00
.75
170°
.98
.77
160°
.95
.80
150°
.92
.82
140°
.89
.84
A V-Flat drive is one using
diameter flat pulley.
b.
Small
Sheave
Type of Drive
VtoV VtoFlato
c.
Types of Sprockets. Four different designs
or types of roller chains are shown in
sectional views in Fig. 3.5.2. Type A is a
plain plate sprocket; type B is a single
hubbed sprocket; type C is double-hubbed;
and type D, shows detachable hub
arrangement. Also used are shear pin and
slip clutch-type sprockets designed to
prevent damage to the drive or to other
equipment caused by overloads or stalling.
d.
Selection of Chain and Sprockets. The
smallest applicable pitch of roller chain is
desirable for quiet operation and high
speed. The horsepower capacity varies with
the chain pitch. However, short pitch with
high working load can often be obtained by
the use of multiple-strand chain.
Correction Factor
130°
120°
110°
.86
.82
.78
.86
.82
.78
100°
.74
.74
90°
.69
.69
a small sheave and a large
Standard Roller Chain Numbers.
The
right-hand figure in the chain number is zero
for roller chains of the usual proportions, 1
for a lightweight chain and 5 for a rollerless
bushing chain. The numbers to the left of
the right-hand figure denote the number of
1/8 inch in the pitch. The letter H following
the chain number denotes the heavy series;
thus the number 80 H denotes a 1-inch pitch
heavy chain. The hypernated number 2
suffixed to the chain number denotes a
double strand, a 3 triple strand, 4 a
quadruple strand chain and so on.
1.
2.
3.
The small sprocket selected must be large
enough to accommodate the shaft. Table
3.5.10 gives maximum bore and hub
diameters consistent with commercial
practice for sprockets with up to 25 teeth.
After selecting the small sprocket, the
number of teeth in the largest sprocket is
determined by the desired ratio of the shaft
speed. Over emphasis on the exactness in
the speed ratio may result in a cumbersome
and expensive installation. In most cases,
satisfactory operation can be obtained with
a minor change in speed of one or both
shafts.
Heavy Series: These chains, made
in %-inch and larger pitches, have
thicker link plates than those of the
regular standard.
Their value is
only in the acceptance of higher
tensile or jerk loads at low speeds.
The rollers, bushing diameters, pin
diameters, and widths are the same
as in the standard series.
—
B
Light-Weight Machinery Chain:
This chain is designated as No. 41.
It is 1/2 inch pitch; 1/4 inch wide; has
0.306-inch diameter rollers and a
0.141-inch
pin
diameter.
The
minimum ultimate tensile strength is
1,500 pounds.
c4
Figure 3.5.2 Simple Types of Sprockets
Multiple-Strand Chain:
This is
essentially an assembly of two or
more single-strand chains placed
side by side with pins that extend
through the entire width to maintain
alignment of the different strands.
For a given power load, a multiplestrand chain can be run at a higher
speed than the required singlestrand chain of a higher pitch.
e.
25
Center Distance Between Sprockets. The
center-to-center
distance
between
sprockets, as a general rule, should not be
less than 1 1/2 times the diameter of the
larger sprocket and not less than thirty times
the pitch nor more than about 50 times the
pitch, although much depends upon the
speed and other conditions.
A center
distance equivalent to 80 pitches may be
CHAPTER 3— POWER TRANSMISSION EQUIPT., PRIME MOVERS, MACHINES AND MACHINE PARTS
where C = center-to-center distance in mm;
L = chain length in pitches;
P = pitch of chain;
N = number of teeth in large sprocket,
n = number of teeth in small sprockets.
considered an approved maximum. Very
long center distances result in catenary
tension in the chain. If roller-chain drives
are designed correctly, the center-to-center
distance for some transmissions may be so
short that the sprocket teeth nearly touch
each other, assuming that the load is not too
great and the number of teeth is not too
small. To avoid interference of the sprocket
teeth, the center distance must, of course,
be somewhat greater than one-half the sum
of the outside diameters of the sprockets.
The chain should extend around at least 120
degrees of the pinion circumference, and
this minimum amount of contact is obtained
for all center distances provided the ratio is
less than 3 1/2 to 1. Other things being
equal, a fairly long chain is recommended in
preference to the shortest one allowed by
the sprocket diameters, because the rate of
chain elongation due to natural wear is
inversely proportional to the length, and also
because the greater elasticity of the longer
strand tends to absorb irregularities of
motion and to decrease the effects of
shocks.
This formula is approximate, but the error is
less than the variation in the length of the
best chains. The length, L in pitches should
be an even number for a roller chain, so that
the use of an offset connecting link will not
be necessary.
1. Idler Sprockets. When sprockets
have a fixed center distance or are
non-adjustable, it may be advisable
to use an idler sprocket for taking up
the slack. The idler should
preferably be placed against the
slack side between the two strands
of the chain. When a sprocket is
applied to the tight side of the chain
to reduce vibration, it should be on
the lower side and so located that
the chain will run in a straight line
between the two main sprockets. A
sprocket will wear excessively if the
number of teeth is too small and the
speed too high, because there is
impact between the teeth and rollers
even though the idler carries
practically no load.
If possible, the center distance should be
adjustable in order to take care of slack due
to elongation from wear and this range of
adjustments should be at least one and onehalf pitches. A little slack is desirable as it
allows the chain links to take the best
position on the sprocket teeth and reduces
the wear on the bearings. Too much sag or
an excessive distance between the
sprockets may cause the chain to whip up
a condition detrimental to
and down
smooth running and very destructive to the
chain. The sprockets should run in a vertical
being
axes
sprocket
the
plane,
approximately horizontal, unless an idler is
used on the slack side to keep the chain in
position. The most satisfactory results are
obtained when the slack of the chain is on
the bottom.
2. Length of Driving Chain. The total
length of a block chain may be
expressed in multiples of the pitch,
whereas for roller chains, the length
should be in multiples of twice the
pitch, because the ends must be
connected with an outside and
inside link.
—
f.
g.
Center Distance for a Given Length.
When the distance between the driving and
driven sprockets can be varied to suit the
length of the chain, this center distance for a
tight chain may be determined by the
following formula:
C =P[2L—N—n
8
(6)
26
Horsepower Ratings for Roller Chain
Drives. Chain drives should be protected
against dirt and moisture and the oil supply
kept free from contamination. Periodic oil
change is desirable. A good grade of nonis
oil
petroleum-base
detergent
recommended. Heavy oils and greases are
generally to stiff to enter and fill the chain
joints. The following lubricant viscosities are
recommended: For temperature of 20 to 40
degrees F., use SAE 20 lubricant; for 40 to
100 degrees F., use SAE 30; for 100 to 120
degrees F., use SAE 40; and for 120 o 140
degrees F., use SAE 50.
CHAPTER 3- POWER TRANSMISSION EQUIPT., PRIME MOVERS, MACHINES AND MACHINE PARTS
The data for each size of chain are divided
into four zones. The first is for Type I
lubrication; the second, Type II lubrication;
and the fourth; for Type IV lubrication, as
explained below. The limiting RPM for each
lubrication type is read from the column to
the right of the boundary line shown.
Table 3.11
Horsepower Ratings for Roller Chains Drive
1/2 Inch Pitch Standard Single-Strand Roller Chain No. 40
Revolutions per Minute Small Sprocket
I 50 I200I400I600900I1200I1800I2400I3000I3500I
—
No.of
Teeth
Smali
—
—
11
13
15
17
19
21
23
25
Type I. Manual Lubrication: Oil is
applied periodically with a brush or spout
can, preferably at least once every 8
hours of operation. Volume and frequency
should
be
sufficient
to
prevent
discoloration of lubricant in the chain
joints.
33
40
45
50
55
60
Type II. Drip Lubrication: Oil drops are
directed between the link plate edges from
a drip lubricator. Volume and frequency
should
be
sufficient
to
prevent
discoloration of lubricant in the chain
joints. Precaution must be taken against
misdirection of the drops by windage.
—
I
—
.23
.28
.32
.37
.42
.46
.51
.56
0.68
0.81
0.93
1.06
1.18
1.31
1.44
0.80
t196
1.12
1.29
1.45
1.62
1.78
1.95
2.38
2.80
3.24
3.68
4.12
4.57
5.02
1.50
1.80
2.10
2.40
2.71
3.02
3.33
3.64
4.43
4.24
6.05
6.87
7.70
8.53
9.37
Horsepower Rang
2.16 3.11 4.03 4.66
2.59 3.73 4.83 5.99
3.02 4.35 5.64 7.43
3.45 4.98 6.45 8.96
3.90 5.62 7.27 10.5
4.34 6.26 8.11
11.7
4.79 6.90 8.94 12.9
5.24 7.55 9.78 14.1
6.38 9.20 11.9 17.2
7.54 9.20 14.1 20.3
8.71 12.5 16.3 23.4
9.89 14.2 18.5 26.6
11.1 16.0 20.7 29.8
12.3 17.7 22.9 33.0
13.5 19.4 25.2 36.3
—
3.03
3.89
4.82
5.83
6.88
7.99
9.16
10.4
13.6
17.2
21.0
25.1
29.4
33.9
38.6
2.17
2.79
3.45
4.17
4.92
5.72
6.55
7.43
9.76
12.3
15.0
17.9
21.0
24.2
27.6
1.72
2.21
2.74
3.31
3.91
4.54
5.20
5.89
7.75 IV
9.76
11.9
14.2
16.7
19.2
-
3/4 Inch Pitch Sta dard Single-Strand Roller Chain No. 50 (Cont.)
No. of
Revolutions per Minute Small Sprocket
Teeth
iö ôô W öJ1Ô 1500 1800 [zoo[
—
—
mat
25
30
33
40
45
50
55
60
—
II
—
0.45
0.54
0.63
0.72
0.81
0.90
1.00
1.09
1.33
1.57
1.81
2.06
2.30
2.56
2.81
3/4 Inch
No. of
Teeth
I 50
Small
Sprkt.
11
0.78
13
093
15
1.08
17
1.24
19
I 1.40
21
1.56
23
1.72
25
1.88
30
2.29
33
2.70
40
3.12
45
II 3.55
50
3.97
55
4.40
60
4.84
Type IV. Oil Stream Lubrication: The
lubricant is usually supplied by a
circulating pump capable of supplying
each chain drive with a continuous stream
of oil. The oil should be applied inside the
chain loop evenly across the chain width,
and directed at the lower strand.
Consult chain manufacturers when it
appears desirable to use a type of
lubrication other than that recommended.
—
The extreme right portion of the tabulated
data is shown in boldface. This represents
ratings in the galling range. For optimum
results, it is recommended that the roller
chain
manufacturer be given the
opportunity of evaluating conditions of
operation if these horsepower ratings apply.
27
—
Horsepower Rating
Sprkt.
11
13
15
17
19
21
Type III. Bath or Disc Lubrication: With
bath lubrication the lower strand of chain
runs through a sump of oil in the drive
housing. The oil level should reach the
pitch line of the chain at its lowest point
while operating. With disc lubrication, the
chain operates above the oil level. The
disc picks up oil from the sump and
deposits it onto the chain, usually by
means of a trough. The diameter of the
disc should be such as to produce rim
speeds between 600 fpm minimum and
8,000 fpm maximum.
—
0.84
1.07
1.17
1.34
1.51
1.69
1.86
2.04
2.42
2.93
3.38
3.84
4.30
4.77
5.25
2.25
2.70
3.15
3.60
4.06
4.53
5.00
5.47
6.66
7.86
9.08
10.3
11.6
12.8
14.1
3.55
4.26
4.97
5.69
6.42
7.15
7.89
8.63
10.5
12.4
14.3
16.3
18.2
20.2
22.2
6.07
7.26
8.48
9.70
10.9
12.2
13.4
14.7
17.9
21.2
24.4
27.8
31.1
34.5
37.9
7.86
9.42
11.0
12.6
14.2
15.8
17.4
19.1
23.2
27.4
31.1
36.0
40.3
44.7
49.1
7.44
9.56
11.9
14.3
16.9
19.3
21.3
23.3
28.4
33.5
38.7
43.9
49.2
54.6
59.9
5.58
7.17
8.89
10.7
12.7
14.7
16.9
19.1
25.1
31.7
38.7
46.2
54.1
62.4
71.1
4.42
5.67
7.03
8.48
10.0
11.6
13.3
15.1
19.9
25.1
30.6
36.5
42.8
49.3
56.2
3.62
8
4.65
5.76
6.95
8.22
9.55
10.9
12.4
16.3 IV
20.5
25.1
29.9
35.1
40.5
46.1
Pitch Standard Single-Strand Roller Chain No. 60
Revolutions per Minute Small Sprocket
I 100 200 500 I 700 I 900 1200 1400 1600 I 1800
—
—
Horsepower Rating
1.44
1.72
2.01
2.30
2.60
2.89
3.19
3.49
4.25
5.02
5.80
6.90
7.38
8.18
8.99
2.69
3.22
3.76
4.31
4.86
5.41
5.97
6.53
7.95
9.40
10.90
12.3
13.8
15.3
16.8
6.14
7.34
8.57
9.81
11.1
12.3
13.6
14.9
18.1
21.4
54.7
28.1
31.5
34.9
38.3
8.32
9.96
11.0
13.3
15.0
16.7
18.4
20.2
24.6
29.0
33.5
38.1
42.7
47.3
51.9
10.5
12.5
14.6
16.7
18.8
21.0
23.2
25.4
30.9
36.5
42.1
47.8
54.0
59.4
65.3
11.9
15.30
18.9
21.7
24.4
27.2
30.0
32.9
40.0
47.3
54.6
62.0
69.5
77.0
84.6
9.45
12.10
15.0
18.2
21.5
24.9
28.6
32.4
42.6
53.6
62.7
72.2
80.0
88.4
97.2
7.70
9.89
12.3
14.8
17.5
20.3
23.3
26.4
34.7
43.7
53.4
63.7
74.6
86.1
98.1
6.49
8.34
10.3
12.5
14.70
17.10
19.6
22.5
29.2 IV
36.9
45.0
53.7
62.9
72.6
82.7
CHAPTER 3- POWER TRANSMISSION EQUIPT., PRIME MOVERS, MACHINES AND MACHINE PARTS
1 Inch Pitch Standard Single-Strand Roller Chain — No. 80
Revolutions per Minute — Small Sprocket
12515011001200130014001500170019001100011200114001
Horsepower Rating
23061491t8lII
[.80 .366.28904 t73
29.1 25.2 19.2 15.2
.03 7.51 10.8 4.0 17.1
13
34.0 31.2 23.8 18.9
j2.52 .70 8.77 2.6 6.4 20.0
15
38.9 37.6 28.7 22.7
2.88 .38 10.0 4.5 18.7 22.9
17
43.8 44.5 33.9 26.9
1 25.8
j3.25 .07 11.3
19
48.9 51.7 39.4 31.2
28.8
j3.62 .76 12.6
21
F
53.9 59.2 45.1 35.8
31.7
4.0 7.46 13.9
23
59.0 59.2 45.1 35.8 IV
34.6
4.38 17 15.2
25
71.8 78.9 67.2 53.3
423
j5.33 .94 18.5
30
84.8 93.3 84.7 67.2
50.0
16.29 1.7 21.9
33
98.0 108 103 82.1
47. 57.7
17.27 3.6 25.3
40
111 122 123 98.0
58. 65.5
18.25 5.4 28.7
45
125 137 145 115
60. 73.5
50 II j9.25 17.3 32.2
66.6 81.4 110 138 152 167 132
110.2 19.1 35.7
55
1 1/4 Inch Pitch Standard Sinqie-Strand Roller Chain No. 100
No. of
Revolutions per Minute — Small Sprocket
I 10 I 25 I 50 I 100 200 I 300 I 400 I 500 I 600 I 700 I
HorsepoRatingg
.2!sL - —
0.78 1.44 2.69 6.14 8.32 10.5 11.9 9.45 7.70 6.49
11
0.9 1.72 3.22 7.34 9.96 12.5 15.3 12.1 9.89 8.34
13
14.6 18.9 15.0 12.3 10.3
1.0 2.01 3.76 8.57 11
15
1.24 2.3 4.31 9.81 13.3 16.7 21.7 18.2 14.8 12.5
17
I 1.4 2.6 4.86 11.1 15 18.8 24.4 21.5 17.5 14.7
19
27.2 24.9 20.3 17.1
2.89 5.41 12.3 16.7 21
21
28.6 23.3 19.6
30
3.19 5.97 13.6 18.4 23.2
23
3.49 6.53 14.9 20.2 25.4 32.9 32.4 26.4 22.5
25
42.6 34.7 29.2 IV
40
4.25 7.95 18.1 24.6 30.9
30
5.02 9.40 21.4 29 36.5 47.3 53.6 43.7 36.9
33
45
5.80 10.9 24.7 33.5 42.1 54.6 62.7 53.4
40
72.2 63.7 53.7
62
6.90 12.3 28.1 38.1 47.8
45
74.6 62.9
80
69.5
7.38 13.8 31.5 42.7 54
50
88.4 86.1 72.6
77
4.4 8.18 15.3 34.9 47.3 59.4
55
4.8 8.99 16.8 38.3 51.9 65.3 84.6 97.2 98.1 82.7
60
Note: C= 5/9 (F-32)
mis = ft/mi,, x .00508
—
No. of 1
1
—
—
—
:
-
-
1 1/4 Inch Pitch Standard Sinole-Strand Roller Chain No. 100
Revolutions per Minute — Small Sprocket
25 I 50 110012001300140015001600 170018001 900 I
10
Horsepower Rating
s!S.
3.45 6.44 12.0 17.3 22.4 27.4132.3 37.1 32.8 27.5 III
11 — 0.81
4.13 7.22 14.4 20.7 26.9 32.8138.7 445 42.1 35.3
13
0.97
4.82 9.00 16.8 24.2 31.4 38.3145.2 51.9 52.2 43.7
1.13
15
5.52 10.3 19.2 27.7 35.9 43.9151.7 59.4 63.0 52.8
1.30
17
5.23 11.6 21.7 31.2 40.5 49.5158.3 67.0 74.4 62.3
1.46
19
5.94 11.9 24.2 34.8 45.1 55.1164.974.684. 72.4
1.63
21
7.65 14.3 26.6 38.4 49.7 60.8171.7 82.3 92.8 83.0
1.80
90.1 102 94.1
3.37 15.6 29.2 42.0 54.4
1.97
25
110 124 J
0.2 19.0 35.5 51.2 66.3
2A0
30
2.0 22.5 41.9 60.4 78.3 H13 130 146 156
33
2.83
3.9 26.0 48.4 69.8 90.4 111 130 150 169 188
40
3.27
3.71 8.47 5.8 29.5 55.0 79.3 103 126 148 170 192 213
45
4.16 9.49 7.7 33.061.688.8 115 141 166 190 215 239
50
4.61 10.5 19.6 36.6 68.3 98.4 128 iJj84 211 238 263
55
60 II 5.07 11.6 21.6 40.2 75.1 108 140 iJ02 231 261 290
No. of
11
13
15
17
19
21
23
25
30
33
40
45
50
55
60
-
—
-
-
-
-
-
-
-
.
-
120
800
I
37.9
48.7
60.4
72.8
86.1
100
115
130 IV
171
215
263
314
363
384
351
Roller Chain — No. 120 (Cont.)
Revolutions per Minute Small Sprocket
19001100011 1oc412ocl11300114001150011600117001 1800 I 1900 120001
Horsepower Rating
SnrI
3116.4 14.8 13.4 12.2 11.2 10.4 9.60
37.8 27.1
11
.5j21.0 19.0 17.2 15.7 14.4 13.3 5.20
40.8 34.9
13
50.6 43.2
i[2’.1 23.5 21.2 19.5 17.0 16.5
15
.2]31 5 28.4 25.8 23.5 21.6 §Z
61.0 52.1
17
2 33.5 30.4 27.8
.
37
•gp
72.1 61.6
19
10.5
83.8 71.6
21
96.1 82.0
23
IV
.7 56.1150.6 45.9117.7
25 IV 109 92.9
a7Al365 1671
143 122 1oiIE9
30
180 154 134 117 104 92.9119.2
33
220 188 163 143 112 27.21
40
263 225 195 136 42.1
45
339 259 167 65.2
50
—
302 266 97.3
55
—
252 139 12.0
60
1
f
11/’ Inch Pitch Standard Single-Strand Roller Chain No. 100 (Cont.
Ff
Revolutions per Minute — Small S rocket
11000111001120011 300I140011600I1800j2000122OC2400125001 2600 I
Horsepower Rating
Sork
114.2 11.6 9.71 8.30 7.20 6.30 5.90 5.60
III 23.4
11
‘18.2 14.9 12.5 10.6 9.20 8.10 7.60
30.1
13
37.3
15
.?45 18.4 15.5 13.2 11.4 10.0 1.70
15.9 13.8 12.1
4.3
45.0
17
I
) 8.8 16.3
tO.5
53.2
19
21.9 19.0
.JT3 30.11
t7.0
61.8
21
20.4
53.9 7.jE3E J
70.9
23
IV
31.1
.Iä5l39i
80.3
25
iv
30.31
106
30
i
1
33
133 115 101
163 141 124 11
40
194 168 148 135 117156.
45
—
227 197 173 153 137
50
262 227 199 151 58
55
299 259 168 68.0
60
-
Inch Pitch Standard Single-Strand Roller Chain — No.
Revolutions per Minute — Small Sçket
I 10 125 I 50 11001150 1200130014001500 600 700 I
III
Horsepower Rating
54.5 46.3
1.37 j2 10.9 15.6 20.3
45.3I5.4 65.3 59.5
13 18.7 24.3
1.64
76.1 73.8
1.9128.3
1.91 .36 8.13
87.2 89.0
5.0 32.4
2.19 .99 9.31
98.3 105
68.2j3
S.22
247 .62 10.5
110 122
31.4 40.7
I 2.75 .27 11.7
83.91j03 121 139
34.7 45
3.03 .92 12.9
38.0 49.2
9t81112 132 152
3.32 7.57 14.1
.‘°°
185
112 137 161
4.04 .221
54670.7 102 132 161 190 218
4.77
5.1 81.7 118 153 186 220 252
5,51
5.26 14.3 26.6 49.7 71.6 92.8 134 173 212 249 286
v.01 16.0 29.8 55.7 80.2 104 150 194 237 280 322
7.77 17.7 13.1 61.8 89.0 115 166 215 263 310 356
3.58 19.6 36.5 68.2 98.2 127 183 237 290 342 390
1/
—
No. ot
-
—
‘/2
Inch Pitt-.h
°“-‘-°‘=“
—
-
-
-
.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
—
-
-
-
-
-
-
28
-
CHAPTER 3- POWER TRANSMISSION EQUIPT., PRIME MOVERS, MACHINES AND MACHINE PARTS
r
1 3/4 Inch Pitch Standard Single-Strand Roller Chain
No.ot
Revolutions per Minute Small Sprocket
50 looIlSol200l25oI300I35oI 400 I
Horsepower_Rating
2174.8 9.06116.9 4.4 31.5 38.6 45.5 522 58.9
2.5
10.9120.3 9.2 37.8 46.2 54.5 62.5 70.5
2.9C
12.7 23. 34.1 44.1 54.0 63.6 73.1 82.4
14.5 27.
50.5161.71 P 83.6 942
3.8
180 30.
,j70.Gi t.1 94.3 106
4.2
18.2 34.C
3.4 776 91.4 105 118
4.7’
20.1 37.t
0.0 85.6 101 116 131
5.1
22.0 41.1
6.6 93.7 110 127 143
a’—
62
50f
7
114 134 154 174
7.4a,
31.6I5.1
110 135 159 182 206
.59
3T.2
127 156 183 211 238
.76
41.5 77.5 112 144 177 208 239 270
II
10.9]24.9 46.5 86.8 125 162 198 233 268 302
12.1127.6 51.5 96.2 139 179 219 259 297 335
13.3130.456.6 106 152 197 241 284 326 368
-
I
sg,
11
13
15
17
19
21
23
25
30
33
40
50
55
60
—
10
I
No. of
Teeth
No. 140
—
25
I
-
-
-
‘“
,..
I
450
500
65.5
78.4
91.6
105
118
132
145
159
194
229
264
300
336
372
396
720
86.2
101
115
130
145
160
175
213 IV
251
290
330
370
362
329
11
13
15
17
19
21
23
25
30
33
40
45
50
55
60
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
—
-
-
-
—
.
:
-.
—
—
inch Pitch Standard Sinale-Strand Roller Chain No. 160 (Cont.)
Revolutions per Minute— Small Sprocket
1550 1600 1650 1700 1750 1800 1850 1900 Ii 00011100 11200 11300 I
omal
Horsepower Rating
11
J1 73.5 65.2 58.3152.6 47.7 43.6 40.0 34.1 29.6 26.0 23.0
13
[108 94.4 83.7 74.9j67.5 61.3 56.0 51.4 43.9 38.0 33.4 18.4
15
[i 117 103 92.8183.7 76.0 69.4 63.7 54.4 47.1 41.4 7.4
17
[161 141 125 1121101 91.7 83.7 76.8 65.6 56.9 42.8
19
[i 166 148 1321119 108 98.990.877.5 67.2 31.7
21
194 172 1541138 126 115 105 90.1 76.7 17.3
23
[ö 222 197 1761159 144 131 121 103 66.2
25 IV 251 223 gj 180 163 149 137 117 52.5
IV
30
F 330 293 262 236 215 196 168 90.7 4.7
33
351 325 295 262 24 184 140 44.2
40
I 359 326 2ää’246 200 150 96.8
45
392 356 315 269 217 161 101 37.3
387 343 293 237 175 109 37.7jZ
L
L 372 315 259 192 120 42.2
348 285 214 136 51.6
Lc
Fii: °C = 5/9 (°F 32)
[ = ft/mm x .00508
—
—
-
Single-Strand Roller Chain No. 160
‘s per Minute Small Sprocket
110 ITo 1100l1501200125013001350! 400 I 450 I 500 I
Horsepower Rating
3.07 7.02 13.1 24.4 35.1 45.5155.6 65.5 75.3 84.9 94.8 96.6 III
3.67 8.42 15.7 29.2 42.0 54.4166.6 78.4 90.1 102 113.3 124
4.28 9.86 18. 34.1 49.0 63.5177.7 91.5 105 119 131 145
4.90 11.2 20. 39.0 56.1 72.7188.9 105 120 136 150 167
I
.5312.723. 44.a63.282.oI100 118 136 153 170 188
.16 14.1 26. 49.0 70.5 91.41112 132 151 171 189 209
.80 15.6 29. 54.1 77.7 jjJj23 145 167 188 208 231
7.44 17.1 31.
135 159 183 206 228 257
85.1
.06 20.2 38.7 ‘2. 104 134 164 193 212 251 277 307
0.724.545.
122 159 194 228 263 296 338 363
2.4 28.3 52.t
141 183224 264 304 342 380 410
II 4.0 30.1 59.9 111 160 20j 254 300 345 389 430 421
5.736.067. 125 180 23285 336 386 439 453 424
17.4 40.0 74.4 139 199 258 316 372 405 483 455 418
9.1 43.9 81.8 152 219 284 347 409 4151 484 449 403
P
.
2
/4 Inch Pitch Standard Single-Strand Roller Chain No. 140 (Cont.)
Revolutions per Minute Small Sprocket
Teeth
550 1600 1700 1800 1900 11 000111001120011 3001 1400 11500 1600 I
Horsepower Rating
11 III 75.1165.8 52.4 42.9 35.9J_ 26.6 23. 20.7118.5 167 15.2
13
93.9 84.6 67.3 55.1 46.21 34.2 30. 26.6 23.8 21.5 10.8
15
105 83.4 68.3 57.2E 42.4 37. 33.0 29.5 26.6
17
126i100 82.4 69.11
51.144 39.8 35.6 24.0
19
149 1119 97.4 81.6 60.4 53.0 47.0 42.1 8.6
21
171 138 113 94.8
70.2 ru 6 4.5 45.6
23
188 158 129 108
80.4 70.6 2.6 27.1
25
206 179 147 123
91.1 80.0 70.1 7.0
IV
30
251 236 193 161 [i38 119 96.1 21.6
33
274 295 297 243 204 174 129 44.8
40
316 342 363 297 249 171 77.5
45
349 387 381 308 221 120 7.8
50
30 405 367 278 173 53.7
55
96 388 342 236 111
60
306 306 180 35
No. 01
2— mcli Pitch
-
-
-
-
-
-
-
—
29
-
-
-
-
-
-
-
-
-
-
-
CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
Chapter 4
MACHINE GUARDS AND SAFETIES
AT POINTS OF OPERATION AND
DANGER ZONES
Impulse Metal Working Machines consists of hot
or cold process machines utilizing energy directly from
the prime mover, or from a mechanical storage device
onto a ram through a transmission and control system
that releases this energy in short bursts or power
strokes.
Section 1.0 Scope
—
This chapter covers provisions for the protection of
machine operators against hazards at the points of
operation of machines. It includes provisions for safe
use, design and guarding of points of operation and
danger zones for machinery utilized in various
industries. Provisions of this chapter shall not be
interpreted as alternatives to those described in other
chapters of this code.
Interlocked Gate Guard a guard or gate barrier at
the front or sides of the point of operation which is
interlocked or connected to a tripping device which will
prevent operation of the machine until the hand or
hands of the operator have been removed from the
danger zone.
—
Section 2.0 Definitions
machine capable of shearing metal
Plate Shear
stock more than 6mm thick
—
Danger Zone and area of place near or at the point
those in process in the machine may come in contact,
or be caught by or between moving and! or stationary
parts of the machine. This includes areas where
materials or stock are fed into, processed and/ or
discharged from the machine.
—
Point of Operation— the portions or areas of a
machine in which mechanical operations on the stock
or materials are performed. Such points of operations
shall necessarily include stock feeding and discharge
points on the machine.
Doctor Feeds a device employed to keep feed and
stock rolls clean and assist in feeding stock into the inrunning or feed rolls on the machine. It usually
consists of curved steel plates mounted in front of, and
leading to each pair of rolls. This plates extends
throughout the length of the rolls with its concave side
toward the rolls and its opposite edge held by spring or
gravity action against the surface of the top rolls.
—
motor-driven machines fitted with
Power Press
purposes of blanking, trimming,
for
rams or dies
stamping, forming or assembling
punching,
drawing,
materials.
—
A
Pull-Out Protective Device (Hand Fed).
mechanically operated device attached to the
operator’s hands, wrist or arms which withdraws the
operator’s hands from the danger zone as the ram
descends.
Drop Hammer a heavy metal cylinder or hammer
which is raised a practicable height and dropped so
that the force or energy of the blow is developed
entirely from gravity.
—
the reciprocating machine part within a
Ram
cylinder. It may also be called plunger, slide or
mandrel.
—
Foot and Hand Press machines actuated by foot or
hand power only, and fitted with rams or dies for
purposes of blanking, trimming, drawing, punching,
stamping, forming or assembling cold worked
materials.
—
Sweep Guards a mechanically operated guard that
sweeps the hands of the operator out of the way of the
descending ram.
—
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CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
Section 3.0 General Requirements
e.
The provisions herein described are classified
according to its applicability with the respective
machine processes or operations, thus:
Class A designation denotes that the specified rule or
provision applicable to all kinds of work or operations
involving said machines.
f.
Class B designations denotes that the specified rule
or provision may be satisfied by equivalent provisions
or adaptations for safely subject to considerations on
the nature of the work, materials, process, or industry
involved.
g.
3.1
h.
Automatic Feed. A feed of such character
i.
Semi-Automatic or Mechanical Feed.
When stock is fed under the ram using
machine actuated or detachable feed device
which do not necessitate that the operator’s
hands to enter the danger zone, there shall
be provided a guard, enclosure, or barrier in
front of the ram. Such feed devices may
include dial feed, slide-feed, push-feed,
rotating feed or other similar system.
c.
Limited Ram Travel (Hand Fed). The
machine shall be so arranged that the
maximum distance traveled by ram is not
over 10 mm.
d.
Ram Enclosure (Hand Fed). A fixed guard
or enclosure entirely surrounding the bottom
of the ram through every point of its travel
shall be so arranged that the operator’s
finger cannot go under the ram while the
press is in operation. There shall be no
shear between the top of the guard and any
part of the ram. The guard may be hinged or
otherwise adapted for ready removal for
purposes of repair or adjustment.
Pull-out Protective Device (Hand Fed). A
Two Handed Trip Device (Hand Fed).
This arrangement requires the simultaneous
and continuous action of both hands to
actuate the press.
that the services of an operator are not
required except at intervals to restock the
feeding device or magazine. When this type
of feed is used, the danger zone shall be
completely closed.
b.
Sweep Guard (Hand Fed). A sweep guard
is a mechanically operated guard that
sweeps the hands of the operator out of the
way of the descending ram. Such guard
should be padded to prevent injury should it
strike the operator’s wrist.
mechanically operated device attached to
the operator’s hands, wrist or arms which
withdraws the operator’s hands from the
danger zone as the ram descends.
Power, Foot and Hand Power Presses.
Power, foot and hand presses shall be guarded
in one or more ways enumerated below. The
points of operation other than those listed below
will be acceptable, provided they afford at least
equal protection for the operator.
a.
Interlocking Gate Guard (Hand Fed). A
guard or gate barrier at the front or sides of
the ram may be interlocked to a tripping
device which will not permit the press to
operate until the hand or hands of the
operator have been removed from the
danger zone.
3.2
Fixed Guard Across Front and Along
Sides (Hand Fed). A fixed guard or
enclosure across the front and along both
sides of the ram, so arranged that a finger or
fingers cannot go under, over, through, or
around the guard or enclosure while feeding
stock. Such a guard may be an integral part
of the die.
Squaring Shears (Class A). Mechanicallydriven foot or hand activated squaring shears
shall be provided with a guard which will prevent
the hands of the operator from entering the
danger zone where the knives or shears
traverse. This guard may be a fixed barrier, set
no more than 10 mm above the table; or a self
adjusting barrier no more than 10 mm above the
table, but which will automatically rise to the
thickness of the material.
a.
31
Automatic clamps of “hold-downs” on
squaring shears, with its openings protected
with plastic mesh or screen, may be
acceptable as suitable machine guards.
Hydraulic
or
pneumatic
hold-downs
however, shall be provided with a suitable
means of protection such as U-shaped
finger guards coming down not more than
10 mm from the table. Other equivalent
methods of guarding may be subject of
consideration by the mechanical engineer.
b.
c.
between the
material being cut exceeds 10 mm.
Photoelectric Guard systems may consist of
beams of light over the perimeter of the
danger zone. When such beam is broken or
blocked by any part of the operator’s body,
an emergency stop mechanism is actuated.
c.
Squaring shears guarded by means of strips
of heavy metal in front of the knife should be
set at such an angle so that the knife cutting
line will be visible to the operator.
3.3
Metal Embossing Machines (Class B). Metal
embossing machines shall be guarded at the
point of operation in the same manner as power
presses or rolls, or shall be provided with a feed
mechanism which will not require the operator to
come into contact with the die.
3.4
Non-Repeat Device (Class A). Hand-fed power
presses shall be so designed that the treadle or
lever shall disconnect from the clutch
mechanism after each stroke. A second device
shall automatically lock the clutch mechanism so
that the press cannot make a second stroke until
the treadle or hand lever is reset to its “ready”
position.
Exceptions:
1. Saws used for cutting hot metal and saws
with peripheral speed of less than 152
rn/mm.
2. Stereotype Saws, electrotype saws and
similar saws and used for cutting zinc,
copper or brass plate, or soft metals. If a
plate glass shield or similar barrier is
provided above the saw, the same shall be
so placed as to afford protection to the
operator.
3. The exposed parts of the saw blade under
the table shall be guarded.
3.7
The non-repeat device may not be rendered
inoperative unless proper instruction and
authorization is given by the employer to the
operator in order to permit continuous operation
of the press. Suitable fixed guards, warning
devices and signs shall be provided whenever
the press is in continuous mode.
3.5
3.6
Treadle Guards (Class A). A treadle on every
foot controlled power press shall be protected by
means of a guard designed to prevent
accidental tripping. For treadles other than long
bars extending across the machine, the
openings in such guards shall not be more than
twice the width of the foot.
Rolls (Class B):
a.
The in running side of the rolls shall be
provided with a fixed or self-adjusting barrier
so arranged that the material can be fed to
the rolls without permitting the fingers of the
operator to be caught between the rolls or
between the guard and the rolls.
b.
The control device shall be of the constant
contact type and shall be so located as to
prevent the employee from contacting the
danger zone, or
c.
The prime mover shall be equipped with an
effective brake and there shall be installed
across the front of the rolls at approximately
knee height a control bar, lever, or other
device which when actuated will stop the
motor and apply the brake.
Circular Metal-Cutting Saws (Class B):
a.
Circular metal-cutting saws shall be
provided with a hood that will cover the saw
to at least the depth of the teeth. The hood
shall automatically adjust itself to the
thickness of stock and remain in contact
with the material being cut at the point
where the saw engages the stock.
b.
There shall be a provided fixed or manuallyadjusted hood or guard when the space
If the material to be cut is in the form of
angles: i.e. T-bars, Z-bars, or other section
where the guard may not satisfy the
requirements of Section 4.3.6-a. and 4.3.6b; the saw may be covered with a
horizontally sliding guard, or an enclosure
with an opening through which the stock
may be fed.
3.8
Bar Stock Machine (Class A). On machine
where revolving bar stock is being machined,
that portion of the bar stock which extends
beyond the machine shall be guarded by a
trough or tube or by other effective means.
3.9
Wire Drawing Machines (Class B)
a.
32
Blocks shall be equipped with a stopping
device so arranged that it will automatically
I
CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
shut down the machine in case the operator
should be caught on the block and be
carried around it, or
b.
c.
3.14 Drop Hammers: Drop hammers shall be
equipped with safety stops which will hold the
hammer in the elevated position. Such stops
shall be of the pivoting type and shall be of such
a design that requires the hammer to be lifted to
release the safety stops.
A device along the operating side of a
continuous drawing frame or unit so
designed that pressure against the device
will instantly initiate the process of stopping
sequence of the machine.
Section 4.0 Die Casting Machines
4.1
Reels shall be equipped with stopping
device so arranged that it will automatically
shut down the block in case the operator
should be caught in the wires as it runs from
the reel, or in case the reel should be drawn
up to the frame.
3.10 Planners (Class A). Openings in the bed of all
metal planners shall be covered with substantial
metal or other suitable covering.
Hot Chamber Machine Controls. Every hot
chamber die casting machine shall be equipped
with one of the following controls:
a.
Two-hand
controls
requiring
the
simultaneous use of both hands until the die
is completely closed. Removal of either or
both hands during the closing of the die will
stop or reverse the closing cycle, or
b.
A single control of the constant pressure
type. This control shall be located at such a
distance from the parting line of the die that
the operator cannot reach into the die at the
parting line with his free hand. Removal of
the hand from the control during the closing
of the die will stop or reverse the closing
cycle, or
c.
A sliding gate guard which when closed will
prevent contact by the operator and the die.
This gate shall be interlocked with the
control system so that if the gate is opened
prior to the completion of the closing cycle,
the closing cycle will stop or reverse.
3.11 Alligator Shears (Class B):
a.
b.
The upper jaw of the shear shall be
surrounded with a heavy U-shaped metal
strip with the lower edge of the strap just far
enough above the cutting edge of the fixed
jaw to allow the material to be inserted
under it. The clearance from the moving jaw
shall not be over 76 mm, the width of the bar
should be great enough so that the tip of the
moving jaw does not rise above it.
A horizontal bar shall be secured to the
lower jaw, parallel to the cutting edge, at a
height sufficient to permit the passage of the
thickest stock, and so positioned to prevent
stock from bending or flying upwards.
4.2
3.12 Abrading, Buffing and Polishing Machines
(Class A):
a.
Exposed arbors shall be guarded.
b.
Arbor ends which are not equipped with a
coarse nuts or equivalent shall be guarded.
3.13
Cold Chamber Machine Controls. Every cold
chamber die casting machine shall be equipped
with one of the following controls:
a.
Two-hand
controls
requiring
the
simultaneous use of both hands until the die
is completely closed. Removal of either or
both hands during the closing of the die will
stop or reverse the closing cycle;
b.
A single control of the constant pressure
type. This control shall be located at such a
distance from the parting line of the die that
the operator cannot reach into the die at the
parting line with his free hand. Removal of
the hand from the control during the closing
of the die will stop or reverse the closing
cycle;
c.
A sliding-gate guard which when closed will
prevent contact by the operator and the die.
This gate shall be interlocked with the
Tumbling Barrels (Class A)
a.
Tumbling barrels shall be completely
enclosed or guarded by movable rail guards,
or by other suitable and effective means.
b.
If enclosed, tumbling barrels shall be
equipped with an effective lock or brake
mechanism.
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CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
control during the closing of the die will stop
or reverse the closing cycle.
control system so that if the gate is opened
prior to the completion of the closing cycle,
the cycle will stop to reverse:
d.
4.3
4.4
4.5
the
requiring
controls
Two-hand
simultaneous use of both hands until the die
is within 50 mm of complete closing. This
control shall have an interlocked limit switch
that maintains a closed circuit for the last 50
mm of the closing cycle. Removal of either
or both hands before the activation of the
limit switch will stop or reverse the closing
cycle.
Ladling Operation. To activate the plunger in
the shot sleeve a single control shall be
provided. This control shall be a type which
permits the operator to use his free hand for
ladling metal. The push button control shall be
so guarded by a shield or recessed so that it
cannot be activated by any part of the body
other than the finger.
b.
Every plunger on hot chamber machines
shall be equipped with a control interlocked
with the die which will prevent the operation
of the plunger prior to the closing of the die.
b.
Every plunger on cold chamber machines
shall be equipped with a control interlocked
with the die which will prevent the operation
of the plunger unless the die is completely
open or completely closed. Or for the
removal of a stuck plug, a cold chamber
machine may be equipped with two-hand
controls, which operate the plunger and
require simultaneous use of both hands.
Shields Between Die Casting Machine.
Shields shall be provided between die casting
machines to protect against metal spitting.
These shields shall be located at the parting line
of the die and shall be no less than 1 200 mm
wide and 1 830 mm high.
A fixed-barrier guard with controls. The
control may be foot-operated and shall be
interlocked with the primary control so that
the machine cannot be started while the
secondary control is activated. If the
secondary control is activated during the
closing cycle, the closing will stop or
reverse; or
4.7
Holding Furnaces. Any open holding furnace,
which measures less than 750 mm from the floor
or working level to the furnace top shall be
guarded by means of a ring guard around its
perimeter to a height of at least 750 mm from
the floor or working level.
A sliding-gate guard which when closed will
prevent contact by the helper and die. This
gate shall be interlocked with the primary
control system so that the machine cannot
be started while the gate is opened and
cannot be started until it is closed; or
5.1
Section 5.0 Wood Working Machine
c. Two-hand controls connected with the
primary controls and requiring simultaneous
use of both hands of the helper before the
machine can be started. Removal of one or
both hands during the closing cycle will stop
or reverse the closing cycle; or
d.
a.
4.6
Hot and Cold Chamber Machines, Helpers
Protection. Where a helper is employed, his
position shall be protected by:
a.
Plunger Control:
A single control of the constant pressure
type connected with the primary controls.
These controls shall be located at such a
distance from the parting line of the die that
the helper cannot reach into the die with his
free hand. Removal of the hand from the
34
Circular Rip Saw (Class B) Manual Feed:
a.
A hood shall be used that will cover the saw
to at least the depth of the teeth.
b.
Such hood shall automatically adjust itself to
the thickness of and remain contact with the
material being cut around point where the
stock encounters the saw; or
c.
The hood may be a fixed or manually
adjusted hood or guard provided the space
between the bottom of the guard and the
stock does not exceed 12.70 mm.
d.
The hood or other guard shall be so
designed as to prevent a kick-back. “Anti
Kick-Back” devices shall be designed to be
effective for all thickness of material.
CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
Recommendation: A pushing stick or
manual push rod of suitable design should
be provided for and used by the operator to
feed the short end of the stock through the
hood.
e.
f.
5.2
guard and the material being cut
does not exceed 12.70 mm.
Exception: Circular crosscut saws with
stationaiy table where the saw moves fotward
when cutting.
Except when grooving, a spreader shall be
provided and fastened securely at the rear
of saw in alignment with saw blade. It shall
be slightly thinner than the saw kerf and
slightly thicker than the saw disc.
Circular crosscut saw with stationary tables
where the saw moves forward horizontally
shall have a hood or guard securely
fastened to the table that will cover the saw
when running idle. The hood or guard shall
extend at least 50 mm in front of the saw
teeth when the saw is in its back position.
The width of the hood shall be limited so as
to provide not more than 12.70 mm
clearance on each side of saw blade. There
shall be adequate stops to prevent the saw
from moving beyond the edge of the table.
c.
The exposed unused parts of the saw blade
shall be guarded.
The exposed parts of the saw blade under
the table shall be guarded.
Self-Feed Circular-Ripsaw (Class A):
a.
A hood or guard shall be used to cover the
saw to at least the depth of the teeth. The
hood or guard need not rest upon the table
nor upon the stock, but shall extend to within
12.70 mm of the stock being worked.
b. The feed rolls or star wheels shall be
enclosed with a cover coming down to within
12.70mm of the stock.
5.4
Cordwood and Similar Saws (Class B). All
unused portions of the saw blade shall be
guarded.
c.
A spreader shall be fastened securely at the
rear of the saw in alignment with the saw
blade, except where a roller wheel is
provided at back of saw. The spreader shall
be slightly thinner than the saw kerf, and
slightly thicker than the saw disc.
5.5
Box Shock Cut-Off Saws (Class B). Box shock
cut-off saws shall be guarded either by a hood
or splitter-type guard. Either type guard shall
cover the top back quarter of the saw and shall
be kept adjusted close to the saw.
5.6
d.
The exposed parts of the saw blade under
the table shall be guarded.
Swing Cut-off Saw (Class A)
a.
e. Every self-feed circular ripsaw shall be
equipped with an anti-kick-back device
installed on the in-feed side. Such an antikick-back device shall be designed to be
effective for all thickness of stock.
5.3
b.
b. There shall be an effective device to return
the saw automatically to the back of the
table when released at any point of its travel
such device shall prevent saw from
rebounding and shall not depend on fiber
rope or cord for it to function.
Circular Crosscut Saw (Class B):
a.
A hood or guard shall be used to prevent
contact between the operator and the saw
teeth.
1.
The hood shall automatically adjust
itself to the thickness of and remain
in contact with the stock nearest the
point where cutting takes place; or
2.
The hood or guard may be a fixed
or manually adjusted provided the
space between the bottom of the
The saw blade shall be encased on both
sides in such a way that at least the upper
half of the blade and the arbor end will be
completely covered.
c.
35
If a counterweight is used, all bolts
supporting the bar and weight shall be
provided with nuts and cotter pins. A bolt
may be put through the exposed end of the
counterweight rod, where the weight does
not enclose the rod. A safety chain shall be
attached to the counterweight.
CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
5.7
5.8
d.
Limit chains or other positive stops shall be
provided to prevent the saw from swinging
beyond the front edge of the table.
e.
Where it is possible to pass behind a swing
cut-off saw the rear of the saw shall be
completely housed when the saw is in back
position. The housing shall include the
swing frame as well as the saw.
Portable Power Driven Circular Hand Saws
(Class A)
b.
c.
5.8
5.10 Horizontal Pull Saw (Class A), sometimes
referred to as “Contractor’s Saw” or “Radial Arm
Saw” shall be provided with the following:
Underhung Swing Cut-Off Saws (Class A).
The saw blade shall be fully enclosed when in
the extreme back position, and the swing frame
shall not pass the vertical position when at its
extreme forward limit. A positive stop shall be
furnished so that the saw cannot pass the front
edge of the table.
a.
Portable circular saw shall be equipped with
guards or hood which will automatically
adjust to the work when the saw is in use.
The guards are provided so that none of the
teeth above the work are exposed to
contact; and when the blade is withdrawn
from the work, the guard shall at least cover
the saw to the depth of the teeth. The saw
shall not be used without a shoe or guide.
The saw guards shall be equipped with a
handle or locked or blocked in an open
equipped with a handle or lug by which it
may be temporarily retracted without
exposing the operator’s fingers to the blade.
A hood shall be provided to cover the cutting
edge of the knife.
b.
The hood shall automatically adjust itself to
the thickness of the stock and remain in
contact with the stock does not exceed
12.70 mm.
c.
A fixed or manually adjusted hood or guard
may be allowed, provided the space
between the bottom of the guard and the
stock does not exceed 12.70 mm.
The saw blade shall be encased in such a
way that at least the upper half of the blade
and the arbor ends will completely be
covered.
b.
Limit chains or other positive stops shall be
used to prevent the saw from moving
beyond the front edge of the table. Such
limiting devices shall be so designed and
located that they can be easily inspected
and they shall be maintained in good
condition.
c.
Where a horizontal pull saw is used for
ripping purposes, there shall be an anti-kick
back device installed at the in-feed side.
Such a device shall be designed to be
effective for any thickness and the width of
the stock to be cut and shall not be attached
to the saw guard. Automatic feeding devices
when used they shall be guarded.
d.
There should be an effective device which
will return the saw automatically to the back
of the table when released at any point of its
travel; such a device shall prevent the saw
from rebounding.
a. All portions of the saw blade shall be
enclosed or guarded except that portion
between the guide rolls and the table. The
down travel guard from the upper wheel to
the guide shall be of an angle bar or channel
construction covering the front and at least
the outside of the blade, and shall be so
adjusted that the blade will travel within the
angle bar or channel.
Circular Knives
a.
a.
5.11 Band Knives and Band Saws (Class A).
(Including band re-saws having saw blades less
than 175 mm in width or band saw wheel less
than 1 525 mm in diameter) shall be guarded as
follows:
Saw guards shall not be locked or blocked
in an open position and shall be maintained
in good working condition at all times.
Circular Knives (Class A).
shall be guarded as follows:
The cutter blade under the table shall be
guarded.
d.
b. Band saw wheels shall be fully enclosed.
c. Feed rolls of band re-saws and band
ripsaws shall be protected with a semi
cylindrical guard to prevent the hands of the
36
CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
employee from coming in contact with the
in-running rolls at any point.
5.16 Elbow Sanders (Class A). The revolving head
shall be fully guarded except where abrasive
comes in contact with the material.
5.12 Jointer (Class A):
a.
b.
5.17 Boring and Mortising Machines (Class A):
All jointers shall be equipped with cylindrical
cutting heads.
A suitable guard which will automatically
cover the exposed portion of the cutting
head not engaging the stock shall be used.
The guard shall be capable of protecting the
entire length of the cutting space in the
table.
c.
The exposed portion of the cutting head at
the rear of the fence shall be covered.
d.
Where equipped with automatic feed, the
feeding mechanism shall be guarded.
e.
Where knives are exposed beneath the
table, they shall be guarded.
a.
Only safety-hit chucks with no projecting set
screws should be used.
b.
Boring bits should be provided with a guard
that will enclose all portions of the bit and
chuck above the stock.
c.
The top of the cutting chain and driving
mechanism on chain mortisers shall be
enclosed.
d.
Where counterweights are used, one of the
following measures, or equivalent means
shall be used to prevent the counterweights
from dropping:
Recommendations:
1. A safety pusher of suitable design should be
provided and used.
2. The operator must protective eyewear or
goggles and dust mask during operation of
the machine.
5.13 Belt Sanders (Class A). Belt sanders shall
have both pulleys and the unused run of the
sanding belt enclosed. Rim guards will be
acceptable for pulleys with smooth disc wheels
provided the in-running nip points are guarded.
Guards may be hinged to permit sanding on the
pulley.
b.
Feed rolls and pressure rolls shall be
enclosed except such parts as may be
necessary to feed stock.
2.
A bolt shall be put through the
extreme end of the bar, or
3.
The counterweight assembly shall
be equipped with nuts and cotter
pins.
5.19 Planers, Moulders, Stickers and Matches
(Class A), Shapers (Class B):
a.
Knife heads of wood shapers and cutting
heads of other machines, not automatically
fed, shall be provided with guards, or
templates, jigs, or fixtures which will enable
the part to be processed without exposing
the operator’s hands to the danger zone.
b.
Single cutter knives in shaper heads shall
not be used. Knives shall balance each
other by weight and shall be so mounted in
the heads as to revolve at full speed without
dangerous vibration. The back ends of the
knives shall extend at least to a point where
it makes a right angle with the axis of
spindle. When the knife extends a distance
equal to or greater than the gripped length
of the knife there shall be separate means to
secure the knife other than the friction
5.15 Drum Sanders (Class A):
The exposed parts of the drum except that
portion where the material comes in contact
with the abrasive surfaces shall be guarded.
It shall be bolted to the bar by
means of a bolt passing through
both bar and counterweight, or
5.18 Tenon Machines (Class A). Cutting heads and
saws of tenoning machines shall be guarded.
5.14 Disc Sanders (Class A). Disc sanders shall
have the periphery and back of revolving disc
guarded, and the space between revolving disc
and edge of table shall not be greater than 6.35
mm.
a.
1.
37
CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
and is so marked. The following table shows
maximum speeds for various diameter saws.
between the collar and the knife. Such
means may be a hook, a through bolt, slots
or serrations.
c.
fed
automatically
of
heads
Knife
woodworking machines such as stickers,
planers, molders, and matchers, shall be
guarded against contact. The feed rolls shall
be enclosed, except as may be necessary to
feed stock. The guard shall be fastened to
the frame carrying the rolls so as to remain
in adjustment for any thickness of stock.
Knives shall be so mounted in the heads as
to revolve at full speed without dangerous
vibration.
d.
Double-spindle shapers shall be provided
with a spindle starting and stopping device
for each spindle.
Table 4.5.23 Maximum Operating Speeds of Circluar Saws.
Pitch Diameter of Saw
(mm)
200
250
300
350
400
450
500
550
600
650
700
750
5.24 Wobble Saws. Wobble Saws shall not be used.
5.25 Exhaust Systems. Whenever the chips and
sawdust produced by woodworking machines
accumulate on the floor so as to endanger
employees, suitable exhaust system shall be
required.
..athes (Shoe Lathes, Spoke and
5.20 Automa
All Other Automatic Lathes of the Rotating
Knife Type) (Class A). A hood or cover shall
be provided to completely enclose the cutter
blades while the stock is being worked. Such
hood or cover may be of sheet steel and
provided with openings no larger than 10 mm in
any dimension.
5.21
Section 6.0 Paper and Printing Machines
6.1
Combination Woodworking Machines (Class
B). Each point of operation of all component
machines or tools shall be guarded as required
for each individual tool in a separate machine.
Such machines shall be equipped with a
separate starting and stopping device for each
point of operation.
5.22 Cracked Saws:
a.
Any band saw found to have developed a
crack whose length is greater than one-tenth
(1/10) the width of the band, shall be
replaced unless the width is so reduced so
as to eliminate the cracks or unless the
cracked section is repaired.
b.
Any circular saw that is found to have
developed a crack whose length exceeds
5% of the diameter of the saw shall be
discarded unless the diameter is so reduced
as to eliminate the crack and the tension is
corrected.
Max. Circular speed
(RPM)
5,732
4,586
3,821
3,275
2,866
2,547
2,292
2,084
1,910
1,763
1,637
1,528
Calendar and Similar Rolls (Class B). Each
calendar shall be equipped with a guard or
feeding device, so arranged that the material
can be fed without permitting the fingers of the
operator to be caught by the rolls. The device
shall be so arranged that the operator can
immediately stop the rolls, at the feed point, by
the use of a lever rod or treadle. The rolls shall
be equipped with an automatic trip device that
will stop the machine when the fingers approach
the intake points. “Doctor Feed” is acceptable.
Note: The so-called “Doctor Feed” can be used
on calendar stacks. It is a device employed to
keep the rolls clean and to assist in feeding the
material into the in-running side of each pair of
rolls on the stack. It generally consists of a
cunied steel plate attached in front of, and
leading to each pair of rolls. This plate extends
through the length of the rolls with its concave
side toward the rolls and its opposite edge held
by spring or gravity against the surface of the
top rolls of each pair just above the nip point on
the cut-running side.
In operation the material is fed into the top or
first pair of rolls of the stack and as it emerges, it
is guided by the curved plate of the doctor feed
into the next pair of in-running rolls; and so on
down the stack.
5.23 Maximum Speeds of Circular Saws. The
peripheral speeds of circular saws shall not
exceed 3 600 rn/mm unless the saw has been
manufactured or hammered for a higher speed
38
CHAPTER 4— MACHINERY DANGER ZONE AND POINTS OF OPERATION
6.2
Corner Cutter (Class A). Single and double
machines with or without mechanical power
shall be provided with a guard in front of and to
the side of knives.
6.3
Corner Stayers (Class A). Corner stayers with
or without mechanical power shall be provided
with an automatic device that will instantly stop
the downward motion of the plunger, should the
fingers of the operator come between the
plunger and the anvil.
6.4
Cutter and Creasers (Class A). Drum cylinder
type cutters and creasers shall be guarded so
as to prevent the operator’s hands being caught
between the cylinder and the bed.
6.5
Rotary Scoring Machines (Class A). Scorers
shall have guard in front of in-running discs that
will prevent injury to the operator’s hands while
the machine is in operation.
6.6
Drum Winder on Paper Machine (Class A).
Machine should be so arranged that the drums
run outward. Where the drums run inward on the
operating side a cover or guard shall be
provided for the point of contact between the
drum and the paper roll.
6.7
6.8
Index Cutter (Class B). All knives or plungers
used for cutting strips off ends of books and
similar operations shall be provided with a guard
that will prevent the operator’s hands from
coming into contact with the cutting knife or
plunger as it descends.
6.9
Power-Driven Guillotine Paper Cutters (Paper
Cutters). Power-driven guillotine paper cutters
shall be provided with:
a.
(Class A). A non-repeat device that will
automatically lock the clutch mechanism into
place so that the cutter cannot make a
second stroke until the hand lever is again
moved into the starting position, or
b.
(Class A). A buffer that will interpose a
positive stop to some moving parts of the
machine whenever the clutch fails to
perform the function of preventing the cutter
from making a repeat stroke. In addition to
the non-repeat device or buffer, such paper
cutters shall be provided with:
Job Platen Press (Class B). Job platen
presses with or without mechanical power shall
be provided with one of the following:
a.
An automatic feed which does not require
the operator’s hands to be placed between
the platen and bed, or
b.
An automatic feed which will prevent the
platen from closing if the hand or hands of
the operator are caught between the platen
and the bed, or
c.
d.
c.
A guard or gate, mechanically operated,
which will throw the operator’s hands out of
the way as the press closes. For sweep
guards which lift the hands out of the danger
zone, the guard should rise at least 100 mm
above the platen as the press closes, and
should descend by gravity or be drawn by
springs. The guard shall be so arranged that
it will prevent a shear between the guard
and the top of the platen, or
1.
(Class B). A-two-handed starting
device
which
requires
the
simultaneous action of both hands
during the cutting motion of the
knife, or
2.
(Class B). An interlocked starting
device that will interpose a barrier
to interlocking between the starting
levers and clutch which must be
released through a movement of the
hand starting lever before the lever
can be moved to the position where
it applies power to the cutter.
(Class A). Simultaneous operation of paper
cutters by more than one operator shall not
be permitted or required by the employer.
Exception: Continuous feed trimmers.
6.10 Paper Box Ending and Edge Attaching
Machines (Class A). Paper box ending and
edge attaching machines shall be provided with
an automatic device which will prevent the
application of injurious pressure if the fingers of
the operators are between the top of the form
and the pressure head.
Any other device or tripping mechanism
which will prevent the platen from fully
closing if the hands of the operator should
be between the platen and bed.
6.11 Cylinder and Rotary Presses (Class B). The
in-running sides of power-operated rollers or
cylinders shall be provided with a guard so
39
CHAPTER 4— MACHINERY DANGER ZONE AND POINTS OF OPERATION
b.
arranged that the material can be fed to the
roller without permitting the operator’s fingers to
be caught between the roller or cylinders.
6.12 Lithographic Presses (Class A). The inrunning side of the cylinder and roller shall be
provided with a guard that will prevent the
operator from being caught between the
cylinders.
Section 7.0 Textile and Laundry
Machinery
7.1
Shuttles (Class A). All looms shall have shuttle
guards or shall be constructed in such a manner
as to prevent the shuttle from flying off from the
machine.
7.2
Cards (Class A). The cylinder cover or
revolving flat type cards shall be provided with
an interlock, securely bolted in place; or shall be
provided with a stripping device so arranged that
the operator cannot come in contact with the
point of operation.
6.13 Embossing Machines (Class A). Embossing
machines of the head type shall be equipped
with:
a.
A fixed enclosing front and sides of press
with just enough clearance space for
feeding stock. The guard shall be so
arranged that the operator’s fingers cannot
be caught between the press and the die
while feeding stock, or
b.
A fixed or a movable front guard connected
to the operating mechanism in such manner
that the operator’s fingers cannot be caught
into the press while feeding stock, or
c.
A two-handed starting device which requires
the simultaneous action of both hands to
start the machine.
A licker-in cover shall be provided on all cards
and shall be bolted securely in place so that the
operator cannot readily open it. Thumbscrews
or wing nuts shall not be used.
7.3
Carpet Frayer or Rag Shredder (Class A).
Cylinder door or cover shall be provided with an
interlock so constructed that the cover cannot be
opened while the roller is revolving or the cover
shall be clamped in place and the slot be so
constructed and guarded that the operator’s
fingers cannot come in contact with the roller.
7.4
Carpet Trimmer (Class A). Revolving knives
shall be guarded.
7.5
Stationary Circular Knife (Class A). Circular
Knives or discs shall be equipped with a guard
that will prevent contact with the cutting edges
while the machine is in operation.
7.6
Cotton Picker, Opener and Willower (Class
A). The beater cover shall be provided with
interlocking device so arranged that the cover
cannot be opened while the beater is revolving.
7.7
Picker Machines (Class A). All machines used
in picking wool, hair, rags or other material shall
have the rolls completely covered, except the
opening necessary to feed stock. This opening
shall be constructed or guarded that the
employee’s fingers cannot come into contact
with rolls.
7.8
Pile Cutter or Shearer (Class A). Knife rolls
shall be provided with a cover of guard that will
Exception: Machines equipped with feeding
devices such that the hands of the operator
cannot come in contact with the die.
6.14 Paper Punches and Line Perforators (Class
B). Mechanical or foot power punches and line
perforators shall be provided with an effective
device that will prevent the operator’s fingers
from coming between the punch and die.
Exception: Paper punches and line perforators
where the clearance between the opening for
feeding stock does not exceed 10 mm in the
open position.
6.15 Slotters (Class A):
a.
Vertical Slotters
1.
The knife shall be provided with a
stripper; or
2.
It shall be provided with a guard in
front of the knives so arranged that
the hands of the operator cannot
come into contact with the knives
while machine is in operation.
Rotary Slotters. A guard shall be provided
in front of the knives so that the hands of the
operator cannot come into contact with the
knives while machine is in operation.
40
CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
prevent the employee’s fingers from coming in
contact with the rolls.
7.9
cylinders or shell open during loading or
unloading.
Napper (Class A). Rolls shall be provided with a
cover or guard so arranged that the employee’s
fingers cannot be caught in the rolls while
feeding the material.
c.
7.10 Silver and Ribbon Lap Machine (Doublers)
(Class A). A device or cover shall be provided
and so arranged that the employee’s hands
cannot be caught under the lap roll.
7.15 Centrifugal Extractor (Class A):
a.
Each extractor shall be equipped with a
metal cover at least 0.953 mm thick, or its
equivalent sturdiness, which shall entirely
cover the opening to the outer shell. The
cover shall be kept in its closed position
when the extractor is in motion.
b.
Each extractor shall be equipped with an
interlocking device that will prevent the
cover from being opened while basket is in
motion; and also prevent the operation of
the basket while the cover is open.
7.11 Garnet Machine (Class A). Openings in the
lower frame and between lower frames and floor
shall be guarded. Where metal guards are used,
it shall not be less than 0.953 mm thick.
7.12 Marking Machine (Class A).
a.
b.
c.
Each power marking machine shall be
equipped with a spring compression device
of such design as to protect the finger bones
should these be caught between the
marking plunger and platen, or
Note: This should not prevent the movement
of the basket by hand to insure an even
loading when the cover is open.
The marking machines shall be equipped
with a control mechanism which will require
the simultaneous action of both hands to
operate the machine, or
c.
No extractor shall be operated at a speed
greater than the manufacturer’s rating,
which shall be stamped on the basket where
easily visible in letters not less than 6 mm in
height. The maximum permissible speed
shall be given in revolutions per minute.
d.
Each engine prime mover individually
driving an extractor shall be provided with
an effective speed limiter or governor.
e.
The exterior of the basket including hoops or
bands shall be inspected at least every six
months to determine condition of basket.
The extractor shall be dismantled and the
bearings, bearing blocks and basket shall be
inspected at least once a year and all
necessary repairs or replacements made. If
basket shows signs of weakness, it shall not
be used.
f.
Each extractor shall be effectively, secured
in position on the floor or foundation so as to
eliminate unsafe vibration.
There shall be a guard that will interpose a
barrier in front of the marking plunger.
7.13 Textile Machines:
Recommendation: Operators designated to
Blow Room, Spinning, Weaving and part of
Finishing Departments must be provided with
suitable dust masks. Illumination of these
working areas shall be maintained at maximum
design levels.
7.14 Washing Machine (Class A).
a.
b.
Each washing méchine shall be equipped
with brake or other devices to prevent the
inner cylinder from moving while loading or
unloading.
Each front loading washing machine shall
be equipped with an interlocking device that
will prevent the inside cylinder from moving
when the outer door on the case or shell is
open; and it shall also prevent the door from
being opened while inside cylinder is in
motion.
7.16 Power Wringer (Class A). Each power wringer
shall be equipped with a guard across the entire
front of the feed or first roll so arranged that
when struck the machine will immediately stop.
Each washing machine shall be provided
with a safe and effective means for holding
the doors or covers of inner and outer
41
CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
a slot or hopper or a rod located directly in front
of the feed and extending the full length of the
roll.
7.17 Starching Machine (Cylinder or Box Type)
(Class A). Each starching machine shall have
the rolls or cylinders guarded so as to prevent
contact by the employees while the machine is
in motion.
Conventional
a.
Each drying tumbler shall be equipped with
an interlocking device that will prevent the
inside cylinder from moving when the door
on the case or shell is open. Such device
shall also prevent the door from being
opened while the inside cylinders is in
motion.
Each flat-work and collar ironer shall be
equipped with a guard across the entire
front of the feed or first pressure roles, so
arranged that when struck, the machine will
immediately stop.
b.
The pressure rolls shall be guarded or
covered so that an employee cannot be
caught or pulled into the rolls.
7.18 Drying Tumbler (Horizontal
Type) (Class A):
a.
7.21 Ironer (Flatwork Type) (Class A):
7.22 Ironer (Body Type) (Class A). Each body
ironer, shall be equipped with a guard across
the entire length of the feed roll or shoe, so
arranged that when struck, the machine will
immediately stop.
Note: This should not prevent the movement
of the inner cylinder under the action of a
hand-operated mechanism or under the
operation of an “inching” device.
b.
Each drying tumbler shall be provided with
adequate means for holding open the doors
or covers of inner and outer cylinders or
shells while being loaded or unloaded.
c.
Each drying tumbler shall be equipped with
brakes or other positive locking devices to
prevent the inner cylinder from moving
“Inching
during loading and unloading.
devices” are permitted.
7.23 Ironer (Rotary-body Type) (Class A). Each
combined rotary bosom and coat-ironer shall be
equipped with a guard across the entire length
of the feed roll or shoe, so arranged that when
struck, the machine will immediately stop.
7.24 Ironer (Press Type) (Class A)
or condition!ng
Shakeout
Exception:
tumblers where the clothes are loaded into
the open end of the revolving cylinder and
are automatically discharged out of the
opposite end.
a.
Each ironing press (excluding hand or foot
power presses) shall be equipped with a two
hand device which require the simultaneous
action of both hands to operate the press.
b.
Every power-driven ironing press of the type
used in the dry cleaning or garment
manufacturing industry shall be equipped
with two hand controls which will require the
simultaneous use of both hands to apply
heavy pressure or to look the press.
7.19 Shaker (Clothes Tumbler, Batch Type) (Class
A):
a.
b.
7.25 Laundry Machine. Working areas around the
Laundry Machine shall be provided with non
skid or slip-resistant flooring.
Each shaker or clothes tumbler shall be
equipped with a device that will prevent the
tumbler from moving while the door is open.
The tumbler shall be enclosed or guarded
so as to prevent accidental contact.
Section 8.0 Leather and Composition
Good Machines
Each shaker or clothes tumbler shall b€
equipped with brakes or other positiv.
locking devices to prevent the insid.
cylinder from moving when the machine
loaded or unloaded. “Inching devices” are
permitted.
8.1
Dinking and Clicking Machrnes (Class A).
Every dinking machine shall be guarded by at
least one of the following methods:
a.
7.20 Dampening Machine (Class A). The rolls on
dampening machines shall be guarded by either
42
“Safety type” dies shall be used throughout.
Dies of this type shall be at least 75 mm in
height provided with safety grooves or
flanges. This safety flanges reduce the
CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
danger of having the operator’s fingers
being caught between top of die and beam.
Other types are provided with horizontal or
vertical handles at least 65 mm in height
above the die proper; or
b.
c.
d.
8.2
8.3
The machine shall be provided with a sliding
table or swinging head which does not
require the operator to place his hands
under the beam or head; or
There shall be a two-handed device that
required both hands of the operator to be
removed from under the beam at the
moment of tripping the machine or operation
of the machine; or
The point of operation shall be guarded on
all sides. The end guards shall be fixed and
the front and back guards shall be gate
guards of the elevating interlocking type.
a simultaneous action of both hands, or they
shall be provided with a mechanical feeding
device.
b.
The plunger shall be guarded either by a
complete enclosure or by a barrier guard in
front of the plunger.
8.4
Skiving Machines (Roll Feed) (Class A). Feed
rolls shall be so arranged that material must be
fed through slot or under a fixed or removable
metal rod or strip directly in front of the feed and
running the full length of the rolls.
8.5
Splitter (Stationary Knife) (Class A). Feed
rolls shall be so arranged that material must be
fed through a slot or under a fixed metal rod or
strip directly in front of the feed and running the
full length of the rolls.
8.6
Splitter (Band Knife) (Class A)
Embossing Machines (Power or Foot Driven)
(Class A). Embossers of the head type shall be
equipped with the following:
a.
All exposed portions of the knife as well as
band wheels shall be enclosed and feed
rolls shall be guarded.
a.
A fixed guard enclosing front and sides of
platen with stock feeding slots too narrow to
allow insertion of operator’s fingers, or
b.
b.
An interlocking gate-guard connected with
the operating mechanism in such a way that
it will automatically protect front and sides of
platen during the power stroke in such
manner that the operator’s hand cannot be
caught by the platen, or
An extension of the stopping device shall be
installed across the entire front of the top of
the feed roll so installed that it can be readily
operated from the operator’s working
position.
8.7
Stripper (Class B). Strippers shall be provided
with control device which requires the
simultaneous action of both hands during the
cutting movement of the knife.
c.
An actuating device that requires the
simultaneous action of both hands of the
operator or operators, whenever more than
one person is required to operate the
machine.
8.8
Tanning Drums (Class A). Horizontal revolving
drums shall be guarded, in addition, the drum
shall be provided with a stopping device, to
prevent the movement of the drum while loading
or unloading.
d.
A sliding or revolving table or other feeding
device which does not require the operator
to place his hands under the platen, or
8.9
e.
A mechanically operated guard that throws
the hands of the operator out of the way as
the platen descends. Such a guard should
be padded to prevent injury should it strike
the operator’s hand or wrist.
Roll Type Machines (Class A). The in-running
side of corrugating, crimping, embossing,
pleating, printing, and graining rolls shall be
guarded.
8.10 Dehairing Machines (Class A). All knives used
in removing hair from hides and skins shall be
enclosed except such opening as is necessary
to feed stock.
Heel Compressing Machine (Class A)
a.
8.11 Fleshing and Dehairing Machines
Special
Types. All fleshing and dehairing machines in
which the cylinders have a secondary motion in
addition to a rotary one shall be equipped with a
—
Heel compressing machines shall be
equipped with a control device that requires
43
CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
be so located that the operator
cannot reach into the mixer while
pressing the button, or
two hand control. This control must be arranged
so that the simultaneous and continuous action
of both hands is required to set the machine in
motion.
2.
If belt driven, the belt shifter shall be
so arranged that it will normally
move the belt toward the loose
pulley and hold it there while the
mixer bowl is tilted and uncovered
unless the operator pushes the belt
lever toward the tight pulley. The
belt shifter must be so located that
the operator cannot reach into the
bowl while holding the shifter, or
3.
If clutch driven, the clutch lever shall
be so arranged that it will move the
clutch out of engagement and hold it
there while the mixer is tilted or
uncovered unless the operator
moves the clutch lever to engage it.
The clutch lever shall be so located
that the operator cannot reach into
the bowl while holding the lever.
8.12 Whitening Machines. The moving parts of the
heads of whitening machine shall be enclosed
except such opening as is necessary to feed the
stock.
Section 9.0 Food and Tobacco Machinery
9.1
9.2
9.3
Pressure Bottling Machine (Class A).
Pressure bottling machines shall be provided
with an enclosure made of sheet metal not less
than 1.27 mm thick or wire mesh with opening
not to exceed 6 mm, and shall be so arranged
on the machine to confine or safety deflect
broken glass. The enclosure shall extend
downward at sides and rear to a point level with
that part of the machine on which the bottle
stands while being filled and upward to a point
of at least 100 mm higher than the top of the
bottle and be so constructed that bottle side is
facing the operator. When the bottling is done
3
under a pressure of more than 0.053 kg/mm
not
metal
of
constructed
be
shall
enclosure
such
less than 2.799 mm thick.
Note: When a pushbutton control is
used, it is recommended that there
should be installed in the circuit a
loose fitting piston type inverse time
relay designed to open the circuit at
the end of one second operation.
Cake Center (Band Knife) (Class A). Band
wheels of band knives shall be completely
encased and all portions of the knives shall be
enclosed or guarded except for that portion
between the guide and the table where the saw
engages the stock. If metal guards were used, it
shall be of not less than 0.953 mm thick; or if
other material is used, the guard shall be of
equal strength and rigidity.
Exception: Mechanically fed and
discharged horizontal tilting type
dough mixers in inaccessible
locations.
9.4
Dough, Cakes or candy Mixers (Horizontal
Non-Tilting Dough Mixers Type) (Class A).
Horizontal non-tilting type dough mixers shall
have a cover with an interlocking device so
arranged that power cannot be supplied to the
agitators unless the cover is in place on the
mixer.
9.5
Dough Brake (Class A):
Dough or Candy Mixers (Horizontal Tilting
Dough Mixer Type) (Class A).
a.
b.
Horizontal tilting type dough mixers shall be
provided with a cover over the top of the
mixer. An interlocking device shall be
provided, so arranged that power cannot be
applied to the agitators unless the mixer is in
operating position, with cover in place.
The mixer when tilted shall be operated with
the covers were open.
1.
If equipped with an electrical
pushbutton that will require the
operator to keep his finger on the
button when operating the mixer
with the cover open; the button shall
44
a.
Rolls on dough brakes shall be guarded so
that the operator’s hand cannot come in
contact with the rolls when in motion, or
b.
There shall be installed a stop bar located
along the end of the dough table which,
when actuated, will automatically shut off
power and apply a brake to the rolls.
CHAPTER 4— MACHINERY DANGER ZONE AND POINTS OF OPERATION
9.6
9.7
Dividers (Class A):
a.
All pinch points and shear points from
reciprocating or rotating parts of the divider
shall be enclosed or guarded, to protect the
operator’s hands and fingers.
b.
Guards at the front of a divider shall be so
arranged that the weight of the dough can
be adjusted without removing the guard.
c.
The back of the divider shall have a
complete cover to enclose all the moving
parts, or each individual part shall be
enclosed or guarded. The rear cover shall
be provided with an electric switch so
arranged that the machine cannot operate
when this cover is open.
ci.
The oil holes in the knife at the back of the
divider shall be of such size that employee’s
finger cannot go through the hole.
9.8
9.9
Rotary Dough Kneaders (Class A).
a.
Each direct-driven rotary dough kneader
shall be equipped with a guard across the
entire length of the down-running side of
each corrugated kneading roll so arranged
and installed that if struck, the machine will
stop.
b.
All dough kneaders other than those directdriven shall be equipped with a guard
across the entire length of the down-running
side of each corrugated kneading roll and
shall be equipped with a device which will
quickly disengage the power. The means of
operating such a device shall be so located
and so arranged that the operator can
readily reach it from any working position.
Slicers and Wrappers (Class A):
a.
Where necessary to manually push the last
loaf through the slicing knives the operator
shall be provided with, and shall use a
suitable and adequate device by which the
loaf can be pushed through the knives
without danger to his hands or fingers.
b.
The cover over the knife head of
reciprocating blade slicers shall be provided
with an electrical control switch so that the
machine cannot operate unless the cover is
in place.
c.
On slicers with endless band knives, the
wiring for the motor shall be so arranged
that a brake will be applied each time the
motor is shut off, or it shall be so arranged
by means of a limit switch that cannot be run
with the side door open. All doors and
removable panels to the cutting heads shall
be either connected to electric switchers or
shall have no latch openings and be so
fastened that they cannot be opened from
the outside through the side door.
ci.
When it is necessary to sharpen blades on
the machine, a barrier shall be provided
leaving only sufficient opening to the
sharpening stone to reach the knife blades.
Moulders (Class A):
a.
b.
Mechanical feed moulder shall be provided
with hoppers so designed and connected to
the proofer that an employee’s hands
cannot go into the hopper where they will
come in contact with the in-running rolls.
Hand-feed molders shall be provided with a
belt-feed device or the hopper shall extend
high enough so that the hands of the
operator cannot get into the feed rolls. The
top edge of such a hopper shall be well
rounded to prevent injury when it is struck or
bumped by the employee’s hand.
c.
There shall be a stopping device within easy
reach of the operator who feeds the molder
and another stopping device within the
reach of the employee taking the dough
away from the molder.
d.
Where a removable crank is used to adjust
the molder for different sizes of loaf by
adjusting a nut on the molder drum,
brackets shall be provided on the side of the
machine for holding the crank when it is not
in use. The brackets should be connected to
a contact switch so that when the crank is
removed, the current is broken and the
machine cannot run unless the crank is
returned to rest on the bracket.
9.10 Candy Cutter (Roller Type) (Class A). The
rolls, or knives of roller and fan type candy
cutters, shall be provided with a cover or guard,
so arranged that the fingers of the operator
cannot come in contact with same. A safety bar
shall also be provided at the in-feed side.
45
CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
cover the hoper opening except for
openings in the grille and shall be
above the bottom of the pan.
9.11 Caramel Slitter (Circular Knife Type) (Class
A). The knives shall be completely covered with
an adjustable guard of sheet metal or wire mesh
(with openings not to exceed 6 mm). In addition
there shall be provided a feedbelt to carry the
material under and away from the knives, or a
slide feed set at an incline that will permit the
material to pass by gravity against the knives on
the intake side and away from the knives on the
discharge side.
9.12 Nougat Cutter (Class A). A hood shall cover at
least the top half of the knife or disc at all times
and be so constructed that the cutting operation
can be performed without danger to the
operator.
9.13 Meat, Fish and Other Food Grinders (Class
A):
a.
Every power driven food grinder of the worm
type shall be so constructed, installed or
guarded that eh employee’s finger cannot
come in contact with the worm.
2.
3.
A mechanical method of feeding the
worm which will prevent an
employee from contacting the worm
during the feeding operation.
A hinged interlocking grille or
grating over the hopper or pan
which will open the power circuit
when the grille or grating is lifted.
Such grilles or gratings shall be
designed and located as provided in
item 3 above.
5.
In large hand-fed grinders of the
type used in the wholesale or
manufacturing trades, where the
neck exceeds 62 mm diameter and
the opening is not guarded by grilles
or gratings, the distance from the
top of the neck to the worm shall be
not less than 915 mm and minimum
the
accessible distance from
working level to the worm shall not
be less than 2 235 mm.
b.
A pusher shall be provided for each grinder
and shall be used during the feeding
operation where it is possible to increase the
safety of the operation. Under no
circumstances shall a pusher be used in lieu
of the above methods of guarding.
c.
Before cleaning food grinders, the prime
mover shall be disconnected and the
controls locked in the ‘off” position.
Note: The engineer will accept the following
methods as being in compliance with this
code:
1.
4.
9.14 Meat Machines in an Abbatoire:
A permanently attached neck to the
cylinder enclosing the worm, the
circular opening of which shall be no
more than 63 mm in diameter at a
point at least 115 mm above the
worm.
bars
parallel
of
grating
A
permanently attached to the hopper
and spaced not more than 32 mm
apart providing the grating is not
less than 38 mm above the hopper
rim.
Other types of grilles or grating are
acceptable, provided the greatest
dimension in any opening does not
exceed 63 mm and is located no
less than 115 mm above the worm,
or more than 115 mm above the
hopper rim. Grilles or grating
attached to pans shall completely
a.
Swing cut-off-saw for cutting carcasses,
shall be provided with adequate guard to
protect the operator while the machine is in
use. The operator should be provided with
head and chest protective equipment.
b.
the scalding tank is filled
Scalding Tank
and some chemicals
water
with boiling
where carcasses of hogs are placed after
slashing the throat. In most cases, the
scalding tank has no overhead conveyor to
carry the carcasses from the tank to the
dehairing machine, instead this is done
manually by operator.
—
Recommendation: To prevent slipping
hazards, the catwalk surface should be
made of non skid materials.
46
CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
9.15 Meat Choppers (Class A). Knives or choppers
shall be enclosed.
9.16 Rolls (Class A). Rolls on all machines not
specifically mentioned which require the
presence of the operator to feed the machine
during operation shall be provided with a cover
or guard so arranged that the operator’s fingers
cannot be caught in the rolls.
9.17 Ice Cubing and Ice Scoring Machines (Class
A). Ice cubing and ice scoring machines shall be
enclosed on all sides to a height of not less than
1 830 mm, unless machine is also enclosed on
top with sheet metal or wire mesh guards having
no opening which exceeds 12.7 mm except for
the necessary openings to feed and discharge
the ice.
10.2 Extractors.
a.
No extractor shall be operated at a speed
greater than the manufacturer’s rating,
which shall be stamped on the basket where
easily visible, in letters not less than 6 mm in
height. The maximum permissible speed
shall be given in revolutions per minute.
b.
Each engine individual driving an extractor
shall be provided with an effective engine
stop and speed limit governor.
c.
The exterior of the basket including hoops or
bands shall be inspected at least every six
months to determine condition of basket.
The extractor shall be dismantled and the
bearings, bearing blocks, and basket shall
be inspected at least once a year and all
necessary repairs or replacement made. If
basket shows signs of weakness, it shall not
be used. A record of the inspection including
the date and name of person who made
inspection shall be kept on file in the plant.
Recommendation: All doors and removable
panels giving access to the saw should be
connected to limit switches which will not permit
the operation of the saws when the panels are
opened or removed.
9.18 Ice Breaker or Crusher (Class A). A hopper
shall be provided of such size and arrangement
that the hand of the operator cannot come in
contact with the revolving teeth or prongs while
the machine is in operation. If the top of the
hopper is less than 1 050 mm above the floor or
working level, a standard railing shall be
provided to prevent an employee from stepping
or falling into the hopper.
Exception: Automatic loading and unloading
extractors which are completely enclosed
with an enclosure of sufficient strength to
retain the basket in the event of rupture.
d.
10.3 Extractors (Screw Cover Type) (Class A):
9.19 Tobacco Stem Crusher (Class A). The rolls
shall be so enclosed that it will not be possible
for the operator’s fingers to come in contact with
them.
a.
A screw cover type extractors shall be
equipped with a metal cover at least 0.953
mm thick which shall entirely cover the
opening to the outer shell and shall be kept
in its closed position when the extractor is in
motion.
b.
The cover for the revolving container shall
be held securely in place by a lock nut on
the spindle or the container shall revolve in
the direction that will tend to tighten the
spindle nuts.
9.20 Cigar Cutter (Class A):
a.
b.
Each extractor shall be effectively secured
in position on the floor or foundation so as to
eliminate unsafe vibration.
The knives shall be provided with a metal
cover that will enclose the knives, or
A feed hopper which completely encloses
the knives shall be provided of such size
and so arranged that material be fed without
the operator’s fingers coming in contact with
the knives.
10.4 Extractors
(Automatically
Fed
and
Discharged) (Class A). The revolving bowl
shall b completely enclosed or guarded so as to
prevent contact with it during operation.
Section 10.0 Chemical Industry Machines
10.1 Gear or Chain Feeders. Gear or Chain Feeders
should be enclosed.
10.5 Extractors (Open Top, Bottom Discharge)
(Class A). Every extractor equipped with
removable plate vale in bottom of shell shall be
47
CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
with a safety trip device by which the
operator can disconnect the power and stop
the equipment in case of emergency.
provided with an interlocking device which will
prevent the introduction of the plow into the
• basket until the plate valve has been removed.
11.2 Stopping Limits for Calendars:
10.6 Rolls (Class A):
a.
Rolls on all machines, not specifically
mentioned, which require the continued
presence of the operator to feed with a
cover or guard, or
b.
A quick stopping or reversing device, so
arranged that the operator can actuate the
device while in his usual working position
should hands be caught.
a.
10.7 Soap Presses (Class A). Hand fed presses
shall be guarded, at point of operation, as
specified in Sections 4.3.1 and 4.3.4.
Exception: Where operating speeds above
61 rn/mm as measured on the surface of the
drive roll are used, stopping distance of
more than 2% may be permissible subject to
engineering determination.
Section 11.0 Rubber and Composition
Working Machines
11.1
Calender Rolls (Not Paper) (Class A):
a.
On each side of all calendars near both
ends of the face of the r’oll, there shall be a
vertical tight wire cable connecting with the
bar tripping mechanism. This shall be from
the top and fastened to the frame within 300
mm of the floor and at a distance of not less
than 25.4 mm from calender frame.
c.
At the “bite” of in-running open rolls where
sheeting, duck or other fabric is fed by hand,
a safety bar or cable connected to the
stopping device, shall be placed across the
full length of the face of the rolls. It shall be
so located that the operator’s fingers will trip
the stopping device before coming into
contact with the bite.
d.
b.
Safety devices shall be provided across the
front and back of all calendars extending the
full length of the face of the rolls and
designed to initiate instantly the process of
stopping the calender when either pushed or
pulled. The device shall not be more than 1
830 mm nor less than 1 675 mm above the
working floor or platform on which the
operator stands, and shall be within easy
reach of the operator when he is in normal
working position.
b.
Old Calenders. All calender drives in use of
contracted for prior to 1985 (the effective
year of issuance of this provision),
irrespective of the size of the rolls, shall be
made capable of stopping within a distance
of no more than 2 percent of the travel from
operating speed. The operating speed shall
be measured from the surface of the drive
roll and expressed in meters per minutes
(m/min). This rule shall apply to calendar
operating speeds up to 61 rn/mm while
running empty.
New Calenders. All new calender drives
purchased or contracted for after 1985 (the
effective year of issuance of this provision),
irrespective of the size of the rolls, shall be
stopped within a distance no more than 1.75
percent of the travel from operating speed.
The operating speed shall be measured
from the surface of the drive rolls and
expressed in meters per minute (m!min).
This rule shall apply to operating speeds up
76.25 rn/mm while running empty.
Exception: Where operating speeds above
76.25 rn/mm as measured on the surface of
the drive roll are used, stopping distances of
more than 1.75% may be permissible
subject to written justification by a
professional mechanical engineer. Stopping
distances shall be subject to engineering
determination.
11.3 Rubber Mills (Class A).
Calender equipment such as windups, idler
rolls and cooling drums shall be provided
48
a.
Mills shall be provided with a hopper of such
size and arrangement that it will protect the
operator’s hands against inadvertent contact
with the in-running nip point of the rolls
when feeding material, or
b.
Old Group Mills. For mills driven in groups
of two or more; in use, contracted for, or
constructed prior to 1985 (the effective year
CHAPTER 4— MACHINERY DANGER ZONE AND POINTS OF OPERATION
of issuance of this provision), irrespective of
the size of the rolls, shall be made capable
of stopping within a distance no greater than
2% of the travel of the rolls as measured on
their surface in meters per minute while
running empty.
c.
—
c.
11.9 Injection Molding Machine (Class A). Every
injection molding machine shall be guarded by
any one or more of the following methods:
a.
All guillotine bale cutters shall be equipped
with a two hand continuous control, or
b. A one-hand continuous control so located that
the operator cannot reach the control and the
point of operation at the same time.
By a sliding gate guard so designed and
installed that it interposes a barrier between
the dies and the operator before the dies
can close; and shall be so arranged that if
the gate can be opened during the closing
cycle, the cycle will be immediately stopped
or be reversed by the opening of the gate.
The sliding gate guard shall extend over the
top and to each side of the dies such a
distance so that it would be impossible for
the operator to come in contact with the dies
while these are closing. The danger zone on
the side of the machine opposite the
operator’s working position shall also be
guarded.
11.5 Bevel Cutters
Circular Knife
NonAutomatic (Class A). The circular knife shall be
covered with a metal hood which shall guard the
cutting edge down to point not more than 12.70
mm above the thickest portion of the material
being cut. A positive stop must be provided to
prevent the knife from passing the front edge of
the table.
—
b.
11.6 Cuttersheet Rubber (Horizontal Cutter Type)
(Class A). The exposed portion of the knife at
the sides of the sliding table shall be covered
with a metal enclosure so that the operator
cannot come into accidental contact with the
knife when feeding the machine. Any holes or
openings on this enclosure, whenever it may be
necessary to have them, shall not exceed 6mm
in any dimension.
By two-handed pressure devices or controls
which require the simultaneous use of both.
the operator’s hands during the entire die
closing cycle.
11.10 Thermosettlng Plastic Molding Presses
(Class A). Every thermosetting plastic molding
press shall be guarded by any one of the
methods covered in Section 4.3.1.
11.11 Tire Machine. The switch pedal which controls
the rotation of the frame while endless piles of
fabric are being adjusted by a bar held in the
operator’s hands must be so connected with the
brake that removal of pressure from the pedal
shall stop the machine.
11.7 Power Driven Rotary Saws and Slitters (Hand
Feed) (Class A). A metal hood shall cover the
cutting edge to a point not more than 12.70 mm
above the thickest portion of the stock.
11.12 Tube Splicer (Class A). Each tube splicer shall
be equipped with a two-hand control.
11.8 Tubing Machine (Class A):
a.
A bar or other device arranged to be
operated by knee, thigh, foot or hand
pressure, which will stop the machine.
Guillotine (Class A).
—
A bar or other device, connected with the
switch, so arranged that the operator’s
fingers cannot reach the worm without first
actuating the switch, or
New Group Mills. New mills driven in groups
of two or more; in use, contracted for, or
constructed after 1985 (the effective year of
issuance of this provision), irrespective of the
size of the rolls, shall be stopped within a
distance not greater than 1.75% of the travel
of the rolls as measured on their surface in
meters per minute while running empty.
11.4 Bale Cutters
a.
b.
11.13 Testing and Maintenance (Class A).
All hand-fed extrusion machines, including
tubing machines, shall be provided with
hoppers of such height and size of opening
as to make impossible for the operator’s
fingers to reach the worm, or
a.
49
The stopping device on each mill and on
each calendar shall be tested for operation
during each shift. When a group of rubber
mills is driven by one motor but stopped by
a safety device located at each mill, and
CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
the charging floor or platform, a standard railing
or enclosure shall be provided which will prevent
the operator from falling into the pan.
when a visible signal such as a lamp is
operated by the motor circuit opening switch
is open, and the safety device has been
tripped, then after mill line has been stopped
by actuating one safety trip for the first test
and before the mills are restarted, the
remaining safety devices may be tripped
and the lamp signals used as an indication
of the proper functioning of the tripping
devices and motor switch. After a particular
stopping device has been used to stop the
motor driving a group of mills for a test, the
same device may not be used for the same
purpose until all the other devices have
been similarly used.
b.
c.
Section 13.0 Cotton and Seed Cotton
Processing Machines
13.1 Saws:
Each stopping device shall be tested for
braking distance once a week by a
competent person, and a record of such test
shall be made and kept on file for at least
one year. Such records shall be available to
the division or its employees.
a.
All gin stands used in processing field cotton
or seed shall be provided with a positive
guard which shall be designed to prevent
contact with the gin saws while in motion.
The saw blades in the roll box shall be
considered guarded by location if they do
not extend the ginning ribs into the roll box
when breast is in the out position.
b.
Moving saws on lint cleaners having doors
giving access to the saws shall be guarded
by interlock barred barriers, or equivalent.
13.2 Gin Stand, Main Drive and Miscellaneous
Drives.
The employer shall cause all defects or
substandard condition revealed by the test
to be corrected.
a.
Such drives shall be completely enclosed or
guarded by means of standard railings or
equivalent protection provided. When
guarded by standard railing, where the
driver approaches the railing by less than
380 mm, shield guards shall be installed on
the railing extending at least 380 mm
beyond the impairment on either side.
b.
V-belt drives within standard railing
enclosures shall have the pulleys guarded.
The open end of the pulleys shall be no less
that 100 mm from the periphery of the
pulleys.
c.
Chains and sprockets within 2 130 mm of
the floor or working level shall be guarded.
Chains and sprockets more than 2 130mm
from the floor or working level need not be
guarded provided the bearings are packed
and accessible extension lubrication fittings
are used.
Section 12.0 Stone, Clay and Glass
Working Machines
12.1 Pug Mills (Class A). Pug mills shall be guarded
by:
a.
b.
c.
A substantial grating with openings no
greater than 100 mm, said grating to
completely cover the opening, or
A cover projecting 100 mm on all sides
which may be raised not more than 200 mm
above the machine or floor, so as to permit
loading into machine on all sides without
screening same through grating, or
A hoper completely encircling the opening
through which the machine is fed and
extending 400 mm or more above the blade.
In no case shall the top of the hopper be
less than 900 mm from any floor or working
level used by the pug mill operators or
attendants.
Platforms
13.3 Elevated
Enclosures.
and
Transmission
Where automatic conveyor feed is used,
said conveyor shall be completely enclosed.
a.
Elevated platforms shall be guarded as
provided in Section 2.3.9 of this Code.
12.2 Wet and Dry Pans, Mullers, Chasers and
Similar Mixing and Grinding Mills (Class A).
When the top of pan is less than 914 mm above
b.
Where belts, pulleys, chains, sprockets,
gears or shifting are within 380 mm
horizontally or less than 2 130 mm above
d.
50
CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
the plafform shield guards as provided in
Section 4.13.2 shall be used in addition to
standard railing guards.
below the floor level may be guarded by
standard railing guards having two boards of
midrail height or shall be covered by
substantial covers or gratings.
13.4 Power Drives
a.
Drives between gin stands shall be guarded.
Where individual pulley guards are used, the
guards must extend 100 mm beyond the
periphery of the pulleys.
b.
Drives which are accessible above the
shield guard shall be individually guarded.
13.5 Warning Device. A warning device which will
e.
All belt conveyors head pulleys, tail pulleys,
single tension pulleys and dip take-up
pulleys shall be so guarded that the entire
sides of the pulleys are covered. The guard
shall extend in the direction of travel of the
belt to such a distance that a person cannot
reach behind it and be caught in the nip
point between the belt and the pulley.
f.
Portable inclined conveyors shall have head
and tail pulleys or sprockets and other
power transmission equipment guarded
accordingly.
g.
Where necessary to pass over exposed
chain, belt, bucket, screw, or roller
conveyors, such crossovers shall be bridged
or catwalked properly equipped with
standard railings and toe boards and shall
have a safe means of access either fixed
ladder, ramp or stairway.
h.
Conveyors passing over areas that are
occupied or used by employees shall be so
guarded as to prevent the materials handled
from falling and causing injury to employees.
i.
Where workmen pass under
strands of chain conveyors
through or other effective means
strength to carry the weight of
chain shall be provided.
sound an audible signal before machinery is
started shall be installed in all gins. Such signal
shall be intense enough to be heard above the
general noise level.
13.6 Baler. An automatic interlock shall be installed
on all balers so that the upper gates cannot be
opened while the tramper is operating and the
tramper cannot operate while the gates are
open.
13.7 Burr Machines. Top panels of burr extractors
must be hinged and equipped with a sturdy
positive latch.
13.8 Conveyors
a.
All accessible screw conveyors shall be
guarded by substantial covers or gratings or
with an inverted horizontally slotted guard of
the trough type, which will prevent personnel
from coming into contact with the screw.
Such guards may consist of horizontal bars
spaced to allow material to be fed into the
conveyor and supported by arches which
shall be not more than 2 440 mm apart.
Screw conveyors under gin stands shall be
considered guarded by location.
b.
All accessible seed cotton conveyors shall
be of the belt type.
c.
Wherever practical in existing installations
screw conveyors shall be replaced with belt
conveyors.
d.
the return
a shallow
of sufficient
the broken
Section 14.0 Other Industrial Machinery in
Manufacturing Installations.
14.1 Machine Guards for Operator’s Protection.
Applicable machine guards of the types describe
shall be provided at points of operation and
danger zones to protect the operator from
hazards of accidental contact.
Screw conveyors 2 100 mm or less above
floor or other working level shall be
completely covered with substantial lids.
Screw conveyors which are 600 mm or less
above the floor or other working level; or
51
a.
Coupling Guards
pairs or groups of
guards which may mesh together to form
an enclosure around the point of operation
during machine operation.
b.
Chain Guards fixed-mounted or movable
hood guards covering the length of run of
power of chains.
—
—
-
CHAPTER 4- MACHINERY DANGER ZONE AND POINTS OF OPERATION
c.
fixed-mounted or movable
Belt Guards
guards or enclosures covering the length of
run of belts.
d.
Distance Rail Guards fixed-mounted or
movable guards designed to prevent
personnel from moving into danger zones.
15.2 Outdoor installations shall be
enclosure for weather protection.
—
e.
fixed-mounted or
Hood Guards
retractable enclosures covering the vicinity
of the point of operation or danger zone.
f.
Water Splash Guards fixed-mounted or
retractable water resistant enclosures
covering the vicinity of the point of the
operation or danger zone and designed to
contain or direct liquid splashes and spills.
g.
15.1 Electrical Safety Hazards shall be painted in
red-orange color.
—
terminal
15.3 Motor
weatherproof.
box
covers
drip
shall
proof
be
—
15.4 In wet workplaces, water splash motor enclosure
shall be provided.
15.5 In dusty environment, dust hoods shall be
placed on top of motor but allowing free
circulation of cooling air.
—
15.6 Electrical cable conduit pull boxes shall be
weatherproof, liquid-tight, air-light enclosures
when installed outdoors.
fixed-mounted
Explosion Guards
explosion resistant enclosures covering the
vicinity f the point of operation or danger
zone and designed to contain flying
materials.
—
h.
retractable type
Fire Explosion Doors
explosion resistant enclosures covering
vicinity of the point of operation of danger
zone and designed to contain energy
bursts and flying materials.
i.
Railings and Screen Doors Retractable
type railings or access doors resistant to
flying materials and encloses the vicinity of
the point of operation or danger zone, and
is designed to isolate the same without
impairing ocular inspection.
Section 16.0 Personal Protection in
Workplaces
16.1 Personal Protective Equipment. Personnel
Protective Equipment (PPE) shall be considered
the last line of defense against hazards in the
work environment. The engineer shall specify
and require the use of PPE to protect personnel
from known or possible hazards in the
workplace.
—
—
16.2 Employers’ shall protect their employees by
providing appropriate and approved protective
tools, devices, equipment and appliances such
as, but not limited to the following:
a.
b.
c.
d.
e.
f.
g.
h.
i.
14.2 Machine guards provided for mechanical power
transmission from the prime mover to the point
of operation shall be made of enclosure that
permits visual inspection at a distance while
machine is running.
14.3 For easy identification of safety
machine guards shall be painted in
and restricted floor area shall be
yellow strip line in walk aisles
machinery.
hazards, all
yellow color,
painted with
around the
j.
k.
Head Guards
Face Shields
Eye Goggles
Ear Muffs
Nose Aspirator
Hand Gloves
Arm Sleeves Shield
Body Apron Shield
Leg Sleeve Shield
Foot Safety Shoes
Foot Rubber Boots
163 Radiation hazards in workplaces shall be
identified and appropriate warning signs shall be
posted.
14.4 For automatic start-stop machines, a warning
sign, tag or nameplate shall be displayed in
strategic location in the workspace.
16.4 Eye hazard from welding arc electrical flashes in
welding shop shall be shielded by wood panel
barrier as protection for observers and other
personnel in the work area.
Section 15.0 Protection for Electrical
Machinery in Commercial & Industrial
Installations
52
CHAPTER 5- CRANES AND OTHER HOISTING EQUIPMENT
Chapter 5
CRANES AND OTHER HOISTING EQUIPMENT
Section 1.0 Scope
Bumper. A device which stops the moving part at the
limit of travel of a trolley, bridges, or crane operating
on rails, and prevents further motion beyond that point.
The provisions in this Chapter apply to overhead
traveling or bridge cranes, storage bridges, gantry
cranes, portal cranes, jib cranes, hammerhead cranes,
pintle cranes, wall cranes, tower cranes, and any
modification of these types which retain their
characteristic features of the above mentioned cranes
except when a provision specifies a particular type of
crane. It also includes safety regulations for mobile
type cranes and hoists.
Cab. An enclosure for housing the operator and the
hoisting mechanism, power plant, and equipment
controlling crane.
.
Cage. An enclosure for housing the operator and
equipment controlling a crane.
Crane. A machine for lifting or lowering a load and
moving it horizontally, in which the hoisting
mechanism is an integral part of the machine. It may
be driven manually or by power and may be a fixed or
mobile machine, but does not include stackers, or lift
trucks.
Section 20 Definitions
Boom. A timber or metal section or strut which is
pivoted or hinged at the heel (lower end) at a fixed
point on a frame, mast, or vertical member. Its head
(upper end) is supported by chains, ropes or rods to
the upper end of the frame, mast or vertical member.
A rope for raising and lowering the payload is run
through a sheave or block at the head of the boom.
The length of the boom shall be taken as the straightline distance between the axis of the foot pin and the
axis of the end sheave pin.
Some of the common types of cranes are defined as
follows:
1.
Boom Type Mobile Crane. A self-propelled crane
equipped with a boom and mounted on a chassis
which is supported on either rubber tires, endless
belts or treads, or railway wheels running on
railroad tracks.
2.
Cantilever Gantry Crane. A crane in which the
bridge girders or trusses are extended
transversely beyond the crane runway on one or
both sides. Its runway may be either on the
ground or elevated.
Booming, Luffing or Topping. Raising or lowering
the head of a boom.
3.
Crawler Crane. A boom type mobile crane
mounted on endless tracks or tread belts.
Brake (Electric). An electric motor acting as a brake
by regenerative, counter-torque, or dynamic means.
4.
Gantry Crane. A crane similar to an overhead
traveling, except that the bridge for carrying the
trolley or trolleys is rigidly supported on two or
more movable legs running on fixed rails or other
runway.
5.
Hammerhead Crane. A rotating counterbalanced
cantilever equipped with one or more trolleys and
supported by a pivot or turntable on a traveling or
fixed tower.
6.
Jib Crane. A fixed crane consisting of a supported
vertical member from which extends horizontal
Boom Type Excavator. A power operated excavating
crane-type machine used for digging or moving
materials. Some excavators of this type are commonly
known as dipper stick shovels, back diggers, trench
hoe shovels, draglines, grab buckets, clamshell or
orange peel, excavators.
Brake (Electrically Operated). A friction
actuated or controlled by electrical means.
brake
Bridge (of an Overhead, Gantry, or Storage Bridge
Crane). Structural member or members supporting
one or more trolleys.
Buffer. A cushioning device at the end of a trolley,
bridge, or other moving part of a crane operating on
rails to minimize shock in the event of collision.
53
CHAPTER 5— CRANES AND OTHER HOISTING EQUIPMENT
structure, adapted to hoist and swing load over
high obstructions and mounted upon a fixed or
mobile tower-like gantry. The revolving crane may
be supported on the lower tower by a revolving
mast or by a turntable.
swinging arms carrying a trolley hoist or other
hoisting mechanism.
7.
Locomotive Crane. A boom type mobile crane
consisting of a self-propelled car operating on a
railroad track, upon which is mounted a rotating
body supporting the power operated mechanism
together with a boom capable of being raised or
lowered at its head (outer end) from which is led to
the wire rope or chain connected to the hoisting
mechanism for raising or lowering a load.
8.
Motor-Tractor Crane. (see crawler crane).
9.
Motor Truck Crane. A boom type mobile crane
mounted on a motor truck frame or rubber-tire
chassis.
18. Tractor Crane. (caterpillar
crane).
crane) (see crawler
19. Wall Crane. A crane having jib with or without a
trolley and supported from a side wall or line of
columns of a building so as to swing through an
arc.
the structure upon which a crane
Crane Runway
runs, and may be:
—
10. Overhead Travelling or Bridge Crane. A crane
on a pair of parallel elevated runways, adapted to
lift and lower a load and carry it horizontally
parallel to, or at right angles to, the runways, or
both; and consisting of one or more trolleys
operating on the bridge, which in turn consist of
one or more girders or trusses mounted on trucks
operating on the elevated runways with its
operation limited to the area between the runways.
11. Pillar Crane. A fixed crane consisting of a vertical
member held at the base, with horizontal revolving
arm carrying a trolley.
1.
A structure consisting of columns, longitudinal
bracing and elevated beams, girders, or trusses,
to support traveling or bridge cranes.
2.
Elevated beams, girders, or trusses in a building
or on the side of a building, for supporting traveling
cranes.
3.
Surface tracks or rails.
4.
Tracks or rails on walls or trestles.
Derrick. A structure or building appurtenance for
hoisting, but does not include a hoistway nor a car or
platform traveling thorough guides.
12. Pillar Jib Crane. A fixed crane consisting of a
vertical member held at the base, with horizontal
revolving arm carrying a trolley.
Hoist. A mechanical contrivance for raising or
lowering a load by the application of a vertical pulling
force, but does not include a car or platform traveling
through guides.
13. Pintle Crane. A crane similar to the hammerhead,
but without a trolley, and which supports the load
at the outer end of the cantilever arm.
Some of the common types of hoist are defined as
follows:
14. Portal Crane. A gantry crane without trolley
motion, which has the boom attached to a
revolving crane mounted on a gantry, with the
boom capable of being raised or lowered at its
head (outer end).
15. Semi-Gantry or Single Leg Crane. A gantry with
one of the bridge rigidly supported on one or more
movable legs, running on a fixed rail or runway,
the other end of the bridge being supported by a
truck running on an elevated rail or runway.
16. Semi-Portal Crane. A portal crane mounted on a
semi-gantry frame instead of a gantry frame.
17. Tower Crane. A portal crane, with or without an
opening between the legs of its supporting
54
1.
Base-Mounted Electric Hoist. A hoist similar to
an overhead electric hoist, except that it has a
base or feet and may be mounted overhead, on a
vertical plane, or in any position for which it is
designed.
2.
Clevis Suspension Hoist. A hoist whose upper
suspension member is a clevis or a U-shaped
structural member designed to carry pulling loads.
3.
Hook Suspension Hoist. A hoist whose upper
suspension member is a hook.
4.
Monorail Hoist. A trolley suspension hoist whose
trolley is suspended from a single rail.
CHAPTER 5- CRANES AND OTHER HOISTING EQUIPMENT
5.
6.
Overhead Electrical Hoist. A motor-driven hoist
having one or more drums or sheaves for rope or
chain, and supported overhead. It may be fixed or
traveling
Section 3.0 General Requirements For
Cranes
3.1
Simple Drum Hoist. A hoist with one or more
drums controlled by manually operated clutches,
brakes or ratchet and pawl on drum and control
levers, which is operated by hand or power.
Access to Cage, Cab or Machine House
Required:
a.
Access to the cage, or machine house shall
be afforded by a conveniently placed
stationary ladder, stairs, or platform
requiring a step-over. No gap exceeding 300
mm (and in no case exceed 815 mm) shall
be so located that a person approaching or
leaving the crane shall not be exposed to
dangerous shear hazards.
b.
For the bridge and gantry cranes, there shall
be a ladder, stairs or other safe means
provided for convenient access to the bridge
walkway. Where the cage is attached to and
below bridge girders, no portion of the cage
or cage platform shall be in the protected
area between the girders unless there are
adequate bridge stops or bumpers to
prevent the trolley from passing over said
projected area opposite the cage.
c.
When necessary to go out on booms or
bridges to oil the blocks or other parts of the
machinery, each boom or bridge shall be
equipped with a suitable oiler’s walkway or
platform with grab irons giving access to the
outrig blocks and machinery. Permanent
elevated platforms attached to the building
at the end of the bridge crane runways and
at the same level of the bridge will be
acceptable in lieu of the oiler’s platform on
the bridge. Single girder or monorail bridges
with underhung trolleys and hoists are
exempt from this requirement provided the
hoists and trolleys are serviced or repaired
from a safe portable ladder or other safe
temporary means. Booms which can be
and are safely lowered to a safe location for
such servicing operation will be exempt from
this requirement.
d.
Where practicable every overhead traveling
crane walkway shall have a headroom of at
least 1 950 mm. However, when such
headroom is not practicable, the crane
walkway shall have at least 1 500 mm
clearance or it shall be omitted from a crane
and a permanent elevated platform attached
to the building at the end of the crane
runway be provided.
Note: This type of hoist is known to the trade as a
contractor’s hoist and is usually a portable unit
7.
Double Drum Hoist. A simple drum hoist having
two independent hoisting drums.
8.
Single Drum Hoist. A simple drum hoist having
only one hoisting drum.
9.
Single Fixed Drum Hoist. A single drum hoist
with the drum geared or fixed directly to the power
unit (including the speed reducing apparatus)
instead of by means of friction clutches.
10. Triple Drum Hoist. A simple drum hoist having
three independent hoisting drums.
11. Trolley Suspension Hoist. A hoist whose upper
suspension member is a trolley, for the purpose of
running the hoist below a suitable runway, it may
be either floor or cage-operated.
Jib: (1) A horizontal arm, for supporting a trolley or fall
block, which does not change its inclination with the
horizontal; or (2) An extension added to the head of a
boom for increasing the reach.
Radius (of a Crane or Derrick). The horizontal
distance from the center of rotation of a tower,
hammerhead portal or pillar crane, or derrick to the
center of the hook or load.
Swinging or Slewing. The act of moving a boom
through a horizontal arc.
Trolley. A truck or carriage on which the hoisting
mechanism is mounted and which travels on an
overhead beam, or track. It may be either “over
running” (riding above its wheels); or “under-running”
or suspended under the beam, bridge, or track.
Truck (of an Overhead, Gantry, or Locomotive
Crane). The framework and wheels operating on the
runway or rails and supporting the bridge, trolley, or
body of the crane.
55
CHAPTER 5- CRANES AND OTHER HOISTING EQUIPMENT
3.2
3.3
b.
A gong or other effective warning signal
shall be mounted on each cage or cab
controlled crane equipped with a power
mechanism. Cage or cab
traveling
controlled cranes operating over areas
congested with employees may be required
to be equipped with automatic warning
devices which can be sounded continuously
while the crane is in motion.
Any cage or cab controlled crane whose
warning device has become inoperative
shall not be operated until the warning
device is repaired or replaced. Temporary
crane operation will be permitted provided
there is an available flagman whose sole
duty is to warn those in the path of the crane
or its load.
Fire Extinguisher. A carbon-tetrachloride,
carbon dioxide, or other non-conducting
medium, portable fire extinguisher shall be kept
in the cage, cab or machine house of each
electric or internal combustion engine crane.
Note: Careshould be taken when using carbon
tetrachioride in an enclosed space and such
space should not be re-occupied until thoroughly
ventilated.
3.5
d.
All electrically operated cranes shall have
their controller plainly marked to indicate its
functions and which equipment it controls.
e.
The controller operating handles shall be
located within convenient reach of the
operator.
f.
As far as is practicable, the movement of
each controller handle shall be in the same
resultant
the
as
direction
general
movements of the load.
g.
The controls for the bridge and trolley shall
be so located that the operator can readily
see the direction of travel while operating
the controls.
h.
All electric cranes of the same type
operating in a given plant shall e so wired
that like motion of controller handles will
produce like effect in similar controlled
mechanisms.
Warning Devices:
a.
3.4
voluntary effort to move it from the “off’
position to the “on’ position.
Outdoor Cages, Cabs, or Machine Houses.
The cages, cabs, or machine houses on cranes
used in inclement weather shall be enclosed to
protect the operator.
Controllers:
a.
Each electric cage-operated crane shall be
provided with a device which will disconnect
all motors from the line in case of power
failure or interruption. This device or
disconnecting means shall not permit any
motor to be restarted until the controller
handle is brought to the ‘off” position, or a
reset switch or button is operated.
b.
For floor-operated cranes, the controller or
shall
rope-operated
it
controllers,
automatically return to the ‘off’ position
when released by the operator.
c.
Lever operated controllers shall be provided
with a mechanical device which will hold the
handle in the “off” position requiring
56
3.6
Hoist Limit Switches. The hoisting motion of all
electric overhead traveling cranes shall be
provided with a suitable and effective enclosed
type limit switch so placed and arranged as to
disconnect the hoist motor and apply the brake
in time to stop the motor before the hook passes
the highest point of safe travel.
3.7
Brakes:
a.
Each electric crane hoist motor shall be
provided with an electrically or mechanically
operated brake so arranged that the brake
will be applied when the power is cut off
from the hoist. This brake shall have
sufficient holding torque to sustain not less
than one and one-half times the rated load.
b.
Each independent hoisting unit shall be
equipped with two braking means except for
worm-geared hoist where the angle of the
worm is such as to prevent the load from
lowering. One brake shall be covered by
above, and each braking means shall be
capable of sustaining or safely controlling
the lowering of not less than one and one
half (1 1,4) times the rated load.
c.
Each ingot-pouring crane shall be provided
with two (2) brakes each of which shall have
CHAPTER 5- CRANES AND OTHER HOISTING EQUIPMENT
sufficient torque to sustain one and one-half
(1 1/2) times the rated load.
3.8
3.9
rated load at maximum radius can be held
suspended without the help of the boom
hoist brake and with crane mechanism
stationary.
Foot Brake Pedal. Foot brake pedals shall be
so roughened or covered with high friction
material that the operator’s foot will not easily
slip off.
3.12 Runway Bumpers. At the limits of travel of the
bridge or gantry structures, bumpers shall be
provided which will prevent bridge or gantry
structures from leaving the ends of the rails. If
the bumpers engage the tread of the wheel they
shall be of a height at least equal to the radius of
the wheel.
Locking Device. A locking device capable of
withstanding 50 percent more than the
maximum rated load shall be provided on each
hand or foot operated hoisting motion brake
unless a paw is provided on the drum.
3.13 Trolley Bumpers:
3.10 Brakes for Bridge and Swinging Motion:
a.
b.
c.
3.11
On cage-operated cranes with the cage
mounted directly on the bridge grinders, a
foot brake to properly retard and stop the
motion of the bridge shall be installed unless
the bridge stops automatically when the
power is cut off. This does not apply to
underslung cab monorail cranes.
Brakes for retarding the motion of the bridge
shall be capable of retarding it at the rate of
305 mm/mm., while full load is being carried.
b.
Ratchet and Pawl. A ratchet and pawl, shall
be provided on the mechanism for raising
and lowering the boom, unless a self-locking
worm and gear is part of the mechanism.
There shall be no intervening clutch
between any boom hoist drum and its
reduction gear train.
b.
If there is more than one trolley on the same
bridge girders, buffers or other cushioning
shall be placed between the trolleys.
3.15 Truck Fenders:
Booming Mechanism. All boom-type cranes
equipped with a mechanism for raising and
lowering the boom shall comply with the
following requirements:
Brake.
geared
boom
Worm
hoist
mechanism the worm angle of which is such
as to permit the loaded boom to lower shall
be equipped with a brake to hold the loaded
boom in any position.
Bumpers shall be provided at each end of
the trolley travel to prevent trolleys leaving
the rails. If the bumpers engage the tread of
the wheel they shall be of a height at least
equal to the radius of the wheel.
3.14 Bridge or Gantry Buffers. If there is more than
one crane on the same runway, buffers or other
cushioning devices shall be placed between the
crane at both ends of the bridge or gantry.
The swinging or slowing mechanism on
boom-type cranes shall be provided with a
brake or lock having adequate holding
power in either direction.
The lever
operating this brake or lock shall have a
device by which it can be secured in the
hold or locked position.
a.
a.
a.
Bridge
cranes
extend
in front
truck wheels, except on under hung
shall be equipped with fenders which
below the top of the rail and project
of the truck wheels.
b.
Gantry, tower, hammerhead, or portal crane
truck wheels shall be equipped with wheel
guards, or be otherwise similarly guarded at
both ends of each truck to prevent a person
being crushed beneath the wheels. The
clearance between the guard and the rail
shall be such as will afford maximum
protection
against
crushing
injuries.
Wherever practicable 12.70 mm clearance
shall be maintained.
3.16 Capacity Marking and Load Indication:
a.
Note: A worm and gear shall be accepted
as self-locking under this code when full
57
The maximum rated load of all cranes shall
be plainly marked on each side of the crane,
and if the crane has more than one hoisting
unit, each hoist shall have marked on it or its
load block its rated capacity; and this should
be clearly legible from the ground or floor.
CHAPTER 5— CRANES AND OTHER HOISTING EQUIPMENT
b.
c.
Section 4.0 Boom Type Mobile Cranes
Each variable radius boom-type crane shall
be equipped with a safe load diagram or
table which will give a clear indication of the
permissible loads at the various radii.
4.1
Operating Levers:
a.
Lever operated controllers shall be provided
with a mechanical device which will hold the
handle in the “off” position requiring
voluntary effort to remove it from “off’ to the
“on” position.
b.
The operating levers shall be located within
convenient reach of the operator.
If change-speed gear is used on the lifting
motion, the rated load for each speed shall
be similarly indicated.
3.17 Runway Repair. No repairs on traveling crane
runways or within such proximity to same as to
constitute a hazard to workmen shall be made
unless a wheel stop of a height at least equal to
the radius of the wheel is secured to each rail
and a warning sign is placed on each rail a
reasonable distance from the worker, or properly
shielded rail-road torpedoes or watchman are
used to warn workers of the approach of the
crane.
4.2
Boom Stops. Booms shall have a device
designed and constructed to prevent the boom
from falling over backwards.
4.3
Capacity Marking. Substantial plates of metal
or other durable material shall be attached at a
conspicuous place on the crane have cast or
stamped thereon the rated load at the maximum
and minimum radii. Suitable signs shall also
provide the rated load for at least two other
points on the boom, and which shall be visible
on the boom along both parallel and transverse
tot the line of travel. The indicators shall be
given for loads both with and without outriggers
when such outriggers are provided.
4.4
Access to Cage, Cab, Machine and Boom
Blocks:
3.18 Crane Runways:
a.
Runway columns shall
anchored to foundation.
b.
The structure shall be free from excessive
vibration under operating conditions.
c.
Runway girders shall be level and parallel
within commonly accepted engineering
tolerances.
be
securely
3.19 Rails:
a.
Rails shall be securely attached to the
girders or to the foundation.
b.
Rails shall be level, in elevation with each
other, parallel and in correct span within
commonly accepted engineering tolerances.
3.20 Clearances. All traveling cranes the supporting
trucks or wheels of which travel rails on the
ground shall have at least 600 mm clearances
between the crane and stationary structures or
stacks or piles of materials. Where impossible to
obtain said clearance in existing installation
such impaired passageway areas shall be well
marked or placarded or when practicable shall
be guarded by standard railings or barricades to
prevent traffic.
58
a.
Boom type mobile cranes and boom type
excavators shall be provided with steps and
handholds or other safe means so located
as to give convenient and safe access to the
cage, cab, or machine house.
b.
When necessary to go out on booms to oil
the blocks or other parts of machinery, each
boom shall be equipped with substantial
oiler’s walkway or platform and grab-irons
giving access to the outrig blocks and
machinery. Booms which can be safely
lowered thereto for necessary service are
exempted from this code.
4.5
Protection for Operators of Outdoor Cranes.
The cages, cabs, or machine house on outdoor
cranes shall be enclosed to protect the operator
from the inclement weather except when such
enclosure would interfere with the safe operation
of the crane.
4.6
Gage Glasses. Gage glasses shall be of the
reflex type or shall be guarded by means of wire
CHAPTER 5- CRANES AND OTHER HOISTING EQUIPMENT
mesh or similar guard to prevent injury from
flying pieces of glass.
4.7
Couplers:
a.
b.
4.8
4.9
separate drums permanently keyed to the
same shaft.
4.12 Warning Device. An adequate whistle, gong,
bell or other warning device shall be provided for
all boom type mobile cranes.
If locomotive cranes are equipped with
couplers these must be extended to clear
the revolving tank end of the crane.
4.13 Wheel Guards. Locomotive cranes shall be
provided with either a running board which shall
extend full width of the truck bed. And with a
grab iron extending across and near outer end
of the truck bed, or with a pilot or fender which
will prevent a man being crushed beneath the
truck wheels.
Automatic couplers shall be provided on
cranes that switch or couple to cars so
equipped.
Lubricator Glass. The steam lubricator glasses
on all locomotive cranes and steam shovels
shall be effectively guarded to prevent injury to
flying glass unless the lubricator is of the bull’s
eye type or sight feed glass.
4.14 Truck Wedges or Jacks. Where loads greater
than the capacity of the springs are to be lifted,
locomotive cranes shall be provided with
suitable removable wedges or jacks for
transmitting loads from the crane body directly
to the wheels without permitting the truck
springs to function, when handling heavy loads.
These wedges should be removed, or jacks
released in a positive manner, for traveling.
Brake or Locking Device. Boom type mobile
cranes shall be equipped with an effective brake
or swing lock for the swinging mechanism. The
braking mechanism shall be equipped with a
device to secure it in holding position.
4.10 Booming Mechanism:
a.
Every worm guarded booming mechanism
whose worm angle is such as to permit the
loaded boom to lower shall be equipped with
a brake to hold the loaded boom in any
position.
b.
A ratchet and pawl shall be provided on the
mechanism for raising and lowering the
boom, unless a self-locking worm and gear
is part of the mechanism or unless the
booming mechanism is of such design as to
prevent the free fall of the bottom upon
release of the boom hoist brake.
4.15 Fire Extinguisher. A carbon tetra-chloride,
carbon dioxide, ansul, or other non-conductive
medium hand fire extinguisher shall be kept in or
just outside the cage cab or machine house of
each electric, internal combustion engine or
steam driven mobile boom type crane.
4.16 Lighting. Boom type mobile cranes which
operate at night shall have loads hooks and
working areas adequately illuminated. Such
lighting can be accomplished either by outside
lighting placed on the booms or cabs. Boom
heads and hooks should be painted with high
visibly yellow or other contrasting colors.
Section 5.0 Hoists
Note: A worm and gear will be accepted as
self-locking under this code when full rated
load at maximum radius can be held
suspended without the help of the boom
hoist brake and with crane mechanism
stationary.
5.1
Limit Switches. Each overhead electric hoist
motor shall be equipped with an effective
enclosed type limit switch so placed and
arranged as to disconnect the motor and apply
the brake in time to stop the motor before the
hook passes the highest point of safe travel.
5.2
Brakes:
4.11 Rigging of the Boom Hoisting Line:
a.
b.
No line shall be wound on any free running
drum of a boom type mobile crane.
a.
All boom type mobile cranes shall have one
end of the boom line dead ended except
where ends of the boom line are on
59
Each electric hoist motor shall be provided
with an electrically or mechanically operated
brake so arranged that the brake will be
applied when the power is cut off from the
hoists. This brake shall have sufficient
CHAPTER 5- CRANES AND OTHER HOISTING EQUIPMENT
positioned for trolley travel from stationary
rails to movable bridges or vice-versa.
holding torque to sustain not less than one
and one-half times the rated load.
b.
Each independent hoisting unit shall be
equipped with two braking means except
worm geared hoists, the angle of whose
worm is such as to prevent the load from
lowering and simple drum hoists which need
have but one braking means. One brake will
be so covered by:
1.
2.
5.6
Control Equipment. Operating controls shall
be plainly marked to indicate the direction of
travel.
5.7
Warning Device. Each cage controlled hoist
shall be equipped with an effective warning
device.
Section 6.0 Derricks in Permanent
Location
Above and each braking means
shall be capable of sustaining or
safely controlling and lowering not
less than one and one-half (1 %)
times the rated load.
6.1
Construction:
a.
The hoisting drum of all hand power
hoists shall be equipped with an
effective brake, and shall be
provided with a ratchet and pawl of
sufficient strength to hold the load in
any position.
Derricks of appropriate design, proper
strength and size for the work to be
performed shall be constructed of steel or
suitable alloy or of sound, seasoned number
of adequate cross-section considering its
use, unit strength, resistance to or protection
against deterioration and shall be anchored
so as to prevent tripping or collapsing.
5.3
Hoist Trolley Frames. Trolley frames shall be
so constructed so as to avoid dangerous
spreading under load. Trolley frames, which
shows signs of excessive spreading under load
shall not be used until repaired or replaced.
5.4
Capacity Marking. Each hoist designed to lift
its load vertically shall have its rated load legibly
marked on the hoist or load block or some
equally visible space.
b.
Guyed derricks should have at least six
guys (only under special consideration of
circumstances shall guyed derricks be
allowed to have less than four guys).
5.5
Stops:
c.
Guys shall be of adequate strength and
where exposed to the weather shall be
adequately
otherwise
or
galvanized
ring.
t
weathe
agains
ed
protect
d.
If boom is longer than the mast, means shall
be provided to prevent the top gooseneck,
spider, gudgeon, pin or guy plate from being
pulled off when the boom is in high position.
e.
Reinforcing steel shall not be used for guy
line anchors unless its specifications for
tensile strength, elastic limit, ductility,
bending properties, and finish are at least
equivalent to those required in ASTM
“Standards Specifications for Structural
Steel or Bridges and Buildings” (A7-42).
a.
b.
c.
Braces and fittings of suitable metal,
adequate strength and appropriate design
shall be used and maintained in proper
adjustment while the derrick is in operation.
Stops shall be provided at the end of
monorails and crane runways and may
contact either the frame of the wheels.
Stops designed to contact the wheels shall
be of a height not less than the radius of the
wheel.
A stop, which shall operate automatically,
shall be provided at each switch, dead end
rail or turn table to prevent the trolley from
running off when the switch is open.
Every overhead monorail system of tracks,
which employs the use of traveling transfer
bridges between tracks, which employ the
use of traveling transfer bridges between
stationary rails, shall be equipped with
automatic locking devices which will
positively lock the traveling bridges rail to
the stationary rails when the bridges is
6.2
60
Load Indication:
CHAPTER 5- CRANES AND OTHER HOISTING EQUIPMENT
a.
Every derrick shall have plainly marked on it
the length of the boom, the rated load and
the corresponding radius.
b.
Eye splices shall be made in a manner to
develop maximum splice efficiencies as set
forth in the manufacturer’s tables.
b.
Derricks of variable radius shall have
substantial plated metal or other durable
material conspicuously posted on which
shall be given the rated load of at least four
different radii of operation, including the
maximum and minimum radius.
c.
Where wire rope clip attachments are used
they shall be made with U-bolts on the dead
or short end of the rope and saddle on the
live end.
d.
No ‘Contractor’s Standby” (knot and clip)
attachment shall be used as an end
connection on any permanent hoisting sling
or rope.
e.
The maximum number of clips for end
attachment shall be not less than those
indicated in the manufacturer’s table, but in
no case shall it be less than three for any
permanent installation. The clips shall be
spaced at a distance equal to at least six
times the diameter of the rope.
Section 7.0 Auxiliary Hoisting Equipment
f.
All clip or clamp bolts shall be kept tight.
7.1
g.
Where swaged or compressed fittings are
used they shall be applied in a manner
specified by the manufacturer.
6.3
Hoisting Ropes. Wire ropes running from
hoisting machine to derrick shall be guarded if
within 2 135 mm of floor or platform.
6.4
Access to Sheaves, Bearings and Blocks. If
necessary to go out on derrick booms to service
sheaves, bearing or blocks, said boom must be
equipped with substantial oiler’s catwalk and
necessary grab irons to give access to the
equipment to be serviced.
Hoisting Chains and Ropes:
a.
b.
All chains, wire ropes, and fiber ropes used
for hoisting purposes shall be of sufficient
strength to safely lift or otherwise handle the
loads. The maximum allowable working
loads shall be based on manufacturer’s
tables.
7.4
Every hoist chain, wire rope and fiber rope
in hoisting drums shall be of sufficient length
that the hoist hook shall at least reach the
floor, ground, or lowest working level.
Where this is not practicable lower-limit
switches may be used to restrict the
downward limit of travel.
Exemption: Chain hoists employing pocket
sheaves instead of drums.
7.2
Hooks, Slings and Fittings. All hooks, slings
and other fittings shall be of correct size for the
work to be done and shall have strength
sufficient to safely sustain the loads imposed
upon them.
7.3
End Attachment:
a.
Where socketing is done it shall be done
with zinc (spelter) or in a manner specified
by the manufacturer of the wire rope.
61
Chain Splices:
a.
No hoist chain shall be spliced by any
makeshift means.
b.
Knots shall not be tied in the chain to
shorten it.
c.
Lap link, cold shuts or patent repair links
shall not be used for hoist chain or slings
unless such device will develop greater
strength than the chain.
7.5
Hoist of Sling Hooks, Rings, and Chain
Links, Defective. The use of deformed or
defective hooks, rings, or chain links shall be
discontinued forthwith. Deformed hooks or rings
shall be reshaped only by the manufacturer of
the hooks or rings under proper metallurgical
control and proof tests unless the employer is
equivalently competent to make these repairs
and tests.
7.6
Sheave Nip-Points. All nip or contact points
between ropes and sheaves which are
permanently located within 2 135 mm from the
floor or working platform shall be guarded.
CHAPTER 5- CRANES AND OTHER HOISTING EQUIPMENT
Section 8.0 Operating Rules
8.1
Size of Load. A crane, derrick, or hoist shall not
be loaded beyond the rated capacity or safe
working load whichever is smaller.
8.2
Attaching the Load:
8.3
8.4
a.
The load shall be attached to the hook by
means of slings or other suitable and
effective means which shall be properly
rigged to insure the safe handling of the
load.
b.
Chain and wire rope slings shall be freed of
kinks or twists before use.
c.
Baskets, tubs, skips, or similar containers
used for hoisting bulk materials shall be
loaded so as not to exceed their safe
carrying capacity.
Holding the Load:
b.
8.5
When a load of any kind is to be suspended
for any considerable time, the dog or pawl,
of one is provided shall be used in addition
to the brake which shall also be applied.
Cranes, hoists, or derricks shall not be left
unattended while load is suspended over
water, is barricaded or is blocked up or
otherwise supported from below during
repairs of emergency.
Limit Switch:
a.
b.
Signalling. Only qualified employees shall give
signals. No one would give signal except
employees who are specifically designated and
authorized to do so by the employer. Crane
operators shall not accept signals except from
those specifically designated and authorized to
give same.
8.7
is
It
Required.
Signals
of
Posting
recommended that the following Standard
Signals be adopted and used in connection with
all hoisting operations. Other signal codes or
system may be used however if they provide
quick and precise transmission of instructions to
the operator. Regardless of the signal system
employed, there shall be conspicuously posted
in the vicinity of the hoisting operation legible
chart depicting and explaining the system of
signals used.
a.
Riding on Loads. No employee shall be
required to or shall ride on loads, slings, hooks,
buckets or skip boxes except under condition or
exceptions covered by other rules of the
division.
a.
8.6
Before an electric crane is operated for the
first time during any shift, the operator shall
test the operation of the limit switch over a
cleared area under no load and shall report
any defect to his employer who shall have
the defect corrected before the crane is
permitted to operate.
The limit switch shall never be used as an
operation control unless designed for such
use. Where such limit switches are used as
operating controls there shall be a second
limit switch located behind the control limit
switch.
62
One.hand Signals:
1.
vertical,
forearm
With
Hoist.
in small
hand
forefinger point, move
circle.
horizontal
2.
Lower. Arm extended, palm down,
hold position rigidly.
3.
Stop. Arm extended, palm down,
hold position rigidly.
4.
Emergency Stop. Same as (c), but
move hand rapidly, right and left.
5.
Raise Boom; Arm extended, fingers
closed, thumb• pointing upward
move hand up and down.
6.
Lower Boom. Same as (e), but with
thumb pointing down.
7.
Swing Boom. Arm extended, point
with finger in direction of motion.
8.
Bridge Travel. Arm extended, hand
open and slightly raised wave
forearm in direction of travel, while
facing in that direction.
9.
Rock or Trolley Travel. Palm
upward, fingers closed, thumb
pointing in direction of motion, jerk
and horizontally.
CHAPTER 5- CRANES AND OTHER HOISTING EQUIPMENT
b. Two-hand Signals:
1.
Hoist. Hold both arms horizontal at
sides, fully extended and move
upward and return.
2.
Lower. Hold both arms horizontal at
sides, fully extended and move out
and return.
3.
c.
Move Slowly. Same as (a) or (b),
but with other hand held near
(behind or below) the hand giving
the signal.
5.
Raise Boom and Lower Load.
Use (e) and (b) together.
6.
Lower Boom and Raise Load.
Use (f) and (a) together.
7.
Dog Off Load and Boom. Clasp
finger of one hand with fingers of
other, palm facing each other.
8.8
Hoist. Two short blasts.
2.
Lower. Three short blasts.
3.
Stop. One short blast.
4.
Emergency Stop. Series of short
blasts.
5.
Raise Boom. Four short blasts.
6.
Lower Boom. Fie short blasts.
8.
Swing Boom to Right. One long
and two short blasts.
9.
Swing Boom to Left. One long and
three short blasts.
Provision for Preventing Accidents Due to
Proximity of High Voltage Lines. The
provisions contained in Philippine Electrical
Code or Ordinances relative to clearances,
warning signs and other safeguards for the
prevention of electrical accidents due to
contacting high voltage lines shall be complied
with operation of voltage lines.
Section 9.0 Inspection
9.1
The employer shall require that fast moving
parts such as wire ropes, bearings gears,
frictions clutches, chain drives and other parts
subject to wear be inspected at adequate
intervals and any unsafe conditions must be
corrected. The Engineer must be required to
keep properly accomplished logbooks indicating
the date of inspections in the action made of
each and every equipment under his area of
supervision.
9.2
Mechanically and electrically operated brakes
shall be inspected periodically or as often as
necessary. Repairs and adjustments when
necessary should be made immediately.
9.3
Cranes handling molten metal shall be
inspected at least once a week when in use and
necessary repairs made accordingly.
Whistles Signals:
1.
Stop Booming. One short blast.
10. Stop Swinging Boom. One short
blast.
Stop. Hold both arms horizontal at
sides, fully extended. Same as (a)
without motion.
4.
7.
63
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
Chapter 6
ELEVATORS, DUMBWAITERS, ESCALATORS
AND MOVING WALKS
Car Door or Gate, Electric Contact An electrical
device, the function of which is to prevent operation of
the driving machine by a normal operating device
unless the car door or gate is in the closed position.
Section 1.0 Scope
—
This chapter provides definition of terms commonly
used in the subject of elevators, moving walks,
dumbwaiters, and escalators. It includes safety
provisions in the design, arrangement, installation and
operation of the equipment. Also in the chapter are
methods of determining the number of elevators
required as well as the maximum rated capacity and
loading of passenger elevator dumbwaiters.
Note: This function is subject to the modifications
specified in the Definition of Control, Two-Speed
Alternating Current.
A device or
Car Door or Gate Power Closer
assembly of devices which closes a manually opened
car door or gate by power other than by hand, gravity
springs, or the movement of the car.
—
Section 2.0 Definitions
Annunciator, Car An electrical signaling device in
the car which may visually or audibly indicate or call
attention to such information as the floor level, full or
overload conditions, manual or automatic operation,
alarm status and other such information regarding the
conditions at which the elevator signal register has
been actuated.
The top and the walls of the car
Car Enclosure
resting on and attached to the car platform.
—
—
Car Frame (Sling) The supporting frame to which
the car platform, upper and lower of guide shoes, car
safety, and the hoisting ropes or hoisting-rope
sheaves, or the hydraulic elevator plunger or cylinder
are attached.
—
Buffer A device assigned to stop a descending car
or counterweight beyond its normal limit of travel by
absorbing the momentum of descent of the car or
counterweight.
—
A car frame to which the
Car Frame, Oversiung
hoisting-rope fastenings or hoisting-rope sheaves, are
attached to the cross-head or the top member of the
car frame.
—
Bumper A device other than a buffer, designed to
stop a descending or falling car or counterweight
beyond its allowable lower limit of travel by absorbing
the energy or impact of descent.
—
A car frame all of whose
Car Frame, Sub-Post
the car frame.
below
located
are
members
—
Car Frame, Underslung A car frame to which the
hoisting-rope sheaves are attached at or below the car
platform.
—
Buffer, Spring A buffer utilizing a spring to absorb
the impact of the falling car or counterweight against
the elevator pit.
—
Car Platform The structure which forms the floor of
the car and which directly supports the load.
—
The load-carrying unit including its
Car, Elevator
platform, car, enclosure and car door or gate.
—
Clearance, Bottom Car The clear vertical distance
from the pit floor to the lowest structural or mechanical
part, equipment or device installed beneath the car
platform, except guide shoes or rollers, safety jaw
assemblies and platform aprons or guards, when the
car rests on its fully compressed buffers.
—
Car or Counterweight Safety A mechanical device
attached to the car frame or to an auxiliary frame, or
the counterweight frame, to stop and hold the car or
counterweight under one or more of the following
conditions: predetermined over speed, free-fall, or if
the suspension ropes slacken.
—
Clearance, Top Car The shortest vertical clearance
between the top of the car cross-head, or between the
—
64
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
top of the car where no cross-head, is provided, and
the nearest part of the overhead structure or any other
obstruction when the car floor is level with the top
terminal landing.
Door or Gate, Self-Closing
A manually opened
hoistway door or gate that automatically closes when
released.
—
Dumbwaiter
A hoisting and lowering mechanism
design to materials and other loads such as food,
laundry, etc., equipped with a car, which moves in
fixed guides and serves two or more fixed landings
through a hoistway. This equipment shall be designed
to carry small materials in a car, or partitioned or
shelved enclosure measuring no more than 0.86 m
2 of
net platform area; with a height no more than 1.2
meters and a maximum rated capacity no greater than
225 kg.
—
Clearance, Top Counterweight
The shortest
vertical distance between any part of the
counterweight structure and the nearest part of the
overhead structure or any other obstruction when the
floor is level with the bottom terminal landing.
—
Compensating-Rope Sheave Switch
A device
which automatically causes the electric power to be
removed from the elevator driving-machine motor and
brake when the compensating sheave approaches its
upper or lower limit of travel.
—
Dumbwaiter, Under Counter A dumbwaiter which
has its topmost landing located underneath a counter.
—
Control
The system governing the starting,
stopping, direction of motion, acceleration speed, and
retardation of the moving number.
—
Elevator A hoisting and lowering mechanism other
than a dumbwaiter or freight elevator which is design
to carry passenger or authorized personnel, in a
protected enclosure (elevator car) which moves along
fixed guides and serves two or more fixed landings on
a hoistway.
—
Control, Single-Speed Alternating Current
A
control for a driving machine induction motor which is
arranged to run at a single speed.
—
Controller
A device or group of devices which
serves to control in some predetermined manner the
apparatus to which it is connected.
Elevator, Freight
An elevator primarily used for
carrying freight and on which only the operator and the
person necessary for unloading and loading the freight
are permitted to ride.
—
Dispatching Device, Elevator Automatic
the principal function of which is to either:
—
—
A device,
Note: Its use is subject to the modification specified in
Sec. 6.4.8.
(a) Operate a signal in the car to indicate when the
car should leave a designated landing; or
Elevator, Inclined An elevator which travels at an
angle of inclination of 70 degrees or less from the
horizontal.
—
(b) Actuate its starting mechanism when the car is at
a designated landing.
Elevator, Multi-Deck
An elevator having two or
more compartment located one immediately above the
other.
—
Door, Bi-Parting A vertically or a horizontally sliding
door, consisting of two or more sections so arranged
that the sections or groups of sections open away from
each other.
—
Elevator, Hydraulic
A power elevator where the
energy is applied, by means of a liquid under
pressure, in a cylinder equipped with a plunger or
piston; the type of which as follows:
—
Door or Gate, Car or Landing The sliding portion of
the car, the hinged or sliding portion on the landing
through the hoistway enclosure which covers the
opening giving access to the car or the landing.
—
(a) Elevator, Direct—Plunger Hydraulic
A
hydraulic having a plunger or cylinder directly
attached to the car frame or platform.
—
Door or Gate, Manually Operated A hoistway door
or a car door or gate which is opened and closed by
hand.
—
(b) Elevator, maintained Pressure Hydraulic
A
hydraulic elevator having a plunger or cylinder
directly attached to the car frame or platform.
—
Door or Gate, Power Operated A hoistway door or
car door or gate which is opened and closed by means
of electric motor or other mechanical system utilizing
some motive power other than gravity, spring or
manual operation.
—
(c) Elevator, Electro-Hydraulic
direct-plunger
elevator where liquid under pressure is available
at all times for transfer into the cylinder.
—
65
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
The portion of a hoistway (shaft)
Hoistway, Blind
where normal landing entrances are not provided.
(d) Elevator, Roped-Hydraulic A hydraulic elevator
having its piston connected to the car with wire
ropes.
—
—
A hoisture (shaft) where normal
Hoistway Single
landing entrances are not provided.
—
An elevator designed to permit
Elevator, Scenic
exterior viewing by passengers while the car is
traveling.
—
Hoistway Enclosure The fixed structure, consisting
of vertical walls or partitions, which isolates the
hoistway from all other areas or from an adjacent
hoistway and in which the hoistway doors and door
assemblies are installed.
—
Elevator, Passenger An elevator used primarily to
carry persons other than the operator and persons
necessary for loading and unloading.
—
An electrical
Hoistway Door Electric Contact
device, the function of which is to prevent operation of
the driving machine by the normal operating device
unless the hoistway door is in the closed position.
Elevator, Pit That portion of a hoistway extending
from the threshold level of lowest landing door to the
floor at the bottom of the hoistway.
—
—
A power passenger
Elevator, Private Residence
elevator which is limited in size, capacity, rise, and
speed, and is installed in a private residence or in a
multiple dwelling as a means of access to a private
residence.
—
A device
Hoistway Door I Gate Locking Device
closed
the
in
gate
or
door
hoistway
a
secures
which
position and prevents it from being upended from the
landing side excerpt under certain specified
conditions.
—
Emergency Stop Switch A device located in the car
which when manually operated, causes the electric
power to be removed from the driving machine motor
and brake of an electric elevator or from the
electrically operated valves and/or motor of a hydraulic
elevator.
—
A series of hoistway door
Hoistway-Unit System
contacts or hoistway
electric
interlocks, hoistway door
locks and electric
mechanical
door combination
the function of
thereof,
combination
a
or
contacts,
which is to prevent operation of the driving machine by
the normal operating device unless all hoistway doors
are in the closed position and, are locked in the closed
position.
—
An entrance in
Entrance Locked Out of Service
locked by
mechanically
is
door
hoistway
the
which
means other than the interlock to prevent the door
being opened from the car side without keys or special
equipment.
—
Hoistway Door Combination Mechanical Lock and
A combination mechanical and
Electric Contact
two related, but entirely
with
device
electrical
independent functions, which are:
—
A power-driven, inclined continuous
Escalator
stairway used for raising or lowering passengers.
—
(a) To prevent operation of the driving-machine by the
normal operating device unless the hoistway door
is in the closed position; and
Escalators, Tandem Operation Escalators used in
series with common intermediate landings.
—
(b) To lock the hoistway door in the closed position
and prevent it from being opened from the landing
side unless the car is within the landing zone.
Factory of Safety The ratio of the ultimate strength
to the working stress of a member under maximum
static loading, unless otherwise specified in a
particular rule.
—
Note: As there is no positive mechanical connection
between the electric contact and the door-locking
mechanism, this device ensures only that the door will
be closed, but not necessarily locked, when the car
leaves the landing. Should the lock mechanism fail to
operate as intended when released by a stationary or
retiring car-cam device, the door can be opened from
the landing side even though the car is at the landing.
If operated by the normal operating device unless all
hoistway doors are in the closed position and, where
A switch, located at a
Hoistway Access Switch
landing, the function of which is to permit operation of
the car with the hoistway door at this landing and the
car door or gate open, in order to permit access to the
top of the car or to the pit.
—
An opening through a building or
Hoistway!Shaft
of elevators, dumbwaiters, or
travel
the
for
structure
material lifts, extending from the pit floor to the roof or
flow above.
—
66
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
so required by this code, are locked in the closed
positions.
(c) Traction Machine A direct driven in which the
motion of the car is obtained through friction
between the suspension and a traction sheave.
—
Indicator, Passenger Waiting
An indicator which
show a which landing and for which direction elevator
hall stop-or-signal calls have been registered and are
unanswered.
—
(d) Gearless-Traction Machine A traction machine,
without intermediate gearing, which has the
traction sheave and the brake drum mounted
directly on the motor shaft.
—
Landing, Elevator or Material Lift That portion of a
floor balcony or platform used to receive and
discharge passengers or freight.
—
(e) Winding-Drum Machine
A geared-drive
machine in which the suspension ropes are
fastened to and wind on a drum.
—
Landing Zone A zone extending from a point 457
mm below an elevator or material lift landing to a point
457 mm above landing.
—
(f) Worm-Geared Machine
A geared-drive
machine in which the energy from other motor is
transmitted to the driving sheave or drum through
worm gearing.
—
Leveling
Controlled car movement toward the
landing, within the leveling zone, by means of a
leveling device, which vertically aligns the car-platform
sill relative to the hoistway landing sill to attain a
predetermined accuracy.
—
(g) Indirect-Drive Machine
An electric driving
machine, the motor of which is connected
indirectly to the driving sheave, drum or shaft by
means of a belt or chain through intermediate
gears.
—
Leveling Device, One-Way Automatic
A device
which corrects the car level only in case of under-run
of the car, but will not maintain the level during loading
and unloading.
—
Material Lift
A hoisting and lowering mechanism
normally classified as an elevator has been modified
to adapt it for the automatic transfer device.
—
Leveling Device, Two-Way Automatic Maintaining
A device which corrects the car level on both under
run and over-run, and maintains the level during
loading and unoading.
Moving Walk
A power-driven device made of a
continuous belt treadway or pallets used to convey
passengers and/or materials on a horizontal plane
from one point to another; the types of which as
follows:
—
—
Leveling Zone The limited distance above or below
an elevation or material lift landing with which the
leveling device is permitted to cause movement of the
car toward the landing.
—
(a) Moving Walk, Belt Type A moving walk with a
power driven continuous belt treadway.
—
Machine Drive
The power unit which applies the
energy necessary to raise or lower an elevator or
dumbwaiter.
(b) Moving Walk, Belt Pallet Type A moving walk
with a series of connected and power-driven
pallets to which a continuous treadway is
fastened.
—
—
Machine Drive, Electric
One where the energy is
applied by an electric motor. It includes the motor,
brake, and the driving sheave or drum together with its
connecting gearing, belt or chain, if any, and can be
classified as follows:
—
(c) Moving Walk, Pallet Type A moving walk with a
series of connected and power-driven pallets
which together constitutes a treadway.
—
Non-Stop Switch, Elevator A switch, which when
operated will prevent the elevator from marking
registered landing stops.
—
(a) Direct-Drive Machine
An electric driving
machine, the motor which is directly connected
mechanically to the driving sheave, drum, or shaft
without the use of the belts or chains, either with
or without intermediate gears.
—
Operator, Automatic Operation wherein the starting
of the elevator car is effected in response of the
momentary actuation of operating devices at the
landing, and/or operating devices in the car identified
with the landings, and/or in response to an automatic
starting mechanism and wherein, the car is stopped
automatically at the landings.
—
(b) Geared-Drive Machine A direct drive machine
in which the energy is transmitted from the motor
to the driving sheave drum or shaft through
gearing.
—
67
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
The car switch, push button,
Operating Device
lever or other manual device used to actuate the
control.
An assembly of
Starter Control Panel, Elevator
devices by means of which the starter may control the
manner in which an elevator or group of elevators
function.
All the structural members
Overhead Structure
platforms, etc. supporting the elevator machinery,
sheaves and equipment at the top of the hoistway.
Switching of circuits by means of
Static Switching
devices.
solid state
—
—
—
—
A button or
Stopping Devices, Elevator Landing
other device, located at an elevator landing which
when actuated, causes the elevator to stop at that
floor.
An electrical or
Parking Device, Elevator
mechanical device the function of which is permit the
opening from the landing side of the hoistway door at
any landing when the car is within the landing zone of
that landing. The device may also be used to close
the door.
—
—
Rope Equalizer, Suspension A device installed on
an elevator car or counterweight to equalize
automatically the tensions in the suspension wire
ropes.
A
Terminal Speed Limiting Device, Emergency
a
car
as
the
speed
reduces
automatically
device which
approaches a terminal landing, independently of the
functioning of the operating device, and the normalterminal stopping device, if the latter fail to slow down
the car as intended.
A device
Rope-Fastening Device, Auxiliary
attached to the c,ar or counterweight or to the
overhead dead-end rope-hitch support which will
function automatically to support the car or
counterweight in case the regular wire-rope fastening
falls at the point of connection to the car or
counterweight or at the overhead dead-end hitch.
A device
Terminal Stopping Device, Emergency
removed
be
power
to
which automatically causes the
and
motor
machine
driving
elevator
electric
from an
brake at a pre-determined distance from the terminal
landing, and independently of the functioning of the
operating device and the normal terminal stopping
devices does not slow down the car as intended.
A car or counterweight
Safety, Self-Resetting
safety released and reset by movement in the up
direction.
Terminal Stopping Device, Machine Final (Stop
A final-terminal stopping device
Motion Switch)
driving machine.
by
the
directly
operated
Automatic operation
Single Automatic, Operation
by means of one button in the car for each landing
served and one button at each landing, so arrange
that f any car of landing button has been actuated, of
actuation of any other car or landing operating button
will have no effect of the operation of the car until the
response to the first button has been completed.
A device or
Terminal Stopping Device, Normal
devices to slow down and stop an elevator,
dumbwaiter, or material lift car automatically at or near
a terminal landing independently of the functioning of
the operating device.
—
—
—
—
—
—
—
—
Top Runby (Direct-Plunger Hydraulic Elevator)
The distance the elevator car can run above its top
terminal landing before the plunger strikes the
mechanical stop.
—
Signal Device, Elevator Car Flush One providing a
signal light in the car, which is illuminated when the
car approaches the landings at which a landing signal
registering device has been actuated.
—
A panel or panels used to close a
Transom
hoistway enclosure opening above a hoistway
entrance.
—
Signal System, Elevator One consisting of buttons
or other devices located at the landing which when
actuated by a waiting passenger illuminate a flash
signal or operate an annunciator in the car indicating
floors at which stops are to be made.
—
The vertical distance between the
Travel (Rise)
bottom terminal landing and the top terminal landing of
an elevator, dumbwaiter, escalator, material lift, or
inclined lift.
—
A device which automatically
Slack-Rope Switch
causes the electric power to be removed from the
elevator driving machine motor and brake when the
suspension ropes of a winding-drum machine become
slack.
—
A cable made up of electric
Travelling Cable
electrical connection
provides
conductors, which
between an elevator, dumbwaiter, or material lift car
and fixed outlet in the hoistway or machine room.
—
68
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
Section 3.0 Electric Elevators
3.1
Construction
Enclosure
a.
of
Hoistway and
The fire resistance ratings of the
entrances shall be not less than 1 %
hour.
Hoistway
The fire resistance rating of a
hoistway
opening
protective
assemblies other than elevator
entrances shall be not less than 1 %
hour as determined with tests
conducted in accordance with
ANSI/ASME E152 Methods of Fire
Tests of Door Assemblies.
Enclosure of Hoistways:
1.
Fire-Resistive
Construction
Required. Hoistways shall be
enclosed throughout their height
with fire-resistive enclosures, and all
hoistways landing openings shall be
protected with fire-resistive entrance
assemblies.
The fire resistance shall not be less
than required by Local Code such
as the National Building Code,
National Fire Code and the
Philippine Electrical Code.
Exceptions:
(a) Partitions between fire-resistive
hoistways and machine rooms
having fire-resistive enclosures
and which are located at a side
of or beneath the hoistway, may
be
of
un-perforated
non
combustible material at least
equal to 1.52 mm sheet steel in
strength and stiffness with
openings therein essential for
ropes, drums, sheaves and
other elevator equipment.
3.
(b) Elevators which are entirely
within one story or which pierce
no solid floors and serve two or
more open galleries, book
stacks, etc., in building such as
power-houses, libraries, open
towers, and similar structures.
(c) Observation elevators which are
adjacent to a building wall
without penetrating the separate
fire-resistive areas of the
building (Fire-resistive entrance
assemblies and a fire resistance
rated wall per Sec. 6.3.1 (b)
shall be used).
2.
Non-Fire-Resistive
Enclosures.
Where
fire-resistive
hoistway
enclosures and entrances are not
required by Sec. 6.3.1.1 (a).
Enclosure and entrances shall be
unperforated to a height of 1 830
mm above each floor or landing and
above the treads of adjacent
stairways. Enclosures shall be so
supported and braced as to deflect
not over 25 mm when subjected to a
force of 45 kg applied horizontally at
any point. Unperforated metal
enclosures shall be equal to or
stronger than 1.2 mm sheet steel.
Open work enclosures may be used
above the 1 830 mm level and shall
be of either wire grille at least 2.30
mm diameter steel wire of expanded
metal at least 2.30 mm in thickness.
Glass curtain walls may be used in
elevator hoistways provided the
panels are of laminated glass.
4.
Fire Resistance Rating. The fire
resistance rating of the hoistway
enclosure, exclusive of entrances
and protective assemblies in other
openings, shall not be less than the
required by the National Building
Code.
69
Strength of Enclosure. The
hoistway enclosure adjacent to a
landing opening shall be of sufficient
strength to maintain in true lateral
alignment the hoistway entrances.
Operating mechanism and locking
devices shall be supported by the
building wall, if load bearing, or by
other building structure. Adequate
consideration shall be given to
pressure exerted on hoistway
enclosures as a result of windage
and/or elevator operation.
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
3.2
3.3
Hoistway Protection in Case of Fire.
Hoistway of elevators shall be provided in cases
of fire as required by the local codes such as the
National Building Code, National Fire and the
Philippine Electrical Code.
3.4
Hoist for all elevators shall be substantially
enclosed throughout their height, and there shall
be no openings except for necessary doors,
windows or skylights.
3.5
Hoistway for elevators outside building shall be
substantially enclosed to a height of at least
3 000 mm provided that the enclosure shall be
continuous to the top of any side on which there
is access to the cage.
Location of Floor. The floor shall be
located:
3.6
Above or level with the tope of the
machine beams where the machine
is located over the hoistway;
The enclosure shall either be a continuous wall
or substantial grill work, metal bars, or wood
slats.
3.7
Openings fixed enclosures shall not exceed 50
mm in their lesser dimensions, at all places
where moving cars, counter-weights, or sliding
doors present hazard they shall not exceed 10
mm in their lesser dimensions.
3.8
Hoistway enclosures and hoistway doors and
door assemblies shall be of fire-resistive
construction of not less than 1-hour fire
resistance.
3.9
Where four or more elevators serve or the same
portion of a building, they shall be located in not
less than two (2) hoistway and in no case shall
more than four (4) elevators be located in any
one hoistway.
Floor Over Hoistways:
a.
Where Required. A metal or concrete floor
shall be provided at the top of the hoistway.
Exceptions: Floors are not required below:
b.
1.
Secondary and deflecting sheaves
of traction-type machines located
over the hoistway.
2.
Overhead sheaves, governors, and
other equipment where the elevator
machine is located below or at the
side of the hoistway.
1.
2.
c.
d.
Below the overhead sheaves where
the machine is not located over the
hoistway.
Strength of Floor. The floor shall be
capable of sustaining a concentrated load of
136 kg on any 2 580 mm area and in
addition where it constitutes the floor of the
main or secondary level machinery space, it
shall be designed for a live load of not less
than 611 kg/rn in all open areas. A sign
stating the maximum allowable load of
which the floor is designed shall be
permanently displayed in all main and
secondary machine-room spaces. The sign
shall be of metal with black letters and
figures at least 100 mm high on a white
background.
3.10 Window and Skylights:
a.
Construction of Floors. Floors may be of
concrete, or may be of metal construction
with or without perforations. Metal floors
shall conform to the following:
1.
If of bar-type grating, the openings
between bars shall reject a ball 20
mm in diameter.
2.
If of perforated sheet metal or of
fabricated open work construction,
the openings shall reject a ball 25
mm in diameter.
Window and Skylight Frames and Sash.
Windows in the walls of hoistway enclosures
Frames and sashes of
are prohibited.
windows in machine rooms and skylights
shall be of metal.
1.
70
A guard
Skylights Guards.
securely anchored to the supporting
structure, consisting of a wire mesh
screen of at least 2.325 mm
diameter steel wire with openings
which will reject a ball 25 mm in
diameter, or an expanded metal
screen of equivalent strength and
open area, shall be installed above
every elevator skylight. A similar
screen of at least 1.205 mm
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
diameter steel wire, or of expanded
metal of equivalent strength and
open area, shall be installed below
every elevator skylight.
from the landing except with special emergency
key.
4.5
Landing opening in passenger-elevator hoistway
enclosure shall be protected preferably by
sliding doors, combination sliding and swing
doors, or swinging doors.
4.6
Access to Machine Rooms and Machinery
Spaces:
Section 4.0 Machine Rooms and
Machinery Spaces
4.1
Enclosure Required:
a.
4.2
b.
4.4
a.
General Requirements. A permanent safe
and convenient means of access to elevator
machine rooms and overhead machinery
spaces shall be provided for authorized
persons.
b.
Where the passage is over a sloping roof
having slope exceeding 15 degrees from the
horizontal, an unobstructed, permanent and
substantial walkway not less than 610 mm
wide, equipped on at least one side with a
standard railing not less than 1 067 mm
high, shall be provided from the building exit
door at the roof level to the means of access
to machine room or machinery spaces.
Railings shall conform to the requirements
of ANSI A12.1.
Equipment in Machine Rooms
a.
4.3
Enclosure Required for Elevators Having
Non Fire-Resistive Hoistway Enclosure.
Spaces containing
control
machines,
equipment, sheaves, and other machinery
shall be enclosed with non combustible
material extending to a height of not less
than 1 830 mm. Openwork material, if used,
shall reject a ball 51 mm in diameter.
Equipment Permitted in Machinery and
Control Spaces. Elevator machine and
control equipment may be located in a room
or space containing other machinery and
equipment essential to the operation of the
building; provided that they are separated
from the other machinery or equipment by a
substantial metal grille enclosure not less
than 1 830 mm high with a self-closing and
self-locking door. The grille enclosures shall
be of a design which will reject a baIl 51 mm
in diameter.
4.7
Equipment Prohibited in Machine Room.
Where the elevator machine and control
equipment are not located at the top of the
hoistway, only machinery and equipment
required for the operation of the elevator
shall be permitted in the elevator machine
room.
Headroom in Machine Rooms and Overhead
Machinery Spaces. Elevator machine rooms
and machinery spaces not located over the
hoistway shall have a clear headroom of not
less than 2 130 mm.
Where a floor is provided at the top of the
hoistway (see Sec. 4.2), elevator machine
rooms and overhead machinery spaces above
such floor shall have a clear headroom of not
less than the following:
Where machine room are provided over elevator
shaftways
they
shall
be
substantially
constructed with sufficient room for repair and
inspection and access shall be by means of iron
ladder or stairs where the machine room
entrance is more than 610 mm above the
adjacent floor or roof surface. The angle of
incline of such ladder or stair shall not exceed
60° horizontal.
Landing doors for power driven elevators shall
be provided with interlocks to hold the elevator
car immovable while any landing. door is open
and to make it impossible to open any landing
door when the car is more than 80 mm away
71
a.
Machine, control,
rooms, 2 130 mm.
b.
Spaces containing overhead, secondary or
deflecting sheaves, and governors, signal
machines, or other equipment, 1 372 mm.
c.
Spaces containing overhead, secondary and
deflecting sheaves, the machine and
supporting beams may encroach on the
required headroom provided there is a
clearance of not less than 914 mm between
the underside of such beams and the top of
the floor.
and
motor-generator
__
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
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4.8
Where practicable the light control switch
shall be located on the lock jamb side of the
access door.
Lighting and Ventilation of Machine Room
and Machinery Spaces.
(a) Lighting. Permanent electric lighting shall
be provided in all machine rooms and
machinery spaces.
(b) Ventilation for Machinery and Control
Machine rooms shall be
Equipment.
provided with natural or mechanical
ventilation to avoid overheating of the
electrical equipment and to insure safe and
normal operation of the elevator.
The illumination shall be not less than 108
lux at the floor level, The lighting control
switch shall be located within easy reach of
the access to such rooms or spaces.
72
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
4.9
Storage of Materials in Machine and Control
Room. Elevator machine and control rooms
shall be maintained free of refuse, and shall not
be used for the storage of articles unnecessary
for the maintenance or operation of the elevator.
Flammable liquids having a flash point of less
than 43.3°C shall not be kept in such rooms.
(a) All risers and returns shall be located
outside these spaces.
(b)
(c) Shut off valves shall be provided in
accessible locations outside these
spaces.
Section 5.0 Electrical Wiring, Pipes, and
Ducts in Hoistway and Machine Rooms
5.1
Wiring, Raceways, and Cables in Hoistways.
Main feeders for supplying power to the elevator
shall be installed outside the hoistway.
4.
5.3
Only such electrical wiring, raceways, and
cables used directly in connection with the
elevator, including wiring for signals, for
communication with the car, for lighting, heating,
air conditioning, and ventilating the car, for lowvoltage fire-detecting systems, for pit sump
pumps, and for heating and lighting the
hoistway, may be installed inside the hoistway.
5.2
Installation of Pipes or Ducts Conveying
Gases, Vapors or Liquids in Hoistways,
Machine Rooms, or Machinery Spaces. Pipes
of ducts conveying gases, vapors, or liquids and
not used in connection with the operation of the
elevator shall not be in any hoistway, machine
room, or machinery space.
a.
5.4
a.
2.
3.
Ducts of heating, cooling, ventilating and
venting these spaces only may be installed
in the machine room and machinery space.
Pipes for sprinklers only may be installed in
these spaces subject to the following:
Beams
and
Supports
Required.
Machines, machinery, and sheaves shall be
so supported and maintained in place to
prevent any part from becoming loose or
displaced under the conditions imposed in
service.
Supporting beams, if used, shall be of steel
or reinforced concrete. Beams are not
required under machines, sheaves, and
machinery or control equipment which are
supported on floor provided such floors are
designed and installed to support the load
imposed thereon.
(a) Heating pipes shall convey only low
pressure steam [34 Kpa or less] or hot
water [100°C or less]
(c) Traps and shut-off valves shall be
provided in accessible locations outside
the hoistway.
In machine rooms and secondary machinery
spaces, exposed gears, sprockets, tape of
rope sheaves or drums of selectors, floor
controllers or signal machines, and their
driving ropes, chains or tapes, shall be
guarded to protect against accidental
contact.
Machinery and Sheave Beams, Supports and
Foundations:
Steam and hot water pipes may be installed
in
hoistways,
machine
rooms,
and
machinery spaces for the purpose of heating
these areas only, subject to the following:
(b) All risers and return pipes shall be
located outside the hoistway.
Piping for pit and sump pumps may be
installed.
Guarding of Exposed Auxiliary Equipment:
Exceptions:
1.
Branch lines in hoistway shall supply
sprinklers at not more than one floor
level.
b.
Loads:
1.
Overhead Beams, Floors, and
Their Supports. Overhead beams,
floors, and their supports shall be
designed for not less than the sum
of the following loads:
(a) The loads resting on the beams
and supports which
shall
include the complete weight of
the
machine,
sheaves,
controller, governor and any
other equipment together with
S
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALK
(see Sec. 6.3.6.3) shall conform to
Section 6.3.1.1.
that portion, if any of the
machine-room floor supported
thereon.
(b) Two times the sum of the
tensions in all wire ropes
supported by the beams with
rated load in the car.
2.
Foundations, Beams, and Floors
for Machinery and Sheaves Not
the
Over
Directly
Located
for
ts
suppor
The
Hoistway.
located
s
sheave
machines and
below or at the sides of the hoistway
following
the
have
shall
requirements:
c.
(b) The sheave beams and the
foundation bolts shall withstand
vertical
the
times
two
component of the tension in all
ropes on the
suspension
foundation or beams less the
weight of the machine or
sheaves.
(c) The sheave beams and the
foundation bolts shall withstand
horizontal
two times the
component, if any, of the
tension in all suspension ropes
passing over sheaves or drums
on the foundation or beams.
(d) The foundation shall withstand
two times the over-turning
moment, if any, developed by
the
all
in
tensions
the
suspension ropes passing over
sheaves or drums on the
foundations or beams.
Where Required. A pit shall be provided for
every elevator.
b.
Design and Construction of Pits.
1.
be
3.
Drains connected directly to sewers
shall not be installed in elevator pits.
4.
Elevator pits shall be water-proofed
with at least 3/16” steel plate on all
sides at a height of not less than
1.20 meters including the pit floor.
or
without
Access to Pits. Safe and convenient
access shall be provided to all pits, and shall
conform to the following:
1.
Access shall be by means of the
lowest hoistway door or by means
of a separate pit access door.
2.
There shall be installed in the pit of
each elevator where the pit extends
more than 914 mm below the sill of
the pit access door, a fixed vertical
ladder of non-combustible material,
located within reach of the access
door. The ladder shall extend not
less than 1067 mm above the sill of
the access door, or handgrips shall
be provided to the same height.
3.
Pits shall be accessible only to
authorized persons.
Where a separate pit access door is
provided, it shall be self-closing and
provided with a spring-type lock
arranged to permit the door to be
opened from inside the pit without a
Such doors shaD be kept
key.
locked.
Pits.
a.
shall
The floor of the
approximately level.
Exception: Sumps with
pumps may be installed.
(a) The foundation shall support the
total weight of the machine,
sheaves, and other equipment,
and the floor if any.
5.5
pit
2.
The construction of the pit walls, the
pit floor, and any pit access doors
74
d.
Illumination of Pits. A permanent lighting
fixture shall be provided in all pits, which
shall provide an illumination of not less than
54 lux at the pit floor. A light switch shall be
provided and shall be so located as to be
accessible from the pit access door.
e.
Stop Switch in Pits. There shall be
installed in the pit of each elevator an
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
enclosed stop switch or switches meeting
the requirements of Section 6.D.11.3(g).
b.
The switch shall be so located as to be
accessible from the pit access door. Where
access to the pits of elevators in a multiple
hoistway is by means of a single access
door, the stop switch for each elevator shall
be located adjacent to the nearest point of
access to its pit from the access door.
Bottom Runby for Counterweighted
Elevators. The bottom runby of cars and
counterweights shall be not less than the
following:
1.
Exceptions:
(a) Where
practical
difficulties
prevent a sufficient pit depth or
where a top clearance cannot
be provided to obtain the runby
specified, it may be reduced.
In elevators where access to the pit is
through the lowest landing hoistway door a
stop switch shall be located approximately
457 mm above the floor level of the landing,
within reach from this access floor and
adjacent to the pit ladder if provided. When
the pit exceeds 2010 mm in depth, an
additional stop switch is required adjacent to
the pit ladder and approximately 1220 mm
above the pit floor. Where more than one
switch is provided, they shall be wired in
series.
f.
5.6
(b) Where spring-return type oil
buffers are used, the runby may
be eliminated by amounts not
be eliminated so that the buffers
are compressed by amounts not
exceeding 610 mm when the
car floor is level with the
terminal landings.
Minimum Pit Depths Required. The pit
depth shall be not less than is required for
the installation of the buffers, compensating
sheaves if any, and all other elevator
equipment located therein, and to provide
the minimum bottom car clearance and
runby required by Section 6.C.7.
2.
Where spring buffers are used:
(a) Where generator-field control is
used, 152 mm.
c.
Bottom and Top Clearances and Runbys for
Elevator Cars and Counterweights
a.
Where oil buffers are used, 152
mm.
Bottom Car Clearances. When the car
rests on its fully compressed buffer, there
shall be a vertical clearance of not less than
610 mm between the pit floor and the lowest
structural or mechanical part, equipment or
device installed beneath the car platform
except guide shoes or rollers, safety-jaw
assemblies, and platform aprons, guards, or
other equipment located within 305 mm
horizontally from the sides of the car
platform (see Apendix D, Fig. D3).
Bottom Runby for Uncounterweighted
Elevators.
The
bottom
runby
of
uncounterweighteci elevators shall be not
less than the following:
1.
76 mm where the rated speed does
not exceed 0.13 m/s.
(a) 152 mm where the rated speed
exceeds 0.13 mIs.
d.
Top Counterweight Clearances. The top
counterweight clearance shall be not less
than the sum of the following:
1.
Trenches and depressions or foundation
encroachments permitted by the exceptions
in Section 6.3.6.2 shall not be considered in
determining this clearance. When the car
rests on its fully compressed buffer, no part
of the car or any equipment attached thereto
shall strike any part of the equipment
located therein.
The bottom car runby.
(a) The stroke of the car buffer
used.
(b) 152 mm
(c) Where an oil buffer is used for
the car and no provision is
made to prevent the jump of the
75
ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
CHAPTER 6
counterweight at
engagement, add:
car
hoistway, shall be not less than 51
mm.
buffer
one-half the gravity stopping
distance based on 115% of the
rated speed.
4.
Between Cars and Landing Sills.
The clearance between the carplatform sill and the hoistway edge
of any landing sill, or the hoistway
side of any vertically sliding
or
counterweighted
counterbalanced hoistway door or of
sliding
vertically
any
counterbalanced biparting hoistway
door, shall be not less than 13 mm
where side guides are used, and not
less than 19 mm where corner
guides are used. The maximum
clearance shall be not more than 38
mm.
5.
Clearances Between Loading
Side of Car Platforms and
The
Enclosures.
Hoistway
clearance betweem the edge of the
car-platform sill and the hoistway
enclosure or fascia plate for the full
width of the clear hoistway-door
opening shall be not more than 127
mm.
(d) Where car spring buffers are
used, add one-half the gravity
stopping distance based on
governor tripping speed.
Exceptions: (Sec. 6.3.7.4): Section
6.3.7.4 (a) and (b) may be modified
correspondingly when the bottom car
runby has been reduced or eliminated
as provided in Section 6.3.7.2 (a),
Exceptions (1) and (2).
e.
Overhead Clearances Where Overhead
Beams Are Not Over Car Crosshead.
Where overhead beams or other overhead
hoistway construction, except sheaves, are
located vertically over the car, but not over
the crosshead, the following requirements
shall be met:
1.
f.
Such beams or construction shall be
located not less than 610 mm
horizontally from the crosshead.
Horizontal
Clearances
1.
2.
3.
Car
and
Where vertically sliding
Exception:
hoistway doors are installed, the
clearance specified may be increased to
190 mm. For heavy duty, elevators or
extra-wide door openings, the clearance
may be increased where necessary,
subject to the approval of the enforcing
authority.
Counterweight
Hoistway
Between Car and
clearances
The
Enclosures.
between the car and the hoistway
enclosure shall be not less than 19
mm except on the sides used for
loading and unloading.
6.
Between Car and Counterweight
and Counterweight Screen. The
clearance between the car and the
counterweight shall be not less than
25 mm. The clearance between
the
and
counterweight
counterweight screen and between
the counterweight and the hoistway
enclosure shall be not less than 19
mm.
g.
Measurement of Clearances. The
clearances specified in Sec. 6.C.8
shall be measured with no load on
the car platform.
Protection
Openings
1.
of
Hoistway-Landing
Passenger
for
Entrances
Elevators
Freight
Elevators and
authorized to carry employees:
(a) Horizontal slide, single or multi
section.
Multiple
in
Cars
Between
Hoistway. The running clearance
any
and
the cars
between
equipment attached thereto, of
elevators operating in a multiple
(b) Swing, single-section.
(c) Combination
and swing.
76
horizontal
slide
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
(d) Power-operated, vertical slide
biparting counterbalanced, or
vertical slide counterweighted
which slide down to open,
where located at entrances
used by passenger (see Section
6.D.8.5).
c.
Mounting used between panel sections shall
be of non-combustible material and of
substantial construction.
d.
Panel opening shall be glazed with clear
wire glass not less than 6.3 mm thick.
e.
The center of the panel shall be located not
less than 1370 mm nor more than 1680 mm
above the landing; except that for vertically
sliding biparting counter-balanced doors, it
shall be located to conform with the
dimensions specified insofar as the door
design will permit.
f.
The vision panels in horizontally swinging
doors shall be located for convenient vision
when opening the door from the car side.
g.
Wire-glass panels in power-operated doors
shall be substantially flush with the surface
of the landing side of the door.
(e) Hand or power-operated vertical
slide which slide up to open.
2.
For Freight Elevators. Entrances
shall be one of the following types:
(a) Horizontal slide, single or multisection.
(b) Swing, single-section.
(c) Combination
and swing.
horizontal
slide
(d) Center-opening,
two-section
horizontal swing (subject to
restrictions of Section 6.C.9.3).
5.8
Hoistway
Door Locking Devices
Hoistway Door Power Operators
—
a.
(e) Vertical slide counterweighted,
single or multi-section.
3.
Limitations of Use of Double
Swing Entrances.
a.
(b) For
freight
elevators
not
accessible to the general public
which can be operated from
outside the hoistway, and which
are
located
in
factories,
warehouses,
garages
and
similar industrial buildings.
Hoistway Door Vision Panels:
a.
b.
Locking Devices. Doors shall be provided
with door locking devices, hoistway access
switches and parking devices.
5.9 Entrances, Horizontal Slide Type
(a) For freight elevators which can
be operated only from the car;
or
5.7
and
Landing Sills. Landing Sills shall:
1.
Be of metal and of sufficient
strength to support the loads to be
carried by the sills when loading and
unloading the car, and be secured
in place;
2.
Be substantially flush with the floor
surface of the elevator landings and
so designed and maintained as to
provide a secure foothold over the
entire width of the door opening.
Exceptions [Section 6.C.9.6 (a) (2)].
The area of any single vision panel shall be
not less than 0.016 m
2 and the total area of
one or more vision panels in any hoistway
door shall be not more than 0.051 m
.
2
(a) Where necessary, sill may be
beveled or the landing floor may
be ramped. The angle with the
horizontal shall be not greater
than 76 mm in 305 mm for
beveled sills nor greater than 25
mm in 305 mm for ramped
landings.
Each clear panel opening shall reject a ball
152 mm in diameter.
77
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
3.
(b) The top surface or beveled sills
shall not be more than 38 mm
floor
adjacent
the
above
surface.
1.
Stops shall be provided in the
entrance assembly to prevent
hangers from over-running the end
of the track.
Track
and
Tracks
Hanger
Supports. The tracks and their
supports and fastenings for power
operated doors shall be constructed
to withstand without damage or
appreciable deflections, an imposed
static load equal to four times the
weight of each panel as applied
successively downward and upward
at the vertical centerline of the
panel.
2.
For power-operated doors, they
shall be constructed to withstand,
without damage or appreciable
deflection, and imposed static load
equal to four times the weight of
each panel as applied successively
downward and upward at the
vertical centerline of the panel.
5.11 Panels. Panels shall conform to the following:
a.
4.
Entrance Frames. Frames shall
conform to the following:
(a) if used, they shall overlap the
wall surface on the hoistway
side and provide a uniform
surface on the hoistway side of
the wall parallel to the plane of
the panels.
The panels shall overlap the top and sides
of the opening and each other, in the case
of multispeed entrances, by not less than 16
mm.
1.
The clearance between the panel and
the frame and between related panels of
multispeed entrances shall not exceed
9.5 mm.
2.
The leading panel edge of side-opening
entrances shall not close into pockets in
the strike jamb and shall be smooth and
free of sharp projections.
3.
The meeting panel edges of centeropening entrances shall be smooth and
free of sharp projections.
securely
be
shall
(b) They
anchored to the sills, and to the
building structure or to the track
supports.
Anchors and fastenings to suit
are
construction
wall
the
The head of the
required.
entrance frames shall not be
used to support the weight of
the wall over the frame.
The meeting panel edges of centeropening entrances shall be protected
with not less than one resilient male
member extending the full height of the
The meeting edges may
panel.
interlock by not more than 9.5 mm.
made of
be
(c) They shall
noncombustible material with a
melting point no less than
Combustible material
982°C,
not more than 1.6 mm thick or
point
melting
low
noncombustible material may
be applied for decorative
purposes.
5.10 Hangers.
following:
a.
Hangers
shall
conform
to
4.
The panels shall have no area or
molding depressed or raised more than
6.3 mm from the exposed surface,
unless they are parallel to the direction
of panel motion. Areas depressed or
raised more than 3.2 mm from the
adjacent area and not parallel to the
direction of panel motion, shall be
beveled at not more than 30° to the
panel surface.
5.
Combustible materials not more than
1.6 mm thick or low melting point
noncombustible materials may be
the
Means shall be provided to prevent the
hangers from overrunning the end of the
track.
78
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
applied to the panel
decorative purposes.
6.
7.
surface
for
transmitted to the rails as a result of loading
and unloading operations.
The entrance assembly shaH be capable
of withstanding, a force of 113 kg
applied on the landing side at right
angles to and approximately at the
center of a panel. This force shall be
distributed
over
an
area
of
approximately 102 mm by 102 mm.
There
shall
be
no
appreciable
permanent displacement or deformation
of any parts of the entrance assembly
resulting from this test.
d.
1.
(a) be of metal and of
sufficient
strength
to
support the loads to be
carried by the sills when
loading and unloading car
can be secured in place.
Rails. The panel guide rails shall be
securely fastened to the building structure
and the entrance frame, at intervals,
throughout their entire length.
to
the
The panels shall be constructed of
noncombustible material.
(c) They shall be provided with
means to stop the closing
panels when the distance
between
the
closing
rigid
members of the panel is not
less than 19 mm.
(b) be firmly anchored to the
building
structure
in
substantially the same
place as the elevator
landing floor.
c.
conform
(b) Panels
of
biparting
counterbalanced
entrances
shall conform to the following:
Landing Sills. Landing Sills shall:
Entrance Frames. The uprights and lintels
used to frame the opening shall be securely
fastened to the building structure at the top
and bottom and to the wall.
shall
(a) The lower panel of vertical
biparting entrances and the top
of the panel of vertical slide
entrances which slide down to
open, shall be provided with a
truckable sill designed for the
loads specified in Section
6.3.9.9 (a) (1). Provisions shall
be made to transmit the panel
sill to the building structure.
If any combustible material or low
melting point material, is used in the
entrance
assembly,
should
be
consumed or should melt, the allowable
movement towards the hoistway of the
panels from their normal operating
position shall not exceed 16 mm at the
top or at the bottom.
b.
Panels
Exception: A structural core made of
combustible material may be used if
covered with not less than 0.455
mm sheet metal.
5.12 Entrance, Vertical Slide Type
a.
Panels.
following:
(ci) A fire-resistive, non-shearing,
and non-crushing member of
either the meting or overlapping
type shall be provided on the
upper panel to close the
distance between the rigid door
sections when in contact with
the stops.
(e) Rigid members which overlap
the melting edge and center
latching devices are prohibited.
(f) The
panels
with
their
attachments shall overlap the
entrance frame and sill by not
less than 51 mm in the closed
position.
Rails and their supports shall withstand the
forces specified in Section 6.3.9.1 (d) (6).
Where truckable sills are provided as
specified in Section 6.3.9.1 (ci) (2), the rails
shall withstand any reactions which may be
(g) The clearance between a panel
and the frame lintel, between a
79
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
panel and the sill, and between
related panels of multi-speed
entrances, shall not exceed 25
mm.
2.
Exception: For emergency use see
Sec. 6.C.10.3.
(h) The entrance assembly shall be
capable of withstanding a force
of 113 kg applied on the landing
side at right angles to, and
approximately at the center of
the panel. This force shall be
distributed over an area of
approximately 102 mm by 102
There shall be no
mm.
permanent
appreciable
displacement of deformation of
any parts of the entrance
assembly resulting from this
test.
(i)
b.
The device shall be designed to
prevent unlocking the door with
common tools.
4.
The unlocking device keyway shall
be located at a height no greater
than 2 110 mm above floor.
Emergency
for
Hoistway
to
5.15 Access
Purposes. Hoistway door unlocking devices
confirming to Section 6.C.10.2 (a) and (c) may
be provided for all hoistway doors subject to the
following:
Means shalt be provided to
close the opening between the
of pass-type
panel
upper
entrances and the entrance
frame lintel. The sum of the
clearance between the panel,
the device used to close the
opening, and the entrance lintel
shalt not exceed 25 mm. The
device used shall be made of a
material having a melting point
of not less than 982°C.
a.
The elevator shall have hoistway doors
which are unlocked when closed with the
car at the floor or locked but can be opened
from the landing by means effective only
when car is in the landing zone.
1.
The operating means for unlocking
the doors shall be kept on the
premises by the person responsible
for the maintenance and operation
of the elevators in a location readily
accessible to qualified persons in
case of an emergency but where
they are not accessible to the
general public.
(b):
6.C.10.3
Sec.
Exception:
Emergency hoistway doors which
shall be provided with unlocking
devices confirming the requirements
of the Section 6.C.9.
Device.
Unlocking
Door
Hoistway
Elevators having hoistway doors which are
unlocked when closed with car at landing,
shall be provided with hoistway door
unlocking devices or devices confirming to
the requirements of Section 6.C.10.2.
Note: (Sec. 6.C.10.3): For diagram
representation, see Appendix E.
Location and Design of Hoistway Door
Hoistway door
Unlocking Devices.
unlocking devices shall conform to the
following:
1.
3.
Note: For diagram representation,
see Appendix E.
Inspection,
for
Hoistway
to
5.14 Access
Maintenance or Repairs. Access means
conforming to the requirements of Section
6.C.10.1 shall be provided at one upper landing
to permit access to top of car, and at the lowest
landing if this landing is the normal point of
access to the pit.
a.
The device shall be installed only at
the access landings.
Section 6.0 Machinery and Equipment for
Electric Elevators
6.1
The device shall unlock and permit
the opening of the hoistway door
from the access landing irrespective
of the position of the car.
80
Car and Counterweight Guide Rails, Guide
Rail Supports and Fastenings.
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
a.
b.
Guide Rails Required. Passenger and
freight elevators shall be provided with car
and counterweight guide rails.
2.
Material. Guide rails, guide-rail brackets, rail
clips, fish plates, and their fastenings shall
be of steel or other metals conforming to the
requirements of this section.
d.
Exception: Where steel may present an
accident hazard, as in chemical or explosive
plants, guide rails may be of selected wood
or other suitable non metallic materials
provided the rated speed of the car does not
exceed 0.76 meter per second.
1.
(a) Rails, brackets, fish plates, and
rail clips shall be made of openhearth steel or its equivalent
having a tensile strength of not
less than 379 MPa and having
an elongation of not less than
22% in a length of 51 mm.
(b) Bolts
shall
ANSI/ASTM
equivalent.
conform
A307,
to
or
(c) Rivets
shall
ANSI/ASTM
equivalent.
conform
A502,
to
or
Maximum Load on Rails in Relation to
the Bracket Spacing
1.
Requirements for Steel, Where
Used:
They shall have a sectional area
sufficient
withstand
the
to
compressive forces resulting from
the application of the car or
counterweight safety device.
With Single Car or Counterweight
Safety. Where a single car or
counterweight safety is used, the
maximum suspended weight of the
counterweight, including the weight
of any compensating ropes or
chains and of any traveling cables
suspended therefrom, per pair of
guide rails, shall not exceed the
maximum specified in Fig. 6.D.1.4
(a) (1) for the size of the rail and the
bracket spacing used.
Exceptions: The bracket spacing
may exceed the values specified in
Fig. 6.D.1.4 (a) (1) for a given
weight of car plus its rated load or
for a counterweight with safety, per
pair of guide rails, provided:
(a) the guide rail is reinforced; or
2.
c.
(b) rail of larger size is used;
in Sec. 6.D.1.4, exceptions (1) and
(2) above, the moment of inertia of a
single reinforced rail or of a single
larger size T-section about the axis
(x-x) parallel to the base of the rail
shall not be less than that required
by Fig. 6.D.1.4 (a) (2) for the given
weight of car plus load, or the
counterweight with safety device, at
the bracket spacing used.
Requirements for Metals other
than Steel. Metals other than steel
may be used provided the factor of
safety is not less than, and the
deflections are not more than, the
values specified in this Section, and
provided that the cast iron is not
used.
Rail Section. Guide rails shall be T-section,
conforming to the nominal weights and
dimensions shown in Fig. 6.D.1.3 and Table
6.D.1.3.
Nominal
Weight
Kg/rn
11.91
16.37
17.86
22.32
27.53
33.48
44.65
Exception: Other approved shapes may be
used subject to the following requirements:
1.
They shall have a section modulus
and moment of inertia equal to or
greater than that of the section
shown in Fig. 6.D.1.3 for a given
loading condition.
81
Table 6.D.1.3
Guide Rail Dimension
Nominal Dimensions, in.
D
A
B
C
E
-
61.91
88.90
88.90
88.90
107.95
101.60
127.00
88.90
114.3
127.0
127.0
139.7
139.7
139.7
15.88
15.88
15.88
15.88
19.05
28.58
38.10
31.75
38.10
44.45
50.01
50.01
50.80
57.15
7.94
7.94
7.94
12.70
12.7
14.29
17.46
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
2.
3.
Car or
With Two (Duplex)
Counterweight Safeties. Where
the car or counterweight is provided
with two safety devices, the loads
specified in Fig. 6.D.1.4 (a) (1) may
be increased by the factors
specified in Table 6.D.1.4 (b).
Counterweight With No Safety.
Guide rails for counterweights not
provided with a safety device shall
be fastened to the building structure
at intervals not more than 4 880
mm, and the weight of the
counterweight for each size of guide
rail shall not exceed that specified in
Table 6.D.1.4 (c)(1).
a.
Type and Strength of Rail Joints. Metal
guide rail sections shall be joined together
as specified in 6.D.1.4 (b).
b.
Design and Construction of Rail Joints.
The joints of metal guide rails shall conform
to the following requirements:
Table 6.D.1.4 (b)
Load Multiplying Factor for Duplex Safeties
Multiply Load in
Fig. 6.4.1.4 (a) (1) by
2.00
1.83
1.67
1.50
Vertical Distance bet.
Safeties,
18 or more ft.
15ft
12ft
9ft
brackets,
Intermediate
tie
approximately equally spaced, shall
be provided between the guide rails
at intervals as specified in Table
6.D.1.4 (c) (2).
Table 6.D.1.4 (c) (I)
Guide Rails for Counterweight Without Safeties
Intermediate tie brackets are not
required to be fastened to the
building structure.
Exception: The bracket spacing
specified may be increased by an
amount determined by Figs. 6.D.1.4
(a) (1) and 6.D.1.4 (a) (2), subject to
the following requirements:
(a) Where guide rails are reinforced
or a larger rail section is used
having a moment of inertia
about an axis parallel to the
base [axis x-x Fig. 6.D.1.4 (a)
(2)], at least equal to that of the
rail sections shown in Table
6.D.1.3, based on the weight of
the counterweight; and
Weight of
Counterweight,
Nominal Weight
Of guide rail,
kg
6,804.0
12,247.2
13,154.4
18,144.0
25,401.6
36,288.0
kg/rn
11.91
16.37
17.86
22.32
27.53
33.48
Max. Bracket
Spacing without
Reinforcement,
rn
4.88
4.88
4.88
4.88
4.88
4.88
Table 6.0.1.4 (c) (2)
Intermediate Tie Brackets
Nominal Distance Bet.
Fastening to Building
Structure, cm
0to366
366 to 427
427 to 488
intermediate
(b) Where
tie
brackets, approximately equally
spaced, are provided between
the guide rails at intervals of not
over 2 130 mm.
6.2
Rail Joints and Fish plates
6.2.1
NOTE:
m
kg
kg/rn
Brackets, Fastenings, and Supports. The
guide rail brackets, their fastenings and
supports, such as building beams and walls,
shall be capable of resisting the horizontal
forces imposed by the class of loading with a
total deflection at the point of support not in
excess of 3 200 mm.
=
=
=
0
1
2
ftx0.305
lbxO.454
Ib/ftxl.49
1.
82
No. of Intermediate
Tie Brackets
The ends of the rails shall be
accurately machined with a tongue
and matching groove centrally
located in the web.
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
2.
3.
The backs of the rail flanges shall
be accurately machined, in relation
to the rail guiding surfaces, to a
uniform distance front to back of the
rails to form a flat surface for the
fish plates.
Table 6.4.1.9
Minimum Size of Rail-Fastening Bolts
Nominal Weight kg/m
11.91
16.37
17.86
22.32
27.53
33.48
44.65
The ends of each rail shall be bolted
to the fishplates with not fewer than
four bolts.
Table 6.D.1.6 (b)
Minimum Thickness of Fish plates, and
Minimum Diameter of Fastening Bolts
Nominal Weight
kg/m
11.91
16.37
17.86
22.32
27.53
33.48
44.65
—
Mm. Thickness
of Fish Plates,
mm
14.29
17.46
7.46
17.46
20.64
20.64
20.64
Bolts used for fastening shall be such
strength as to withstand the forces specified
in Section 6.D.1.5.
12.70
15.88
15.88
15.88
19.05
19.05
19.05
The width of the fishplates shall be
not less than the width of the back
of the rail.
5.
The thickness of the fishplates and
the diameter of the bolts for each
size of guide rail shall not be less
than specified in Table 6.D.1.4 (b).
6.
d.. Type of Fastening. Guide rail shall be
secured to their brackets by clips, welds or
bolts.
Mm. Diameter of
Bolts, mm
4.
e.
Size of Bolts for Fastenings. The size of
bolts used for fastening the guide rails or rail
clips to the brackets shall be not less than
specified in Table 6.D.1.9.
f.
Bolt Holes for Fastening. The diameter of
holes or the width of slots for fastening bolts
shall not exceed the diameter of the bolt by
more than 1.6 mm.
6.2.2
Car and Counterweight Buffers
a.
The diameter of bolt holes shall not
exceed the diameter of the bolts by
more than 1.6 mm for guide rails nor
3 200 mm for fishplates.
Spring, Oil, or Equivalent Buffers. Buffers
of the spring, oil, or equivalent type shall be
installed under cars and counterweights of
passenger and freight elevators.
Spring buffers or their equivalent may be
used where the rated speed is not in excess
of 1.02 m/s.
Exception: Joints of different design and
construction may be used subject to the
approval of the enforcing authority,
provided they are equivalent in strength
and will adequately maintain the
accuracy of the rail alignment.
c.
-
Mm. Diameter of Bolts, mm
12.70
15.88
15.88
15.88
19.05
19.05
19.05
Exception: Where type C safeties are used
(see Sec. 6.D.6.7 (a), car buffers are not
required provided solid bumpers are
installed.
Bracket Fastenings. Guide-rail brackets
shall be secured to their supporting structure
by means of bolts, rivets, or by welding.
Fastening bolts and bolt holes in brackets
and their supporting beams shall conform to
the requirements of Sections 6.D.1.8 to
6.D.1.10.
83
b.
Location. Buffers or bumpers shall be
located so as to retard the car and
counterweight without exceeding allowable
design stresses in the car frame and
counterweight frame.
c.
Construction and Requirements for Solid
Bumpers. Solid bumpers used with Type C
safeties shall be made of wood or other
suitably resilient material of sufficient
strength to withstand without failure and
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
impact of the car with rated load, or the
counterweight, descending at governor
tripping speed.
1.
Retardation. Oil buffers shall
develop an average retardation not
2 and shall
in excess of 9.81 rn/s
greater
retardation
peak
no
develop
2 having a duration
than 24.54 m/s
exceeding 1/25 sec with any load in
the car from rated load to a
minimum load of 68 kg when the
buffers are struck with an initial
speed.
2.
Factor of Safety for Oil-Buffer
Parts. The factor of safety of parts
of oil buffers, based on the yield
point for compression members and
on the ultimate strength and
elongation for other parts, at gravity
retardation with the maximum load
for which the buffer is designed,
shall be not less than the following:
The material used shall be of a type which
will resist deterioration or be so treated as to
resist deterioration.
d.
Construction and
Spring Buffers.
Requirements
for
1.
Stroke. The stroke of the buffer
spring, as marked on its marking
plate, shall be equal to or greater
than as specified in Table 6.D.2.4
(a).
2.
Marking Plate. Each spring buffer
shall have permanently attached to
it a metal plate marked in legible
and permanent manner to show its
stroke and load rating.
(a) 3 for materials having an
elongation of 20% or more in a
length of 51 mm.
Table 6.0.2.4 (a)
Minimum Spring Buffer Stroke
Rated Car Speed
cm/s
0.50 or less
0.51 to 0.75
0.76 to 1.20
(b) 3 1/2 for materials having an
elongation of from 15 to 20% in
alength of 51 mm.
Minimum Stroke
mm
38.1
63.5
101.6
(c) 4 for materials having an
elongation of from 10 to 15% in
alength of 51 mm.
Table 6.4.2.5
Minimum Oil Buffer Strokes
Rated Speed
rn/s
1.02
1.14
1.27
1.52
1.78
2.03
2.29
2.54
3.05
3.56
4.06
4.57
5.08
e.
-
155% of
Rated Speed
m/s
1.17
1.31
1.46
1.75
2.04
2.34
2.64
2.92
3.51
4.09
4.67
5.26
5.84
(d) 5 for materials having an
elongation of less than 10% in a
length of 51 mm except that
cast iron shall have a factor of
safety of 10.
*Minimum
Stroke
mm
69.85
88.90
107.95
158.75
209.55
279.40
349.25
431.80
628.65
857.25
1098.55
1409.70
1739.90
3.
Means for Determining Oil Level.
Oil buffers shall be provided with
means for determining that the oil
level is within the maximum and
Glass
minimum allowable limits.
sight gages shall not be used.
4.
Approval of Oil Buffers. Oil buffers
shall be approved by the enforcing
authority subject to the following:
(a) The buffer shall be approved on
the basis of the engineering
tests; made by a qualified
testing laboratory or by the
manufacturer and witnessed by
such
of
representative
a
laboratory.
testing
qualified
Construction and Requirements for Oil
Buffers:
84
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
Tests shaH be made on a buffer
of each type or design to be
approved
and
having
the
following oil porting:
(1)
For car oil buffers, the total
weight of the car as marked
on the car crosshead data
plate plus 68 kg.
(b) The porting having the range of
maximum loads for which the
buffer is designed.
(2)
For
counterweight
oil
buffers, the weight of the
counterweight used.
(c) The porting having the range of
minimum loads for which the
buffer is designed.
(b) The maximum load rating shall
be not less than:
(1) For car oil buffers, the total
weight of the car as marked
on the cross head data
plate plus the rated load;
The firm or person installing the
buffer shall submit to the
enforcing authority an authentic
copy of the test certificate.
5.
6.
(2) For
counterweight
oil
buffers, the weight of the
counterweight used.
Upon receipt of an authentic copy of
the test certificate stating that the
buffer tested has met the specified
test requirements, the enforcing
authority shall approve the use of
such buffers. Oil buffers tested in
accordance
with
the
test
requirements of prior editions of this
Code shall be acceptable without
being re-tested, on submittal by the
person or firm installing the buffers
of the test certificate stating that the
buffer, when tested, met the
specified test requirements of that
edition of the Code. The approval
shall include buffers of the same
type or design having a greater or
shorter stroke, up to a maximum of
2 130 mm and having oil porting for
any load range within the maximum
and minimum loads for which the
buffer has been tested, provided
that the installer certifies on the
plans and specifications filed with
the enforcing authority that the
buffer as installed will conform to
the requirements of Section 6.D.2.5
(a).
7.
Buffer Marking
Plate.
Every
installed oil buffer shall have
permanently attached thereto a
metal
plate,
marked
by the
manufacturer in a legible and
permanent manner, indicating:
(a) the maximum and minimum
loads and the maximum striking
speeds for which the buffer may
be used in conformity with this
section;
(b) the
permissible
range
in
viscosity of the buffer oil to be
used, stated in Saybolt Seconds
Universal at 37.8°C;
(c) the viscosity index number of
the oil to be used;
(d) the pour point in degrees
Centigrade of the oil to be used.
6.2.3 Counterweights
Load Ratings of Oil Buffers. The
minimum and maximum load ratings
of car and counterweight oil buffers,
as indicated on the buffer marking
plate, shall conform to the following:
a.
General
Requirements
Counterweights.
1.
(a) The minimum load rating shall
be not greater than:
85
of
Frames. Weight sections of a
counterweight shall be mounted in
structural or formed metal frames so
designed as to retain them securely
in place [See Sec. 6.D.3.2 (e)].
CHAPTER 6
2.
-
ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
When compensating ropes are used with a
tension sheave, one end of each rope shall
be provided with a shackle rod, or other
means which provide for individual
adjustment or rope length.
Tie Rods. At least two tie rods shall
be provided which shall pass
through all weight sections. Tie rods
shall be provided with lock nut and
cotter pins at each end.
3.
6.2.4 Design
Rods.
a.
Guiding Members. Counterweight
frames shall be guided on each
guide rail by upper and lower
guiding members attached to the
frame.
Requirements
for
Frames
and
Material. Frames and rods shall be made of
steel or other metals, provided that where
steels of greater strength than those
specified, or where metals other than steel
are used, the factor of safety used in the
design shall conform to the requirements of
Section 6.D.3.2 (c).
b.
Factor of Safety. The frame members and
their connections shall be designed with a
factor of safety of not less than 5 with the
elevator at rest and the counter-weight at
the top of its travel.
c.
Sheaves. Where a hoisting
sheaves are mounted in the
requirements of Sec. 6.D.4.9
(see also Sec. 6.D.9.2 and
requirements for sheaves).
d.
Suspension-Rope Hitch or Shapes.
Where counterweights are suspended by
ropes attached directly to the frames by
means of rope fastenings, the rope
attachments shall conform to Section
6.D.4. 10.
sheave or
frame, the
shall apply
6.D.9.3 for
e.
Securing of Weights in Fames. Filler
weight of counterweight shall be made of
cast iron in a slab form where it should be
tied rigidly to the frame by tie-rods.
f.
Rope
or
Chain
Compensating
Fastenings. Compensating chains or ropes
shall be fastened to the counterweight frame
directly or to a bracket fastened to the frame
and shall not be fastened to the tie rods.
Car Frames and Platforms
6.2.4
Exception: Tie rods are not required
where other means are provided to
retain weight sections in place if
they become broken.
a.
Car Frames Required. Every elevator shall
have a car frame (see Section 6.B
definitions).
b.
Guiding Members. Car frames shall be
guided on each guide rail by upper and
lower guiding members attached to the
frame.
c.
Design of Car Frames and Guiding
Members. The frame and its guiding
members shall be designed to withstand the
forces resulting under the loading conditions
for which the elevator is designed and
installed (see Section 6.D.8).
d.
Underslung or Sub-Post Frames. The
vertical distance between the center lines of
the top and bottom guide shoes of an
elevator car having a sub-post car frame or
having an underslung car frame located
entirely below the car platform, shall be not
less than 40% of the distance between
guide rails.
e.
Car Platforms. Every elevator car shall
have a platform consisting of a non
perforated floor attached to a platform frame
supported by the car frame, and extending
over the entire area within the car enclosure.
The platform frame members and the floor
shall be designed to withstand the forces
developed under the loading conditions for
which the elevator is designed and installed.
Exception: Laminated platforms may be used for
passenger elevators having a rated load of 2270
kg or less. The deflection at any point of a
laminated platform when uniformly loaded to
rated capacity, shall not exceed 1/960 of the
span. The stresses in the steel facing shall not
exceed 1/5 of its ultimate strength and the
stresses in the plywood core shall not exceed
60% of the allowable stresses in Section 3.14 of
the American Plywood Association Plywood
Design Specification. Platform frames are not
required where laminated platforms are
provided.
86
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
f. Materials for Car Frames and Platform
Frames. Materials used in the construction
of car frames and platforms shall conform to
the following:
1.
g.
adequately reinforced and braced to the car
platform and conforming to the following:
Car frames and outside members of
platform frames shall be made of
steel or other metals.
2.
Platform
stringers
freight
of
elevators designed for Class B or C
loading shall be of steel or other
metals.
3.
Platform
elevators
designed
be made
of wood.
1.
It shall extend not less than the full
width of the widest hoistway-door
opening.
2.
It shall have a straight vertical face,
extending below the floor surface of
the platform, of not less than the
depth of the leveling or truck zone,
plus 76 mm.
3.
The lower portion of the guard shall
be bent back at an angle of not less
than 60° nor more than 75° from the
horizontal.
4.
The guard plate shall be securely
braced and fastened in place to
withstand a constant force of not
less than 68 kg applied at right
angles to and at any position on its
face without deflecting more than
6.3 mm, and without permanent
deformation.
stringers of passenger
and of freight elevators
for Class A loading shall
of steel or other metals, or
Cast iron shall not be used for any part
subject to tension, torsion or bending.
1.
Guiding supports
2.
Guide shoes
3.
Compensating rope anchorages
Where the car entrance on the
truck-loading side is provided with a
collapsible-type gate and the height
of the hoistway door opening is
greater than the distance from the
car floor to the car top, a head
guard extending the full width of the
door opening shall be provided on
the car to close the space between
the car top and the soffit of the
hoistway-door opening when the car
platform is level with the floor at the
truck-loading landing entrance.
h. Protection of Platforms Against Fire. The
underside of wood platforms, the exposed
surfaces of wood platform stringers, and
edges of laminated platforms shall be
protected against fire by one of the following
methods:
1.
Covering with sheet steel of at least
0.4166mm thickness or with equally
fire-retardant material.
2.
Painting with an approved fireretardant paint having a flame
spread rating of not over 50, applied
in accordance with the instructions
of the manufacturer. Such ratings
shall be based on the test
procedure specified in ANS l/ASTM
E84.
Car Frames with Crosshead Sheaves.
Where a hoisting-rope sheave is mounted
on the car frame, the construction shall
conform to the following:
1.
Platform Guards (Aprons). The entrance
side of the platform of passenger and freight
elevators equipped with leveling devices or
truck-zoning devices shall be provided with
smooth metal guard plates of not less than
1.519 mm thick steel, or material of
equivalent
strength
and
stiffness,
87
Where multiple sheaves mounted
on separate sheave shafts are
used, provision shall be made to
take
the
compressive forces,
developed by tension in the hoisting
ropes between the sheaves, on a
strut or struts between the sheave
shaft supports, or by providing
additional compressive strength in
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
operation of the elevator by the
normal operating device unless the
hinged sill is within 51 mm of its fully
retracted position, provided that
when in this position, the sill shall
not reduce the clearance specified
in Section 6.C.8.4.
the car frame or car-frame members
supporting the sheave shafts.
2.
3.
Where the sheave shaft extends
through the web of a car-frame
member, the reduction in area of the
member shall not reduce the
strength of the member below that
necessary,
Where
required.
reinforcing plates shall be welded or
riveted to the members to provide
the required strength.
Where the sheave is attached to the
car crosshead by means of a single
threaded rod or specially designed
member or members in tension, the
following requirements shall be
conformed to:
The strength of the sills shall
conform to the requirements of
Section 6.C.9.6.
Enclosure Required. Elevators shall be
equipped with a car enclosure.
b.
Securing of Enclosures. The enclosure
shall be securely fastened to the car
platform and so supported that it cannot
loosen or become displaced in ordinary
service or on the application of the car
safety or on buffer engagement.
The car enclosure shall be so constructed
be
cannot
portions
removable
that
dismantled from within the car.
c.
or
Plates
Hitch
Suspension-Rope
by
suspended
Shapes. Where car are
hoisting ropes attached to the car frame by
means of rope shackles, the shackles shall
be attached to steel hitch plates or to
structural or formed steel shapes. Such
plates or shapes shall be secured to the
underside or to the webs of the car-frame
member with bolts, rivets or welds so
located that the tensions in the hoisting
ropes will not develop direct tension in the
bolts or rivets.
Platform Side Braces. Where side bracing
and similar members are attached to car
frame uprights the reduction in area of the
upright shall not reduce the strength of the
upright below that required by this Section.
m. Hinged Platform Sills. Hinged platform sills
shall conform to the following requirements:
1.
3.
a.
(b) The means for fastening the
single threaded rod, member or
members to the car frame shall
conform to Section 6.D.4.10.
k.
The elevator may be operated by
the leveling device in the leveling
zone with the sill in any position.
Car Enclosures, Car Doors and Gates, and
Car Illumination
6.2.6
(a) The single rod, member or
members shall have a factor of
safety 50% higher than the
factor of safety required for the
suspension wire ropes, but in no
case shall have a factor of
safety of less than 15.
2.
d.
They shall be provided with electric
prevent
will
which
contacts
88
Deflection of Enclosure Walls. The
enclosure walls shall be of such strength
and so designed and supported that when
subjected to a force of 35 kg applied
horizontally at any point on the walls of the
enclosure, the deflection will not reduce the
running clearance below the minimum
specified in Sec. 6.3.8, or not to exceed 25
mm.
1.
used
be
elevator shall
The
or
passengers
exclusively for
one
any
at
freight
for
exclusively
time.
2.
Each compartment shall conform to
the requirements of this Section that
a trap door in the floor of the upper
compartment shall provide access
to the top emergency exit for the
lower compartment.
Top Emergency Exits. An emergency exit
with a cover shall be provided in the top of
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
all elevator cars and shall conform to the
following requirements:
1.
The exit opening shall have an area
of not less than 0.258 m
, and shall
2
measure not less than 406 mm on
any side.
2.
The exit shall be so located as to
provide
clear
passageway
a
unobstructed by fixed elevator
equipment located in or on top of
the car.
3.
The exit cover shall open outward
and shall be hinged or otherwise
attached to the car top and so
arranged that the cover can be
opened from the top of the car only.
4.
passengers in case the glass panels
break or are dislodged.
4.
c.
Equipment
Prohibited
Inside
Cars.
Apparatus or equipment other than that
used in connection with the operation of the
elevator, shall not be installed inside any
elevator car.
Exceptions:
The emergency exit cover, when
opened, shall automatically actuate
a switch to turn-off the power so that
the elevator shall be non-operable
even with the restoration of power.
6.2.8
Exception: [Sec. 6.D.5.4 (c)]: The
exit cover of a lower deck of a multideck elevator can be opened from
either compartment.
1.
Railroad and conveyor tracks in
freight elevators
2.
Lighting, heating, ventilating, and
air-conditioning
equipment
[see
Sec. 6.C.3.1 (a)].
Illumination
Fixtures.
a.
Car-Enclosure Tops. Tops of car enclosures
shall be so designed and installed as to be
capable of sustaining a load of 136 kg on any
square area 610 mm on a side and45 kg
applied at any point. Simultaneous application
of these loads is not required.
of
Cars
and
Lighting
Illumination and Outlets Required. Cars
shall be provided with an electric light or
lights conforming to the following:
1.
6.2.7
Be so mounted in the structure, that
the structure including the glass in
place shall withstand the required
elevator tests without damage.
Not less than two lamps shall be
provided.
2. The minimum illumination at the car
threshold, with the door closed,
shall not be less than:
(a) For passenger elevators: 54 lux
a.
b.
Equipment Prohibited on Top of Cars. A
working plafform or equipment which is not
required for the operation of the elevator or
its appliances, except where specifically
provided herein, shall not be located above
the top of an elevator car.
(b) For freight elevators: 27 lux
3.
Glass in Elevator Cars. Glass may be used
in elevator cars. Glass exceeding 0.093 m
2
in area shall:
1.
Be laminated;
2.
Meet the requirements for laminated
glass of ANSI Z97.1 except as to
transparency;
3.
Be installed and guarded so as to
provide adequate protection for
Passenger elevators shall
be
provided with an emergency lighting
power source on each elevator
conforming to the following:
(a) The emergency system shall
provide
some
general
illumination in the car. The
intensity of illumination 1220
mm above the car floor and
approximately 305 mm in front
of the car operating device shall
be not less than 22 lux. Lights
shall be automatically turned on
in all elevators in service
immediately after normal car
89
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
shall be located within or below the lower
members of the car frame (safety plank).
lighting power fails. The power
system shall be capable of
maintaining the above light
intensity for a period of at least
4 hours.
All car safeties shall be mounted on a single
car frame and shall operate only on one pair
of guide rails between which the frame is
located.
(b) Not less than two lamps of
approximately equal wattage
shall be used.
4.
b.
b.
Duplex Safeties. Where duplex (two)
safeties are provided, the lower safety
device shall be capable of developing not
less than one-half of the force required to
stop the entire car with rated load (see Sec.
6.4.8.8). Duplex safety devices shall be
arranged so as to function approximately
simultaneously. Type A or Type C safety
devices (see Sec. 6.4.6.4) shall not be used
in multiple (duplex).
c.
Counterweight Safeties. Counterweight
safeties shall conform to the requirements
for car safeties.
Each elevator shall be provided with
an electric light and convenience
outlet fixture on the car top.
Passenger-Car Lighting Devices. Glass
used for lighting fixtures shall conform to the
requirements of Section 6.D.5.7.
Suspended glass used in lighting fixtures
shall be supported by a metal frame secured
at not less than three points. Fastening
devices shall not be removable from the
fixture. Glass shall not be drilled for
attachment. Light through supporting wiring
raceways and other auxiliary lighting
equipment, where used, shall be of metal
except where lined with non combustible
materials.
Exceptions:
1.
Where otherwise specified in Sec.
6.4.6.
2.
For rated speeds of not over 0.76
m/s, counterweight safeties may be
operated as a result of the breaking
or slackening of the suspension
ropes and may be of the inertia or
types without
other approved
governors (see Sec. 6.4.6.6 and
6.4.7).
3.
A switch operated by the safety
mechanism is not required for
counterweight safeties (se Sec.
6.D.6.6).
Lighting arrangements using slow-burning
combustible materials for diffusing and
illumination purposes shall be permitted
providing such combustible materials do not
come in contact with lighting equipment.
c.
Protection of Light Bulbs and Tubes.
Light bulbs and tubes shall be:
1.
2.
Installed and guarded so as to
provide adequate protection incase
the bulb or tube in the structure,
shall withstand the required elevator
tests without damage.
d.
So mounted in the structure, that
the structure including the bulb or
tube in the structure, shall withstand
the required elevator tests without
damage.
1.
Car and Counterweight Safeties.
6.2.9
a.
Identification and Classification of Types
of Safeties. Car safety devices (safeties)
are identified and classified on the basis of
perlormance characteristics after the safety
begins to apply pressure on the guide rails.
On this basis, there are three types of
safeties:
The car of every elevator suspended by wire
ropes shall be provided with one or more car
safety devices of one of the types identified
The safeties shall be
in Sec. 6.4.6.4.
attached to the car frame, and one safety
90
Type A Safeties. Safeties which
increasing
rapidly
a
develop
pressure on the guide rails during
the stopping interval, the stopping
distance being very short due to the
inherent design of the safety. The
operating force is derived entirely
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALAT.ORS AND MOVING WALKS
from the mass and the motion of the
car or the counterweight being
stopped. These safeties apply
pressure on the guide rails through
eccentrics, rollers or similar devices,
without
any
flexible
medium
purposely introduced to limit the
retarding force and increase the
stopping distance.
2.
Type B Safeties. Safeties which
apply limited pressure on the guide
rails during the stopping interval,
and
which
provide
stopping
distances that are related to the
mass being stopped and the speed
at which application of the safety is
initiated.
Retarding; forces are
reasonably uniform after the safety
is fully applied. Continuous tension
in the governor rope may or may not
be required to operate the safety
during the entire stopping interval.
3.
Type C Safeties (type A with Oil
Buffers).
Safeties which develop
retarding
forces
during
the
compression stroke of one or more
oil buffers interposed between the
lower members of the car frame and
a 9overnor-operated type A auxiliary
safety plank applied on the guide
rails.
The stopping distance is
equal to the effective stroke of the
buffers.
shall conform to the requirements of
Section 6.D.7.5.
g.
Type A (Instantaneous) Safeties. Type A
safeties may be used on elevators having a
rated speed of not more than 0.76 m/s.
When over-speeding occurs, with the
hoisting rope intact, such safeties shall be
actuated by the governor.
On the parting of the hoisting ropes (free
fall), type A governor operated safeties shall
apply without appreciable delay, and their
application shall be independent of the
speed action of the governor and of the
location of the break in the hoisting ropes
(inertia
application),
and
may
be
accomplished by the use of a governor and
governor rigging having a sufficiently high
value of inertia to apply the safety on free
fall independently of the speed action of the
governor.
1.
e.
Safeties to Stop Ascending Cars or
Counterweight Prohibited. Safeties shall
not stop an ascending car or counterweight.
f.
Governor-Actuated Safeties and CarSafety Mechanism Switches Required.
1.
(a) The rated speed shall be not
more than 2.54 m/s.
(b) The oil buffers shall conform to
aB requirements specified in
Section 6.D.2 for oil buffers,
except that the stroke shall be
based on governor tripping
speed and on an average
retardation not exceeding 9.81
.
2
rn/s
(c) After the buffer stroke, as
defined in Sec. 6.D.6.7 (2) has
been completed, provision shall
be made for an additional travel
of the plunger or piston of not
less thanl0% of the buffer
stroke to prevent excessive
impact on the buffer parts and
the auxiliary safety plank.
Car safeties, and counterweight
safeties, where provided, shall be
actuated
by
separate
speed
governors.
Exception: Speed governor are not
required for the operation of
counterweight safeties of elevators
having a rated speed of not more
than 0.76 m/s.
2.
Type
C
(Combination
Instantaneous and Oil Buffer
Safety). Type C safeties may be
used subject to the following
requirements:
(d) Where the distance between
guide rails exceeds 2 440 mm,
the safety shall be provided with
two oil buffers of substantially
identical calibration, and the
buffers shall be so located as to
Every car safety shall be provided
with a switch, operated by the car
safety mechanism.
This switch
91
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
develop minimum stresses in
the auxiliary safety plant during
safety operation.
a.
Routine The examination and operation of
equipment at specified intervals by an
inspector to check for compliance with the
applicable Code Requirements.
b.
Periodic Routine inspection and tests plus
and
examination
detailed
additional
operation of equipment at specified intervals
witnessed by an inspector to check for
compliance with the applicable Code
Requirements.
c.
Acceptance The initial inspection and test
for a new or altered equipment to check for
compliance with the applicable Code
Requirements.
Buffers shall be located in line
with and symmetrically between
the guide rails.
(e) The auxiliary safety plank shall
be so supported and guided
below the car frame that the
clearances for the safety parts
are maintained during normal
operation.
The auxiliary safety plank shall
be so designed that the
maximum stresses in the plant
shall not exceed those specified
for similar car-frame members
in Section 6.D.4.
—
—
—
Speed Governors
6.2.11
a.
Car Speed Governors
1.
(f) The rail-gripping device of the
auxiliary safety plank shall be so
arranged and connected as to
prevent the plank from being out
of level more than 13 mm in the
length of the plank when the
safety is operated to stop the
car.
Exception: Speed governors are not
required for the operation of safeties
of counterweights of elevators
having a rated speed of not more
than 0.76 m/s (see Sec. 6.D.6.3 and
6.D.6.6).
(g) An electric switch shall be
provided and so arranged and
connected that the elevator
cannot be operated by means of
the normal operating device if
any buffer is compressed more
than 10% of its stroke.
2.
b.
(h) Means shall be provided to
the
of
operation
prevent
elevator by means of the normal
operating device if the oil level
in any buffer is below the
minimum allowable Idvel.
h.
Car safeties, and counterweight
safeties where furnished shall be
actuated by separate governors.
Compensating Rope Tie-Down.
For rated speeds greater than 3.56
m/s, a device shall be provided to
tie the car and counterweight
together to limit the jump of the car
counterweight as a result of buffer
engagement or application of car or
counterweight safety.
The governor shall be located
where it cannot be struck by the car
or the counterweight in case of over
travel, and where there is adequate
space for full movement of governor
parts.
Car Speed Governors. Speed governors
for car safeties shall be set to trip at car
speeds as follows:
1.
At not less than 115% of the rated
speed.
2.
for
speeds
tripping
Maximum
intermediate rated speeds shall be
determined from Fig. 6.D.7.2. for
rated speeds exceeding 7.62 m/s,
the maximum tripping speeds shall
not exceed 120% of the rated
speed.
c. Counterweight Speed Governors. Speed
for
provided
where
governors,
counterweight safeties, shall be set to trip at
6.2.10 Inspection and Tests
92
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
an over-speed greater than that at which the
car speed governor is set to trip, but not
more than 10% higher.
d.
Sealing
and
Painting
of
Speed Governor Over-Speed and Car
Safety-Mechanism Switches
1.
Replacement of Existing Governor
Ropes. Replacement of governor ropes
shall be of the same size, material and
construction as the rope originally furnished
by the elevator manufacturer, except that a
rope of the same size but of either different
material or construction may be employed
and a test is made of the car Or
counterweight safety and speed governor
with a new rope to demonstrate that the
safety will function.
c.
Splicing Governor Ropes. Governor ropes
shall not be lengthened or repaired by
splicing.
d.
Governor Rope Tag. A metal data tag shall
be securely attached to the governor rope
fastening.
This data tag shall bear the
following wire rope data:
Speed
Governors. Speed governors shall have
their means of speed adjustment sealed
after test. If speed governors are painted
after sealing, all bearing and rubbing
surfaces shall be kept free or freed of paint
and a hand test made to determine that all
parts operate freely as intended. Seals shall
be of a type which will prevent readjustment
of the governor tripping speed without
breaking the seal.
e.
b.
Where Required. A switch shall be
provided on the speed governor and
operated by the over-speed action
of the governor when used with type
B and C car safeties of elevators
having a rated speed exceeding
0.76 m/s. A switch shall be provided
on the speed governor when used
with a counterweight safety for any
car speed.
For static control, an over-speed
switch shall be provided regardless
of rated speed and shall operate in
both directions of travel.
Every car safety shall be provided
with a switch operated by the car
safety mechanism when the safety
is applied.
These switches when operated shall
remove power from the drivingmachine motor and brake before or
at the time of application of the
safety.
e.
6.2.12 Governor Ropes
a.
Material and Factor of Safety. Governor
ropes shall be of iron, steel, monel metal,
phosphor bronze, or stainless steel. They
shall be of regular-lay construction, and not
less than 9.5 mm in dia.
Tiller-rope
construction shall not be used. The factor of
safety of governor ropes shall be not less
than 5.
93
1.
The diameter in mm.
2.
The manufacturer’s rated breaking
strength.
3.
The grade of material used.
4.
The month and year the rope was
installed.
5.
Whether
formed.
6.
Construction classification.
7.
Name of the person or firm who
installed the rope.
8.
Name of the manufacturer of the
rope. A new tag shall be installed at
each rope renewal.
non-preformed
or
pre
Speed Governor Marking Plate. A metal
plate shall be securely attached to each
speed governor and shall be marked in a
legible and permanent manner with letters
and figures not less than 6.3 mm in height
indicating the following:
1.
The speed in meter per minute at
which the governor is set and
sealed to trip the governor-rope-grip
jaws.
2.
The size, material and construction
of the governor rope on which the
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
W
where
governor jaws were designed to
operate.
A
6.2.13 Capacity and Loading
Exception:
W
6.3
Minimum
Elevators
Rated
All concrete or steel building with more than
three stories shall be advised to install
passenger elevators.
b.
For determining number of elevators the
following shall be used as basis:
1.
There shall be one elevator per 220
persons occupying building other
than first floor.
2.
2 of floor area is
By floor area, 9.3 m
average density of occupancy per
person.
3.
Floor area divided by 9.3 equal
number of persons.
d.
+
611.36A—621.4
Inside Net
Inside Net
Rated
Platform
Platform
Load, kg
2
Area, m
2
Area, m
4.65
2268.00
0.65
226.80
5.36
2721.60
0.77
272.16
6.07
3175.20
0.89
317.52
6.77
3628.80
1.23
453.60
7.48
4082.40
1.45
544.32
8.18
4536.00
1.76
680.40
9.57
5443.20
2.05
816.48
1 1.62
6804.00
2.25
907.20
13.65
8164.80
2.70
113.40
14.98
9072.00
3.13
1360.80
18.25
11340.00
3.53
1587.60
21.46
13608.00
3.92
1814.40
4.29
2041.20
*
To allow for variations in cab designs, an increase in
the maximum inside net platform are not exceeding
5%, shall be permitted for the various rated loads.
e.
Use of Partitions for Reducing Inside Net
Platform Area. Where partitions are
installed in elevator cars for the purpose of
restricting the platform net area for
passenger use, they shall be permanently
bolted, riveted or welded in place. Gates,
doors or handrails shall not be used for this
purpose. Partitions shall be so installed as
to provide for approximately symmetrical
loading.
f.
Carrying of Freight on Passenger
Elevators. When freight is to be carried on
the following
passenger elevator,
a
to:
shall
be
conformed
requirements
For determining capacities of elevators the
following shall be used as basis for elevator
or elevators capacities. This is on the basis
of carrying within 5 minutes the following
percentage of building occupants as follows:
10%
1.
For apartments 8
2.
Forofficesl0—13%
—
For dept. stores 13
—
15%
The following formulas shall be used for
determining the maximum rated load of
passenger elevators:
1.
2
2.458A
Table 6.D.8.1
4. ‘Number of person divided by 220 is
number of elevators.
3.
=
Rated
Load, kg
a.
c.
2
area, m
Maximum* Inside Net Platform Areas
for the Various Rated Loads
Passenger
for
Load
=
max. rated load kgs.
For an elevator having an inside net
.
2
platform area of more than 4.65 m
2.
Hospital Bed Elevators: Wherein the ratio
between net area and net load shall be not
more than 0.004 square meters per kilogram.
=
For an elevator having an inside net
platform area of not more than 4.65
2
m
W
=
2
35.10 (A)
+
326.224 (A)
94
1.
The minimum rated load shall
conform to the requirements of
Section 6.4.8.1 or 6.4.8.4 whichever
is greater;
2.
The elevator shall be designed for
applicable class of freight elevator
loading.
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
g.
Minimum Load Permitted. The minimum
rated toad for freight elevators in kilograms
shall be based on the weight and class of
the load to be handled.
(b) “THIS ELEVATOR DESIGNED
FOR
MOTOR-VEHICLE
LOADING”
h.
Carrying of Passengers on Freight
Elevators. Freight elevators shall not be
permitted to carry passengers.
(c) “THIS ELEVATOR DESIGNED
FOR LOADED INDUSTRIAL
TRUCK WEIGHING
KG.
MAXIMUM”.
Exceptions:
(d) “NO SMOKING”
1.
(e) “TELEPHONE
BELOW
CASE OF EMERGENCY”
2.
Elevators not permitted to carry
employees may, in case of fire, panic or
similar emergencies, carry passengers
not greater in number than the rated
load divided by 150.
(f) “IN CASE OF FIRE, DO NOT
USE ELEVATOR”
Elevators, not accessible to the general
public, may carry employees, provided
special permission to do so is granted
by the enforcing authority, subject to the
following conditions:
(g) “CERTIFICATE TO OPERATE
ELEVATOR”
2.
In elevators not permitted to carry
passengers, the sign shall read:
“THIS IS NOT A PASSENGER
ELEVATOR,
NO
PERSONS
OTHER THAN THE OPERATOR
AND FREIGHT HANDLERS ARE
PERMITTED TO RIDE ON THIS
ELEVATOR”
3.
In elevators permitted to carry
employees
subject
to
the
requirements of Section 6.4.8.5 the
sign
shall
read:
“NO
PASSENGERS
EXCEPT
EMPLOYEES PERMITTED.”
(a) The rated load of the elevator shall
be not less than that required for a
passenger of equivalent inside net
platform area as required by Section
6.4.8.1.
(b) Hoistway entrances and car doors
or gates shall conform to the
requirements of the following rule:
(1) Hoistway entrances:
6.3.9.
Section
Such elevators may carry any
class of passengers in case of
fire,
panic,
or
similar
emergencies.
j.
Signs Required. Signs, shall be provided
inside the car and shall be located in a
conspicuous position and permanently and
securely fastened to the car enclosure
subject to the following requirements:
1.
IN
In every freight elevator, the sign
shall specify the type of loading for
which the elevator is designed and
installed, with one of the following
markings:
(a) “THIS ELEVATOR DESIGNED
FOR
GENERAL
FREIGHT
LOADING”
95
Carrying of One-Piece Loads Exceeding
the Rated Load. Passenger and freight
elevators may be used, where necessary, to
carry one-piece loads greater than their
rated load provided they are designed,
installed and operated to conform to the
following requirements:
1.
A locking device shall be provided
which will hold the car at any
landing
independently of the
hoisting ropes while the car is being
loaded or unloaded.
2.
The locking device shall be so
designed that it cannot be unlocked
unless and until the entire weight of
the car and load is suspended on
the ropes.
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
2400
2300
2200
2100
2000
1900
1800
1700
1600
E 1500
0
1400
0)
> 1300
1200
1100
0)
>
0
0 1000
900
800
700
600
500
400
300
200
100
0
200
600
1000
800
1400
1200
1600
1800
2000
Rated Car Speed,fprn
NOTE:
rn/s
400
=
fpm x 0.00508
3.
4.
landing locks when the car
operated in the up direction.
A removable wrench or other device
shall be provided to operate the
locking device.
5.
The locking device shall be so
designed that the locking bars will
be automatically withdrawn should
they come in contact with the
96
is
A special capacity plate shall be
provided inside the elevator car and
located in a conspicuous place
which shall bear the words,
“CAPACITY LIFTING ONE-PIECE
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
6.
LOADS,” in letters followed by
figures giving the special capacity in
kgs for lifting one-piece loads for
which the machine is designed.
The car frame, car platform,
sheaves, shafts, ropes and locking
device shall be designed for the
specified “Capacity Lifting OnePiece Loads,” provided that:
machine room, located near the
driving machine, to operate the
elevator. When this device is
other
operating
operative,
all
devices shall be inoperative. (see
Sec. 6.D.11.1).
11. The “Capacity Lifting One-Piece
Loads” of any passenger traction
elevator shall not exceed 1 1/3
times the rated load of the elevator.
(a) In the design of the car frame,
platform, sheaves, shafts, and
ropes, the allowable stresses
may be 20% higher than those
permitted for normal loading;
k.
(b) The factor of safety for the
locking device shall be not less
than 5.
7.
The car safeties shall be designed
to stop and hold the specified
“Capacity Lifting One-Piece Loads,”
with the ropes intact.
6.3.1
Additional Requirements for Passenger
Overload. Passenger elevators and freight
elevators permitted by Section 6.4.8.5 to
carry employees shall be designed and
installed to safely lower, stop and hold the
car with an additional load up to 25% in
excess of the rated load.
Driving Machines and Sheaves
a.
Type of Driving Machines
1.
8.
Where there is an occupied space,
or an unauthorized access under
the
hoistway,
following
the
requirements shall be conformed to:
Exceptions:
(a) Winding-drum machines may be
used for freight elevators subject to
the if:
(a) The machine shall be designed
to operate with the “Capacity
Lifting One-Piece Loads” at
slow speed; the car safety shall
be designed to stop and hold
the
this
car
with
load
independently of the hoisting
ropes;
(b) The counterweight safety, shall
be designed to stop and hold
the entire weight of the
counterweight independently of
the ropes.
9.
All driving machines shall be of the
traction type.
1.
They shall not be provided with
counterweights.
2.
The rated speed of elevator
shall not exceed 0.25 m/s.
3.
The travel of the elevator car
shall not exceed 12.2 m.
(b) Screw nachines conforming to the
require nents of Section 6.D.9.5.
For traction
machines,
where
necessary to secure adequate
traction, additional counterweight
shall be added during the period of
use with one-piece loads so that the
total over-balance is at least equal
to 45% of the “Capacity Lifting OnePiece Loads.”
b.
Material and Grooving for Sheaves and
Drums. Sheaves and drums used with
suspension and compensating ropes shall:
1.
10. A special operating device of the
car-switch or continuous-pressure
type shall be provided in the
97
Be of metal and provided with
The
finished grooves for ropes.
grooves of sheaves not used to
transmit power may be lined with
non-metallic material. The grooves
of sheaves used to transmit power
may be lined with non-metallic
material provided that in the event
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
shall be provided unless other
means are provided to limit the
down speed of the car with rated
load to not over 0.89 m/s if there is
a failure of the driving means.
the lining should fail, there will be
sufficient traction still available in
the groove to safely stop and hold
the car with 125% of the rated load.
2.
Have a pitch diameter of not less
than:
3.
(a) 40 times the diameter of the
with
used
where
rope,
suspension ropes;
(a) Belts shall be of the multiple V
belt type.
(b) 32 times the diameter of the
with
used
where
rope,
compensating ropes.
c.
(b) Two or more separate chains
shall be provided.
Factor of Safety for Driving Machines
and Sheaves. The factor of safety, based
on the ultimate strength of the material, to
be used in the design of driving machines
and in the design of sheaves used with
suspension and compensating ropes shall
be not less than:
1.
8 for steel, bronze, or for other
metals having an elongation of at
least 14% in a length of 51 mm.
2.
10 for cast iron, or for other metals
having an elongation of less than
14% in a length of5l mm.
(c) The driving means, whether
belts or chains, shall have a
factor of safety of not less than
10.
(d) The machine brake shall be so
located that failure of the driving
belt or chain will not prevent it
from performing its intended
function.
The load to be used in determining
the factor of safety shall be the
resultant of the maximum tensions
in the ropes leading from the
sheave or drum with elevator at rest
and with rated load in the car.
d.
Driving-Machine Brakes. The elevator
driving machine shall be equipped with a
friction brake applied by a spring, or by
gravity, and released electrically. The brake
shall be designed to have a capacity
sufficient to hold the car at rest with its rated
load [see also Sec. 6.D.8.8.J.
Screw Machines. Screw machines shall be
of the uncounterweighted type and shall
conform to the requirements of the section
and to the following:
1.
2.
a.
The rated speed shall not exceed
0.25 m/s.
4.
The factor of safety of the screw as
a column shall be not less than 3
based on the total weight supported
with rated load in the car.
5.
Means shall be provided to maintain
the screw in its vertical position in
case of excessive over-travel.
6.
Screws shall be of steel and nuts
shall be of bronze or other material
having an elongation of at least 14%
inalength of 51 mm.
7.
A vertical casing, closed at the
bottom, shall be provided to enclose
and protect the screw below the nut.
Terminal Stopping Devices
6.3.2
e.
Where belts or chains are used to
connect the motor to the driving
following
the
machines
requirements shall be conformed to:
Additional Requirements for Winding
Drum Machines. Final terminal stopping
devices for winding-drum machines shall
conform to the following:
1.
A car safety device conforming to
the requirements of Section 6.4.6
98
Stopping switches, located on and
operated by the driving machine,
shall not be driven by chains, ropes,
or belts.
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
2.
cause the electric power to be
removed from the elevator driving
machine motor and brake if the
hoisting ropes become slack.
Where
a
two-or
three-phase
alternating-current driving-machine
motor is used, the main-line circuit
to the driving-machine motor and
the circuit of the driving-machine
brake coil shall be directly opened
either by the contacts of the
machine stop switch or by stopping
switches mounted in the hoistway
and operated by a cam attached to
the car.
The opening of these
contacts shall occur before or
coincident with the opening of the
final-terminal stopping switch.
Exception:
Driving machines
equipped with a direct-current brake
and having a direct-current main
line control switch in the drivingmachine motor circuit controlled by
a final terminal stopping switch
located in the hositway and
operated by a cam attached to the
car.
6.3.3
2.
Motor-Generator Running Switch.
Where generator-field control is
used, means shall be provided to
prevent the application of power to
the elevator driving machine motor
and brake unless the motor
generator set connections are
properly switched for the running
condition of the elevator. It is not
required
that
electrical
the
connections between the elevator
driving machine motor and the
generator be opened in order to
remove power from the elevator
motor.
3.
Compensating-Rope
Sheave
Switch.
Compensating-rope
sheaves shall be provided with a
compensating-rope sheave switch
or switches mechanically opened by
the
compensating-rope
sheave
before the sheave reaches its upper
or lower limit of travel, to cause the
electric power to be removed from
the elevator driving machine motor
and brake.
4.
Motor Field Sensing Means.
Where direct current is applied to an
elevator armature and shunt field of
a driving machine motor, a motorfield current sensing means shall be
provided, which shall cause the
electric power to be removed from
the motor armature and brake
unless current is flowing in the shunt
field of the motor.
Operating Devices and Control Equipment
a.
b.
c.
Additional
Operating
Devices
for
Elevators Equipped to Carry One-Piece
Loads Greater than the Rated Load.
Elevators equipped to carry one-piece loads
greater than their rated load shall be
provided with an additional operating device
of the continuous-pressure type, located
near the driving machine, to operate the
elevator at a speed not exceeding 0.75 m/s
under such conditions.
The normal
operating devices shall be inoperative
during such operation. [See also Sec.
6.D.8.7 (j)].
For elevators with static control, an inner
landing zone extending not more than 76
mm above and 76 mm below the landing
shall be provided.
Exception: Static control elevators
provided with a device to detect an
over-speed condition prior to, and
independent of, the operation of the
governor over-speed switch. This
device shall cause power to be
removed from the elevator driving
machine motor armature and
machine brake.
Electrical Protective Devices. Electrical
protective devices shall be provided in
accordance with the following:
1.
Slack-Rope Switch. Winding-drum
machines shall be provided with a
slack-rope device equipped with a
slack-rope switch of the enclosed
manually reset type which shall
5. Emergency
Stop
Switch.
An
emergency stop switch shall be
provided in the car, and located in
99
CHAPTER 6
-
ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
speed switch shall be provided
when required by Sec. 6.D.7.5 (a).
or adjacent to the car operating
panel. When opened, this switch
shall cause the electric power to be
removed from the elevator drivingmachine motor and brake.
11. Final Terminal Stopping Devices.
Final terminal stopping devices,
shall be provided for every electric
elevator.
Emergency Stop Switches shall:
Speed
Terminal
12. Emergency
Limiting Devices. Where reduced
stroke oil buffers are provided,
emergency terminal speed limiting
devices shall be provided.
(a) Be of the manually operated
and closed type;
(b) Have red operating handles or
buttons;
13. Buffer Switches for Oil Buffers
used with Type C Car Safeties.
Oil level and compression switches,
conforming to the requirements of
Sec. 6.D.6.7 (a) (7) and 6.D.6.7 (a)
(8) shall be provided for all oil
buffers used with type C safeties
[See Sec. 6.D.6.4 (c)].
and
conspicuously
(c) Be
permanently marked “STOP”
and shall indicate and stop and
run positions;
opened
positively
(d) Be
mechanically and their opening
shall not be solely dependent on
springs.
6.
7.
8.
9.
or
Interlocks
14. Hoistway-Door
Hoistway-Door Electric Contacts.
or
interlocks
door
Hoistway
hoistway-door electric contacts,
shall be provided for all elevators.
Broken Rope, Tape, or Chain
Switches Used in Connection
with Machine Room NormalSwitches.
Stopping
Terminal
chain
or
tape
rope,
Broken
switches, shall be provided in
connection with normal terminal
stopping devices located in machine
rooms of traction elevators. Such
switches shall be opened by a
failure of the rope, tape or chain.
Electric
Gate
or
15. Car-Door
Contacts. Car-door or gate electric
contacts, shall be provided for all
elevators.
Stopping
Terminal
16. Normal
Devices. Normal terminal stopping
the
to
conforming
devices,
requirements of Sec. 6.D.3.2 shall
be provided for every elevator.
Stop Switch in Pit. A stop switch
conforming to the requirements of
Sec. 6.D.11 (e) shall be provided in
the put of every elevator. (See Sec.
6.C.6.5).
Door
17. Car-Side-Emergency-Exit
Contact Switches. A car-door
electric contact, shall be provided
on the car-side-emergency-exit door
of every elevator.
Stop Switch on Top of Car. A stop
the
to
conforming
switch
requirements of Sec. 6.D.11.3 (e)
shall be provided on the top of every
elevator car.
Over-Speed
18. Motor-Generator
be
shall
Means
Protection.
provided to cause the electric power
to be removed automatically from
the elevator driving-machine motor
and brake should a motor generator
set, driven by a direct current motor,
over-speed excessively.
Car-Safety Mechanism Switch. A
the
to
conforming
switch,
requirements of Sec. 6.D.6 and
6.D.7.5 (a) shall be required where
a car safety is provided.
Over-Speed
10. Speed-Governor
Switch. A speed-governor over-
19. Electric Contacts for Hinged Car
Platform Sills. Hinged car platform
100
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
sills, where provided, shall be
equipped with electric contacts
conforming to the requirements of
Section 6.D.4.12.
(b) The contactor shall be arranged
to open each time the car stops.
(c) The contactor shall open the
driving-machine brake circuit.
d. Requirements for Electrical Equipment
and Wiring. All electrical equipment and
wiring shall conform to the Philippine
Electrical Code.
e.
(d) An additional contactor shall be
provided to also open the
driving-machine brake circuit.
This contactor is not required to
have contacts in the drivingmachine motor circuit.
Control
and
Operating
Circuit
Requirements. The design and installation
of the control and operating circuits shall
conform to the following requirements:
(e) The electrical protective devices
required by Section 6.4.11.3
shall control the solid state
device and both contactors.
If springs are used to actuate
switches, contactors or relays to
break the circuit to stop and elevator
at the terminal landings, they shall
be of the compression type.
2.
3.
(f) After each elevator stop, the car
shall not respond to a signal to
start unless both contactors are
in the energized position.
The completion or maintenance of
an electric circuit shall not be used
to interrupt the power to the elevator
driving-machine motor or brake at
the terminal landings, not to stop the
car when the emergency stop
switch is opened or any of the
electrical
protective
devices
operate.
Exception: The requirements do not
apply to dynamic braking, nor to
speed control switches.
The
failure
of
any
single
magnetically
operated
switch,
contactor, or relay to release in the
intended manner of the failure of
any static control device to operate
as intended, or the occurrence of a
single accidental ground, shall not
permit the car to start or run if any
hoistway door interlock is unlocked
or if any hoistway door or car door
or gate electric contact is not in the
closed position.
f.
4.
Elevators with driving
motors
employing static control without
motor generator sets shall conform
to the following requirements:
(a) Two devices shall be provided
to remove power independently
from the driving-machine motor.
At least one device shall be an
electromechanical contactor.
a
101
5.
Where generator-field control is
used, means shall be provided to
prevent the generator from building
up and applying sufficient current to
the elevator driving machine to
move the car when the elevator
motor control switches are in the
“OFF” position. The means used
shall not interfere with maintenance
of an effective dynamic-braking
circuit during stopping and stand
still conditions.
6.
The control circuits shall be so
designed and installed that the car
speed in the down direction with
rated load in the car, under normal
operating conditions with the power
supply on or off shall not exceed
governor tripping speed or 125% of
rated speed, whichever is the
lesser. (See Sec. 6.D.8.8).
Load-Weighing Devices on Passenger
Elevators and on Freight Elevators
Load
Permitted to Carry Employees.
weighing devices will prevent operation of
the elevator may be installed provided they
function to prevent such operation only
when the load on the elevator platform is in
excess of 125% of minimum rated load as
determined by the requirements of Sec.
6.D.8.1.
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
g.
Floating
Floating (Movable) Platform.
of the
operation
permit
which
platforms
elevator when the car door or gate is not in
the closed position are prohibited.
h.
Operating Devices Symbols
1.
(b) Means of two-way conversation
between each elevator and
readily accessible point outside
(Telephone,
the hoistway.
intercom, etc.) If the audible
signaling device, or the means
of two-way conversation, or
both normally connected to the
building power supply, they
shall automatically transfer to a
source of emergency power
within 10 sec after the normal
power supply fails. The power
source shall be capable of
providing for the operation of
the audible signaling device for
at least 1 hr and the means of
two-way conversation for at
least 4 hrs.
Where reference is made requiring
wording to designate a specific
function, the following symbols shall
be substituted for, or used in
conjunction with, the required
wording:
0
H
2.
signaling device shall be located
inside the building and audible
inside the car and outside the
hoistway. One signaling device
may be used for a group of
elevators.
2.
Identify the main floor by use of the
following symbol:
*
6.4.12 Emergency
Device
a.
Operation
and
Car Emergency Signaling
Elevators shall be provided
following signaling devices:
1.
In buildings in which a building
attendant, building employee, or
watchman is not continuously
available to take action when the
is
required emergency signal
operated, the elevators shall be
provided with one of the following
emergency signaling
additional
devices:
(a) A telephone connected to a
central telephone exchange
system.
audible
weatherproof
(b) A
a
device with
signaling
minimum sound rating of 80
dB operated from the alarm
switch and the emergency
stop switch inside the car
“ELEVATOR
identified
CALL
EMERGENCY
POLICE” in letters not less
than 51 mm high. The device
shall be mounted on the
outside of the building near
the main entrance and located
so that the sign can be read
from the entrance sidewalk.
Only one outside signal is
Signaling
Devices.
with the
In all buildings, the elevator shall be
provided with the following:
-
(a) An audible signaling device,
operable from the emergency
stop switch and from a switch
marked “ALARM” which are
located in or adjacent to each
The
car operating panel.
102
CHAPTER 6
-
ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
required if operable from all
cars of all elevators of the
type specified in the building.
An emergency power system
shall be provided conforming
to the requirements of Section
6.D.12.1 (a).
shall be provided and the
smoke detectors required by
Sec. 6.D.12.3 (a) (1) shall be
functional. When the switch is in
the “by-pass” position, normal
elevator
shall
service
be
restored independent of the
smoke detectors required by
Section 6.D.12.3 (a) (1) (b).
(c) Means within the car for
communicating
with
or
signaling to an approved
emergency service which
operates 24 hrs each day.
6.4.12.1
When the switch is in the “on”
position:
(1) All cars controlled by this
switch and which are on
automatic
service
shall
return non-stop to the
designated level and the
doors shall
open
and
remain open.
Emergency Power. An elevator may be
powered by an emergency power there is
conformance with the requirements of
Section 6.D.8.8.
Exception: Where the
system is designed to
elevator at a time, the
means, if required, may
power side of the
disconnecting means.
emergency power
operate only one
energy absorption
be located on the
elevator power
(2) A car traveling away from
the designated level shall
reverse at or before the next
available
floor
without
opening its doors.
Other building loads such as power and light
that may be supplied by the emergency
power system shall not be considered as a
means of absorbing the regenerated energy
unless such loads are using their normal
power from the emergency power system
when it is activated.
6.4.12.2
a.
(3) A car stopped at a landing
shall
have
the
in-car
emergency
stop
switch
rendered inoperative as
soon as the door is closed,
and the car starts toward
the designated level.
A
moving car, traveling to or
away from the designated
level, shall have the in-car
emergency
stop
switch
rendered
inoperative
immediately.
Operation of Elevators Under Fire or
Other Emergency Conditions.
All
elevators having a travel of 7.62 mm or
more, above or below the designated level,
shall conform to the requirements of Sec.
6.D.1 2.3.
Phase I and II Operation.
1.
I
Phase
Operation
Emergency
(4) A car standing at a floor
other than the designated
level, with doors open ad
the in-car emergency stop
switch in the run position,
shall
conform
to
the
following:
Recall
(a) A three position (on, off and by
pass) key-operated switch shall
provided only at the
be
designated level for each single
elevator or for each group of
elevators.
The key shall be
removable only in the “on” and
“off” positions.
a.
When the switch is in the “off”
position, normal elevator service
103
Elevators
having
automatic
power
operated
horizontally
sliding doors shall close
the doors without delay
and proceed to the
designated level.
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
b.
Elevators having powervertically
operated
sliding doors provided
or
automatic
with
pressure
momentary
closing operation shall
closing
the
have
initiated
sequence
without delay and the
car shall proceed to the
designated level.
c.
Elevators having powerdoors
operated
with
provided
pressure
continuous
closing operation or
having
elevators
doors.
manual
Sequence operation, if
provided shall remain
effective.
at each floor and associated
elevator machine rooms in
accordance with NFPA No. 72 E
Detectors,
Fire
Automatic
Chapter 4. The activation of a
smoke detector in any elevator
lobby or associated elevator
machine rooms other than the
designated level, shall cause all
cars in all groups that serve that
lobby to return non-stop to the
designated level. If the smoke
detector at the designated level
is activated, the cars shall return
to an alternate level approved
by the enforcing authority
unless the Phase I key-operated
switch [Section 6.D.12.3 (a) (1)
(a)] is in the “on” position.
Smoke detectors and/or smoke
detector system shall not be
The operation
self-resetting.
the
conform
to
shall
Section
of
requirements
6.D.12.3 (a) (1) (a).
(5) Door reopening devices for
doors
power-operated
which are sensitive to
smoke or flame shall be
inoperative.
rendered
Mechanically actuated door
not
devices
reopening
sensitive to smoke or flame
shall remain operative. Car
door open buttons shall
remain operative.
Exception: [Sec. 6.D.12.3 (a) (1)
at
lobbies
elevator
(b)J:
unenclosed landings.
2.
II
Phase
Operation.
Emergency
In-Car
(a) A two-position (off and on) keyshall
switch
be
operated
provided in or adjacent to an
operating panel in each car, and
it shall become effective only
when the designated level
Phase I key-operated switch
[Sec. 6.D.12.3 (a) (1) (a)] is in
the “on” position or a smoke
detector [Sec. 6.D.12.3 (a) (1)
(b)J has been activated, and the
car has returned to the
designated or alternate level.
The key shall be removable only
in the “off’ position. When in
the “on” position, it shall place
the elevator emergency in-car
operation.
(6) All car and corridor call
buttons and all corridor door
opening and closing buttons
rendered
be
shall
inoperative and all call
and
lights
registered
directional lanterns shall be
extinguished and remain
Position
inoperative.
indicators, when provided,
shall remain in service.
(7) All cars shall be provided
with a visual and audible
signal system which shall
be activated to alert the
passengers that the car is
returning non-stop to the
designated level.
6.4.12.3 Floor Numbers. Elevator hoistways shall
have floor numbers, not less than 102 mm in
height, placed on the walls and/or doors of
hoistway at intervals where a person in a
(b) Smoke detectors shall be
installed in each elevator lobby
104
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
stalled elevator upon opening the car door,
can determine the floor position.
safety shall be based on the actual rope
speed corresponding to the rated speed of
the car.
6.4.13 Suspension Rope and their Connections.
f= SXN
6.4.13.1
w
Suspension Means. Elevator cars shall be
suspended by steel wire ropes attached to
the car frame passing around sheaves
attached to the car frame specified in
Section 6.4.4.1.
The factor of safety shall be calculated by
the following formula:
Only iron (low-carbon steel) or steel wire
ropes, having the commercial classification
“Elevator Wire Rope”, or wire rope
specifically constructed for elevator used for
the suspension of counterweights. The wire
material of ropes shall be manufactured by
the open-hearth or electric furnace process
or their equivalent.
N
=
number of runs of rope underload
(see Note)
S
=
manufacturer’s
rated
strength of one rope
breaking
W = maximum static load imposed on all car
ropes with the car and its rated load at
any position in the hoistway
Exception: Elevators with screw machines.
Note: In the case of multiple roping, the
number of runs of rope (N) under load
For 2:1 roping, twice the
will be:
number of ropes used; for 3:1 roping,
three times the number of ropes used,
etc.
6.4.13.2 On Crosshead Data Plate. The crosshead
data plate shall bear the following wire rope
data:
a.
The number of ropes.
b.
The diameter in millimeter.
c.
The manufacturer’s rated breaking strength
per rope in kilograms.
6.4.13.9 Minimum Number and Diameter of
Suspension Ropes. The minimum number
of hoisting ropes used shall be three for
traction elevators, and two for drum-type
elevators.
6.4.13.3 On Rope Data Tag. A metal data tag shall
be securely attached to one of the wire rope
fastenings.
Where a car counterweight is used, the
number of counterweight ropes used shall
be not less than two.
6.4.13.4 Minimum number of hoisting ropes shall be
three (3) for traction elevators and two (2)
for drum-type elevators.
The term “diameter” where used in this
section shall refer to the nominal diameter
as given by the rope manufacturer.
6.4.13.5 Suspension rope tension equalizers shall be
provided.
The minimum diameter of hoisting and
counterweight ropes shall be 9.5 mm.
6.4.13.6 Drum type elevators shall have not less than
one (I) turn of the rope on the drum when
the car is resting on the fully compressed
buffers.
6.4.13.7 Suspension wire ropes shall not
lengthened or repaired by splicing.
Table 6.4.13.8
Minimum Factors of Safety for Suspension Wire Ropes
Rope Speed in Feet per
mm. (fpm)
50
100
150
200
250
300
350
400
be
6.4.13.8 Factor of Safety. The factor of safety of the
suspension wire ropes shall be not less than
shown in Table 6.4.13.8 Fig. 6.4.13.8 gives
the minimum factor of safety for
intermediate rope speeds. The factor of
105
Minimum Factor of Safety
Passenger
Freight
7.6
6.65
7.95
7.00
8.25
7.3
8.6
7.65
8.9
7.9
9.2
8.2
9.5
8.45
9.75
8.7
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
450
500
600
700
1000
1500
NOTE.
rn/s
10.00
1.25
1.7
11.0
11.55
11.9
8.9
9.15
9.5
9.8
10.3
10.55
tapered
babbitted
rope
a.
By individual
sockets; or
b.
By other tyis of rope fastening, if approved
by the enf’cing authority, on the basis of
adequate tensile and fatigue tests made by
a qualified laboratory provided that:
fpm x 0.00508
6.4.13.10 Suspension Rope Equalizers. Suspension
rope equalizers, where provided, shall be of
the individual-compression spring type.
1.
such fastenings conform to the
requirement of Section 6.4.13.15
and 6.4.13.16.
Exception: Equalizers of other types may
be used with traction elevators provided the
equalizers and their fastenings are approved
by the enforcing authority on the basis of
adequate tensile and fatigue tests made by
a qualified laboratory. Such tests shall show
the ultimate strength of the equalizer and its
fastenings in its several parts and assembly,
which shall be not less than 10% in excess
of the strength of suspension ropes as
required by Sec. 6.4.13.8, provided that
equalizers of the single-bar type, or springs
in tension, shall not be used to attach
suspension ropes to cars or counterweights
or to deadened hitchplates.
2.
the rope socketing shall be
to develop at least 80%
ultimate breaking strength
strongest rope to be used
fastenings,; and
3.
U-bolt type rope clips (clamps) shall
not be used for such fastenings.
such as
of the
to the
in such
6.4.13.15 Adjustable Shackle Rods. The car ends,
or the car or counterweight dead ends
where multiple roping is used, of all
suspension wire ropes of traction type
elevators shall be provided with shackle
rods of a design which will permit individual
Similar
adjustment of the rope lengths.
shackle rods shall be provided on the car or
counterweight ends of compensating ropes.
6.4.13.11 Securing of Suspension Wire Ropes to
Winding Drums. Suspension wire ropes of
winding-drum machines shall have the drum
ends of the ropes secured on the inside of
the drum by clamps or by tapered babbitted
sockets, or by other means approved by the
enforcing authority.
6.4.13.16 General Design Requirements. Wire rope
fastenings shall conform to the following:
6.4.13.12 Spare rope-Turns on Winding Drums.
Suspension wire ropes of winding-drum
machines shall have not less than one turn
of the rope on the drum when the car is
resting on the fully compressed buffers.
6.4.13.13 Splicing and Replacement of Suspension
Ropes. Suspension wire ropes shall not be
lengthened or repaired by splicing. If one
rope of a set is worn or damaged and
required replacement, the entire set of ropes
shall be replaced.
6.4.13.14 Type of Rope Fastenings. The car and
counterweight ends of suspension wire
ropes, or the stationary hitch-ends where
multiple roping is used, shall be fastened in
such a manner that all portions of the rope
except the portion inside the rope sockets
shall be readily visible. Fastening shall be:
106
a.
The portion of the rope fastenings which
holds the wire rope (rope socket) and the
shackle rod may be in one piece (unit
construction), or they may be separate.
b.
The rope socket shall be either cast or
forged steel provided that where the rope
socket and the shackle rod are in one piece
(unit construction), the entire fastening shall
be of forged steel.
c.
Where the shackle rod and rope socket are
not in one piece, the shackle rod shall be of
forged or rolled steel.
d.
Cast of forged steel rope sockets, shackle
rods and their connections shall be made of
unwelded steel, having an elongation of not
less than 20% in a length of 51 mm,
conforming to ANSI/ASTM A668, Class B
for forged steel and ANSI/ASTM A27,
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
Grade60/30 for cast steel and shall be
stress relieved.
its outer edge be rounded and free from
cutting edges.
Exception: Steels of greater strength may be
used provided they have an elongation of
not less than 20% in a length of 51 mm.
e.
d.
Where the shackle rod is separate from the
rope socket, the fastening between the two
parts shall be positive and such as to
prevent their separation under all conditions
of operation of the elevator. Where the
connection of the two parts is threaded, the
length of the thread engagement of the rod
in the socket shall be not less than 1 1/2
times the root diameter of the thread on the
rod, and a cotter pin or equivalent means
shall in addition be provided to restrict the
turning of the rod in the socket and prevent
unscrewing of the connection in normal
operation.
Table 6.4.13.18
Relation of Rope Diameter to Diameter of the
Small Socket Hole
Nominal Rope
Diameter, in.
3/8 to 7/16 inclusive
1/2 to 3/4 inclusive
7/8 to 1-1/8 inclusive
1-1/4 to 1-1/2 inclusive
e.
Eye bolts used as connections with clevis
type sockets shall be of forged steel
conforming to ANSI/ASTM A668, Class B
(heat treated) without welds.
f.
g.
h.
6.5.1
Rope sockets shall be of such strength that
the rope will break before the socket is
materially deformed.
6.5.2
The length of the straight bore (Lmm) at the
small end of the socket shall be not more
than 12.70 mm nor less than 3.2 mm, and
Enclosures,
and
Machine Rooms and Machinery Spaces
control equipment are located in spaces
separated from the hoistway enclosure (Sec.
6.3.1.1), such spaces shall be separated from
other parts of the building by enclosures
conforming to the requirements of Sec. 6.3.2.1
(a) and having an access door.
6.5.3 Bottom and Top Clearances and Runby for
Cars and Counteweights
The axial length (I) of the tapered portion of
the socket shall be not less than 4-3/4 times
the diameter of the tope used.
c.
Hoistways, Hoistway
Related Construction.
6.5.2.1 Where pumps, motors, valves, and electrical
Rope fastenings incorporating anti-friction
devices which will permit free spinning of the
rope shall not be used.
The axial length (Lm) of the open portion of
the rope socket shall be not less than four
(4) times the diameter of the rope used.
The diameter (dm) of the hole at the end of
the tapered portion of the socket shall be not
more than shown in Table 6.4.13.18.
6.5.1.1 Hoistways, hoistway enclosures, and related
construction shall conform to the requirements
of the following Sections and Article 6.3.
except Sec. 6.3.7.
The shackle rod, eye bolt, or other means
used to connect the rope socket to the car
or counterweight, shall have a strength at
least equal to the manufacturer’s rated
breaking strength of the rope.
b.
Maximum Diameter of Hole
(d’), in.
3/32 larger than nominal rope dia.
1/8 larger than nominal rope dia.
5/32 larger than nominal rope dia.
3/16 larger than nominal rope dia.
Section 5.0 Hydraulic Elevators
6.4.13.17 Tapered
Babbitted
Rope
Sockets.
Tapered babbitted rope sockets shall be of a
design as shown in Fig. 6.4.13.17, and shall
conform to the following:
a.
The diameter (d) of the hole at the large end
of the tapered portion of the socket shall be
not less than 2-1/4 times nor more than 3
times the diameter of the wire rope used.
6.5.3.1 Bottom Car Clearance. The bottom car
clearances shall conform to the requirements
of Sec. 6.3.7.1, provided that, in
determination of the required clearance,
under-car bracing which is located within
mm horizontally from the edge of the
platform or 76 mm horizontally from
centerline of the guide rails shall not
considered.
107
the
any
152
car
the
be
CHAPTER 6
-
ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
6.5.3.7 Top Clearance and Bottom Runby of
Counterweights. Where a counterweight is
provided, the top clearance and the bottom
runby of the counterweight shall conform to
the following:
6.5.3.2 Minimum Bottom and Top Car Runby. The
bottom and top car runby shall be not less
than:
a.
76 mm for rated speeds not exceeding 0.51
m/s;
b.
152 mm for rated speeds exceeding 0.51
rn/s
The top
(a) Top Clearance.
clearance shall be not less than
the sum of the following:
(1) The bottom car runby.
6.5.3.3 Maximum Bottom and Top Car Runby. The
bottom and the top car runby shall not be
more than 610 mm.
(2) The stroke of the car buffers
used.
6.5.3.4 Top Car Clearance. The top car clearance
shall be not less than the sum of the following
two items:
a.
The top car runby.
b.
The largest of the following:
(3) 152 mm.
The bottom
(b) Bottom Runby.
than the
less
not
shall
be
runby
sum of the following:
1.
610 mm above the car crosshead
where a crosshead is provided.
(1) The distance the car can
travel above its top terminal
landing until the plunger
strikes its mechanical stop.
2.
The height of the refuge space on
top of the car enclosure.
(2) 152 mm.
3.
for
required
clearance
The
equipment projecting above the car
top (Sec. 6.5.3.5).
The minimum runby specified
shall not be reduced by rope
stretch.
6.5.4
6.5.3.5 Equipment Projecting Above the Car Top.
When the car reaches its maximum upward
movement and refuge space is provided, all
shoe
of guide
exclusive
equipment,
assemblies or gate posts for vertically sliding
gates, attached to and projecting above the
car top, shall be at least 152 mm from striking
any part of the overhead structure or any
equipment located in the hoistway.
6.5.4.1 Where the space below the hoistway
is used for a passageway, is occupied
by persons, or, it is unoccupied, is not
secured against unauthorized access,
the following requirements shall be
conformed to:
(a) The cylinder shall be supported
by a structure of sufficient
strength to support the entire load
that may be imposed upon it.
6.5.3.6 Overhead Obstructions in Hoistway. When
overhead beams or other overhead hoistway
construction except sheaves are located
vertically over the car, but not over the
crosshead, the following requirements shall be
met:
a.
The clearance from the car top to such
beams or construction when the car is level
with the top landing shall be not less than
the amount specified in Sec. 6.5.3.4.
b.
Such beams or constructions shall be
located not less than 610 mm horizontally
from the crosshead.
Protection of Spaces Below Hoistway
is
counterweight
a
(b) Where
provided, the space below it shall
be inaccessible to persons or the
counterweight shall be provided
with a safety device operated as
a result of breaking or slackening
of the counterweight suspension
ropes.
108
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
(c) The car shall be provided with
buffers of one of the following
types:
1.
6.5.5.3 Counterweight
Safeties.
Counterweight
safeties, where provided in accordance with
the requirements of Sec. 6.5.4.1 (b), shall
conform to the requirements of Sec. 6.4.6,
provided that safeties shall be operated as a
result of the breaking or slackening of the
counterweight suspension ropes, irrespective
of the rated speed of the elevator.
Spring buffers of a design
which will not be fully
compressed when struck by
the fully loaded car at the
maximum speed attained in
the down direction.
6.5.5.4 Capacity and Loading. The requirements of
Section 6.4.8 covering capacity and loading
shall apply to hydraulic elevators, provided
that with Class C2 loading the load during the
loading and unloading shall not exceed the
rated load of the elevator unless all parts of
the hydraulic equipment are designed for the
maximum pressure developed as a result of
this load.
(d) Car buffer supports shall be
provided which will withstand
without permanent deformation
the impact resulting from buffer
engagement by the car with its
rated load at the maximum speed
attained in the down direction.
Mechanical Equipment
6.5.5
6.5.6
6.5.5.1 Information on Elevator Layout. Elevator
layout drawings shall, in addition to other data,
indicated the following:
a.
The bracket spacing.
b.
The estimated maximum vertical forces on
the guide rails on the application of the
safety, where provided.
c.
d.
6.5.6.1 Driving Machine and Connection
For freight elevators with Class B or C
loading, the horizontal forces on the car
guide rail faces during loading and
unloading and the estimated maximum
horizontal forces in a postwise direction on
the guide rail faces on the application of the
safety, where provided.
Outside diameter and wall thickness of
cylinder plunger, and piping and the working
pressure.
6.5.5.2 Car Safeties. Car safeties where provided
shall conform to the requirements of Section
6.4.6 and to the following:
a.
b.
Driving Machine
a.
Type of Driving Machine. The machine
shall be of a direct plunger type or indirect
plunger (suspension type).
b.
Connection to Driving Machine:
1.
the driving member of the driving
machine shall be attached to the car
frame or platform with fastenings of
sufficient strength to support that
member with a factor of safety of
not less than 4.
2.
Indirect plunger or Suspension type:
Where the raising of lift is achieved
by the use of ropes or chains
interposed between the ram and the
car, the following requirements shall
apply:
(a) Ropes shall correspond to the
following conditions:
(1) The nominal diameter of the
ropes shall be at least 8 mm
The safety shall be of a type which can be
released only by moving the car in the up
direction.
(2) The tensile strength of the
wire shall be:
The switches required by Sec. 6.4.7.5 shall,
when operated, remove power from the
driving machine motor and control valves
before or at the time of application of the
safety.
2.1
109
1570 N/mm or
1770 N/mm for
ropes of single
tensile.
CHAPTER 6
-
ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
2.2
(c) Plunger Stops. Plungers shall
be provided with solid metal stops
and/or other means to prevent the
plunger from traveling beyond the
limits of the cylinder. Stops shall
be so designed and constructed
as to stop the plunger from
maximum speed in the up
direction under full pressure
without damage to the hydraulic
For rated speeds
system.
exceeding 0.51 rn/s where a solid
metal stop is provided, means
other than the normal terminal
stopping device shall be provided
to retard the car to 0.51 mIs with a
retardation not greater than
gravity, before striking the stop.
(See Sec. 6.5.7.7).
1370 N/mm for
the outer wires
and 1660 N/mm
for the inner
wires of ropes of
dual tensile.
(3) The ratio between the
of
diameter
pitch
sheaves and pulleys
nominal
the
and
the
of
diameter
ropes
suspension
shall be at least 40,
of the
regardless
number of stands.
6.5.6.2 Plungers
(a) Plunger Connection. Where the
plunger is the driving member and
is subjected to eccentric loading,
the following requirements shall
apply:
A
(d) Plunger-Follower Guide.
plunger-follower guide may be
used provided it is arranged so
that the elevator is always in a
position where the unsupported
length of the plunger conforms to
the ‘maximum free length”, and to
open the power circuit if this
length is exceeded.
(1) The plunger connection to the
car shall also be so designed
and constructed as to transmit
the full eccentric moment into
the plunger with a factor of
safety of not less than 4.
6.5.6.3 Cylinders
The cylinder and
(a) Materials.
connecting couplings for the
cylinder shall be of materials with
a factor of safety of not less than
5 based on the ultimate strength
and with an elongation of not less
than 10% in 51 mm.
(2) The plunger and the plunger
connection to the car shall
also be so designed and
constructed that the total
vertical deflection of the
loading edge of the car
platform due to eccentric
loading of the car shall not
exceed 19 mm.
of
Bottom
at
(b) Clearance
Clearance shall be
Cylinder.
provided at the bottom of the
cylinder so that the bottom of the
plunger will not strike the safety
bulkhead of the cylinder when the
car is resting on its fully
compressed buffer.
Plungers
(b) Plunger Joints.
composed of more than one
section shall have joints designed
and constructed to:
(1) carry in tension the weight of
all plunger sections below the
joint with a factor of safety of
not less than 4; and
(c) Cylinder and Plunger Heads.
Heads of cylinders, and heads of
plungers subject to fluid pressure,
shall conform to the following
requirements:
(2) transmit in compression the
gross load on the plunger with
a factor of safety of not less
than 5 based on ultimate
strength.
Bottom
(1) Cylinder Heads.
heads of cylinders only shall
110
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
dished
be
of
seamless
construction,
concave
to
pressure.
cylinder head. Safety bulkheads
shall conform to the requirements
of Section 6.5.6.3
Exception: If the bottom of
the cylinder is supported and
if the cylinder is not below
ground, Sec. 6.5.6.3 (c) (1)
does not apply.
Exception:
Where a double
cylinder is used and where both
inner and outer cylinders conform
to the requirements of Sction
6.5.6.3.
(2) Dished Seamless Heads,
Convex to Pressure. Dished
seamless head, convex to
pressure if used on plungers,
have
shall
a
maximum
allowable working pressure of
not more than 60% of that for
of
the
heads
same
dimensions with pressure on
the concave side.
6.5.6.4 Welding
(a) Welding of part on which safe
operation depends shall be done
accordance
in
with
the
appropriate standards established
by the American Welding Society.
(b) All welding of such parts shall be
done by welders qualified in
accordance with the requirements
of the American Welding Society.
At the option of the manufacturer,
the welders may be qualified by
one of the following:
(3) Reinforced
Heads.
Reinforced heads shall be
designed and constructed so
that the maximum stress at
rated
capacity shall
not
exceed 83 MPa for mild steel
and 1/5 of the ultimate
strength of the material for
other metals.
(1) The manufacturer
professional
(2) A
engineer
(4) Heads
Subjected
to
Mechanical
Loads
in
Addition to Fluid Pressure
Loads.
Pressure heads
subjected to mechanical load
in addition to fluid pressure
load shall be designed and
constructed that the combined
stress will not exceed the
limits specified in Section
6.5.6.3 (c) (2) and (3).
consulting
recognized
(3) A
laboratory
testing
Exception
(Sec. 6.5.6.4):
welds
later
Tack
not
into
finished
incorporated
carrying
calculated
welds
loads.
6.5.7
Valves, Supply Piping, and Fittings
6.5.7.1 Valves, Supply Piping, and Fittings
(d) Means for Relief of Air or Gas.
Cylinders shall be provided with a
means to release air or other gas.
Valves,
(a) Working Pressure.
piping, and fittings shall not be
subjected to working pressure
exceeding those recommended
by the manufacturer for the type
of service for which they are used.
(e) Safety Bulkhead.
Cylinders
installed below ground shall be
provided with a safety bulkhead
having an orifice of a size that
would permit the car to descend
at a speed not greater than 0.076
rn/s nor less than 0.025 m/s. A
space of not less than 25 mm
shall be left between the welds of
the safety bulkhead and the
Threads of valves,
(b) Threads.
piping and fittings shall conform to
standards on
Pipe Threads
(Except Dryseal).
111
S
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALK
more than 6 years beyond
the installation date.
(c) Pipe Supports. Piping shall be so
supported as to eliminate undue
stresses at joints and fittings,
particularly t any section of the
line subject to vibration.
(2) Flexible couplings shall be so
designed and constructed that
failure of the sealing element
will not permit separation of
the parts connected.
(d) Flexible Hydraulic Connections.
fitting
and
hose
Flexible
flexible
and
assemblies,
couplings, mv be used for
Where
hydraulic connections.
valve
check
the
between
installed
or control valve and the cylinder,
they shall conform to the following
requirements:
(1) Flexible hose and
assemblies shall:
6.5.7.2 Relief and Check Valves
(a)
fitting
Each
Pump Relief Valves.
be
shall
pumps
of
group
pump or
equipped with a relief valve
conforming to the following
requirements:
The
(1) Type and Location.
located
relief valve shall be
between the pump and the
check valve and shall be of
such a type and so installed in
the by-pass connection that
the valve cannot be shut off
from the hydraulic system.
(a) not be installed within the
hoist-way, not project into
or through any wall.
be
shall
Installation
without
accomplished
intro-ducing twist in the
hose, and shall conform
with the minimum bending
radius of SAE 100 R2
type, High Pressure, Steel
Wire Reinforced, Rubber
Covered Hydraulic Hose
specilied in SAE J517D.
(2) Setting. The relief valve shall
be preset to open at a
pressure not greater than
125% of working pressure.
(3) Size. The size of the relief
valve and by-pass shall be
the
pass
to
sufficient
maximum rated capacity of
the pump without raising the
pressure more than 20%
above that at which the valve
opens. Two or more relief
valves may be used to obtain
the required capacity.
(b) have a bursting strength
sufficient to withstand not
times
10
than
less
working pressure. They
shall be tested in the
factory or in the field prior
to installation at the
pressure of not less than
5 times working pressure
and shall be marked with
date and pressure of test.
(4) Sealing. Relief valves having
pressure
exposed
shall
used,
if
adjustments,
of
means
their
have
after
sealed
adjustments
being set to the correct
pressure.
(c) be compatible with the
fluid used;
(d) be of non-reusable type
fittings;
Exception [Sec. 6.5.7.2 (a)]:
No relief valves is required for
centrifugal pumps driven by
induction motors, provided the
maximum
or
shut-off,
pressure which the pump can
develop, is not greater than
(e) be permanently marked
with the SAE hose type
the
and
identification
replacement
required
date which shall not be
112
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
135% of the working pressure
at the pump.
(b)
excess of 0.51
6.5.6.2 (c)j.
Check Valve.
A check valve
shall be provided and shall be so
installed that it will hold the
elevator car with rated load at
any point when the pump stops
or the maintained pressure drops
below the minimum operating
pressure.
(b) Requirements.
Emergency
terminal speed limiting devices
shall conform to the following:
(1) They
shall
operate
independently of the normal
terminal stopping device and
shall function to reduce the
speed of the car should this
device fail to slow down the
car at the terminals as
intended.
6.5.7.3 Material.
Supply piping materials,
valves, and fittings shall conform to
the applicable provision of Power
Piping
except
that
nonductile
materials shall not be used. The other
materials that may be used shall have
a factor of safety of not less than 5
based on tensile strength and an
elongation of not less than 10%.
(2) They shall provide retardation
not in excess of 9.81 m/s
.
2
(3) They shall be so designed
and installed that a single
short circuit caused by a
combination of grounds or by
other conditions shall not
prevent their functioning.
Exception:
Flexible hydraulic hose
and fitting assemblies, and flexible
couplings.
6.5.7.4 Wall Thickness. The minimum wall
thickness shall conform to the
following requirements:
(4) Control Means Affected.
(a)
Direct
Plunger
(Maintained Pressure
Type). The emergency
terminal
and
normal
terminal
stopping
devices shall not control
the
same
controller
switches to complete the
circuit to the control
valves unless two or
more
separate
and
independent
switches
are provided, two of
which shall be closed in
the appropriate direction
of travel.
(b)
Electro-Hydraulic. For
the up direction of travel
at least two control
means are required, one
or both to be controlled
by the emergency speed
limiting device and the
other or both by the
normal terminal stopping
device.
If, in the up
direction,
the
pump
motor is the only control
(a) For working pressure up to 1,72
MPa, piping equal to standard
schedule 40 steel pipe may be
used without stress analysis.
6.5.7.5 Threading.
Pipe lighter than
Schedule 40 shall not be threaded.
6.5.7.6 Supply Line Shut-Off Valve. A
manual shut-off valve shall be
installed in the supply line to the
cylinder of every hydraulic elevator
where the cylinder is not exposed to
inspection. The shut-off valve shall be
located in the machine room.
6.5.7.7 Emergency
Terminal
Limiting Devices.
m/s [see Sec.
Speed
(a) Where Required. Emergency
terminal speed limiting devices
shall be installed where a
reduced stroke buffer is used and
for the up direction where the car
speed exceeds 0.51 m/s to insure
that the plunger does not strike its
solid limit of travel at a speed in
113
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
range of the free suspension of the car and
not exceeding 76 mm.
means, two magnetic
switches, both of which
closed
to
shall
be
the
motor
complete
circuit, are required to
If,
satisfy this rule.
the
pump
however,
motor is one control
means and there is a
second control means,
(e.g., a valve) only one
magnetic switch for the
pump motor is required.
For the down direction,
the emergency terminal
and
speed
limiting
normal terminal stopping
devices
shall
each
or
through
directly
separate switches affect
the control valve. Where
two magnetic switches
are used, the emergency
terminal speed limiting
terminal
normal
and
stopping devices each
may control one or both.
b.
The enclosure may be omitted on the upper
landing on continuous pressure operation
elevators serving only adjacent landings
(one floor travel) provided the floor opening
at the upper landing is protected by an
enclosure and gate at least 914 mm high
with openings that will reject a ball 25 mm in
diameter and the gate is provided with a
combination mechanical lock and electric
contact.
c.
The enclosure may be omitted on the upper
landing of elevators having continuous
pressure operation and serving only
adjacent landings (one floor travel), where
the floor opening is provided with a vertically
lifting hatch cover which is automatically
raised and lowered vertically by he
ascending and descending car, provided
this cover meets the following requirements:
1.
It is fitted with guides to insure its
proper setting.
2.
It is designed and installed to
sustain a total load of 3.59 kPa or
136 kg at any one point.
3.
It is equipped with an electric
contact which will prevent the
upward travel of the car when a
force of 9 kg is placed at any point
on the top of the hatch cover.
6.5.7.8 Final Terminal Stopping Devices. Final
terminal stopping devices are not required.
Section 6.0 Private Residence Elevators
6.1
Hoistway, Hoistway Enclosures, and Related
Construction
6.1.1 Hoistway Enclosure Construction.
The
hoistway shall be solidly enclosed throughout its
height without grillwork or openings other than
for landing or access doors, except that exterior
windows within the hoistway shall be of
sufficient strength to support in true alignment
the hoistway doors and gates and their locking
equipment. The fire resistance rating shall be in
accordance with the requirements of Section
6.3.1.1 (b).
a.
d.
The enclosure may be omitted on the lowest
landing served, unless it opens directly into
a garage, provided the car platform is
equipped with a device which if the platform
is obstructed in its downward travel by a
force of 1.8 kg or more applied anywhere at
its lower surface, will open an electric
contact in the control circuit and thus stop
the downward travel of the car within the
The hoistway enclosure may be omitted on
elevators located in existing open stairway
areas or other existing open areas provided
that:
1.
The car platform is equipped with a
which
will
meet the
device
requirements of Section 6.6.1.1 (a)
stop the car if it is obstructed in its
downward travel;
2.
The car gate is automatically locked
except when the car platform is
within 152mm of a landing.
Pits
6.1.2
a.
Pits Maintenance. Where a pit is provided,
it shall be kept clean and free from dirt and
rubbish.
The pit shall not be used for
114
I
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
storage purposes and shall be maintained
free of an accumulation of water.
b.
sides and on the top. The enclosures shall
be constructed of solid or of openwork
material which will reject a bell 12.70 mm in
diameter.
Pit Guard. A pit provided in other than a
hoistway that is enclosed for its full travel of
the car shall be guarded by a railing at least
914 mm high and the entrance shall be
provided with a door or gate.
6.1.3
Top Car Clearance. The top car clearance
shall be not less than 152 mm plus 25 mm for
each 0.07 m/s of the rated speed in excess of
0.15 m/s.
6.1.4
Between Car and Hoistway Enclosures or
Counterweight. There shall be a clearance of
not less than 19 mm between the car and the
hoistway enclosure, and between the car and
its counterweight.
6.1.5
Between Car and Landing Sill.
The
clearance between the car platform and the
landing sill shall be not less than 13 mm nor
more than 38 mm.
6.1.6
Guarding of Suspension Means
b.
Securing Enclosures. Car enclosures shall
be secured in conformance with the
requirements of Sec. 6.4.5.2 and 6.4.5.3.
c.
Glass in Elevator Cars. Glass, where used
in elevator cars, shall conform to the
requirements of Sec. 6.4.5.7.
6.2.3
a.
6.2
Collapsible car gates shall be of a design that,
when fully closed (extended position), will
reject a ball 76 mm in diameter.
Suspension Means Passing Through
Floors or Stairs.
Ropes and chains
passing through a floor or stairway outside
the hoistway enclosure shall be enclosed
with a solid or openwork enclosure. If or
openwork, the enclosure shall reject a ball
12.70 mm in diameter. Means for inspection
shall be provided. The floor openings shall
not be larger than is necessary to clear the
suspension means.
Car Frames and Platforms. Materials used
in construction of car enclosures, frames, and
platforms shall conform to the following:
a.
Cars shall have a metal or combination of
metal and wood car frames and platforms
having a factor or safety of not less than 5
based on rated load.
b.
Cast iron shall not be used in any member
of the car frame or platform other than for
guides or guide shoe brackets.
6.2.2
6.2.4
6.3
Car Enclosure.
a.
a.
Car Door or Gate Locking Devices.
Where the hoistway enclosure is not
continuous for the full travel of the car, the
car door or gate shall be provided with a
mechanical lock that will lock the car door or
gate if the car is more than 152 mm away
from a landing.
b.
Car Door or Gate Electric Contacts.
Every car door or gate shall be provided
with an electric contact.
The design of the car door or gate electric
contacts shall be such that for a sliding door
or gate, the car cannot move unless the
door or gate is within 51 mm of the closed
position. If the door or gate swings outward
to open, the car door or gate must be closed
and locked before the car can move.
Cars
6.2.1
Car Doors and Gates. A car door or gate
which, when closed, will guard the opening to
a height of at least 1680 mm shall be provided
at each entrance to the car. Car doors may
be of solid or openwork construction which will
reject a ball 76 mm in diameter.
6.3.1
Car Enclosure Required. Except at
entrances, cars shall be enclosed on all
115
Light in Car. The car shall be provided with
an electric light. The control switch for the
light shall be located in the car and near the
car entrance. The minimum illumination at the
car threshold, with the door closed, shall be
not less than 54 lx.
Safeties and Governors
Safeties Required. Each
provided with a car safety.
below the hoistway is
secured against access,
elevator shall be
Where the space
not permanently
the counterweight
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
6.5.4
shall be provided with a safety conforming to
the requirements of Section 6.63.2.
6.3.2
6.4
6.4.1
Operation of Safeties. The car safety shall
be of the inertia or other approved type
operated by the breakage of the suspension
means or by the action of a speed governor.
If of the speed governor type, the governor
shall operate the safety at a maximum speed
On the breakage of the
of 0.38 mis.
suspension means, the safety shall operate
without delay and independently of the speed
governor action.
Section 7.0 Hand and Power
Dumbwaiters
7.1
7.1.1
Limitation of Load, Speed, and Rise
Capacity. The rated load shall not exceed 318
kg and maximum inside net platform area
. the minimum rated
2
shall not exceed 1.1 m
load shall be not less than that based on 1.91
kPa of inside net platform area of 159 kg
whichever is greater.
6.4.2
Speed. The rated speed shall not exceed 0.20
m/s.
6.4.3
Rise. The rise shall not exceed 15 m.
6.5.2
6.5.3
Hoistway
Hoistways,
Related Construction
Enclosures,
and
Hoistways,
Applicable Requirements.
hoistway enclosures, and related construction
shall conform to the requirements of Article
6.3 except for the following Sections which do
not apply:
Sec. 6.3.1.1(d) Strength of Enclosure
Sec. 6.3.1.2
Floor Over Hoistways
Sec. 6.3.2.1 (a) Enclosures Required
for Elevators Having
Fire-Resistive
Hoistway Enclo-sures
in
Sec. 6.3.2.2
Equipment
Machine Rooms
Suspension Ropes. On elevators having a
rated load of 204 kg or less and operating at a
rated speed of 0.15 mis or less, ropes shall be
not less than 6.3 mm in diameter. Where the
rated load exceeds 204 kg or the rated speed
exceeds 0,15 rn/s the ropes shall be not less
than 9.5 mm in diameter.
Sec. 6.3.2.7
Headroom in Machine
Rooms and Overhead
Machinery Spaces
Factor of Safety of Suspension Means.
The factor of safety of the suspension means
shall be not less than 7 based on the
manufacturer’s rated breaking strength.
Sec. 6.3.4
Guarding of Exposed
Auxiliary Equipment
Sec. 6.3.6
Pits
When the car and counterweight are
suspended by steel ropes and the driving
means is an endless steel roller type chain,
the factor of safety of such chain with the
rated load in the car shall be not less than 8
based on the ultimate tensile strength.
Sec. 6.3.7
Top
and
Bottom
and
Clear-ances
Runbys for Elevator
Count
and
Cars
erweights
Sec. 6.3.8
Horizontal Car
Count-erweight
Clearance
6.5 Suspension Means
6.5.1
Replacement of Chains and Sprockets. If
chains are used as a suspension means and a
worm chain is replaced, all chains must be
replaced. If a chain sprocket is replaced due
to wear, all sprockets must be replaced.
for
Sec. 6.3.2.8 (b) Ventilation
and
Machinery
Control Equipment
Arc of Contact of Suspension Means on
Sheaves and Sprockets. The act of contact
of a wire rope on a traction sheave shall be
sufficient to produce traction under all load
conditions up to rated load. The arc of contact
of a chain with a driving sprocket shall not be
less than 140 deg.
7.1.2
116
and
and
Rooms
Machine
Enclosures
for
power
and
Hand
Machinery
Spaces
dumbwaiter machines and their control
equipment may be located inside the hoistway
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
conspicuously displayed on the landing side in
letters not less than 51 mm high, the words:
“DANGER-DUMBWAITERS-KEEP CLOSED.”
enclosure at the top or bottom without
intervening enclosures or platforms.
Power dumbwaiter machines and control
equipment located outside the hoistway shall
be enclosed as required for electric elevators
by Sec. 6.3.2.1 (a) except that control
equipment located outside the hoistway may
be enclosed in a metal cabinet equipped to
prevent access by unauthorized persons.
7.1.3
Pits. Pits are not required.
7.1.4
Types of Entrances
7.1.7
Size and
Openings
a.
For Power Dumbwaiters. Entrances shall
be one of the following types:
slide,
Horizontal
section.
2.
Swing, single-section.
3.
Combination
swing.
horizontal
slide
Size of Openings. The width and
height of openings shall not exceed
the width and height of the car by
more than 25 mm in each
dimension.
and
2.
biparting
Hoistway-Door
Exception: One door opening may
be of sufficient size to permit
installing and removing the car, but
shall not be more than 1450 mm in
height.
single or multi-
1.
of
For Power Dumbwaiters. The size and
location of openings shall conform to the
following:
1.
a.
Location
4.
Vertical slide
balanced.
counter
5.
Vertical slide counterweight, singleor multi-section.
Location of Door Opening. The
bottom of the door opening shall be
not less than 610 mm above the
floor.
Exceptions:
(1) Undercounter dumbwaiters.
b.
For Hand Dumbwaiters. Entrances shall
be one of the following types:
1.
2.
7.1.5
(2) Dumbwaiters where load is
handled on wheel trucks.
Manually operated vertical slide
counterweighted, single or multisection.
Manually operated vertical
biparting counter-balanced.
(3) Dumbwaiters having hoistway
doors equipped with hoistway
door interlocks.
slide
of the
the
sill
(4) Where
dumbwaiter landing is 1520
mm of the pit floor.
of
Hand
Closing
Hoistway
Doors
Dumbwaiters. All doors shall be kept closed
except the door at the floor at which the car is
being operated or is being loaded or
unloaded.
b.
Manually operated doors shall be equipped
with approved devices to close them
automatically when released by heat. Selfclosing doors may be equipped with hold-open
devices provided that such devices shall be
equipped with fusible links which will release
the doors in case of excessive heat.
7.1.6
Signs on Hoistway Doors of Hand
Dumbwaiters. Every hoistway door shall have
7.1.8
117
For Hand Dumbwaiters. The width of the
door opening shall not exceed the width of
the car by more than 152 mm, and the
maximum height of the opening for any
height of the car shall be 1370 mm. The
bottom of the door openings shall be not
less than 610 mm above the floor at each
landing; except that for the upper landing of
undercounter dumb-waiters, the bottom of
the opening shall be not less than 102 mm
above the floor.
Rails for Entrances, Vertical Slide Type.
The panel guide rails shall conform to the
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
machines and their control equipment located
Access
inside the hoistway enclosure.
requirements of Sec. 6.3.9.1 (c), except that
they may be fastened only to the entrance
frame.
openings shall:
(a) be of adequate size and so located as to
permit required maintenance and inspection;
Overlap of Entrance Panels for Entrances,
Vertical Slide Type. The entrance panels
with their attachments shall overlap the
entrance frame and sill by not less than 12.7
mm.
7.1.9
(b) have a maximum width of 610 mm and
maximum height of 610 mm.
(c) be provided with doors which shall be kept
closed and locked.
7.1.10 Hoistway-Door Locking Devices
a.
For Power Dumbwaiters
7.2
At landings where the bottom of the
door opening 610 mm or more
above the floor, the hoistway doors
shall be provided with hoistway-unit
system hoist-way door combination
mechanical locks and electric
contacts.
2.
Exceptions:
Hoistway-unit-system
hoist-way
door
combination
locks and
electric
mechanical
contacts may be used for hoistway
under
following
doors
the
conditions:
2.
b.
Dumbwaiters with a travel of
4570 mm or less: For the top
landing door and for any door
whose sill is located not more
than 1220 mm below the sill
of the top landing door.
a.
openwork
They shall
be of solid
construction, and of such strength and
stiffness that they will not deform
appreciably when the load leans or falls
against the sides of the cars.
b.
Non-metal cars sections shall be reinforced
with metal from the bottom of the car to the
point of suspension.
c.
Metal car sections shall be riveted, welded,
or bolted together.
d.
Cars may be provided with
permanent, or removable shelves.
e.
The total inside height of the car shall not
exceed 1220 mm.
f.
Cars shall be provided with a platform.
hinged,
Exception: Sec. 6.7.2.1 (f): The platform
floor may be made hinged or removable or
may be omitted in non-residential buildings,
subject to the approval of the enforcing
authority.
Dumbwaiters with any travel:
For any door whose sill is
within 1520 mm of the bottom
of the pit.
Note Sec. 6.7.2.1 (f): The omission of the
platform floor is frequently desired by
department stores, dress manufacturers,
similar
clothing
and
manufacturers,
establishments in order to carry dresses,
coats, etc. which are longer than the 1220
mm height permitted for the car.
For Hand Dumbwaiters. Hoistway doors
shall be provided with spring-type latches to
hold them in the position. Such latches may
be released from both the hoistway and
landing side, irrespective of the position of
the car.
7.3
7.1.11
Construction of Cars. Cars shall conform to
the following requirements:
7.2.1
At landings where the bottom of the
door opening is less than 610 mm
above the floor, the hoistway doors
shall be provided with hoistway-unit
system hoistway door interlocks.
1.
Cars
Hoistway Access Doors. Access opening
shall be provided in the hoistway enclosure for
maintenance and inspection of dumbwaiter
7.3.1
118
Capacity and Loadings
Maximum Rated Load and Maximum Inside
Net Platform Area
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
Maximum
a.
Rated Load.
The
rated load shall not exceed 1,000
kilograms.
b.
Maximum Inside Net Platform
Area.
The inside net platform
area shall not exceed 1.00 square
Belt-Drive Machine.
Belts used as the
driving means between the motor and the
machine of power dumbwaiters shall conform
to the following requirements:
7.5.3
a.
Where flat belts are used, the rated speed
shall be not more than 0.25 m/s.
b.
Where multiple V-belts are used, the rated
speed shall be not more than 0.76 rn/s.
meters.
7.3.2
7.4
Capacity Plate.
A metal
plate shall be
fastened in a conspicuous place in the car and
shall indicate the rated load in letters and
numerals not less than 6.3 mm high, stamped,
etched, or raised on the surface of the plate.
Car and Counterweight Safeties
7.4.1
a.
Electric driving machines shall have
electrically
released
brakes
applied
automatically by springs in compression or
by gravity when power is removed from the
motor.
b.
Hand driving machines shall be equipped
with handbrakes or automatic brakes which
will sustain the car and its rated load. When
the brake is applied, it shall remain locked in
the “On” position until released by the
operator.
Where
Required. Car and counterweight
safeties shall not be required except for
protection of spaces below hoistway for all
dumbwaiter cars and counterweights having a
rated load over 11.3 kg. Where required, the
car and counterweight safeties may be
operated as a result of breaking the
suspension means and may be of the inertia
type without governors. Car safeties may be
located in the car crosshead.
7.5 Driving Machines and Sheaves
7.5.1
7.5.2
Driving-Machine Brakes. Electric and hand
driving machines shall be equipped with
brakes as follows:
7.5.4
Exception Sec. 6.7.5.4 (b): For rated loads
of 9.1 kg or less, the brake may be omitted
provided the machine has sufficient friction
to hold the car and its rated load at any
floor.
Types
Power
of
Driving
Machines
Permitted. Driving machines shall be one of
the following types:
a.
Winding-drum
b.
Traction
c.
Rack and Pinion
d.
Screw
e.
Direct-Plunger
f.
Belt-Drive
g.
Chain-Drive
h.
Roped-Hydraulic
—
7.5.5
Hydraulic Dumbwaiters. Hydraulic driving
machines, valve, supply piping, fittings and
tanks shall conform to the requirements of
Section 6.5.6, 6.5.7.
Exception: when roped-hydraulic machines
are used, design need not conform to the
requirements of Section 6.5.5.1, 6.5.6.2 and
6.5.6.3 (b).
Single Belt
7.6
Factor of Safety of Driving Machines and
Sheaves.
Driving machines and sheaves
shall be designed with a factor of safety,
based on the static load (the rated load plus
the weight of the car, ropes, counterweights,
etc.) of not less than 6 for steels, and 9 for
cast iron and other materials.
119
Car and Counterweight Guides and Guide
Fastenings
7.6.1
Guides for Dumbwaiters Having a Capacity
of more than 9.1 kg. Car and counterweight
guides shall be of metal, wood, or wood and
metal bolted together.
7.6.2
Guides for Dumbwaiters Having a Capacity
of 9.1 kg or less. Car and counterweight
guides shall be of metal, wood and metal
bolted together, metal tubes, or spring steel
wires maintained in tension.
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
7.6.3
Use of the Set of Guides for Car and
Counterweight. The same set of guides may
be used for both the car and counterweight.
7.6.4
Guide Fastenings and Joints. Guides shall
be securely fastened to the hoistway.
b.
Rated Loads of 34.0 kg or less.
Dumbwaiters having a rated load of 34.0 or
less may be suspended by manila or
braided-cotton ropes having a factor of
safety of not less than 6.
Section 8.0 Escalators
Guide joints shall be either tongue and groove
or doweled and fitted and splice plates.
7.7
Counterweights
Protection of Floor Openings
Protection Required. Floor openings for
escalators shall be protected against the
passage of flame, heat and/or smoke in
accordance with provision of the local codes.
8.1.1
Design of Counterweights. Counterweights
for dumbwaiters, having a capacity of more
than 45.4 kg and a rated speed of more than
0.51 m/s, shall be of either solid or section
construction. If made in sections, the sections
shall be secured by not less than two tie rods
passing through holes in all section except
where metal counterweight frames are
provided. Tie rod shall have lock nuts secured
by cotter pins.
7.7.1
7.8
8.1
8.2
Protection of Trusses and Machine Spaces
Against Fire
The sides and
Protection Required.
and
undersides of escalators trusses
machinery spaces shall be enclosed in fireresistive materials. Means may be provided
for adequate ventilation of the driving machine
and control spaces.
8.2.1
Means of Suspension and Fastenings
and
Cars
Dumbwaiters.
Power
counterweights, except for dumbwaiters
having direct-plunger hydraulic or rack and
pinion of screw-type driving machine, shall be
suspended by one or more iron or steel-wire
hoisting ropes or chains secured to the car on
counterweight or rope hitch by babbitted
sockets, rope clamps, or equally substantial
Wire ropes may have marlin
fastenings.
covers.
7.8.1
7.8.2
Types of Chains Permitted for Power
Dumbwaiters. Chains where used shall be
roller, block or multiple-link silent type.
7.8.3
Factors of Safety for Power Dumbwaiters.
The factor of safety, based on the static load,
of car and counterweight suspension means
shall be not less than the value specified in
Table 6.7.8.3 for actual speed of rope or chain
corresponding to the rated speed of the
dumbwaiter.
8.3
Construction Requirements
8.3.la Geometry. The width between balustrades
shall be measured on the incline at a point
636 mm vertically above the nose line of the
steps, and shall not be less than the width of
the step. It shall not exceed the width of the
step by more than 330 mm with a maximum of
163 mm on either side of the escalator. The
handball shall be a minimum of 102 mm
horizontally and 25 mm vertically away from
adjacent surfaces. The center line of the
handrail shall be not more than 254 mm,
measured horizontally, from the vertical plane
through the edge of the exposed treadway.
(See Sec. 6.8.3.3 (b) for step width
requirements and Fig. Fl, Appendix F.)
8.3.lb Inclination Angle. Inclination angle for
escalator shall be not less than 30 degrees,
but not more than 35 degrees.
Balustrades
8.3.2
Hand Dumbwaiters
7.8.4
a.
a.
kg.
34.0
Exceeding
Loads
Rated
Dumbwaiters having a rated load exceeding
34.0 kg shall be suspended by steel wire
ropes or chains having a factor safety of not
less than 4 1/2.
120
non-perforated
Construction. A rigid,
balustrade shall be provided on each side of
the moving step. The balustrade on the
step side shall have no areas on the step
side shall have no areas or moldings
depressed or raised more than 6.3 mm from
Such areas of
the parents surface.
surfaces
boundary
all
have
moldings shall
CHAPTER 6
-
ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
beveled unless parallel to the direction of
travel.
provided they meet the requirements of Sec.
6.8.3.2 (b).
Balustrades shall be designed to resist the
simultaneous application of a lateral force of
584 N/m and vertical load 730 N/rn, both
applied to the top of the balustrade.
Exception Sec. 6.8.3.2 (e):
Where the
clearance of the upper outside edge of the
balustrade and the ceiling or soffit is more
than 305 mm or where the intersection of
the outside balustrade and the ceiling or
soffit is more than 610 mm from the
centerline of the handrail.
The skirt panel adjacent to the step shall be
constructed of material having a smooth
surface. Embossed, perforated, or roughly
textured materials shall not be used.
f.
Skirt panels shall not deflect more than 1.6
mm under a force of 68 kg applied to any
exposed point between the upper and lower
combplates.
b.
Use of Glass or Plastics in Balustrades.
Glass or plastics, if used in balustrades,
shall conform to the requirements of ANSI
Z97.1, except that there shall be no
requirement for the panel to be transparent.
These devices shall consist of raised objects
fastened to the decks, no closer than 102
mm to the handrail, and spaced no greater
than 183 mm, apart. The height shall be not
less than 19 mm. They shall have no sharp
corners or edges.
Exception Sec. 6.8.3.2 (b):
Plastics
bounded to a basic supporting panel.
8.3.3
c.
d.
e.
Anti-Slide Device. Anti-slide devices shall
be provided on decks or corn binations of
decks when the outer edge of the deck is
greater than 305 mm from the centerline of
the handrail or, on adjacent escalators,
when the distance between the handrails is
greater than 406 mm.
Clearance Between Balustrades and
Steps. The clearance on either side of the
steps between the step tread and the
adjacent skirt panel shall not be more than
4.8 mm.
Handrail
a.
Type Required. Each balustrade shall be
provided with a handrail moving in the same
direction and at substantially the same
speed as the steps.
Change in Width Between Balustrades.
The width between the balustrades in the
direction of travel shall not be changed
abruptly nor by more than 8% of the
greatest width.
b.
Extension Beyond Combplates. Each
moving handrail shall extend at normal
handrail height not less than 305 mm
beyond the line of points of the combplate
teeth at the upper and lowering landings.
In charging from the greater to the smaller
width, the maximum allowable angle of
change in the balustrade shall be 15 deg.
from the line of travel.
c.
Guards. Hand or finger guards shall be
provided at the point where the handrail
enters the balustrade.
d.
Between
Distance
Handrails.
The
horizontal distance between the centerlines
of the two handrails, measured on the
incline, shall not exceed the width between
the balustrades (See Sec. 6.8.3.1) by more
than 152 mm, with a maximum of 76 mm on
either side of the escalator (see Appendix F,
Fig. Fl).
Guards at Intersections. A solid guard
shall be provided in the intersection of the
angle of the outside balustrade (deck board)
and the ceiling of soffit.
The vertical front edge of the guard shall
project at least 356 mm horizontally from the
apex of the angle. The escalator side of the
vertical face of the guard shall be flush with
the face of the well way.
8.3.4
Steps
a.
The exposed edge of the guard shall be
rounded. Guards may be of glass or plastic
121
Material and Type. Step frames shall be
made of non-combustible material.
CHAPTER 6
ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
Where tightening devices are operated by
means of tension weights, provision shall be
made to retain the weights in the truss if they
should be released.
Steps treads shall be horizontal and made
of non-combustible material which will afford
a secure foothold.
Exception: Step tread material may be slow
burning type if covered on the underside
with sheet metal not less than 0.44 mm thick
or with equivalent fire-resistive material.
b.
Dimensions of Steps. The depth of any
step tread in the direction of travel shall be
not less than 400 mm, and the rise between
treads shall be not more than 216 mm. The
width of a step tread shall be not less than
406 mm nor more than 1016 mm. (See
Appendix F, Fig. Fl)
8.3.7
Step Wheel Tracks. Step wheel tracks shall
be designed so as to prevent displacement of
the steps and running gear if a step chain
breaks.
8.3.8
Rated Load
a.
Structural. For the purposes of structural
design, the rated load in kilograms shall be
considered to be not less than:
Structural rated load
c.
d.
Slotting of Step Risers. The step riser shall
be provided with vertical cleats which shall
mesh with slots on the adjacent step tread
as the steps made the transition form incline
to horizontal.
Slotting of Step Treads. The tread surface
of each step shall be slotted in a direction
parallel to the travel of the steps. Each slot
shall be not more than 6.3 mm wide and not
less than 9.5 mm deep; and the distance
from center to center of adjoining slots shall
be not more than 9.5 mm.
b.
b.
=
W
=
length of the horizontal projection of
the entire truss, mm
width of the escalator, mm.
(see Sec. 6.8.3.1)
For the purpose of driving
Machinery.
transmission
and
power
machine
calculations, the rated load in kilograms
shall be considered to be not less than:
B
W
There shall be a
Where Required.
combplate at the entrance and at the exit of
every escalator.
c.
Design of Combplates. The combplate
teeth shall be meshed with and set into the
slots in the tread surface so that the points
of the teeth are always below the upper
surface of the treads.
=
=
=
3.5 WB where:
1.32 x rise, meter
width of the escalator, mm
(see Sec. 6.8.3.1)
Brake. For the purpose of brake
calculations, the rated load in kilograms
shall be not less than:
Brake rated load
B
=
=
4.6 WB where:
1.732 x rise, meter
W = width of the escalator, mm
(see Sec. 6.8.3.1)
Combplates shall be adjustable vertically.
Sections forming the combplate teeth shall
be readily replaceable.
8.3.6
A
Machinery rated load
Combplates
a.
4.6 WA
where:
Slots shall be so located on the step tread
surface as to form a cleat on each side of
the step tread adjacent to the skirt panel.
8.3.5
=
d.
Trusses or Girders. The truss or girder shall
be designed to safely sustain the steps and
running gear in operation. In the event of
failure of the track system it shall retain the
running gear in its guides.
Step. The step shall be designed to support
a load of 136 kg on a 152 mm by 254 mm
plate placed on any part of the step with the
254 mm dimension of step travel.
8.3.10 Design Factors of Safety. The factors of
safety, based on the maximum static loads,
shall e at least the following:
122
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
8.3.11
8.4
8.4.1
a.
Trusses and all supporting structure,
including tracks, shall conform to the AISC
Specifications for Design, Fabrication and
Erection of Structural Steel for Building.
b.
For driving machine parts:
1.
where made of steel or bronze, 8;
2.
where made of cast iron or other
materials, 10.
c.
For power-transmission members, 10.
d.
Forstep, 5.
a.
Starting Switch. Starting switches shall be
of the key-operated type and shall be
located on top or lower landing so that the
escalator steps are within sight.
b.
Emergency Stop Buttons.
Emergency
stop button shall be accessibly located on
the top and lower landing of each escalator
and shall be protected against accidental
operation. The emergency stop button shall
be located in the right hand newel base
facing the escalator at both landings. An
emergency stop button with an unlocked
cover which can be readily lifted or pushed
aside shall be considered accessible. The
operation of either of this buttons shall
interrupt the power to the driving machine.
It shall not be possible to start the driving
machine by these buttons.
c.
Speed Governor. A speed governor shall
be provided, the operation of which will
cause the interruption of power to the driving
machine should the speed of the steps
exceed a pre-determined value, which shall
be not more than 40% above the rated
speed.
Chains. The use of chains with cast iron links
shall not be permitted.
Rated Speed
Limits of Speed. The rated speed shall be
not more than 0.64 m/s except that higher
speeds may be permitted subject to the
approval of the enforcing authority.
8.5 Driving Machine, Motor and Brake
8.5.1
Connection Between Driving Machine and
Main Drive Shaft. The driving machine shall
be connected to the main drive shaft by
toothed gearing, a mechanical coupling, or a
chain.
8.5.2
Driving Motor. An electric motor shall not
drive more than one escalator.
8.5.3
Brake. Each escalator shall be provided with
an electrically released, mechanically-applied
brake capable of stopping the up or down
traveling escalator with any load up to brake
design load. This brake shall be located either
on the driving machine or on the main drive
shaft. Where a chain is used to connect the
driving machine to the main drive shaft, and
an electrically released, mechanically applied
brake is located on the driving machine, a
mechanically applied brake capable of
stopping down a traveling escalator with a
brake design load shall be provided on the
main drive shaft.
8.5.4
Exception [Sec. 6.8.5.4 (c)]:
The overspeed governor is not required where an
alternating current squirrel cage induction
motor is used and the motor is directly
connected to the driving machine.
Note: [Sec. 6.8.5.4 (c), Exception]: The
governor may be omitted in such case even
though a chain is used to connect the
sprocket on the driving machine to the
sprocket on the main drive shaft as
permitted by Sec. 6.8.5.1.
General.
Operating and safety devices
conforming to the requirements of this section
shall be provided.
123
d.
Broken Step-Chain Devices. A broken
step chain device shall be provided, that will
cause the interruption of power to the driving
machine if a step chain breaks, and where
no automatic chain tension device is
provided, if excessive sag occurs in either
step chain.
e.
Application of an Electrically Released
Brake. An electrically released brake shall
automatically stop the escalator when any of
the safety devices required by Sections
6.8.5.4 (b), 6.8.5.4 (c), 6.8.5.4 (d), 6.8.5.4
(f), 6.8.5.4 (h), 6.8.5.4 (i), and 6.8.5.4 (j)
function.
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
f.
g.
in the passenger carrying line of the track
system.
Broken Drive-Chain Device. When the
driving machine is connected to the main
drive shaft by a chain, a device shall be
provided which will cause the application of
the brake on the main drive shaft and also
stop the drive machine if the drive chain
parts.
Tandem operation
m. Tandem Operation.
escalators shall be electrically interlocked
where traffic flow is such that bunching will
occur if the intermediate landing stops.
The interlocks shall stop the escalator
carrying passengers into the common
intermediate landing if the escalator carrying
passengers away from the landing stops.
These escalators shall also be electrically
interlocked to assure that they run in the
same direction.
Stop Switch in Machinery Spaces. A stop
switch, conforming to the requirements of
Sec. 6.4.11.3 (e), shall be provided in each
machinery space where means of access to
the space is provided. This switch, when
opened, shall cause the electric power to be
removed from the escalator driving machine
motor and brake.
Signs. A caution sign shall be located at the
top and bottom landing of each escalator,
readily visible to the boarding passengers.
The sign shall include the following wording:
8.5.5
Machinery
Exception [Sec. 6.8.5.4 (g)J:
spaces in which main line disconnect switch
is located.
h.
Skirt Obstruction Device. Means shall be
provided to cause the opening of the power
circuit to the escalator driving machine
motor and brake should an object become
wedge between the step and the skirt panel
as the step approaches the upper and lower
combplates.
a.
Caution
b.
Hold Handrail
c.
Attend Children
d.
Avoid Slides
The sign shall be standard for all escalators
and shall be identical in format, size, color,
wording and pictorials as shown in Fig. F2
Appendix F.
Rolling Shutter Device. Rolling shutters, if
used, shall be provided with a device which
shall be actuated as the shutter begin to
close to cause the opening of the power
circuit to the escalator driving machine
motor and brake.
j.
The sign shall be durable and have a
maximum thickness of 6.5 mm with rounded
or beveled corners and edges.
Reversal Stop Device. Means shall be
provided to cause the opening of the power
circuit to the driving-machine motor and
brake in case of accidental reversal of travel
while the escalator is operating in the
ascending direction.
Access to Interior. Reasonable access to
the interior of the escalator shall be provided
for inspection and maintenance.
8.5.6
Section 9.0 Moving Walks
k.
Step Demarcation Lights. Green step
demarcation lights located below the step
shall be located at both landing in an area
not to exceed 406 mm from combplate.
There shall be a minimum of two fluorescent
lamp fixtures at each landing. The lamps
shall be activated whenever the escalator is
in operation.
9.1
Step Upthrust Device. Means shall be
provided to cause the opening of the power
circuit to the escalator driving machine
motor and brake should a step be displaced
against the upthrust tract at the lower curve
Design Requirements
9.1.1
Direction of Passage. Passage from a
landing to a treadway or vice versa shall be in
the direction of treadway travel at the point of
passenger entrance or exit.
9.1.2
Load Rating
a.
124
Structural. For the purpose of structural
design, the load rating shall be considered
to be not less than 4.78 kPa of exposed
treadway.
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
b.
9.1.3
Machinery.
For the purpose of brake
treadway,
and
power
transmission
calculations, the load rating shall be
considered to be not less than 3.69 kPa of
exposed treadway.
c.
Width
a.
b.
Limitations. The width of moving walk (the
exposed width of treadway) shall be not less
than 560 mm. The maximum width shall
depend both on the maximum treadway
slope at any point on the treadway, and on
the treadway speed. The width shall not
exceed the value shown in Table 6.9.1.3 (a).
9.1.5 Belt Pallet Type Treadway. Belt pallet type
treadways shall conform to the following:
a.
Factor of Safety. Pallet connecting chains
or other connecting devices between pallets,
and. pallets where part of the propelling
system, shall have a factor of safety of not
less than 10 based on ultimate strength.
b.
Splices. Splicing of the treadway belt shall
be made in such a manner as to result in a
continuous unbroken treadway surface of
the same characteristics as the balance of
the belt.
c.
Grooving. The treadway surface shall be
grooved in direction parallel to its travel for
the purpose of meshing with combplates at
the landings. Each groove shall not be more
than 4.8 mm deep; and the distance from
center to center of adjoining grooves shall
be not more than 12.70 mm slides of
grooves may slope for mold draft purposes
and may be filleted at the bottom.
d.
Alignment. Adjacent ends of pallets shall
not vary in elevation more than 1.6 mm. The
fasteners that attach the belt to the pallets
shall not project above the exposed
treadway surface.
Change in Width. The exposed width of
treadway shall not be decreased in the
direction of travel.
This width requirement applied only to
moving walks having entrance to or exit
from landings. It is not intended to preclude
development of moving walk systems in
which changes in width are made safe and
practical by direct passage from one
treadway to another, subject passage from
one treadway to another, subject to the
approval of the enforcing authority.
Table 6.9.1.3 (a)
Treadway Width
Maximum Movinq Walk Treadway Width, in
Above 90
Above 140
Max.
90 fpm
fpm
to
140
fpm to 180
Treadway
Max.
tpm
fpm
Slope at any
Treadway
Treadway
Treadway
point, deg
Speed
Speed
Speed
0 to 4
Unrestricted
60
40
Above 4 to 8
40
40
40
Above 8 to 12
40
40
Not
permitted
9.1.4
9.1.6
Belt Type Treadway. Belt type treadways
shall conform to the following:
a.
Factor of Safety. Belt type treading shall
be designed with a factor of safety of not
less than 5 based on ultimate strength.
b.
Splices. Splicing of the treadway belt shall
be made in such a manner as to result in a
continuous unbroken treadway surface of
the same characteristics as the balance of
the belt.
125
Grooving. The treadway surface shall be
grooved in a direction parallel to its travel for
the purpose of meshing with combplates at
the landings. Each groove shall be not
more than 6.3 mm wide at the treadway
surface and not less than 4.8 mm deep; and
the distance from center to center of
adjoining grooves shall be not more than 13
mm. Sides of grooves may slope for mold
draft purposes and may be filleted at the
bottom.
Pallet Type Treadway. Pallet type treadways
shall conform to the following:
a.
Factor of Safety. Pallet connecting chains
or other connecting devices between pallets,
and pallets where part of the propelling
system, shall have a factor of safety of not
less than 10 based on ultimate strength.
b.
Grooving. The treadway surface of each
pallet shall be grooved in a direction parallel
to its travel. Each groove shall be not more
than 6.3 mm wide at the treadway surface
and not less than 4.8 mm deep; and the
_______
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
the slider bed shall be reasonably smooth.
It shall be so constructed and it will not
support combustion.
distance from center to center of adjoining
grooves shall be not more than 13 mm.
Sides of the grooves may slope for mold
draft purposes and may be filleted the
bottom.
c.
Intermeshing Pellets. Alternate cleats on
adjacent pallets hsall intermesh so that
there is no continuous transverse gap
between adjacent pallets.
d.
Alignment of Pallet Tread Surfaces.
Adjacent ends of pallets shall not vary in
elevation more than 1.6 mm.
9.1.7
Treadway Slope. The slope of the treadway
shall not exceed 3 degrees within 914 mm of
the entrance and exit and shall not exceed 12
degrees at any point.
9.1.8
Speed. Treadway speed shall conform to the
following:
a.
Maximum Speed. The maximum speed of
a treadway shall depend on the maximum
slope at any point on the treadway. This
speed shall not exceed the value
determined by Table 6.9.1.8 (a).
b.
The maximum speeds
Higher Speeds.
listed in Table 6.9.1.8 (a) apply only to
moving walks having an entrance or exit to
It is not intended to preclude
landings.
development of moving walk systems in
which higher speeds are made safe
practical, subject to the approval of the
enforcing authority.
b.
Where the treadway is
Roller Bed.
supported on a series of rollers, the
combination of roller spacing, belt tension,
and belt stiffness shall be such that the
deflection of the treadway surface, midway
between roller, shall not exceed the quantity
0.239 mm plus 0.004 times the center to
center distance of rollers in millimeter when
measures as follows:
The treadway surface shall be loaded
midway between rollers with a 11.3 kg
weight concentrated on a cylindrical
footpiece 51 mm long by 25 mm in diameter
placed with its long axis across the belt.
Deflection of this footpiece from its unloaded
position shall not exceed the figure obtained
above.
The rollers shall be conventric and true
running within commercially acceptable
tolerances.
c.
Edge Supported Belt. When the treadway
belt is transversely rigid and is supported by
rollers along its edges, the following
requirements shall apply:
1.
With the belt tensioned through the
take-up system, the permissible
slope of a straight line from the top
of a treadway rib adjacent to the
balustrade, in a plane perpendicular
to the path of the treadway shall not
exceed 3% when the treadway is
loaded with a 68 kg weight on a 152
mm by 254 mm plate located on the
centerline of the treadway with 254
mm dimension in the direction of
treadway travel.
2.
In order to support the treadway in
case of localized overload, supports
shall be supplied at intervals, not
exceeding 183 mm along the
The
centerline of the treadway.
supports shall be located at a level
not more than 51 mm below the
underside of the treadway when it is
loaded under the test conditions
prececing
the
by
required
paragraph.
Table 6.9.1.8 (a)
Tread Speed
Maximum Treadway Slope
At any Point onTreadway, deg.
0 to 8
Above 8 to 12
NOTE:
1 radian
rn/s
9.1.9
=
180
140
deg. x 0.01 75
fpmxo.00508
Supports.
following:
a.
Maximum Treadway
Speed, fpm
Support
shall
conform
to the
Slider Bed. The carrying portion of the
treadway shall be supported for its entire
width and length except where it passes
from a support to a pulley. The surface of
126
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
d.
Pallet and Belt Pallet Type. Pallet wheel
tracks shall be so designed and located as
to prevent more than 3.2 mm vertical
displacement of the treadway should the
pallet connection means break.
3.
,
9.1.10 Threshold Plates. The entrance to or exit
from a moving treadway shall be provided with
a threshold plate designed and installed to
provide smooth passage between treadway
and landing and vice versa and it shall
conform to the following:
a.
Type Required. The threshold plate shall
be provided with a comb.
b.
Clearance. The threshold comb teeth shall
be meshed with a set into the grooves in
treadway surface so the points of the teeth
are always below the upper surface of the
treadway.
c.
9.1.11
b.
Geometry.
The height of the balustrade
shall be not less than 838 mm nor more
than 1070 mm from the treadway to the top
of handrail, measured perpendicular to the
treadway surface. The handrail shall be a
minimum of 102 mm horizontally and 25 mm
vertically away from adjacent surfaces. The
center line of the handrail shall be not more
than 254 mm, measured horizontally, from
the vertical plane through the edge of the
exposed treadway (see Appendix F, Fig.
F3).
c.
Clearance with Treadway. If the balustrade
covers the edge of the treadway, the
clearance between the top surface of the
treadway and the underside of the
balustrade shall not exceed 6.3 mm. Where
skirt panels are used, the horizontal
clearance on either side of the treadway
between the treadway and the adjacent skirt
panel shall be not more than 6.3 mm.
Surface. The suiface of the plate shall
afford a secure foothold. The surface shall
be smooth from the point of intersection of
the comb teeth and upper surface of the
treadway, for a distance not exceeding 102
mm and not less than 25 mm.
Balustrades. Moving walks shall be provided
with an enclosed balustrade on each side
conforming to the following:
9.1.12 Guards at Ceiling Intersections.
a.
a.
Construction
1.
2.
Balustrades shall be designed to
resist the simultaneous application
of a lateral force of 584 N/m and a
vertical load of 730 N/rn
both
applied
to
the
top
of the
balustrades.
Balustrades
without
moving
handrails shall be designed so as to
provide no surfaces which can be
gripped by a passenger. On the
treadway side, the balustrade shall
have
no areas
or moldings
depressed or raised more than 6.3
mm from the parent surface. Such
areas or moldings shall have all
boundary surfaces beveled unless
parallel to the direction of travel.
The balustrade shall extend at
normal height not less than 305 mm
beyond the end of the exposed
treadway.
A solid guard shall be provided in the
intersecting angle of the outside balustrade
(deck board) and the ceiling or soffit.
Exceptions:
(1)Where the distance from the face of the
weliway to the centerline of the handrail
is more than 610 mm.
(2) Where the clearance between the face of
the well way and the upper outside edge
of the balustrade is more than 305 mm.
b.
Glass or plastics panels, if used in
the balustrades shall conform to the
requirements of ANSI Z97.1, except
that there shall be no requirement
for the panels to be transparent.
127
The horizontal length of the guard shall be
such that the vertical edge of the guard shall
be at least 191 mm high. The moving walk
side of the vertical face of the guard shall be
flush with the face of the wellway. The
exposed edge of the guard shall be
rounded. Guards may be of glass or plastic
provided they meet the requirements of
Section 6.9.1.11 (a)(2).
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
gravity under any load condition up to and
including the rated load condition up to and
including the rated load with the power
supply interrupted do not require brakes.
9.1.13 Handrails. Handrails shall conform to the
following:
a.
Number Required. Two moving handrails
shall be provided on each moving walk.
c.
Electrically
Application of Brakes.
released brakes specified in Sc. 6.9.1.14 (b)
shall stop the treadway automatically upon
failure of power or when any of the safety
devices specified in Section 6.9.2 operate.
Brakes on the main drive shaft, if not of the
electrically released type, shall be applied
should the drive chain part.
d.
Speed Reducers. Speed reducers shall
meet the requirements for design and
application as established for various types
in the appropriate Gear Manufacturer’s
Practice Standards.
Exception: A single moving handrail may be
used for moving walks having a slope of 3
degrees or less, a speed of (0.36 mIs), or
less and a width of 610 mm or less.
b.
Location. The moving handrail at both the
entrance and exit landings shall extend at
normal height not less than 305 mm beyond
the end of the exposed treadway. The point
at which the moving handrail enters or
leaves an enclosure shall be not more than
254 mm above the floor line.
c.
Handrail Guards. Hand or finger guards
shall be provided at the points where the
handrails enter the enclosures.
d.
Enclosure. The moving handrail return run
and its driving and supporting machinery
shall be fully enclosed.
e.
The loading shall be considered to be
uniform and the service to be 24 hours per
day.
e.
Speed. Each moving handrail shall move in
the same direction and at substantially the
same speed as the treadway.
When operating at the load rating of the
treadway, the load imposed on such chains
shall not exceed the horsepower rating as
established by these standards.
9.1.14 Drive, Motor and Brake
a.
Connection Between Drive and Main
Drive Shaft. The driving machine shall be
connected to the main drive shaft by toothed
gearing, a coupling or a chain.
b.
Brakes Required. Each moving walk shail
be provided with an electrically-released,
mechanically-applied brake capable of
stopping and holding the treadway with any
load up to the load rating. The brake shall
be located on the driving machine, the main
drive shaft, or specially attached braking
surface attached directly to the treadway.
Chain Drives. Chain drives shall be of the
and
types covered by ANSI B29.1
ANSI/SAE SP-68.
The loading shall be considered to be
uniform and the service to be 24 hours per
day.
f.
V-Belt Drives. The load imposed on V-belt
drives, when operating at the load rating of
the treadway, shall not exceed the
horsepower rating as established by
ANSIIRMA IP-20.
The loading shall be considered to be
uniform and the service to be 24 hours per
day.
Where a chain is used to connect the driving
machine to the main drive shaft, a brake
shall be provided on the main drive shaft. It
is not required that this brake be of the
electrically-released type if an electricallyreleased brake is provided on the driving
machine.
g.
Pallet propelling
Other Components.
chains and drive and breaking components
other than those specified shall have a
factor of safety of not less than 10.
supporting
The
Structure.
9.1.15 Supporting
structure for the treadway, balustrades, and
machinery shall conform to the requirements
of the AISC Specification for Design,
Exception [Sec. 6.9.1.14(b)]: Moving walks
which will not run in the down direction by
128
CHAPTER 6- ELEVATORS, DUMBWAITERS, ESCALATORS AND MOVING WALKS
Fabrication and Erection of Structural Steel for
Buildings.
9.2 Operating and Safety
Equipment and Wiring
Devices,
Electrical
9.2.1 Devices Required. Operating and safety
devices shall be provided conforming to the
following requirements:
a.
Starting Switch. Starting switches shall be
of the key-operated type and shall be
located upper or lower landing so that the
exposed treadway is within sight.
b.
Emergency Stop Switches. Emergency
stop buttons or other types of manually
operated switches having red buttons or
handles shall be accessibly located at every
entrance to the exit from a moving walk, and
shall be protected against accidental
operation. The operation of any of these
buttons or switches shall interrupt the power
to the driving machine and to the brake,
where provided. It shall be impossible to
start the driving machine by these buttons or
switches.
c.
d.
where the brake is directly coupled to
the driving machine and where a device
is provided that will cause interruption of
power to the motor and apply the brake
should the belts or chains lose tension
of brake.
Broken Drive-Chain Switch. Where the
driving machine is connected to the main
drive shaft by a chain, and where a brake is
located on the main drive shaft when
required by Sec. 6.9.1.14 (b), a device shall
be provided which will cause application of
the brake should the drive chain part.
e.
Broken Treadway Device for Belt Pallet
Type and Pallet Type. A device shall be
provided which will cause interruption of
power to the driving machine and to the
brake, where provided, if the connecting
means between pallets break.
f.
Power Interruption. Where a device is
required to interrupt power, such interruption
shall not be subject to intentional delay. The
use of a supplemental and independent
device with or without intentional delay is
permissible.
g.
Stop Switch in Machinery Spaces. A stop
switch conforming to the requirements of
Sec. 6.4.11.3 (e) shall be provided in each
machinery space where means of access to
the space is provided. This switch, when
opened, shall cause electrical power to be
removed from the driving machine motor
and brake.
Exception: Machinery space in which the
main line disconnect switch is located.
h.
Speed Governor. Moving walks required
by Sec. 6.9.1.14 (b) to be equipped with a
brake, or which are driven by a direct
current motor, shall be provided with a
speed governor which will cause the
interruption of power to the driving machine
and to the brake, where provided, should
the speed of the treadway exceed a pre
determined speed which shall be not more
than 40% above the maximum designed
treadway speed.
Exceptions [Sec. 6.9.2.1 (d)}:
(1) Moving walks driven by alternating
current induction motors directly coupled
to the driving machine.
(2) Moving walks driven by alternating
current induction motors connected to
the driving machine by belts or chains,
129
Rolling Shutter Device. Rolling shutters if
used, shall be provided with a device which
shall be actuated as the shutters begin to
close to cause the opening of the power
circuit to the moving walk driving machine
motor and brake.
CHAPTER 7— BOILERS AND PRESSURE VESSELS
Chapter 7
BOILERS AND PRESSURE VESSELS
Definitions:
a boiler mounted on a selfLocomotive Boiler
propelled track locomotive and used to furnish
motivating power for traveling on rails. (It does not
include locomotive cranes, tractors, or other selfpropelled apparatus). Locomotive boilers however, if
dismantled from locomotive and reinstalled for
stationary use, are not included in this definition.
—
a closed vessel
Boiler or Steam Generator
intended for use in heating water or for application of
heat to generate steam or other vapor to be used
externally to itself.
—
Coal-Fired Boiler used stokered water temperature
coal or pulverized coal for water-tube.
—
Low Pressure Heating Boiler a boiler operated at a
2 gage steam
pressure not exceeding 1.055 kg/cm
water temperature not exceeding 121°C.
—
a
Condemned Boiler Unfired Pressure Vessel
boiler or unfired pressure vessel that has been
inspected and declared unsafe to operate or
disqualified, stamped and marked indicating its
rejection by qualified inspecting authority.
—
Medium Pressure Heating Boiler a boiler operated
at pressure not exceeding 103.5 MPa gage steam, or
water temperature not exceeding 130°C.
—
Existing Installations any boiler or unfired pressure
vessel constructed, installed, placed in operation but
subject to periodic inspection.
—
Miniature Boiler as used in this Code herein mean
any boiler which does not exceed any of the following
limits: 405 mm inside diameter, 1065 mm overall
2 of water
length of outside of heads at center, 1 .85m
2 maximum allowable
heating surface, 7.03 kg/cm
working pressure.
—
an inspection made on the
External Inspection
external parts, accessories and/or component even
when a boiler or unfired pressure vessel is in
operation.
—
Fire Tube Boiler
inside the tube.
—
New Boiler or Unfired Pressure Vessel Installation
include all boilers and unfired pressure vessels
constructed, installed, placed in operation or
constructed for.
a boiler where heat is applied
—
a process of welding metals in a
Fusion Welding
molten and vaporous state, without the application of
mechanical pressure or blows. Such welding may be
accomplished by the oxy-acetylene or hydrogen flame
or by electric arc. Thermal welding is also classified
as fusion welding.
—
Oil-Fired Boiler uses Bunker C as fuel for heating
boiler and power boiler.
—
an internally fired boiler which is
Portable Boiler
self-contained and primarily intended for temporary
location and the construction and usage is obviously
portable.
—
uses natural gas or liquefied
Gas-Fired Boiler
petroleum gas (LPG) for heating boiler, fire tube or
water-tube type.
—
Heat-Recovery Steam Generator
vessel that uses flue gas heat.
—
a closed vessel in which steam or
Power Boiler
other vapor (to be used externally to itself) is
2
generated at a pressure of more than 1.055 kg/cm
heat.
of
application
direct
by
the
gage
—
unfired pressure
ASME Boiler Construction Code The term, ASME
Boiler Construction Code, shall mean the Boiler
Construction Code of the American Society of
and
amendments
Engineers with
Mechanical
the
by
approved
and
made
interpretations thereto
Society.
Council of the
an inspection made when a
Internal Inspection
boiler or unfired pressure vessel is shut down and
handholes, manholes, or other inspection openings
are opened or removed for inspection of the interior.
—
—
130
CHAPTER 7— BOILERS AND PRESSURE VESSELS
Reinstalled Boiler or Unfired Pressure Vessel
a
boiler or unfired pressure vessel removed from its
original setting and re-erected at the same location or
erected at a location without change of ownership.
permit and other permits necessary should
also be stipulated on the plan.
—
b.
Detailed assembly plan of boiler should
show all appendages indicating instruments,
panels if any for controls and all safety
devices. Details should show actual joints,
riveting, welding, thickness of plates, tubes,
fusible plugs etc.
Steam conditions like
temperature, pressure, degrees superheat
should be indicated.
c.
Piping drawing, preferably in isometric
drawing showing elevations headers, leads
to headers preferably from the bottom,
branches from headers, preferably from the
top, expansion joints, pipes covering sizes,
fittings and valves and method support.
d.
All plans and specification should be
prepared
under
supervision
of
a
Professional Mechanical Engineer and
should have his signature and seal on every
page, regardless of boiler horsepower.
Second Hand Boiler or Unfired Pressure Vessel
as used herein shall mean a boiler or unfired pressure
vessel of which both the location and ownership have
been changed after primary use.
—
Steam System
comprises steam generation,
distribution, and utilization. It includes fuel, combustion
air, feedwater, combustion system, steam quality and
efficiency.
—
Unfired Pressure Vessel
a vessel in which
pressure is obtained from an external source, or from
an indirect application of heat.
—
Waste-Heat Boiler
unfired pressure vessel that
uses flue gas heat from waste incinerator.
—
Water Tube Boiler
outside the tube.
—
a boiler where heat is applied
Section 1.0 General Requirements for
Boilers and Pressure Vessel Installation
1.1
1.2
Steam boilers should preferably be located.
Installation and Operating Permits
Application for permits to install and operate
steam generators for power or heat, unfired
pressure vessels for steam, air or gases shall be
secured from the place or locality of installation.
For municipalities, permits shall be secured from
the office of the Municipal/City Engineer or
Building Official, if available, or from the
Regional Office of the Department of Labor and
Employment.
A similar permit to install and
operate pollution sources equipment shall also
be secured from the regional offices of the
Department of Environment and Natural
Resources. For sample application forms, see
back pages.
Application forms shall be
accompanied by plans and specifications in
quadruplicate showing:
a.
Locations
1.3
General Layout giving a plan view,
longitudinal view and at least a front view
showing location of boiler with respect to
building, location, size and height of smoke
stack, location of steam generator auxiliaries
and location and size of fuel supply.
Building permit and location plan of the
same, Electrical permit, Fire Department
131
a.
In detached buildings of fire resistant
construction used for no other purpose and
situated not less than 3 m distance from
buildings not forming part of factory, or in
structures of fire resisting materials,
preferably
stone
or
concrete
walls
connected to or in close proximity to other
factory buildings.
b.
No part of the steam boiler should be closer
than one meter from any wall.
c.
In case of firetube boilers, sufficient room for
tube removal either thru the front or rear
should be provided.
Steam Boiler Rooms
a.
Although not to be used for passage, boiler
rooms should be provided with two doors
preferably on opposite ends or sides which if
locked may be opened without key from the
inside.
b.
As the room air is usually the source of
combustion air, sufficient ventilation from
outside should be provided.
CHAPTER 7— BOILERS AND PRESSURE VESSELS
c.
1.4
1.5
1.6
1.7
Where brickwork is necessary, the surface
facing the hot gases should be fired brick and
the outside may be red brick or other suitable
material.
c.
No smokestack should be closer than 305
mm from any exposed woodwork or framing.
a.
Brickwork should be provided with sufficient
both vertically and
expansion joints
horizontally to take care of expansion at
operating temperature.
d.
Where two or more steam boilers will be
connected in parallel, each steam outlet
should be provided with a non-return valve
and a shut off valve.
b.
Insulating castables is used for medium
pressure boiler.
e.
for
sufficient
pressure
steam
Only
requirements should be allowed. No high
pressure will be generated just to be
reduced on the line to suit requirements.
f.
All construction features of boiler should be
in conformity with the ASME Boiler
Construction Code when available or its
equivalent. (JIS, ASTM, ISO Standards).
g.
All boiler installations, including reinstalled
boilers, shall be installed in accordance with
the requirements of the latest revision of the
A.S.M.E. Boiler Construction Code and/or
Rules and Regulations provided herein.
h.
Ladders and Catwalks. A steel catwalk or
platform at least 455 mm wide and provided
with standard handrails and toe-board on
either side shall be installed across the tops
of adjacent boilers or at some other
convenient level for the purpose of affording
safe access to the boilers. All catwalks shall
have at least two means of exit, each exit to
be remotely located from the other, and
connected to a permanent stairway or
inclined ladder leading to the floor level.
No structural stress other than its own weight
should be imposed on any brickwork and in no
case should the full weight or part weight of
steam boiler or its appurtenances be supported
on brickwork.
No steam boiler should be enclosed or walled-in
by
inspection
and
without authorization
authorized government representative and who
will conduct a hydrostatic test of 130% of
stipulated working pressure.
Ceiling Clearance
a.
1.8
supporting or guyed to withstand a wind
load 160 kph and rise at least 5,000 mm
above the eaves of any building within a
radius of 50 meters. However, in lieu of the
said height requirement, a system should be
so designed and constructed to eliminate
smoke nuisance to the neighboring
structures.
Steam boilers should be mounted over a
suitable foundation or concrete pad of not
less than 305 mm thick and with sufficient
area at base to be supported by the bearing
capacity of the soil with a safety factor of not
less than four (4).
When boilers are replaced or new boilers
are installed in either existing or new
buildings, a minimum height of at lest 2,130
mm shall be provided between the top of the
boiler proper and the ceiling except in single
installation of self-contained boilers where a
minimum height of at least 915 mm shall be
provided between the highest point of any
valve stem or fitting and the ceiling.
Other Requirements
a.
b.
Section 2.0 Specific Requirements for
Fired Tube Boilers
All boilers and unfired pressure vessels shall
be so located that adequate space will be
provided for the proper operation of the
boiler and its appurtenances, for the
inspection of all surfaces, tubes, water walls,
economizers, piping, valves and other
necessary
their
for
and
equipment
maintenance and repair.
Smokestacks
capacity to
should be
handle flue
2.1
of sufficient
gases, self-
132
Maximum Allowable Working Pressure. The
maximum allowable working pressure on the
shell of a boiler or drum shall be determined by
the strength of the weakest SECTION OF THE
STRUCTURE, computed from the thickness of
the plate, the tensile strength of the plate, the
efficiency of the longitudinal joint, OR TUBE
LIGAMENTS, the inside diameter of the outside
course and the factor of safety by these rules.
CHAPTER 7- BOILERS AND PRESSURE VESSELS
TS x t x E
=
R x ES
removed from its existing setting, it shall not
be reinstalled for pressure in excess of 1.05
2 gage.
kg/cm
Maximum allowable working
pressure in MPa
where:
TS
=
ultimate tensile strength of shell plate,
2
N/mm
t
=
minimum thickness of shell plate, in
weakest course in mm.
Minimum thickness for Boilerplate
shall be 6.35 mm.
2.4
Age Limit of Fire Tube Boilers
For fusion welding, E shall be taken as equal to
90% or E shall be determined by the following
Philippine Mechanical Engineering Code. For
seamless construction, Eshall be 100%.
R
a.
FS
=
=
=
efficiency of longitudinal joint
one-half the inside diameter of the
weakest course of shell or drum in
mm.
Welded Boilers
Boilers having either longitudinal
or
circumferential seams or fusion welded
construction shall be constructed and
stamped in accordance with the rules and
regulations of the ASME Boiler Construction
Code.
Allowable factor of safety; the ratio of
ultimate strength to allowed stress.
For new construction, FS = 5.
Allowable Stresses
b.
a.
b.
Pressure on Old Boilers
Tensile Strength
In no case shall the maximum allowable
working pressure of an old boiler be
increased to a greater pressure than would
be allowed for a new boiler of same
construction.
When the tensile strength of steel or
wrought iron shell plates is not known, it
shall be taken as 379.31 N/mm
2 for steel
and 310.04 N/mm
2 for wrought iron.
Crushing Strength of Mild Steel
c.
The resistance to crushing of mild steel shall
be taken at 655.17 N/mm of cross sectional
area.
2.3
Reinstalled or second-hand boilers shall
have a minimum factor of safety of 6 when
the longitudinal seams are of lap riveted
construction and a minimum factor of safety
of 5 when the longitudinal seams are of butt
and double strap construction.
The age limit of a horizontal return tubular, flue
or cylinder boiler having a longitudinal lap joint
and operating at a pressure in excess of 0.345
MPa or 3.45 Bar gage shall be thirty years (30
years). A reasonable time for replacement shall
be given at the discretion of the Inspector not to
exceed one (1) year.
E
2.2
c.
Safety Valves
1.
The use of weighted-lever safety
valves shall be prohibited and direct
spring-loaded pop type valves shall
replace these valves.
2.
Safety valves having either the seat
or disc of cast iron shall not be
used.
3.
Each boiler shall have at least one
safety valve and if it has more than
46.5 m
2 of water heating surface or
the generating capacity exceeds
910 kg/hr, it shall have two (2) or
more safety valves.
Factor of Safety
a.
b.
The Professional Mechanical Engineer shall
increase the following factors of safety shall
be increased if the condition and safety of
the boilers demand it.
The lowest factor of safety permissible on
existing installations shall be 4.5 except for
horizontal return tubular boilers having
continuous lap seams more than 3,650 mm
in length where the factor of safety shall be
9, and when this latter type of boiler is
133
CHAPTER 7— BOILERS AND PRESSURE VESSELS
4.
5.
6.
7.
8.
equipped with safety valves of
sufficient capacity to prevent over
pressure considering the generating
capacity of other boilers.
The valve or valves shall be
connected direct to the boiler,
independent of any other steam
connection, and attached as close
as possible to the boiler, without
necessary intervening pipe or
fittings. When alternation is required
to conform to this rule and
regulation, owners or users shall be
allowed one (1) year in which to
complete the work.
9.
The relieving capacity of the safety
valves on any boiler shall be
checked by any one of the three
following methods and if found to be
insufficient, additional valves shall
be provided.
9.1 By making the accumulation
test, which consists of
shutting off all other steamdischarge outlets from the
boiler and forcing the fires
The
to the maximum.
safety valve capacity shall
be sufficient to prevent a
pressure in excess of 6
the
above
percent
maximum allowable working
pressure.
No valve of any description shall be
placed between the safety valve
and the boiler nor on the vent-out
pipe (if used) between the safety
valve and the atmosphere. When a
vent-out pipe is used, it shall be
sufficiently sized and fitted with an
open drain to prevent water lodging
in the upper part of the safety valve
or escape pipe. When an elbow is
placed on a safety valve outlet or
vent-out pipe shall be securely
anchored and supported. All safety
valve discharges shall be so located
or piped as to be carried clear from
walkways or platform used to
control the main stop valves of
bilers or steam headers.
9.2 By measuring the maximum
amount of fuel that can be
burned and computing the
corresponding evaporative
capacity (steam generating
capacity) upon the basis of
the heating value of this
These computations
fuel.
shall be made as outlined in
the appendix of the ASME
Boiler Construction Code.
The safety valve capacity of each
boiler shall be such that the safety
valve or valves will discharge all the
steam that can be generated by the
boiler without allowing the pressure
to rise more than 6% above the
highest pressure to which any valve
is set, and in no case to more than
6% above maximum allowable
working pressure.
the
determining
9.3 By
evaporative
maximum
capacity by measuring the
feed water. When either of
the methods outlined in (b)
is employed, the sum of the
safety valve capacities shall
be equal to or greater than
the maximum evaporative
capacity (maximum steam
generating capacity) of the
boiler.
One or more safety valves on every
boiler shall be set at or below the
working
allowable
maximum
valves
remaining
The
pressure.
may be set within 3 to 5 percent
above the maximum allowable
working pressure, but the highest
setting shall not exceed 10% of the
highest pressure to which any valve
is set.
When two or more boilers operating
at different pressures and safety
valve settings are interconnected,
the lower pressure boilers or
interconnected piping shall be
2.5
Feedwater System
a.
134
All boilers shall have a feedwater supply
system which will permit feeding of the
boilers at any time while under pressure.
CHAPTER 7— BOILERS AND PRESSURE VESSELS
b.
A boiler having more than 46.5 m
2 of water
heating surface shall have at least two
means of feeding, one of which shall be an
approved feed pump or injector. Where a
source of feed directly from pressure mains
is available at sufficient pressure to feed the
boiler against a pressure 6 percent greater
than the release pressure of the safety valve
with the highest release setting, this may be
considered one of the means.
c.
The feed piping to the boiler shall be
provided with two check valves near the
boiler and a valve near the pump. When
two or more boilers are fed from a common
source, there shall also be a valve on the
branch to each boiler between the check
vale and the boiler. When two or more
boilers are fed from a common source, there
shall also be a valve on the branch to each
boiler between the check valve and source
supply. Whenever a globe valve is used on
feed piping, the inlet shall be under the disc
of the valve.
d.
2.6
Where
deaerating
heaters
are
not
employed, it is recommended that the
temperature of the feedwater be not less
than 102°C to avoid the possibility of setting
up localized stress.
Where deaerating
heaters are employed, it is recommended
that the minimum feedwater temperature be
not less than 197°C so that dissolved gases
may be thoroughly released.
Gages and Gage Connections
Boilers
—
Fire Tube
a.
Each boiler shall have three or more gage
cocks, located within the range of the visible
length of the water glass, except when such
boiler has two water glasses with
independent connections to the boiler,
located on the same horizontal line and not
less than 610 mm apart.
b.
For all installations where the water gage
glass or glasses are more than 9,000 mm
from the boiler operating floor, it is
recommended that water level indicating or
recording gages be installed at eye height
from the operating floor.
Each steam boiler shall have steam gage,
with dial range not less than one and onehalf (11/2) times and not more than twice the
maximum allowable working pressure,
connected to the steam space or to the
c.
steam connection to the water column. The
steam gage shall be connected to a siphon
or equivalent device of sufficient capacity to
keep the gage tube filled with water and so
arranged that the gage cannot be shut off
from the boiler except by a cock placed near
the gage and provided with a tee or level
handle arranged to be parallel to the pipe in
which it is located when the cock is open.
2.7
d.
When a steam gage connection longer than
2,440 mm becomes necessary, a shut off
valve may be used provided the boiler is of
the outside screw and yoke type and is
locked open. The line shall be ample size
with provision for free blowing.
e.
Each boiler shall be provided with a 6.35
mm nipple and globe valve connected to the
steam space for the exclusive purpose of
attaching a test gage when the boiler is in
service so that the accuracy of the boiler
steam gage may be ascertained.
f.
Each stem outlet from a boiler (except
safety valve connections) shall be fitted with
a stop valve located as close as practicable
to the boiler.
g.
When a stop valve is so located that water
can accumulate, ample drains shall be
provided. The drainage shall be piped to a
safe location and shall not be discharged on
the top of the boiler or its setting.
h.
When boilers provided with manholes are
connected to a common steam line, the
steam connection from each boiler shall be
fitted with two stop valves having an ample
free flow drain between them.
The
discharge of this drain shall be visible to the
operator while manipulating the valves and
shall be piped clear of the boiler setting.
The stop valves shall consist preferably of
one automatic non-return valve and a
second valve of the outside-screw and yoke
type.
Blow Off Connections
a.
135
—
Fire Tube Boiler
The construction of the setting around each
blow-off pipe shall permit of free expansion
and contraction. Careful attention shall be
given to the problem of sealing these setting
openings without restricting the movement
of the blow-off piping.
CHAPTER 7— BOILERS AND PRESSURE VESSELS
b.
c.
d.
e.
Fire brick or other resisting materials, so
constructed, shall protect all blow-off piping,
when exposed to furnace heat, that the
piping may be readily inspected.
3.2
Existing Installations
a.
Each boiler shall have a blow-off pipe, fitted
with a valve or cock, in direct connection
with the lowest water space. Cocks shall be
of the gland or guard type and suitable for
the pressure allowed. The use of globe
valves shall not be permitted. When the
maximum allowable working pressure
2 gage, each blow-off
exceeds 7.00 kg/cm
pipe shall be provided with two valves or a
valve and cock, such valves and cocks to be
of the extra heavy type.
3.3
All fittings between the boiler and blow-off
valve shall be steel or extra heavy fittings or
malleable iron. In case of renewal of blowoff pipe or fittings, they shall be installed in
accordance with the rules and regulations
for new installations.
Rules and Regulations, as adopted for
Power Boilers applying to strength of
materials and calculations to determine
maximum allowable working pressure, shall
be used for Miniature Boilers unless a
special rule is stated herein.
General Requirements
a.
Maximum Allowable Working Pressure.
The maximum allowable working pressure
on the shell of a boiler or drum shall be
determined by this Code.
b.
Construction. The construction of miniature
boilers including Factor of Safety, except
where otherwise specified, shall conform to
that required for power boilers.
c.
Safety Valves
1.
When the maximum allowable working
2 gage, blow
pressure exceeds 7.00 kg/cm
heavy from the
extra
be
off piping shall
and shall be
valves,
or
valve
the
boiler to
run full size without the use of reducers or
bushings. The piping shall be extra heavy
wrought iron or steel and shall not be
galvanized.
f.
Whenever repairs are made to fittings or
appurtenances or it becomes necessary to
replace them, the work shall comply with the
code for new installations.
g.
All cases not specifically covered by these
rules and regulations shall be treated as
New Installations or may be referred to the
instructions
for
agency
government
.
requirements
the
concerning
The safety valve relieving capacity
of each boiler shall be such that it
will discharge all the steam that can
be generated by the boiler without
allowing the pressure to rise more
than six (6) percent above the
working
allowable
maximum
pressure.
2.
Section 3.0 Specific Requirements for
Miniature Boilers
3.1
New Boiler Installations
a.
Each miniature boiler shall be
equipped with a sealed, springloaded pop type safety valve not
less than 12.7 mm pipe size,
connected directly to the boiler.
No Miniature Boiler, except reinstalled
boilers and those exempted by these Rules
and Regulations, shall hereafter be installed
unless it has been constructed! inspected
and stamped in conformity with ASME Boiler
Construction Code and is approved,
registered and inspected in accordance with
these Rules and Regulations.
d.
Water Gage Glass
1.
136
In those cases where the boiler is
supplied with feedwater directly
from a pressure main or system
without the use of a mechanical
feeding device, the safety valve
shall be set to release at a pressure
not in excess of ninety-four (94)
percent of the lowest pressure
obtained in the supply main or
system feeding the boiler. Return
traps shall not be considered
mechanical feeding devices.
Each miniature boiler shall be
equipped with water gage glass for
the determination of water level.
CHAPTER 7— BOILERS AND PRESSURE VESSELS
2.
3.
e.
The lowest permissible water level
shall be at a point one-third (1/3) of
the height of the shell, except where
the boiler is equipped with internal
furnace, in which case it shall be not
less than one-third of the tube
length above the top of the furnace.
where the boiler is operated without
extraction of steam (closed system).
4.
For small boilers where there is
insufficient space for the usual type
of gage glass, water level indicators
of the glass bull’s eye type may be
used.
f.
Blow-Off Connection
1.
Each miniature boiler shall be
provided with a blow-off connection,
not less than 12.7 mm iron size, in
direct connection with the lowest
water space.
2.
Blow-off piping shall
not be
galvanized and shall be provided
with a valve or cock.
Feedwater Connection
1.
Every miniature boiler shall be
provided with at least one feed
pump or other mechanical feeding
device except where the following
conditions exist:
a)
Where the boiler is connected to
a water main or system having
sufficient pressure to feed the
boiler at any time while under
pressure.
b)
Where the fuel burned is such
that all heat input can be
discontinued instantaneously by
the operation of a valve, cock,
or switch, thereby permitting the
boiler pressure to be quickly
lowered to a point where water
can be introduced from the
connection to the water main.
c)
g.
Each miniature boiler shall be fitted
with a feedwater connection which
shall not be less than 12.7 mm iron
pipe size. The feed piping shall be
provided with a check valve near
the boiler and a valve or check
between the check valve boiler.
3.
Feedwater may be
through the blow-off
Steam Gage
Each miniature boiler shall be equipped with
a steam gage having a dial range not less
than one and one-half (11/2) times and not
more than twice the maximum allowable
working pressure.
The gage shall be
connected to the steam space or to the
steam connection to the gage glass by a
brass or bronze composition siphon tube, or
equivalent device that will keep the gage
tube filled with water.
h.
Where the boiler is operated
without extraction of steam
(closed system) in which case
the boiler is filled, when cold,
through the connections or
opening provided in accordance
with the following rule.
2.
Feedwater shall not be introduced
through the water column or gage
glass connections while the boiler is
under pressure.
The steam piping from a miniature shall be
provided with a stop valve located as close
to the boiler shell or drum as is practicable,
except in those cases where the boiler and
steam receiver are operated as closed
system.
For installations which are gas-fired, the
burners used shall conform to the
requirements
of the
American
Gas
Association, as stated in the ASME Boiler
Construction Code.
j.
introduced
connection
137
Each gas-fired boiler shall be equipped with
a 100 mm vent pipe or flue extended to an
approved location outside the building or
connected to a chimney flue. Where the
horizontal run is more than 3,050 mm the
vent shall be increased to 152 mm. A draft
hood approved design shall be provided on
each boiler.
CHAPTER 7— BOILERS AND PRESSURE VESSELS
The valves shall be set to relieve at or below
the maximum allowable working pressure of
the boiler and so arranged that they cannot
be reset to relieve at a higher pressure of
the boiler.
Section 4.0 Specific Requirements for
Low-Pressure Heating Boilers
4.1
New Installation
a.
b.
42
No Heating Boiler, except re-installed boilers
and those exempted by these Rules and
Regulations, shall hereafter be installed
unless it has been constructed, inspected
and stamped in conformity with ASME Boiler
Construction Code or its equivalent and is
approved, registered and inspected in
accordance with the requirements of these
Rules and Regulations.
Each relief valve shall have a substantial
device which will positively lift the disc from
its seat at least 1.5 mm when there is no
pressure on the boiler.
c.
Each steam boiler shall have a steam
pressure gage connected to the steam
space near the boiler itself. The ranges of
the steam gage shall not be less than 1.0
bar nor more than 2.0 bars.
All new installation boilers, including re
installed boilers, must be installed in
accordance with the requirements of the
latest revision of the ASME Boiler
Construction Code or its equivalent and
these Rules and Regulations.
d.
If in the judgment of the Engineer based on the
following and other requirements, a steam
heating boiler is unsafe for operation at the
pressure previously approved, the pressure
shall be reduced, proper repair made or the
boiler retired from service.
Safety Valves
Each steam boiler shall have two or more
gage cocks located within the visible length
of the water gage glass; except when such
boiler is provided with two water gage
glasses.
Each steam heating boiler shall be provided
with one or more safety valves with a total
2 for each 0.465
area of not less than 25.4m
if grates are
equivalent,
or
area,
grate
of
2
m
not used. It is further provided that the
steam relieving capacity of the safety valve
or valves on any boiler shall be sufficient to
prevent a boiler pressure greater than 1.4
. If there is any doubt as to the
2
kg/cm
an
valve,
safety
the
of
capacity
run.
be
shall
test
accumulation
e.
Stop Valves and Check Valves
If a boiler may be closed off from the heating
system by closing a steam stop valve, there
shall be a check valve in the condensate
return line between the boiler and the
system.
No stop valve of any description shall be
located between a boiler and its safety
valve; nor in the safety valve discharge pipe.
The safety valve may be located on a main
steam pipe connection at the boiler.
b.
Water Gage Glass and Gage Cocks
Each steam boiler shall have at least one
water gage glass with the lowest visible part
above the heating surfaces in primary
When, in the
combustion chamber.
the heating
Engineer,
of
an
judgment
surfaces above the low water line may be
injured by contact with gases of high
temperature, the water gage shall be raised
until the lowest visible part of the gage glass
is above such heating surface.
General Requirements
a.
Steam Gage
If any part of heating system may be closed
off from the remainder of the system by
closing a steam stop valve, there shall be
a check valve in the condensate return pipe
from that part of the system.
Water Relief Valves
f.
Each Hot Water Heating or Hot Water
Supply boiler shall have one or more relief
valves of the spring-loaded type without disc
guides on the pressure side of the valve.
Feedwater Connection
be
shall
connections
Feedwater
independent of any water gage connection
138
CHAPTER 7
BOILERS AND PRESSURE VESSELS
and be made to the condensate return pipe
or reservoir of the condensate return pump.
There should be a stop valve and a check
valve in the feedwater line at the boiler.
g.
Rupture discs or safety heads may be used
for additional protection of pressure vessels.
5.2
Return Pump
Existing Installations
a.
Maximum Allowable Working Pressure
Each condensate return pump where
practicable shall be provided with an
automatic water level control set to maintain
the water level within the limits of two gage
cocks.
h.
1.
Repairs and Renewal of Fittings and
Appurtenances
Whenever repairs are made to fittings or
appurtenances or it becomes necessary to
replace them, the work must comply with the
Code for New Installations.
For Internal Pressure
The
maximum
allowable
working
pressure on the shell of a pressure
vessel shall be determined by the
strength of the weakest course
computed from the thickness of the
plate, the tensile strength of the
plate,
the
efficiency
of
the
longitudinal joint, the inside radius of
the course and the factor of safety
by those rules.
—
TS x t x E
=
Section 5.0 Unfired Pressure Vessels
Test and Inspection
5.1
R x FS
TS
New Installations
=
Maximum allowable working
pressure in MPa
Ultimate tensile strength of shell
plate,
2
N/mm
When the
tensile strength is not known it
shall be taken as 310.34 N/mm
2
for temperatures not exceeding
371°C.
.
a.
Requirements
No
Unfired
Pressure Vessel except
reinstalled vessels and those exempt by the
Rules and Regulations, shall hereafter be
installed unless it has been constructed,
inspected and stamped in conformity with
ASME Unfired Pressure Vessel Boiler
Construction Code and is approved,
registered and inspected in accordance with
the requirements of these Rules and
Regulations.
b.
c.
t
E
=
Efficiency of longitudinal joint
depending upon construction.
Use values as follows:
For fusion welded joints
All new installations unfired pressure
vessels,
including
reinstalled
unfired
pressure vessels shall be installed in
accordance with the requirements of the
latest revision of the ASME Unfired
Pressure Vessel Boiler Construction Code,
and these Rules and Regulations.
Single lap weld
Double lap weld
Single butt weld
Double butt weld
Forge weld
Brazed steel
Brazed copper
Inspections
R
Upon completion of the installation, all
unfired pressure vessels shall be inspected
by the representative authorized by the
government agency concerned.
d.
Minimum thickness of shell plate
of weakest course, mm.
Rupture Discs
139
=
40%
60%
50%
70%
70%
80%
90%
Inside radius of weakest course
of shell, mm, provided the
thickness does not exceed ten
(10) percent of the radius. If the
thickness is over ten (10)
percent of the radius, the outer
radius shall be used.
CHAPTER 7— BOILERS AND PRESSURE VESSELS
FS
2.
by
Authorized Inspector and should not be
considered as supplanting or superseding the
mandatory inspections made by the Authorized
Inspector.
The maximum allowable working
pressure for cylindrical vessels
subjected to external or collapsing
pressure shall be determined by the
rules of the ASME Unfired Boiler
Construction Code.
If required by the jurisdiction before a boiler is
put into operation for the first time, it should be
inspected by the Authorized Inspector. If such
an inspection is not required, the boiler should
be inspected by the plant inspector. In addition
to determining that all equipment is furnished
and installed in accordance with the jurisdiction,
the Code, and the plant specification, all controls
should be tested by a person familiar with the
control system. As opposed to inspection during
manufacture, which pertains to conforming to
Code requirements, this inspection will be
concerned with ensuring that the boiler
supports, piping arrangements, safety devices,
water columns, gage cocks, thermometers,
controls, and other apparatus on the boiler meet
jurisdictional requirements and are adequate for
operation in the system or process in which the
steam is to be used.
=
Factor of safety allowed
those rules.
For external pressure
Section 6.0 Boiler Inspection
6.1
Scope
All boilers and unfired pressure vessels, whether
locally manufactured or manufactured outside
the country, shall undergo hydrostatic tests
before installation. All others unless otherwise
exempted by these Rules and Regulations, and
which are subject to annual inspections as
provided for in this code shall be prepared for
such inspections, or hydrostatic tests whenever
necessary, by the owner or user when notified
by the authorized representative of the
government agency. It is important that
and
complete,
thorough,
be
inspection
accomplished as outlined in this section by both
the Authorized Inspector and plant inspector as
defined in (a) and (b) below.
a.
b.
6.2
Boilers that have been on cold standby or out of
service for a prolonged period should be
carefully inspected internally and externally for
corrosion and for operability of accessories,
safety devices, and controls prior to placing the
boiler in service.
6.3
All reference to Authorized Inspector
throughout this section mean the Authorized
Inspector, who is an Inspector employed by
a city or municipality in the Philippines.
licensed
be
shall
Inspectors
These
Mechanical Engineers for boilers below 350
hp and Licensed Professional Mechanical
Engineers for boilers 350 hp and above.
6.3.1
Preparation for Inspection
General
Where soot blowers are installed, they should
be operated before reducing the boiler load to
50% of normal rating to clean external
surlaces for inspection. It is not advisable to
operate soot blowers after extinguishing fires
due to explosion hazard.
The plant inspector should be an individual
who is a Licensed Mechanical Engineer
knowledgeable and experienced either with
the construction, operation, inspection, and
maintenance procedures for power boilers.
He should be designated by the plant
manager.
All fires should be extinguished. The fuel
supply lines should be shut-off and locked
where feasible. Where oil is used, atomizers
should be removed from oil burners. Where
gas is used and the supply line does not have
a double block and bleed (two shut-off valves
with a vent to atmosphere between them), the
supply line should be blanked off and a
section of the pipe removed between the gas
shut-off valve and burner.
Inspection Frequency
Similar inspections should be made by the
person responsible for the boiler plant as a
whole or by his duly authorized representative
who is hereafter termed Quality Assurance
Engineer or Plant Inspector. Such inspections
should be supplementary to those made by the
The boiler and furnace must be cooled
sufficiently before draining to prevent damage
to the boiler and to prevent the baking of
140
CHAPTER 7— BOILERS AND PRESSURE VESSELS
internal deposits that may be present on the
heating surface. It is recommended that the
boiler be drained while there is sufficient heat
present t dry out interior of the boiler when
ventilated by opening manhole and handhole
covers.
Before opening all manhole and selected
handhole covers, wash out plugs and water
connections, the non-return and steam stop
valves should be closed, tagged, and
preferably padlocked, and the drain valves or
cocks between the two valves should be
opened. The feed and check valves should be
closed, tagged, and preferably padlocked shut
with any drain valves or cocks located
between these two valves opened. After
draining the boiler, the blowoff valves should
be closed and padlocked. Blowoff lines, where
practical, should be disconnected between
pressure parts and valves.
6.3.3
Fire Side
The walls, baffles, tubes, tubesheets, shells,
and drums should be cleaned of ash and soot
to give the plant inspector an opportunity to
examine all parts thoroughly. Brickwork should
be removed as required by the plant inspector
in order to determine the condition of the
furnace, supports, or other parts. It is not
necessary to remove insulation material,
masonry, or fixed parts of the boiler unless
defects or deterioration are suspected. Where
there is moisture or vapor showing through the
covering, the covering should be removed and
a complete investigation made.
6.3.4
External Surfaces and Parts
The external inspection will not require any
particular preparation other than giving the
plant inspector convenient access to the
generating unit and its connections.
The plant inspector should enter the boiler to
make a personal examination of conditions,
but before entering he should first make sure
that it has been properly ventilated and
isolated from active systems. Where possible
portable lamps of 12V or less with current
supplied from transformers or batteries should
be used. Only approved, properly guarded
extension cords with waterproof fittings should
be used, and all connections should be made
external to the boiler. Light fixtures should be
equipped
with
explosion-proof
guards.
Sockets, light guards and fittings should be
properly grounded. Where it is necessary to
use higher voltage supplies, all sockets,
guards, and fittings should be properly
grounded and the circuit provided with
appropriate ground fault service interrupters.
Equipment should be suitable for use in the
boiler or furnace to prevent explosion and
ignition of combustible materials (coal dust,
soot, oil, etc.) and electrical shock.
6.3.2
make sure that the drum has been properly
ventilated.
All external inspections by the plant inspector
should include the examination of the boiler,
its appurtenances, and connections while the
boiler is in service. This inspection is made
primarily
to
observe
operation
and
maintenance of safety devices and operating
procedures.
6.3.5
Inspection of Internal Surfaces and Parts
6.3.6
All Boilers
The internal inspection of the boiler by the
plant inspector should include the examination
of the physical structure with a view to
determining its adequacy for service. The
inspection should cover the condition of the
entire boiler, which may include drum,
waterwalls,
superheater,
reheater,
and
economizer with their fittings, as well as steam
and water connections with their fittings and
valves. The inspection should particularly
include a reexamination of defects and
previous repairs recorded on past inspection
reports.
Water Side
The water surfaces of drums and tubes should
be preferably not be cleaned, unless
otherwise agreed, until after the plant
inspector has a chance to observe the
conditions.
After the drums, tubes, and other pressure
parts have been inspected for deposits and
scale, all these surfaces should be cleaned
internally either by washing, by mechanical
means, or by chemical methods as necessary
The plant inspector should enter the drum of
the boiler to make a personal examination of
conditions, but before entering he should first
141
CHAPTER 7— BOILERS AND PRESSURE VESSELS
for
to provide a clean metal surface
inspection by the plant inspector. After
cleaning, all loose scale and accumulated
deposits should be removed from the boiler
and other pressure parts. Brickwork and
refractory materials should be dried out
carefully when firing up.
6.3.8
The plant inspector should note any erosion,
corrosion, or cracking of stays and braces.
Particular inspection should be made of any
welded stays or braces. All stays, whether
diagonal or through, should be examined to
see if they are in even tension. All fastened
ends should be inspected to note if cracks
exist where the plate is punched or drilled. If
stays are not found in proper tension,
corrective action is recommended. The plant
inspector should test staybolts by tapping one
end of each bolt with a hammer, and when
practical, a hammer or other heavy tool should
be held at the opposite end by an assistant to
make the test more effective.
The plant inspector should examine all internal
surfaces of the exposed metal to observe any
detrimental action caused by water treatment,
scale solvents, oil, or other substances that
may have entered the boiler. The upper half of
the drums in the steam space should be
inspected, particularly for signs of grease, oil,
or similar deposits. Any evidence of oil should
be taken to prevent the entrance of any
additional oil into the boiler. Oil or scale
deposits subject to furnace heat in any boiler
may cause tubes or other heating surfaces to
overheat, bulge, or rupture.
6.3.7
6.3.9
Fusible Plugs
Some older boilers of both firetube and
watertube-type have fusible plugs. If fusible
plugs are used, determine whether they are
kept in good condition and that they are not
used for more than 1 year, as provided for in
ASME Code. When the boiler is opened,
scrape clean and brighten the exposed
surface of the fusible material as well as the
surface of the boiler near the plugs. If the
fusible metal does not appear sound, renew
the plug. Never refill a plug with anything but
new metal.
Corrosion and Grooving
Corrosion along or immediately adjacent to a
joint or seam is more serious than a similar
amount of corrosion in the solid plate.
Grooving or cracking along longitudinal seams
is especially significant as it is likely to occur
when the material is highly stressed. Severe
corrosion is likely to occur at points where the
circulation of water is poor, such places
should be inspected carefully.
Careful
should
pitting,
place in
Stays
6.3.10 Localization of Heat
inspection of the interior of the boiler
be made for cracks, broken stays,
corrosions, erosion, scale, and thin
the drums.
Localization of heat caused by an improperly
adjusted or defective burner or by poor stoker
installation or operation, creating a blowtorch
effect upon the furnace and tubes, should be
corrected and the affected area should be
inspected while the boiler is shut down.
The interior face of riveted joints should be
examined for conditions of riveting, thinness of
metal, corrosion, cracks, and other defects or
faults.
6.3.11
Freedom of Expansion
When boiler or boiler parts are suspended, the
supports and settings should be examined
carefully, especially at point when the boiler
structure comes near the setting walls or floor
to make sure that the ash and soot will not
restrict the boiler and produce excessive
strains due to thermal expansion under
operating conditions.
Particular attention should also be given to the
tube ends, tubesheets, and drums. The plant
inspector should note any corrosion or
cracking of the tubesheets, tube ends,
furnaces, or drums, signs of leaking tubes,
excessive thinning of the tubes from repeated
rolling, and the condition of any ferrules and
nipples within the drums.
6.3.12 Lap Joints
The plant inspector should note any evidence
of corrosion or cracking due to leakage at
manholes and handholes.
Boilers with riveted lap joints are apt to crack
where the plates lap in the longitudinal or
142
CHAPTER 7- BOILERS AND PRESSURE VESSELS
straight seam. If there is any sign of leakage
or other distress at this joint, it should be
investigated thoroughly to determine if cracks
exist in the seam. Any cracks noted in the
shell plate are usually dangerous.
solid particles should be inspected carefully
for erosion. The inspector should inspect
baffles and walls, particularly for holes, which
may permit short circuiting of gases. The plant
inspector should inspect soot blowers, where
used, and also the boiler tubes for cutting or
erosion due to discharge from the blower
nozzles. The plant inspector should enter the
furnace for the inspection of the exterior of
tubes, drums, brickwork, and baffles.
6.3.13 Fire Surfaces
Particular attention should be given to plate or
tube surfaces exposed to fire. The plant
inspector should observe whether any part of
the boiler has become deformed during
operation by bulging or blistering. If bulges or
blisters are large enough to seriously weaken
the plate or tube, or if water is leaking such a
defect, the boiler should remain out of service
until the defective part or parts have received
proper repairs. Careful observation should be
made to detect leakage from any part of the
boiler structure, particularly in the vicinity of
seams and tube ends.
In watertube boiler, it should be noted whether
the proper flue gas baffling is in place. The
deterioration of baffling often causes high
temperature on portions of the boiler structure,
which are not intended for such temperatures
and may result in a dangerous condition. The
location of combustion arches with respect to
tube surfaces should be noted to make sure
they do not cause the flame to impinge on a
particular part of the boiler and produce
overheating.
The plant inspector should inspect the setting
for cracks and settlement. Where brickwork is
used as insulation of steel supporting
members, it should be examined to see that it
is in good condition and that the air space, if
any, is maintained. The furnace refractory
should be examined for spalling, and
settlement.
In vertical watertube boilers, the bridgewalls
should be inspected to see that the mud drum
is properly protected. In sectional and nonsectional header-type watertube boilers, the
front and rear walls should be examined to
make sure that the bottoms of the headers are
properly protected. Tile or refractory for
protection of drums should be examined
carefully to make sure that drum plates are not
exposed directly to furnace flames or gases. A
defective condition of refractory and/or
insulation can be detected during operation by
location of hot spots on the casing or other
outer covering of the furnace and boiler.
6.3.14 Watertube Boilers
The interior of the tubes should be examined
for scale and deposits. Tube ends should be
examined for wastage of metal, brittleness,
and short tubes.
Where waterwalls are used, selected
handholes should be opened in the headers.
These headers should be thoroughly
inspected for corrosion or deposits and
cleaned out, if necessary, to prevent failures
of waterwall tubes when starting up.
6.3.15 Firetube Boilers
6.3.15.1
Tube Defects
The condition of the internal pipes in the
steam drum should be inspected to see that
their opening and perforations are free form
deposits. All interior fittings should be
inspected for loose connections and damaged
or missing gaskets.
Tubes in horizontal firetube boilers
deteriorate more rapidly at the ends toward
the fire. They should be carefully tapped
with a light hammer on their outer surface to
determine if there has been a serious
reduction in thickness. They should be
inspected as far as possible either through
the handholes, if any, or inspected at the
ends.
Furnace wall headers that are partially
exposed to radiant should be inspected
carefully for any evidence of cracking. Drums,
tubes, and headers of boilers fired by coal or
other fuels containing or producing abrasive
The surface of tubes should be carefully
inspected to detect bulges, cracks, or any
evidence or defective welds. Where there is
a high gas velocity, the tubes may become
eroded by the impingement by particles of
143
CHAPTER 7— BOILERS AND PRESSURE VESSELS
The plant inspector should inspect the boiler
for alignment, setting, loss of plumb, or
abnormal movement such as displacement of
drums or other pressure parts. He should
ensure that provisions are made for expansion
and contraction of the boiler and setting, that
external clearances for boiler expansion are
unobstructed, and that all supports are in
proper condition to carry loads imposed on
reference marks or
Permanent
them.
and headers are
drums
indicators on
rechecking their
enable
d
to
recommende
position (both hot and cold). The plant
inspector should verify that proper expansion
movement occurs as the boiler is returned to
service after an outage. Water sealed
expansion joints between the furnace and ash
pit should be examined for leaks in the baffle
and for accumulation of sludge.
fuel and ash. A leak from a tube frequently
causes serious erosion action on a number
of tubes in its immediate vicinity. The
exterior of the tubes should be inspected for
scale and deposits. The space between the
tubes should be made visible by lowering a
small light between them for the purpose of
making sure that there is no restriction of
circulation.
6.4.10.2
Ligaments Between Tube Holes
The ligaments between tube holes in the
heads of all fire tube boilers should be
inspected. If leakage is noted, broken
ligaments could be the reason.
6.4.10.3
Manholes and Other Openings
The manholes and other reinforcing plates,
as well as nozzles and other flanged or
screwed connections on the boiler, should
be inspected internally and externally to see
that they are not cracked or deformed.
Manhole ring surfaces should be examined
Particular
for erosion and corrosion.
attention should be given to areas of the
shell where feedwater piping terminates.
Whenever possible, observation should be
made from inside the boiler to check
soundness of pipe connections to the boiler.
All opening to external attachments, such as
connections to the low water cutoff and
opening to safety relief devices, should be
inspected to see that they are from
obstruction.
6.4.10.4
Inspection should be made for evidence of
corrosion of the exterior of drums or tubes and
a check made for leaks from root, stacks,
valves, or pipes. Riveted joints, butt straps,
and riveted heads should be examined for
leaks or wastage. If tell tale holes are provided
on stays, they should be kept clean. If there is
evidence of leakage, the stay should be
replaced. Where butt straps are covered by
masonry or insulation, periodic testing and
inspection for expansion is recommended.
Supporting steel, buck stays, and tie rods
should be inspected for condition and possible
shifting from place.
6.5.2
The condition of the main steam header, its
connections to the boiler, and its support units
should be inspected to determine that it is
properly supported, that allowance is made for
expansion and contraction without exerting
excessive stress or strain on the pressure
parts of the boiler, and that the non return and
stop valves in good working condition.
Fire Surfaces
Firetubes sometimes blister but rarely
collapse. The plant inspector should
examine the tubes for such defects; if any
are found to have sufficient distortion to
warrant it, they should be replaced.
Inspection of firetube boilers include a check
for any impingment of flame on dry sheets,
particularly at the back arch of return tubular
boiler. The arch should be entirely clear of
the rear tube sheets with sheet metal or
asbestos rope closing the gap.
6.5
6.5.1
Piping
All piping should be inspected for leaks; if any
are found, it should be determined whether
they are the result of excessive strains due to
expansion or contraction or other causes. The
general arrangement of the piping in regard to
the provisions for expansion and drainage, as
well as adequate support at the proper points
should be carefully noted. There should be no
pockets in the connecting piping that can hold
water unless they can be drained or equipped
with stream traps.
Inspection of External Surfaces and Part
General
144
CHAPTER 7— BOILERS AND PRESSURE VESSELS
The connections between individual boilers
and the supply and return headers should be
especially noted to see that any change of
position of the boiler due to settling or other
causes has not placed an undue strain on the
piping.
The plant inspector should also determine that
no parts, including all water pipes, are subject
to undue vibration. Special attention should be
given to blowoff pipes, connections, and
fittings because expansion and contraction
due to rapid changes in temperature and
water hammer action cause strain upon the
entire blowoff and drain connection on each
boiler should be tested by opening the valve
for a few seconds to determine whether there
is excessive vibration.
6.6.1
The plant inspector should report improper
housekeeping to his immediate supervisor.
Materials for repair or maintenance should not
be stored in a manner that will obstruct proper
access to the boiler, furnace, or firing
equipment. Any steam or water leaks should
be reported to his supervisor. If the leak is
from the shell, drum, or other than from a tube
or pipe joint, it may be cause for immediate
shutdown for investigation.
6.6.2
Safety Valves
6.6.3
Record Keeping and Logs
Boiler Appurtenances
6.6.3.1
Boiler appurtenances such as gage glasses,
gage cocks, water columns, water level
controls, high and low water alarms or cutoffs,
blowoff valves, feed valves, and non-return
valves should be inspected and tested at
regular
intervals
and
during
external
inspections or as required by the Authorized
inspector. Boiler pressure gages and master
gages should be checked with other reliable
gages in the same system or be compared
with a properly calibrated test gage.
6.6
Certificates and/or Licenses
The Philippines requires licensed and certified
personnel to operate and maintain power
boilers. All inspection certificates and licenses
or certificates of personnel shall be posted in
an appropriate place. Owner or operators of
the power boiler should ensure that all
jurisdictional requirements are met and, that
permits and certificates are posted.
As the safety valve is the most important
safety device on the power boiler, it should be
inspected with the utmost care. Safety valves
should be inspected and tested as prescribed
in ASME Code.
6.5.4
Housekeeping
Generally, a neat boiler room indicates a wellrun plant. The boiler room should be kept free
of all material and equipment not necessary to
operate the power boiler. Good housekeeping
should be encouraged, and procedures should
include routine inspection to maintain a
desired level of cleanliness.
The blowoff connections should be inspected
carefully for corrosion and weakness where
they connect with the boiler. The protective
cover of brick or tile should be intact and not
interfere in any way with the expansion of the
boiler or pipe. Blowoff lines, if embedded in
masonry, should be periodically exposed for
inspection. Blowoff piping should be supported
externally, if necessary, in such a manner that
will drain properly and will not impose
excessive stress on the drum connection while
either cold or hot and during blowdown.
6.5.3
Safety is very important and should be
foremost in the minds of those who are
assigned to inspect, operate and maintain
power boilers. Only properly trained qualified
personnel should inspect, operate and repair
power boilers.
General
All drawings, wiring diagrams, schematic
arrangements, Manufacturer’s descriptive
literature, spare parts list, written operating
instruction, Manufacturer’s suggested care
and maintenance, and other pertinent data
should be kept permanently in the boiler
room or other suitable locations so it will be
kept permanently in the boiler room or other
suitable locations so it will be readily
available to those who operate and maintain
the power boiler. When changes or
additions are made, the data and drawings
should be revised accordingly.
Care and Maintenance
145
CHAPTER 7— BOILERS AND PRESSURE VESSELS
an Authorized Inspector and should see that
all recommendations in such reports are
promptly and carefully considered.
The plant inspector should have available
for the benefit of the Inspector all pertinent
data on the boiler unit as to design,
dimensions, age, particulars about previous
defects, modifications, or repairs.
6.7
When repairs have been made, especially tube
replacement, the plant inspector should observe
whether the work has been done properly.
Excessive rolling of tubes, where they are
accessible, is a common fault of inexperienced
workmen. However, when it is difficult to reach
the tube end and observe the extent of the
rolling, they are frequently under-rolled. This
inadvertently results in separation of the parts
and leakage.
A record of each inspection should be kept
in a uniform manner so that any change of
condition can be definitely noted and
compared, especially with reference to the
thickness of scale, corrosion, erosion,
cracks, and other unusual conditions.
Between periodic inspections by the
authorized Inspector, the plant inspector
should closely observe the operation and
condition of the boiler and should report
immediately to the plant engineer or plant
management any serious defects, doubtful
conditions, or unusual occurrences.
6.6.3.2
When damage to pressure parts is encountered,
requiring repairs by processes such as welding,
the review and acceptance of an Authorized
Inspector should be obtained on the manner in
which the repair is to be made. It may also be
necessary to contract the Authorized Inspector
prior to retubing and rerolling of tubes. A
hydrostatic test may be required if repairs are
made, as required by the Authorized Inspector.
Permanent Log Book
A permanent log book should be provided
for each power boiler in the plant to record
inspections, tests,
maintenance work,
data. Brief
pertinent
other
repairs, and
details of repairs and other work performed
be recorded.
on the boiler should
Performance of tests and inspections
required by jurisdictions or insurance
companies should also be recorded.
6.6.3.3
Repairs
6.8
Hydrostatic Test.
When there is a question or doubt in the extent
of a defect found in a boiler, the Authorized
Inspector, in order to more fully decide upon its
seriousness, may request the application of a
hydrostatic test.
Daily Log
A daily log for scheduling and recording
work performed and maintenance, testing,
and inspection is recommended. The routine
work normally performed on power boilers is
As each portion of the work is
listed.
completed, the person performing the work
should enter the date and his initials in the
appropriate spaces.
Hydrostatic test pressure should not exceed 11/2 times the maximum allowable working
pressure. During the test, the safety valves
should be gagged or removed from the boiler as
should all controls and appurtenances unable to
withstand the test pressure without damage. It
is suggested that the minimum temperature of
the water be 70°Fand a maimum of 12OF.
The plant inspector should note particularly
any evidence or carelessness in the
maintenance and operation of the boiler and
related equipment.
For new generation Boilers, (Boilers used for
utility power generation) wher hydrostatic testing
at 1.5 times Maximum Allowable Pressure
requires
and
downtimes
costly
entails
modification of section, thereby causing major
disruptions in plant operations tht adversely
affect economic activities, the following testing
procedures is hereby adopted:
The plant inspector should recommend
immediate correction of any unsafe
conditions or undesirable practices that may
be discovered and should report promptly
and fully on the results of his inspection to
his immediate superiors.
a.
The plant inspector should be furnished a
copy of all reports of inspections made by
146
In new installations, before operation,
hydrostatic test at 1.5 times design
pressure.
CHAPTER 7— BOILERS AND PRESSURE VESSELS
b.
Hydrostatic testing shall be conducted at
least every 5 years thereafter at a test
pressure not exceeding 1.5 times but not
lower than 1.2 times the Maximum
Allowable Working Pressure.
6.9
6.9.1
6.9.2
I.
blow-off piping and valves;
Internal Inspection
Examine the following:
While hydrostatic test may not be conducted
in boiler used for utility power generation
during annual safety inspection, the
inspection fee as prescribed shall still be
paid to the government agency concerned
during the annual internal inspection
conducted.
d.
evidence of corrosion or erosion;
m. pressure gage, gage cocks! water glass.
Hydrostatic testing may be conducted during
shutdown for maintenance purposes at a
text pressure not greater than the set
pressure of the safety valve having the
lowest setting.
c.
k.
Boiler General
-
All Inspections
a.
internal surfaces for scale deposits, oil
deposit, other deposits, active / inactive
corrosion, erosion, grooving, bulging,
defective rivets,
warping, cracking,
bowed, loose or broken stays, water feed
line obstructed; and
b.
low water fuel supply cut-out dismantled,
condition,
float
electrical
bellows,
connections, mercury switches, and
probe-type porcelains.
6.10 Authorized Inspector
The following features of all boilers should be
checked during each inspection:
a.
safety / relief valve nameplate capacity,
set pressure, connection to boiler,
discharge line, testing;
b.
low water fuel supply cut-out, level control
or regulator, water feeder controls
combined / separate, stop valves in
connection lines, testing;
c.
controls operative, control maintenance
d.
flue and damper arrangement, combustion
safeguards;
e.
burner refractory, flame
baffles, lining, supports;
source of feedwater, condition
feedpump, feedwater treatment;
g.
condensate
returned;
system,
h.
review of boiler
operating logs;
i.
buried line, line leakage;
j.
steam pipe supports,
expand and contract;
When required by the jurisdictional authority
the Authorized Inspector should make an
internal and external inspection of all power
boilers at least once each year and any
additional inspections that the Authorized
Inspector may deem necessary. In some
jurisdictions, the annual internal inspection
may be extended, if certain conditions are
met.
impingement,
f.
return
Authorized inspector is defined in 6.1 a.
When certification and/or licensing are
required by the jurisdictional authorities, the
Authorized Inspector is normally the individual
who will make the required inspections for the
issuance of the certificate and/or license to
operate.
of
amount
maintenance
piping
When required by the jurisdictional authority,
the Authorized Inspector should make an
inspection prior to placing boilers in service for
the first time. This inspection should be as
outlined in 6.2.
free
and
The Authorized Inspector should review, for
acceptance, the manner in which repairs or
alterations are to be made to ensure that
Code integrity of the power boiler is
maintained.
to
The Authorized Inspector may require and
witness a hydrostatic test whenever repairs
have been made, or when there is a question
147
CHAPTER 7— BOILERS AND PRESSURE VESSELS
or doubt about the extent of a defect found
during inspection of a power boiler.
a.
Blow-off piping from a power boiler or
miniature shall not discharge directly into
a sewer. A blow-off tank shall be used
where conditions do not provide an
adequate and safe open discharge.
b.
Blow-off tanks hereafter installed, if made
of metal shall have a plate thickness of not
less than 8 mm diameter and shall be
designed for a minimum working pressure
of 0.345 MPa or 3.45 bars.
c.
The outlet from the blow-off tank shall be
twice the area of the inlet pipe and made
to extend internally within 203 mm from
the bottom of the tank.
d.
A vent pipe at least four (4) times the area
of the inlet pipe shall lead to the outer
atmosphere.
e.
Vents shall be as direct as possible to the
outer air and discharge at a safe location.
There shall be no valve or other possible
obstructions such as water pockets,
between the tank and the discharge end
of vent pipe.
f.
All pipe connections between the tank and
the boiler shall be as direct as possible
and shall conform to ASME Boiler
Construction Code or its equivalent.
g.
For convenience in cleaning the tank, a
manhole or an access opening shall be
provided.
h.
Where a blow-off tank is not vented as
specified above, it shall be constructed for
a pressure equal to that allowed on the
boiler to which it is attached or shall be
equipped with a safety valve or valves of
sufficient capacity to prevent the pressure
from exceeding the safe working pressure
of the tank.
The plant inspector should accompany the
Authorized Inspector during his inspection.
6.11 Low Water Fuel Cut-Offs
All automatically-fired system or vapor boilers,
excepting boilers a constant attendant who
has no other duties while the boilers is in
operation, shall be equipped with an automatic
low-water fuel cut-off and/or water feeding
device so constructed that the water inlet
valve cannot feed water into the boiler through
the float chamber, and so located as to
automatically cut off the fuel supply and/or
supply requisite feedwater when the surface of
the wall falls to the lowest safe water line.
This point should be not lower than the bottom
of the water glass.
Such a fuel of feedwater control device may
be attached direct to a boiler or to the tapped
openings provided for attaching a water glass
direct to the boiler, provided that such
connections from the boiler are non-ferrous
tees or Y’s not less than 12.7 mm diameter
pipe size between the boiler and the water
glass so that the water glass is attached direct
and as close as possible to the boiler; the
straightway tapping of the Y or tee to take the
water glass fittings, the side outlet of the Y or
the tee to take the fuel cut-off or water feeding
The ends of all nipples shall be
device.
Designs
reamed to full size diameter.
embodying a float bowl shall have a vertical
straight-a-way valve drain pipe at the lowest
point in the water equalizing pipe connections
by which the bowl and equalizing pipe can be
flushed and device tested.
6.12 Safety Gadgets I Cut-Outs
No person shall remove or tamper with any
safety gadgets or components prescribed by
these rules except for the purpose of making
repairs. The resetting of safety gadgets or
components shall be done in the presence of
the
of
representative
authorized
an
government agency concerned.
7.2
a.
Section 7.0 BIow-Offs, Pressure
Reduction, Fire Explosion Devices
7.1
The discharge of
Location of Blow-Offs.
safety valves, blow-off pipes and other outlets
shall be located so as to prevent injury to
personnel or avoid making a nuisance to the
surrounding vicinity.
Blow-Off Tanks
148
Where
Underground Installations.
,
underground
install
a
vessel
necessary to
it shall be enclosed in a concrete or brick
pit with a removable cover so that
CHAPTER 7— BOILERS AND PRESSURE VESSELS
inspeclion of the entire shell and heads of
the vessel can be made.
b.
7.3
A suitable screen or guard shall be
provided around high-tension bushing and
a sign posted warning of high voltage.
This screen or guard shall be located that
it will be impossible for anyone working
around the generator to accidentally come
in contact with the tension circuits. When
adjusting safety valves, the power circuit
to the generator shall be open.
The
generator may be under steam pressure
but the power line shall be open while the
operator is making the necessary
adjustments.
c.
Each kW electrical energy consumed by
an electric steam generator operating at
maximum rating shall be considered the
equivalent of 0.093 m
2 of heating surface
of a fire tube boiler when determining the
required amount of safety valve capacity.
Supports. Each unfired pressure vessel
shall be supported by masonry or
structural supports of sufficient strength
and rigidity to safely support the vessel
and its contents.
There shall be no
vibration in either the vessel or its
connecting piping.
Pressure Reducing Valves.
a.
b.
c.
d.
7.4
b.
Where pressure reducing valves are used,
one or more relief safety valves shall be
provided on the low pressure side of the
reducing valve in case the piping or
equipment on the low pressure side does
not meet the requirements for the full
initial pressure. The relief or safety valves
shall be located adjoining to or as close as
possible to the reducing valve. Proper
protection shall be provided to prevent
injury or damage caused by the escaping
steam form the discharge of relief or
safety valves if vented to the atmosphere.
Section 8.0 Other Testing Methods
For existing boilers within the five (5) year interval of
hydrostatic testing, any one of the following methods
may be undertaken. This, however, is not mandatory.
The combined discharge capacity of the
relief valves shall be such that the
pressure rating of the lower pressure
piping or equipment shall not exceed in
case the reducing valve sticks open.
8.1
The test is carried out by drawing vacuum of
approximately 60 mbar-abs, through the system
using vacuum pumps at the condenser side or
at any other convenient location to the boiler.
Using an ultrasonic monitor for noise detection,
reading of more than 30 dB emanating from
each different location within the boiler will give
an indication of possible leaks or abnormal
conditions that must be thoroughly investigated
and corrected.
The use of hand-controlled bypasses
around reducing valves is permissible.
The by-pass if used around a reducing
valve shall not be greater in capacity than
the reducing valve unless the piping or
equipment is adequately protected by
relief valves or meets the requirements of
the high pressure system.
8.2
It is mandatory that a pressure gage be
installed on the low-pressure side of a
reducing valve.
Ultrasonic Thickness Gauging
The test is based on the amount of time it takes
generated sound waves to pass through a
material and back to the source after being
reflected.
The difference in time is translated
into thickness measurement of the material
being tested. The test shall be performed on all
tubes with any indication of erosion.
Tube
below recommended nominal wall thickness
shall be repaired using weld overlaid or replaced
as per currently practiced repair procedures.
Electric Steam Generators.
All appliances
required for electric steam generators shall be
attached in accordance with the following:
a.
Vacuum Testing
A cable at least as large as one of the
incoming power lines to the generators
shall be provided for grounding the
generator shell.
This cable shall be
permanently fastened on some part of the
generator and shall be grounded in an
improved manner.
8.3
Radiographic Testing
X-rays shall be used to penetrate and record on
film the imperfection or defects in the boiler tube
149
CHAPTER 7— BOILERS AND PRESSURE VESSELS
materials and to determine integrity of welds.
All welds performed on pressure parts during
outages shall be evaluated using this method.
8.4
8.5
Tube Sampling
Periodically, samples of boiler tubing shall be
removed from each water wall above the burner
superheater,
pendant
elevations,
platen
reheater, and economizer sections and
examined in a metallurgical laboratory. Tube
microstructure analysis, tube hardness and
thickness tests shall be performed, the results of
which are to be used in predicting the remaining
life of the boiler.
Metallurgical Replication
This method shall be used to verify the
microstructure of the boiler tubes. The metal
surfaces to be examined shall be polished using
fine abrasives until a mirror-like surface is
obtained. The resulting surface shall be etched
using an appropriate acid and applying softened
acetate film to obtain a reproducible image of
The
the microstructure of the material.
replicated images of the sample or component
shall be examined in a metallurgical laboratory
using optical microscopes.
150
CHAPTER 8— HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
Chapter 8
HEATING, VENTILATING, REFRIGERATION
AND AIRCONDITIOMNG
Section 1.0 Definitions
Approved
jurisdiction.
Refrigeration the process of absorbing heat from a
place where is not needed and transferring it to a
place where it is unobjectionable.
-
-
acceptable to the authorities having
Brazed Joint for the purpose of this Code, a brazed
joint is a gas joint, obtained by the joining of metal
parts with alloys which melt at temperature higher than
538°C, but less than the melting temperature of the
joined parts.
-
Refrigeration System an assembly of our (4) major
components, namely the Compressor, Condenser,
Expansion Valve, the Evaporator, through which a
very low boiling point substance (Refrigerant) flow in
cycle, and absorbs heat from the immediate
surroundings, thereby producing the cooling effect
(also known as the Refrigerating effect).
-
Brine any liquid cooled by the refrigerant and used
for the transmission of heat without a change in its
state, having no flash point or a flash point above
65.6°C as determined by the American Society of
-
Air Conditioning the process of treating air so as to
control simultaneously its temperature, humidity,
cleanliness and distribution to meet the requirements
of the conditioned space.
Testing Materials method D93.
—
Compressor
a mechanical device used in
refrigeration system for the purpose of increasing the
pressure upon the refrigerant.
-
Ventilation the process of supplying or removing air
by natural or mechanical means to or from any space.
Such air may or may not have been conditioned.
Condenser
a vessel or arrangement of pipe or
tubing in which vaporized refrigerant is liquefied by the
removal of heat.
-
Humidity
unless otherwise stated will mean the
relative humidity in per cent. This is the ratio of the
actual (measured) partial pressure of the water vapor
in the air mixture to its saturation pressure at the same
dry bulb temperature. This is also the ratio of the
actual weight of moisture per cubic meter of mixture to
the saturated water vapor per cubic meter of mixture
at the same dry bulb temperature.
—
Condensing Unit a specific refrigeration machine
combination for a given refrigerant, consisting of one
or more power-driven compressors, condensers, liquid
receivers (when required) and the regularly-furnished
accessories.
-
Design Working Pressure the maximum allowable
working pressure for which a vessel is designed.
-
Effective Temperature
an empirically determined
index, which combines into a single value the effect of
temperature, humidity and air movement on the
sensation of warmth or cold felt by the human body.
The numerical value is that of the temperature of still
saturated air which could induce an identical
sensation. The wide range of effective temperature is
indicated on graphical representation of comfort zone.
-
Ton of Refrigeration
equal to (211 KJ/min.)
Note:
=
=
-
Evaporator that part of the system in which liquid
refrigerant is vaporized to produce refrigeration.
-
Expansion Coil
tubing.
-
an evaporator constructed of pipe or
Fusible Plug
a device having a predetermined
temperature fusible member for the relief of pressure.
-
the useful refrigerating effect
Generator
any device equipped with heating
element used in the Refrigerating System to increase
the pressure of the refrigerant, in its gas or vapor state
for the purpose of liquefying the refrigerant.
-
288000 Btu/24 hrs
12000 Btu/hr
12000x 1.55 = 12660 kJ/hr
151
CHAPTER 8— HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
Liquid Receiver a vessel permanently connected to
a system by inlet and outlet pipes for storage of a
liquid refrigerant.
evaporators (each separate section of which does not
exceed 340 liters of refrigerant containing volume),
expansion coils, compressors, controls headers, pipes
and pipe fittings.
equipment including ay or all of the
Machinery
following compressor, condenser, generator, absorber,
receiver, connecting pipe, evaporator, air handling
units, dehumidifier, humidifier, heat exchanger,
complete unit system.
a substance which absorbs heat at a
Refrigerant
low pressure and temperature and rejects heat at a
high pressure and temperature.
-
-
—
a.
a
Refrigerating System, Absorption
refrigerating system in which the refrigerant
gas evolved in the evaporator is taken up in
an absorber and released in a generator upon
the application of heat.
b.
an indirect
Refrigerating System, Brine
refrigerating system employing brine as the
circulating liquid.
c.
a
Refrigerating System, Brine Spray
refrigerating scheme for cooling by a mist or
spray of brine.
d.
one
Refrigeration System, Cascade
having two or more refrigerant circuits, each
with a pressure-imposing element, condenser
and evaporator, where the evaporator of one
circuit cools the condenser of another (lower
temperature).
e.
a
Refrigerating System, Central Point
connected
sides
low
more
or
with
two
system
to a single, central high side; multiple system.
a specific room in which is
Machinery Room
operated Refrigerating and
and
instalied
permanently
Air Conditioning machinery. Closets solely contained
within and opening only into a room shall be
considered a part of such room.
-
Machine Room, Class I a room having machinery
other than flame producing apparatus permanently
installed and operated and also having:
—
—
—
—
a.
Doors which are tight-fitting, fire-resisting, and
self-closing.
b.
Walls which are vapor-tight and of approved fire
resistive construction.
c.
An exit door which opens directly to the outer air
or through a vestibule-type exit equipped with
self-closing, tight-fitting doors.
d.
Exterior openings which, if present, are not
under any fire escape or any open stairway.
e.
All pipes piercing the interior walls or floor of
such room, tightly sealed to the walls or floor
through which they pass.
f.
an
Refrigerating System, Chilled Water
indirect refrigerating system employing water
as the circulating liquid.
Emergency remote controls located immediately
outside to stop the action of the refrigerator
compressor.
g.
a
Refrigerating System, Compression
refrigerating system in which the pressureimposing element is mechanically operated.
Emergency remote controls for the mechanical
means of ventilation located outside.
h.
Refrigerating System, Direct Expansion a
refrigerating system in which the evaporator is
in direct contact with the refrigerated material
or space or is located in air circulating
passages communicating with such spaces.
i.
a
Flooded
System,
Refrigeration
refrigerating system in which only part of the
refrigerant passing over the heat transfer
separated from the vapor and recirculated.
j.
a
Indirect
System,
Refrigerating
as
such
liquid,
which
a
in
system
refrigerating
brine or water cooled by the refrigerant, is
f.
g.
Mechanical Joint for the purpose of this Code, a
mechanical joint, obtained by the joining of metal parts
through a positive holding mechanical construction.
—
pipe or tube mains for interconnecting the
Piping
various parts of a Refrigerating System.
—
Pressure Limiting Device a valve held closed by a
spring of other means and designed to automatically
relieve pressure in excess of its setting.
—
any refrigerant containing
Pressure Vessel
receptacle of a refrigerating system, other than the
—
152
—
—
-
-
-
-
-
I
CHAPTER 8— HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
circulated to the material or space refrigerated
or is used to cool air so circulated.
k.
I.
Tenant as herein used a tenant shall be construed
as a person, firm, or corporation possessed with the
legal right to occupy premises.
-
Refrigerating System, Mechanical
a
refrigerating system employing a mechanical
compression device to remove the low
pressure refrigerant enclosed in the low
pressure side and delivers it to the high
pressure side of the system.
-
Welded Joint for the purpose of this Code, a welded
joint is a gas-tight, obtained by the joining of metal
parts in the plastic or molten state.
-
Section 2.0 Air Conditioning and
Ventilation Standards
Refrigerating
System,
Multiple
a
refrigerating system using the direct method in
which refrigerant is delivered to two or more
evaporators
in
separate
rooms
or
refrigerators.
-
2.1
m. Refrigerating System, Single-Package
a
complete factory made and factory-tested
refrigerating system in a suitable frame or
enclosure which is fabricated and shipped in
one or more sections and in which no
refrigerant-containing parts are connected in
the field.
The temperature and humidity of the air to be
used for comfort cooling shall be maintained at
20°-23.3°C effective temperature at an air
movement of from 4,570 to 7,620 mm/mm within
the living zone and 55 to 60% relative humidity.
-
n.
o.
Table 8.2
Desirable Indoor Conditions for
Different Outdoor Temperature
Outdoor Temperature
Indoor Temperature °C
Dry Bulb °C
Dry Bulb
Effective
39
24
28
35
23
27
32
23
27
29
22
26
27
22
25
Refrigerating System, Steam-Jet Vacuum a
water vapor refrigerating system in which high
pressure steam, supplied through a nozzle
and acting to eject water vapor from the
evaporator, and produces the requisite
pressure on the high side by virtue of
compression in a following diffusion passage.
2.2
The indoor air quality in such occupy shall all
times be free from toxic, unhealthful, of
disagreeable gases and fumes and shall be
relatively free from odors and dust; and shall
conform
with
internationally
accepted
standards, e.g., American Society of Heating
Refrigerating
Conditioning
and
Air
Engmneers(ASHRAE)
2.3
The air in such occupied spaces shall at all
times be in constant motion sufficient to
maintain a reasonable uniformity of temperature
and humidity but shall not cause objectionable
drafts in any occupied portion. The air motion in
such occupied spaces, and in which the only
source of contamination is the occupant, shall
have a velocity of not more than 0.254 meter per
minute as the air enters the living zone or 1,830
mm above the floor.
2.4
Air in all rooms and enclosed spaces shall be
distributed with reasonable uniformity, and the
variation in carbon dioxide content of the air
shall be taken as a measure of such distribution.
The carbon dioxide concentration when
measured 910 mm above the floor shall not
exceed 100 ppm (parts per million).
Refrigerating System, Vapor a refrigerating
system employing a condensable vapor as the
refrigerant.
Heat Pump
uses the same equipment as a
refrigeration system but it operates for the purpose of
delivery heat at a high level of temperature. Even
though the equipment used in a refrigeration cycle and
in a heat pump maybe identical, the objectives are
different. The purpose of a refrigeration cycle is to
absorb heat at a low temperature; that of a heat pump
is to reject heat a t a high temperature.
-
Rupture Member
a device that will automatically
rupture at a predetermined pressure.
-
Soldered Joint
for the purpose of this Code, a
soldered joint is a gas-tight joint, obtained by the
joining of metal parts with the metallic mixtures or
alloys, which melt at temperatures below 538°C and
above 177°C.
-
Stop Valve a shut-off valve other than a valve for
controlling the flow of refrigerant.
-
153
_____________________
CHAPTER 8- HEATING, VENTILATING, REFRIGERATION AND AIRCOND1TIONING
2.5
2.8
The quality of air used to ventilate the space
during the occupancy shall always be sufficient
to maintain the standards of air temperature, air
quality, air motion and air distribution.
Ventilation requirements shall conform to the
following Table 8.2.
Refrigerant Classifications:
Group 1:
Carbon Dioxide
Dichlorodifluoromethane
Dichloromonofluoromethane
Dichlorotetra fluoroethane
Dichloromethane
2
CO
F
2
CCI
R-12
R-22 CHCL
F
2
CL
C
4
F
R114 2
CL
Ch
Carrene 2
No. I
F
3
CCL
Trichloromonofluoromethane R-1 I
Table 82
Outdoor Air Reauirement
Application
Apartment, average
Banking Space
Barber Shop
Beauty Parlor
Board Room
Cocktail Bar
Department Store
Director’s Room
Drug Store
Factory
5 & 10 Stores
Funeral Parlor
Hospital, Private Room
Hospital, Ward
Hotel Room
Laboratories
Meeting Room
Offices, General
Restaurant, Cafeteria
Dining Room
Shop, Retain
Theater
Liters per
second/person
Recommended
12
9.5
11.8
12
11.8
14
7.5
11.8
7.5
7.5
7.5
11.8
11.8
9.5
17
9.5
11.8
9.5
9.5
9.5
7.5
7.5
2.6
The desirable temperature in air conditioned
spaces increases as the outdoor temperature
increases as shown in Table 8.1.
2.7
The quantity of outdoor air required to control
body odors satisfactorily decreases as the
volume space per occupant increases.
Recommended rates of outdoor air supply for
different volumes of spaces per occupants are
as follows:
Group 2:
Ammonia
Dicholoroethylene
Ethyl chloride
Methyl Formate
Sulfur dioxide
Group 3:
Butane
Ethane
lsobutane
Propane
2.9
Outdoor Air Supply per
Occupant Ips
14
10
8
4
154
0
C
1
H
4
68
H
2
C
)
3
(CH
CH
8
H
3
C
Locations in which Refrigeration Systems may
be placed are grouped by occupancy as follows:
a.
Institutional occupancy like hospitals,
asylums, sanitariums, police stations, jails,
court houses with cells, etc.
b.
Public assembly like auditorium, assembly
rooms, ball rooms, broadcasting studios,
churches, department stores, fraternity,
halls, libraries, theaters, etc.
c.
Residential occupancy apply to portions of
buildings in which sleeping accommodations
are provided.
d.
Commercial occupancy applies to portions
of buildings used for transactions of
professional
rendering
for
business,
services or for supply of food and drinks.
e.
Industrial occupancy applies to entire
building occupied by single tenant, for
manufacturing, processing or storage of
materials or products including chemical,
food, candy, ice cream factories, ice-making
plants, meat packing plants, refineries,
perishable food warehouses and similar
occupancies.
f.
Mixed occupancies applying to a building
occupied or used for different purposes in
different parts.
Table 8.3
Minimum Outdoor Requirements to Remove
Objectionable Body Odors for Sedentary Adult Workers
Air Space per Person
3
M
3
6
9
14
3
NH
CI
H
2
C
CI
3
CH
3
HCOOCH
2
SO
CHAPTER 8
HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
2.10 Institutional Occupancies:
a.
Group I Refrigerants:
1.
No refrigerating system shall be
installed in any room except Unit
Systems each containing not more
than 4.55 kg of Group I refrigerant,
and then only when a window or
other ventilation is provided.
2.
Systems each containing not more
than 9 kg of a Group 1 refrigerant
may be installed in kitchens,
laboratories and mortuaries.
3.
Systems each containing more than
9.10 kg of Group 1 refrigerant shall
be of the indirect type with all
refrigerant
containing
parts
excepting parts installed outside the
building, installed in a machinery
room used for no other purpose and
in which Group I refrigerants
excepting carbon dioxide, no flame
is present or apparatus to produce a
flame is installed.
4.
b.
for human comfort, except in an
indirect ventured closed surface
system or in a Double Indirect
Vented Open Spray system or in an
indirect Absorptive Brine System.
2.11
Public Assembly Occupancies:
a. Group I Refrigerants:
1. The maximum quantity of a Group 1
refrigerant in a Direct system used
for air conditioning for human
comfort shall be limited by the
volume of space to air conditioned
as follows:
Carbon Dioxide
2
CO
Dichlorodifluoromethane
R-12
Dichloromethane
Carrene I
Dichioromonofluoromethane R-21
Dichlorotetrafluoromethane R-1 14
Trichloromonofluoromethane R-1 1
2.
When a Group 1 refrigerant, other
than carbon dioxide, is used in a
system, any portion of which is in a
room where there is an open flame,
then such refrigerant shall be
classed in Group 2 unless the flame
producing apparatus is provided
with a hood and flue capable of
removing
products
the
of
combustion to the open air. Flames
by matches, cigarette lighters, small
alcohol lamps and similar devices
shall not be considered as open
flames.
Group 2 refrigerants shall not be
used except in Unit Systems
containing not more than 2.72 kg of
refrigerant
installed
when
in
kitchens, laboratories or mortuaries,
or except in systems containing not
more than 227.30 kg or refrigerant
containing parts installed in a “Class
1” machinery room.
2.
Group 2 refrigerants shall not be
used in a system for air conditioning
A system containing more than
22.73 kg of Group I Refrigerant
other than carbon dioxide and which
includes air ducts shall be of the
Indirect Type unless it conforms to
the requirements as follows:
(a) Positive automatic fire damper
or dampers shall be provided to
cut off the refrigerant containing
apparatus from the duct system.
(b) Automatic means shall be
provided to close the dampers
and to stop the fan when the
temperature of the air in the
duct at the damper location
reaches 51.70°C.
Group 2 Refrigerants:
1.
.19 kg/m
3
.48 kg/rn
3
.10 kg/rn
3
2.10 kg/rn
3
6.43 kg/rn
3
5.64 kg/rn
3
3. A system containing more than
454.60 kg of a Group 1 refrigerant
shall be of the Indirect Type with all
the refrigerant
containing parts
mounted outside the building,
installed in a machinery room used
for no other purpose and in which
for Group I refrigerants, excepting
carbon dioxide, no flame is present
or apparatus to produce a flame is
installed.
4.
155
When a Group 1 refrigerant, other
than carbon dioxide is used in a
CHAPTER 8- HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
Closed Surface, Double Indirect
Indirect
Spray,
Vented
Open
Absorption Brine or in primary circuit
of a double Refrigerant containing
parts, excepting parts mounted
outside the building installed in a
machinery room used for no other
purpose.
system, many portions of which is in
a room where there is an apparatus
for producing an open flame, then
such refrigerant shall be classed in
Group 2 unless the flame producing
apparatus is provided with a hood
and flue pipe capable of removing
the products of combustion to the
open air, flames by matches,
cigarette lighters, small alcohol
lamps and similar devices shall not
be considered as open flames.
b.
3.
Group 2 Refrigerants:
1.
c.
Group 2 refrigerants shall not be
used except in Unit Systems
containing not more than 5.45 kg of
refrigerant or except in systems
containing not more than 454.80 kg
of refrigerant and having all
refrigerant containing parts installed
in a Class I machinery room.
c.
Group 3 Refrigerants:
Group 3 refrigerants shall not be used
except in a Unit System containing not more
than 2.73 kg of Refrigerant.
213 Commercial Occupancies:
a.
2.
Group 2 refrigerants shall not be
used in a system for air conditioning
for human comfort, except in an
indirect, Vented Surface Systems,
or in a Double Indirect Vented Open
Spray System or in an indirect
Absorptive Brine System.
Group I Refrigerants:
1.
b.
1.
A system containing more than 9.10
kgs of a Group 2 Refrigerant shall
not be used for air conditioning for
human comfort unless it is of the
Indirect Vented Closed Surface,
Open
Indirect Vented
Double
Surface, Indirect Absorptive Brine,
or primary circuit of a double
the
all
refrigerant type with
parts,
containing
refrigerant
excepting parts, mounted outside
the building, installed machinery
room used for no other purposes.
2.
Any system containing more than
272.73 kg of a Group 2 Refrigerant
shall have all refrigerant containing
parts installed in a Class 1
Machinery Room.
Group 3 Refrigerants:
2.12 Residential Occupancies
Group I Refrigerants:
1.
b.
Same rules as those for Public
Assembly Occupancies apply.
Group 2 Refrigerants:
1.
2.
No system containing more than
2.73 kg of a Group 2 Refrigerant
shall be located in sleeping rooms
for spaces directly connected to
sleeping room.
c.
No system containing a Group 2
Refrigerant shall be used for air
conditioning for human comfort
unless it is of the Indirect Vented
156
Same rules as those for Public
Assembly Occupancies apply.
Group 2 Refrigerants:
Group 3 refrigerants shall not be
assembly
public
in
used
occupancies.
a.
Any system containing more than
136.36 kg of Group 2 Refrigerant
shall have all refrigerant containing
parts installed in Class 1 Machinery
Room.
3
Group
Refrigerants.
3
Group
Refrigerants shall not be used except in a
unit system containing not more than 2.73
kg of refrigerant.
CHAPTER 8— HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
2.14 Industrial Occupancies. There shall be no
restriction on the quantity or kind of refrigerant
used in an Industrial Occupancy.
Table 8.4
Weight of
refrigerant
in system,
Kgpto
2.15 Water discharged from evaporators, condensers
and other machinery shall not be directly
connected to the waste or sewer system in such
a manner as to permit siphoning of the waste
water into the water supply lines. The waste
discharge from such equipment shall be over
and above the rim of a properly trapped and
vented plumbing fixture or suitable storm drain.
22.73
45.45
68.18
90.90
113.64
136.36
181.82
227.27
272.73
318.18
363.64
409.09
454.55
568.18
681.82
759.45
909.09
1136.36
1363.64
1818.18
2272.73
2727.27
3181.82
3630.36
4090.91
2.16 Machinery Rooms:
a.
Each refrigerating machinery room shall be
provided with adequate door or openings
that will permit the passage of the
machinery into the machinery room.
b.
Each refrigerating machinery room shall be
provided with means for ventilation to the
outside.
The ventilation shall consist of
windows or door opening to the outside of
the size given below or where power driven
exhaust fans are used continuously they
shall have sufficient capacity as shown in
Table 8.4
2.17 Field erected air conditioning systems shall have
the following minimum control instruments:
a.
Direct Expansions
1.
2.
3.
4.
b.
Room Thermostat;
Solenoid Valve (Liquid Line);
Compressor High & Low Pressure
Cut Off;
Compressor Low Oil Pressure Cut
Off (for compressors with positive
lubrication).
Liters
perlsecond
exhaust
fan
4.25
7.08
11.34
15.59
19.27
22.67
25.50
31.17
36.13
41.09
46.19
51.01
55.26
58.09
63.76
70.85
76.51
82.18
93.52
104.85
130.35
155.86
178.53
204.04
266.71
246.55
Duct Area
(m2)
0.023
0.31
0.046
0.062
0.062
0.093
0.093
0.116
0.116
0.139
0.139
0.186
0.186
0.186
0.209
0.209
0.209
0.209
0.232
0.279
0.349
0.418
0.465
0.511
0.534
0.581
Area of
open
Window
)
2
(m
0.372
0.558
0.929
1.162
1.301
1.394
1.580
1.859
2.045
2.231
2.417
2.603
2.788
2.881
3.067
3.439
3.532
3.718
3.997
4.462
5.112
5.763
6.321
6.878
7.436
7.901
Section 3.0 Duct System and Accessories
3.1
Design
a.
Chilled Water
1. Room Thermostats;
2. Face & Bypass Damper with
modular motor or motorized chilled
water mixing valve;
3. Chiller Flow Switch;
4. Chiller Low Water Temperature Cut
Off;
5. Compressor Low Oil Pressure Cut
Off (for compressors with positive
lubrication).
6. Compressor high and low pressure
cut-off
3.2
Fabrication I Construction
a.
157
Ducts system shall be
designed and
installed in accordance with a recognized
and acceptable method such as contained
in ASHRAE guide or applicable manuals of
the SMACNA and shall comply with National
Fire Protection Pamphlet No. 90-B, except
as other wise provided herein.
Ducts shall be constructed entirely of noncombustible materials such as steel, iron,
aluminum or other approved materials.
CHAPTER 8- HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
Tab’e 8.5
Schedule of Duct Gage and Hangers
DUCT JOINTS DETAIL
=
DRIVE SLIP
Dimension
Longest
Side
G.l.
Sheet
Size of
Angle
Support
Distance
Between
Hangers
(MM)
GA No.
26
24
22
20
18
(MM)
(MM)
Mm.
Size of
Steel
Rod
Hanger
(MM 0)
25x25x3
38x38x5
38x38x5
38x38x5
38x38x5
1200
1200
2000
2000
2000
10
12
12
12
12
Up to 300
325 to 750
785 to 750
• 1550 to 2285
2310 Up
b.
c.
d.
INSIDE GROOVE SEAN
—
Duct work shall be fabricated and erected in
a workmanlike manner so that it shall be
straight, true to dimensions, and smooth on
the inside with neatly finished and air-tight
joints. Ducts shall be cross-broken and
installed completely free from vibration
under all conditions of operation. They shall
be properly supported by hangers and
brackets and by other approved means at
intervals not more than 2,130 stiffners shall
be provided as specified, secured rigidly
with rivets or other approved fasteners.
Wall openings through which ducts pass
shall be air-tight sealed with plastic cement.
SLIDING SEAN
FIG. 8.3.1
Where sheet-metal connections are made of
felts, air handling unit of where ducts or
dissimilar metal are connected, a noncombustible flexible connection of 425
grams woven asbestos or other approved
non-combustible material approximately 152
Flexible
mm in width be installed.
fastened
by
securely
shall
be
connections
zinc-coated iron clinch-type draw bands.
f.
BRANCH TAKE-OFF DETAIL
Exposed duct sleeves and flanges shall be
fabricated from .8 mm thick galvanized
sheet steel. Flanges not less than 102 mm
wide shall be installed tight against the wall
on each side and fastened to the sleeve.
Duct insulation and vapor barrier shall
extend through the duct sleeve. Sleeve
shall be 51 mm larger than the duct unless
otherwise required by the thickness of
insulation.
FIG. 8.3.2
Access doors shall be provided at all
dampers,
fire
dampers,
automatic
thermostats, and other apparatus requiring
service and inspection in the duct system.
Doors shall be 305 mm x 457 mm unless
indicated otherwise. Where size of duct will
not accommodate this size, the door shall
be made as large as practicable.
BRANCH TAKE OFF DETAIL
BRANCH TAKE-OFF DETAIL
LUBRICATED BEARINGS
SPLIT DAMPER
AIRFLOW
FLOW?
SPLITTER
ROD
e.
Ducts may be of independent construction
or a part of the building structure provided
they are constructed in accordance with the
standards.
of
these
requirements
Constructions consisting of not less than 19
mm cement or gypsum plaster or metal lath
applied either to combustible or noncombustible supports may be used as duct
wall.
THROAT RADIUS
MEEt RADIUS
AIRFLOW
0’
HUT
Fig.8.3.3
158
_________
CHAPTER 8— HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
g.
Only fire retarding materials conforming to
the standards set by the Underwriters’
Laboratories (UL), National Fire Protection
Association and the Fire Code of the
Philippines, shall be used for duct insulation
and duct liners.
h.
Insulation materials for air ducts, pipes,
conduits, etc., shall be of sufficient thickness
so that the surface temperature of the duct,
pipe, etc., shall not be lower than the dew
point of the surrounding air.
Plenum chamber which conform to all the
requirements for ducts may be located in
any such portion of the building.
Such
chambers shall not be used for storage or
occupational purposes. Public exit halls and
corridors in hotels, hospitals, institutions,
office building and similar occupancies and
in multi-family houses used for passage of
return air shall provide an air velocity not to
exceed 0.5 meter per second within the
living zone.
Ducts shall be made reasonably tight
throughout and shall have no openings
other than those required for the proper
operation and maintenance of the system.
j.
3. 3
e.
Only fire retardant materials shall be used
inside of ducts.
f.
Insulation materials for air ducts, pipes,
conduits, etc. shall be with sufficient
thickness so that the surface temperature of
the duct, pipe, etc. shall not be lower than
the dew point of the surrounding air.
Return ducts, other than vertical, shall be
provided with access doors or openings to
facilitate
the
cleaning
of
possible
accumulation of dust and combustible
materials in them when occupancy is not
productive of combustible material.
25mm STRAPPING BAND
CONTINUOUS_ CORNER
BEADS Gj GA. 2E
Installation and Insulation of Ducts
a.
b.
c.
d.
—
26MM THIK FIBER
GLASS INSULATION
In no case shall clearance from metal ducts
to adjacent combustible materials be less
than
150 mm and to combustible
construction, including plaster of wood lath,
it shall not be less than 13 mm.
NON. FLAMMABLE
ADHESIVE MASTIC
FIG. 8.3.4
Where ducts pass thru walls, floors or
partitions, the space around the duct shall
be sealed with a material fire resistant
property equivalent to that of the wall, floor
or partition, to prevent the passage of flame
or smoke.
DUCT
Ducts which pass thru floors or fire proof
constructions, semi-fire proof construction,
or heavy timber construction, in which
vertical openings are generally protected,
shall be encased in 100 mm hollow clay tile,
gypsum block or their equivalent.
Such
construction, however, shall not be required
for branches, which are cut off from the
main portion of the duct by approved fire
dampers.
INSULATION
DETAILS
g.
Ducts shall not be built into a building in
such a way as to impair the effectiveness of
the fire proofing around steel or iron
structural members, such as placing the
ducts between the fire proofing and the
members protected.
h.
Ducts shall not be located where they will be
subject to damage rupture.
Where so
located, they shall be suitably protected.
Ducts shall be substantially supported.
Hangers and brackets for supporting ducts
shall be metal.
Ducts exposed to the
weather shall be wrapped with weather
proofing materials.
No attic, basement or concealed space in a
building shall be used as an integral part of
a duct system unless it conforms to all the
requirements for ducts.
j.
159
Approved fire dampers shall be provided
where the air ducts penetrate or terminate at
the openings in the walls or partitions these
CHAPTER 8— HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
(10°C) above the maximum temperature that
would normally be encountered with the
system in operation or shut down. Hinged
dampers shall be equipped with spring
catches and pins of hinges shall be of
corrosion resistant materials.
to have a fire resistance rating of 2 hours or
more. Approved fire dampers shall be
provided in all air transfer openings in
partitions that are required to have fire
resistance rating in which other openings
are required to be protected.
k.
The passing of supply and return ducts thru
fire walls should be avoided wherever
possible. When ducts or the outlets or inlets
to them pass through fire walls, they shall be
provided with automatic fire dampers on
both sides of the fire wall through which they
pass. On small openings not exceeding 457
mm in diameter, 9.5 mm steel plates may be
used instead of fire dampers.
n.
An approved fire damper shall be provided
an opening through a required fire partition.
o.
Where duct system serve two or more
floors, approved fire dampers shall be
required at each direct outlet and in each
branch duct at its junction with the main
vertical duct. Dampers are not required in
branch duct having a cross sectional area of
less than 129 cm
2 which supply only air
conditioning units discharging air or not over
1,220 mm above the floor.
p.
3 per minute
In systems of over 425 m
capacity serving areas where large numbers
of people congregate or areas having
valuable contents particularly subject to
smoke damage, except when system is
located on the same floor that it serves, it is
smoke
recommended
that
approved
dampers be installed in the main supply duct
and main return duct. Such dampers should
be arranged to close automatically when the
system is not in operation and also by
manual emergency motor stop or by
application of a smoke detecting apparatus.
q.
Dampers provided in ducts used solely for
exhaust of air to the outside shall be
installed in such a way that they will interfere
with the flow of air in the main duct. No
dampers are required in a system serving
only one floor and used only for exhaust of
air outside. Dampers should be designed to
close in the direction of air flow. Where
direction of exhaust air flow is upward, subducts at least 560 mm in length may be
carried up inside the main duct from each
inlet of dampers.
r.
Fresh air intakes shall be protected with
approved automatic fire doors or dampers
except where permission to omit them,
because of light exposure is granted by the
inspection department having jurisdiction.
When deemed necessary by inspection
department approved heat actuated devices
shall be installed at intake opening to shut
fans down in case of exposure fires.
See page 170 of 2003
Fig. 8.3.5
Duct Hangar Detail
-
INSULATION
ANGLE BAR
32
F,IB,3.7
—
DUCT HANGER DETAILS
Fire dampers, installed in the system as
required at other than fire wall openings
shall be 1.6 mm thick on diameter up to 914
mm or greater width and 4.55 mm on ducts
above 914 mm in diameter or greater width.
Louvered type automatic dampers may be
constructed of 1.25 mm thick steel, provided
the individual louvers are not over 152 mm
in width and are stiffened by formed edges.
m. Fire doors and fire dampers shall be
arranged to close automatically and remain
tightly closed, upon the operation of a
fusible link or other approved heat actuated
device located where readily affected by an
abnormal rise of temperature in the duct.
Fusible link should have a temperature
rating approximately 10 degrees centigrade
160
CHAPTER 8— HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
Section 4.0 Heat Gain Calculations
Section 6.0 Air Intake and Outlets
4.1
6.1
Calculations shall be made in accordance with
the American Society of Heating Refrigerating
Air Conditioning Engineering (ASHRAE) Guide,
Air Conditioning and Refrigerating Institute
Standards, the applicable manuals of the
National Warm Air Heating and Air Conditioner
Association, or other recognized and acceptable
methods.
Fresh air intakes shall be protected by screens
of corrosion resistant material not larger than 13
mm mesh. Air shall not be re-circulated from
any spaces in which objectionable quantities of
anesthetic gases, toxic gases, flammable
vapors, flying, dust or bacteria laden air are
given off.
Section 5.0 Refrigeration System
5.1
5.2
Where condenser cooling water causes
excessive corrosion, scaling, or obstruction
within the piping or equipment, suitable watertreatment means may be required and piping
used for conveying condenser cooling water
shall be zinc coated. (galvanized copper, or
other corrosion-resistant material acceptable to
the FHA field office of the Chief Underwriter).
Care should be exercised in choosing the
location of fresh air intakes to avoid drawing in
combustible materials to minimize the hazard
from fire in other structures and air conditioning
those listed under Section 8.5.1.
All exposed refrigeration piping located less than
1830 mm above any floor or outside grade shall
be suitably protected to prevent damage to
piping and injury to persons.
Section 7.0 Air Filters
7.1
5.3
Clearance shall be provided for all construction
to permit proper operation, adjustments,
replacement and repair of equipment.
5.4
Suitable means shall be provided for the
collection and disposal of condensate from the
equipment. The condensate drain shall be at
least 19 mm nominal pipe size and shall be
copper, galvanized, steel, or other corrosionresistant materials.
5.5
5.6
Re-circulating air intakes shall be located at
above the floor, except that protected floor inlets
may be permitted under seats in theaters.
When located less than 2,130 mm above the
floor, inlet and outlet openings shall be protected
by a substantial grill or screen, thru the opening
of which 13 mm sphere will not pass.
Air filters shall be of approved types that will not
burn freely or emit large volumes of smoke or
other objectionable products.
Liquid adhesive tanks into which removable
filters are dipped should preferably be located
outside the building or in a separate fire resistive
room.
Liquid adhesive coatings used on air filters shall
have a flash point not lower than 177°C. Air
filters shall have a minimum rating of 60%
filtering efficiency and higher efficiency for
special applications.
Where the cooling coil or air conditioning unit is
located above a living space, or where structural
damage may result from condensate overflow,
an additional waterlight pan of corrosionresistant metal shall be installed beneath the
cooling coil or unit to catch overflow and
separate drain, or one pan with standing
overflow and separate drain maybe provided
with a drain pipe, minimum of 19mm nominal
pipe size, discharging at a point which can be
readily observed. Condensate drains shall not
be directly connected to a plumbing drainage
system.
Filters shall be sized to provide not less than
0.093 m
2 of total face area per 142 lps of air and
shall be readily accessible for cleaning or
replacement.
Section 8.0 Noise Abatement
8.1
Refrigerating piping, with or without insulating
covering shall be exposed to view, excepting for
mechanical protection.
161
As a partial index and guide, the sound level
due to operation of the equipment, as measured
on the 40 decibel weighted network in the center
of conditioned space 914 mm above the floor
shall not be higher than 45 decibels for a
normally furnished room of 50 decibels for an
unfurnished room.
CHAPTER 8— HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
10.5 Cast iron shall conform to American Society for
Testing Materials, designation A-i 36-30 Class B
higher strength gray iron with not less than 206
2 tensile strength.
700 N/rn
Section 9.0 Cold Storage and
Refrigeration
9.1
9.2
9.3
Cold storage shall mean the storage or keeping
of all articles of food at a temperature, not to
exceed —6°C, above 00 in a cold storage
warehouse; cold storage warehouse shall mean
any place artificially cooled at a temperature not
to exceed —6°C in which all articles of food may
be stored or placed for an indefinite period of
time.
10.6 Bushing may be used in fittings when the
reduction is two or more pipe sizes. For single
pipe size reduction, reducing fittings must be
used.
10.7 Pipe bends shall be substantially circular in
section and free from injurious wrinkles, kinds
and creases. They shall not be constructed as
barring corrugated pipe bends made of suitable
material.
Refrigerated Storage shall mean the storage or
keeping of articles of food at a temperature not
to exceed above zero in refrigeration, ice boxes,
and 4°C other similar devices artificially cooled
at a temperature not to exceed 4°C in which
preserved meat, pork, fowl, butter, shrimps,
lobsters, crabs, etc., may be stored or kept.
10.8 Standard pipe size copper or red brass not less
than eighty (80) percent may be used.
10.9 Copper tubing used for refrigerant piping
erected on the premises shall conform to
Materials
Society for Testing
American
designation B-88-33, grades K or L for
dimensions, and shall be absolutely free from
scale and dirt.
An ice plant is closely associated to Cold
Storage and Refrigerated Storage but should be
treated as a Process Plant rather than in an
accessory to a building or buildings.
Section 10.0 Refrigerant Piping, Valves,
Fittings and Related Parts
10.1
10.10 Copper tubing used for refrigerant piping
erected on and 16 mm nominal sizes in the
same standard series as grades K or L of
American Society for testing and Materials
designation B-88-33, shall be considered as
meeting the requirement of Section 8.10.8.
Materials
All materials used in the construction and
installation of Refrigerating System shall be
suitable for the refrigerant used, and no
materials shall be used that will deteriorate due
to the chemical action of the refrigerant or the
oil, or the combination of both.
10.11 Soft annealed copper tubing used for refrigerant
piping erected on the premises shall not be used
in sizes larger than 18 mm nominal size. It shall
conform to grades K or L of American Society
for Testing Materials designation B-88-33.
10.2 Standard weight steel or wrought iron pipe may
be used for Design Working Pressures not
exceeding 1,724.0 kPa, provided lap welded or
seamless pipe is used for sizes larger than 500
mm (iron pipe size) and extra heavy pipe is used
for liquid lines for sizes 38 mm (iron pipe size)
and smaller.
10.12 Rigid metal enclosures shall be provided for soft
annealed copper tubing used for refrigerant
piping erected on the premises, except that
flexible metal enclosures may be used at bends
or terminals if not exceeding 1,830 mm in
length.
10.3 Pipe joints may be screwed, flanged or welded.
Screw joints shall conform to U.S. or R.P.
Standard. Exposed threads shall be tinned or
otherwise coated to inhibit corrosion.
10.13 Threaded joints on copper or brass pipe of
standard pipe size shall be made with extra
heavy brass fittings.
10.14 Joints on annealed copper tubing not exceeding
19 mm in outside diameter may be made with
flared compression fittings or approved type,
provided that all such fitting shall be exposed for
visual inspection.
10.4 d.Valves, flanges and fittings may be made of
cast iron, malleable iron, bronze or brass, and
shall be of the design and material listed by the
manufacturer for the particular refrigerant
service.
162
CHAPTER 8— HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
10.l5Joints on hard drawn copper tubing, if of the
sweated capillary type, may be made with an
alloy having a melting point greater than 538°C
or with solder melting at a point below 240°C but
above 177°C.
d.
10.16 Fittings used in sweated capillary joints shall be
cast red bras or die pressed brass of copper or
wrought brass or copper, or extruded brass or
copper.
10.20 Pipe and Tube Supports
a.
10.17 Soldered joints in pipe or tubing erected on the
premises shall remain mechanically intact when
subjected to a pull apart test equivalent to
pressure of not less than 2,067 kPa gage with a
temperature of not less than 149°C, except that
this requirement shall not apply to soldered
joints in pipe or tubing of 13 mm nominal size or
smaller when used in systems containing not
more than 9.09 kg of refrigerant.
10.19 Stop Valves
a.
Refrigerant piping crossing an open space
which affords passageway in any building
shall not be less than 2,290 mm above the
floor unless against the ceiling of such
space.
b.
Refrigerant piping shall not be placed in
public hallway, lobbies, stairways, elevators
or dumbwaiter shafts, excepting that such
refrigerant piping may pass across a public
hallway, and provided non-ferrous tubing of
25.4 mm nominal outside diameter and less
be contained in a rigid metal pipe.
Refrigerant piping, with or without insulation
covering, shall be exposed to view,
excepting for mechanical protection herein
specified, or when located in the cabinet of a
Unit System.
This does not apply to
refrigerant piping installed outside the
building or in a flue vented to the outer air.
Stop valves shall be installed on all systems
containing more than 9.09 kg but less than
45.45 kg of refrigerant at locations follows:
1.
2.
b.
c.
Each inlet and each outlet pipe of
each compressor.
c.
Each outlet of each liquid receiver.
Stop valves shall be installed on all systems
containing 45.45 kg or more of refrigerant at
location as follows:
1.
Each inlet and each outlet pipe of
each compressor.
2.
Each inlet and each outlet pipe of
each liquid receiver.
3.
Each liquid and each suction branch
header.
All refrigerant piping shall be securely
supported by means of metal hangers,
brackets, straps, clamps or pedestals, in
such manner as to relieve joints of harmful
strains and vibration. The supports shall be
used for no other purpose. Hangers for
refrigerant piping above 22 mm outside
diameter shall not be less than 0.806- cm
2
cross section.
10.21 Location of Refrigerant Piping
10.l8Any evaporator located in an air duct of an air
conditioning system for human comfort shall be
constructed to withstand without leakage a
temperature of 538°C.
a.
Stop valves placed where it is not obvious
what they control shall be suitably labeled.
Numbers may be used to label the valves
provided a key to the numbers is located
near the valves.
10.22 Design and Construction
Stop valves with soft annealed copper
tubing or hard drawn copper tubing 19 mm
nominal size or smaller shall be securely
mounted independent of tubing fastenings
or supports.
163
a.
Every part of a Refrigerating System, except
pressure gauges and control mechanism,
shall be designed, constructed,
and
assembled to withstand the test pressures
specified in Table 8.7, without being
stressed beyond one-third (1/3) of its
ultimate strength.
b.
Equipment
listed
by
a
engineering testing laboratory
follow-up inspection service,
considered
as
conforming
requirements of Section 8.9.21.3.
recognized
having a
shall be
with
the
CHAPTER 8— HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
c.
Refrigerant containing vessels which are not
a part of equipment listed by a recognized
engineering testing laboratory having a
follow-up inspection service shall be
constructed in accordance with the rules of
Chapter 7 (Unified Pressure Vessel).
d.
Every systems, except as provided in
Sections 10,V.d., 11.A and 11.B, shall be
protected by a pressure relief device unless
so constructed that pressure due to fire
conditions will be relieved safely by soldered
joints, lead gaskets, fusible plugs, or their
parts of the system.
discharge capacity determined by test with
the outlet open to the atmosphere and with
a differential pressure across the restraining
member equal to twice the marked pressure
setting of the pressure relief valve.
b.
11.7 Required Capacity
a.
Section 11.0 Pressure Relief Devices
11.1
The minimum required rated discharge
capacity of pressure relief device for a
refrigerant containing vessels shall be
determined by the following formula:
fDL
C
liquid
containing
vessel
pressure
Each
refrigerant and which may be shut off by valves
from all other parts of a refrigerating system,
shall be protected by an approved pressure
relief valve in parallel with a rupture member or
a second approved pressure relief valves if its
3 unless its
gross volume exceeds 0.142 m
diameter does not exceed 152 mm.
Minimum required rated
=
Where C
discharge capacity of the relief device in kg of
air per minute.
D
=
Outside diameter of the vessel
in mm.
11.2 Each pressure vessel having a gross volume of
3 or less, containing liquid refrigerant
0.142 m
and which may be shut off by valves from all
other parts of a refrigerating system, shall be
protected by an approved pressure relief device
or an approved fusible plug.
L
=
Length of the vessel in mm.
f
=
Factor dependent upon kind of
refrigerant as follows:
Value of “f’
Kind of Refrigerant
0.041
Ammonia(NH3)
0.163
Dichlorodifluoromethane,(R-1 2, R-22)
R-134a, R500
11.3 The requirements of Section 10.V.d and 1.1
shall not apply to flooded evaporators located in
a refrigerator cabinet.
11.8 Pressure Setting Test
11.4 Each pressure vessel shall have the Design
Working Pressure stamped thereon if its gross
.
3
volume exceeds 0.142 m
a.
11.5 Compressors operating above 103.35 kPa
gauge and having a displacement exceeding
2.83 m
3 per minute shall be equipped by the
manufacturer with a pressure relief device of
adequate size to prevent rupture of the
compressor, located between the compressor
and stop valve on the discharge side. The
discharge from such relief device may be vented
to the atmosphere or into the low pressure side
of the systems.
The pressure setting of relief devices for
refrigerant containing vessels shall be tested
with the outlet open to the atmosphere and
the relief device shall function at a pressure
not more than ten (10) percent above the
pressure marked thereon, if such marking is
689 kPa or more, or at not more than 6839
kPa above the pressure marked thereon, if
such marking is less than 689 kPa.
11.9 Marking
a.
11.6 Capacity Rating
a.
The rated discharge capacity of rupture
members and discharge piping shall be as
given in Table 8.6.
The rated discharge capacity of a pressure
relief valve, expressed in points of air per
minute shall be one-fifth (1/5) of its
164
All pressure relief valves for refrigerant
containing vessels shall be set and sealed
by the manufacturer. The name or trade of
the manufacturer, the pressure setting
expressed in kPa, the rated discharge
capacity expressed in kilogram of air per
minute, and the minimum equivalent length
CHAPTER 8— HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
of discharge piping that can be attached to
the pressure relief valve without loss of
discharge capacity, shall be cast or stamped
on the device, or on the metal plate
permanently thereto.
b.
a.
Each rupture member for refrigerant
containing pressure vessels shall have cast
or stamped on the device or on a metal
plate of the manufacturer and the bursting
pressure of the rupture member expressed
in Pascal or Kilopascal.
11.10 Installation Requirements
a.
A rupture member may be located between
a pressure relief valve and a pressure
vessel.
b.
No stop valve shall be located between any
automatic pressure relief device and the part
or parts of the system protected thereby,
except when the parallel relief devices
mentioned in Section 10.V.d are so
arranged that only one can be rendered
inoperative at a time for testing or repair
purposes.
c.
All pressure relief devices shall be
connected as nearly as practicable directly
to the pressure vessels or other parts of the
system protected thereby, and shall be
placed above the liquid refrigeration level.
d.
The seats and discs of pressure relief
device for refrigerant containing vessels
shall be constructed of suitable material to
resist refrigerant corrosion.
12.4 Sulfur Dioxide Discharge
a.
Section 12.0 Discharge from Pressure
Relief Devices
12.1
Where ammonia is used, the discharge may
be into a tank of water which shall be used
for no purpose except ammonia absorption.
At least 3.78 liters of fresh water shall be
provided for every 0.45 kg of ammonia in
the system.
The water used shall be
prevented from freezing. The tank shall be
substantially constructed shall be greater
than one-half (1/2) the height. The tank
shall have a hinged cover, or, if of the
enclosed type, shall have vent hole at the
top. All pipe connections shall be through
the top of the tank only, the discharge pipe
from the pressure relief valves shall
discharge the ammonia in the center of the
tank near the bottom.
When sulfur dioxide is used, the discharge
may be into tank of absorptive brine which
shall be used for no purpose except sulfur
dioxide absorption. There shall be 3.378
liters of standard dichromate brine 1.14 kg
sodium dichromate per 3.78 liters for every
0.46 kg of sulfur dioxide in the system.
Brines made with caustic soda or soda ash
may be used in pace of sodium dichromate
provided the quantity and strength give the
equivalent sulfur dioxide absorbing power.
The tank shall be substantially constructed
of not less than 3.15 mm iron or steel. The
tank shall have a hinged cover, or if of the
enclosed type, shall have a vent hole at the
top. All pipe connections shall be through
the top or the tank only. The discharge pipe
from the pressure relief valve shall
discharge the sulfur dioxide in the center of
the tank near the bottom.
Section 13.0 Pressure Limiting Devices
13.1 Pressure limiting devices are required on all
systems containing more than 9.09 kg of
refrigerant and operating above atmospheric
pressure, and on all Water Cooled Systems so
constructed that the compressor or generator is
capable of producing a pressure in excess of the
test pressure.
Pressure relief devices and fusible plus on all
systems containing more than 13.64 kg of
refrigerant, except those used to protect
compressors, shall discharge to the outside of
the building in an approved manner.
12.2 The size of the discharge opening and pipe from
the pressure relief device shall not be less than
the size of the relief device inlet. The discharge
from more than one relief device may be run into
a common header, the area of which shall be
not less than the sum of the areas of the pipes
connected thereto.
13.2
12.3 Ammonia Discharge
165
Pressure limiting devices shall stop the action of
the compressor at a pressure less than ninety
(90) percent of the pressure relief devices
setting but more than ninety (90) percent of the
test pressure given in Table 8.6.
CHAPTER 8— HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
of the refrigerant at 46.11°C. In no case
shall the test pressure be less than 206.7
kPa by gauge.
13.3 Pressure limiting devices shall be connected
between the compressor and the top valve on
the discharge side.
14.7 Posting of Tests
Section 14.0 Test of Refrigerant
Containing Vessels
14.1
a.
Refrigerant containing vessels, the shells of
which have been previously tested under
hydrostatic pressure of not less than one and
one-half times the Design Working Pressure
may be finally tested with pneumatic pressure at
one and one-half times the Design Working
Pressure, instead of hydrostatic pressure.
Section 15.0 Instructions
15.1 All Refrigerating System shall be maintained in a
cleanly manner, free from accumulation of oily
dirt, waste, and other debris and shall be kept
readily accessible at all times.
14.2 Gauges
a.
Liquid level gauge glasses, except those of
the bull’s eye type, shall have automatic
closing shut-off valves, and such glasses
shall be adequately protected against injury.
15.2 It shall be the duty of the person in charge of the
premises on which a refrigerating system
containing more than 9.09 kg of refrigerant is
installed, to place a card conspicuously as near
as practicable to the refrigerant condensing unit
giving directions for the operation of the system,
including precautions to be observed in case of
breakdown or leak as follows:
14.3 Motor Protection
a.
Motors of Refrigerating System shall be
adequately protected against hazardous
overheating under normal or abnormal
operating conditions.
14.4 Tests
a.
b.
Refrigerant containing part of every system
shall be tested and proved tight by the
manufacturer at not less than the minim test
pressure shown in Table 8.7.
Every refrigerant containing part of every
system that is erected on the premises,
devices,
safety
compressors,
except
pressure gauges, and control mechanism,
that are factory tested, shall be tested and
proved tight after complete installation and
before operation at not less than the
minimum pressures shown in Table 8.7.
Instructions for shutting down the system in
case of emergency.
b.
The name, address and day and night
telephone numbers for obtaining service.
c.
The name, address and telephone number
of the municipal inspection department
having jurisdiction and instruction to notify
said department immediately incase of
emergency.
Refrigerant
Name
14.6 Refrigerant not Listed
For refrigerants not listed in Table 8.7, the
Test Pressure for the high pressure side
shall be not less than the saturated vapor
pressure of the refrigerant at 57°C. The test
pressure for the low pressure side shall be
not less than the saturated vapor pressure
a.
Table 8.7
Test Pressures
14.5 Test Medium. No oxygen or any combustible
gas or combustible mixture of gases shall be
fused for testing.
a.
A dated declaration of test, signed by the
installer, shall be mounted in a frame,
protected by glass, and posted in the
machinery room. If an inspector is present
at the tests he shall also sign the
declaration.
Minimum Test
Pressure
Kilopascal
Low
ChemicaiHigh Pres.
Pres.
Side
Formula
Side
3
NH
Ammonia
1
H
4
C
Butane
2
CO
Carbon dioxide
Dichlorodifluoromethane
F
2
CCCI
(Freon-i 2)
CI
(CarreneC
4
F
Dichloromethane 2
166
2 067
620.1
10 355
1 003.5
344.5
6 890
1 619.15
551.2
999.05
344.5
CHAPTER 8— HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
No.1)
(Freon-i 14)
(1 Methylene chloride)
Ammonia
Butane
Carbon dioxide
Dichlorodifluoromethane
(Freon-i 2)
Dichlorotetrafluoromethan
CI
2
CH
3
NI-I
1
H
4
C
2
CO
206.7
206.7
620.1
10 355
206.7
1 033.5
344.5
6 890
F2
2
CCI
1 619.15
999.05
(Freon-114)
CI
C
4
F
2
551.12
Dichioromethane (Carrene
No. 1)
CI
CH
206.7
(Methylene chloride) 2
Dichlorotetrafluoroethane
(Freon-21)
F
2
CHCI
482.3
H2CI
C
2
206.7
Dichloroethylene
Ethane
6
H
2
C
7 579
Ethyl chloride
1
C
5
C2H
413.4
Isobutane
(Ch2)3C
895.7
H
Methyl chloride
CI
3
CH
1 481.35
Methyl formate
HCOOCH 344.5
344.5
each refrigerant condensing unit, and each
refrigerant compressor shall carry a name
plate marked with the manufacturer’s name
and address, identification number, and
name of refrigerant used.
Section 16.0 Helmets
16.1
206.7
344.5
206.7
4 134
344.5
516.75
One mask or helmet shall be required where
amount of Group 2 refrigerants between 45.45
kg and 454.55 kg inclusive, are employed. If
more than 454.55 kg of Group 2 refrigerants are
employed, at least two masks or helmets shall
be required.
16.2 Only complete helmets or masks marked as
approved by the Government Authorized
Agency and suitable for the refrigerant
employed shall be used and they shall be kept
in a suitable cabinet immediately outside the
machinery room or other approved accessible
location.
861.25
344.5
3
Propane
H8
3
C
Sulphur dioxide
2
SO
Trichloromonofluorometha
(Freon-i 1)
F
3
CCI
2 239.25
1171.3
1 446.9
654.55
344.5
206.7
16.3 Canisters or cartridges of helmets or masks
shall be removed immediately after having been
used or the seal broken and in unused, must be
renewed at least once every two (2) years. The
date of filing shall be marked thereon.
15.3 Signs
a.
b.
Section 17.0 Refrigerant Storage
Each Refrigerating System shall be provided
with
an
easily
legible
metal
sign
permanently attached and easily accessible,
indicating thereon the name and address of
the manufacturer or installer, the kind and
total number of kilograms of refrigerant
contained in the system, and field test
pressure applied.
17.1
Note more than 136 kg. Of refrigerant in
approved containers shall be stored in a
machinery room.
17.2 No refrigerant shall be stored in a room in which
less than 9.09 kg are used in the system.
17.3 Refrigerants on the user’s premises in excess of
that permitted in the machinery room shall be
stored in a fireproof shed or room used for no
other purpose.
Systems containing more than 45.45 kg of
refrigerant should be provided with metal
signs having letters of not less than 13 mm
in height designating the main shut-off
valves to each vessel, main steam or
electrical control, remote control switch, and
pressure lifting device. On all exposed high
pressure and low pressure piping in each
room where installed outside the machinery
room, shall be signs as above the name of
the refrigerant and the letters HP or LP.
17.4 Charging and Discharging Refrigerants
a.
When refrigerant is added to a system,
except a unit system containing not more
than 2.73 kg of refrigerant it shall be
charged into the low pressure side of the
system.
No container shall be left
connected to a system while charging or
withdrawing refrigerant.
b.
Refrigerants withdrawn from Refrigerating
System shall only be transferred to
15.4 Marking
a.
Each separately sold refrigerant containing
vessel larger than 0.14 m
3 in gross volume,
167
CHAPTER 8— HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
approved containers. No refrigerant shall be
discharged to a sewer.
c.
operating pressure. Here the refrigerant is at
super-heated vapor state (point 2). Process 2 to
3 is the work of the condenser, whereby heat
contained by the refrigerant is released into the
atmosphere or the cooling medium (Heat Sink)
at constant pressure, thus changing the phase
of the refrigerant from superheated vapor to
saturated liquid, still at the condenser pressure
(pt. 3). Process 3 to 4 is the work of the
expansion valve, whereby liquid refrigerant at
condenser pressure is expanded thus reducing
the pressure to that of the evaporator pressure
(point 4). Liquid and partial amount of vapor
(mixture) refrigerant is admitted into the
evaporator. Process 4 to 1 is the work of the
evaporator, whereby heat from the immediate
surroundings is being absorbed by the
refrigerant, thus changing its phase for liquid
mixture to saturated vapor state (pt. 1). These
complete the ideal refrigeration cycle. In actual
practice however, refrigerant condition at point 1
is usually at superheat condition, and the
condition at point 3 is sub-cooled condition.
The containers from which refrigerants are
discharged into or withdrawn from a
refrigerating system must be carefully
weighed each time they are used for this
purpose, and the containers must not be
filled in excess of the permissible filling
weight for such containers, and such
refrigerants.
Section 18.0 The Fundamentals of Vapor
Compression Refrigeration
18.1
Basic Concepts
If a liquid is introduced into a vessel which is
initially vacuumed, and whose walls are left at a
constant temperature it will at once evaporate.
The latent heat of vaporization will be abstracted
from the series of the vessels, the resulting
cooling effect is the starting point of the
refrigeration cycle.
18.3 Temperature,
Flow Rates
The pressure inside will rise as the liquid
evaporates, until it reaches a certain maximum
value for the temperature. This is the saturation
vapor pressure, no more liquid will evaporate
and of course the cooling effect will cease. Any
further liquid introduced will remain in liquid
state in the bottom of the vessel. If we remove
some of the vapor from the container, by
connecting it to the suction of a pump, the
pressure will tend to fall, and this will cause
more liquid to evaporate. In this way, we can
make the cooling process continuous. We need
a suitable liquid, the refrigerant; a container
where vaporization and cooling can take place,
called the evaporator; and a pump to remove
the vapor, called the compressor. To avoid
continuous consumption of the refrigerant, the
system has to be closed cycle, where the vapor
has to be returned back, in liquid form. So we
use a condenser where liquification can take
place.
Pressures,
Heat
Quantities,
Referring to the pressure-enthalpy diagram, the
ordinate represents the pressure of the
refrigerant in KN/m
2 absolute and the abscissa
its enthalpy in KJ/kg.
The cooling of liquid refrigerant from the
condensing temperature to the temperature of
evaporation is accomplished by the vaporization
of a small amount of liquid downstream of the
expansion valve. Vapor produced in this way is
known as “flash gas”.
The state of mixture of liquid refrigerant and
vapor entering the evaporator is represented on
the diagram by the point 4. Since no heat is
transferred at the expansion valve and no work
is done there, if the mass of liquid that vaporizes
is f kilogram per kilogram of refrigerant
circulated, the following relationship holds:
18.2 Vapor Compression Cycle
Referring to the vapor compression cycle and
the pressure enthalpy diagram, point 1
represent the condition of the refrigerant coming
out of the evaporator at saturated vapor
condition. In Fig. 8.18.2a process 1 to 2 is the
work of the compressor, whereby the saturated
vapor refrigerant is isentropically compressed
until the pressure reaches the condenser
168
CHAPTER 8— HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
Thus:
REFRIGERATION CYCLE
HP VAPOR
(2)
enthalpy of saturated
=
hve
vapor at evaporating pressure, kJ/kg.
(3)
HP LIQUID
EXPANSION
VALUC (A
(1
=
enthalpy of saturated
1
h
liquid at condensing pressure, kJ/kg.
(t
MOTOR
COMPRESSOR
Fig. 81R 2u
Thus
LP GAS
Figure 8182a
enthalpy of saturated
=
hie
liquid at evaporating pressure, kJ/kg.
f
=
sometimes
called
“dryness friction” mass in kg of
refrigerant which vaporizes during
throttling per kg circulated.
Refrigeration Cycle p. 179
3)
enthalpy of saturated
=
vapor at condensing pressure, kJ/kg.
D
3)
Example:
ci)
Ui
ci)33
An air conditioning plant uses Refrigerant 12
and
has evaporating
and condensing
temperatures of 0
C respectively. What will
be the mass of flash gas per kg of refrigerant
circulated?
P
Solution:
p
Referring to Table 8.18.3a, the enthalpies of
saturated Refrigerant 12 are as follows:
Saturated vapour at 0°C hve
187.53 kJ/kg
ENTHALPY
Figure 818.2b
Saturated liquid at 35°C h
10
69.55 kJ/kg.
enthalpy
of mixture
entering
evaporator
enthalpy
of flash
gas
f
enthalpy f
liquid at
evaporating
pressure
+
(1
—
Saturated liquid at 0°C hie
36.05 kJ/kg.
f)
Therefore f
enthalpy
of liquid at
Condens
ng pres
sure
=
=
69.55 36.05
187.53—36.05
—
0.2211
18.4 Refrigerant Effect
=
hvef + hie (1
—
t)
=
10
h
The refrigerant effect per kilogram of refrigerant
in circulation is given by the formula
—
Or
f =
Refrigerating Effect (RE) =
_2)Ei2jfi_.
hve hie
—
eq. 1
(hec— h
)
1
where:
Note: The subscripts I and v denotes liquid and vapor,
respectively.
RE =
Refrigerating effect per kilogram of
circulating refrigerant
enthalpy of refrigerant entering the
hec =
cooling coil
169
CHAPTER 8— HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
1
h
coil
Section 20.0 Energy Conservation for
Ventilating, Refrigeration & Air
Conditioning
enthalpy of refrigerant leaving cooling
=
18.5 Refrigeration CapacityITon of Refrigeration
20.1 To conserve on energy consumption, energy
recovery and saving devices, as recommended
Heating,
Society of
American
by the
Refrigerating and Air Conditioning Engineers
(ASHRAE), Air Conditioning and Refrigeration
Institute (ARI) and/or any internationally
recognized organization in the field of Heating,
Ventilating, Air Conditioning and Refrigeration,
shall be used.
All Refrigerating Capacities shall be expressed
in kilowatts (kw). For 1 Ton of Refrigeration
(TR), this would be equal to 3.517 kilowatts
The work
18.6 Work of compression
the
formula:
by
be
given
compression, shall
—
=
m (hvd
—
of
hve)
where:
Table 8.8
Some Properties of Refrigerant 12
W, = work of compressor
m = mass of refrigerant, kg/s
hvd = enthalpy entering compressor
hve enthalphy leaving compressor
18.7
the ratio of the
Coefficient of Performance
energy removed at the evaporator (refrigerating
effect) to the energy supplied to the compressor.
Hence,
—
COP
h—hk=RE
h d hve
Re’rigeration Cycle p.179
=_i_ KW/KW of refrigeration
COP
=
—
wc
Gas
Entropy
kjlkg K
0.0554
36.05
187.53
0.6966
0.0475
40.69
18966
0.6043
847.7
0.0206
69.55
201.45
0.6839
40
960.7
0.0182
74.59
203.20
0.6825
5
308.6
0.0564
40
8477
0.0212
45
847.7
0.0218
50
847.7
0.0224
c
0
308.6
5
362.6
35
21.1
—
=
Gas
Enthalpy
kjlkg
Gas
Volume
lkg
3
m
-
-
-
-
190.77
0.7081
205.21
0.6950
208.96
0.7078
212.72
0.7196
-
C’)
.
a)
C’
Section 21.0 Montreal Protocol
The ratio of energy
18.8 Energy Efficiency Ratio
removed at the evaporator (refrigerating effect)
to the electrical energy consumed. This shall
conform with the standards set by the
Department of Energy.
EER
Liquid
Enthalpy
kj!kg
Absolute
Pressure
2
KNIm
Temperature
Considering that the Philippines is one of the
signatories in the Montreal Protocol, all
refrigerants banned by the said protocol shall
not be used effective the date set forth by the
same.
21.2 Alternatives suggested by the Air Conditioning
and Refrigeration Institute shall be used in lieu
of the banned refrigerants which destroys the
ozone layer of the earth. It is further encouraged
that extensive researched be made in the field
of Air Conditioning and Refrigeration in order to
save the environment.
Refrigeratinq Effect (kW)
Electricity Consumption (kW)
Section 19.0 Anti-Pollution forHeating,
Ventilating, Refrigeration & Air
Conditioning
19.1 Ventilation systems of dusty industrial buildings
should be provided with appropriate dust
collectors so as not to cause suspended
particulate matter in the ambient air higher than
the quality standards set by the government
agency concerned, and shall conform to Clean
Air Act.
170
CHAPTER 8— HEATING, VENTILATING, REFRIGERATION AND AIRCONDITIONING
Table 8.9
Comparative Performance of Refrigerants at 5°C Condensing at 40°C
F
0
Q
. E
Name of Refrigerant
-D
z
c
0)
1
-
oa
>0)
0
0.
a
W
E
e
•
—
0.0
0
0
OW
.
-
CUJ
coE
W
I-
=
0
0
0
o°)
—
0
>
1)
•5 a
0>
w
Water
5°
0.009
0074
846
2370.0
147.0
62.0
0.1355
92.9
Trichloromonofluorommethane
5°
0.496
1.747
3.52
157.0
0.332
2.12
0.1395
90.2
717
Ammonia
5°
5.160
15.55
3.01
1088.0
0.243
0.214
0.1456
86.4
114
Dichlorotetrafluoroethane
12.7°
1.062
3.373
3.18
106.2
0.122
1.14
0.1484
84.8
12
Dichlorodifluoromethane
5°
3.626
9.607
2.65
115.0
0.047
0.409
0.1502
83.8
113
Trichlorotrifluoromethane
10.4°
0.188
0.783
4.16
129.5
0.654
5.03
0.1511
83.3
Monochlorodifluoromethane
5°
5.838
15.34
2.63
157.8
0.040
0.255
0.1518
82.9
An azeotopic mixture
50
6.678
16.77
2.51
101.0
0.026
0.259
0.1631
77.1
718
11
22
502
171
CHAPTER 9— FIRE PROTECTION & PREVENTION
Chapter 9
FIRE PROTECTION & PREVENTION
This standard also
ordinary combustibles.
applies to storage of commodities which with
their packaging and storage aids would classify
as non-combustibles regardless of storage
height. This standard does not cover unpacked
bulk storage such as grain, coal or similar
commodities.
Section 1.0 General Requirements
1.1
The provision of the Fire Protection
Scope
and Prevention to and govern the following:
—
a.
1.2
1.3
All private or public buildings, facilities,
structures and their premises, constructed,
existing and proposed.
b.
Storage, handling or use of combustible,
flammable, toxic, explosives and other
hazardous materials.
c.
Applications of Fire safety construction,
automatic fire suppressions and fire
protective equipment or systems.
Fire protection system related to certain
commodities introduce hazard different than
contemplated with the above-mentioned General
Storage standard. We have other standards for
the following storage occupancies:
a.
General Safety Requirements. Structure or
Facility the owner of any building, structure,
facility shall install, provide, incorporate, adopt
and maintain under operable and usable
conditions the automatic fire protection devices,
equipment, fire safety construction, and warning
system.
Water density for fire protection for these
0.24
from
varies
particular hazards
gpm/sq.ft. 9.779 (Llmin/m sq.) to 0.68
gpmlsq.ft. (27.7 L/min/m sq.) Water density
requirement for fire protection also depends
on the four classes of commodities, namely
Class I, II, lIlly.
Purpose. The purpose of this standard is to
provide a reasonable degree of protection for life
and property from fire through the installation of
the appropriate type of fire protection for the
different buildings, structures or facilities. Hence
in relation to these standards, all of the owner
and all occupants of the buildings, structures or
facilities shall organize themselves and develop,
implement fire safety programs to include fire
premises,
buildings,
the
in
preventions
notification of the Fire Department Personnel to
the existence of a fire. Fire brigade training and
evaluation of persons and initial fire fighting
utilizing the available fire protection equipment
within their establishment.
Commodity Classification.
Class I Commodity is defined as essentially
non-combustible product on wood pallets, or in
ordinary corrugated cartons with or without
single thickness dividers, or in ordinary paper
wrappings, all on wood pallets. Such product
may have a negligible amount of plastic trims,
such as knobs or handles. Examples of Class
I products are:
Metal products. Metal desk with plastic tops
and trim, electrical coil, electrical devices in
their metal enclosures, dry cell batteries,
stoves, metal cabinets, washers, dryers.
Section 2.0 Indoor General Storage
2.1
Rack storage of Materials over 12 ft. (3.66
m) in height in racks, and storage up to and
including 25 feet (7.62 m) in height and
storage over 25 feet (7.62 m) in height.
Foods. Foods in non-combustible containers,
frozen, foods, meat, fresh fruits, and
vegetables in non-plastic trays.
Application and Scope.
The standard applies to storage, 6.40 m or less
in height, of commodities which with their
packaging and storage aids would classify as
Class II Commodity is defined as Class I
products in slatted wooden crates, solid
172
CHAPTER 9— FIRE PROTECTION & PREVENTION
wooden boxes, or equivalent combustible
packaging
materials on wood
pallets.
Examples of Class I products are:
Class IV Commodity is defined as Class I, II,
Ill products containing an appreciable amount
of plastics in paper board cartons on wood
pallets. Examples of Class IV products are:
Thinly coated fine wire such as radio coil wire
on reels or in cartons, incandescent lamps or
fluorescent bulbs; beer or wine up to 20
percent alcohol, in wood containers; and Class
I product, if small cartons or small packages
placed in ordinary corrugated cartons.
Small appliances, typewriters, and cameras
with plastic parts; plastic-backed tapes and
synthetic fabrics or clothing. An example of
packing material is a metal product in a
foamed plastic cocoon in corrugated cartons.
Class Ill Commodity is defined as wood,
paper, natural fiber cloth, plastic products on
wood pallets, products may be contain a
limited amount of plastics. Wood dressers
with plastic drawer glides, handles, and trim
are examples of a commodity with a limited
amount of plastic.
“Sprinkler System Design Curves for Solid
Pile, Palletized and Bin Box Storage over 12
ft. (3.7 m), and Shelf Storage 12 ft. (3.7 m) to
15 ft. (4.6 m) high, shall be in accordance with
Figure 9-1.1” (6-1.2)
Table 9.1.2 Double row Racks without Solid Shelves, Storage
Higher than 25 ft, Aisles Wider than 4 ft
In-rack sprinklers approximate
vertical spacing at tier nearest
the vertical distance and maximum
horizontal spacing (1)(2)
—
Commodity
Class
Longitudinal
Flue (3)
I, II & III
Maximum
Storage
Height
Fig.
No.
Stagger
Face (4) and (8)
Vertical
Oft
Horizontal
loft
Under honzontal
Barriers
Vertical
Oft
Horizontal
10 ft
Vertical
lOft
orat 15ff. and
5ff
Horizontal
10 ft
Vertical
lOft
Horizontal
10 ft
Vertical
0 ft
Horizontal
10 ft
Vertical
5ff
Horizontal
5 ft
Horizontal barriers at 20 ft. Vertical
lntervals—2 lines of sprinklers
under barriers maximum
horizontal spacing 10 ft. staqece
Vertical
115 ft
Horizontal
ft
Vertical
jF2Oft
Horizontal
5ff
Horizontal barriers at 15 ft Vertical
Intervals —2 lines of sprinklers
under barriers maximum
horizontal spacing 10 ft. staggered
None
7— 10.1 a
30 ft
ceiling
Sprinkler
Operating
Area
No
Ceiling Sprinkler Density
gpm I sq ft (6)
Clearance (5)
Upto lOft (7)
165
286
0.25
0.35
2000 sq ft
Vertical
Horizontal
0 ft
10 ft
None
Vertical
Horizontal
Vertical
Horizontal
Vertical
Horizontal
3Oft
10 ft
‘10 ft
5ff
5ff
7— 10.1 b
Higher
than
Yes
0.25
0.35
7— 10.1 c
30ff
Yes
0.30
035
Yes
0.30
0.40
0.30
0.40
No
0.30
0.40
7—101 g
Yes
0.30
0.40
7— 10.1 h
Yes
0.35
0.45
0.35
0.45
035
0.45
7— 10.1 d
7— 10.1 e
7— 10.1 f
Yes
Higher than
25 ft
2000 sq ft
—
ho
I, II, Ill,
& IV
Vertical
Horizontal
Vertical
Horizontal
‘1Oft
10
lOft
7_ 10.1 i
7
Higherthan
25ff
10 1
Yes
—
For SI Units: 1 ft
173
No
0.3048 m
2000 sq ft
CHAPTER 9— FIRE PROTECTION & PREVENTION
Table 9.1.3
Piling Method
1.On Floor
a. Pyramid
b. Other arrangements such that
no horizontal channels are
formed
c. Tires piled on floor on tread
(See Note 3)
2. Palletized
On side or tread
3. Open Portable Rack Storage
On side or tread
Piling Height
ft
9 to 20
20 to + 30
Expansion foam
See Figure 4—1.2
0.3 plus high
Upto 12
0.6
0.6
0.9
or 0. plus high
expansion foam
9 to 20
20
20
5. Double & Multi-row Fixed
Rack Storage Without
Pallets or Shelves
On side or tread
+
to 30
Upto 12
12 to 20
20
+
to 30
Areas of Application
2 (see Note 1)
ft
High Temp. Head
Ord. Temp. Heads
See NFPA 13, Standard for Installation of Sprinkler Systems
2,000
2,000
0.24
2,000
2,000
0.26
2,000
2.000
0.28
2,000
2,000
0.32
Up to 5
5 + to 7
7 + to 8
8 + to 10
10 + to 12
12 to 30
4. Double & Multi-row Fixed
Rack Storage of Pallets
On side or tread
Sprinkler Discharge Density
gpml ft
2
(See Notes 1 and 2)
3,000
3,000
5,000
(See Note 4)
(See Note 4)
3,000
3,000
5,000
3,000
3,000
See Figure 4— 1.2
0.4 plus 1 line in-rack
sprinklers or 0.3 plus high
expansion foam
3,000
3.000
3,000
3,000
0.3 pIus high
expansion foam
Not
Recommended
3,000
0.6
0.6
0.9
or 0.3 plush high expansion
foam or 0.4 plus 1 line
in-rack sprinklers
5,000
(See Note 4)
(See Note 4)
3,000
3,000
3,000
5,000
3,000
3,000
3,000
0.3 plus high
expansion foam
Not
Recommended
3,000
Notes:
1.
2.
Sprinkler discharge densities and areas of application are based on a maximum clearance of 10 ft (3.1 m) between sprinkler defectors and the
maximum available height of storage.
The densities and areas provided in the table are based on fire tests using standard response; standard orifice (1/2 in.) and large orifice (1 7/32 in.)
sprinklers. In buildings where “old style” sprinkler heads exist, discharge densities shall be increased by 25%. For use of other types of sprinklers,
consult the authority having jurisdiction.
3.
Files not to exceed 25 ft (7.6 m) in direction of wheel holes.
4.
Water supply shall fulfill both requirements.
b.
Fire Protection Standard for Storage of
Rubber Tires. This provision contained in
this standard apply to new facilities for tire
storage and when converting existing
facilities to tire storage occupancy.
c.
Fire Protection Standard for the Storage
of Roll Paper. The purpose of this standard
is to provide a reasonable degree of
protection for the storage of roll paper when
stored in buildings or structures through
installation requirements based upon sound
engineer principles and test data.
Heavy Weight Class. Includes paper board
and paper stock having a basis weight [weight
per 1,000 sq.ft. (93 m.sq.)j of 20 lb. (9.1 kg.) or
greater.
Medium Weight Class. Includes the broad
range of papers having basis weight [weight
per 1,000 sq.ft. (93 m.sq.)] from 10 lb. (4.5 kg.)
to 20 lb (9.1 kg.)
Includes all papers
Light Weight Class.
having basis weight [weight per 1,000 sq.ft.
(93 m.sq.)] less than 10 lb (4.5 kg) and
tissues.
Classification of Roll Paper:
174
CHAPTER 9— FIRE PROTECTION & PREVENTION
Notes:
1.
produce fires that may normally be extinguished
by the quenching and cooling effect of water.
Sprinkle discharge densities and areas
of application are based on a
maximum clearance of 10 ft. (3.1 m)
between sprinkler deflectors and the
maximum available height of storage.
Exposure
The exterior presence of
combustibles which, if ignited, could cause
damage to the storage building or its contents.
—
Fire Wall
A wall designed to prevent the
spread of fire having a fire resistance rating of
not less than four hours and having sufficient
structural stability under fire conditions to allow
collapse of construction on either side without
collapse of wall.
—
2.
The densities and areas provided in
the table are based on fire tests using
response; standard office (1/2 in.) and
large orifice (17/32 in.) sprinklers. In
buildings were “oldstyle” sprinkler
exist, discharge densities shall be
increased by 25%. For used of other
types of sprinklers consult the
authority having jurisdiction.
3.
Files no to exceed 25 ft. (7.6 m) in
direction of wheel holes.
4.
Water supply
requirements.
shall
fulfill
Horizontal Channel Any uninterrupted space
in excess of 1524 m in length between
horizontal layers of stored commodities. Such
channels may be formed by pallets, shelving,
racks or other storage commodities.
Such
channels may be formed by pallets, shelving,
racks or other storage arrangements.
—
both
Non-combustibles
This term designates
commodities, packaging or storage aids which
will not ignite, bum or liberate flammable gases
—
Table 9.1.4 Design Densitvl Area of Arnlication Chart
Heavy Weight
Stora e
hei ht’W
Clearance
Closed Array
Banded or
Unbanded
Banded
Unbanded
Medium Height
Standard Array
Open Array
Open Array
Banded or
Unbanded
Unbanded
Closed Array
Banded or
Unbanded
Banded
Unbanded
10
<5
.3/2000
.3/2000
.3/2000
.3/2000
.3/2000
V
.3/2000
.3/2000
.3/2000
10
>5
.3/2000
.3/2000
.3/2000
.3/2000
.3/2000
.3/2000
.3/2000
.3)2000
.3)2000
Banded
Standard Array
15
<5
.3/2000
.3/2000
.3/2000
.3/2000
.3/2000
.3/2000
.3/2000
.45/2500
.45/2500
15
>5
.3/2000
.3/2000
.3/2000
.3/3000
.3/3500
.3/2000
.3/2500
.45/3000
.45/3000
20
<
5
.3/2000
3/2000
.3/2500
.45/3000
.45/3500
.3/2000
.45(2500
.6/2500
.6/2500
20
>5
.3/2000
.3/2500
.3/3000
.45/3500
.45/4000
.3/2500
.45/3000
.6/3000
.6/3000
25
<
5
.45/2500
.45/3000
.45/3500
.6/2500
.6/3000
.45/3000
.6/3000
.75/2500
.75/2500
NOTE: Densities and/or areas may be interpolated between any 5 ft storage height increment.
SI Units: 1 ft = 0.3048m; 1 gpm/ft
2 = 40.746 (L/min)/m
2
2.2
Definitions
when heated to a temperature of
minutes.
Available Height for Storage
The maximum
height at which commodities, packaging or
storage can be stored above the floor and still
maintain adequate clearance from structural
members and the required clearance below
sprinklers.
7490
for five
—
Packaging
This term designates any
commodity wrapping, cushioning or container.
—
Storage Aids
This term designates
commodity storage devices such as shelves,
pallets, dunnage, decks, platforms, trays, bins,
separators and skids.
—
Ordinary Combustibles This term designates
commodities, packages or storage aids which
have hats of combustion kilojoules per kilogram
similar to wood, cloth or paper and which
—
Warehouse
Any building or area within a
building used principally for the storage of
commodities.
—
175
CHAPTER 9— FIRE PROTECTION & PREVENTION
The maximum number of
Occupant Load
persons that may be allowed to occupy a
particular building, structure, or facility or portion
thereof.
Extra Combustible Materials, which, either by
themselves or in combination with their
packaging, are highly susceptible to ignition and
will contribute to the intensity and rapid spread
of fire.
—
—
Shall
Materials or their
Moderate Combustible
contribute fuel to
will
which
of
either
packaging,
fire.
—
Indicate a mandatory requirement.
—
Indicates a recommendation or that
Should
which is advised but not required.
—
Sprinkler System A sprinkler system, for fire
protection purpose, is an integrated system of
one or more water supplies for fire use,
underground and overhead piping designed in
accordance with fire protection engineering
standards. The portion of the sprinkler system
above ground is a network of specially sized or
hydraulically designed piping installed in building
structure or area, generally overhead, and to
which sprinklers are attached in a systematic
pattern. The valve controlling each system riser
is located in the system riser or its supply piping.
Each sprinkler system includes a device for
actuating alarm when the system is in operation.
The system is usually activated by heat from a
fire and discharges water over the fire area.
Materials and their
Non-Combustibles
packaging which will neither ignite nor support
combustion.
—
—
The word SHALL
requirements.
intended
is
to
indicate
The words IT IS RECOMMENDED indicate
APPROVED refers to
advisory provisions.
approval by the authority having jurisdiction.
Approved. Acceptable to the “Authority having
jurisdiction”.
Authority Having Jurisdiction. The “authority
having jurisdiction” is the organization, office or
individual responsible for approving equipment,
an installation or procedure.
Any building or area within a
Warehouse
building used principally for the storage of
commodities.
—
Fire involving ordinary
Class A Fire
combustible materials such as wood, cloth,
paper, rubber and plastics
—
Class B Fire
gases.
—
2.3
a.
Fire in flammable liquids and
Fire
Class C Fire
electrical equipment.
—
involving
Classification of Storage
energized
Fire involving combustible
Class D Fire
metals, such as magnesium, sodium, potassium,
titanium and other similar metals.
—
Dry Stand Pipe a type of stand pipe system in
which the pipes are not normally filled with
water. Water is introduced into the system thru
Fire Service connections when needed.
—
Type I Storage. Type I storage is that in
which combustible commodities or noninvolving
commodities
combustible
combustible package or storage aids are
stored over 4,550 mm but not more than
6,400 mm high in solid piles or over 3,650
mm but not more than 6,400 mm high in
piles that contain horizontal channels. Minor
quantities of commodities of hazard greater
than ordinary combustibles may be included
without affecting this general classification.
b. Type II Storage. Type II storage is that in
which combustible commodities or noninvolving
commodities
combustible
aids are
storage
combustible packaging or
piles
solid
in
high
mm
4,500
not
over
stored
or not over 3,650 mm high in piles that
contain horizontal channels.
Fire Service An organization or a component
of the Philippine National Police Fire Department
personnel in-charge with the mission of fire
prevention, fire protection.
—
Minor quantities of commodities of hazard
greater than ordinary combustibles may be
included without affecting this general
classification.
A continuous and
Means of Egress
unobstructed route of exit from any point in a
building, structure or facility to a safe public way.
—
176
CHAPTER 9- FIRE PROTECTION & PREVENTION
c. Type Ill Storage. Type II storage is that in
which the stored commodities packaging
and storage aids are non-combustible or
contain only a small concentration of
combustibles which are incapable of
producing a fire that would cause
appreciable damage to the commodities
stored or to non-combustible wall, floor or
roof construction.
Ordinary combustible
commodities in completely sealed noncombustible containers may qualify in this
classification subject to the authority having
jurisdiction. General commodity storage that
is subject to frequent changing and storage
of combustible packaging and storage aids
is excluded from this category.
Section of the warehouse occupied as boiler
room, engine room, or garage shall be cut
off from other sections of the warehouse by
construction having a fire resistance of at
least two hours.
Adequate access shall be provided to all
portions of the premises for fire fighting
purposes.
Frangible wall sections for fire
department or other emergency access or
exit should be considered where doors are
not practical.
b.
2.4 Building Arrangement
a.
Construction. One-storey buildings without
basement storage areas are preferable for
warehouses because of greater efficiency
for fire fighting and salvage operations.
Long narrow buildings provide greater ease
in protection and fire fighting than large
square buildings. Multi-storey buildings may
be subject to the spread of fire from lower to
upper floors and water used on upper floors
may cause damage on lower floors.
Areas. Fire areas of warehouses should be
limited to maintain the total value of the
commodity within reasonable limits yet not
be too restrictive for low value commodities.
Conversely,
value
high
vital
and
commodities. Should be restricted to smaller
areas than for average value commodities
such as found in the usual general
warehouse.
The combustibility of the
commodity and its packaging or storage aids
should be taken into account.
Other
considerations are the difficulty encountered
in fire fighting and salvage operations in
large undivided areas.
Type I and Type II Storage.
When
protected in accordance with this standard,
4,645 m
2 is considered the maximum area
for average value commodities enclosed by
exterior walls or combination of exterior
walls and fire walls. A multi-storey building
having three-hour fire-resistive construction
shall be considered as having each floor a
separate fire area. A multi-storey building of
less than three-hour fire resistance at each
floor shall be considered to be one fire area
with the floor area per level being
cumulative.
Newly-constructed warehouses over one
storey in height should be of not less than
three-hour fire-resistive construction.
Fire wall construction shall be parapet at
least 910 mm above the building roof,
except the parapet may be omitted where
the wall fits tightly to the underside of a fireresistive roof deck.
In buildings having
combustible exterior walls, intersecting fire
walls shall extend at least 1,850 mm in total
length.
Fire walls should preferably be
without openings, but if openings are
necessary they shall be provided with selfclosing or automatic fire doors on each side
of the wall. Such doors shall be suitable for
openings in the particular fire wall.
Type Ill Storage. Warehouses constructed
and protected in accordance with this
standard may be of any reasonable area.
A wall or partition separating the warehouse
from other occupancy shall have fire
resistance rating sufficient to protect the
warehouse from the fire exposure of the
other occupancy. Door openings shall be
equipped with automatic closing fire doors
appropriate for the fire resistance rating of
the wall or partition.
177
c.
Ventilation. Consideration should be given
to the provision of roof vents and curtain
boards, particularly in large one-storey
warehouses where distance to exterior wall
openings makes it difficult to place hose
streams in service.
d.
Protection of Stairways and Shafts.
Stairways and other vertical shafts shall be
enclosed with fire-resistive construction or
sealed at each floor level with construction
CHAPTER 9- FIRE PROTECTION & PREVENTION
means of an exterior balcony, the
door assembly to the stair shall
have a 1-1/2-hour fire protection
rating and shall be self-closing or
by
be
automatic-closing
shall
actuation of a smoke detector.
Openings adjacent to such exterior
balconies shall be protected as
required and as follows:
having the same fire resistance rating as the
floor.
Where stairways are required for the exit of
occupants, such stairways and doors in
interior partitions enclosing stairways shall
be adequately protected.
e.
Stairways and Shaft of High Rise
Proof
Shall
Be
Smoke
Buildings
Enclosures. Smoke proof enclosures shall
be a stair enclosure so designed that the
movement into the smoke proof enclosure of
the product of combustion produced by a fire
occurring in any part of the building shall be
limited and/or eliminated.
2.
Every vestibule shall have a
minimum net area of 16 sq. ft. (1.5
sq.m.) of opening in an exterior
court, yard or public space at least
20 ft. (6.1 m) in width.
3.
Every vestibule shall have a
minimum dimension not less than
the required width of the corridor
leading to it and a minimum
dimension of 72 in. (183 cm) in the
direction of travel.
The smoke proof enclosure may be
accomplished by using natural ventilation,
ventilation
mechanical
using
by
incorporating a vestibule or by pressurizing
the stair enclosure.
A smoke enclosure shall consist of a
continuous stair enclosed from the highest
point to the lowest point by barriers having a
Where a
2-hour fire resistance rating.
2-hour
shall
within
the
it
be
vestibule is used
enclosure and is a part of the smoke proof
enclosure.
g.
Smoke proof
Mechanical Ventilation.
enclosures by mechanical ventilation shall
comply with all of the following:
1.
The door assembly from the building
into the vestibule shall be 1-1/2-hour
fire protection rating and the door
assembly from the vestibule to the
stairway shall have not less than 20minute fire protection rating. The
door to the stairway shall be
designed and installed to minimize
air leakage. The doors shall be selfclosing or shall be automatic-closing
by actuation of a smoke detector
located within 10 ft. (3 m) of the
vestibule door.
2.
Vestibules shall have a minimum
dimension of 44 in. (112 cm) in
width and 72 in. (183 cm) in
direction of exit travel.
3.
The vestibules shall be provided
with not less than one air change
per minute, and the exhaust shall be
150 percent of the supply. Supply
air shall enter and exhaust air shall
discharge from the vestibule through
separate tightly constructed ducts
used only for that purpose. Supply
air shall enter the vestibule within 6
in. (15.2 cm) of the floor level. The
top of the exhaust register shall be
Every smoke enclosure shall discharge into
a public way, into a yard or court having
direct access to a public way or into an exit
passageway. Such exit passageways shall
be without other openings and shall be
separated from the remainder resistance
rating.
f.
Ventilation.
Smoke
Natural
enclosures by natural ventilation
comply with all the following:
1.
proof
shall
Where a vestibule is provided, the
doorway into the vestibule shall be
protected with an approved fire door
assembly having a 1-1/2-hour fire
protection rating and the fire door
assembly from the vestibule to the
stair shall have not less than a 20minute fire protection rating. Doors
shall be designed to minimize air
leakage and shall be self-closing or
by
automatic-closing
shall
be
actuation of a smoke detector within
10 ft (3 m) of the vestibule door.
Where access to the stair is by
178
CHAPTER 9— FIRE PROTECTION & PREVENTION
located not more than 6 in. (15.2
cm) down from the top of the trap
and shall be entirely within the
smoke trap area floors, when in the
open position, shall not obstruct
duct opening. Duct opening may be
provided with controlling dampers if
needed
to
meet the
design
requirements but are not otherwise
required.
h.
4.
The vestibule ceiling shall be at
least 20 in. (50.8cm) higher than the
door opening into the vestibule to
serve as a smoke and heat trap and
to provide an upward moving air
column.
The height may be
decreased
when
justified
by
engineering design and field testing.
5.
The stair shall be provided with a
damper relief opening at the top and
supplied mechanically with sufficient
air to discharge a minimum of 2500
cu. Ft/mm. (70.8 cu rn/mm) through
the relief opening column in the stair
relative to atmosphere with all doors
closed and a minimum of 0.10 inch
water column (25 Pa) difference
between the stair and the vestibule.
shall also be initiated by the following, if
provided.
2.
The building shall be
throughout
by
an
supervised
automatic
system.
of
Mechanical
2.
General evacuation alarm system.
j.
An approved selfStandby Power.
contained generator set to operator
whenever there is a loss of power in a
normal house current shall provide standby
Power
for mechanical ventilation. The
generator shall be in separate room having
a minimum- 1 hour fire resistive occupancy
separation and shall have minimum fuel
supply adequate to operate the equipment
for 2 hours.
k.
Testing. Before the mechanical equipment
is accepted by the authority having
jurisdiction, it shall be tested to confirm that
the mechanical equipment is operating in
compliance with these requirements.
m. Exposure Protection. Adequate protection
against exposure shall be provided where
the warehouse or its contents are subject to
damage from external fire. Depending upon
the severity of the exposure, such protection
should consist of parapet masonry walls
without openings, wire glass in metal framed
windows and/or open sprinklers.
protected
approved
sprinkler
There shall be an engineered
system to pressurize the air
enclosure capable of developing
0.05 in. (12.5 Pa) in addition to the
maximum
anticipated
stack
pressure relative to other parts of
the building measured with all the
enclosure doors closed.
Activation
System.
Water flow signal from a complete
automatic sprinkler system.
Emergency Lighting. The stair shaft and
vestibule shall be provided with emergency
lighting.
Stair
Pressurization.
Smoke
proof
enclosures by stair pressurization shall
comply with all of the following:
1.
1.
Ventilation
n.
Drainage of Floors. Upper floors of multistoried buildings should be made water tight
and provided with floor drainage facilities.
o.
Piles Containing Horizontal Channels
p.
Type I and Type II Storage. Horizontal
channels formed by rack arrangement
should be suitably fire-stopped by means of
barrier at intervals of 7,620 mm unless
additional automatic sprinklers are provided
at intermediate levels to protect the storage.
Horizontal channels of palletized storage
should be perpendicular to the aisle. No
part of such horizontal channels shall be
more than 7,620 mm from an aisle
measured along the length of the channel. It
For both mechanical and pressurized stair
enclosure systems, the activation of the
systems shall be initiated by smoke
detectors and by manual controls accessible
to the fire department. The required system
179
CHAPTER 9— FIRE PROTECTION & PREVENTION
sprinklers opened by a fire.
This is the type of sprinkler
system commonly used and
adaptable to the climate in our
country.
is desirable to eliminate such channels by
fire stopping pallets or by other means.
Section 3.0 Fire Protection Systems
3.1
Standard for the Design and Installation of
Sprinkler System
a.
(b) Deluge System. A system
sprinklers
open
employing
attached to a piping system
connected to a water supply
through which is opened by the
operation of a fire detection
system installed in the same
areas as the sprinklers; when
this valve opens, water flows
into the piping system and
discharges from all sprinklers
attached thereto. This is the
system used in extra hazard
areas like an aircraft hangar,
storage tanks of combustible
liquids, gases and oils, high
substations
voltage
transformers. Foam chemicals
may be incorporated to the
system to be more effective in
fighting class B fires.
General Information
1.
Sprinkler System. A sprinkler
system, for fire protection purposes,
of
integrated
is
system
an
underground and overhead piping
The
standards.
engineering
installation includes a water supply
such as a gravity tank, fire pump,
reservoir or pressure tank and/or
connection by underground piping to
a city main. The portion of the
sprinkler system above ground is a
network of specially sized or
piping
designed
hydraulically
installation in a building, structure or
area to which sprinklers are
connected. The system includes a
controlling valve and alarm devices
when the system is in operation.
The sprinkler head of the system is
usually activated by heat from a fire
and discharges water over the fire
area.
2.
Scope and Purpose. This standard
is the minimum for the installation of
the sprinkler system for buildings,
the character and adequacy of
water supplies to sprinkler systems.
The purpose of this standard is to
provide protection for life and
through
fire
from
property
for
requirements
installation
sprinkler systems based upon
engineering principles, test data,
and field experience.
3.
of
Sprinkler
Classification
Systems. Sprinkler Systems are
classified into different types listed
below:
4.
Classification of Occupancies
(a) Light Hazard Occupancies.
Occupancies where the quantity
and/or combustibility of contents
are low and fire with relatively
low rate of heat release are
hazard
Light
expected.
include
occupancies
occupancies having conditions
Churches, clubs,
similar to:
educational, hospitals, libraries,
except large stock rooms,
or
Nursing
Museums,
Convalescent Homes, Office,
Processing,
Data
including
Residential, Restaurant seating
and
Theaters
areas,
Auditoriums excluding stages
and prosceniums and Unused
attics.
Hazard
(b) Ordinary
Occupancies. There are three
groups of ordinary hazard
occupancies and these are as
follows:
(a) Wet Pipe Systems. A system
employing automatic sprinklers
attached to a piping system
containing water and connected
to a water supply so that water
discharges immediately from
180
CHAPTER 9— FIRE PROTECTION & PREVENTION
1) Ordinary Hazard (Group
1).
Occupancies
where
combustibility
is
low,
quantity of combustible is
moderate,
stockpiles
of
combustibles do not exceed
2,400 mm and fire with
moderate rate of heat
release
are
expected.
Included in this group are
the
following
having
conditions
similar
to:
Automobile
parking
garages,
Bakeries,
Beverages manufacturing,
Canneries, Dairy products
manufacturing
and
processing,
Electronic
plants, Glass and glass
products
manufacturing,
Laundries and Restaurant
service areas.
and
wharves,
Repair
garages,
Tire
manufacturing,
Ware
houses (having moderate to
higher
combustibility
of
contents such as paper,
household furniture, paint
general storage, whiskey,
etc.), and Wood machining.
(c) Extra Hazard Occupancies.
Occupancies where quantity
and combustibility of contents is
very high, and flammable and
combustible liquid, dust, lint or
other materials are present
introducing the probability of
rapidly developing fire with high
rate of heat release.
Extra
hazard
occupancies
are
classified into two groups,
Group 1 and 2.
2) Ordinary Hazard (Group
Occupancies where
2).
quantity and combustibility
of content is moderate.
Stockpiles do not exceed
3,700 mm and fire with
moderate heat release is
expected. Under this group
are the following:
Cereal
mills, Chemical plant
ordinary, Machine shops,
Metal working, Cold storage
warehouses,
Distilleries
Leather
goods
manufacturing,
Libraries,
large stock room areas,
Mercantile,
Printing and
publishing,
Textile
manufacturing,
Tobacco
pro-ducts
manufacturing
and
Wood
products
assembly.
1) Extra Hazard (Group 1).
Include
occupancies
as
described above with little
or
no
flammable
or
combustible
liquids:
combustible hydraulic fluid
used areas, Die casting,
Metal extruding, Plywood
and
particle
board
manufacturing,
Printing
(using inks, with below
37.8°C flash points, Rubber
reclaiming,
compounding,
drying, milling, vulcanizing,
Saw mills, Textile picking,
opening,
blending,
garneting,
carding,
combining
of
cotton
synthetics, wool, shoddy, or
burlap, and Upholstering
with plastic foams.
—
2)
3) Ordinary Hazard (Group
Occupancies where
3).
quantity
and/or
combustibility of contents is
high, and fire of high rate of
release
are
expected.
Included in this group are
following
the
having
conditions similar to: Feed
mills, Pulp and paper mills,
Paper process plants, Piers
181
Extra Hazard (Group 2).
Include occupancies with
moderate to
substantial
amount of flammable or
combustible
liquids
or
where
shielding
of
combustibles is extensive:
Asphalt
saturating,
Flammable liquids spraying,
Flow coating, Mobile home
or
modular
building,
assemblies (where finished
CHAPTER 9— FIRE PROTECTION & PREVENTION
r.
enclosure is present and
has combustible interiors,
Open oil quenching, Solvent
cleaning, Varnish and paint
dipping.
s.
t.
u.
5.
Working plans
Working Plans.
shall be submitted to the authority
having jurisdiction and the office of
the Mechanical Department Building
Official before any equipment is
installed or remodeled. Deviations
from approved plans will require
permission of the authority having
jurisdiction. Working plans shall be
drawn to an indicated scale, on
sheets of uniform size, with plan of
each floor, made so that they can be
easily duplicated and shall show the
following data:
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
I.
m.
n.
o.
p.
q.
v.
w.
x.
y.
z.
aa.
Name of owner and occupant
street
Location,
including
address
Point of compass
Ceiling construction, indicating
ceiling materials, lighting layout,
air duct layout and other
or
obstructions
possible
interference with sprinkler heads
distribution layout.
Full height cross section
Location of fire walls
Location of partitions
Occupancy of each area or
room
Location and size of blind
spaces and closets
small
questionable
Any
no
which
in
enclosures
sprinklers are to be installed.
Size of city main in street, city
main test result.
Other sources of water supply,
with pressure or elevation.
Make, type and nominal orifice
size of sprinkler head.
Temperature rating and location
of high temperature sprinkler
head
Total area protected by each
system on each floor
Number of sprinkler heads on
each riser per floor
Make, type, model and size of
alarm valve
bb.
cc.
dd.
ee.
if.
gg.
182
Make, type, model and size of
deluge valve
Kind and location of alarm bells
Total number of sprinklers on
each alarm valve system
Approximate capacity in liters of
each alarm valve system
Pipe type and schedule of wall
thickness
Nominal pipe size and cutting
length of pipe (or center to
where
dimensions)
center
typical branch lines prevail, it
will be necessary to size only
one line.
Location and size of riser
nipples.
Type of fittings and joints and
location of all welds and bends.
Type and location of hangers
and sleeves
(OS&Y,
All control valves
yoke)
and
screw
outside
indicating valve, check valves,
drain pipes and test pipes.
Size and location of hand hose,
related
and
outlets
hose
equipment.
Underground pipe size, length,
location, weight, material, point
of connections to city main, the
type of valves, meters and valve
pits, and the depth that top of
the pipe is laid below grade.
Provisions of flushing.
When the equipment is to be
installed as an addition to an
existing system, enough of the
shall
be
system
existing
indicated on the plans to make
all conditions clear.
Location of fire department
connections.
Location and detail plan of fire
pumping units and type of pump
foundation,
concrete
drive,
pump suction and discharge
piping, type of controllers, in the
case of electric motor driven
pumps, the electrical power
supply to electric motor must be
connected o an automatic
started emergency generator of
approved capacity to handle fire
pump motor loads in case of
power failure of the local power
supply facilities.
CHAPTER 9— FIRE PROTECTION & PREVENTION
hh. Hydraulic calculation for the
system must be submitted
which
must
indicate
the
following:
Density liter per
min/sq.m. Area of application,
sq.m.; Coverage per sprinkler;
Number of sprinkler calculated;
Total water required, liter per
mm; Total water required for
hose stream, liter/mm; Name of
contractor; Name of designer.
ii. Dry standpipe layout must be
shown in the plans as required
by the Building Code and
Philippine Fire Code P.D. No.
1185.
jj. In case of high rise buildings full
building height must be shown,
fire walls, fire doors, large
unprotected window openings,
and blind spaces, distance to,
construction and occupancy of
exposing buildings which may
affect the effectivity of the
proposed fire protection.
kk. Specification of the sprinkler
system.
6.
General Provisions.
Every automatic
sprinkler systems shall have at least one
automatic water supply.
b.
Water Supply Requirement for Sprinklers
System.
1.
The following tables of water supply
requirements shall be used in
determining the minimum water
supply
requirement
for
light,
ordinary
and
extra
hazard
occupancies.
Table 9.2.2.2(a)
Guide to Water Supply Requirements for
Pipe Schedule Sprinkler System
Occupancy
classification
Residual
Pressure
Required at
the Elevation
of the Highest
Sprinkler
1.03 bar
Light Hazard
Ordinary Hazard
Group 1
1.03 bar or
higher
Ordinary Hazard
Group2
1.03 baror
higher
Approval and Acceptance Test of
Sprinkler
Systems.
Before
installation is started, all aspects of
design, installation and equipment
shall conform in all respects to the
rules, regulations and requirements
of
the
government
agency
concerned, the Fire Code of the
Philippines under RD. 1185, the
Local Building Officials who are
concerned with public safety. For
insurance purposes, the PIRA
(Philippine
Insurance
Rating
Associations).
Acceptable Flow atOuration in
Base of Riser
Minutes
1893
2839 Lpm
30—60 minutes
2650— 3785 Lpm
60— 90 minutes
3217—5678 Lpm
60—90 minutes
—
Ordinary Hazard
Pressure and flow requirements for sprinklers and
hose streams to be determined by authority having
jurisdiction.
Warehouses
Pressure and flow requirements for sprinklers and
hose streams to be determined by authority having
jurisdiction.
High Rise
Building
Pressure and flow requirements for sprinkler and
hose streams to be determined by authority having
jurisdiction.
Extra Hazard
Pressure and flow requirements for sprinklers and
hose streams to be determined by authority having
jurisdiction.
Sprinkler discharged density and
corresponding are a of sprinkler
operation
and
water
supply
requirement
for
hydraulically
designed sprinkler systems. A
hydraulically
designed
sprinkler
system is one in which pipe sizes
are selected on a pressure loss
basis to provide a density LPM
distributed with a reasonable degree
of uniformity over a specified area,
thus permits the selection of pipe
size in accordance with the
characteristics of the water supply
available. The design density and
All test required by this standard
shall be performed by the installer
for the owner in the presence of the
authority having jurisdiction.
Contractor’s materials and test
certificate standard forms shall be
completed and forwarded to the
authority.
3.3
a.
Water Supplies
183
CHAPTER 9— FIRE PROTECTION & PREVENTION
accordance with Table 9.2.2.2(a)
under
9.2.2.2(b) supplied
and
tank
water
from
a
head
positive
water
shall be an acceptable
supply source. Fire pump must be
Underwriters Laboratory (UL) listed
or Factory Mutual approved.
area of application will vary with
occupancy hazard.
Table 9.2.2.2(b)
Table and Design Curves for Determining Density, Area of
Sprinkler Operation and Water Supply Requirements for
Hydraulically Designed Sprinkler System
Sprinkler
(LPM)
Hazard
Classification
Minimum Water Supply
Combined
Inside & Outside
Hose LPM
-
See
See
See
See
Light
Ordinary Group 1
Ordinary Group 2
Ordinary Group 3
Note
Note
Note
Note
30
60-90
60-90
60-120
378.5
946.5
946.5
1,893
1
1
1
1
Duration
in
Minutes
d.
3.
Pressure Tanks
4.
Fire Department Connections
Valves. Types of valves to be used.
All valves on connections to water
supplies and in supply pipes to
sprinklers shall be listed indicating
valves, and shall be 12.05 Bar cold
water or 8.6 Bar saturated steam
pressure rating.
1.
Note 1: The water supply requirement for sprinkler only shall be
calculated from density cuives in Table 9.2.2.2(b).
c.
Sprinkler System may be connected to
the following water supply provided the
capacity and reliability is acceptable.
e.
Gravity Tanks. The capacity and
elevation of the tank fire protection
use and the arrangement of the
supply piping shall provide the
volume and pressure require as
design.
1.
Pumps.
2.
Spacing, Location
Sprinklers
1.
A single automatically
4.1
2
4.830 m
Liaht Hazard
2
Density (Llmin) / m
8.1
10.2
6.1
12.2
14.3
16.3
645
DC
a
372
4000
a
0
oS
5)
0.
C
0
0
5)
00)
0
C
a
3000 I
279
5)
232
C,)
a
C
I
(0)
0
CU
5)
2500
a
0
‘5
5)
186
00
00
0.05
I
0.10
0.25
0.20
Density gpmlsq ft
0.15
0.30
-
For SI Units: 1 sq ft
=
: I gpm/sq ft
2
0.0929 m
184
=
of
Area Limitations. The maximum
floor area to be protected by
sprinklers supplied on each system
riser on any one floor shall be as
follows:
-
2.0
Positions
and
2
40746 (Llmin)/m
0.35
0.40
139
CHAPTER 9— FIRE PROTECTION & PREVENTION
Solid piled storage in excess of
6,400 mm in height or palletized on
rack storage in excess of 3,700 mm
2
in height 3,716 m
25mm
30mm
38mm
50mm
65mm
—
Extra Hazard
f.
Schedule
of
Occupancies
25mm
30 mm
38 mm
50 mm
65mm
75mm
90mm
100mm
sprinklers
sprinklers
sprinklers
sprinklers
sprinklers
2,323 m
2
The total number of sprinklers
above and below the ceiling
exceeds 50 sprinklers shaH be to
150 mm and size thereafter
according to schedule.
Size of Riser. Each system risers shall be
sized to supply all sprinklers on the riser on
any floor as determined by the standard
schedules of pipe sizes listed below the
number of sprinklers on a given pipe size on
one floor shall not exceed the number given
for a given occupancy.
1.
2
4
7
15
50
Light
2. Schedule for Ordinary Hazard
25
30
40
50
65
75
100
125
150
205
Hazard
2 sprinklers
3 sprinklers
5 sprinklers
10 sprinklers
30 sprinklers
60 sprinklers
100 sprinklers
Area limitation given
mm
mm
mm
mm
mm
mm
mm
mm
mm
mm
2 sprinklers
3 sprinklers
5 sprinklers
10 sprinklers
20 sprinklers
40 sprinklers
100 sprinklers
160 sprinklers
275 sprinklers
Area limitation govern
on ordinary hazard
For slid pipe
Exception No. 1:
storage in excess of 4,600 mm in
height or palletized or rack storage
in excess of 3,658 mm. The area
served by any one 205 mm pipe
. Where
2
shall not exceed 3,716 m
single systems serve both storage
and ordinary hazard areas, the
storage area coverage shall not
2 and total area
exceed 3,716 m
.
2
coverage shall not exceed 4,831 m
Branch lines shall not exceed 8
sprinklers on either side of a crossmain.
Exception:
When more than 8
sprinklers are necessary, lines
maybe increased to 9 sprinklers by
making the 2 end lengths 25 mm
and 30 mm respectively, and the
10
standard,
sizes
thereafter
sprinklers maybe placed in branch
lines making the 2 end lengths 25
mm and 30 mm, respectively and
feeding the tenth sprinkler by a 65
mm pipe.
Exception No. 2: When the distance
between sprinklers on the branch
lines exceeds 3,700 mm or the
distance between the branch lines
exceed 3,700 mm, the number of
sprinklers for a given pipe shall be
as follows:
Each area requiring more than 100
sprinklers and without subdividing
partitions (nor necessarily fire walls)
shall be supplied by feed main or
rises sized for ordinary hazard
occupancies.
65mm
75mm
15 sprinklers
30 sprinklers
Branch lines shall not exceed 8
sprinklers on either side of a
crossm am.
When sprinklers are installed above
and below ceiling, such branch lines
shall not exceed 8 sprinklers above
and 8 sprinklers below the ceiling on
either side of the crossmain. Pipe
sizing shall be as follows up to 65
mm.
When sprinklers are installed above
and below a ceiling, the pipe sizing
up to 75 mm shall be as follows:
185
CHAPTER 9— FIRE PROTECTION & PREVENTION
25mm
30 mm
38mm
50mm
65mm
75mm
3.
2
4
7
15
30
60
Extra
Schedule
for
Occupancies
25mm
30mm
38mm
50mm
65mm
75mm
100mm
150mm
205 mm
except
building
construction,
protection area shall not exceed 9.3
2 where the system is hydraulically
m
designed.
sprinklers
sprinklers
sprinklers
sprinklers
sprinklers
sprinklers
h.
Hazard
System Components
1.
1 sprinkler
2 sprinklers
5 sprinklers
8 sprinklers
15 sprinklers
27 sprinklers
55 sprinklers
150 sprinklers
Area limitation applies
(a) Hose stations supply shall not
be connected to any pipe
smaller than 65 mm except for
hydraulically designed loops
and grids. Hose stations supply
pipes maybe connected to a 50
mm source.
Branch lines shall not exceed 6
sprinklers on either side of the
crossmain.
g.
(b) Piping shall be at least 25 mm
for vertical runs.
Protection Area Limitation
1.
(c) Piping shall be 25 mm for
horizontal runs up to 6,096 mm,
30 mm for runs between 6,096
mm and 24.4 meters and 38
mm for runs greater than 24.4
meters.
Light Hazard Occupancy. Under
smooth construction and under
beam and girder construction, the
protection area per sprinkler shall
For
18.6
not exceed
.
2
m
hydraulically
designed
sprinkler
systems, the protected area limit per
sprinkler maybe increased to 20.9
.
2
m
(d) When the pressure at any hose
station exceeds 6.89 Bars
pressure reducing valves shall
be installed at the outlet to
reduce the pressure to 6.89
Bars.
Under open wood joist construction
and for other types of construction,
the protection area per sprinkler
shall not exceed 15.6 m
.
2
2.
2.
Ordinary Hazard Occupancy. For
all types of construction, the
protection area per sprinkler shall
, except for
2
not exceed 12.1 m
buildings
high-piled
for
used
storage, the protection area per
.
2
sprinkler shall not exceed 9.3 m
Hose
Fire
Connection
for
In building of
Department Use.
maybe
light
department
use
attached to wet-pipe sprinkler
systems subject to the following
restrictions:
(a) Sprinklers
shall
be
separate control valves.
under
The maximum spacing between
lines and sprinklers:
Light and
ordinary hazard 4,572 mm except
3,658 mm for high-piled storage.
(b) The minimum size of the riser
shall be 102 mm unless
hydraulic calculations indicate
smaller size satisfy sprinkler and
hose streams demand.
Extra Hazard Occupancies. The
protection area per sprinkler shall
. For any type of
2
not exceed 8.4 m
sprinkler
(c) Each
combined
shall
standpipe
riser
be
equipped with a riser control
—
3.
Internal Fire Hose in Cabinets or
in Hose Reels. 38 mm hose used
for fire purposes maybe connected
to wet sprinkler system only subject
to the following restrictions:
186
CHAPTER 9- FIRE PROTECTION & PREVENTION
valve to permit isolating a riser
without interrupting the supply to
other risers from the same
source of supply.
3.
4.
(c) Stairways.
(d) Vertical opening in buildings.
(e) Service
waiter.
Fire Department Connections.
Fire Department connection shall be
provided to sprinkler system in all
cases. Pipe size shall not be less
than 102 mm for fire engine
connections and to less than 152
mm for fire boat connection. The
fire department connection shall be
on the system side of a check valve
in the water supply piping, or on
wet-pipe system on the system side
of check and alarm valves to the
riser.
(f)
and
dumb
Under roofs or canopies over
outside loading platforms, ducts
or
other
areas
where
combustible are stored
or
handled.
(g) Under ducts and galleries which
are over 1,200 mm wide.
(h) Library stock room.
Sprinkler
System
Standard
Devices.
The Sprinkler System
shall be provided with the following:
(i)
Beneath ducts over 1,200 mm
wide.
(j)
Commercial
equipment
systems.
(a) System main drain.
(b) Auxiliary drain on trapped sections
of pipe.
type
cooing
and
ventilation
(c) Inspector test connections not
less than 25 mm shall be provided
for each system, or for each floor
level.
(k) Electrical components
when
sprinkler protection is provided
in generator and transformer
room, hoods or shields installed
to protect important electrical
equipment from water shall be
non-combustibles.
(d) Pipe sleeves of proper size.
(I)
—
(e) Pipe sway bracing the pipe
hangers conforming to fire code.
Max. Ceiling
Temperature
°C
38
66
107
149
191
246
(f) Water motor alarm gong.
(g) Water flow switches for multistorey building to supervise
system flow on each floor areas.
(h) Valve signs, spare sprinklers and
wrenches in cabinets.
5.
chutes
Sprinklers shall also be required to
the following areas:
3.4
(b) At the opening of the elevator
shaft at each floor level.
187
Sprinkler
Temperature Temperature
Color Code
Rating
Classification
57 to 77
79to 107
121 to 149
163to 191
204 to 249
260 to 302
Ordinary
Uncolored
Intermediate
White
High
Blue
Extra High
Red
Very Extra HighGreen
Ultra High
Orange
Installation of Fire Pumps
a.
(a) Concealed spaces, enclosed
wholly or partially by exposed
combustible construction, as in
walls, floors and ceilings.
Outside
sprinkler protection
against exposure fires.
Standard for the Installation of Fire
Pumps. Only listed fire pumps shall be used
for fire protection service. The adequacy
and dependability of the water source are of
primary importance. Fire pumps shall have
the following rated capacities in LPM or
larger, and are rated at net pressure of 2.75
CHAPTER 9- FIRE PROTECTION & PREVENTION
Table 9.2.5 (a)
Summary of Fire Pump Data
Pump Rating
(LPM)
378
946
1,892
2,839
3,785
5,677
7,570
9,462
11,355
13,247
15,140
Suction
(mm)
51
89
127
152
203
203
254
254
305
305
356
Discharge
(mm)
51
76
127
152
152
203
254
254
305
305
305
Relief
Valve
Discharge
(mm)
Relief
Valve
(mm)
Meter
Device
(mm)
There are two types of standard fire pump
used for the protection service, the
centrifugal and the vertical turbine type,
either horizontal or vertical mounted are
permitted to obtain water on positive suction
The vertical turbine type is
head only.
practically suitable for fire pump service
when the water is located below ground
where it would be difficult to install any other
type of pump below the minimum water
level.
2
Diesel engine drive when used to drive
either centrifugal or vertical turbine fire pump
shall be specifically listed for fire pump
service by the testing laboratories. Engines
shall be acceptable for horse power rating
standard
and
controllers
listed
with
accessories, such as angle gear drive,
governor, over speed shutdown devices,
tachometer, oil pressure gage, temperature
gage, instrument panel, factory wiring,
electrical starter, two (2)sets of batteries with
battery charger, engine cooling exchanger
system, fuel tank, exhaust muffler and
others.
c.
3.5
1
1
4
2
3.6
1 —38
1 —65
2—65
3—65
4—65
6—65
6—65
8—65
12—65
12—65
15—65
51
76
102
150
150
203
303
254
254
305
305
Pressure Maintenance (jockey or make
up) Pumps. Jockey pumps shall have rated
capacities not less than any normal leakage
rate they shall have discharge pressure
sufficient to maintain the desired fire
protection system pressure.
188
Fire Axe with brackets
—
Hydrants Wrench
—
—
—
Coupling spanners for each sized
hose provided, 65 mm
Hose Coupling gaskets for each
size of hose, 65 mm
Standpipe systems are none of the best
internal means for extinguishing fires in
buildings and structures. Even in buildings
equipped with automatic sprinkler systems,
Standpipes are
standpipe is necessary.
required in places such as the upper storey
of high buildings or large areas, low height
buildings, and in other structures where
construction, size of other features limit the
use of hose streams from the exterior.
1.
Hydrants. A sufficient number of hydrants
shall e installed to provide hose streams for
Approved adjustable spray-solid
stream nozzles equipped with
shut-off for each size of hose 65
mm.
—
Dry Stand Pipe and Hose Systems
a.
Outside Protection
a.
Hose, Header
Supply
(mm)
every part of the exterior of each building not
covered by standpipe protection for every
part of each building by the use of lengths of
hose normally attached to the hydrants.
There shall be sufficient hydrants to
concentrate the required fire flow above any
important building protected. An adequate
hose houses shall be placed nearby the
hydrants with standards accessories as
follows:
Bars or more and shall have the following
features standard equipment.
b.
64
89
127
152
203
203
203
203
203
254
254
51
64
127
150
203
203
254
254
305
305
356
38
51
76
102
102
152
152
152
203
203
203
No. & Size
of Hose Valve
(mm)
Class Service
CHAPTER 9- FIRE PROTECTION & PREVENTION
Class I For use by fire department
and those trained in handling heavy
fire streams 65 mm hose.
Minimum water supply for Class
I and Class Ill service shall be
1,893 Lpm for 30 minutes.
Class II
For use primarily by the
buildings occupants until the arrival
of the fire department 38 mm hose.
Minimum water supply for Class
II service shall be 380 Lpm at 30
minutes.
—
—
Class Ill
For use either by fire
department and those trained in
handling heavy hose streams 65
mm or by the building occupants 38
mm hose.
3.7
—
Local Fire Code Requirements
a.
Standpipe system may be wet-type
or dry standpipe.
Standpipe systems for Class I and
Ill services shall be sized for a
minimum flow of 1,893 liter/mm
where more than one standpipe is
required, all common 1,893 liter/mm
for each additional standpipe, the
first standpipe plus 946.5 liter/mm.
for each additional standpipe, the
total not to exceed 9,462 Lpm.
Standpipe not exceeding 23 m in
height shall be at least 100 mm in
size. Standpipe in excess of 23 mm
in height shall be at least 150 mm in
size. Standpipe shall be limited to
84 meters in height and buildings in
excess of 84 meters shall be zoned
accordingly.
Fire Code of the Philippines, which is the
Presidential Decree No. 1185, requires that
the following establishments be protected
with automatic water sprinkler system.
1.
High Rise Buildings.
Structures
or facilities, fifteen (15) meters or
more, measure from the grade level
to the floor of the topmost storey, for
every new or old building.
2.
Places of Assembly.
Stage
equipped with fly galleries gridirons
and rigging for movable theatertype scenery and every enclosed
platform larger than 46.5 square
meters in area.
3.
Educational Building.
(a) Below the floor of exit discharge.
4.
Standpipe systems for Class Ill
service. Each standpipe shall be
sized for a minimum flow of 380
Lpm.
Standpipe and supply piping shall
be either hydraulically designed to
provide the required water supplies
at a minimum residual pressure of
4.5 Bars at the topmost outlet.
General Storage, Boiler, oil furnace
rooms, fuel storage, janitor closets,
maintenance shop including wood
working
and
painting
areas,
laundries, and kitchen, (if these
areas are not separated from the
other parts of building with one hour
fire resistance material rating and all
openings, are not protected with
self-closing door).
(a) Any flexible plan or open
building in which the travel
distance to exits exceeding forty
six (46) meters.
(a) Number of Standpipe.
The
number of hose stations for
Class I, II and Class Ill services
in each building divided by the
walls shall be such that all
portions of each storey of the
building are within 9 meters of a
nozzle attached to not more
than 30.5 meter of hose.
(b) Underground
buildings.
5.
189
and
windowless
Institutional Occupancies and
Residential Areas. Throughout all
hospitals, nursing homes, and
residential custodial care facilities
including hazardous areas.
CHAPTER 9— FIRE PROTECTION & PREVENTION
surface area shall be protected with
fire
automatic
approved
an
extinguishing system.
Occupancies.
Mercantile
protection
sprinkler
Automatic
system shall be installed in all
mercantile occupancies as follows:
6.
3.8
(a) In all one (1) storey building
three
thousand
one
over
hundred ninety four (1,394
sq.m.) in area.
(b) In all buildings over one (1)
storey in height and exceeding
two thousand seven hundred
eighty-seven (2,787 sq.m.) in
gross area.
All
Occupancies.
Business
business occupancy buildings over
15 meters high shall be provided
throughout with automatic sprinkler
protection.
8.
Every
Industrial Occupancies.
high hazard occupancy shall have
automatic protection or such other
protection as maybe appropriate to
the particular hazard.
9.
a.
Portable
Portable Fire Extinguishers.
used by
be
to
extinguishers are appliances
primarily
area,
or
building
a
of
the occupants
for immediate use on small fires. Even in
buildings equipped with automatic sprinkler
system, portable fire extinguishers are
necessary.
b.
The basic types of fire are as follows:
1.
(c) Throughout floors below the
street floor having 232.5 sq. m
when used for the space,
of
handling
or
storage
and
goods
combustible
Merchandise.
7.
Portable Fire Extinguishers
Class A Fires. Are fires in ordinary
combustible materials such as
wood, cloth, paper, rubber and
many plastics.
Extinguishers for protection of Class
A hazards shall be selected from the
following: water types, foam, loaded
stream, and multi-purpose dry
The maximum travel
chemicals.
distance to such extinguishers shall
not exceed 22.8 m.
2.
Class B Fires.
liquids,
flammable
greases.
Are fires in
and
gases
Extinguishers for protection of Class
B hazards shall be selected from the
following halon 1301, halon 1211,
carbon dioxide, dry chemical types,
The
foam and loaded stream.
such
to
distance
travel
maximum
extinguishers shall not exceed 15.25
meters.
Pier and Water Surrounded
Pier aeck must be
Structure.
fire
automatic
with
provided
suppression system protection for
combustible structure and for super
structure, if any.
3.
Plastics
Nitrate
10. Cellulose
existing
and
new
All
(Pyroxylin).
building used for the manufacture or
storage of articles of cellulose
in
(pyroxylin)
plastic
nitrate
quantities exceeding 45 kg.
Are fires which
Class C Fires.
electrical
energized
involve
equipment where electrical nonconductivity of the extinguishing
media is of importance.
Extinguishers for protection of Class
C hazards shall be selected from
the following halon 1301, halon
1211, carbon dioxide and dry
The maximum
chemical types.
extinguishers
such
to
travel distance
shall not exceed 15.25 meters.
11. High Piled Combustible Stock.
Required in each building used for
high piled combustible stock when
the area exceeds 2/3 of the sum of
the basic floor area.
12. Dip Tanks. Dip tanks of over 570
liters capacity of 0.93 sq.m. liquid
190
CHAPTER 9— FIRE PROTECTION & PREVENTION
4.
Class 0 Fires.
Are fires in
combustible
metals,
such
as
magnesium, titanium, zirconium,
sodium and potassium.
Non-combustible
Materials and their
packaging which will neither ignite nor support
combustion.
—
The word shall
requirements.
Extinguishers and
extinguishing
agent for the protection of Class D
hazards shall be of types approved
for use on the specific combustible
metal hazard. The maximum travel
distance to such extinguisher shall
not exceed 23 meters from Class D
hazards.
Extinguisher
Location
and
Mounting. Fire extinguisher should
be installed in plain view, in an
accessible spot, near room exits,
which provide an escape route.
Extinguishers must be located away
from fire hazards, must be installed
so that the top is not more than
1,500 mm above the floor. They
must be easy to reach and remove,
and placed where they will not be
damaged.
indicate
Outdoor storage is
Outdoor Storage.
recognized as standard practice for certain
commodities which, by reason of their bulk,
cannot be ordinarily placed in storage buildings.
Outdoor storage may be preferable to storage in
combustible buildings lacking fire protection, in
the case of materials not subject to undue
damage or deterioration from exposure to the
weather and not particularly susceptible to
ignition by sparks or flying brands.
Where materials, which normally would be
stored in buildings are stored outdoors in
temporary emergencies, it is required special
precaution be taken for their safeguard and that
they be moved to a storage warehouse as soon
as possible.
Purpose
Requirements contained herein are for the
proper handling and safeguarding of storage of
types of commodities of moderate combustible
hazard.
Standards for the storage of noncombustible commodities and those of extra
combustible hazard are excluded, as well as
storage covered by specific standards.
a.
to
Approved refers to approval by the authority
having jurisdiction.
Section 4.0 Outdoor General Storage
4.1
intended
The words it is recommended indicate advisory
provisions.
4.3
5.
is
4.4 Site
a.
Because of the diversity of the materials
handled, no fixed requirements can be
provided to cover all conditions. However,
principles set forth herein will provide a
basis for proper protection of commodities in
storage in the open.
In selecting a site for outdoor storage,
preference shall be given to location having:
1.
Adequate municipal fire and police
protection.
2.
Adequate public water systems with
hydrants
suitably
located
for
protection of the storage.
3.
Adequate all-weather roads for fire
department apparatus response.
4.
Sufficient clear space for buildings
of combustible construction or from
other combustible storage which
might
constitute
an
exposure
hazard.
5.
Absence of flood hazard.
4.2 Definitions
Extra Combustible Materials which, either by
themselves or in combination with their
packaging, are highly susceptible to ignition and
will contribute to the intensity and rapid spread
of fire.
—
Moderate Combustible
Materials or their
packaging, either of which will contribute fuel to
fire.
—
191
CHAPTER 9— FIRE PROTECTION & PREVENTION
Adequate clearance space between
storage piles and any highways and
railroads.
All electrical equipment and installation shall
conform to the provisions of the Philippine
Electrical Code.
Material Piling. Materials shall be stored in unit
piles as low in height and small area as in
consistent with good practice for the material
stored. The maximum height will be determined
by the base of pile and type of packaging,
stability of the material and limit of the effective
reach of hose streams.
All heating equipment shall conform with
prevention
standards.
established
fire
Salamanders, braziers, portable heaters or other
open fires shall not be used.
6.
4.5
Smoking shall be strictly prohibited in any
location where the practice might cause fire.
“No Smoking” signs shall be posted throughout
the storage area except in specific locations
designated as safe for smoking purposes.
Aisles shall be maintained between individual
piles, between piles and buildings and the
boundary line of the storage site. Sufficient
driveways, having a width of at least 4,500 mm
shall be provided to permit the travel of fire
equipment to all portions of the storage area.
Aisles shall be not less than 3,000 mm wide to
reduce danger of spread of fire from pile to pile
and to permit ready access for fire fighting,
emergency removal of materials or for salvage
purposes.
Extra combustible materials will
require wide aisles and roads dependent upon
the height of the pile and the degree of
combustibility. For extra combustible materials,
the width of aisles should be equal to the height
of the pile but not less than 3,000 mm.
4.6
4.7
4.8
4.9
Fences.
The entire property shall be
surrounded in the fence or other suitable means
to prevent access of any unauthorized persons.
Storage and Use of Motor Vehicles Using
Gasoline or Liquefied Petroleum Gas as Fuel.
Vehicles should be garaged in a separate
detached building. Storage and handling of fuel
shall conform to approved standards of
Flammable and Combustible liquids and
approved standards for the storage and
Handling of Liquefied Petroleum Gases. Repair
operations shall be conducted outside the yard
unless separate masonry walled building is
If vehicles are to be greased,
provided.
repaired, painted or otherwise serviced, such
work shall be conducted in conformance with
standards as approved by the authority having
jurisdiction.
Tarpaulins, used for protection of storage
against the weather, shall be of approved flame
proof fabric.
Buildings. Buildings in outside yards shall be
located with as much clear space to open yard
storage as is practicable but shall be not less
than 4,500 mm from open yard piling unless
buildings have blank exterior masonry walls.
Buildings of wood frame construction or
containing hazardous operations shall be at
least 15.2 m from the nearest storage pile; and
explosion vents, blower outlets, etc., not be
directed toward the yard storage.
Coal-fired steam locomotives shall not be
allowed to enter the yard where combustible
material is stored unless the smokestack is
protected by a spark arrester and the ash pan is
protected by screens to prevent hot coals from
escaping.
locomotives
and
Diesel
Oil-fired
steam
locomotives from which glowing particles or
carbon are emitted from the exhaust stacks shall
not be permitted in the yard.
Yard Maintenance and Operations. The entire
storage site shall be kept free from accumulation
of unnecessary combustible materials. Woods
and grass shall be kept down and regular
procedure provided for the periodic clean-up of
the entire area.
4.10 Fire Protection. Provisions shall be made by
some suitable means for promptly notifying the
public fire department or private fire brigade in
case of fire or other emergency.
Adequate lighting shall be provided to allow
supervision of all parts of the storage area at
night.
Provisions shall be made to permit direction of
an adequate number of hose streams on any
pile or portion of the storage area that may be
involved in fire. Unless adequate protection is
provided by a Municipal fire department,
192
CHAPTER 9— FIRE PROTECTION & PREVENTION
sufficient hose and other equipment shall be
kept on hand at the storage property, suitably
housed and provision be made for trained
personnel constantly available to put it into
operation. Monitor nozzles shall be provided at
strategic points where large quantities of highly
combustible materials are stored.
Hydrants and all fire fighting equipment shall be
accessible for use at all times. No temporary
storage shall be allowed to obstruct access to
fire fighting equipment.
4.11 Watch Service. Standard watch service shall
be provided and continuously throughout the
yard and storage area at all times while the yard
is otherwise unoccupied. It is required that there
be some suitable means of supervising the
watchman’s activities to be sure that he makes
his required rounds at regular intervals.
Attention is directed to the value of strategically
placed watch towers in large yards where a
watchman, stationed at a point of vantage, can
keep the entire property under observation.
Such towers shall be connected to the fire alarm
system so that prompt notification of fire may be
given.
7.2
Section 5.0 Anti-Pollution for Standards
for Indoor and Outdoor General Storage
5.1
5.2
Odor-producing material should be stored in
closed storage rooms/warehouses and the
ventilation system of the same should be
provided with appropriate odor control facilities
to preclude odor nuisance in the immediate
vicinity.
7.3
Open yard storage of materials that result in
wind-borne dust problems should be provided
with or water sprinkler systems.
Section 6.0 Standard on Halon 1301 Fire
Extinguished Systems
This section shall not be applicable pursuant to the
Montreal Protocol.
Section 7.0 Fire Prevention Doctrine
7.1
Workers educational programs in fire safety
have become important supplements to welldeveloped fire prevention and inspection
programs, and these include:
193
a.
Regular fire safety audit in every workplace.
b.
Seasonal fire hazard review,
prevention month assessment.
c.
Fire
prevention
awareness shall
be
promoted through pamphlets and posters.
d.
Employers shall teach workers to operates
machines properly and to report any
problems that could cause fire.
e.
Workers shall be empowered to do fire
hazard inspection near machines in their
workplace to supplement supervisor, safety
audit.
f.
A clean workplace program following 5s
standard and emphases (sorting, sweeping,
standardizing, and systemizing) and selfdiscipline.
like
fire
Fire prevention is a term for the many safety
measures used to keep harmful fires from
starting this is being carried out by several
programs in fire safety, like
a.
Laws and specifications.
b.
Inspection of buildings and others company
properties.
c.
Education about fire safety
Education is a vital part of fire prevention
programs because people cause and could
prevent almost all fines. Fire fighters is the most
competent teacher who could reach out to the
level of understanding of children and adult in
communities, schools, homes, industries, ether
indoor and outdoor.
CHAPTER 10- PUMPS
Chapter 10
PUMPS
Section 1.0 General Requirements.
1.1
1.2
1.3
1.4
1.5
air gains entrance due to negative pressure
created by pumping.
Scope. This standard deals with the selection
and installation of pumps supplying water for
domestic, industrials, for private and/or public
fire protection. Items include water supplies,
suction, discharge and auxiliary equipment,
power supplies, electric drive control: internal
control,
and
drive
engine
combustion
.
maintenance
and
operations
acceptance test,
water
system
contain
not
does
This chapter
supply capacity and pressure requirements.
1.6
A shut off valve followed by a check valve shall
be place between the suction of pump and water
mains to prevent any return of water to mains
when pump is stopped.
1.7.1 Overhead Tank Supply. A water tank may be
installed above the roof of the building or by
separate tower for the purpose. Water from the
water mains is pumped to the tank and the
building draws its supply from overhead tank.
Purpose. The purpose of this standard is to
provide a reasonable degree technical know
installation
through
safety,
and
how,
sound
on
based
requirements for pumps
field
and
data
test
engineering principles,
for
the
established
are
Guidelines
experience.
design, installation and maintenance for pumps,
This
drivers and associated equipment.
standard endeavors to continue the excellent
record that has been established by pumps
installation and to meet the needs of changing
technology.
Pumps other than those
Other Pumps.
specified in this standards and having different
design features may be installed when such
pumps are listed by a testing laboratory. Pumps
shall be selected based on the conditions under
which they are to be installed and used. The
pump manufacturer shall be given complete
information concerning the water, or liquid and
power supply characteristics.
a.
Suitable float switch or other devices should
be installed with the tank to stop or start
operation of pump depending on water level
in the tank.
b.
A check valve should be installed between
the pump and tank.
c.
Water tank should be provided with an
overflow pipe, leading to storm drain and a
vent properly protected from insects.
d.
Water tank should be fully covered to keep
out flying debris and to prevent growth of
moss.
e.
For multi-storey buildings, suitable pressure
reducing valves should be supplied to
regulate water pressure for each floor.
The tank is an unfired
Pneumatic Tank.
pressure vessel, initially full of air, into which
water from mains is pumped.
The unit consisting of
Unit Performance.
pumps, driver and controller, shall perform is
compliance with this standard as an entire unit
Certified shop test curves,
when installed.
showing head-capacity and brake horsepower of
the pump shall be furnished by the manufacturer
to the purchaser Engineer.
Installation of pumping equipment to supply
buildings, from existing water supply should only
be allowed if there is always water in the mains
to prevent contamination of water system when
194
a.
A suitable pressure switch should stop
pump when pressure required is attained.
b.
An air volume control device should be
installed to replenish air absorbed by water
under pressure to maintain correct air
volume in tank.
CHAPTER 10
c.
Suitable air valve to take out or
replenish air in tank should be installed
on top of tank.
d.
A tank should be designed for maximum
total
dynamic
pressure
required
multiplied by two to provide for water
hammer. Factor of safety should not be
less than five.
e.
For tanks of 3785 liters or more a
separate air compressor should be
installed to replenish air absorbed by the
water.
f.
For figuring equipment, pipes fittings
and valves, the right pressure ratings
should correspond to total dynamic
head multiplied by two to cover water
hammer effect.
—
PUMPS
caused it to move up thru the piping and out of
the nozzles or opening.
Section 2.0 Definitions
2.4
Hydrodynamics is a general term, and is
generally associated with the science of the
force exerted by water in motion, such as driving
a turbine connected to an electric generator.
2.5
Atmospheric Pressure is due to the weight of
the atmosphere on the earth. At sea level the
atmospheric pressure is 14.7 PSI, or 29.9
inches of Mercury column (Hg), which is
commonly designated as one atmosphere.
Atmospheric pressure diminishes with elevator
above sea level. It is atmospheric pressure on
an open body of water that forces the water up
in pump suction pipe in those cases when a
pump takes suction under lift. (A pump should
always take a suction under water pressure at
atmospheric pressure).
2.6
Vacuum. A perfect vacuum is a space entirely
devoid of gas, liquids or solids. No one has ever
succeeded in exhausting all the air from a
closed vessel (such as suction pipe of a pump).
The word “vacuum” therefore means “partial
vacuum” and is measured by the amount of its
pressure below the prevailing atmospheric
pressure.
2.7
Gauge Pressure (PSIG) is just the term implies
the pressure on a gauge on open air, the gauge
being connected to a closed pipe.
2.8
Absolute Pressure (PSIA) is the sum of the
atmospheric pressure (14.7 PSI or less) and the
gauge pressure (PSIG).
2.9
Pressure Measurements.
Unless otherwise
stated hereafter in this chapter “pressure”
means pressure:
pressure in pounds per
square inch (PSI); head is in feet of water
column (FT); vacuum is in inches of Mercury
(Hg).
One of man’s oldest aids, the pump today ranks
second to the electric motor as the most widely used
industrial machine. Today the U.S. alone draws more
than 200 billion gallons each day from its resources
and pumps move almost every drop. Of this total, an
impressive 80 billions gallons is said to be industry’s
share.
To meet these demands we find as almost confusingly
large variety of available pumps. They range from tiny
adjustable displacement units to giants handling well
over 100,000 gallons per minute. It is neither possible
nor desirable to cover every variation in a concise
practical code such as this: So we’ve made a highly
selective choice of widely used industrial pumps of all
classes and types the pumps you’re likely to run into
your work.
—
2.1
Hydraulic. Hydraulics, or hydromechanics, is
the mechanics of water or other liquid whether
at rest or in motion.
2.2
Hydrostatics is the science of water at rest. A
good example is a gravity tank filled with water
and supplying water to closed valve. Until the
valve is opens, the water is at rest, but its weight
has potential energy and exerts a definite force,
or static rressure against the closed valve.
2.3
No matter how many square inches are covered
by a column of water one foot high, the pressure
is still 0.433 pounds per square inch or 0.433
PSI. 2.31 is the reciprocal of 0.433.
Pressure is force applied to liquids, or force
developed by the weight of the liquids. Pressure
is also called “head”. Pressure is measured in
two ways:
Hydrokinetics is a science of water in motion.
When the valve in the preceding example
opens, the potential energy of static pressure
becomes kinetic energy. The weight of water
a.
195
The number of feet the pressure will
force a column of liquid up to rest. This
____
CHAPTER 10— PUMPS
Differential
(or in meters) of mercury (Hg).
(closed) manometers, may be used for
measuring differences in pressure, such as the
difference between two points in a pipe or
between the total and normal pressure at the
same point in pipe.
is called head in feet, and designated as
h in feet.
b.
The number of pounds of force exerted
This is called
on one square inch.
pounds per square inch and designed
as p (PSI) and/or kilogram per square
).
2
meter (kg/rn
2.12 Pilot Tube. (named for its inventor Pilot) is
used to measure the pressure of water
discharging from a nozzle or flowing in a pipe by
having its open end in the water and the other
end connected to a gauge or manometer. The
tube is generally about one-sixteenth inch in
diameter, bent at right angles, and mounted with
a gauge or manometer connected to the long
end. The short end is held by hand in a hose
stream, nozzle or flowing water. (See figure
10.2.1; 10.2.2; 10.2.3; and 10.2.4).
Bourdon tube -Zero position
2.13 Piezometer is a device set in a pipe to enable a
Bourdon gauge or a manometer attached to the
Piezometer to show the net or normal pressure.
The Piezometer gives a lower pressure by
calming the water entering the gauge or
manometer, thus reducing the fluctuations.
(See figure 10.2.2 and 10.2.3).
Dial Face
Mechanism
Bourdon Gauge-Compound
Fig. 10-1
2.14 Capacity is the rate of flow of liquid measure
per unit of time, usually gallons per minute
(GPM) or liters er minute (LPM).
The two pressure measurements for water
are related in this way:
P (in PSI)
=
0.433 h (in feet)
h (in feet)
=
2.31 p (in PSI)
Friction Loss
2.10 Bourdon Gauge (named for its inventor
Bourdon) consists essentially of a curved tube,
fixed at the open end, with the other (closed)
end free and attached to a lever which is geared
to the indicator needle. When pressure enters
the Bourdon tube, the tube straightens in
proportion to the amount of pressure applied
and this the needle is moved to the pressure
marked on the dial corresponding to the
pressure in the tube. By far most of the gauges
in use are of the bourdon type. (See figure 101).
2.11
UTUb& graduated in tenths
of PSI or in tenths of inch.
Flow
Mercury
P1
Piezameters
P2
Fig. 10.2
Differential Manometer (U-Tube) for Measuring the fiction,
Loss between two points on a level pipe
2.15 Suction Lifts (Hs) exist when the total suction is
below atmospheric pressure. Suction lift, as
determined on test, is the reading of a liquid
manometer at the suction of the pump,
converted to the feet of liquid, and referred to
datum, minus the velocity head at the point of
gage attachment.
Manometer (open type) is a gauge in the form
of a glass U-tube one leg of which is open to the
atmosphere, or a straight tube one end of which
is open to the atmosphere. The height to which
a column of water would rise in the open tube is
a measure of the feet of head or pressure in the
pipe to which the manometer is connected. To
eliminate unwisely tube heights and freezing at
ordinary water freezing temperatures, mercury is
generally used, the graduations being in inches
2.16 Suction Head (Hs) exists when the total suction
head is above atmospheric pressure. Suction
head, as determined on test, is a reading of a
gage at the suction flange of the pump
converted to feet or meter of liquid and referred
196
CHAPTER 10— PUMPS
to datum, plus the velocity head at the point of
gage attachment.
Where:
2.17 Velocity Head (Hv) is figured from the average
velocity (v) obtained by dividing the discharge in
cubic feet per second (cfs) or cubic meter
second (cms) by the actual area of the pipe
cross section in square feet or square meter and
determined at the point of the gage connection.
It is expressed by the formula:
hv
0
Tube
2.19 Total Head is the measure of the energy
increase per pound imparted to the liquid by the
pump and is therefore the algebraic difference
between the total discharge head and the total
suction lift exists, is the sum of the total
discharge head and total suction lift; and when
suction head exists, the total head is the total
discharge head minus the total suction head.
Fig. 10-3
Differential Manometer (U-Tube) for Measuring velocity
pressure by means of the difference between total pressure
(from Pitot Tube) normal pressure (from Piezometer)
2.20 Net Positive Suction Head (NPSH) is the total
suction head in feet or in meter of liquid absolute
determined at the suction flange and referred to
datum, less the vapor pressure of the liquid in
feet or meter absolute.
Normal or Net Pressure
“EQ
GL— Total Pressure
“>itji,
Pilot Tube
Total Pressure Normal or Net Pressure
2.21
Velocity Pressure
=
Centrifugal Pump.
A pump in which the
pressure is developed principally by the action
of centrifugal force.
2.22 End Suction Pump. A single suction pump
having its suction nozzle on the opposite side of
the casing from the stuffing box and having the
face of the suction nozzle perpendicular to the
longitudinal axis of the shaft.
Fig. 10-4
Total Pressure Normal or Net Pressure
V is average velocity in the
pipe in feet per second.
2.18 Total Discharge Head (Hd) is the reading of a
pressure gage at the discharge of the pump,
converted to feet of liquid and referred to datum,
plus velocity head at the point of gage
attachment.
.j:0t
Piezometer
V
2
2g
and
Velocity Prese
Piezometer
=
g is the acceleration due
to gravity = 32.17 feet
per second square.
Velocity Pressure
2.23 In Line Pump. A centrifugal pump whose drive
unit is supported by the pump having its suction
and discharge flanges on approximately the
same center.
PITOT TUBE HELD BY HAND
-
PLAYPIPE
2.24 Horizontal Pump.
A pump with the shaft
normally in a horizontal position.
FIRE HYDRANT
2.25 Horizontal Split-Case Pump.
A centrifugal
pump characterized by a housing which is split
parallel to the shaft.
PITOT TUBE
HELD BY HAND
2.26 Vertical Shaft Turbine Pump. A centrifugal
pump with one or more impellers discharging
into one or more bowls and a vertical eductor or
Fig. 10-5
197
__________________
CHAPTER 10— PUMPS
They are available as horizontal o
vertical pumps, single or multi-stage
for wide flow ranges.
column pipe used to connect the bowls to the
discharge head on which the pump driver is
mounted.
2.27 A Booster Pump is a pump that takes suction
from a public service main or private-use water
system for the purpose of increasing the
effective water pressure.
Diffuser-type centrifugals find many
uses as multi-stage high-pressure
units. Originally more efficient than
volute-type pumps, today efficiency
of both types is about equal.
Diffuser
2.28 Submersible Pump. A vertical turbine pump
with the pump and motor closed coupled and
designed to be installed underground, as in the
case of the deepwell pump.
Mixed-Flow
]
2.29 Aquifer. An underground formation that
contains sufficient saturated permeable material
to yield significant quantities of water.
called
often
Axial-flow units,
propeller pumps, develop most of
their head by lifting action of vanes,
are usually vertical, and best suited
for low heads, large capacities.
Axial-Flow
A test
2.30 Aquifer Performance Analysis.
amount of
designed
to
the
determine
underground water available in a given field and
proper well spacing to avoid interference in that
field. Basically, test results provide information
storage
transmissibility
and
concerning
coefficient (available volume of water) of the
aquifer.
For clear liquids, turbine pumps,
either horizontal or vertical, fill a
need between other centrifugal and
usual rotary designs. They are lowto-medium-capacity high head.
Turbine or
Regenerative
Gear pumps consist of two or more
gears (spur, single-or double-helical
teeth) while vane pumps have a
series of vanes, blades or buckets
turned by a single rotor. This rotary
class also includes lobe or shuttleblock designs.
Gear Vane
A timber, concrete, or masonry
2.31 Wet Pit.
enclosure having a screened inlet kept partially
filled with water by an open body of water such
as pond, lake, or streams.
2.32 Ground Water. That water which is available
driven
into water-bearing
from
a well,
subsurface strata (aquifer).
Cam and piston rotaries, like most
types in this class, are positivedisplacement units, giving steady
discharge flow along with screwtype pumps, and related designs,
they handle a wide range of nonabrasive viscous liquids.
Cam and
Piston
2.33 Static Water Level. The level with respect to
the pump, of the body of water from which it
takes suction when the pump is not in operation.
2.34 Pumping Water Level. The level, with respect
to the pump, of the body of water from which it
takes suction, when the pump is in operation.
Direct-Acting
]
2.35 Draw-Down. The vertical difference between
the pumping water level and the static water
level.
Power
Section 3.0 Pumps
THESE QUICK GUIDES TO THE WORLD OF PUMPS
SHOW THE MAJOR CLASSES AND TYPES IN USE
TODAY:
Volute
CrankFlywheel
The majority of centrifugal pumps
built today are the volute type.
198
Mixed-flow centrifugals pumps are
ideal for low head large-capacity
applications. Usually vertical, they
have a single-inlet impeller. Some
horizontal units are built.
Old standbys for years, direct
acting pumps now are available in
many designs for handling cold or
hot water, oil, and a wide range of
industrial liquids of many types.
Power pumps are driven from
outside through a crankshaft or
Capacities range
other device.
from very low to medium flows, at
pressure up to 15,000 psi, (1033.5
bars), or higher.
Crank-and-flywheel pumps are one
form of reciprocating power pump,
so designated to distinguish them
from power pumps using, for
example, an eccentric as drive
mechanism.
CHAPTER 10— PUMPS
A.
CENTRIFUGAL:
1.
AXIAL FLOW
Mixed Flow
Semi-open impeller
2.
Radial Flow
Self-printing
3.
Perpheral
— — — —
Non-printing
Jet (eductor)
Gas lift
B. SPECIAL EFFECTS
Hydraulic Ram
Electromagnetic
simplex
C. RECIPROCATING:
1. Piston
Plunger
tiiplex
multiplex
2 Diaphragm
D. ROTARY
199
CHAPTER 10— PUMPS
3.1
Pump Classification
3.2
Centrifugal Pumps. A centrifugal is a machine
which the pumping action is accomplished by
imparting kinetic energy to the fluid by a high
speed revolving impeller with vanes and
subsequently converting this kinetic energy into
pressure energy either by passing the fluid thru
a volute casing or thru diffuser vanes.
By Inlet Geometry Commonly applied to
to a
turbo machines and rotary pumps
lesser extent; which describes the basic
geometry of the section entry of the pump.
Refers to the design (or
By Layout
possible) position of the pump, shaft access,
such as horizontal, vertical or inclined This
indicates the mounting requirements (most
likely floor space). A further classification is
applicable for turbo machines, particularly
where the casing halves divide for
disassembly.
Generally describes the
By Mounting
design method of mounting the pump and
applies but not necessarily always specified
for all pump types.
Basically is the description
By Operation
of the design duty of the stand by pump
like for the example, air pump, source pump,
stand by pump, auxiliary pump, etc. But this
does not necessarily follow that the use of
such a pump is restricted to the specified
operation.
This specific
By Liquid Handled
description indicates that the pump can
handle a particular type or types of fluid or
product like chemicals and other corrosive
liquids.
By Material This indicate the type of the
pump whose material of construction
particularly the wetted parts is suitable for
handling chemically active or corrosive
fluids.
This specifies the method of
By Drive
drive intended or applicable for the pump as
spiced in the design mounting area
limitations or other requirements to use, for
example, electric motor, engine (gas or
diesel), integral (electric) motor, magnet
drive, manual drive, turbo driven, shaftdriven, etc.
Pumps of this type
Submersible Pumps
are of sufficient importance to warrant a
classification of their own, representing the
type of pump with integral electric motor,
which can be immersed in the product being
handled. They can be subdivided into
various categories according to intended
duty, for example deepwell, borehole, etc.
and by the form of canned motor.
—
,
-
.
After the conversion is accomplished, the fluid is
discharged from the machine.
—
When the kinetic energy is converted to
pressure energy by means of the volute shape
of the casing, the pumps are called volute
centrifugal pumps. When the conversion of
kinetic energy to pressure energy occurs in the
passage of the fluid thru stationary diffusers
vanes, the pumps are called diffuser centrifugal
pumps.
-
The radial type of impeller is characterized by
rather long narrow passages for the water. The
ratio of outside impeller diameter D2 to impeller
eye diameter Dl is approximately 2.
—
The Francis type of impeller is characterized by
wider passages for the water and the ratio of D2
toDi is about 1.5.
—
The mixed flow type of impeller is characterized
by a mixed flow velocity vector, which naturally
has a horizontal component along the shaft as
well as a vertical component perpendicular to
the shaft. The ratio of D2 to Dl is slightly over
unity.
—
The axial or propeller type of impeller has a ratio
of D2 to Dl equal to unity. The pumping action
is accomplished by lifting of the water by the
pitch of the blades of propeller as it revolves. As
this type of impeller has no guidance for the flow
of water, it cannot operate with suction lift. The
impeller or propeller is generally immersed in the
liquid.
a.
—
Classification of Centrifugal Pumps
Centrifugal pumps can be classified, as follows;
b.
the common form of
By Geometry
classification of turbo machines, and
centrifugal pumps in particular, from the
shape of the casing.
-
Basic Parts of a Centrifugal Pump.
Imparts velocity to the liquid,
Impeller
resulting from centrifugal force as the
impeller is rotated.
—
200
CHAPTER 10— PUMPS
Casing
Gives direction to the flow from
the impeller and converts this velocity
energy into pressure energy which is usually
measured in feet of head.
defined as the speed in rpm at which a
given impeller would operate if reduced
proportionately in size, as to deliver a rated
capacity of 1 GPM against a total dynamic
head of one foot. The visualization of this
definition, however has no practical value for
specific speed if used to classify impellers
as to their type or proportions and as a
means of predicting other important pump
characteristics, such as the suction limitation
of the pump.
—
Shaft
Transmit power from the driver to
the impeller.
—
Stuffing Box This is a means of throttling
the leakage which would otherwise occur at
the point of entry of the shaft into the casing.
Usually not a separate part, but rather made
up of a group of small details.
—
1.
Packing This is the most common
means of throttling the leakage
between the inside and outside of
the casing.
2.
Gland To position and adjust the
packing pressure.
3.
Seal Gage (also called water-seal
of lantern ring)
Provides passage
to distribute the sealing medium
uniformly around the portion of the
shaft that passes through the
stuffing box. This is very essential
when suction lift conditions prevail
to seal against in leakage of air.
The effect of suction lift on a centrifugal
pump is related to its head, capacity and
speed. Impellers for high head usually have
low specific speeds. Impellers for low heads
usually have high specific speeds. The
specific speed is found to be very valuable
criterion in determining the permissible
maximum suction lift, or minimum suction
head. Abnormally high suction lifts beyond
the suction rating of the pump, usually
causes serious reductions in capacity and
efficiency, which often leads to serious
trouble from vibration and cavitation. For a
head and capacity, a pump of low specific
speed will operate safely with greater
suction lift than one of the higher specific
speed. Pumps at the higher speeds without
proper suction conditions often cause
serious trouble from vibration, noise and
pitting.
—
—
—
4.
Mechanical Seal.
Provides a
mechanical sealing arrangement
that takes the place of the packing.
Basically, it has one surface rotating
with the shaft and one stationary
face. The minute close clearance
between these two faces prevents
leakage of liquid out or air in.
The equation for specific speed of a centrifugal
pump is expressed as follows:
Specific Speed,
Ns=
Shaft Sleeve
Protects the shaft where it
passes through the stuffing box. Usually
used in pumps with packing but often
eliminated
mechanical
if
seals
are
employed.
NQ
(H)
314
—
where:
Ns
specific speed of pump in
RPM
Ns
=
rated speed of pump,
RPM
=
pump capacity in GPM
Q
(Note: 1 gallon = 3.785 liters)
=
H
pump head per stage, feet
Stage (Note: 3.28 ft = 1 meter)
Wearing
Rings
Keeps
internal
recirculation down to a minimum. Having
these rings as replaceable wearing surfaces
permits renewal of clearances to keep pump
efficiencies high. On small types only one
ring is used in the casing and on larger
sizes, companion rings are used in the
casing and on the impeller.
—
c.
=
For double suction pumps the Q value is
determined by dividing the given capacity by 2,
which is then substituted in the formula.
Specific Speed. Specific speed is a type
characteristic of centrifugal pumps and is
For multi-stage pumps the H value is determined
by dividing the total head by the number of
201
CHAPTER 10— PUMPS
stages available from the pump. This is so
because each impeller contributes a definite
value of head of the total developed by the
Pump.
Qi
Law b2
Affinity Laws for Centrifugal Pumps:
±ii
2
H
The mathematical relationship between these several
variables, that is; capacity, head power at constant
impeller diameter and speed.
1
_w
2
KW
Law al
=
Ni
N
Law a2
=
H
2
Law a3
_Yi
2
KW
b.
=
_Q.i
2
D
=
2
D
Where:
at constant impeller diameter
2
Q
=
Law b3
These relationships are expressed as follows;
a.
P
1
2
D
=
2
Q
Qi
Hi
=
Dl
Q2
H2
=
=
=
Capacity
head at Ni RPM or with impeller
Diameter
Capacity
head at N2 RPM or with impeller
Diameter
D2
__Ni
2
N
Law al applies to the Centrifugal, Angle Flow,
Propeller, Peripheral, Rotary and Reciprocating
pumps.
__Ni
2
N
Law a2 and a3 apply to Centrifugal, Angle Flow, Mixed
Flow, Propeller and Peripheral pumps.
At constant impeller speed
Law bi, b2 and b3 apply to Centrifugal Pumps only.
Law bi
202
CHAPTER 10— PUMPS
Parallel and Series Operation of Centrifugal Pumps
shape between the screw
threads and is displaced axially
as the rotor threads mesh.
Pumps are installed in parallel to satisfy variable
pumping requirements to maintain pump operation at
peak efficiency and optimum power consumption. With
this installation program plant shutdown are easily
scheduled without disrupting critical operations.
(d) Vane Pumps. This type consists
of one rotor in a casing machined
eccentrically to the drive shaft. The
rotor is fitted with a series of vanes,
blades or buckets which follow the
bore
of the
casing
thereby
displacing
liquid
with
each
revolution of the drive shaft. Vane
pumps may have swinging vanes or
sliding vanes.
Similarly, multiple pumps in series may be used when
liquid must be delivered at high heads.
3.3
Rotary Pumps. A rotary pump is a positive
displacement pump consisting of a fixed casing
containing gears, cams, screws, vanes,
plungers or similar elements actuated by
rotation of the drive shaft.
a.
The rotary pump combines the constant
discharge characteristic of the centrifugal type
with the positive discharge characteristic of the
reciprocating pump.
The flow from a
reciprocating pump is pulsating whereas the
flow from many rotary types of pump is constant.
The positive discharge characteristic including
reciprocating pump prevents the operation of
these pumps against a closed discharge unless
an automatic unloader is provided to bypass the
discharge with the suction well. Rotary pumps
are capable of handling only a clean solution
essentially free of solids and particularly
adopted to handling liquids of high viscosities,
such as heavy fuel oil, paint, etc.
Types
1. Cam and Piston Pumps. This type
consists of an eccentrically bored
cam, rotated by a shaft concentric in
a cylindrically bored casing, with an
abutment or follower so arranged
that with each rotation of the drive
shaft a positive quantity of liquid is
displaced from the space between
the cam and follow and the pump
casing.
2.
Gear Pumps. This type consists of
two or more gears, operating in
3.4
closely fitted casing so arranged
that when the gear teeth unmeet on
one side liquids fills the space
between the gear teeth and is
carried around in the tooth space to
the opposite side and displaced as
the teeth mesh again. There are
two types of gear pumps:
Reciprocating Pumps. A reciprocating pump is
a positive displacement unit wherein the
pumping action is accomplished by the forward
and backward movement of a piston or plunger
inside a cylinder usually provided with valves.
Piston types are used for low pressure light duty
or intermittent service. Less expensive than the
plunger design, but cannot handle gritty liquids.
Plunger types are used for high pressure heavy
duty or continuous service.
(a) External gear pumps have all
the gear rotors cut externally.
The gears maybe spur, single
helical or double helical.
Suitable for gritty and foreign material service,
and more expensive than the piston design.
a.
(b) Internal gear pumps have one
rotor with internally cut gear
teeth meshing with an externally
cut gear idler. Pumps of this
type are made with or without a
crescent shaped partition.
Types of Reciprocating Pumps
1.
(c) Screw Pumps.
This type
consists of one, two or three
screw rotors so arranged that as
the rotors turn liquid fills the
203
Direct Acting Steam Pumps. This
type has a steam cylinder with no
lap on valves, a water cylinder and
a common piston rod. As there is
no lap, the steam is admitted
throughout the length of the stroke,
hence the pressure volume diagram
of the steam end is rectangle.
Consequently, the water end flow
diagram will also be a rectangle with
CHAPTER 10— PUMPS
besides the piston and cylinder and various
forms of valves used.
40
1.
Its function is to
Air Chamber.
due to the nature
flow
the
smoothen
of flow of the liquid from such type
of pump. The size of air chamber
required depends on the type of
pump, and generally on the
pressure and length of pipe line. Air
chamber can be placed either on
the suction side or discharge side of
the piping installation.
2.
Pressure Relief Valve. This should
be installed on the discharge side
between pump and any other valve.
3.
Foot Valve and Strainer. These
should also be installed at the end
of the suction pipe. The foot-valve
should be of a size at least equal to
the size of the suction pipe. The
clear area of the strainer should be
at least three times the area of the
suction pipe in order to minimize
head loss at this point.
1301
hr
90
80
70
60
50
RATED SPEED
Fig. 10.9 Chart showing effect of speed change on
centrifugal pump performance.
constant
flow
discharge
the
throughout the length of the stroke
and going down to zero value at the
instant or reversal of the piston at
the end of each stroke.
2.
Flywheel
and
Crank
Reciprocating Pump. This type is
crosscompound,
by
driven
ion
triple-expans
or
compound,
steam engines. In large sizes such
units are known as pumping
engines.
3.
Power Driven Pumps. This type
receives its forward and backward
motion of the piston and plunger
from the rotary motion of a revolving
crankshaft by means of a crank and
connecting rod.
where:
Q
Q
=
+
=
actual volume of liquid discharged
true piston or plunger displacement
Q includes all losses of capacity due to leakage
past piston packing, stuffing boxes, and valves
and also that loss due to delayed closing of
All losses of capacity given in
valves.
percentage of the displacement are referred to
as slip (1 eq). In new pumps the slip is of the
order of 2%.
Reciprocating pumps can be single
They
acting or double acting.
etc.,
triplex,
can be simplex, duplex,
water
of
number
the
depending on
cylinders on the machine. Due to
the manner of operation of directacting steam pumps, practically
direct-acting steam
almost all
pumps are built double acting.
b.
Head, Capacity, Efficiency. The total head
as defined for centrifugal pumps also
applies to reciprocating pumps. It is general
practice of manufacturers of reciprocating
pumps to state capacities in terms of piston
or plunger displacement without deduction
for the piston rod area or slippage.
Volumetric efficiency is defined as:
c.
—
3.5
Deep Well Pumps
a.
Accessories of Reciprocating Pumps.
The reciprocating pumps need some
accessories for better and safe operation
204
Deep well may be divided into plunger or
reciprocating, turbine, ejector-centrifugal
types and air lifts.
CHAPTER 10— PUMPS
1.
2.
3.
Plunger Pumps. Modern plunger
pumps are refinement of the old
hand pumps that have played such
an important role in country-home
and small town water supply from
wells. A ball valve, plunger, and
check valves are used in this pump.
In operation, only the plunger
moves. When the plunger is raised
a vacuum is created below it, and
water flows in through the check
valve to fill the void. When the
plunger is lowered, the check valve
close and traps the fluid in the
pump, and it is forced up through
the valve in the plunger, to be lifted
on the next upward stroke of the
plunger.
combines a single-stage centrifugal
pump at the top of the well and an
ejector or jet located down in the
water. This is best suited where the
lift is 7.6 meters or over the
capacities up to 190 liters per
minute net discharge. The amount
of water required to flow down the
pressure pipe for jet operation
increases as the lift from well-water
level to the pump increases.
4.
Turbine Pumps.
These pumps
represent the application of vertical
centrifugal pumps to deep well
service and are built for heads up to
305 meters and for capacities up to
26 495 liters per minute.
The
turbine pump includes two principal
parts; the head, comprising a
vertical driving motor, discharge
connection, and step bearing, and
the pumping unit. The pump unit is
that part installed under the pump
head below the surface of the
ground.
It comprises the pump
column, shafting, and pump stages,
the latter consisting of the bowls
and impellers. A type of turbine
pump wherein the motor is below
the turbine bowls is called the
submersible motor pumps. In this
set-up the propelling shaft is very
short and the usually long, smalldiameter
motor
operates
submerged at all times in the well
water. However, the liquid pumped
does not come in contact with the
electrical parts on motor bearings,
as these are enclosed in an oil-filled
case with a mercury seal where the
shaft passes through at the top.
The turbine and the submersible
motor form a compact unit that is
attached to an supported by the
discharge pipe.
b.
E
Air Lifts.
Another method of
pumping wells is by air lifts with
compressed air being admitted to
the well to lift water to the surface.
For successful operation of the
system, the discharge pipe must
have its lower end submerged in the
well water.
The amount of
submergence before air is admitted
will vary from 70 per cent for 6.1
meter lifts to 40 per cent for a 214
meter lift. When air is admitted to a
well, the water recedes from the
level of static head to the bottom of
the discharge pipes. This displaced
column of liquid rises up the
discharge pipe and as the air flow
continues, it enters the pipe,
aerating the water and lowering the
specific gravity of the mixture.
Pressure in the well is momentarily
decreased and then increased as
the bottom end of the pipe is
uncovered and covered. The cycle
repeats rapidly, producing a nearly
constant flow from the top of the
discharge pipe.
Horsepower
and
Brake
Water
Horsepower. The theoretical amount of
energy necessary to raise a given volume of
fluid (Q) from a lower to a higher elevation
is:
=
QWH
=
foot
-
pounds
where:
Ejector-Centrifugal Pump. A type
of deep well pump that has come
into wide use for small capacities
Q
=
volume of fluid in gallons
W
=
weight of fluid in lb. per gallon
H
205
=
vertical distance between elevations in
feet
CHAPTER 10— PUMPS
There are several metric methods of specifying
pressure. The most basic is the newton per
square meter (N1m
). However, it is convenient
2
to use the term pascal (Pa) which represent one
Newton per square meter; by doing this pascal
is associated with pressure and not with stress.
Segments of the fluid power industry prefer the
term bar, which is equal to 100 000 pascals.
The following relationship can be used for
converting to metric:
The water horsepower is:
WHP
When Q is expressed in
gpm
QWH
33 000
=
or
WHP
for water at standard
temperature i.e., one gallon
of water weighs 8.334 lbs.
QH
3960
100 000 Pa
100 000 N1m
2
=
14.5 psi
1 inch mercury (at 60°F)
1 bar
For liquids other than water or for water at other
temperatures than the standard:
WHP
Q x H x Sp. Gr.
3 960
=
=
Q x 2.31 P
3 960
1 psi
When pumping any liquid having a specific
gravity against a pressure (P) in psi, the WHP
equation becomes:
1 gpm
2.31 P
WHP
=
=
QxSp.qr. x
3 960
Qx2.31f
3960
=
0.034 bars
=
2
0.07045 kgcm
Customarily, fluid flow has been expressed as
gallons per minute for liquids and cubic feet per
minute for gases. For liquid in metric units,
cubic meter per minute or liters per minute are
usable quantities. The following relationships
represent relative magnitudes.
QP
1 714
=
=
Other manufacturers of fluids power equipment
prefer to express gauge pressure in units of
kg!cm2. For basis of comparison
Where specific gravity of the liquid considered at
the corresponding temperature.
When pressure, expressed in psi, is considered
instead of head, H, in feet, for water H 2.31 P
for standard conditions.
WHP
=
=
=
3.785 liters/mm.
0.003785 m
/min.
3
=
Section 5.0 Metric Pump Formula
Sp.Gr.
5.1
QP
1 714
Theoretical Power in Kilowatts
Power, KW
Due to the various losses in the flow of water
thru pump, the friction in piping both suction and
discharge, and due to turbulence of the water
and the energy, to create the velocity of flow, the
brake horsepower required by the pump is much
greater than the water horsepower. The relation
Qx WxH
6 130.25
=
where:
Q
W
H
=
=
=
pump capacity in liters/mm.
weight of fluid in kgs/liter
total head in meters
is:
For cold water, W
BHP
=
WHP
efficiency
1 kg per liter
hence eq (1) becomes
Section 4.0 Fluid Power Metrication
4.1
=
KW
If the hydraulic or pneumatic circuitry is
designed within metric parameters, equipment
and other components such as valves, cylinders
or gages must have mounting that are
compatible with metric fasteners, such as bolts
and clevis pins.
=
QxH
6 130.25
and for other fluids, the equation has to be
multiplied by their corresponding specific
gravities.
206
CHAPTER 10— PUMPS
thus, KW = QxHxsp. gravity
6 130.25
5.2
= 22217.14x380
3960
Actual Power Required, KWa
2 132 hp
c.
Exam pie 1
KWa =
-
By the metric pump formula
KWT
efficiency
Power =
Water from a reservoir is pumped over a hill
through a pipe 3 ft. in diameter, and a
pressure of 30 psi is maintained at the
summit, where the pipe is 300 ft above the
reservoir. The quantity pumped is 49.5 cfs,
and by reason of friction in the pump pipe
there is 10 ft of head loss between the
reservoir and the summit. What amount of
energy must be furnished the water each
second by the pump?
Q
H
KWt
By the energy equation (English):
Q = 49.5 cfs = V x area
V = 49.5 (0.7854 x 9)
*VeiHead_
Pressure head
= 0.7ft
= 30 psi x 2.31
= 69.3 ft.
Elevation
Head Loss
= 300 ft
=
lOft
= 69.3 + 0.7
= 380 ft
+
Power =
+
300
velocity
3960
=
1 589.86 KW
1 589.89 KW÷ 0.746
=
2 131.2 hp
Q x (P x 10)
6130.25
kw
Qx
sp.
PxlO
Gr. x sp. Gr.
6130.25
+
Example 2:
If the pump in example 1 is working against a pressure
of 11.6 kg/cm indicated by a gage installed at the
discharge side approximately 1 meter from the pump,
how much power is required?
10
380 ft x 49.5 cfs x 62.4 lbs/cu.ft
550 fps
By the English Unit pump formula
QxH
84091.9 x 115.9
6 130.25
= Q x P x 10
6130.25
Solution:
= 2130hp(2134hp)
Whp =
=
When pumping any liquid having a specific gravity,
(sp. gr.) against a pressure in kg/cm, eq. (5) will
remain the same since
*Total head of the pump = pressure head
head + elevation + head loss (if any)
b.
22 217.14 gpm x 3.785
84 091.9 liters/mm.
380 ft ÷ 3.28 ft/meter
115.9 meter
Hence, Power (theoretical) =
V
2
2g
49
64.4
Energy of pump =
QxH
6 130.25
When pressure, expressed in kg/cm, is considered
instead of Head in meters H
P in kg/cm x 10
m/kg/cm for water at normal (standard) condition.
7 fps
—
—
=
=
=
=
Check:
Solution:
a.
= 380ft
Power =
Qx(PxlO)
6130.25
—
Q = 49.5 cfsx448.83
= 22 217.14 gpm
207
=
84 091.90x(11.6x 10)
6130.25
=
1591.2kw
CHAPTER 10- PUMPS
rechecked periodically. To facilitate accurate
field alignment, most manufacturers either do
not dowel the pumps or drivers on the base
plate before shipment, or at most dowel the
pump only.
Summary of Pump Data. The following table
10.5.3(a) indicates the minimum recommended
pipe sizes for the following pump with rated
capacities:
5.3
TabJe 10.5.3(a) Summary of Pump Data
Pump
Rating
gpmL/min
Minimum Pipe Sizes (Nominal)
Relief
Water
Relief Valve Valve
Meter
Suction
Discharge
in.* (mm) in. (mm)
(95)
25
50(189)
1 (25)
100 (379)
2 (50)
150 (568)
200 (757)
1 (25)
in. (mm)
3/4 (19)
Discharge Device
in.
in. (mm)
34
1 (25)
1 1/2(38)
1 1/2 (38)
2 (50)
2 1/2 (65) 2 1/2 (65)
3 (75)
3 (75)
2 (50)
2 (50)
2 1/2 (65)
2 1/2 (65)
250 (946)
3 1/2 (89) 3 (75)
2 (50)
2 1/2 (65)
300(1136)
4(100)
4(100)
21/2(65)
31/2(89)
82
400 (1514)
450 (1703)
500 (1892)
4 (100)
5 (127)
5 (127)
4 (100)
5 (127)
5 (127)
3 (75)
3 (75)
3 (75)
5 (127)
5 (127)
5 (127)
4 (100)
4 (100)
5 (127)
6 (150)
6 (150)
8 (200)
8 (200)
10 (250)
4
4
6
6
6
(100)
(100)
(150)
(150)
(150)
6 (150)
6 (150)
8 (200)
8 (200)
10 (250)
5
5
6
8
8
10
12
12
12
14
14
6
8
8
8
8
8
(150)
(200)
(200)
(200)
(200)
(200)
10
12
12
14
14
14
750
1000
1250
1500
2000
(2839)
(3785)
(4731)
(5677)
(7570)
6 (150)
6 (150)
8 (200)
8 (200)
10 (250)
2500
3000
3500
4000
4500
5000
(9462)
(11355)
(13247)
(15140)
(17032)
(18925)
10
12
12
14
16
16
*
5.4
(250)
(300)
(300)
(355)
(400)
(400)
2 (50)
(250)
(300)
(300)
(300)
(355)
(355)
(250)
(300)
(300)
(355)
(355)
(355)
A flexible coupling should not be used to
compensate for misalignment of the pump and
driver shafts. The purpose of the coupling is to
compensate for temperature changes and to
permit end movement of the shafts without
interference with each other while transmitting
power from the driver to the pump.
2(50)
1 1/4(32)
1 1/2 (38) 1 1/4(32)
After the pump and driver unit has been placed
on the foundation the coupling halves should be
The coupling should not be
disconnected.
reconnected until the alignment operations have
been completed.
(65)
3 (75)
3 (75)
(89)
There are two forms of misalignment between
the pump shaft and the driver shaft, as follows:
(127)
(127)
(150)
(200)
(200)
8 (200)
8 (200)
10 (250)
10 (250)
10 (250)
10 (250)
Pump Foundation and Alignment. Pumps
should be installed properly. It is very important
that the pump and driver be provided with rigid
foundation, and the pump and driver are
aligned.
A substantial foundation is important in
maintaining alignment. The foundation should
preferably be made of reinforced concrete.
5.6
If pumps and drivers were shipped from the
factory with both machines mounted on a
common base plate, they were accurately
aligned before shipment. All base plates are
flexible to some extent and, therefore, must not
be relied upon to maintain the factory alignment.
Realignment is necessary after the complete
unit has been leveled on the foundation and
again after the grout has set and foundation
The alignment
bolts have been tightened.
should be checked after the unit is piped and
shafts with axes
Angular misalignment
concentric but not parallel.
b.
shafts with axes
Parallel misalignment
parallel but not concentric.
—
—
The faces of the coupling halves should be
spaced far enough apart so that they cannot
strike each other when the driver rotor is moved
hard over toward the pump. Due allowance
should be made for wear of the thrust bearings.
The necessary tools for an approximate check
of the alignment of a flexible coupling are a
straight edge and a taper gage or a set of feeler
gases.
Actual pump flange may be less than pump size.
5.5
a.
A check for angular alignment is made by
inserting the taper gage or feelers at four points
between the coupling faces and comparing the
distance between the faces at four points
spaced at 90-degree intervals around the
coupling. The unit will be in angular alignment
when the measurements show that the coupling
faces are the same distance apart at all points.
A check for parallel alignment is made by
placing a straight edge across both coupling
rims at the top, bottom, and at both sides. The
unit will be in parallel alignment when the
straight edge rests evenly on the coupling rim at
all positions. Allowance may be necessary for
temperature changes and for coupling halves
that are not of the same outside diameter. Care
208
CHAPTER 10— PUMPS
must be taken to have the straight edge parallel
to the axis of the shafts.
the piping of the unit has been connected, the
alignment should be checked again.
Angular and parallel misalignment are corrected
by means of shims under the motor mounting
feet. After each change, it is necessary to
recheck the alignment of the coupling halves.
Adjustment in one direction may disturb
adjustments already made in another direction.
It should not be necessary to adjust the shims
under the pump.
The permissible amount of misalignment will
vary with the type of pump and driver.
The best method for putting the coupling halves
in final accurate alignment is by the use of a dial
indicator.
The direction of driver rotation should be
checked to make certain that it matches that of
the pump.
The corresponding direction of
rotation of the pump is indicated by a direction
arrow on the pump casing.
The coupling halves can then be reconnected.
With the pump properly primed, the unit then
should be operated under normal operating
conditions until temperatures have stabilized. It
then should be shut down and immediately
checked again for alignment of the coupling. All
alignment checks must be made with coupling
halves disconnected and again after they are
reconnected.
Checking Angular Alignment
After the units have been in operation for about
10 hours or three months, the coupling halves
should be given a final check for misalignment
caused by pipe or temperature strains. If the
alignment is correct, both pump and driver
should be dowelled to the base plate. Dowel
location
is
very
important
and
the
manufacturer’s instructions should be obtained,
especially if the unit is subjected to temperature.
When the alignment is correct, the foundation
bolts should be tightened evenly but not too
firmly. The unit can then be grouted to the
foundation.
The base plate should be
completely filled with grout, and it is desirable to
grout the leveling pieces, shims, or wedges in
place.
Foundation bolts should not be fully
tightened until the grout is hardened, usually
about 48 hours after pouring.
After the grout has set and the foundation bolts
have been properly tightened, the unit should be
checked for parallel and angular alignment and,
if necessary, corrective measures taken. After
209
CHAPTER 10— PUMPS
Right
Wrong
Water Lubricated
Oil Lubricated
Open Une nheii pump
Su,face dwcharge
Th,eaded column and bowls
Enclosed bee shOP pump
Underground discharge
Flanged Column and bonds
Fig. 10.4.7(b) Right and Wrong Pump Suctions
The unit should be checked periodically for
alignment. If the unit does not stay in line after
being properly installed the following are
possible causes:
(a) Settling, seasoning, or springing of the
foundation, Pipe strains distorting or shifting
the machine.
(b) Wear of the bearings.
(c) Springing of the base plate by heat from an
adjacent steam pipe or from a steam
turbine.
Fig. 10.4.7(a) Ilustration of Water-Lubricated
and Oil-Lubricated Shaft Pumps
(d) Shifting of the building structure due to
variable loading or other causes.
It may be necessary to slightly readjust the
alignment, from time to time, whi!e the unit and
foundation are new.
5.7
Satisfactory
Supervision of Installation.
operation of vertical turbine-type pumps is
dependent to a large extent upon careful and
correct installation of the unit; therefore, it is
recommended that this work be done under the
direction of a representative of the pump
manufacturer.
5.8
Pump Maintenance and Servicing. Pumps
like any other machines requires regular
The
preventive main-tenance and servicing.
following tables are the list of the possible
causes of the troubles, may be experienced
during and after the installation of the pumping
system.
210
Water Lubricated
Oil Lubricated
Open Line shaft pump
Surface discharge
Threaded column and
bowl
Enclosed line shaft pump
Underground discharge
Flanged columns and
bowl
CHAPTER 11 -PIPING
Chapter 11
PIPING
Section 1.0 Scope
has a plate so suspended that the reverse flow aids
gravity in forcing the plate against a seat, shutting off
reverse flow.
This
chapter
provides
general
and
specific
requirements not only for plant or building piping but
also for general piping installations. It includes Power
Piping System Design and pipe color coding for safety
and proper fluid identification in the system.
Compression Joint
A multi-piece joint with cu
shaped threaded nuts which, when tightened
compress tapered sleeves so that they form joint 0:
the periphery of the tubing they connect.
—
Section 2.0 Definitions
Cross-Over A small fitting with a double offset, ol
shaped like the letter U with the ends turned out. It is
only made in small sizes and used to pass the flow of
one pipe past another when the pipes are in the same
plane.
—
Pipe and Tube The fundamental difference between
pipe and tube is the dimensional standard to which
each is manufactured. A pipe is a tube with a round
cross section conforming to the dimensional
requirements for nominal pipe size as tabulated in
table for Pipe Schedules.
—
Expansion Loop A large radius bend in a pipe line
to absorb longitudinal expansion in the pipe line due to
heat.
—
A tube is a hollow product of round or any other cross
section having a continuous periphery. Round tube
size maybe specified with respect to any two, but not
all three of the following: outside diameter or bell at
one end into which the plain or spigot end of another
piece is inserted when laying. The joint is then made
tight by cement, oakum, lead, or rubber caulked into
the bell around the spigot.
Black Pipe
—
Galvanized Pipe
resist corrosion.
Steel pipe coated with zinc to
—
Gate Valve A valve employing a gate, often wedgeshaped, allowing fluid to flow when the gate is lifted
from the seat. Such valves have less resistance to
flow than globe valves.
—
Steel pipe that has not been galvanized.
Globe Valve
One with a somewhat globe shaped
body with a manually raised or lowered disc which
when closed rests on a seat so as to prevent passage
of a fluid.
-
Bell and Spigot Joint The commonly used joint in
cast-iron pipe. Each piece is made with an enlarged
diameter or bell at one end into which the plain or
spigot end of another piece is inserted when laying.
The joint is then made tight by cement, oakum, lead,
or rubber caulked into the bell around the spigot.
—
Bull Head Tee
than the run.
—
Header A large pipe or drum into which each of a
group of boilers is connected. Also used for a large
pipe from which a number of smaller ones are
connected in line and from the side of the large pipe.
—
A tee the branch of which is larger
Malleable Iron
Cast iron heat-treated to reduce its
brittleness. The process enables the materials to
stretch to some extent and to stand greater shock.
—
Butt Weld Joint A welded pipe joint made with the
ends of the two pipes butting each other, the weld
being around the periphery. (Refer to Chapter 14
Section 14.3.3.27 no. 6)
—
Manifold A fitting with a number of branches in line
connecting to smaller pipes. Used largely as an
interchangeable term with header.
—
Carbon Steel Pipe
Steel pipe which owes its
properties chiefly to the carbon which it contains.
—
Medium Pressure
When applied to valves and
fittings, implies they are suitable for a working
pressure of from 862 to 1207 kPa. (125 to 175 psi).
—
Check Valve
A valve designed to allow a fluid to
pass through in one direction only. A common type
—
211
CHAPTER 11
-
PIPING
Mill Length Also known as random length. Run-ofmill pipe is 4 880 mm to 6 000 mm in length. Some
pipe are made in double lengths of 9 150 to 10 675
mm.
3.3
All piping to headers shall come from below
rack.
3.4
All piping from headers shall go up above rack.
Relief Valve One designed to open automatically to
relieve excess pressure.
3.5
All piping above or below racks shall
supported on separate racks.
Run A length of pipe made of more than one piece
of pipe; a portion of a fitting having its ends in line or
nearly so, in contradistinction to the branch or side
opening, as of a tee.
3.6
All piping should run with slight inclination for
drainage of main headers.
3.7
All piping on racks shall have a sufficient
spacing for pipe or chain wrenches so that any
single line can be altered without disturbing the
rest of the piping on rack.
3.8
All piping 63.5 mm and above shall be flanged
while smaller sizes can be screwed.
3.9
On long headers a pair of flanges shall be
provided for every three lengths of 6 000 mm of
pipes 63.5 mm and above.
—
—
—
Saddle Flange A flange curved to fit a boiler or tank
and to be attached to a threaded pipe. The flange is
riveted or welded to the boiler or tank.
—
A flange screwed on the pipe
Screwed Flange
is
which it connecting to an adjoining pipe.
—
Socket Weld A joint made by use of a socket weld
fitting which has a prepared female end or socket for
insertion of the pipe to which it is welded.
—
be
3.10 On long headers a pair of unions shall be
provided for every three lengths of 6 000 mm of
pipes smaller than 63.5 mm.
Formerly used to designate
Standard Pressure
cast-iron flanges, fittings, valves, etc., suitable for a
maximum working steam pressure of 862 kPa.
—
3.11 All piping subject to varying temperature shall be
provided with expansion joints or expansion
loops to take care of expansion.
An elbow with male thread on one
Street Elbow
end, and female thread on the other end.
—
Uniform heating of a structure or
Stress-Relieving
portion thereof to a sufficient temperature to relieve
the major portion of the residual stresses, followed by
uniform cooling.
3.12 No galvanized piping shall be used for steam.
Iron refined to a plastic state in a
Wrought Iron
puddling furnace. It is characterized by the presence
of about 3 percent of slag irregularly mixed with pure
iron and about 0.5 percent carbon.
3.14 All piping shall be clamped by “U” bolts or
clamps to supporting racks except steam piping.
—
3.13 No piping material shall be used that is easily
corroded by material passing thru.
—
3.15 Piping supports shall be placed on a 3 000 mm
intervals or less.
Wrought Pipe This term refers to both wrought steel
and wrought iron. Wrought in this sense means
worked, as in the process of forming furnace-welded
pipe from skelp, or seamless pipe from plates or
billets. The expression wrought pipe is thus used as a
distinction from cast pipe. When wrought-iron pipe is
referred to, it should be designated by its complete
name.
—
3.16 All steam piping shall be supported on rollers or
sliding support for expansion.
3.17 All piping carrying pressure shall be of sufficient
bursting strength for the pressure applied. A
minimum factor of safety of 4 for working
pressure applied shall be used.
3.18 A minimum factor of safety of 4 for working
pressure applied shall be used.
Section 3.0 General Requirements
3.1
All piping shall be run parallel to building walls.
3.2
Grouped piping shall be supported on racks
either on horizontal or vertical planes.
3.19 For conveying liquids subject to water hammer,
additional safety factor of a minimum of 100% of
working pressure shall be used.
212
CHAPTER 11
-
PIPING
3.20 Piping supports shall be placed on a 3 000 mm
intervals or less.
Water
3.21 All piping carrying steam, hot water or hot liquids
shall be insulated to prevent accidental contact
and loss of heat.
Steam
3.22 Drains for steam piping shall be provided with
steam traps.
3.23 On all screwed joints the threaded portion shall
enter fittings with three threads by hand before a
pipe wrench is applied.
Green
Gases in either gaseous or liquified form,
vapour and pneumatically conveyed fumes
and materials
3.24 Pipe threads shall be lubricated by white lead,
red lead graphite and oil or other approved
thread lubricants before tightening.
Acid and alkalis
3.25 No rubber or rubberized gaskets shall be used
for steam or hot liquids.
Air
3.26 A shut off valve shall be installed to every
branch from headers.
Sifeer-Gray
Oil-mineral vegetable or
animal, Flammable or
Combustible
I
I
I
Yellow Ochre
Other fluids, including drainage
pipes unless the drain is to a
particular service
3.27 All piping shall be reasonably cleaned before
installation.
Fire fighting materials, including
detection and suppression
system
3.28 All piping shall be free from burrs or protruding
metals inside.
Safety Red
Hazardous services (generally
with other identification of contents)
3.29 No piping carrying steam or hot liquids shall be
imbedded in concrete walls or floors.
Safety Yellow
Electricity
3.30 Where piping has to be located in trenches the
pipes shall be supported on steel benches on
floor of trench.
3.31
I
I
I
Brown
1
Light Orange
Communications
Where piping has to be located in trenches a
suitable drainage or sump for removal of liquid
accumulations shall be provided for trench.
‘Mite
In addition to color coding, the specific contents of
piping must be identified by sticker, stencil, tag, etc.
3.32 Where piping carrying steam or hot liquids have
to pass walls of concrete suitable sleeves made
of pipes one size bigger shall be imbedded in
concrete before piping is laid.
4.2 Color bands and pipe flow identifications shall be
as specified and installed as shown in page 192.
3.33 Piping to all equipments shall not impose any
stress on equipment being connected.
Section 5.0 Fluid Flow Velocities
5.1
3.34 Pipe carrying liquids with solids shall use long
radius elbows or tees with plugs in the direction
of flow.
Section 4.0 Identification Colors for Pipes
4.1 Identification of piping by color, or color bands at
convenient locations shall be as follows:
213
In practice, the average fluid flow velocities may
be as follows:
a.
Water
b.
High Pressure Saturated
Steam
25— 50 meters/sec.
1.5—3.0 meters/sec.
CHAPTER 11
c.
High Pressure Superheated
Steam
50 77 meters/sec.
Atmospheric Exhaust
Steam
40 60 meters/sec.
Material
Bolting
Staybolt wrought-iron, solid
Hot-rolled carbon-steel bars
Alloy-steelbolting materials for
high temperature
Carbon and Alloy steel nuts for
bolts for high-pressure and high
temperature service
—
e.
Low Pressure Exhaust
Steam
100— 120 meters/sec.
Note: See appendices for Steel Pipes, uPVC
Pipes and uPVC Electrical Conduits.
Section 6.0 Power Piping Systems and
Design
6.1
6.2
6.3
PIPING
Table 11.6.2 List of Material
Specifications for Bolting, Fittings, Valves and
Flange, Pipe and Tubing
—
d.
-
Heat-treated carbon-steel bolting
material
Steel machine bolts, nuts and tap
bolts
Scope. Power piping systems include all steam,
water and oil piping and the component parts
such as the pipe, flanges, bolting, gaskets,
valves, and fittings for steam generating plants,
central heating plants and industrial plants.
Specification
ASTM A-84
ASTM A-i 07
ASTM A-i 93
ASTM A-i94
ASTM A-261
ASTM A-307
(Grade B)
Fi ttings, Valves and Flanges
‘Composition brass or ounce metal
casting
Steam or Valve bronze castins
Gray iron casting for valves,
1
flanaes and oioe fittins
Cast iron for bell and spigot fittings
1
and valves
Cast iron fittings, short body, 3 in,
1
(80mm) to 12 in. (300mm) for 250
psi (i724 kPa) water pressure plus
water hammer
Materials. Materials used shall conform to Table
11 .6.2.any materials other than those specified
meet the
should
physical
& chemical
requirements & test of the latest revision of the
respective specifications in Table 11.6.2.
Valves. It is mandatory that valves be (a) of the
design or equal to the design which the
manufacturer thereof recommends for the
service, and (b) of materials allowed by the code
for the pressure & temperature.
All valves in nominal sizes:
80mm and smaller for pressures above 1724
kPa but not above 2758 kPa.
50mm smaller for pressures above 2578 kPa
not above 4137 kPa.
40mm and smaller for pressures above 4137
kPa may have screwed, flanged, or welding
ends.
For all valves, larger than sizes specified in the
preceding paragraph, flanged or welding ends
shall be used.
Insert Pipe Flow Identification p.192 (PSME)
214
ASTM B-62
ASTM B-61
ASTM A-126
AWWA C 100
ASA A21 .10
Cuoola malleable iron
Carbon steel castings for valves,
flanges and fittings for hightemperature service
ASTM A-i97
ASTM A-95
Carbon Steel casting suitable for
fusion weldingfor high
temoerature service
Alloy-steel casting suitable for
fusion welding for high
temperature service
Forged or rolled steel pipe
flanges, forged fittings, and
valves and parts for high
temperature service
Forged or rolled steel pipe
flanges for general service
Forged or rolled alloy-steel pipe
flanges, forged fittings and
valves and parts for high
temperature service
Factory-made wrought carbonsteel and carbon molybdenumsteel welding fittings
ASTM A-216
ASTM A-217
ASTM A-i 05
ASTM A-i81
ASTM A-i82
ASTM A-234
CHAPTER 11
Ferritic and austentic steel
casting for high temperature
service
Pipe
Non-Ferrous
Copper pipe, standard sizes
2
Red Brass pipe, standard sizes
2
Cast-Iron
Pipe, water, cast-iron (Bell and
spigot) Cast-iron, pit-cast pipe
for water or other liquids
Cast-iron, centrifugally cast in
1
metal molds for water or other
liquids
Cast-iron, centrifugally cast in
sand-lined molds for water or
other liquids
Steel and Wrought Iron
Welded wrought iron-pipe
Welded and seamless steel
pipe
Forged or rolled steel pipe
flanges, forged fittings, and
valves and parts for high
temperature service
Seamless carbon-steel pipe for
high temperature service
Black and hot-dipped zinc
coated (galvanized) welded and
seamless steel pipe for ordinary
uses
Electric-fusion-welded steel pipe
(750 mm and over)
Electric-resistance-welded steel
pipe
Electric-fusion-welded steel pipe
(100 mm to 750 mm)
Electric-fusion-welded steel pipe
for high-temperature and high
pressure service
Seamless ferritic alloy-steel pipe
for high temperature service
Seamless and welded austenitic
stainless steel pipe
Ferritic alloy steel forged and
bared pipe for high-temperature
Seamless austenitic steel pipe
for high-temperature central
station service
Spiral-welded steel or iron pipe
jLine pipe
Tubing
Non-Ferrous
Seamless copper tubing, bright
-
PIPING
ASTM A-351
annealed
Seamless copper tubes
Copper and copper-alloyseamless (Condenser tubes)
Steel
Seamless steel boiler tubes
Electric-resistance-welded steel
and open-heart iron boiler tube
Seamless steel boiler tubes for
high-pressure service
Medium-carbon seamless steel
boiler and superheater tubes
Seamless alloy-steel boiler and
superheater tubes
Seamless cold-drawn lowcarbon steel heat-exchanger
and condenser tubes
Electric-resistance-welded steel
heat exchanger and condenser
tubes
Electric-resistance-welded steel
boiler and superheater tubes for
high-pressure
Welded alloy-steel boiler and
superheater tubes
Copper brazed steel tubing
ASTM B-42
ASTM B-43
FSB WW P-421
ASA A21 .2
ASA A21 .6
ASA A21 .6
ASTM A—53
ASTM A-72
ASTM B-75
ASTM B -111
ASTM A-83
ASTM A -178
ASTM A-i 92
ASTM A-2i0
ASTM A-2i3
ASTM A-179
ASTM A-214
ASTM A-226
ASTM A-249
ASTM A-254
ASTM A-53
Cast iron shall not be used over 232.2°C (450°F)
1
and not for oil over 145°C (293°F).
Copper or brass shall not be used over 207.7°C
2
406° F).
Mallelable iron or bronze shall not be used over
260°C (500°F).
ASTM A-105
ASTM A -106
6.4
ASTM A-i 20
Wall Thickness. The following formula shall be
used to determine pipe wall thickness:
ASTM A-134
tm
ASTM A -135
PD
÷C
2S + ‘(P
Where:
tm = minimum pipe wall thickness in mm
P maximum internal service pressure in kPa
t = nominal pipe wall thickness in mm
D = outside diameter of pipe in mm
S = allowable stress in materials in kPa
C = allowance for threading, mechanical
strength or corrosion in mm, see Table
ii.6.4a
Y co-efficient for values, see Table 11 .6.4b
ASTM A-i39
ASTM A-155
ASTM A-335
ASTM A -312
ASTM A-369
*Since all pipe furnished by the mill is subject
to 12 1/2 % variation in wall thickness, the
thickness tm should be multiplied by 8/7 to
obtain the nominal wall thickness.
ASTM A-376
ASTM B-68
215
CHAPTER 11
-
PIPING
FLOW INDICATING ARROW
SAME COLOR AS BANDS
TYPYCAL PIPE-COLOR BANDING-INSULATED
NOTE:
BANDSMAY BE PAINTED AS PER COLORCODE OR 38mm PLASTIC
PRESSURE-SENSETIVE TAPE USED (LAPPLASTIC AT LEAST 50 mm
AT JOINT)
4
300mm
38mmL
FLOW DIAGRAM ARROW FOR
PIPES UNDER 150mm & INCLUDING
INSOLATION IS FUSED
FLOW DIAGRAM ARROW FOR
PIPES 150MM & OVER INCLUDING
INSOLATION IF FUSED.
NOTES
1.
2.
3.
4.
ARROWS
ARROWS
ARROWS
ARROWS
SHALL BE
SHALL BE
SHALL BE
SHALL BE
STENCIL TYPE
SAME COLOR AS PIPE BANDING
READABLE FROM FLOOR
INSTALLED EVERY 456
PIPE FLOW IDENTIFICATION
NOTES
ALL ARROWS SHALL BE PAINTED ON PIPES
STICK-ON OR GLUED-ON ARROWS WILL NOT BE ACCEPT TABLE
216
CHAPTER 11
-
PIPING
Table 11.6.4a
equipment on the low pressure side does
not meet the requirements for the full initial
pressure. The relief or safety valve shall be
located adjoining or as close as possible to
the reducing valve. Proper protection shall
be provided to prevent injury or damage
caused by escaping fluid from relief or
safety valves if vented to the atmosphere.
The vents shall be of ample size and as
short and direct as possible. The combined
discharge capacity of the relief valves shall
be such that the pressure rating of the lower
pressure piping and equipment will not be
exceeded if the reducing valves sticks open.
Value of C in inches
(mm)
Type of Pipe
Cast-iron Pipe, Centrifugally
cast
Cast-iron Pipe, Pit-Cast
Threaded Steel, Wroughtiron or Non-Ferrous Pipe
(10mm ) 3/8 in. add smaller
(15 mm) 1/2 in. and larger
Grooved Steel, Wrought-iron
or Non-ferrous Pipe
Plain-end Steel or Wrought
iron
Pipe or tube for 1 in (25 mm)
Size and smaller
Pipe or tube for sizes above
(25.4 mm) 1 in.
Plain-end Non-ferrous pipe
or tube
0.14 (3,556 mm)
0.18 (4.527 mm)
0.05 (1.27 mm)
Depth of Thread in mm
Depth of Groove in mm
b.
0.05 (1.27 mm)
0.065 (1.651 mm)
6.7
Pipe
0.000
a.
Table 11.6.4 (b)
“Y” Values
Type of Steel 900°F and 950
below
1000 1050 1110 1150& above
Ferritic
Austentic
0.4
0.4
0.7
0.4
NOTE: °C
°F
6.5
6.6
0.5
0.4
It is mandatory that a pressure gage be
installed on the low pressure side of a
reducing valve.
0.7
0.4
0.7
0.5
0.7
0.7
32
1.8
For pressure above 4 137 kPa, the pipe
shall be:
1.
Seamless steel meeting ASTM
specifica-tions A-106, A-312, A-335
or A-376; or
2.
Forged and bored steel meeting A369 or
3.
Automatic welded steel meeting A312 or
4.
Electric-fusion welded steel pipe
meeting with ASTM specifications
A-155.
—
Variations in Pressure and Temperature.
Either pressure or temperature, or both, may
exceed the nominal design values if the
computed stress in the pipe wall calculated for
the pressure does not exceed the allowable S
value in Table 11.6.5 and 11.6.5a for the
expected temperature by more than the
following allowances for the period of duration
indicated:
a.
Up to 15 percent increase above the S value
during 10 percent of the operating period.
b.
Up to 20 percent increase above the S value
during one percent of the operating period.
b.
For pressure above 1 724 kPa, but not
above 4 137 kPa, pipe shall be:
1.
Electric-fusion welded steel of
ASTM specification A-134 or A-139
2.
Electric-resistance welded
steel
pipe of ASTM specification A-i 35
3.
Forged or bored steel meeting A380; or
4.
Automatic welded steel meeting
A-312.
5.
Electric-Fusion welded steel pipe
meeting with ASTM specifications
A-155.
Pressure Reducing and Relief Valves
a.
Where pressure reducing valves are used,
one or more relief or safety valves shall be
provided on the low pressure side or the
reducing valve in case the piping or
217
______I_
CHAPTER 11
-
PIPING
Table 11.6.5
Allowable Stresses for Pipe in Power Piping Systems
ASTM
Specification
Material
Welded Material:
Furnace Welded
Carbon Steel
Lap Welded
Butt Welded
Grade
Minimum
Ultimate
Tensile
Strength
Values S psi for Temperatures in Deg Not to Exceed
-20 to
100
200
300
400*
450
8,800
6,500
8,600
6,350
8,200
6,100
7,800
5,850
7,600
5,700
15,950
15,950
14,450
13,450
10,800
10,600
10,200
9,800
60,000
15,000
15,000
15,000
15,000
75,000
18,750
18,750
17,000
15,800
B 43
8,000
8,000
7,000
3,000
B 42
6,000
5,500
4,750
3,000
B 42
6,000
5,500
4,750
3,000
30,000
30,000
6,000
6,000
6,000
5,500
5,500
5,500
4,750
4,750
4,750
3.000
3,000
3,000
42,000
42,000
6,000
3,600
5,500
3,300
4,750
2,850
3,000
1,800
6,000
6,000
6,000
6,000
6,000
6,000
6,000
6,000
6,000
6,000
4,000
4,000
4,000
4,000
4,000
A 120
A 120
500
600
650
12,9000
12,650
12,600
14,500
14,000
13,700
15,200
14,900
14,850
Automatically Welded
Sustenitic Stainless
Steel
18% chromium,
8% Ni—Ti
18%chromium,
8%Ni.—Cb
-
-
-
18% chromium,
8% Ni. Cb.
TP321
A312
TP347
75,000
Seamless Material
Carbon steel
5%chromium,
%Mo.
2
/
1
18% chromium,
8% Ni. Ti
A312
-
-
Seamless
Red brass
Copper
2 in.& smaller
Copper
over 2 in.
A 120
A 335
A335
A 369
A 312
A 376
A213
A 312
A 376
A 213
P5
P5b
FP5
TP321
9,600
TP347
—
—
Copper tubing
Annealed
Bright annealed
B 75
B 88
B 68
Copper Brazed Steel
A 254
Class I
Class II
FSB
WWP-421
ASA A 21.6
ASA B 21.8
ASAA21.2
Types
I & II
Cast iron3
Centrifugally
Cast
Metal Molds
Sand-lined Molds
Pit cast
ipe in accordance with API Specification.
1
P
in excess of the maximum temperatures for
he several types and grades of pipe tabulated above shall not be used at temperature
2
T
.) Allowable S values for
contemplated
conditions
service
which the S values are indicated. (See also specific requirements for
.
interpolation
by
obtained
be
may
intermediate temperatures
for oil having a temperature above 300 F.
ast-iron pipe shall not be used for lubricating oil lines for machinery and in any case not
3
C
*For steam at 250 psi (405 F) the values given may be used.
Note: Multiply S in psi by 6.895 to get S in kPa or Divide S in psi by 0.145 to get S in kPa.
*0
=
*F —32
1.8
218
CHAPTER 11
-
PIPING
Table 11.6.5
Allowable Stresses for Pipe in Power Piping Systems
Note: Where welded construction is used, consideration should be given to the possibility of graphite formation in the
following
steels: Carbon steel above 775 F; Carbon-mdybdenum steel above 875 F; Chrome molybdenum steel (with chromium
under 060)
above 975 F.
Material
Welded Material:
Furnace Welded
Lap Welded
carbon Steel
Wrought Iron
Butt Welded
Carbon Steel
Wrought Iron
Electricfusion welded:
Carbon Steel
Minimum
Ultimate
Tensile
Strength
11650
A 53
A 72
45,000
40,000
9,000
8,000
A 53
45,000
40,000
6,70
6,000
ASTM
Specification
A 134
Grade
Identi
Fication
Symbol
Values S psi for Temperatures in Dog Not to Exceed
70
750
800
850
7,500
8,450
9,200
5,950
6,550
7,000
10,850 9,200
11,650 9,700
12,450 10,250
13,250 10,800
7,000
7,000
7,000
7,000
900
A 245 A
A 245 B
A 245 C
A 283 A
A 283 B
A 283 C
A 2830
A4
B4
C45
c50
C55
48,000
52,000
55,000
45,000
50,000
55,000
60,000
48,000
60,000
45,000
50,000
55,000
8,800
9,600
10,100
8,300
9,200
10,100
10,100
9,600 9,250
8,300
12,000 11,350 9,950
10,100 9,800 8,700
11,250 10,900 9,900
12,400 11,900 10,850
Killed Carbon Steel
KC55
KC6O
KC65
KC7O
55,000
60,000
65,000
70,000
12,400
13,500
14,600
15,750
Csrbon Molybdemun Steel
CM65
CM7O
CM75
65,000
70,000
75,000
14,600 14,600 14,600 14,100 12,950 11,250
15,750 15,750 15,750 15,200 13,500 11,450
16,850 16,850 16,850 16,200 14,300 11,700
1/2% chrom., 1/2% moly steel
1% chrom., 14% moly steel
1 14% chrom., 14% rnoly steel
2 14% chrom., 1% moly steel
1/2CR
1CR
11/4CR
2 1/4CR
65,000
60,000
60,000
60,000
14,600
13,500
13,500
13,500
14,600
13,500
13,500
13,500
A
3
3
B
A°
3
B
48,000
60,000
48,000
60,000
10.200
12,750
10,200
12,750
10,200 9.100
12,750 11,000
10,200 9,100
12,750 11,000
A 312
TP321
TP347
75.000
Note6
12,550
A 53
A 53
A
B
48,000
60,000
12,000 11,650 10,700 9,000
15,000 14,350 12,950 10,800
7,100
7,800
5,000
5,000
A 106
A106
A
B
48,000
60,000
12,000 11,650
15,000 14,350
10700
12950
9,000
10,800
7,100
7,800
5,000
5,000
A 83
A 179
A 192
A 210
Type A
Low carb.
47,000
11,750 11,450
10550
9,000
7,100
5,000
15,000 14,350
12950
10,800
7,800
5,000
A 139
A 155
Electric Resistance
Welded:
Carbon Steel
A 53
A 135
Automatically Welded
Stainless Steel:
18% Cr-8% Ni-Ti
18% Cr-8% Ni-Cb
Seamless Msterial
Carbon Steel
47,000
60,000
11,900
12,900
13,950
14,950
14,600
13,500
13,500
13,500
14,100
13,250
13,500
13,500
12,950
12,750
12,950
12,950
11,250
11.800
11,800
11,800
950
9,000
9,000
9,000
9,000
1,000
5.600
6.750
7,000
7,000
1050
4.500
4,950
5,200
219
12,550 12,350 12,150 12,000 11,750 11,500 11,150
1,100
1,150
2.500
3,600
3,750
2,700
750
6,450
1,200
4,250
0
75,000
Note 6
Note 6
14,800
14,800
13,400
14,700
14700
13,100
14,550
14,550
12,800
14,300
14,300
12,400
14,100
14,100
10,900
13,850
13,850
9,000
13,500
13,500
5500
13,100
13,100
3,500
10,300
10,300
2,500
7,600
7.600
—32
1.8
Pipe in accordance with API Specification.
1
be
temperatures for which the S values indicated. Allowable S values for intermediate temperatures may
he several types and grades of pipe tabulated above shall not be used at temperatures in excess of the maximum
2
T
obtained by interpolation.
may be increased by the ratio of 095 divided by 090
The values tabulated are for class 2 pipe. For Class 1 pipe which is heat treated and radiographed, thee stresses
3
times the
manufacture of ordinary electric fusion welded steel pipe, the allowable Stress shall be taken as 0.20
1f plate material having physical properties other than stated in the SATM Specification A 139 is used in the
4
below.
and
450F
of
tensile strength for temperature
the
under this classification is subjected of supplemental test and/or heat treatments as agreed to by
For electroresistance-welded pipe for applications where the temperature is below 650F and where pipe furnished
5
pipe the S values equal to
the strength characteristics of the weld to be equal to the minimum tensile strength specified for the
supplier and the purchaser, whereby such supplemental test and/or heat treatments demonstrate
the corresponding seamless grades may be used.
TP347
A213
A 312
18%Cr—8%Ni-Cb
-
TP321
A 213
A 312
A_376
Stainless steel
18% Cr— 8% Ni-Ti
75,000
Note 6
60000
1,800
2,200
3,300
5,200
7,300
10,000
11,500
12,400
12,800
13,100
13,400
Note 6
60,000
P5
FP5
P5b
A 335
A369
A 335
-
1/2% Mo
5% Cr
2,700
4,000
5,500
7.000
9,000
12,000
13,200
3,000
13,900
4,200
14,500
5,800
14,800
7800
15,000
11,000
60,000
13,100
T21
P21
FP21
14,400
A213
A 335
A369
15,000
3%Cr-%%Mo
15,000
60000
T22
P22
FP22
A213
A 335
A369
‘fl/4%Cr-1%Mo
15,000
4,000
5,500
7,800
11,000
13,100
14,400
15,000
15,000
15,000
15,000
60,000
P11
FPII
A 335
A369
1 %% Cr-112% Mo
15,000
2,800
5,000
7,500
11,000
13,100
14,200
14,750
15,000
15,000
15,000
60,000
P12
FP12
-
1,150
A 335
A369
1,100
1% Cr-1/2% Mo
1,050
6,250
1,000
10,000
12,250
950
12,500
13,150
900
13,150
13,450
850
13,450
13,750
800
13,750
13,750
750
13,750
13,750
700
13,750
55,000
20 to 1650
Values of s Psi for Temperatures in Dea Not to Exceed
55,000
P1
FPI
Tensile
Strength
Minimum
P2
FP2
A 335
A369
Grade
Identi-
A 335
A 369
Chronr. Molybnum
‘,4% Cr-1/2% Mo
Carbon molybrium
Material
ASTM
Specifi-
formation in the following steels:
Note: Where welded construction is used, consideration should be given to the possibility of graphite
under 0.60) above 975 F.
Carbon steel above 775 F; carbon-molybdenum steel above 875 °F; Chrome-molybdenum steel (with chromium
Table 11.6.5a
Allowable Stresses for Pipe in Power Piping System (Continued)
5,000
5,000
1,500
1,200
z
-
m
-1
C)
I
CHAPTER 11
-
PIPING
Table 11.6.5c Properties of Pipe (Continued)
NOM.
PIPE
SIZE
(in)
1/8
1/4
3/8
1/2
3/4
1
1 1/4
1 1/2
2
2 1/2
3
3 1/3
4
5
6
8
10
12
14
16
18
20
24
SCHEDULE
NO. +
40 (S)
80(X)
40(S)
80(X)
40(5)
80(X)
40(S)
80 (X)
40(5)
80(X)
40(5)
80(X)
40 (5)
80 (X)
40(S)
80 (X)
40 (5)
80 (X)
40 (S)
80 (X)
40 (5)
80 (X)
40(5)
80 (X)
40 (5)
80 (X)
40 (5)
80 (X)
40 (S)
80 (X)
40 (S)
80 (X)
40 (S)
60 (X)
80
30 (S)
40
(X)
80
30 (5)
40
(X)
80
30 (5)
40 (X)
80
(S)
(X)
40
80
20 (S)
20 (5)
40
80
20 (S)
(X)
40
80
OUTSIDE
DIAM
(in)
.405
.405
540
540
.675
.675
.840
.840
1.050
1.050
1.315
1.315
1.660
1.660
1.900
1.900
2.375
2.375
2.875
2.875
3.500
3.500
4.000
4.00
4.500
4.500
5.563
5.563
6.625
6.625
8.625
8.625
10.750
10.750
10.750
12.750
12.750
12.750
12.750
14.000
14.000
14.000
14.000
14.000
16.000
16.000
16.000
16.000
18.000
18.000
20.000
20.000
20.000
20.000
24.000
24.000
24.000
24.000
INSIDE
DIAM
(in)
.269
.215
364
302
.493
.423
.622
.546
.824
.742
1.049
.857
1.380
1.278
1.610
1.500
2.067
1.939
2.469
2.323
3.068
2.900
3.548
3.364
4.026
3.826
5.047
4.813
6.065
5.761
7.981
7.625
10.020
9.750
9.564
12.090
11.938
11.750
11.376
13.250
13.125
13.000
12.500
15.250
15.000
14.314
17.250
17.000
16.874
16.126
19.250
19.000
18.814
17.938
23.250
23.000
22.626
21.584
WALL
THICKNESS
(in)
.068
.095
.088
.119
.091
.126
.109
.147
.113
.154
.133
.179
.140
.191
.145
.200
.154
.218
.203
.276
.216
.300
.226
.318
.237
.337
.258
.375
.280
.432
.322
.500
.365
.500
.593
.330
.406
.500
.687
.375
.438
.500
.750
.375
.500
.843
.375
.500
.562
.937
.375
.500
.593
1.031
.375
.500
.687
1218.00
WEIGHT
OF PIPE
(Ib/ft)
.244
.314
.424
.535
.567
.738
.850
1.087
1.130
1.473
1.678
2.171
2.272
2.996
2.717
3.631
3.652
5.022
5.79
7.66
7.57
10.25
9.11
12.51
10.79
14.98
14.62
20.78
18.97
28.57
28.55
43.39
40.46
54.70
64.33
43.80
53.53
65.40
88.51
54.60
63.37
72.10
106.31
62.40
82.77
136.46
70.60
93.50
104.75
170.75
78.60
104.20
122.91
208.87
94.60
125.50
171.17
293.36
*To change Wt of Water in Pipe (lb/fl) to kg/meter of water,
multi. by 1.488
*To change sq ft/ft to sq m/meter, multiply by 0.305
t S is designation of standard wall pipe
X is designation of extra strong wall pipe
221
WTOF
WATER
IN PIPE*
(lb/fl)
.0246
.0157
.0451
.0310
.0827
.0609
.1316
.1013
.2301
.1875
.3740
.3112
.6471
.5553
.8820
.7648
1.452
1.279
2.072
1.834
3.20
2.86
4.28
3.85
5.51
4.98
8.66
7.87
12.51
11.29
21.6
19.8
34.1
32.4
31.1
49.6
48.5
46.9
44.0
59.8
58.5
55.8
51.2
79.1
76.5
69.7
100.8
98.3
97.2
88.5
126.7
122.5
120.4
109.4
184.6
179.0
174.2
158.2
OUTSIDE
SURFACE
(sq ft/if)
.106
.106
.141
.141
.177
.177
.220
.220
.275
.275
.344
.344
.434
.434
.497
.497
.622
.622
.753
.753
.916
.916
1.047
1.047
1.178
1.178
1.456
1.456
1.735
1.735
2.26
2.26
2.81
2.81
2.81
3.34
3.34
3.34
3.34
3.67
3.67
3.67
3.67
4.18
4.18
4.18
4.71
4.71
4.71
4.71
5.24
5.24
5.24
5.24
6.28
6.28
6.28
6.28
INSIDE
SURFACE
(sq ft/if)
.0705
.0563
.0955
.0794
.1295
.1106
.1637
.1433
.2168
.1948
.2740
.2520
.3620
.3356
.4213
.3927
.5401
.5074
.6462
.6095
.802
.761
.926
.880
1.055
1.002
1.321
1.260
1.587
1.510
2.090
2.006
2.62
2.55
2.50
3.17
3.13
3.08
2.98
3.46
3.44
3.40
3.27
3.99
3.93
3.75
3.52
3.45
4.42
4.22
5.04
4.97
4.93
4.70
6.08
6.03
5.92
5.65
TRANS
VERSE
AREA
(sq in)
.0568
.0364
.1041
.0716
.1910
.1405
.3040
.2340
.5330
.4330
.8640
.7190
1.495
1.283
2.036
1.767
3.355
2.953
4.788
4.238
7.393
6.605
9.89
8.89
12.73
11.50
20.01
18.19
28.99
26.07
50.0
45.6
78.9
74.7
71.8
115.0
111.9
108.0
101.6
138.0
135.3
133.0
122.7
183.0
176.7
160.9
234.0
227.0
224.0
204.2
291.0
284.0
278.0
252.7
426.0
415.0
402.1
365.2
CHAPTER 11
b.
c.
6.8
1.
Seamless steel in accordance with
ASTM specification A-106.
2.
Electric-fusion welded steel pipe of
ASTM specification A-i 55.
3.
steel
Electric-resistance welded
pipe of ASTM specification A-135 or
4.
electric-resistance
or
Seamless
of ASTM
pipe
steel
welded
A-53
of
specification
For
A-193.
specifications
only
400°C,
exceeding
temperature
bolts studes are recommended.
When cast iron flanges are used,
bolting material shall be of carbon
ASTM
to
conforming
steel
specification A-307, Grade B, or A107, Grade 1120.
For service up to 400°C and pressure of not
over 1724 kPa, any of the following classes
of pipe may be used:
Electric-fusion welded steel of
ASTM specification A-i 34 or A-i 39.
2.
steel
Electric-resistance welded
pipe of ASTM specification A-i 35 or
3.
pipe
Wrought-iron
specification A-72.
of
6.9
b.
Flange bolts or bolt-studs shall be of the
dimensions and material specified for the
purpose in the corresponding American
flange standards. Bolts or bolt-studs shall
extend completely through the nuts and if
desired, may have reduced shank of a
diameter not less than the diameter at root
of threads.
c.
Nuts shall conform to ASTM specification A194.
Flanges
a.
Flanges shall conform to the American
Standard B 16.5 for respective pressures
and temperature or to the specifications set
by the manufacturer.
b.
172 kPa and class 862 kPa cast-iron
integral or screwed companion flanges may
be used with a full face gasket or with a ring
gasket extending to the inner edge of the
bolt holes. When using a full face gasket,
the bolting maybe of heat-treated carbon
steel (ASTM-A26i), or alloy steel (ASTM A193). When using a ring gasket, the bolting
shall be of carbon steel equivalent to ASTM
A-307, Grade B, without heat-treatment
other than stress relief.
c.
When bolting together two Class 1724 kPa
integral or screwed companions cast-iron
flanges, having 1 .6 mm raised faces, the
bolting shall be of carbon steel equivalent to
ASTM A-307, Grade B. Without heattreatment other than the stress relief.
d.
1034 kPa steel flanges may be bolted to
cast-iron valves, fittings or other parts,
having either integral Class 862 kPa castiron flanges or screwed Class 862 kPa
companion flanges. When such construction
is used, the 1.6 mm raised face on the steel
flange shall be removed. When bolting such
flanges together using a ring gasket
extending to the inner edge of the bolt holes,
the bolting shall be of carbon steel
ASTM
d.
Grade A seamless steel pipe of ASTM
specification A-106, wrought-iron pipe of
ASTM A-72, Grade A seamless steel pipe of
ASTM A-53, or grade A electric welded pipe
of ASTM A-53, A-135 or A-139 shall be
used for close coiling, cold bending or other
uses.
e.
Pipe permissible for the service specified in
Sec. 11.6.7.3 may be used for temperature
higher than 400°C unless otherwise
prohibited, if the S value in accordance with
Sec. 11.6.4 is used when calculating the
pipe wall thickness.
Pipe meeting API Specification 5L may also
be used.
Boltings
a.
PIPING
For pressure above 1724 kPa, but not
above 4137 kPa, pipe shall be:
1.
f.
-
The following
bolting:
1.
standards
shall
apply to
For steam service pressure in
excess of 1724 kPa or for steam or
temperature
service
water
bolting
the
232°C,
exceeding
material shall conform to ASTM
222
CHAPTER 11
-
PIPING
equivalent to ASTM A-307 Grade B, without
heat-treatment othen than stress relief.
When bolting such flanges together using
full face gasket, the bolting may be heat
treated carbon steel (ASTM A-261) or alloy
steel (ASTM A-193).
e.
a.
2069 kPa steel flanges may be bolted to
cast-iron valves, fittings, or other parts
having either integral Class 1724 kPa castiron flanges or screwed Class 1724 kPa
Cast-iron companion flanges without any
changes in the raised faces on either flange.
Where such construction is used, the bolting
shall be of carbon steel equivalent to ASTM
A-307 Grade B, without heat treatment other
than stress relief.
-
b.
6.10 Fittings
a.
b.
6.11
The minimum meal thickness of all flange or
screwed fittings and the strength of factorymade welding fittings shall not be less than
that specified for the pressure and
temperatures in the respective American
Standards.
a.
All fittings in nominal sizes above; 80 mm for
pressures above 1724 kPa but not above
2758 kPa; 50 mm for pressures above 2758
kPa but not above 4137 kPa, and 40 mm for
pressures above 4137 kPa but not above
17238 kPa shall have flanged ends or
welding ends.
Gaskets where required, shall be of material
that resists attack by the fluid carried in the
pipe line, shall be strong enough to hold the
pressure, and perform the purpose intended
throughout
the
temperature
range
encountered. Gaskets shall be as thin as the
finish of the surface that will permit to
reduce possibility of blowing out.
b.
Paper, vegetable fiber, rubber or rubber
inserted gaskets shall not be used for
temperatures in excess of 121°C.
c.
Asbestos composition gaskets may be used
as permitted in the American Standard for
steel pipe flanges and flange fittings. This
type of gaskets shall not be used on lines
carrying oil or other
Hangers and supports shall permit free
expansion and contraction of the piping
between anchors. All piping shall be carried
on adjustable hangers properly leveled
supports, and suitable springs, sway
bracing, vibration dampeners, etc. shall be
provided where necessary.
6.13 Pipe Sleeves
Gaskets
a.
Piping and equipment shall be supported in
a thoroughly substantial and workman like
manner, rigid enough to prevent excessive
vibration and anchored sufficiently to
prevent undue strains on boilers and the
equipment served. Hangers, supports, and
anchors shall be made of durable materials.
In tunnels and buildings of permanent fire
proof construction, piping may be supported
on or hung from wood structures if all piping
used for conveying fluid at temperatures
above 121°C us spaced or insulated from
such
wooden
members
to
prevent
dangerous heating.
Where steam pipe pass through walls,
partitions, floors, beams, etc., constructed of
combustible material, protecting metal
sleeves or thimbles shall be provided to give
a clearance of not less than 6.35 mm under
hot and cold conditions all around the pipe,
or pipe and covering. When steam pipes
pass through metal partitions, etc., a
clearance of at least 6.35 mm under hot and
cold conditions shall be left all around the
pipe, or pipe covering. In any cases, if the
fluid temperature exceeds 121°C, the pipe
shall be insulated inside the sleeve with a
covering of at least standard thickness.
Walls, floors, partitions, beams, etc., shall
not be cast solidly to or built up around and
in contact with a steam, hot water, or hot oil
pipe. Where such pipe must be installed in a
concrete floor or other building member, it
shall be protected for the entire buried
length with a suitable protecting pipes
sleeve of steel, cast iron, wrought iron, or
tile; exception maybe taken to the preceding
rules where pipes pass through walls, floors,
partitions, etc., that must be kept water tight.
6.14 Drains, Drips, and Steam Traps
a.
6.12 Hangers, Supports, Anchors
223
Suitable drains or drips shall be provided
wherever necessary to drain the condensate
from all sections of the piping and
CHAPTER 11
-
PIPING
If a hydrostatic mill test pressure for pipe is
not stated in any of the specifications
enumerated in Table 11.6.2, the pipe shall
be capable of meeting a minimum internal
hydrostatic test pressure determined from
the formula.
equipment whenever it may collect. Suitable
drains shall also be provided to empty water
lines, water storage tanks, equipment
containing water, etc., when such piping and
equipment is out of service. At least one
valve shall be placed in each drip or drain
line.
b.
P
Drip lines from steam headers, mains,
separators, and other equipment shall be
properly drained by traps installed in
accessible locations and below the level of
the apparatus drained. Drip pumps, drip
(preferably with orifice control) maybe used
in lieu of traps, if they are safely installed,
protected and operated under regular
supervision. All drain lines shall have drip
valves for free blow to the atmosphere.
c.
Drip lines from steam headers, mains,
separators, and other equipment operating
at different pressures shall not be connected
to discharge through the same trap. Where
several traps discharge into one header
which is or maybe under pressure, a stop
valve and a check valve shall be placed in
the discharge line from each trap.
d.
Trap discharge piping shall have the same
thickness as the inlet piping unless it is
vented to atmosphere or operated under low
pressure and has no stop valves. The trap
have at least the
discharge piping shall
pressure rating of the maximum discharge
pressure to which it maybe subjected
against freezing where necessary. Drainage
from steam traps, if open to atmosphere,
shall be safeguarded to prevent accidents
from hot discharge.
Where:
P
b.
6.15 Hydrostatic Tests
a.
2St
D
Before Erection. All valves, fittings, etc.,
shall be capable of withstanding a
hydrostatic shell test made before erection
equal to twice the primary steam service
pressure, except that steel fittings and
valves shall be capable of withstanding the
test pressure as given in the American
Standard for Steel Pipe Flanges and
Flanged Fittings for the specific material,
pressure standard and facing involved (ring
joint facing for welding ends.) Pipe shall be
capable of meeting the hydrostatic test
requirements contained in the respective
specifications in Table 11.6.2, under which it
is purchased.
=
test pressure in kPa
t
nominal pipe wall thickness in
mm.
D
pipe outside diameter in mm,
and
S
allowable stress in material in
Kilopascal and which shall be
taken as not less than 50
percent of the specified yield
pint of the material except that
hydrostatic tests shall not
exceed 17 238 kPa for sizes
80 mm and below, or 19 306
kPa for size over 80 mm nor
shall the stress produced
exceed 80 percent of the
specified yield point.
After Erection. All piping systems shall be
capable of withstanding a hydrostatic test
pressure of one and one-half times the
design pressure, except that the test
pressure shall in no case exceed the
adusted pressure-tern perature rating for
38 C as given in the American Standard for
Steel Pipe Flanges and Flange Fittings for
the material and pressure standard involved.
For systems joined wholly with welded joints
the adjusted pressure rating shall be that for
ring joint facing for systems joined wholly or
partly with flanged joints the adjusted
pressure rating shall be that for ring joint
facing. for systems joined wholly or partly
with flanged joints the adjusted pressure
rating shall be that for the type of facing
used.
6.16 Expansion and Flexibility
a.
224
Piping systems are subject to a diversity of
loadings creating stresses of different types
and patterns, of which only the following
CHAPTER 11
-
PIPING
more significant ones need generally be
considered in piping stress analysis:
1.
Pressure, internal or external
2.
Weight of pipe, fittings and valves,
containing fluid and insulation, and
other external loadings such as
wind.
3.
Thermal expansion of the line.
joint efficiency maybe disregarded
calculating expansion stresses.
6.17 General
c.
d.
Materials. The thermal expansion range
shall be determined from the Table
11.6.16.2 as the difference between the unit
expansion shown for the maximum normaloperating metal temperature and that for the
minimum
normal-operating
metal
temperature (for hot lines this may usually
be taken as the erection temperature). For
materials not included in this table,
reference shall be made to authority source
data, such as publication of the National
Bureau of Standards. The cold and hot
moduli of elasticity, Ec and Eh, and the
moduli of torsional rigidity, Gc and Gh,
respectively, may be taken as the values
shown for the minimum and maximum
normal operating metal temperatures in
Table 11.6.16.2a for ferrous and Table
11.6.1 6.2b for non-ferrous materials.
For flexibility calculations, Poisson’s ratio
may be taken as 0.3 at all temperatures for
all ferrous materials.
Piping systems shall be designed to have
sufficient flexibility to prevent thermal
expansion from causing:
a.
The first two loadings produce
sustained
stresses which
are
evaluated by conventional methods.
The stresses due to thermal
expansion on the other hand, if of
sufficient initial magnitude will be
relaxed as a result of local flow in
the form of yielding or in the form of
creep. The stress reduction which
has taken place will appear as a
stress or reversed sign in the cold
condition.
b.
in
1.
Failure from over-stress
piping material or anchors
2.
Leakage at joints
3.
Detrimental distortion of connected
equipment resulting from excessive
thrusts and moments.
b.
c.
of
the
Flexibility shall be provided by
changes of direction in the piping
through the use of bends, loops,
and off-sets; or provision shall be
made to absorb thermal strains by
expansion joints of the slip joints or
bellows type. If desirable, flexibility
may be provided by increasing or
corrugating portions or all of the
pipe. In this case, anchors or ties of
sufficient strength and rigidity shall
be installed to provide for end forces
due to fluid pressure and other
causes.
Basic Assumptions and Requirements
1.
Formal calculations or model tests
shall be required when reasonable
doubt exists as to the adequate
flexibility of a system.
Each
problem shall be analyzed by a
method
appropriate
to
the
conditions.
No hard and fast rule can be given
as to when as analysis should be
made. However, in the absence of
better information the need for a
formal stress analysis for a twoanchor system of uniform pipe size
is indicated when the following
approximate
criterion
is
not
satisfied:
The S values, Sc and Sh at the minimum
and
maximum
operating
metal
temperatures, respectively, to be used for
determining the allowable expansion stress
range SA shall be taken for the type of
piping system involved from the applicable
tables in the respective sections of the code.
In the case of welded pipe, the long itudinal
DY
(L-U)
2
225
0.03
—
a)
.
.
0
0
0
0
0
0
0
0
0
0
0
0
A
B
A
B
A
B
A
B
A
B
A
B
A
B
A
B
A
B
A
B
A
B
A
B
Intermediate alloy steels;
5 Cr. Mo. thru 9 Cr. Mo.
Austenitic stainless steels
Straight chromium stainless steels;
12 Cr, 17Cr. and 27Cr.
25 Cr. —20 Ni.
Monel
67 Ni.- 30 Cu
Monel
66 Ni. 29 Cu.
Al u mm urn
Gray Cast iron
Bronze
Brass
Wrought iron
Copper-Nickel
(70—30)
-
0
70
A
B
Coefficient
.
9.00 9.08
11.12 12.31
9.52 9.70 9.88 10.04
11.77 13.15 14.58 16.02
9.30 9.50 9.70 9.89
11.50 13.00 14.32 15.78
8.92
9.95
9.34
10.4
9.10
10.1
8.81
8.78
9.16
9.12
8.90
8.86
8.68
7.60
8.96
7.85
8.70
7.62
8.52
6.44
8.78
6.64
8.50
6.43
8.38
5.33
8.58
5.46
8.30
5.28
8.22
4.24
8.40
4.33
8.09
4.17
8.08
3.20
8.20
3.25
7.90
3.13
7.92
2.18
8.02
2.21
7.68
2.12
7.84
1.22
7.48
1.17
11.85 12.09
14.65 16.39
11.6
12.9
11.4
11.3
8.29
8.26
11.6
9.78
8.13
7.12
10.00 10.23 10.47 10.69 10.92
2.76 4.05 5.40 6.80 8.26
8.01
6.06
7.61
3.01
8.90
3.52
7.48
2.06
8.71
2.40
9.76
1.52
7.32
1.14
8.54
1.33
7.73
3.99
7.88
5.01
8.39
9.36
10.90 11.00
13.47 14.92
10.8
12.0
10.7
10.8
10.6
9.30
6.47
4.11
10.03 10.12 10.23 10.32 10.44 10.52
1.56 2.79 4.05 5.33 6.64 7.95
6.28
3.24
7.19
8.02
6.10
2.42
7.00
6.97
5.93
1.64
6.83
5.98
5.75
0.90
6.65
5.03
12.95 13.28 13.60 13.90 14.20
2.00 3.66 5.39 7.17 9.03
9.12 9.18
13.46 14.65
6.85
10.11
7.76
7.21
6.78
920
6.90
11.01
6.72
8.31
6.63
7.40
6.52
6.49
6.39
5.60
6.26
4.73
6.13
3.90
5.96
3.08
5.81
2.30
5.66
1.56
5.50
0.86
10.39 10.48 10.54 10.60
12.84 14.20 15.56 16.92
10.2
11.4
10.6
10.2
10.5
8.80
9.92
7.50
9.82
6.24
9.70
5.01
9.59
3.80
9.47
2.61
9.34
1.46
7.49 7.55
7.41
10.00 11.06 12.05
7.32
9.05
7.22
8.06
7.10
7.07
6.96
6.10
6.80
5.14
6.66
4.24
6.50
3.35
6.34
2.50
6.19
1.71
6.04
0.94
1100 1200 1300 1400
8.12 8.19 8.28 8.36
10.04 11.10 12.22 13.34
400
6.82
2.70
300
6.60
1.82
200
6.38
0.99
Temperature Range_— 70 F to
900 1000
800
700
600
7.23 7.44 7.65 7.84 7.97
8.89
4.60 5.63 6.70 7.81
in Going from 70 F to Indicated Temperature
500
7.02
3.62
Mean Coefficient of Thermal Expansion x lOb (In/In/F]
Linear Thermal Expansion (In./lOOFt)
Material
=
=
Carbon Steel;Carbon-moly steel
low-chrome steels (thru 3% Cr)
A
B
Table 11.6.1 6.2
Thermal Expansion Data
C,
z
-U
-.
—I
m
C,
-4
E
G*
Graycastiron
Notes:
°C
=
°F—32
1.82
Note: Multiply by 6.895 to get values in kPa.
*No data available.
E
G
E
G
lntermmediatecr-molysteels(5%9% Cr), austenitic stainless steel
Wrought iron
E
G
Carbon-Moly steels low cr-moly
steels through 3% Cr.
E
G
E
G
Carbon steels with carbon content
above 0.30%
Straight chromium stainless steel
(12cr, 17cr, 27 cr)
E
G
Modulus
Carbon steels with carbon content
0.30% or less
Material
.
13.4
29.5
11.8
29.2
11.4
27.4
10.6
29.9
11.6
29.9
11.6
13.2
28.6
11.6
28.7
11.2
27.1
10.4
29.5
11.4
29.5
11.4
27.7
10.7
12.9
28.2
11.5
28.3
11.0
26.8
10.3
29.0
11.2
29.0
11.2
27.4
10.6
12.6
27.7
11.4
27.7
10.8
26.4
10.1
28.6
11.0
28.3
10.9
27.0
10.4
12.2
27.0
11.2
27.0
10.5
26.0
9.9
28.0
10.8
27.4
10.7
26.4
10.2
—
—
11.7
26.5
10.9
26.0
10.1
25.4
9.7
27.4
10.6
26.7
10.3
25.7
9.9
11.0
25.8
10.6
24.8
9.6
24.9
9.5
26.6
10.2
25.4
9.8
24.8
9.6
10.2
23.0
9.9
23.1
9.0
24.2
9.2
25.7
9.9
23.8
9.2
23.4
9.0
21.1
8.2
23.5
8.9
24.5
9.4
21.5
8.3
18.5
7.1
E = Modulus of Elasticity Multiply Values by 10°
Modulus of Torsional Ridigity Mulfiply Values by 106
Temperature, Deg. F
70
200
300 400 500 600
700
800
900
=
27.9
10.8
G
Table 11.6.16.2a
Moduli of Elasticity and Torsional Rigidty for Ferrous Material
18.6
7.2
22.8
8.6
23.0
8.8
18.8
7.2
15.4
5.9
1000
15.6
6.0
21.9
8.3
20.4
7.8
15.0
5.7
13.0
5.0
1100
12.2
4.7
20.8
7.8
15.6
5.9
11.2
1200
19.5
7.3
1300
18.1
6.7
1400
z
C,
0
-U
-o
-l
m
C)
I
00
F..)
.
E
Aluminum
11.8
10.9
12.2
11.3
12.7
4.58
11.7
4.72
13.0
4.72
12.0
4.40
13.5
4.90
12.4
4.52
15.6
5.90
13.7
5.10
12.7
4.65
15.8
6.00
13.9
5.25
12.9
4.82
16.0
6.03
14.0
5.27
13.0
4.89
E
G
E
G
E
G
Copper
99.98% Cu.
Commercial brass
66 cu, 34 m
Leaded tin bronze
88 cu, 6 an, 1.5 pb, 4.5 zn
Notes:
°C
°F—32
1.82
Note: Multiply by 6.895 to get values in KPa.
*No data available.
13.7
14.2
14.7
5.30
15.1
5.45
15.4
5.65
10.4
3.8
10.6
3.9
10.6
3.9
G
8.5
3.1
9.5
3.5
10.2
3.7
15.3
16.2
16.7
17.2
17.6
18.0
18.4
18.8
18.9
E
G*
Copper—Nickel
80—20,70—30
13.0
14.3
16.0
18.6
21.0
7.9
23.1
8.2
24.7
8.5
25.4
8.7
25.6
8.9
25.8
9.1
1200
1100
1000
900
800
26.0
9.3
Temperature, Deg. F
700
600
500
26.0
9.5
400
300
200
100
26.0
9.5
70
—
E
G
Modulus
—
E Modulus of Elasticity Multiply Values by 106
Modulus of Torsional Rigidity Multiply Values by 106
Monel67Ni—300u
66 Ni —29 Cu, Al
Material
G
=
Table 11.6.16.2b
Moduli of Elasticity and Torsional Rigidity for Non Ferrous Material
G)
z
-
-
m
-I
C-)
I
CHAPTER 11
Where:
D
=
nominal pipe size, 1mm
Y
=
resultant of movements to be
absorbed by pipe line, mm
U
=
anchor distance (length of straight
line joining anchors), metre.
L
1.
2.
3.
4.
5.
=
-
PIPING
6.18 Stresses and Reactions
a.
Using the foregoing assumptions, the
stresses, and reactions due to the
expansion shall be investigated at all
significant points.
The expansion stresses shall be combined
in accordance with the following formula.
developed length of line axis,
metre.
SE
+ 45t2
Where:
In calculating the flexibility of a
piping system between anchor
points, the system shall be treated
as a whole. The significance of all
parts of the line and of all restraints
such as solid hangers or guides,
including intermediate restraints
introduced for the purpose of
reducing moments and forces on
equipment or small branch lines
shall be recognized.
Calculations shall take into account
stress-intensification factors found
to exist in components other than
plain straight pipe. Credit may be
taken for the extra flexibility of such
components. In the absence of
more directly applicable data, the
flexibility factors shown in Fig.
11.6.17.3(c) may be used.
S
=
Sb
S
=
M
Z
=
=
=
IZ
M 12Z
=
Mb
iMb
=
=
resultant bending stress kPa
torsional stress
resultant bending moment, newtonmetre.
torsional moment, newton-metre
section modulus of pipe (m
)
3
stress intensification factor
b.
The maximum computed expansion stress,
SE based on 100 per cent of the expansion
and Ec for the cold condition shall not
exceed the allowable stress range, SA:
Where:
=
Dimensional properties of pipe and
fittings
as
used
in
flexibility
calculations, shall be based on
nominal dimensions. The pressure
stresses for services subject to
severe corrosion shall be based on
the reduced thickness of the pipe.
f (1.25 Sc
+
0.25 Sh)
In the above formula.
S
S
The total expansion range from the
minimum of the maximum normaloperating temperature shall be used
in all calculations, whether piping is
cold sprung or not. Not only the
expansion of the line itself, but also
linear and angular movements of
the equipment to which it is
attached, shall be considered.
allowable stress (S value) in the
hot condition
=
allowable stress (S value) in the
hot condition
h =
Sc and
f
Calculations for the expansions
stresses SE shall be based on the
modulus of elasticity Ec at room
temperature.
=
are to be taken from the table
in the applicable sections of the
code.
h
5
stress-range reduction factor for
cyclic conditions. In the absence
of more applicable date, the
values of f shall be taken from
the following table:
Attach Fig. 11.6.1.7.3(c) and Fig.
For graph for k and i.
229
CHAPTER 11
000
000
000
000
000
000
and
and
and
and
and
and
PIPING
modulus of elasticity
temperature E.
Stress Reduction
Factor f
Total No. of Full Temp.
Cycles Over Expected life
7
14
22
45
100
205
-
1.0
0.9
0.8
0.7
0.6
0.5
less
less
less
less
less
less
R = CR, or
Rc
(1-sh
\.
C
=
SE =
By the cross-sectional area of the pipe wall
—d
2
(D
)
Eh =
modulus of elasticity in hot
condition
=
range of reactions
corresponding to the full
expansion range based on
EC.
Rc and Rh represent the maximum
reactions estimated to occur in the
cold and hot conditions,
respectively.
In which
P
=
internal pressure, kPa
d
=
D
=
1.
cold spring factor varying
from zero for no cold
spring to one for 100 per
cent cold spring
maximum computed
expansion stress
modulus of elasticity in the
cold condition
R
pd2
D—d
2
longitudinal pressure stress, kPa
EhJ
Ec =
rid
F= p 2
4
=
•
Where:
Where the sum of these stresses is less
than Sh the difference between Sh and this
sum may be added to the term 0.25 Sh in
the above formula. The longitudinal
pressure stress Sep shall be determined by
dividing the end force due to internal
pressure:
Sep
Se
Whichever is greater, and with the
further condition that:
The sum of the longitudinal stresses due to
pressure, weight and other sustained
external loadings shall not exceed Sh.
SepL
A
room
Rh=
By expected life is meant total number of
years during which system is expected to be
in active operation.
A=u
4
or
at
c.
nominal outside diameter of the pipe
minus two times the normal wall
thickness in mm.
The design and spacing of support shall be
checked to assure that the sum of the
longitudinal stress due to the weight,
pressure, and other sustained external
loading does not exceed Sh.
Section 7.0 Industrial Gas and Air Piping
Systems
nominal outside diameter of pipe, mm
The reactions (forces and moments)
Rh and R in the hot and cold
conditions, respectively, shall be
obtained as follows from the
reactions R derived from the
flexibility calculations based on the
7.1
This industrial air and gas in mines, power
plants, industrial and gas manufacturing plants.
a.
230
Piping with metal temperature above 232°C
or below —2.9 °C.
CHAPTER 11
-
PIPING
Fig. 11.6.1.7.3(c) Flexibility Factor k and Stress Intensification Factor i
Flexibility
Factor k
Stress Lot.
Factor i
Welding elbow 1, 2,3
or pipe bend
1.65
h
0.9
213
h
Closely spaced mitre bend 1, 2, 4
s < r (1 + tan a)
1.52
.
.
Description
Widely spaced mitre bend 1, 2, 4
s> r (1 + tan a)
.
Flexibility
Characteristic h
.
Sketch
.
r
.
2h
13
1.52
h
.
0.9
213
h
Weldingteel.2
perASAB16.9
.‘
,
2
.
.
2h
13
Reinforced fabricated tee 1, 2
with pad or saddle
0.9
213
h
1
.
P4D
Unreinforced
fabricated tee 1 .2
0.9
3
h
Butt welded joint, reducer,
or welding neck flange
1
1.0
Double-welded joint, reducer,
or socket weld flange
1
1.2
Fillet welded joint, or singlewelded socket weld flange
.3
Lap joint flange (with
ASA B16.9 lap joint stub)
1
1 .6
Screwed pipe joint
or screwed flange
1
2.3
Corrugated straight pipe, or
corrugated or creased bend
5
1
2.5
231
r
CHAPTER 11
7.2
-
PIPING
b.
Air piping systems operating at pressures of
207 kPa or less.
Type of Pipe
(mm)
Value of C in Inches
c.
Piping lines with firebrick or other refractory
material used for conveying hot gases.
Threaded steel, wrought-iron
Depth of thread or
0.05 (1.7mm)
whichever is larger
Grooved steel, wrought-iron
Depth of groove
Plain end steel or wrought-iron
0.05 (1.7mm)
Wall thickness of Pipe
The minimum thickness of pipe wall required
shall be determined by the following formula for
the designated pressure and for temperature not
exceeding 232 C.
S
=
=
=
7.3
PD
2S + 0.8P
tm
where: P
D
outside diameter of pipe in inches (mm)
Effective Yield Strength (K)
The effective yield strength K of steel or
wrought-iron pipe maybe determined by taking
the product of Y, the stipulated minimum yield
strength, and E, efficiency of the longitudinal
joint. The value of E shall be taken from the
following:
allowable,
maximum
in kPa.
pressure
operating
The value obtained maybe
rounded to the next higher
unit of 10. The maximum
allowable operating pressure
computed with S values
this
under
permitted
exceed
not
shall
paragraph,
two-thirds of the mill test
service
a
for
pressure
temperature of 38°C or less
and five-ninths of the mill test
service
a
for
pressure
temperature of 232°C.
Specification
Pipe Type
ASTM A -53
Seamless
Electric Resistance Welded
Furnace Lap Welded
Furnace Butt Welded
Seamless
Electric Fusion Welded
Electric Resistance Welded
Electric Fusion Welded
Electric Fusion Welded
Seamless
Electric Resistance Welded
Electric Flash Welded
Furnace Lap Welded
Furnace Butt Welded
Seamless
Electric Resistance Welded
Electric Flash Welded
Submerged Arc Welded
ASTM A -106
ASTM A -134
ASTM A -135
ASTM A -139
ASTM A -155
API 5L
maximum allowable hoop
stress in kPa, see Table
11.7.2
For steel or wrought-iron pipe (except butt
welded-manufactured under a specification not
listed in Table 11.7.2) the value of S shall be 0.6
K for a service temperature of 38°C or less or
0.52K for a service temperature of 232°C where
K is the stipulated minimum effective yield
strength calculated in the manner described in
Section 11.7.3.
tm
C
=
=
Factor
Number
1.00
1.00
0.80
0.60
1.00
0.80
1.00
0.80
1.00
1.00
1.00
1.00
0.80
0.60
1.00
1.00
1.00
1.00
Alternatively, the effective yield strength maybe
determined by internal hydrostatic pressure
tests on finished lengths of pipe or on cylindrical
samples cut from the results of such tests in
accordance with the following formula:
minimum pipe wall thickness in mm, i.e.,
nominal wall thickness less the
the
for
tolerance
manufacturing
on
from
available
Where
thickness.
hand or in stock, the actual measured
wall thickness maybe used to calculate
allowable operating
the maximum
pressure.
K
=Q
2t
Where:
corrosion in millimetre obtained from the
following:
232
K
=effective yield strength in kPa
CHAPTER 11
Py
=
pressure at the yield strength
of the pipe in kPa.
-
PIPING
Electric furnace or
open hearth (Class
1)
Bessemer
This maybe taken as the pressure required to
cause a volumetric offset of 0.2 per cent of as
the pressure required to cause a permanent
increase in circumference of 0.1 per cent at any
point, but other suitable methods of determining
that the stress in the steel has reached the yield
strength maybe used, provided such methods
conform
in all
respects to recognized
engineering practices. t = stipulated nominal
pipe wall thickness in mm D = stipulated outside
diameter of pipe in mm.
Table 11.7.2 Maximum Allowable Stresses for Pipe
in Gas and Air Piping Systems
Material
Specification
Grade A
Grade B
Butt-welded wroughtiron
Red brass pipe
18,000
21,000
18,000
21,000
15,600
18,200
15,600
18,200
ASTMA-120
API 5L
API 5L
API 5L X
5
15,000
18,000
21,000
0.6Y°
13,000
15,600
18,200
ASTM A-155
ASTM A-155
ASTM A-155
14,400
16,200
18,000
14,400
16,800
3
0.48Y
12,500
14,050
15,600
Double-submerged arc
welded
ASTM A-139
ASTM A-139
ASTM A-134
0.60Y°
ASTM A-135
ASTMA-135
ASTMA-53
ASTMA-53
API-5L
API-5L
API 5LX°
18,000
21,000
18,000
21,000
18,000
21,000
0.51Y°
15,600
18,190
15,600
18,190
15,600
18,190
Open hearth or electric
furnace
ASTM A-53
12,000
10,400
Electric furnace or
open hearth CIassl
API 5L
12,000
10.400
ASTM A-53
API 5L
ASTMA-120
14,400
14,400
12,000
12,500
12,500
10,400
Electric Resistancewelded steel:
Grade A
GradeB
Grade A
GradeB
GradeA
Grade B
Butt-welded Steel:
Open hearth or
electric furnace
ASTM A-53
9,000
9,350
7,800
ASTM A-72
11,500
10,000
ASTM A-72
API 5L
8,650
8,650
7,500
7,500
B
B
B
B
1 50°F:250°F:350°F:400°F
(66°C): 121°C: 1 77°C:240°C
10,000:10000:7.500:3,750
7,500:6,250:5,625:3,750
7,500:6,250:5,625:3,750
-43
-42
-68, B -75,
-88
Refrigeration piping shall be understood to
comprise all refrigerant and brine piping,
whenever used and whether erected on the
premise or factory assembled.
8.2
Minimum Design Pressures for Refrigerant
Piping
a.
Piping Systems for refrigerants shall be
designed for not less than the pressures
given in Table 11.8.2.1.
b.
For refrigerants not listed in Table 11.8.2.1
the design pressure for the high-pressure
side shall be not less than the saturated
vapour pressure of the refrigerant at 54 °C.
The design pressure for the low-pressure
side shall be not less than the saturated
vapour pressure of the refrigerant at 32 °C.
For refrigerant not listed in Table 11.8.2.1 &
having a critical temperature below 54°C,
the design pressure for the high pressure
side shall be not less than 1.5 times the
critical pressure and the design pressure for
the low-pressure side shall be not less than
the critical pressure. In no case shall be
design pressure be less than 270 kPa.
c.
Piping systems for brine shall be designed
for the maximum pressure which can be
imposed on the system in normal operation,
but not less than 689.5 kPa including for
cast-iron pipe, the water hammer allowance
as shown in Table 11.8.2.3.
d.
For working temperatures below 18°C, an
allowance for brittleness of castings,
forgings, bolting, and pipe shall be made as
follows:
Lap-Welded Steel:
Bessemer
10,800
9,000
8.1
12,500
14,550
0.42Y°
API 5LX°
ASTM A-53
ASTM A-120
Copper Tubing
Electric Fusion
Welded Steel
Grade A
Grade B
Grade C
Ordinary
Grade A
Grade B
7,800
Copper Pipe
232°C
ASTMA-106
ASTMA-106
ASTM A-53
ASTM A-53
9,000
Section 8.0 Refrigerator Piping System
Maximum Allowable Stresses
in Psig for Temperatures not to
Exceed 2,4
38°c
Seamless Steel:
GradeA
Grade B
Grade A
Grade B
Lap-welded wroughtiron
API 5L
7,800
233
CHAPTER 11
and
WROUGHT-IRON,
IRON,
CAST
CARBON STEEL ferrous materials shall
pressure including
have the design
increased 2
hammer
water
for
allowance
percent for each degree below 18°C and
shall not be used below 73°C.
-
Plain-end, steel or wroughtiron pipe
1 in. size and smaller
Sizes larger than 1 in.
1.27mm
1.651 mm
Plain-end non-ferrous pipe
or tube
Zero
—
COPPER,
adjustment.
8.3
BRASS,
BRONZE.
PIPING
No
In the case of cast-iron pipe the minimum values
of the water hammer allowance to be added to P
are given in Table 8.6.2.3
*
Thickness of Pipe
Table 11.8.2.1
Minimum Design pressure (Psi) for Refrigerant Piping
The minimum thickness of pipe wall required
shall be determined by the following formula:
.
tm
2S
+
PD
O.8P
.
Material
Where:
tm
=
maximum internal service pressure in
kPa (plus allowance for temperatures
as provide in Sec. 11.8.2.4 and water
hammer allowance for cast-iron pipe
as provided in Sec. 11.8.2.3). The
value of P shall not be taken at less
than 689.5 kPa for any condition of
service or material.
P
D
minimum pipe wall thickness in mm
=
outside diameter of pipe in mm
Chemical
Formula
Group I
Carbon dioxide
Dichiorodifluoromethana
(Freon- 12)
2
CO
CCI
F
2
Dichioromethane (Carrene
No.1) Methylene chloride)
High
Low
Pressure
Side
Pressure
Side
1,500
170
1,000
85
C1
2
CH
30
30
Dichloromonofluoromethane
F
2
CH CI
(Freon—21)
50
30
Dichlorotetrafluoromethane
(Freon—114)
C1
2
C
4
F
55
30
Monocholorodifluoromethane
2
CH Cl F
(Freon 22)
285
150
30
30
30
30
3
NH
C(
H
2
C
CI
5
H
2
C
1
C
3
CH
3
HCOOCH
2
SO
300
30
40
150
30
115
150
30
30
75
30
45
10
H
4
C
C
6
H
2
4
H
2
C
CH
)
3
(CH
8
H
3
C
65
1,000
1,300
90
300
30
640
1,050
40
150
—
S
C
=
=
allowable stress in material due to
internal pressure, kilo Pascal Table
11.8.3
Trichloromonoflouromethane
3
CCI
(Freon 11)
—
Trichlorotrilluoro-ethane
threading, mechanical
Allowance
strength, and/or corrosion, in mm
obtained from the following list.
C1
2
C
3
F
fr
Type of Pipe
Group 2
Ammonia
Dichloruethylene
Ethyl Chloride
Methyl Chloride
Methyl Formate
Sulphur Dioxide
Value of C in mm
Cast-iron pipe cetrifugally cast
or cast horizontally in green
sand molds
3.556mm
Group 3
Cast-iron pipe, pit-cast
4.572mm
Butane
Ethane
Ethylene
Isobutane
Propane
Threaded steel, wrought-iron
or non-ferrous pipe
3/8 in, and smaller
1/2 in. and larger
1.27mm
Depth of thread
Grooved steel, wrought-iron
or non-ferrous pipe
Depth of groove mm
Note: Multiply value by 6.895 to obtain P in kPa.
8.4
Piping of Pressure Relieving Devices
The most important design factor about
pressure relieving devices is the underlying
234
CHAPTER 11
-
PIPING
principle of intrinsic safety. They must “fail safe”
or not at all. Therefore, the solution to problems
in pressure relief piping must be based on
sound design practices. Because failure is
intolerable, simplicity and directness of design
should be encouraged as a mass to reliability.
a.
The inlet and outlet piping can reduce the
capacity of the device below a safe value.
b.
The operation of the device maybe
adversely affected to the point where the
opening or closing pressure is altered. In the
case of safety valves*, premature leaking or
“simmering” may occur at pressures less
than the set pressure or chattering may
occur after the valve opens.
c.
The reaction thrust at the same time the
device starts to discharge can cause
mechanical failure of the piping.
d.
Good design saves maintenance pesos.
There are at least four good reasons why the
installation of pressure safety valves and disc
should be engineered with care:
Table 11.8.3
Allowable S Values for Pipe and Tubing
in Refrigerating Systems
Material
Steel Pipe (Grade A)
and tubing
Seamless
Specification
ASTM A —53
—
Values of
PSI
Pipe
ASTM A —83— Tube
ASTM A —120— Pipe
ASTMA—179—Tube
ASTM A —192— Tube
ASTM A —106 Pipe
API 5L Pipe
ASTM A —53— Pipe
8.5
In order to operate satisfactorily, a safety valve
must be mounted vertically. It should be directly
on the vessel nozzle or on a short connection
fitting that provides direct and unobstructed flow
between the vessel and the valve. Safety valves
protecting piping systems should of course be
mounted in a similar manner. The device may
never be installed on a fitting having a smaller
inside diameter than the safety valve inlet
connection.
—
—
Steel Pipe (Grade B) and
Tubing
Seamless
Steel Pipe, Lap Welded
ASTM A 106— Pipe
ASTMA—210—Tube
ASTM A —53 Pipe
ASTM A— 120— Pipe
API 5L Pipe
ASTM A —53— Pipe
ASTM 120—Pipe
ASTM —135— Pipe
Grade A
Grade B
ASTMA—178)Tube
ASTMA—214—Tube
ASTM A —226— Tube
Steel Pipe, or Tube,
Electric-Resistance
Welded
Steel, or Pipe Seamless
Alloy
Grades TP 321
TP347
Steel Tube-Electric
Resistance-Welded
Alloy, Grades TP 321
TP 347
(Note: 085 joint Efficiency)
Steel Tube, cooper Brazed
Wrought Iron, Lap Welded
Wrought Iron, Butt welded
Cast-Iron Pipe, PitCast*
Cast-iron, Centrifugally Cast
or cast horizontally
in Green Sand Molds
**Brass Pipe, Seamless
Red Brass
**Copper Pipe, Seamless
**Copper Tubing, Seamless
12,000
—
15,000
—
—
Steel Pipe, Butt Welded
9,000
6,800
10,200
12,750
10,200
10,200
10,200
Pipe Diameter Sizes
ASTMA—312—Pipe
ASTMA-213—Tube
18,750
ASTM a-249
15,900
ASTM A 254
Class I
Class II
ASTM A —72
API 5L
ASTM A —72
AS 21.2
100mm to 250mm mcI.
300mm to 350mm mcI.
400mm to 450mm mcI.
500mm
600mm
750mm
900mm
lO5Ommtol500mm
—
FSB WW
ASTM
ASTM
ASTM
ASTM
ASTM
B
B
B
6
B
—
P
—
6,000
3,000
8,000
6.000
4,000
421
-43
-42
-88
-68
-208T
Safety Valve Inlet Piping
8.6
827 kPa
758 kPa
689.5 kPa
621 kPa
586 kPa
552 kPa
517 kPa
483kPa
Pressure Drop
The pressure drop between the vessel and
safety valve inlet flange should not be so large
that the valve is “starved” or chattering will
result. The following limitations are suggested:
6,000
7,000
6,000
6,000
6,000
6,000
a.
The pressure drop due to friction should not
exceed 1 percent of the accumulated
relieving pressure.
b.
The pressure drop due to velocity head loss
should not exceed 2 percent of the
accumulated relieving pressure.
*Castiron is allowed only for non-volatile refrigerants.
**Brass pipe,
Water Hammer
Allowance, kPa
copper pipe seamless copper tubing seamless,
temperature limit 250 o (121
C).
0
NOTE: Multiply values by 6.895 to get S in kPa.
235
CHAPTER 11
-
PIPING
Table 11.8.7
Standard Pipe Support Spacing (unless otherwise
specified)
Some safety valve manufacturers suggested
a maximum total pressure drop of 2 percent
of set pressure. In the absence of test data,
it is recommended that this more
conservative limit be used.
Hanger Spacing
Pipe Size
Rod Size
.
These recommendations are based on a
blowdown of a 4 percent. Within this limits, if
the blowdown setting is increased, the
increased
maybe
drop
pressure
proportionately. Remember however, that
pressure lost in the inlet piping must be
taken into consideration when sizing the
safety valve. Pressure loss in the discharge
piping should be minimized by running the
line as directly as possible. Use long-radius
bends and avoid close-up fittings. In no case
may the cross-sectioned area of the
discharge pipe be less than that of the valve
outlet.
8.7
6 ft. on centers
8 ft. on centers
10 ft. on centers
loft, on centers
10 ft. on centers
loft, on centers
lOft, on centers
10 ft. on centers
Up to 1 in.
1-1/4 in to 2 in.
2-1/2 in to 4 in.
5in.to6 in.
8 in. to 10 in.
12 in.to 14 in.
16 in. to 18 in.
20 in. to 24 in.
2
Vertical risers shall be supported from
the building construction by means of
approved pipe clamps of U-bolts at
every floor. Provide slide guides for
pipes subject to thermal expansion.
Supports shall be of adequate size
structural steel shapes or sections
where pipe clamps are too short to
connect to the building.
Pipe Anchors and Restraints:
1.
2.
236
lbs.
lbs.
lbs.
lbs.
lbs.
lbs.
lbs
lbs.
The copper tubing and fittings (for
be
shall
lines)
air
instrument
supported not more than 5 feet on
centers or as shown on the drawings.
B.
The major stresses to which the discharge pipe
is subjected are usually due to thermal
expansion and discharge reaction forces. The
sudden release of compressible fluid into a
multi-directional discharge pipe produces an
impact load and bourdon effect at each charge
of direction. The piping must be adequately
anchored to prevent sway or vibration while the
valve is discharging.
15.0
50.0
200.0
400.0
800.0
1,500.0
2,000.0
3,500.0
1.
Piping Supports
Supports for discharge piping should be
designed to keep the load on the valve to a
minimum. In high temperature service, high
loads will cause permanent distortion of the
valve because of creep in the metal. Even at low
temperature, valve distortion will cause the valve
to leak at pressures lower than the set pressure
and result in faulty operation. The discharge
piping should be supported free of the valve and
carefully aligned so that the forces acting on the
valve will be at minimum when the equipment is
under normal operating conditions. Expansion
joints or long radius bends of proper design and
cold spring should be provided to prevent
excessive strain.
One 1/4 in.
One 3/8 in.
One 1/2 in.
Two 5/8 in.
Two 5/8 in.
Two% in.
Two%in.
Two % in.
The maximum weight per span is based
on bigger steel pipe size weight full of
water fittings and insulated.
NOTES: A.
Safety valves, although they may not be
“delicate
of
heading
under
included
are
They
instruments.
nonetheless
,
instruments”
required to measure within three percent and to
perform a specific control function. Excessive
strain on the valve body adversely affects its
ability to measure and control.
Max.
Wt./Span
Where piping is subject to thermal
expansion and where expansion
loops, expansion joints and offsets are
indicated, provide suitably designed
pipe anchors to limit pipe thermal
expansion and over stressing of pipe
and adjacent connecting structures.
a.
Rigid pipe anchors shall either be
welded type construction or clamp
bolted type whichever is suitable
to the requirement:
b.
Directional type pipe anchors
where pipe movement is allowed
in any one plate shall be designed
to prevent excessive stresses to
the pipe and interference with
adjacent pipes or structure.
Piping restraints shall be provided to
prevent unnecessary pipe movements
CHAPTER 11
-
PIPING
due to vibration and seismic forces
and damage to pipe joints such as
cast iron pipe, soldered copper pipes
and others as required.
8.8
negligible. However, since it is usually
possible to trap air or gas in any pressure
system, it is recommended that K = 104 be
used in the above formulas as a basis
design for liquid service.
Reaction Forces
Here are values of K which can be safely
used for common fluids.
The total stress imposed on a safety valve or its
piping is caused by the sum of these forces:
Fluids
a.
Internal pressure
b.
Dead weight of piping
c.
Thermal expansion or contraction of either
the discharge line of the equipment upon
which the valve is mounted and
d.
The bending moment cause by the reaction
thrust of the discharge.
The magnitude of the reaction force
resulting from the instantaneous release of a
compressible fluid maybe calculated from
the two simple formulas given below.
For safety valve:
=
(K
+
0.2) AP
1
For safety disc:
1
F
=
0.63 (K
Where:
1
F
=
Reaction force, Kg
A
1
P
K
=
0.2) A P
1
inlet pressure at time of opening,
kPa (set pressure plus 14.7)
ratio of specific heats, CpICv.
Note: Psi x 6.895
=
1.4
1.3
1.3
1.67
0.53
0.55
0.55
0.49
Compressor Piping
Because of the ever present vibration
problems at reciprocating compressors, pipe
supports have a very important role in piping
design. Supports independent of any other
foundation or structure is almost mandatory.
Pipe systems “nailed down” close to grade is a
much
preferred arrangement.
If badly
designed compressor piping has to be
corrected after start-up of the plant, it can
become very expensive.
Area of valve orifice or disc., sq.
mm.
=
=
+
8.9
Rc
Piping in a compressor circuit should connect
directly point to point; bends instead of elbows
give less friction loss and less vibration;
angular branch connections eliminate hard
tees and give a smoother flow; double offsets
for directional change should be avoided;
closely integrated intercoolers with the
machine
minimizes
piping;
pulsation
dampeners should be located on the cylinders
without any interconnecting pipe; knockout
drums should be adjacent to the machine;
several aftercoolers or exchangers in the
circuit should be stacked as much as possible
for a direct gas flow; and equipment in the
circuit should be in process flow sequence.
All of these stresses except the latter are
common to practically every problem in
piping stress analysis.
1
F
Air and diatomic gases
Steam
, CC
3
NH
, CH
2
, and SO
4
2 vapors
Helium, Argon
K
kPa.
If it is possible for air to be relieved from the
system under special conditions, use a
minimum valve of K = 1.4 for design.
Calculation of the reaction force for liquid
service demonstrates that this force is
237
CHAPTER 12
-
METROLOGY
Chapter 12
METRO LOGY
second-ampere). In 1960 the CGPM, formerly
named this system the Systeme International d’
Unites, for which the abbreviation is SI in all
languages.
Section 1.0 Purpose and Scope
To familiarize all practitioners with the concepts and
techniques of measuring instruments. It covers the
application of metrology in all industries, which
concerns with the fundamental standards and
techniques of measurements, and with the scientific
principles of the instrumentation involved.
At the present time most of the industrially
advanced metric-using countries are changing
from their traditional metric system to SI.
The SI, like the traditional metric system, is
based on decimal arithmetic. For each physical
quantity, units of different size are formed by
multiplying or dividing a single base value by
powers of 10.
Section 2.0 Definitions
Degree of conformity of a
CorrectnesslAccuracy
measured or calculated value to some recognized
standard or specific value. The difference between the
measured and true value is the error of the
measurement. Precision is the repeatability of the
measuring process, or how well identically performed
measurement agree, which concept applies to a set of
measurements.
—
The SI is a coherent system, because the
product or quotient of any two units’ quantities in
the system is the unit of the resultant quantity.
For example in a coherent system in which the
meter is the unit of length, the square meter is
the unit of area.
Tolerance is the amount of
Tolerance/Allowance
variation permitted in the part of total variation allowed
in a given dimension while allowance is the minimum
clearance space intended between the mating parts
and represents the conditions of tightest possible fit.
—
A system of measurements, such as the Le
Systeme International d’ Unites (SI) satisfies
certain concepts, where units are used. The SI
system is a decimal system composed of six
base units, two supplemental units and
additionally derived units as given in Table 12.1,
SI System of Measurements in Table 12.2 for
easy reference, Table 12.3 are some conversion
factors commonly used, and Table 12.4 Multiple
and Sub-Multiple Units.
Standard Something that is set up and established
by authority as a rule for the measure of quantity,
weight, extent, value or quality.
—
Sensitively and readibility
SensitivitylReadibility
the measuring process.
with
are primarily associated
device to detect
measuring
of
a
ability
is
the
Sensitivity
small differences in a quality being measured, while
readibility is the susceptibility of a measuring device to
having its indication converted to a meaningful
number.
—
3.2
a.
Section 3.0 Measurement Concepts
3.1
Mechanics
The International System of Units (SI).
The Conference Generale des Poids et
is the body
Measures (CGPM) which
matters
international
responsible for all
concerning the metric system, adopted in 1954,
a rationalized and coherent system of units,
based on the four MKSA units (meter-kilogram
238
The use of the Metric SI System in
Mechanics Calculations. The SI system is a
development of the traditional metric system
based on decimal arithmetic; fractions are
avoided. For each physical quantity, units of
different size are formed by multiplying or
dividing a single base value by powers of
10. Thus, changes can be made very simple
by adding zeroes or shifting decimal points.
For example, the meter is the basic unit of
length; the kilometre is a multiple (1,000
meters); and the millimetre is a sub-multiple
(one-thousandths of a meter).
CHAPTER 12- METROLOGY
In the older metric system, the simplicity of a
series of units linked by powers of 10 is an
advantage for plain quantities such as
length, but this simplicity is lost as soon as
more complex units are encountered. For
example, in different branches of science
and engineering, energy may appear as the
erg, the calorie, the kilogram-meter, the literatmosphere, or the horse power-hour. In
contrast, the SI provides only one basic unit
for each physical quantity, and universality is
thus achieved.
There are six base-units, and in mechanics
calculations three are used, which are for
the basic quantities of length, mass, and
time, expressed as the meter (m), the
kilogram (kg), and seconds (s). The other
three base-units are the ampere (A) for
electric current, the Kelvin (K) for thermo
dynamic temperature, and the candela (Cd)
for luminous intensity.
The SI is a coherent system. A system of
units is said to be coherent if the product or
quotient of any two unit quantities in the
system is the unit of the resultant quantity.
For example, in a coherent system in which
the foot is a unit of length, the square foot is
the unit of area, whereas the acre is not.
Other physical quantities are derived from
the base-units. For example, the unit of
velocity is the meter per second (mis), which
is a combination of the base units of length
and time. The unit of acceleration is the
meter per second squared (mis
).By
2
applying Newton’s second law motion
force is proportional to mass multiplied by
acceleration
the unit of force is obtained
which is the kg 2
is This unit is known as
m
.
the Newton, or N. Work, or force times
distance, is the kg 2
is which is the joule,
m
,
(1 joule = 1 newton-meter) and energy is
also expressed in these terms. The
abbreviation for joule is J. Power, or work
per unit time, is the kg 2
is which is the
m
,
watt (1 watt = 1 joule per second = I
newton-meter per second). The abbreviation
for watt is W.
—
—
applied without introducing such numbers as
550 in power calculations, which, in the
English system of measurement have to be
used to convert units. Thus, conversion
factors largely disappear from calculations
carried out in SI units, with a great saving in
time and labor.
1.
Mass, weight, force, load. SI is an
absolute system, and consequently
it is necessary to make a clear
distinction between mass and
weight. The mass of a body is
measure of its inertia, whereas the
weight of a body is the force exerted
on it by gravity. In a fixed
gravitational field, weight is directly
proportional to mass, and the
distinction between the two can be
easily overlooked. However, if a
body is moved to a different
gravitational field, for example, that
of the moon, its weight alters, but its
mass remain unchanged. Since the
gravitational field on earth varies
from place to place by only a small
amount, and weight is proportional
to mass, it is practical to use the
weight of unit mass as a unit of
force, and this procedure is adopted
in both the English and older metric
systems
of
measurement.
In
common usage, they are given the
same name, and we say that a
mass of 1 pound has a weight of 1
pound. In the former case the pound
is being used as a unit of mass, and
in the latter case, as a unit of force.
This procedure is convenient in
some branches of engineering, but
leads to confusion in others.
As mentioned earlier, Newton’s
second law of motion states that
force is proportional to mass times
acceleration.
Because
an
unsupported body on the earth’s
surface falls with acceleration g (32
2 approximately), the pound
ft/s
(force) is that force which will impart
an acceleration of g Ws
2 to a pound
(mass). Similarly, the kilogram
(force) is that force which will impart
an acceleration of g (9.8 meters per
2 approximately), to a mass
second
of one kilogram. In the SI, the
newton is that force which will
The coherence of SI units has two important
advantages. The first is that of uniqueness
and therefore universality, has been
explained. The second is that it greatly
simplifies technical calculations. Equations
representing physical principles can be
239
CHAPTER 12
V
V
:
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
-
METROLOGY
) to a
2
impart unit acceleration (lm/s
mass of one kilogram. It is therefore
smaller than the kilogram (force) in
the ration 1 :g (about 1:9.8). This fact
has important consequences in
The
calculations.
engineering
factory now disappears from a wide
range of formulas in statics where it
was formerly absent. It is however
not quite the same g, for reasons
which will now be explained.
meters is RL Nm, or RL joules.
If this work were converted
entirely into kinetic energy we
2 and it is
could write RL = 1/2 MV
instructive to consider the units.
Remembering that the N is the
, we have
2
same as the kg m/s
2 which
(m/s)
kg
=
m
x
)
2
m/s
(kg
is obviously correct. It will noted
not appear
does
that g
anywhere in these statements.
The mass of a body is referred to as
M, but it is immediately replaced in
subsequent formulas by W/g, where
W is the weight in pounds (force),
which leads to familiar expressions
/2g for kinetic energy.
2
such as WV
In this treatment, the M which
appears briefly is really expressed in
terms of the slug, a unit normally
aeronautical
in
only
used
engineering. In everyday engineer’s
language, weight and mass are
regarded as synonymous and
/2g are
2
expressions such as WV
the
pondering
without
used
on
,
Nevertheless
distinction.
reflection it seems odd that g should
appear in a formula which has
nothing to do with gravity at all. In
fact the g used here is not the true,
local value of the acceleration due
to gravity, but an arbitrary value
which has been chosen as part of
the definition is not to indicate the
strength of the local gravitational
field, but to convert from one unit to
another.
In contrast, in many branches of
engineering where the weight of
a body is important, rather than
its mass, using SI units g does
appear where formerly it was
absent. Thus, if a rope hangs
vertically supporting a mass of
M kilograms the tension in the
rope is MgN. Here g is the
acceleration due to gravity, and
. The ordinary
2
its units are rn/s
numerical value of 9.81 will be
sufficiently accurate for most
The
earth.
on
purposes
valid
still
is
expression
elsewhere, for example, on the
moon, provided the proper value
of g is used. The maximum
tension the rope can safely
withstand (and other similar
properties) will also be specified
in terms of the newton, so that
direct comparison may be made
with the tension predicted.
Words like load and weight have
to be used with greater care. In
everyday language we might
say “a lift carries a load of five
people of average weight 70
kg”, but in precise technical
language we say that if the
average mass is 70 kg, then the
average weight is 70 gN, and
the total load (that is force) on
the lift is 350 gN.
In the SI the unit of mass is the
kilogram, and the unit of force (and
therefore weight) is the newton.
typical
are
following
(a) The
dynamics
in
statements
expressed in SI units:
A force of R newtons acting on
a mass of M kilograms produces
an acceleration of R/M meters
. The kinetic energy
2
per second
of a mass of M kg moving with
velocity V m/s is 1/2 Mi/kg
2 joules. The
(rn/s)2 or 1/ MV
work done by a force or R
newtons moving a distance L
If the lift starts to rise with
, the load
2
acceleration a m/s
+ a) N’ both g
350
(g
becomes
, the
2
and a have units of m/s
mass is in kg, so the load is in
, which is the
2
terms of kg m/s
same as the newton.
240
CHAPTER 12- METROLOGY
2.
Pressure and Stress.
These
quantities are expressed in terms of
force per unit area. In the SI the unit
is based on the newton per square
meter, (N/rn
). Similarly data used in
2
strength-of-materials
calculations
(Young’s modulus of elasticity, yield
strength and so on) are all
expressed in terms of the newton. It
has been recommended by the
International
Standards
Organization that the special be the
pascal (Pa). This recommendation
is subject to approval by the CGPM.
The basic unit N/rn
2 is very small, it
is only 0.15 x 10 lb/in
, hence the
2
2 ( 106 N/rn
kN/m
) are much more
2
frequently encountered. The latter is
sometimes written as N/mm
. In
2
some countries the bar = i0
2
5 N/rn
and hectobar =
2 are
N/rn
employed. The safest rule is to
convert to the basic unit before
starting any calculations.
a.
b.
c.
d.
e.
4.5
5.1
1. Rule
2. Combination set
3. Depth Gage
4. Vernier caliper
5. Micrometer
6. Measuring machine
—
a.
Shrink Rules commonly employed in the
pattern-making trade where the casting of
metals are involved, which automatically
take
into
consideration
the
shrink
allowances of the materials being cast.
b.
Hook Rule frequently used to assure the
user that the end of the workpiece is flush
with the end of the rule.
c.
Tapered rules
used in measuring inside
of small holes, narrow slots, and grooves.
Protractors
Sine Bar
Combination Set
Angle Gage Blocks
Dividing Head
5.3
Plane Surface Measurement
241
—
—
—
Calipers.
a.
Slide Calipers
consist of a stationary
integral with graduated beam on which the
movable jaws slides, with a reference point
for inside and outside reading.
b.
Vernier Calipers a measuring instrument
which can be used for taking both inside and
c.
Dial Caliper— directly reading callipers
which are accurate up to the thousandth of a
centimeter.
Calipers and Dividers
Telescopic Gages
Angular Measurements
a.
b.
c.
d.
e.
4.4
5.2
Instruments for transferring measurements
a.
b.
4.3
Rules
the most generally used graduated
measuring instrument in the industrial metrology
field for approximately determining linear
dimensions, which are made with various
dimensions, graduations, and accuracies. Rules
shall be manufactured or carbon steel or
stainless steel.
Direct Reading
(a) Mechanical
(b) Optical
Pneumatic
Hydraulic
Electric/Electronics
Lasers
Others
Secttion 5.0 Graduated Manual Measuring
Tools
Linear Measurement
a.
4.2
All-Purpose Special Measurement
a.
b.
c.
d.
e.
4.0 Classification of the Common
Measuring Instruments Used in Industry
4.1
Level
Combination Set
Surface Gage
Profilometer
Optical Flat
—
—
Vernier Height Gages
vertically-positioned
vernier calipers used in tool rooms, inspections
departments, or wherever layout and jig and
—
CHAPTER 12
-
METROLOGY
blade shape which are used for checking the
root diameter of circular form tools as well
as the diameter of circular form tools as well
as the diameter and depth of narrow slots,
keyways, recesses, etc.
fixtures work necessitate accurately measuring
or marking off vertical distances.
a.
b.
5.4
Vernier Depth Gages provide long range
accuracy for determining the depths of
holes, slots, and recesses as well as
measuring from a plane surface to
toolmaker’s buttons in locating center
distances.
—
used to
Gear Tooth Vernier Calipers
teeth
gear
of
thickness
line
pitch
check the
by measuring the tooth chord at a specific
distance (chordal addendum) from the top of
the gear tooth. The Gage consists of two
independently actuated Vernier calipers,
each having its own movable slide, but the
beams and the stationary jaw are made of a
common single piece. One of the slides has
the form of a plate, called the tongue of the
instrument, which contacts the top of the
gear tooth, by moving this slide, the Gage
can be adjusted to operate at the desired
addendum distance. The second slide,
integral with the movable jaw, carries out the
actual chordal thickness measurement at
the pitch line.
d.
allow the
Quick-adjusting micrometers
spindle to be slid quickly to any point within
their range which makes them particularly
efficient thousandths-reading micrometers
for checking work where a variety of
dimensions are involved.
e.
Screw thread micrometers are designed
to measure the pitch diameter of screw
threads to thousandths accuracy by the use
of a pointed spindle and double V-anvil
which are available for varying diameters of
work and each size normally covers a range
of the threads-per-centimeter.
f.
used for measuring
Inside micrometer
and other inside
holes
of
the diameters
dimensions, consists of a permanent contact
of
set
a
and
head
micrometer
interchangeable rods in various increments
which are seated snugly in the opposite end
of the head against a shoulder and locked
securely.
—
most useful close
Micrometer Calipers
tolerance measuring devices for quick and
accurate measurements to the thousandth part
of a centimeter.
—
a.
5.5
Outside Micrometer precision-measuring
instruments used in determining outside
measurements, and classified into (a)
Interchangeable anvil micrometers, (b)
Multiple anvil micrometers (c) High precision
indicating
Dial
(d)
micrometers,
reading
Direct
(e)
micrometers,
micrometers, (f) V-anvil micrometers, (g)
Disc-type micrometers, (h) Blade type
Quick-adjusting
(i)
micrometers,
thread
Screw
(j)
and
micrometers,
micrometers.
—
b.
are read
Direct-reading micrometers
directly in thousandths from figures
appearing in small windows on the barrel of
the micrometer, “tenths” (of thousandths)
however,
micrometers,
reading
direct
employ a vernier for establishing the “tenths”
figures.
c.
an
are
micrometers
Blade-type
which
in
adaptation of standard micrometers
the anvil and spindle ends are thinned to a
—
5.6
—
242
—
—
—
Protractor consists of a rectangular head
graduated in degrees along a semicircle, with a
blade pivoted on the center pin, any angle from
0 to 180° can be set.
a.
Combination protractor and depth gage
is a combination of a movable graduated
blade (depth gage) and a graduated
protractor head.
b.
Universal bevel protractor consists of a
round body with a fixed blade, on which a
graduated turret rotates. The turret is slotted
to accommodate an 18 or 30-centimeter
non-graduated blade. Through a locking
mechanism any desired angle and the blade
length can be seen. This tool has a vernier
reading to 5 minutes and can be furnished
with or without a fine adjustment feature.
The dial of the protractor is graduated
around a complete circle and an angle up to
360°can be laid out accurately.
Dial Indicator a dial indicator is composed of
a graduated dial, spindle, pointers and a
satisfactory means of supporting or clamping it
firmly, which is used to measuring inaccuracies
—
CHAPTER 12- METROLOGY
in alignment eccentricity, and deviations on
surfaces supposed to be parallel. In gaging
work, it gives a direct reading of tolerance
variations from the exact size. Dial indicators are
classified as American Gage Design standard
indicators and dial test indicators.
a.
5.7
transferred to a graduated measuring tool to
determine measurement required.
Dial Test Indicators commonly known as
the toolmaker’s indicators which are smaller
than the smallest A.G.D. standard indicator
and because of its small size and its thin
tapered body, it can be employed in many
places not accessible with other indicators
and also used as an accessory with many
machine tools.
6.2
Bevels
consists of two three-non-graduated
slotted blades with one or two screws and
knurled nuts connecting them, by loosening the
nuts, the blades can be set to varying angles.
With this tool, one can easily transfer angles
from a master to a work piece or vice versa with
moderate accuracy.
6.3
Trammels used in sizes beyond the range of
dividers, consist of a long bar on which two arms
or trammels slide. Trammels are designed for
layout work and use inside, outside or divider
legs and some are furnished with ball points, to
permit working from holes. Some are also
furnished with an adjustable screw on one of the
trams, for fine adjustment of the point for easy
setting.
6.4
Gages
a gage is a device used to determine
whether the part has been made to the tolerance
required and does not usually indicate a specific
dimension.
—
Planimeter
the planimeter (planekator) is a
tool for checking the flatness of plane surfaces
to tenths-of-thousandths of a centimeter and
consists of a diabase straight edge, an
adjustable mounting for the straight edge, and a
0.00005 cm. reading indicator. The straight edge
is always in the same reference plane at every
position on the surface being checked. Readings
are taken under the straight edge and recorded
directly into the contour chart of the plane being
checked. Points of equal height are connected
to form a visual picture of the high and low
points in the plane. Extreme care shall be taken
in handling this gage to retain its accuracy and
not to damage the surface being checked.
—
—
—
—
a.
Telescoping gages cover a range from 4
mm to 150 mm. Two types are commonly
used in industry. One type has a handle with
one stationary contact and one spring
plunger contact with locking device set at
right angles to the handles while the other
one has a handle with two plunger-contacts
at right angles to the handle.
b.
Surface gages consist of a ground
rectangular steel base with a round upright
rod and a fine adjustment feature in the
base. A universal sleeve holds a scriber
which can be set to any position and locked
in that position. The surface gage is used in
layout work for scribing lines on vertical and
horizontal surfaces and may also be used in
inspection work as height or depth gage.
Section 6.0 Non-Graduated Manual
Measuring Tools
6.1
Calipers
Calipers follow a progression which
originates with standard inside and outside
calipers and are non-graduated tools for
measuring the distance between two points of
contact on the work piece. This distance then
must be transferred to an actual dimension by
use of a graduated direct measuring instrument.
—
a.
Standard Calipers consist of two movable
metal legs attached together by a spring
joint at one end and with formed contacts at
the other, and so designed as to take inside
readings (contacts facing in), or readings
from one point to another and these are
called inside calipers, outside calipers, and
dividers, respectively. Accuracy obtained
with these tools depends largely on the
inherent skill of the user. Care in removing
the caliper from the work piece without
disturbing the setting shall be observed.
Finally, the measurement shall be carefully
—
6.5
Straight edges
are flat length of tools or
stainless steel, ground to extremely fine
tolerance, particularly along the edges. They are
used for scribing accurate, straight lines and to
check surfaces for straightness.
—
Section 7.0 Special-Purpose Measuring
Tools
Among the many measuring tools designed for
specialized applications are:
243
CHAPTER 12- METROLOGY
7.1
7.2
directed into the part to be tested to determine
the metal thickness precisely.
Tap and Drill Gages consist of a flat rectangle
of steel with holes accurately drilled and
identified according to their size. These cover
letter size, number size, fractional size and
National Fine and Coarse Thread Series.
—
8.6
are round steel plates with slots
Wire Gages
of ascending width along their edge. Each hole
is numbered according to its size in terms of
various standard gages. In the tap and drill
Gage and wire Gage, the drill, tap, or wire is
placed through the hole or in the slot and the
smallest hole or slot which will accommodate the
piece denotes the size of the measured item.
—
7.3
consist of a metal case
Screw Pitch Gages
containing many separate leaves. Each leaf has
teeth corresponding to a definite pitch. By
matching the teeth with the thread on work, the
correct pitch can be read directly from the leaf.
7.4
Radius Gages are individual leaves or a set of
leaves in a case and are designed to check both
convex and concave radii.
7.5
ThicknesslFeeler Gage consists of a number
of thin blades/leaves of different thickness and
used in checking clearances, backlash in gears
and for gaging in narrow points or places.
Eddy Current Testing. This method is useful
for flaw detection, sorting by metallurgical
properties such as hardness and thickness
measurement. The changes of magnitude and
phase difference can be used to sort parts
other
and
temper,
according to alloy,
metallurgical properties.
Section 9.0 Pressure and Vacuum
Measurements
In industrial applications pressure is normally
measured by means of indicating gages or recorders
and are classified as mechanical, electro-mechanical,
electrical or electronic types. Mechanical instruments
maybe further classified as:
—
9.1
—
—
Pressure measurement by balancing an
unknown pressure against a known force is the
will
that
method
oldest
and
simplest
being
pressure
static
the
automatically balance
measured against a resisting force whose
magnitude can be read directly from the
instrument or can be easily computed.
a.
Liquid-Column Gages The liquid-column
pressure gage used mostly in industry is
some type or either U-type or well-type of
manometer. The U-type is made of glass or
some other type of transparent tubing with
an inner bore of 6 mm or larger diameter
and a wall thickness adequate to withstand
the pressure for which the manometer was
in designed. The well-type is similar to the
U-type, however, one leg of the U-type is
replaced by a well. The inclined manometer
or draft gage is a well manometer whose
vertical leg is placed in an almost horizontal
position so that a very slight difference of
change in the pressure of the gas or air in
the well causes a very large change in the
measured level of the liquid in the inclined
tube. The barometer, a special type of well
manometer is an upright measuring tube
which is vacuum and sealed on the upright
end and the open end in inserted in a well
filled with liquid mercury.
b.
are used for
Limp-Diaphragm Gages
houses
boiler
measuring low pressure in
low
where
implications
other
and on
measured.
accurately
must
be
pressures
They are also designed for measuring draft
pressure of combustion gases.
Section 8.0 Non-Destructive Inspection
81
Hardness Measurement. In determining the
hardness of mild steel and non-ferrous alloys, a
penetration hardness tester is utilized and
mostly semi-portable.
8.2
Magnetic Particle Inspections. In this type of
material
and
voids,
cracks,
inspection,
discontinuities can be detected through the
setting up to intense magnetic field in the parts
to be inspected. This method is used to indicate
surface imperfections in any material that can be
magnetized.
8.3
is
This
Inspection.
Radiographic
accomplished by exposing a part to either X
rays, gamma rays, or radioisotopes and viewing
the image created by the radiation on a
fluoroscope or film.
8.4
Fluorescent Penetrants. These are used to
find surface defects in almost any material.
8.5
Ultrasonic Testing. In ultrasonic testing a high
frequency vibration or supra-audible signal is
—
/
244
—
CHAPTER 12- METROLOGY
9.2
c.
Bell-type Gages
designed for measuring
low pressure. This type of Gage utilizes the
large area of a liquid- sealed bell chamber to
provide the force necessary to actuate an
indicating or recording mechanism and can
be made sensitive to the smallest change of
pressure likely to be significant in an
industrial application, and yet be rugged
enough
endure
to
considerable
mistreatment.
d.
Piston Gajes suitable for pressure up to
350 kg/cm and higher but limited largely to
hydraulic applications where oil is the fluid
under pressure. The Bailey power-operated
dead-weight piston Gage is designed for use
as a master pressure Gage in powerhouse
service where a power-operated, sensitive
Gage with a highly suppressed scale is
desirable.
transmit the live steam pressure to the gage,
thus preventing gage error and damage
caused by the elevated temperature of live
steam. !n applications involving rapid
fluctuations or pulsations in pressure, gage
snubbers shall be used to throttle the
pulsations without seriously obstructing the
passage to the gage. Care shall be taken so
that the throttling orifice is not too small
because, if the liquid or gas contains dirt or
foreign materials, the orifice may clog and
block the line to the gage. Pressure gages
shall not be mounted on equipment
subjected to excessive vibration. External
vibrations cause excessive wear and
inaccuracies in gage indications. Wherever
possible, use only gages least effected by
vibration. All pressure gages installed on
steam boilers shall have a dial range of less
than one and one-half (1 %) times and not
more than twice the maximum allowable
working pressure and the face of the Gage
shall not be less than 75 mm.
—
—
Pressure measurement by deformation of an
elastic membrane is the most universally used
for measuring high and medium-pressure
because of its simplicity, compactness and
maintenance-free property. It is also widely used
in the field of low-pressure measurement where
a large actuating force is not needed.
a.
Bourdon tube gage is the most widely used
industrial pressure Gage applied to both
pressure and vacuum, either separately or in
a compound Gage. It is usually used
whenever the maximum of the required
range exceeds 1.7 kg/cm
2 for measuring
combined pressure and vacuums, for
continuous
pressure
measurements
exceeding 5.6 kg/cm
2 and up to 3500 kg/cm
2
or more direct pressure measurements, and
especially
where
sudden
pressure
fluctuations occur which could cause below
or normal diaphragm to rupture. Bourdon
tubes may be made of any type of materials
that has the proper elastic characteristics
suitable for the pressure range and the
corrosive resistance of the media to be
measured in the application. When bourdon
tube gages are used with corrosive chemical
liquids of liquids that solidity at normal room
temperature diaphragm shall be placed in
the line and the gage line filled with water or
oil and sealed. The sealed system then
senses the diaphragm movement and
indicate the pressure. When these gages
are used to measure steam pressure, a loop
shall be placed in the gage line so that the
liquid condensate is trapped and used to
b.
Helical Type of Pressure Gage variations
of the simple Bourdon type of pressure gage
wherein the element or tube is wound in the
form of a spiral having four or five turns. This
increases the travel of the tip considerably
and forms a compact unit easily constructed
and installed in a pressure gage.
c.
Spiral type of element in bourdon type of
Pressure Gage
the elements is of
Bourdon type of tube wherein it is wound in
the form of a spiral having several turns
rather than restricting the length of the tube
to approximately 270° of arc. This
arrangement in no way alters the theory of
the Bourdon tube but simply has the effect
of producing a tip movement equivalent to
the summation of the individual movements
that would result from each segment of the
spiral considered as a Bourdon tube.
Although this construction is more difficult
and expensive to build, it has such an
advantage for recording pressure gages that
it is almost universally used for all low-and
medium-pressure records. The helical type
and the spiral type of elements are widely
used for recording thermometers.
—
—
d.
245
Metallic-diaphragm Pressure Gage
consists of a metal diaphragm built into
diaphragm housing with one side of the
diaphragm exposed to the pressure to be
measured and the other under atmospheric
—
CHAPTER 12- METROLOGY
scale reading. The standard tilt high
precision McLeod gage has been modified
to simplify its operations, use less mercury,
be more rugged and compact, and still retain
its precision. The newer modified gage is
known as the adjustable closed and
improved McLeod gage.
pressure. The pressure transmitted to the
Gage dial by means of a linkage connected
to the center of the diaphragm.
e.
f.
has a large
Sector Gear Arrangement
sector gear mounted at right angles to a link
connecting the sector gear arm and the
bourdon tube tip movement. A small pinion
gear, to which the pointer is attached, is
then matched to the sector gear. The sector
gear and the pinion gear are commonly
made of bronze and may be machined,
broached, or stamped, depending on the
quality and accuracy required of the gage.
-
Pirani Gage. The Pirani Gage is a hot wire
vacuum gage. This gage employs a
wheatsone bridge circuit to balance the
resistance of a tungsten filament or resistor
sealed off in a high vacuum against that or a
tungsten filament which can lose heat by
conduction to the gas whose pressure is
being measured. In this circuit the zero drifts
caused by slight deviations of the bridge
voltage are compensated for the resistor
sealed in the high vacuum. A change in the
filament temperature. This causes a change
in the filament resistance and unbalances
the bridge. The bridge unbalance is then
3 as the dry air pressure, by
read across R
means of a micrometer, calibrated in
pressure units. The useful range for the
Pirani gage is from 1mm to 100 mmHg. The
Pirani gage has the advantage of being
compact, simple to operate, and can be
opened to the atmosphere without burnout
failure. The main disadvantage is that the
calibration depends on the type of gas in
which the pressure is being measured.
These gages are useful for pressure
measurements involving acetylene, air,
argon, carbon dioxide, helium,, hydrogen,
and water vapour for the general pressure
range of 1 to 200pm (1mm = 1 x 10 meter
mm) and is most
which is equal to 1 x
useful and accurate in the 20 to 200 pm
range.
c.
The
Knudsen Type Vacuum Gage.
Knudsen Gage operates on the principle of
heated gases rebounding from a heated
surface and bombarding a cooled movable
surface (vane) spaced less than a mean free
path length from the heated surface. The
gas particles rebound from the cool vane
with less energy than from the heated vane
which tends to rotate the cool vane away
from the heated vane within the restriction of
a suspension system designed to carry a
galvanometer mirror for producing a reading
on a fixed scale. The particular advantage of
the Knudsen Gage operating principle is that
the Gage response is relatively independent
of the composition of the gas whose
Cam and Roller Arrangement employs a
cam sector and a Helicoid roller to which a
pointer is attached. The Helicoid stainless
steel roller is long wearing and used
especially in services on engines, turbines,
blower, hydraulic presses, pumps, and
pressure
violent
where
compressors
pulsations or severe mechanical vibrations
occur.
—
9.3
Electromechanical pressure instruments usually
employ a mechanical means for detecting the
pressure, and an electrical means for indicating
or recording the detected pressure. They are
combinations of mechanical bellows, metallic
diaphragms, or bourdon tubes with electrical
sensing, indicating, recording, or transmitting
transducers,
pressure
employing
devices
oscillating
and
transducers,
inductive
transducers.
9.4
Electronic pressure measuring instruments
normally depend on some physical change that
can be detected and indicated or recorded
electronically.
9.5
Vacuum Gages-Mechanical, Electrical and
Electronic. The pressure gages used primarily
for measuring pressure below atmospheric
pressure, which is most often referred to as
vacuum, are McLeod gages, Pirani gages,
Knudsen gages, thermocouple gages, Phillips
gages, and ionization gages. The different types,
except for the Knudsen Gage.
a.
b.
McLeod Gage. The McLeod Gage is a
mercury Gage for the measurement of
absolute pressure. It is one of the most
basic type and has a measurement range
from 2 pm to mmHg. There are three types
of McLeod gages. The swivel McLeod gage
has an accuracy of 3% of reading or mm of
246
CHAPTER 12- METROLOGY
pressure is being measured. In spite of this
very desirable feature, the Gage is not
widely used because the torsion system is
rather delicate and sudden inrushes of air
cannot be tolerated. New developments are
being investigated that may make the Gage
more acceptable for industrial applications
d.
relatively good accuracy. The disadvantages
of these gages is that the filament can burn
out quickly if it is heated before the pressure
is at low enough vacuum, and to have an
automatic cut out to protect the ionization
tube in case of a system leak or break.
The Alphatron Gage (National Research
Corporation) uses a radium source
sealed in a vacuum chamber where it is
in equilibrium with its immediate decay
products. This provides a constant
source of alpha particles for ionizing the
gas particles present in the vacuum
chamber. The alpha particles collide
with the gas molecules in the same
manner as the electrons in the hot
filament tube just discussed. The
advantages of this Gage are the same
as those of the hot Gage, but it
overcomes the burnout problem, the
fragility, and the emission instability.
Some of the disadvantages are that at
very low pressure a preamplifier is
required to give an undistorted output
and the current produced are in order of
10h1
1013 and
to
are directly
proportional to the numbers of ions
collected on the grid in a given time.
With proper circuitry the response of the
gas, within its range, and the indicator or
recorder can be made linear with
respect to the pressure, regardless of
the
nature
of
the
gas
under
measurement.
Phillips Vacuum Gage Phillips gages are
cold cathode ionization gages which provide
direct measurement for pressure values
both above and below 1pm. These gages
cover the 0.05 to i0 mmHg pressure
range. The schematic shows the basic Gage
circuit. The pressure measurement is a
function of the current produced by a high
voltage discharge. The electrons drawn from
the cold cathode are caused to spiral as
they move across a magnetic field to the
anode. This spiral motion greatly increases
the possibility of collisions with the gas
molecules between the cathode and anode,
and produces a higher sensitivity by creating
a higher ionization current. The output is
read out on a micrometer calibrated directly
in pressure units. The range is divided into
four separate outputs with direct reading for
each portion of the total range. The
advantages of this Gage are the wide range
that it can cover, absence of filaments to
burn out, rugged metal construction, and
ease of cleaning and maintenance. The
disadvantages are that cold cathode tubes
are slower to outgas than hot filament tubes,
they are adversely affected by mercury, and
there is a higher breakdown of organic
vapors at higher voltages. These factors
limit the use of these gages, to applications
in which oil diffusion pumps are used.
—
All electrical and electronic vacuum
gages now employ the latest solid state
circuitry to maintain the constant
àurrents and voltages. This type of
circuitry had added to both the stability
and accuracy of measurements.
The ionization tube is primary detector and
is constructed of glass. It contains an anode,
a grid, and a filament are attracted to the
grid, pass through the grid, and form ions by
collision with the molecules present between
the grid and the anode. The positive ions are
collected on the anode, and the electrons
are collected on the grid. The positive ion
current created is proportional to the amount
of gas present, if the electron current is kept
constant rate by means of a grid current
regulator. The advantage of this type of
Gage is that very low pressures can be
detected and measured in vacuum furnace
and mass spectrometer applications. The
ionization Gage can be used in the 1 micron
to 2 x 10:11 mmHg pressure range with
e.
247
Vacuum Gage Calibration. The majority of
industrial vacuum application do not require
ultimate
the
vacuum
in
calibration
techniques. To calibrate the most industrial
vacuum
and
gages
equipment,
a
comparison gage that covers the calibration
points from the one im to i0’ mmHg range
is sufficient. A precision McLeod gage can
be used as the standard. The calibration
points plotted for the vacuum gage is being
calibrated as the manifold system is
evacuated. Care must be exercised to
ensure that a sufficient low pressure is
reached with hot filament vacuum gages to
CHAPTER 12- METROLOGY
a.
prevent filament burn out. Care must also be
taken to guarantee that filament gages are
properly outgassed during the calibration
procedure.
Where calibration are needed for very high
vacuum technique measuring gages, a
calibrated precision ionization gage should
be used as the standard. This type of Gage
has a range down to pressure of 1013 torr.
This type of calibration equipment is
expensive and finds applications in the
industrial laboratory rather than in process
or manufacturing systems. There are some
exceptions such as mass spectrometer
application for isotopes, and used in special
electron welding chambers.
Thermocouple pyrometers in which the
voltage, generated at the junction of two
dissimilar metal wire indicates the degree of
temperature, the voltage at the junction
the
with
proportionally
increasing
temperature.
1.
(a) Thermocouple wires shall be
chosen in such a way that they
produce a large electromotive
force that varies linearly with
temperature,
and
(b) they shall be corrosion
the
in
oxidation-resistant
atmosphere and temperature
range where they shall be used,
—
Section 10.0 Thermometry and Pyrometry
10.1
Indicating and Recording Thermometer
pressure-actuated instrument that uses the
energy available in the form of increased
pressure or volume a substance to indicate and
record the change in temperature that liberated
this energy.
(c) they shall be resistant to change
in characteristics that shall
affect their calibration,
—
(d) they shall be free from parasitic
currents,
10.2 Proper location of an indicating and recording
thermometer
(e) required readings shall be
reproducible within the accuracy
limits,
—
a.
b.
c.
The thermometer bulb shall be located in
such a way as to permit the recorder to be
removed for repair.
2.
The thermometer tubing shall be properly
fastened and out of the way of damage from
operators, mechanics, and pipe fitters who
may have occasion to work near the
installation.
The angle of the tube at the neck of the bulb
shall be protected.
e.
The tubing shall never be in contact with hot
steam pipes or stacks which would increase
the chance of ambient-temperature errors.
f.
(f) they shall be physically strong
high
to withstand
enough
temperature, rapid temperature
changes.
The recorder shall have enough tubing to
permit the bulb to reach a convenient
location for the test bath.
d.
of
Temperature limitations in the
selection of thermocouple materials
(a) Copper-Constantan
commonly used in the 185 to
300°C temperature range and
superior for measurement of
low temperatures,
relatively
temperatures
subzero
especially
and stand up well against
corrosion and are reproducible
to a high degree of precision.
used in
(b) Iron-Constantan
reducing atmosphere where
there is a lack of free oxygen
and useful in the -18 to 760°C
the rate of oxidation increases
rapidly, and so heavier wire
shall be used for 540°C
protection
and
applications,
-
—
of bimetallic recording
location
The
thermometers shall be carefully checked for
dirt and dust in the air.
Types
10.3
Instruments:
Specifications in the selection of
thermocouple materials:
Temperature-measuring
248
CHAPTER 12- METROLOGY
wells shall be used to cover the
thermocouple. Unprotected iron
constantan thermocouples shall
only be used up to 35°C in
reducing atmosphere.
(e) Where is danger of a couple
fusing
from
the
high
temperature, it shall be partially
immersed on order to keep it
cool.
(c) Chromel-Alumel
shall be
used extensively in oxidizing
atmospheres where there is an
excess of free oxygen and shall
be
used
to
measure
temperature up to 1320°C, but
are
most
satisfactory
at
temperatures up to 1150°C for
constant
service.
Reducing
atmospheres have a tendency
to change the thermoelectric
characteristics
of
these
materials and reduce their
accuracy.
(f)
—
(g) The couple shall be installed in
a pocket to prevent damage
from material in the furnace.
(h) If a porcelain protecting tube is
used, care shall be taken to
bring
the
furnace
to
up
temperature slowly in order to
prevent cracking the tube. A
porcelain tube shall never be
inserted in a hot furnace.
(d) Platinum-Plantinum-Rhodium
normally designated noble
metal thermocouples, shall be
used for higher temperatures
range (700 to 1500°C) and are
adversely
affected
by
atmospheres
containing
reducing gases and shall be
protected by an impervious tube
when used at temperatures
above 540°C when such gases
are present.
—
3.
Proper
installation
Thermocouples
If the thermocouple is mounted
horizontally and the temperature
is above the softening point of
the tube, a support shall be
provided to prevent sagging.
4.
Important
considerations
wiring a thermocouple:
in
(a) Conduct shall be used and
thermocouple head shall be
connected directly with a flexible
cable to protect the binding-post
connections
between
the
thermocouple and the lead
lines.
of
(b) All wires that must be spliced
shall be soldered.
(a) The thermocouple shall not be
located in the direct path of a
flame.
(c) No less than 3.31 mm
2 copper
wire shall be used with the
millivoitmeter pyrometer in order
to reduce the resistance of the
circuit to a minimum.
(b) It shall be located where the
average
temperature
is
measured. For a large furnace,
it shall be desirable to install
several couples in different parts
of the furnace.
(c) It shall be located where the hot
end can be seen from a door of
the furnace.
(d) Wires shall never run parallel to
or cross within 30 centimeter
any a.c. line of 110 volts or more.
(e) Surge Lightning arresters shall be
used where there is danger from the
source.
(d) The couple shall be immersed in
the furnace or vessel far enough
so that the junction is entirely in
the
temperature
to
be
measured.
(f)
249
Rotary switches used for connecting
the thermocouples to the indicating
instrument shall be very rugged to
CHAPTER 12- METROLOGY
temperature
withstand the
measured.
b.
to
(e) Thermistors shall be used within the
80 to 400°C temperature range
be
-
Resistance thermometers in which the
resistance of a calibrated wire changes with
the temperature, the resistance change
being proportional to the increase in
tern perature.
1.
c
and
Thermometers
Resistance
resistance
A
Thermistors
thermometer is basically an instrument
for measuring electrical resistance,
which has been calibrated to read in
degrees of temperature instead of units
of resistance. Industrial resistance
thermometers have been historically
been made of platinum, copper, or
nickel but, with advances made in the
have been
semiconductor materials
found suitable for the thermistor is one
type. Thermistors which are thermally
electronic
are
resistors
sensitive
electrical
whose
semiconductors
resistance varies with temperature and
are useful industrially for the automatic
detection, measurement, and control of
physical energy.
—
2.
Liquid-filled glass thermometers in which
there is an expansion or contraction of a
liquid corresponding to the changes in
temperature, the expansion of the liquid
being proportional to the increase in
temperature, the liquids commonly used of
which are mercury, alcohol, or pentane.
Requirements for Liquid-filled
Thermometer Liquids
1.
(a) The vapor pressure shall be
negligible over the temperature
range for which it is to be used.
(b) The coefficient of cubical
expansion shall be high.
(c) The liquid shall be chemically
inactive with respect to the metal
in the thermometer system.
(d) The liquid shall have a low
specific gravity, a low specific
heat, and a high coefficient of heat
conductivity.
Characteristics of Resistance
Thermometers/Thermistors
(e) The iquid shall be incompressible.
(a) Frames where coils of wire are
wound shall be insulated by
materials capable of withstanding
the temperatures for which the
thermometer is designed.
Industrial liqud-fiIied tnermometers are used for
measuring the temperature of molten metal in
monotype casting machines, flue gas, ovens,
kilns, air in air ducts, dough testing, cruller
frying, hard candy, cream cooking. chocolate
melting, and mixing, refrigerators and cooling
units, hot and cold water, steam, cooking
vessels, brewing vats, lubricating oils, air
compressors, and diesel engines, and for other
applications in which the temperature sensitive
bulbs can kept completely and constantly
submerged in the medium at the point of
maximum circulation.
(b) To obtain the highest sensitivity of
measurement the material shall
have the greatest resistance change
per degree for a given value of
resistance, but it shall have good
stability over a long period of time
and over a wide range of
temperatures without changing its
electrical characteristics.
2.
(c) Metals to be used shall have a
higher degree of linearity over the
resistance-temperature range for
which the thermometer is designed.
Requirements to obtain the best
accuracy with industrial liquid
filled thermometers.
be
shall
thermometer
(a) The
installed properly so that the
temperature sensitive bulb can
reach temperature equilibrium
with the surrounding medium.
(d) Resistance thermometers shall be
used within the 40 to 50000
temperature range.
—
250
CHAPTER 12- METROLOGY
(b) The temperature sensitive bulb
shall also be properly immersed in
the medium to be measured to
eliminate the immersion error.
1.
When temperature must be measured
and physical contact with the medium to
measured
be
is
impossible
or
impractical, thermal radiation or optical
pyrometry methods and equipment are
used. Industrial applications requiring
radiation
thermal
pyrometers
for
measurement and control may employ
infrated techniques, so called total
radiation methods, or the two-color
method.
2.
Radiation
pyrometers
are
used
industrially where temperatures are
above the practical operating range of
thermocouples, where thermocouples
life is short because of corrosive
atmospheres, where the object whose
temperature is to be measured is
moving. Inside vacuum or pressure
furnaces, where temperature of a large
surface when it is impractical to attach
primary temperature sensors.
(c) The
thermometer
shall
be
installed at the point of maximum
flow to provide the most rapid heat
transfer from the medium under
measurement to the bulb.
Bourdon tube thermometers which operate by
the expansion of a fluid (liquid or gas) as
follows
d
—
1.
2.
3.
expansion of liquid that completely fills the
enclosed tubing and bulb of the
instrument,
expansions of the liquid in the bulb
of
the instrument,
expansion of a gas that completely fills the
tubing and bulb of the instrument.
a.
Classification of Bourdon Tube
Thermometers
f.
—
Bourdon Tube Thermometers are
classified according to the kind of
fluid with which they are filled. Class
I are those of the liquid-filled kind,
the liquid filling completely the bulb,
capillary tube, and the spring that
actuates the indicating mechanism
of the thermometer and liquid
expansion is the actuating medium.
Class 2 are only partly filled with
liquid, most of which is in the bulb
and the vapor of the liquid fills the
capillary tube and the spring of the
indicating
device
vapor
and
pressure is the actuating medium.
Class 3 is filled completely with gas.
The liquid-filled kind and the gasfilled kind depend for their operation
on the expansion of liquid and gas,
respectively. The vapor-pressure
kind is operated by the pressure
inside the spring of the indicating
mechanism; this pressure depends
entirely on the temperature of the
free surface of the liquid in the bulb.
e.
Optical
Pyrometers
which
by
temperature is determined by matching
luminosity of the hot body of which
temperature is to be determined with
luminosity of a calibrated source of light.
the
the
the
the
1.
Instrument
that
measures
the
temperature of a heated body not by
means of a color-temperature relation
but by means of a color-temperature
relation but by means of the light
intensity relation for a particular portion
of the visible spectrum. This is the
device officially recognized internally for
measuring temperature above 570°C.
2.
Advantages of an optical pyrometer
(a) No direct contact with the object
whose temperature is to be
measured is required other than it
be in view.
(b) The instrument can be used to
measure temperature as high as
2760°C (mostly used within the
1650 to 2760°C temperature range).
(c) The temperature measurements are
practically independent of the
distance of the operator from the
heated body.
Radiation pyrometers in which there is a
small body capable of absorbing radiation of
all wave lengths, the radiation absorbed
being proportional to the temperature.
251
CHAPTER 12- METROLOGY
The phenomenon usually measured is either
pressure differential or velocity in the pipe.
(d) The measurements can be made
with great rapidity, and temperature
gradients easily determine along
any visible part of a heated object.
1.
a.
b.
b.
c.
g. Pyrometer cones by which the temperature is
determined by the bending over of a graded set of
ceramic cones, each having a definite heat
resisting value.
h.
2.
Bimetallic thermometers depend on the differential
expansion of two solids, the differential expansion
being proportional to the increase in temperature.
1.
Venturi-tube type
Flow-nozzle type
Orifice-plate type
Pitot-tube type
Area meterslRotameters
A rotameter consists of a tapered glass
tube set vertically in the fluid or gaseous
piping system with its large and a top
and a metering float which is free to
move vertically in the tapered glass
tube. The floe through a rotameter is
based ona variable orifice with a
the
differential,
constant-pressure
indication of flow being obtained from
the measurements of the orifice
obtained by noting the position of the
float on the tapered tube.
Constructed of two thin strips of dissimilar
metal which are bonded together for their
entire length. In industrial thermometers, these
bonded strips are often into a helical coil,
wherein one end of the coil is welded to the
thermometer stem, and the other end to the
pointer staff. Bimetallic thermometers are not
recommended for use at temperatures above
425CC on continuous duty or above 54OC in
intermitted duty. Materials most used in
bimetallic thermometers are in bar, which is an
alloy of nickel and iron, as the low expansion
metal, and brass or nickel-chrome alloy as the
high expansion metal. Temperature wells can
be used with bimetallic thermometers as
protective devices against wear and corrosion.
These thermometers maybe used in refineries,
oil burners, tire vulcanizers, hot solder tanks,
coffee urns, hot water heaters, tempering
tanks, electric dipping tanks, diesel exhaust,
and impregnating tanks. Calibration of these
thermometers can be made by a comparison
method using heat sinks, water baths, or
adequate
where
furnaces
calibrating
immersion space is available.
3.
AnemometersAnemometers are instruments for
measuring the flow of gas or air consists
of a set rotating vanes placed at an
angle of about 45 degrees to the axis
flow and free to rotate about an axis set
in jewelled bearings. The rotating shaft
in turn operates a counting mechanism
which registers the number of revolution
of the vanes. The velocity of the air flow
is obtained by timing the rotaion of the
vanes for a certain definite period and
noting the number of revolutions mde
In determining the
during this time.
it is necessary to
flow,
quantities of air
determine not only the velocity but also
the readings of pressure, temperature,
and pipe area. The deflecting-vane type
of anemometers indicates air velocity
directky on a dial without timing and far
sensitive to low-velocity flows.
Electronic thermometers the latest breakthrough
in the measurements of temperature with very
high accuracies, fast speed of response and
above average linearity.
—
Section 110 Flow Metering
11.1
The differential-pressure meters-
Classification on flow meters
4.
A. Inferential type
Electrical meters1.
The inferential type of meters obtains a
measurement of the flow of a fluid or gas not
by measuring the volume or weight of the
medium but by measuring some other
phenomenon that is a function of the
quantity of fluid passing through the pipe.
252
Conductance
Air
Electrical
Meters. By utilizing the ability of
gas to conduct heat from a wire or
grid heated electrically it is possible
to obtain a quantitive measurement
of a gas flowing through a pipeline
or air duct. Since the ability of a gas
CHAPTER 12- METROLOGY
to conduct heat will vary with the
velocity, this fact can be used to
determine the rate and quantity of
flow through the pipe. Two methods
are use to determine flow by
conductance
the
hot wire
anemometers which consists of a
small resistance wire inserted in the
steam of gas whose velocity is to be
measured, and the Thomas meter
which consists of wire grid inserted
in the pipe line or duct and supplied
with
current
a
of
sufficient
magnitude to heat the air passirig
through the pipe.
type, which means that a piston or
plungers delivers a fixed volume on
each stroke used to deliver controlled
volumes at a very high pressure.
a.
—
Nutating-Disc Pump
positive
displacement flowmeter wherin the
piston is the only moving part on the
measuring chamber. The action of
the piston resembles the action of
the top when it has passed its peak
speed and starts to wobble or nutate
just before it loses speed and goes
out of control. The motion of the
disc piston is controlled by the shaft
-
Table 12.5
Classification of Temperature Measuring Instrument
—
Type of Thermometer
Liquid-in-glass
Temperature
Accuracy
-62 to 510
Liquid-in-metal
1.75 kg/cm
39 to 652
Medium
Slow
Vacuum to 350 kg/cm
40 to 325
Medium
Medium
Atmospheric
87 to 540
Medium to high
Fast
Atmospheric
-40 to 540
Low to medium
Medium to slow
7 kg/cm
High
Medium to fast
Vacuum to 25 kg/cm
-
Gas actuated
-
Bi-metal
RTD
Pressure Range
Medium
-
Vapor actuated
Speed of Response
Medium to high
-
73 to 540
Thermestor
118 to 400
Medium to high
Fast
Vacuum to 25 kg/cm
Electronic
18 to 175
High
Fast
Vacuum to 25 kg/cm
2.
Electromagnetic
Flowmeter
Electrical primary detectors of the
rate of flow.
In this type of
flowmeter, an electromotive force is
induced in the fluid by its motion
through a magnetic field provided by
the electiomagnet.
The dc
magnetic field acts vertically through
the pipe that carries the fluid. The
electromagnetic
flowmeter
is
valuable in measuring the flow of
liquid metals,
corrosive fluids,
slurries and other conductive fluids
and it is not affected by viscosity,
density, or turbulence.
B. Volumetric and Current types
1.
as it moves around the tapered can, this
can keeps the lower face of the piston in
contact with the bottom of the
measuring chamber on one side of the
pump; and keeps the upper face of the
piston in contact with the top of the
measur”i chamber on the opposite.
The pist3n is positioned so that the
lower side of the disc is in contact with
the bottom of the measuring chamber
on the left hand side, while the upper
side of the disc is in contact with the top
of the measuring chamber on the right
This method of pumping
and side.
produces a smooth and continuous flow
no
with
pulsation
of
separate
compartment of the measuring chamber
is successively filled and emptied. The
measuring chamber is sealed off into
separate holds with a definite volume.
Nutating piston meters are designed for
the rate of flow of the liquid to be
—
-
Piston-Type Volumetric Flow Meter
used to inject an exact amount of fluid
into flow line or a collecting vessel. The
piston pump is generally a reciprocating
—
253
CHAPTER 12
and
for
measured
pressures. Selection of a
based on the flow rate,
and allowable pressure
intended application.
b.
-
METROLOGY
The flow of the liquid around the cylinder
is restricted by four small semi-circular
buckets built into flutes in the cylinder
surFace and free to rotate about center
pivots fastened to the meter body, so
that they rotate about their own pivots
simultaneously with the rotation of the
cylinder upon which they are mounted.
The outer edge of the buckets makes a
close fit with the meter body and seals
the meter at all times from any liquid by
pass. As a result of the rotation of the
cylinder and buckets, the liquid trapped
in the buckets or between the buckets
and is therefore metered volumetrically,
and the number of revolutions of the
rotating cylinder is directly proportional
to the flow.
line
nominal
meter shall be
line pressure,
drop for the
Rotary Sliding-Vane Flowmeter
volumetric meter constructed similarly to
the standard vane type of vacuum
pump, wherein the design requires that
the meter body be in the shape of a
closed drum with shaft carrying a
smaller cylinder arranged to rotate
inside the meter body. This shaft is
mounted eccentrically with respect to
the center of the meter chamber, and
the cylinder is slotted to permit the one
or more vanes to project from the
cylinder to the wall of the meter body.
The rotation of the vanes carries the
liquid across the meter and forces it out
on the opposite side because of the
reduction in volume caused by the
eccentric position of the drum with
respect to the meter body. A counter on
the rotating shaft gives a direct
indication of the total flow of liquid
through the meter. This type of meter
works successfully on the liquid that is
not abrasive or dirty. Dirty liquids are
very destructive because of the
comparatively high rotative speeds and
the large areas subject to wear.
—
c.
Oscillating-Piston Flowmeter—consists
of the hollow piston arranged to oscillate
about the center abutment which is
encircled by a confining ring housed in a
drum-shaped meter body. Capacity of
this type of flowmeter ranges fro 8gpm
to 7,000gpm, and the error due to
density or viscosity variation is small.
As the rotating parts are close fit, the
liquid measured must be clean and free
from abrasive materials.
d.
a
Flowmeter
Rotating-Bucket
positive-dislpacement of a volumetric
meter consisting of a meter with a drum
type of body having the outlet and inlets
ports side by side with a dividing baffle
between them. A center cylinder is
suspended concentrically inside the
meter body with a close clearance on
the sid3es of the meter chamber and the
diameter approximatelya quarter smaller
than the diameter of the meter body.
e.
Screw Type of Flowmeter consist of
three meshed screws or rotors mounted
vertically and rotating in a measuring
chamber. The center, or power, screw
is approximately twice as large in
diameter as the two idler rotors and has
a large thread of special shape
designed to seal the meter completely
by meshing with the idler rotors and
provide maximum meter capacity. The
metering chamber is shaped to seal the
outer edge of the three screws against
any possible by pass of the liquid. The
screws are located in a straight line, and
hence the chamber cross section is that
of a large circle with diametrically
opposite smaller segmented section cut
in the large chamber to seal the two
other idler screws. The head pressure
of the meter forces the liquid in at the
bottom of the screws where it caused
the latter to rotate and in so doing is
carried up through the measuring
chamber and out at the top of the meter.
The meter counter or register is driven
off by the large power rotor through a
gear train which is oil enclosed to
prevent contact with the liquid in the
meter. This type of flowmeter is used in
liquid with low viscosity; otherwise the
pressure drop across the meter may be
excessive.
f.
consists of
Spiral-Vane Flowmeter
metering chamber in which a rotor is
mounted with a hallow shaft which
admits the liquid into a meter. The rotor
is similar in design to that of a
—
254
—
—
CHAPTER 12
-
METROLOGY
centrifugal air blower with curved blades
mounted between disc attached to the
rotating shaft. As the liquid flows into
the buckets formed by the spiral blades
of the rotor, a rotating action takes place
something like that which occurs in a
simple water wheel. If the flow is not
great enough to fill the meter and in this
way flood the spiral vanes, then the
rotation of the rotor is a direct indication
of the quantity of fluid flowing, and a
counter, or register, on the rotor shaft
will give the total flow.
g.
h.
Bellows-Type Gas
Flowmeter
designed primarily and exclusively for
gas-receiving bellows having metal
slides and tanned sheepskin flexible
connections between the metal slides.
These two bellows are mounted
vertically in a tin or steel case and
connected through pipes to two slide
valves mounted on a vertical plate
above the bellows and inside the steel
case. The gas flows from the inlet pipe
alternately into one or the other of the
two bellows. It is in then exhausted into
the outer chamber and then passes out
of the meter through an outlet pipe
connected to the gas chamber.
A
counter or register of a typical gas-meter
type is also driven from the crank or
gear mechanism.
Adjustments are
usually provided for the stroke of the
bellows and for the timing of the valves
to aid in calibrating the meter.
give a true indication of the volume of
gas discharged.
Roots Type of Volumetric Gas Meter
consist of a set of two rotors having a
cross —sectional area (at right angles to
the rotating shaft) in the approximately
shape of a figure eight. The rotors are
so mounted in the right meter body so
as to mesh at right angles to each other
by means of two gears mounted outside
the meter body on extensions of the
rotor shafts. The gas is admitted at the
top of the meter, and the head pressure
causes the rotors to revolve.
In so
doing they trap a certain of gas between
the rotors and the meter body. The gas
is prevented from by-passing the meter
between the rotors by the close mesh of
the rotors, which almost but not quite
touch at all times. As a result, this
meter is a true volumetric meter, and the
revolutions of either shaft are a direct
indication of the flow.
—
—
Water-Sealed Rotary Gas Meter
consists of a drum-shaped meter body
slightly more than half full of water. A
rotor with spirally shaped vanes very
similar to those used in the center of the
rotor shaft and below the level of the
water which is maintained somewhat
above the shaft.
It then discharges
through a short vertical pipe just above
the water level, after which it is trapped
in the chamber formed by the spiral
vane which has both ends submerged
under the water; the pressure of the gas
causes the rotor to revolve. When one
vane emerges from the water and
releases the pressure, the next vane
form a closed chamber and continues to
cause the rotor to revolve. If the water
level is exactly correct, there will be no
by-pass, and the rotation of the rotor will
—
255
j.
Turbine-Type Current Flowmeters
used for measuring flows ranging from
0.003 to 15000 gal/mm as standard
liquid flowmeters, and 20 to 9000 cu.
ft/mm as gas flowmeters. Standard and
pipeline meters flows are dependent on
the viscosity of the liquid being
measured, and gas meters on the
density of the gas being measured.
Operationally, the turbine rotor is held
between two sets of concentric cylinders
which serve to guide the flow and to
position the rotors in the pipe mounting.
As the turbine rotors resolves, each
vane generates a pulse and represent a
unit volume for flow totalization. These
meters generate a digital electrical
output which is detected by a flowmeter
or tachometer pick-up coil. The total
number of rotor revolution or output
pulses is related to the total output or
volume of flow. The frequency of the
pulses generated is directly proportional
to the flow rate of the material being
monitored or measured. The pulses
generated in the pickup coil are of sine
wave form and can be transmitted
electrically over a great distances to a
variety
of
readout
devices
for
computing,
indicating,
recording,
controlling, and automation.
—
CHAPTER 12- METROLOGY
when speed is important. This type of scale is
also a weight balance, but the weights are
mounted on bent levers, and the movement of
these pendulum levers are magnified and
transmitted to pointers that swing in a full circle.
The effective lengths of the two arms of the
pendulum lever are constantly changing; hence
to secure uniformly divided scale dials, a cam
must be interposed between pendulum and
pointer. Some form of damping mechanism
such as a fluid dashpot is used with pendulum
scales because of their high sensitiveness.
C. Installation of Volumetric Flow Meters.
All volumetric flowmeters that are subjected to
high head pressures should be protected by
means of a by-pass check valve which will
relieve the pressure in case the meter should
become jammed owing to foreign materials.
Otherwise, excessive pressure may be built up
It is also
and serious damage is done.
desirable to install the meter in a by-pass
circuit which will permit its removal for
servicing without shutting down the process.
Where a relief valve is installed to by-pass the
meter, it is essential to check it periodically to
see that it does not stick, since, if this should
happen, the meter would develop a serious
error. Where the liquid metered is hot and
likely to solidify in the meter and pipe line if
allowed to stand, it is necessary to blow the
meter with steam after each run. In this case
care must be exercised to blow the line clear
by means of a by-pass and then to clear the
meter with only a short period of blowing. If
too much pressure is used in blowing out the
meter, it is likely to race in and cause damage
to the moving parts. This is due to the excess
speed that may be developed and to the fact
that the steam may purge the meter of all
lubrication and cause galling of the parts in
sliding contact with each other. The piping
manifold should also have a draw-off
connection to permit calibration of the meter in
done
be
may
Calibration
service.
volumetrically by observing the time required
to fill a container by using a scale to check the
delivery by weight.
of
combinations
are
Scales
12.3 Electrical
mechanical elements and electrical measuring
devices. Weighing can also be accomplished by
supporting the load on hydraulic pistons,
diaphragms, or bellows units and measuring the
resulting hydraulic pressure with any convenient
pressure gage.
Section 13.0 The Three Common Methods
of Rational Speed Measurements
13.1
Section 12.0 Measurement of Weight
Weight is a primary method of measuring force and
volumetric devices are calibrated initially by weighing.
Scales have been constructed to weigh a million
kilograms or more, while the chemical balance, at the
opposite extreme will easily weigh a millionth of a
kilogram.
12.1
a common type of
Counter and Timer
revolution counter wherein the rubber of steel tip
is applied directly to the shaft center and friction
is relied upon to drive the spindle. Since the
counter is a direct reading revolution counter,
the starting and stopping errors are the chief
inaccuracies in speed measurements. The
speed indicators averages the speed over a
short period of time and indicates directly the
speed in rpm. A single button winds and starts
the watch, connects the drive shaft to the
counting after a definite period of time. With the
chronometric tachometer, the operator presses
a button to start the timing mechanism, but the
disengagement and speed indication are
automatic, and the duration of the reading is
only one (1) second. The 1-second reading are
automatically repeated by the instruments as
long as the counting and timing mechanism are
engaged.
—
13.2 Tachometer gives a direct and continuous
indications of speed and is therefore the most
convenient for observing speed variation or
fluctuations and for general observations in
which a high degree of accuracy is unnecessary.
It is made to record and applied to such
machines as turbogenerators, conveyors, paper
machines and gas engines for purposes of
control and record of performance. The electric
tachometers are made in wide variety and have
the advantage of distant location, consistent
accuracy and ease of adaptations to recording
The common Platform Scale used in the
laboratory consists of a compound leverage
system. A series of standard weights hung on
one end of the leverage system serves to
balance an unknown weight at the other end of
the system. Knife-edge fulcrums are ordinarily
used, although torsion bands or flexure plate are
introduced in large scales to eliminate friction.
12.2 Pendulum Scales give automatic indication on
over a wide range and are extensively used
256
CHAPTER 12
-
METROLOGY
and integrating. The actuating mechanism of
the common tachometer is (1) a centrifugal
device similar in construction to a centrifugal
flyball governor: (2) an electric generator or
magneto: (3) a centrifugal fan, or (4) a vibrating
red.
looms, and one additional hygrometer
for every 500 or part of 500 looms, in
excess of 500.
13.3 Stroboscope utilizes the phenomenon of
persistence of vision when an object is viewed
intermittently.
This is used for speed
measurement with indicating dials calibrated
throughout the range 700 to 14 000 rpm and
especially valuable where it is inconvenient to
make a connection or contact with the rotating
shaft or for light powered machinery where the
load to drive speed measuring instruments affect
the operation of the machine.
Section 14.0 Environmental and Pollution
Measurements
14.1
1. Weaving Department
for department with
—
One hygrometer
less than 500
257
One additional hygrometer shall be
provided and maintained outside each
cotton spinning and weaving factory
wherein
artificial
humidification
is
adopted, and in a position approved by
the inspection, for taking hygrometer
shade readings.
c.
Specification of Hygrometer
—
Provisions of Hygrometer.
In all
departments of cotton spinning and weaving
mills wherein artificial humidification is
adopted, hygrometer shall be provided and
maintained in such positions as are
approved by the Engineer. The number of
hygrometer shall be regulated according to
the following scale:
3.
—
Temperature to be recorded at each
Hygrometer.
At
each
hygrometer
maintained, correct wet and dry bulb
temperature shall e recorded daily during
working hours, except intervals for rest, by
competent persons nominated by the
Manager. The temperatures shall be taken
between 7 am/p.m. and 9 am/p.m.,
between 11 a.m./p.m. and 2 p.m.Ia.m., and
between 4 p.m/am. and 5:30 p.m./a.m. if
the factory is working during these hours. In
exceptional circumstances such additional
readings and between such hours shall be
taken. The temperatures shall be entered in
a Humidity Register maintained in the
factory. At the end of each month, the
person who have taken the readings, shall
sign the Register and certify the correctness
of the entries. The Register shall always be
available for inspection.
—
a.
Other departments
One hygrometer
for each room of less than 8 500 cubic
meters
capacity
and
one
extra
hygrometer for each 5 600 cubic meters
or part thereof, in excess of this.
b.
Humeter
instrument to measure the relative
humidity of the atmospheric air which is
important as comfort factor and is measurable of
how many airborne particulates are held in
suspension where we can take them into our
lungs as we breathe.
14.2 Hygrometer/ Psychrometer
instrument to
measure also the relative humidity of the
environment, which utilizes the physical or
electrical change of certain material s as they
absorbed moisture. It registers the temperature
difference between two primary elements, on e
of which is kept wet so that water is continuously
being evaporated from its surface. Hygrometers
that depend on physical changes employ human
hair, animal membrane, or other materials that
lengthen when it absorb water.
Electrical
hygrometers use transducers that convert
humidity variations into electrical resistance
changes. The hygrometer, humeter, or allied
instruments are used in industries where
humidity control is necessary, especially in
textile mills, paper, cigarettes manufacturing.
2.
1.
Each hygrometer shall comprise two
mercurial thermometers of wet and dry
bulb of similar construction, and equal in
dimensions, scale and divisionals of
scale. They shall be mounted on a
frame
with
suitable
a
reservoir
containing water.
2.
The wet bulb shall be closely covered
with a single layer of muslim, kept wet
by means of a wick attached to it and
dropping into the water in the reservoir.
The muslim covering and the wick shall
be suitable for the purpose, clean and
fee from size and grease.
CHAPTER 12- METROLOGY
3.
3.
No part of the wet bulb shall be within
75 mm from the dry bulb or less than 25
mm from the surface of the water in the
reservoir shall be below it, on the side of
it away from the dry bulb.
4.
The bulb shall be spherical and of
suitable dimensions and shall be freely
exposed on all sides to the aid of the
room.
5.
The bores of the streams shall be really
distinguishable at a distance of 60 cm.
6.
Each thermometer shall be graduated
so that accurate readings may be taken
between 10 to 50 degrees.
e.
An inaccurate thermometer must not be
used without fresh certificate. If an Engineer
gives notice in writing that a thermometer is
not accurate, it shall not, after one month
from the date of such notice, be seemed to
be accurate unless and until it has been re
examined as prescribed and fresh certificate
obtained which certificate shall be kept
attached to the Humidity Register.
f.
Hygrometer not to be fixed to wall, etc.,
unless protected by wood1.
7.
8.
9.
Every degree from 10 degrees up to 50
degrees shall be clearly marked by
horizontal lines on the stem, each fifth
and tenth degree shall be marked by
longer marks than the intermediate
marked opposite each fifth degree, i.e.,
10, 15, 20, 25, 30, 35, 40, 45, and 50.
No hygrometer shall be affixed to a wall,
pillar or other surface unless protected
therefrom by wood or other non
conducting material at least 12.7 mm in
thickness and distant at least 25.4 mm
from the bulb of each thermometer.
No hygrometer shall be fixed at a height
of more than 1 700 mm from the floor to
the top of thermometer stem or in the
direct droughts from a fan, window, or
ventilating opening.
No reading to be taken within 15 minutes of
renewal of water-
2.
The markings as above shall be
accurate, that is to say, at no
temperature between 10 to 50 degrees
shall be indicated readings be in error
by more than two-tenth of a degree.
g.
1.
A distinctive number shall be indelibly
marked upon the thermometer.
10. The accuracy of each thermometer shall
be certified by the Bureau of Standards,
Ministry of Trade and Industry.
d.
no water shall be applied directly to the
wick or covering during the period of
employment.
h.
Thermometers to be maintained in efficient
Each thermometer shall be
order.
maintained at all times during the period of
employment in efficient working order, so as
to give accurate indication and in particular;
No reading shall be taken for record on
any hygrometer within 15 minutes on
the renewal of water in the reservoir.
How to introduce steam fro humidification.
In any room in which steam pipes are used
for the introducing of steam for the purpose
of artificial humidification of the air, the
following provisions shall apply:
1.
The diameter of such pipes shall not
exceed 25 mm.
1.
the wick and the muslim covering of the
wet tube shall be renewed once a week;
2.
Such pipes shall be as short as is
reasonably practicable.
2.
the reservoir shall be filled with water
which shall be completely renewed once
a day. The Engineer I Manager may
direct the use of distilled water or pure
rain water in any particular mill or mills
in certain localities;
3.
All hangers supporting such pipes shall
be separated from the bare pipes by an
efficient insulator not less than 15 mm in
thickness.
4.
No uncovered jet from such pipes shall
project more than 100 mm beyond the
outer surface of any cover.
258
CHAPTER 12- METROLOGY
5.
The steam pressure shall be as low as
practicable.
6.
The pipe employed for the introduction
of steam into the air in a department
shall be effectively covered, with such
non-conducting material as may be
approved by the Engineer.
259
CHAPTER 13- MACHINE SHOP MACHINERY AND EQUIPMENT
Chapter 13
MACHINE SHOP MACHINERY AND EQUIPMENT
Section 1.0 Purpose and Scope
2.3
is ordinarily used for finishing flat or
Shaper
partly curved surfaces of metal pieces few in
number and not over 305 mm or 610 mm long.
The cutting tool has a reciprocating (forward and
return motion) and cuts on the forward stroke
only. The work is held in a vise bolted to the
work table and the regular feed is accomplished
by causing the work table to move automatically
at right angles to the direction of the cutting tool.
The construction of the tool head permits of
down feed at right angles to the regular feed, or
at any other angle if desired.
2.4
Planer a machine tool used in the production
of flat surfaces on pieces too large or too heavy
or cannot be held in a shaper. The table or
platen, on which the work is securely fastened,
has a reciprocating (forward and return) motion.
The tool head may be automatically fed
horizontally in either direction along the heavily
supported cross rail over the work and
automatic down feed is also provided.
2.5
Grinding Machine a machine tool in which an
abrasive wheel is used as a cutting tool to obtain
a very high degree of accuracy and a smooth
finish on metal parts, including soft and
hardened steel.
2.6
a machine purposely
Vertical Boring Mill
designed for finishing holes, the work table
revolves on a vertical axis and the cutting tool
(which may be a drill or a boring tool or turning
tool) is arranged above the table and may be fed
laterally (toward or away from the centre of the
table) or up or down in any position.
2.7
Horizontal Boring Mill a machine for finishing
holes where the cutting tool revolves on a
horizontal axis. The spindle which carries the
cutting tool may be fed longitudinally through the
spindle head and in the more recent designs the
spindle head may be fed vertically. The work
table may be fed longitudinally or transversely.
The horizontal boring mill, while designed
primarily for boring holes, may also be used for
finishing horizontal and vertical flat surfaces by
means of a suitable milling cutter fastened to the
spindle.
To identify each every equipment/machinery and tools
in a machine shop and the corresponding operating
principles involved.
Machine shop practice consists of certain mechanical
principles that are a part of all machine shop work
everywhere such as the principles of cutting tools,
cutting speeds and feeds, actions of gears, screws,
cams, etc., applied in the construction of certain
machines and tools and in the various machine
operations: that is, in the methods of holding and
doing work.
A machine shop is a room or space with sidings and
roofs where metal parts are cut to size required and
put together to form mechanical units or machine,
which are made to be used in the pioduction of the
necessities of civilization. One or more machines
constitute a machine shop.
Section 2.0 Standard Machine Shop
Equipment
2.1
2.2
a metal turning machine tool in which
Lathe
the work, while revolving on a horizontal axis, is
acted upon by a cutting tool which is made to
move slowly (feed) in a direction more or less
parallel to the axis of the work (longitudinal
feed), or in the direction at right angles to the
axis of the work (cross feed). Either feed may be
operated by hand or by power (automatically) as
desired. Straight turning is when feeding
direction is parallel to the axis of the work. When
the cut is in a direction at a slight angle to the
axis of the work a taper is the result, more of an
angle results in turning to an angle. The cut at
right angles to the axis of the work (cross feed
operation) is called facing or squaring. Cutting
inside of a hole is boring.
—
a machine tool used
Drill or Drill Press
in metal. In this
holes
producing
for
mainly
machine the work is securely held while a
revolving cutting tool is fed into it. The cutting
tool is termed drill.
—
260
—
—
—
—
—
CHAPTER 13— MACHINE SHOP MACHINERY AND EQUIPMENT
2.8
2.9
Universal Milling Machine a milling machine
designed and constructed that the table may be
swivelled to a considerable angle in a horizontal
plane to permit the milling of spiral (twisted)
grooves, such as are cut in twist drills, spiral
mills, etc., the work table may be moved
longitudinally, by hand or automatically, in either
direction, called the longitudinal feed or table
feed. The saddle is arranged on the knee that it
may be owned transverse by hand or power in
either direction, called cross feed. The vertical
movement of the knee may be used as a vertical
hand feed in either direction and in the larger
sizes automatic vertical feed is provided.
horizontal machines are usually of the pull type,
but vertical machines are available as pull-up,
pull down, or push down types. Most of these
machines can be arranged for efficient
production of the quantities required and where
necessary semi-automatic operations can be
employed. In these machines, the broaches are
stationary, a continuous chain conveyor with
fixtures carrying the work pieces past the
broaches.
—
3.3
Mechanical Presses
are classified on the
basis of the construction of the frame, the
mechanism for providing motion to the ram, and
whether or not it is provided with the auxiliaries
required by an automatic press. On the basis of
frame design, the presses are classified as gap
or C frame, arch type, straight side, and pillar
presses. Most presses in small and medium
sizes are mounted in vertical position or in a
titled or even horizontal position to facilitate
stock removal. Motion to the ram may be
provided by cranks, eccentrics, cams, toggles,
screws, knuckles, joints, and in one instances by
a Scoth crosshead. Mechanical presses are also
classified as single-action, double action, or
triple-action presses in which case reference is
made to the number of moving slides or rams.
3.4
Hydraulic Presses
are built in sizes varying
from 3/4 ton bench-type to huge 15,000 ton fourpost presses. Unlike mechanical presses, the
rated force or tonnage capacity is available over
the entire length of the stroke. The available
operating stroke of hydraulic presses is
substantially longer than the corresponding size
of
mechanical
press.
The
economical
applications of hydraulic presses are used
successfully
on
many
competitive
high
production, deep drawing jobs. They have also
found extensive use in the aircraft industry in
connection with rubber dies. Small and mediumsized are usually built square platens varying in
dimensions from 5161 mm
2 on up to several mm
on a side.
3.5
Shaper. Shaper cutting Tools: The variety of
cuts that may be made in a shaper on any
metals used in machine work calls for tools of
various shapes. Shaping on a shaper, can be
done to the right or to the left. It also includes
roughing
cuts,
finishing
cuts,
slotting,
contouring, under-cutting, dovetailing, and a
variety of operations. Tools can be made from
solid bars of steel, or they may be made from
smaller pieces of tool steel, called bits, which
are ground to the desired shapes and hold by
Plain Milling Machine a machine very similar
in appearance and construction to the univerSal
milling machine, differing chiefly in that it lacks
the swivel table construction. Many of the
attachments made for the universal milling
machine can be used on the plain milling
machine.
—
2.10 Vertical-Spindle Milling Machine a machine
used of any end-milling and face milling
operations, it is more adaptable than the
machine with the horizontal spindle, because
the cutter and the surface being machined are in
plain view, instead of over in back of the work.
The axis of rotation of the spindle is vertical.
—
2.11
Metal-Cutting Band Saws
a machine tool
designed to cut everything all the time, because
it employs an endless band with of sharp teeth
moving in one direction. There is no back stroke.
It cuts direct to layout lines, can saw, file and
polish work to completion using the proper and
right band tool.
—
Section 3.0 Special Tools and Machinery
in a Machine Shop of a Manufacturing
Plant
3.1
3.2
Turret Lathe
a production lathe primarily
consist of multiple-station tool holders or turrets,
in place of a lathe compound rest and tailstock.
These turrets permit the presetting of the total
number of cutters required for the job and allow
multiple and combined cuts from both turrets to
operate on the work piece.
—
Broaching Machine
There are two board
classes of broaching machines available for
performing almost any variety of broaching
operations, the vertical and the horizontal, either
of which may have one or more rams, drives are
either hydraulic or mechanically operated. Plain
—
261
—
—
CHAPTER 13- MACHINE SHOP MACHINERY AND EQUIPMENT
the tool from digging. Most shaper and planer
manufacturer recommend this type of tool for
general work.
being clamped in a tool holder. The large, solid
tools are specially good for heavy work because
they carry away the heat from the cutting edge
of the tool more rapidly, there are also tool
holders using forged bits, the tool holder with the
ground bit is probably the most popular
combination on a shaper.
The shape of the tool is also determined by the
type of work that is to be done. For the
production of an ordinary flat surface, the tool is
either right-hand or left-hand. The left-hand is
more common because it permits the operator
to see the cut better than the right-hand tool. A
dovetailing tool is naturally quite pointed. A
finishing tool is reverse, because a bread-nosed
or square-nosed tool will largely eliminate feed
marks. Whereas feed marks will be more
noticeable with a pointed tool.
Almost any
Shaping with Carbide Tools
with highmachinable
is
type of material
speed-steel cutting tools can be economically
machined with carbide tools. In situations
where the life of the tool is short, as for
machining chilled cast iron, die steel, etc., The
carbide tool is more efficient and economical.
—
There are other factors that help in the
determination of the shape of the tool. These
factors are the finish required, the kind of
material being cut, and the condition of the
machine, as well as feed and speed.
In order that a shaper may be suitable for
carbide shaping, it must be capable of speeds
exceeding 100 ft. per mm. is the absolute
minimum speed at which carbides can be
economically used. At slower speeds, there is
no appreciable difference as to cost of
operation between the high —speed tools and
the carbide tools.
The elements of a shaper tool or a planer tool is
the front rake, front clearance, side rake, etc.,
are in the same relative positions as on the lathe
tool, regardless of the fact that the shaper tool
when in use is held vertically, while the lathe tool
is held horizontally.
3.6
There is no rocker in the
Clearance Angles
tool posts of the shaper, hence the tool cannot
be adjusted for clearance the proper clearance
angles must be ground on the tool, as shown in
Fig. 3-13, the front clearance angle is 4 deg.
Planer
—
The cutting tools generally used on planers are
substantially like shaper tools for similar
operations, the only difference being the size.
a.
Round-Nosed Roughing Tool for Cast
Iron (Fig. 3-14a.) Made of high-speed steel.
General purpose, light roughing tool which
can be used in feeding from right to left or
from left to right. Since the tool has no side
rake, the depth of cut should not be more
than % in.
b.
Right-Hand Round-Nosed Roughing Tool
(Fig. 3-15a.) Made of high-speed steel. The
operator should have two of these tools for a
planer with two rail heads. They are used for
practically all roughing in cast iron.
Since the shaper feed does not operate during
the cut as does the lathe feed, a side clearance
of 2 or 3 deg. is sufficient.
Rake Angle The shaper tool is usually given
side rake angle of 10 deg. or more, depending
on the kind of tool and on the hardness of the
metal to be machined, but no front rake is given
14 shows a
except on finishing tools. Fig. 1
side-rake angle and a side-relief angle on the
cross section A-A of the tools shown directly
above.
—
—
14 carefully for a simple
Study Fig. 3
explanation of the cutting action of a shaper tool
when a plane surface is being machined. Note
that the tool is offset so as to get the tool point
toward the center of the shank. This will prevent
—
262
_
CHAPTER 13— MACHINE SHOP MACHINERY AND EQUIPMENT
f.
Left-Hand Round-Nosed Roughing Tool
for Steel (Fig. 3—17b.) Made of high-speed
steel. A campanion tool to 4, used for
roughing cuts in steel when feeding the
hesd from left toright, that is toward the
operator.
4
SIDE blank
ANGLE
c.
Right-Hand Round-Nosed Roughing Tool
for Steel (Fig. 3—14.) Made of high-speed
steel. This tool is similar to toll b but is
intended for roughing cuts in steel. The
angles of this tool are not suitable for cast
iron and, if used for that purpose, will pull in
cause chatter.
d.
Left-Hand Round-Nosed Roughing Tool
for Steel (Fig. 3—15.) Made of high-speed
steel. Use when it is necessary to feed from
left to right, toward the operator. This tool is
used for planning cast iron. For cast-steel
or forgings.
e.
Right-Hand Round-nosed Roughing Tool
for Steel (Fig. 3—17b.) Made of high-speed
steel. This tool is similar to tool b but is
intended for roughing cuts in steel. The
angles of this tool are not suitable for cast
iron and, if used for that purpose, will pull in
and chatter.
-1$
4fl60
g.
h.
Square-Nosed Roughing Tool for Cast
Iron (Fig. 3-18.) Made of high-speed steel.
For roughing cuts on flat surfaces where a
sharp corner is to be secured (Fig.3-18b).
This tool can also be used for straightening
or heavy-finishing cuts when fine finish is
not required (depth of cut 0.004 to 0.005 in.)
For lighter cuts and finer finishes, see tool 8.
This tool can also be made by brasing a
piece of high-speed steel on machine steel
shank.
Square-Nosed Finishing Tool for Cast Iron
and Steel (Fig. 3—19.) Made of high-carbon
steel. This is a general purpose tool for
straightening and finishing cuts (Fig. 3-19b.)
It is good idea to have several on and, or
different widths, from 3/8 to 1 in.
4
\__A
263
_
CHAPTER 13— MACHINE SHOP MACHINERY AND EQUIPMENT
the corners after most of the metal has been
removed by tool 9. This tool is not so well
suited for general dovetail roughing as is
tool 9, because the sharp corners
breakdown. Made of high-speed steel.
Gooseneck Finishing Tool for Cast Iron
(Fig.3-20.) Made of high-carbon steel. For
finishing flat surfaces in any metal, this tool,
in combination with a very shallow cut and
of coarse feed, is most satisfactory.
6
b
a
j.
Right-Hand Dovetail End-cutting Tool for
Cast Iron (Fig. 3-21.) Made of high-speed
steel. This tool has the cutting edge at the
end. The corner is rounded off so as to
avoid breakdown in taking the roughing cut.
It is to be followed by tool 11, which will
leave a clean, sharp angle in the corner.
End-Cutting
Dovetail
m. Left-Hand
Roughing Tool for Cast Iron (Fig. 3-24.) A
companion for tool 11, used in feeding in the
opposite direction; that is, from left to right
(Fig.3-24b.) Can be fed downward. Made of
high-speed steel.
b
a
k.
a
$
Left-Hand Dovetail End-Cutting Tool for
Cast Iron (Fig. 3-23.) A companion to tool 9,
this is to be used when feeding from, left to
right and downward (Fig. 3-23b.) It may be
followed by 12, to cut out a sharp angle.
Made of high-speed steel.
b
n.
End-Cutting
Dovetail
Right-Hand
Iron
(Fig.3-25.)
for
Cast
Tool
Finishing
Made of high-carbon steel for finishing flat
surfaces with cutting edge at the end of tool.
Used after roughing cuts with tools 9 and
11. Feed from right to left (Fig. 3-25.)
-
34
I.
,
End-Cutting
Dovetail
Right-Hand
Roughing Tool for Cast Iron (Fig. 3-24.)
similar to tool 9 and intended to clean out
264
CHAPTER 13- MACHINE SHOP MACHINERY AND EQUIPMENT
o.
Left-Hand Dovetail End-Cutting Finishing
Tool for Cast Iron (Fig. 3-26.) Made of
high-carbon steel. Companion to tool 13.
Use after tool 10 and 12. Feed from left to
right (fig. 3-26b.)
Section 4.0 Sizes of Motors for
Machine Shop Equipment and Forging
Machinery
4.1
The machines for which suitable types and sizes
of motors listed below are typical applications for
machine shop equipment and are based upon
information supplied by Westinghouse Electric
Corporation. The kilowatt values shown are for
average practice. They may be decreases for
very light work and must often be increased for
heavy work.
The type of motor be used on each case is
indicated by symbols A, B, C, etc. The meaning
of these symbols is as follows:
A
p.
Right-Hand
Dovetail
Side-Cutting
Finishing Tool for Cast Iron (Fig. 3-27a.)
Made of high-carbon steel. Used for
finishing angular surface of dovetail, as
shown in (Fig. 4-27b.) Feed downward with
coarse feed, taking a very light cut.
B
.
4
L
8
C
---
---
---
34
D
---
a
q.
E
Left-Hand
Dovetail
Side-Cutting
Finishing Tool for Cast Iron (Fig.2-30a.)
Made of high-carbon steel. Companion for
tool 15. Feed downward with a coarse feed
(Fig.2-30b.)
F
---
---
Adjustable speed, shunt-wound, direct
current motor, wherever a number of
speeds are essentials.
Constant speed, shunt-wound, direct
current motor, when the require speeds
are obtainable by a gear-box or other
adjustable speed transmission or when
only one speed is required.
Squirrel-cage induction motor, when direct
current is not available a gear-box or other
adjustable speed transmission must be
used to obtain different speeds.
Constant speed, compound-wound, directcurrent
motor,
when
speeds
are
obtainable by a gear-box or other
adjustable speed transmission or when
only one speed is required.
Wound
secondary
squirrel-cage
or
induction motors with approximately 10
percent slip, when direct current is not
available.
Adjustable speed,
direct-current motor.
compound-wound,
Section 50 Machine Screws
5.1
265
British Machine Screws
At a conference
organized by the British Standards Institution in
1965 at which the major sectors of British
industry were represented, a policy statement
was approved which urged British firms to
regard the traditional screw thread system
Withworth.
to regard the traditional screw
thread system-Withworth.
—
CHAPTER 13— MACHINE SHOP MACHINERY AND EQUIPMENT
(d) Milling Machines
(Type of Motors A, B or C)
Table 13.1
Motor Power for Machine Tools and Forging Machineries
(1) Universal Milling Machines
(a) Engines Lathes
(Type of Motor: A, B, or C)
304.8
2.2
3.7
355.6 406.4
457.2—609.6
685.8—914.4
1 066.8—137.6
1 524.0 1 828.8
3.7 5.5
7.5—5.5
15-18.5
22—30
30 -45
5.5 7.5
11 —18.522
22
37.5
—
—
Max. Feeding Movements: mm
Vertical
Lateral
Lengthwise
457.2
203.2
558.8
457.2
254
711.2
482.6
304.8
863. 6
508
355.6
1 066.8
508
355.6
1 270
Service and 1KW Rating
Heavy
Average
Swing of Lathe
mm
-
—
1KW
Rating
2.2 to 3.7
3.7 to 5.5
5.5 to 7.5
7.5 to 11
11 to 15
(2) Plane Milling Machines
(b) Cylindrical Grinding Machines
(Type of Motor: A, C, D or E)
Size of wheel
Mm
254 x19.05
254 x38.1
304.8 x31.75
304.8 x 38.1
304 8 x 63.5
355.6 x 38.1
406.4x 76.2
457.2 x 50.8
508 x50.8
508 x 63.5
609 x 50.8
609.6 x 76.6
Distance between
Centers (mm)
508 to762
508
to 762
812.8 to 1 676.4
812.8 to 1 676.4
812.8 to 1 438.4
508 to 2 184.4
762 to2286
685.8 to 3 048
914.4 to2438.4
990.6 to 4 267.2
2 438.4 to 4 267.2
2 489.2 to 4 368.8
Max. Feeding Movements: mm
Vertical
Lateral
Lengthwise
482.6
203.2
558.8
482.6
254
711.2
508
304.8
863.6
508
355.6
1 066.8
533.4
355.6
1 270
1KW Rating
1.5
1.5
3.7
3.7
7.5
3.7
5.5
5.5
7.5
9
11
18.5
to
to
to
to
to
to
to
to
to
to
to
to
3
3
6
6
9
6
7.5
7.5
11
11
15
26
(3) Milling Machines
Max. Feeding Movements: mm
Vertical
Lateral
Lengthwise
457.2
304.8
558.8
508
330.2
558.8
588.8
355
863.6
588.8
381
1 066.8
609.6
304.8
1 320.8
(c) Punch Presses
(Type of Motor: A, C, D or E)
Soft Steel
mm
6.35
9.525
12.7
15.875
19.05
22.225
25.4
31.75
38.1
44.45
50.8
57.15
57.15
63.5
76.2
101.6
152.4
Thickness
mm
6.35
9.525
12.7
15.875
19.05
22.225
25.4
25.4
25.4
25.4
25.4
28.575
34.925
38.1
50.8
38.1
38.1
1KW
Rating
2.2
3.7to5.5
5.5 to 7.5
7.5 to 11
11 to 15
KW Rating
1KW
Rating
2.2 to 3.7
3.7 to 5.5
5.5 to 7.5
7.5 toll
11 to 15
(4) Horizontal Boring, Drilling & Milling Machines
(Type of Motor: A, B or C)
0.37 to 0.75
0.37 to 1
0.5to2.2
1 to 1.5
0.75 to 3.7
1 to 3.7
1.5 to 4.5
2.2 to 6
5.5
7.5
7.5
7.5toll
11 to 15
lltol5
15 to 18.5
18.5
30
Spindle
Diam., mm
88.9—114.3
127
Horsepow
er
11— 18.5
15-22
Spindle
Diam., mm
165.1
177.8—241.3
1KW
Rating
15—22
22—30
(e) Hydraulic Wheel Presses
(Type of Motor: B or C)
Capacity,
Tons
100
200
300
266
KW
Rating
2.2—2.6
3.7—5.5
4.5 5.5
—
Capacity,
Tons
400
500
1KW
Rating
5.5—7.5
7.5—11
9.3 11
—
CHAPTER 13— MACHINE SHOP MACHINERY AND EQUIPMENT
(b) Cylindrical Grinding Machines
(Type of Motor: A, C, D or E)
Vertical TvDe
Soft Steel’•
Width, mm
preference an intermediate change to ISO inch
threads.
5.2
Thickness
of
Plate, mm
0.79375
1.5875
3.175
4.7625
6.35
9.525
762 to 1 066.8
914 to 1 574.8
914to3657.6
914.4 to 3657.6
1 066.8 to 4 267.2
1 371.6to3200.4
Table 13.1 (Continued)
Soft Steel
Square Bar, KW Rating
Size mm
19.05
1.5 to 3.7
25.4
2.2 to 3.7
31.75
3.7 to 5.5
38.1
3.7 to 5.5
44.45
3.7 to 7.5
50.8
5.5to9
57.15
7.5toll
KW Rating
—
0.5 to 0.75
1.5 to 2.2
2.2to7.5
3 to 9
4.5 to 15
lltol5
LeverT
Soft Steel,
Square Bar,
Size mm
63.5
69.85
76.2
82.55
88.9
101.6
pe
KW Rating
5.3
7.5 to 15
11 to 15
11 to 18.5
15 to 22
15 to 30
22to37
.....
(g) Bolt Heading, Upsetting and Forging Machinery
(Type of Motor: D, E or F)
Size, mm
31.75
38.1
50.8
63.5
KW Rating
7.5
11
15
18.5
Size, mm
76.2
101.6
127
152.4
KW Rating
22
37
45
55
(h) Bulldozers or Forming or Bending Machines
(Type of Motor: D or E)
Width, mm
736.6
863.6
990.6
1 143
1 600.2
Head Movement,
mm
355.6
406.4
406.4
457.2
508
British Standard Machine Screws and
Machine Screw Nuts, Metric Series
British
Standard B.S. 4183: 1967 gives dimensions and
tolerances for; countersunk head, raised
countersunk head, and cheese head slotted
screws in a diameter range from Ml (1mm) to
M20 (20 mm); pan head slotted head screws in
a diameter range from M2.5 (2.5 mm) to M10
(10 mm); and square and hexagon machine
screw nuts in a diameter range from M 1.6 (1.6
mm) to M 10 (10 mm). Mechanical Properties
are also specified for steel, brass and aluminium
alloy machine screws and machine screw nuts
in this standard.
Material The materials from which the screws
and nuts are manufactured have a tensile
strength not less than the following: steel, 40
2 (392 N/mm
kgf/mm
); brass, 32 kgf/mm
2
2 (314
); and aluminium alloy, 32 kgf/mm
2
N/mm
( 314
2
). The unit, kgf/mm
2
N/mm
2 is in accordance with
ISO DR 911 and the unit in parenthesis has the
relationship, 1 kgf = 9.80665 Newtons. These
minimum strengths are applicable to the finished
products. Steel machine screws conform to the
requirements for strength grade designation 4.8.
The strength grade designation system for
machine screws consists of two figures, the first
is 1/10 of the minimum tensile strength in
kgf/mm2, the second is 1/10 of the ratio
between the yield stress and the minimum
tensile strength expressed as a percentage;
1/10 minimum tensile strength of 40 kgf/mm
2
gives the symbol “4”; 1/10 ratio giving the
strength grade
—
KW Rating
yield stress
mm. tensile strength
3.7
5.5
7.5
11
15
5.4
=
1 x 32 x
10
40
100
1
=
“8”
Isometric screw threads are designated
according to the following examples: M5 x 0.8
6H for an internal thread and M8 x 1.25 6g for
an external thread where M denotes the thread
system symbol for ISO metric thread, the 5 and
8 denote the nominal size in millimetres, the 0.8
and 1.25 denote the pitch in millimetres and 6H
and 6g denote the thread tolerance.
—
—
B.A. and B.S.F. as obsolescent, and to make
the internationally agreed ISO metric thread
their first choice (with ISO Unified thread as
second choice) for all future designs. It is
recognized that some sections of British industry
already using ISO inch (UNIFIED) screw threads
may find it necessary, for various reasons, over
be superseded by ISO metric threads in
—
5.5
267
Length of Thread on Screws
Screws of
nominal thread diameter Ml, M1.2 and M 1.4
and screws of larger diameters which are too
—
CHAPTER 13- MACHINE SHOP MACHINERY AND EQUIPMENT
with cut threads are normally finished with a
chamfer conforming to the dimension. At the
option of the manufacturer, the ends of screws
smaller than M6 (6mm diameter) may be
finished, with a radius approximately equal to 1
1/
times the nominal diameter of the shank.
short for the thread lengths are threaded as fast
as possible up to the head. In these the length
of unthreaded shank under the head does not
exceed 1 % pitches for lengths up to twice the
diameter and 2 pitches for longer lengths, and is
defined as the distance from the leading face of
a nut which has been screwed as far as possible
onto the screw by hand to: 1) the junction of the
basic major diameter and the countersunk
portion of the head on countersunk and raised
countersunk head; 2) the underside of the head
on other types of heads. Screws of nominal
thread diameter Ml, M 1.2 and M 1.4 and
screws of larger diameters which are too short
for the thread lengths are threaded as far as
possible up to the head. In these the length of
unthreaded shank under the head does not
exceed 1 1/2 pitches for lengths up to twice the
diameter and 2 pitches for longer lengths, and is
defined as the distance from the leading face of
a nut which has been screwed as far as possible
onto the screw by hand to: 1) the junction of the
basic major diameter and the countersunk
portion of the heed on countersunk and raised
countersunk heads; 2) the underside of the head
on other types of heads.
5.6
5.7
5.8
Section 6.0 Gearing
6.1
Diameter of Unthreaded Shank on Screws
The diameter of the unthreaded portion of the
shank on screw is not greater than the basic
major diameter of the screw is not greater than
the basic major diameter of the screw head and
not less than the minimum effective diameter of
the screw thread. The diameter of the
unthreaded portion of shank is closely
associated with the method of manufacturer; it
will generally be nearer the major diameter of
the thread for turned screws and nearer the
effective diameter for those produced by cold
heading.
The terms which
Definition of Gear Terms
follow are commonly applied to various classes
of gearing.
—
a.
Height of tooth above pitch
Addendum
between the pitch
distances
the
circle of
circle and the top of the tooth.
b.
Arc of the pitch circle
Arc of Action
through which a tooth travels from the first
point of contact with the mating tooth to the
pitch point.
c.
Arc of Approach Arc of the circle through
which a tooth travels from the point of
contact with the mating tooth to the pitch
d.
Arc of the pitch circle
Arc of Recess
through which a tooth travels from its
contact with the mating tooth at the pitch
point to the point where is contact ceases.
e.
In a pair of gears it is the
Axial Plane
plane that contains the two axes, in a single
gear, it may be any plane containing axis
and the given point.
f.
Backlash The amount by which the width
of a tooth space exceeds the thickness of
the engaging tooth on the pitch circles. As
actually indicated by measuring devices,
backlash may be determined variously in the
transverse, normal or axial planes, and
either in the direction of the pitch circles or
on the lines of action. Such measurements
should be converted to corresponding
—
—
The
Radius Under the Head of Screws
radius under the head of pan and cheese head
screws runs smoothly into the face of the head
and shank without any step of discontinuity. A
true radius is not essential providing that the
curve is smooth and lies wholly within th
maximum radius. Any radius under the head of
countersunk head screws runs smoothly into the
conical bearing surface of the head and the
shank without any step or discontinuity.
—
—
—
—
Ends of Screws When screws are made with
rolled threads the “lead” formed by the thread
rolling operation is normally regarded as
providing the necessary chamfer and no other
machining is necessary. The ends of screws
-
268
—
—
CHAPTER 13- MACHINE SHOP MACHINERY AND EQUIPMENT
values on transverse
general comparisons.
pitch
circles
for
g.
Base Circle
The circle from which an
involute tooth is generated or developed.
h.
Base Helix Angle The angle, at the base
cylinder if an involute gear, that the tooth
makes with the gear axis.
p.
Clearance
The amount by which the
dedendum in a given gear. It is also the
radial distance between the top of a tooth
and bottoms of the mating tooth space.
q.
Central Diameter The smallest diameter
on a gear tooth with which the mating gear
makes contact.
r.
Contact Ratio
The ration of the arc of
action to the circular pitch. It is sometimes
thought of as the average number of teeth in
contact. For involute gears, the contact ratio
is obtain most directly as the ratio is obtain
most directly as the ratio of the length of
action to the base pitch.
s.
Cycloid The curve formed by the path of a
point on a circle as it rolls along a straight
line. When this circle tools along the outer
side of another circle, the curve is called an
Epicycloid; when it rolls along the inner side
of another circle it is called a 1-lypocycloid.
These curves are used in defining the
American former Standard composite tooth
form.
t.
Dedendum
The depth of tooth space
below the pitch circle of the radial dimension
between the pitch circle and the bottoms of
the tooth space.
u.
Diametral Pitch
The ratio of the number
of teeth to the number of millimetres of pitch
diameter-equals number of gear teeth to
each mm pitch diameter. Normal Diametral
Pitch is the diametral pitch as calculated in
the normal plane and is equal to the
diametral pitch divided by the cosine of helix
angle.
v.
Effective Face Width That portion of the
face width that actually comes into contact
with mating teeth, as occasionally one
member of a pair of gears may have a
greater face width than the other.
b.
Efficiency
The actual torque ratio of a
gear set divided by its gear ratio.
x.
External Gear
A gear with teeth on the
outer cylindrical surface.
y.
Face of Tooth
That surface of the tooth
which is between the pitch circle in the top
of the tooth.
-
—
Base Pitch
In an involute gear it is the
pitch on the base circle or along the line of
action. Corresponding sides of involute teeth
are parallel curves, and the base pitch is the
constant and fundamental distance between
them along a common normal in a plane of
rotation. The normal Base Pitch is the base
pitch in the normal plane, and the Axial
Base Pitch is the base pitch in the axial
plane.
—
j.
k.
Center Distance
The distance between
the parallel axes of spur gears and parallel
helical gears, or between the crossed axes
or crossed helical gears, or between the
crossed axes or crossed helical gears and
worm gears. Also, it is the distance between
the centers of the pitch circles.
—
Central Plane
In a worm gear this is the
plane perpendicular to the gear axis and
contains the common perpendicular of the
gear and worm axes. In the usual case with
the axes at right angles, it contains the
worm axis.
—
Chordal Addendum The height from the
top of the tooth to the chord subtending the
circular-thickness arc.
—
m. Chordal Thickness
Length of the chord
subtended by the circular thickness arc (the
dimension obtained when a geartooth
caliper is used to measure the thickness at
the pitch circle.
—
—
—
—
—
—
—
n.
o.
Circular Pitch
Length of the arc of the
pitch circle between the centers or other
corresponding points of adjacent teeth.
Normal Circular Pitch is the circular pitch in
the normal plane.
—
—
Circular Thickness
The length of arc
between the two sides of a gear tooth, on
the pitch circles unless otherwise specified.
Normal Circular Thickness is the circular
thickness in the normal plane.
—
—
—
269
—
CHAPTER 13— MACHINE SHOP MACHINERY AND EQUIPMENT
Face Width The length of the teeth in the
axial plane. The effective face width is the
width which actually makes contact with the
mating gear. When herringbone gears have
a central clearance groove, the width of this
groove is not included in the effective face
width.
point of contact moves during the action of
the tooth profile.
The concave portion of the
aa. Fillet Curve
tooth profile where it joins the bottom of the
tooth space. The approximate radius of this
curve is called the Fillet Radius.
mm. Lowest Point of Single Tooth Contact
The smallest diameter on a spur gear at
which a single tooth of one gear is in contact
with its mating gear, often referred to as
LPSTC. Gear set contact stress is
determined with a load placed at this point
on the pinion.
z.
—
The path of contact in
Line of Action
the straight line passing
is
It
gears.
involute
through the pitch point and tangent to the
base circles.
—
—
—
That surface which is
bb. Flank of Tooth
between the pitch circle and the bottom
land. The flank includes the fillet.
—
nn. Module Ratio of the pitch diameter to the
number of teeth. Ordinarily, module is
understood to mean ratio of pitch diameter
in millimetre to the number of teeth. The
English Module is a ratio of the pitch
diameter in inches to the number of teeth.
—
The effective face width
cc. Helical Overlap
of a helical gear divided by the gear axial
pitch; also called the Face Overlap.
—
dd. Helix Angle The angle that a helical gear
tooth makes the gear axis.
—
oo. Normal Plane A plane normal to the tooth
surfaces at a point of contact, and
perpendicular to the pitch plane.
—
ee. Highest point of Single Tooth Contact
The largest diameter on a spur gear at
which a single tooth is in c’ntact with the
mating gear. Often referred to as HPSTC.
Gear tooth fillet stress is determined with the
operating load placed at this diameter.
—
if.
The distance between similar,
pp. Pitch
equally-spaced tooth surfaces in a given
direction and along a given curve or line.
The single word “pitch” without qualification
has been used to designate circular pitch,
axial pitch, and diametral pitch, but such
confusing usage should be avoided.
—
Internal Diameter The diameter of a circle
coinciding with the tops of the teeth of an
internal gear.
—
qq. Pitch Circle A circle the radius of which is
equal to the distance from the gear axis to
the pitch point.
A gear with teeth on the
gg. Internal Gear
inner cylindrical surface.
—
—
hh. Involute The curve formed by the path of
a point on a straight line, called the
generatrix, as it rolls along a convex base
curve. (The base curve is usually a circle.)
This curve is generally used as the profile of
gear teeth.
—
ii.
Land The top Land is the top surface of a
tooth, and the Bottom Land is the surface of
the gear between the fillets of adjacent
teeth.
jj.
The distance a helical gear or
Lead
woman would thread along its axis one
revolution of it were free to move axially.
rr.
Pitch Diameter The diameter of the pitch
circle. In parallel shaft gears the pitch
diameter can be determined directly from
the distance and the numbers of teeth by
proportionality. Operating Pitch Diameter is
the pitch diameter at which the gears
operate. Generating Pitch Diameter is the
pitch diameter at which the outer ends of the
teeth unless otherwise specified.
ss.
In a pair of gears it is the
Pitch Plane
plane perpendicular to the axial plane and
tangent to the pitch surface. In a single gear
it may be any plane tangent to its pitch
surface.
tt.
Pitch Point This is the point of tangency
of two pitch circles (or of a pitch circle and a
—
—
The distance on an
kk. Length of Action
involute line of action through which the
—
—
—
270
—
CHAPTER 13- MACHINE SHOP MACHINERY AND EQUIPMENT
pitch line) and is on the line of center. The
pitch point of a tooth profile is at its
intersection with the pitch circle.
uu. Plane Rotation
to a gear axis.
ccc. Tangent Plane
A plane tangent to the
tooth surfaces at a point or line of contact of
material is removed near the tip of the gear
tooth.
—
Any plane perpendicular
—
ddd. Tip Relief
An arbitrary modification of a
tooth profile whereby a small amount of
material is removed near the tip of the gear
tooth.
—
vv. Pressure Angle
The angle between a
tooth profile and a radical line at its pitch
point. In involute teeth, pressure angle is
often described as the angle between the
line of action and the line tangent to the
pitch circle. Standard Pressure Angles are
established in connection with standard
gear-tooth proportions. A given pair of
involute profiles will transmit smooth motion
at the same velocity ratio even when the
center distance is changed.
—
eee. Total Face Width
The actual width
dimension of a gear blank. It may exceed
the effective face width, as in the case of
double-helical gears where the total face
width includes any distance separating the
right-hand and left-hand helical teeth.
—
iff. Transverse Plane A plane perpendicular
to the axial plane and to the pitch plane. [n
gears with parallel axes, the transverse
plane and the plane of rotation coincide.
—
ww. Principal Reference Planes These are a
pitch plane, axial plane, and transverse
plane, all intersecting at a point and mutually
perpendicular.
—
ggg. Trochoid The curve formed by the path of
a point on the extension of a circle as it rolls
along a curve or line. It is also the curve
formed by the path of a point on a
perpendicular to a straight line as the
straight line rolls along the convex side of a
base curve. By the first definition the
trochoid is a derivative of the cycloid; by the
second definition it is derivative of the
involve.
—
xx. A gear with teeth spaced along a straight
line, and suitable for straight line motion. A
Basic Rack is one that is adopted as the
basis of a system of interchangeable gears.
Standard gear-tooth proportions are often
illustrated on an outline used to indicate
tooth details and dimensions for the design
of a required generating tool, such as a hob
or gearshaper cutter.
hhh. True Involute Form Diameter
The
smallest diameter on the tooth at which the
involute exits. Usually this is the point of
tangency of the involute tooth profile and the
fillet curve. This is usually referred to as the
TIP diameter.
—
yy. Ratio of Gearing Ratio of the numbers of
teeth on mating gears. Ordinarily the ratio is
found by dividing the number of teeth on the
larger by the number of teeth on the smaller
gear or pinion. For example, if the ratio is “2
or 3 to 1”, this usually means that the
smaller gear or pinion makes two
revolutions to one revolution of the larger
mating gear.
—
zz. Roll Angle
The angle subtended at the
center of a base circle from the origin of an
involute to the point of tangency of the
generatrix from any point on the same
involute. The radian measure of this angle is
the tangent of the pressure angle of the
point on the involute.
iii.
Undercut
A condition in generated gear
teeth when any part of the fillet curve lies
inside of a line drawn tangent to the working
profile at its lowest point. Undercut may be
deliberately introduced to facilitate finishing
operations, as in pre-shaving.
jjj.
Whole Depth
The total depth of a tooth
space, equal to addendum plus dedendum,
also equal to working depth plus clearance.
kkk.
Working Depth The depth of engagement
of two gears, that is, the sum of their
addendum’s. The standard working distance
is the depth to which a tooth extends into
the tooth space of a mating gear when the
center distance is standard.
—
aaa. Root Circle
A circle coinciding with or
tangent to the bottoms of the tooth spaces.
—
bbb. Root Diameter
—
Diameter of the root circle.
271
—
—
—
CHAPTER 13— MACHINE SHOP MACHINERY AND EQUIPMENT
Pressure Angle
=
0
Addendum
=
a
Dedendum
=
b
Clearance
=
c
Center Distance
=
C
Pitch Diameter
=
D
Base Circle Diameter
=
Db
Outside Diameter
=
0
D
Root Diameter
=
DR
Face Width
=
F
Working Depth of Tooth
=
hk
Whole Depth of Tooth
=
h
Number of Teeth
=
N
If both gear and pinion are referred to:
Number of Teeth in Gear
=
NG
Number of Teeth in Pinion
=
N
Circular Pitch
=
p
Diatmetral Pitch
=
P
1
To Find
General Formulas
Db
Base Circle Diameter
2a
Circular Pitch
2b
No.
Outside Diameter
(American Std. Stub
Teeth)
0
D
8
Outside Diameter
0
D
=
D
9a
Pitch Diameter
D
=
N
P
10
Root Diameter
DR
=
D
7b
Table 13.2
Formulas for Dimensions of Standard Spur Gear
Notations
6.2
D cos
p
=
3.1416D
N
Circular Pitch
p
=
3.1416
P
3a
Center Distance
C
=
Ng+Np
2P
3b
Center Distance
C
=
0
6.3
N
4a
Diametrical Pitch
P
=
3.1416
P
5a
Number of Teeth
N
=
PxD
5b
Number of Teeth
N
=
3.1416
p
6a
Outside Diameter:
(Full-depth Teeth)
0
D
=
N+2
P
6b
Outside Diameter:
(Full-depth Teeth)
0
D
=
(N+2)r
3.1416
7a
Outside Diameter
(American Std. Stub
Teeth)
0
D
=
N+1.6
P
(N+1.6)p
3. 1416
+
—
2a
2b
Outside and Root Diameters of Hobbed,
Shaped, or Pre-shaped Gears Formulas are
given for finding the outside and root diameters
of spur gears with various types of standard
teeth using the data for pitch diameters,
addenda, and the dedenda. It will be noted from
the formula given that the root diameter for a
gear of given pressure angle and type of tooth
depends upon whether the gear is being
hobbed, shaped, or pre-shaved. When gears
are finish-hobbed the standard preferred
dedendum is used. When gears are cut on the
generating type of gear shaper the clearance is
made larger so that a dedendum greater than
standard is required. In preparing gears for
shaving, it is necessary to semi-finish hob or
shape the gears deeper than standard depth in
order to avoid interference between the tips of
the shaving cutter teeth and the fillet at the base
of the gear tooth.
—
Formula
=
=
Tooth Thickness Allowance for Shaving
Proper stock allowance is important for good
results in shaving operations. If much stock is
left for shaving, the life of the shaving tool is
reduced and, in addition, shaving time is
increased. The following figures represent the
amount of stock to be left on the teeth for
removal by shaving under average conditions.
For diametral pitches of 2 to 4, a thickness of
.0762 mm to .1016 mm (one-half on each side
of tooth); for 5 to 6 diametral pitch, .0635 to
0.0890 mm; for 7 to 10 diametral pitch, 0.0508
to 0.0762 mm; for 11 to 14 diametral pitch,
0.0381 to 0.0508 mm; for 16 to 18 diametral
pitch, 0.0254 mm to 0.0508 mm; for 20 to 48
diametral pitch, 0.1270 to 0.03810 mm; and 52
to 72 diametral pitch, 0.0762 to 0.01 778 mm.
—
The thickness of the gear teeth may be
measured in several ways to determine the
amount of stock left on the sides of the teeth to
be removed by shaving. If it is necessary to
measure the tooth thickness during the pre
shaving operations while the gear is in the gear
272
CHAPTER 13- MACHINE SHOP MACHINERY AND EQUIPMENT
6.4
shaper or hobbing machine, a gear tooth caliper
or pins would be employed.
b.
The root radius may vary within the limits
0.25 to 0.39.
When the pre-shaved gear can be removed
from the machine for checking, the center
distance method may be employed. In this
method, the pre-shaved gear is mashed without
backlash with a gear of standard tooth thickness
and the increase in center distance over
standard is noted. The amount of total tooth
thickness over standard is left on the pre-shaved
gear can then be determine by the formula: t
2 =
2 tan 0 x d, where: t
2 = amount that total
thickness of the tooth.
c.
Tip relief may be applied within the limits
shown.
British Standard Spur and Helical Gears
0.02
EZ\J
0.39
—
Metric modules (R.S. 436: Part 2: 1970). The
British Standard is a metric-unit specifications
for external and internal spur and helical gears
for use with parallel shafts. Preferred and
second choice modules are given, and the
requirements for the basic rack tooth profile, and
accuracy are covered. Any of ten different
grades of accuracy may be applied to each gear
element. Thus gear requirements are met
ranging from course commercial to high-speed
and high-lead precision applications. Tolerances
on gear blanks are included in the
specifications. The standard is a companion
specifications. The standard is a companion
specification to B.S. 436: Part 1: 1967, which
covers the requirements of spur and helical
gears in the inch system.
6.5
Notation To promote the international usage
of common gear terminology, the terms of draft
ISO Recommendation No. 888, International
vocabulary of gears’ have been adopted, and
the
notation
is
derived
from
ISO
Recommendation R701 ‘International gear
notation, symbols for geometrical data.
6.6
Basic Rack Tooth Profile
The basic rack is
generally
in
agreement
with
ISO
Recommendation R
53 ‘Basic rack of cylindrical
Fig.
13.6.6
(Left) British Basic Rack Tooth Profile
for Unit Normal Metric Module, and (Right)
Limits of Tip Relief (B.S. 436: Part 2: 1970)
Tolerance can also be calculated using the
appropriate formula given in the pitch tolerance
sub-table in Table 13.4. Thus, for a gear of
grade 6 accuracy, the formula is 2.5 J 1 + 6.3.
Substituting 40 mm arc length, the calculation is
2.5 40 ÷ 6.3 = 2.5 x 6.32 + 6.3 = 22.1
micrometers, which rounded down is 0.022 mm.
6.7
—
Gear Design upon Module System
The
module of a gear equals the pitch diameter
divided by the number of teeth, whereas
diametral pitch equals the number of teeth
divided by the pitch diameter. The module
system is in general use in countries which have
adopted the metric system; hence the term
module is usually understood to mean the pitch
diameter in millimetres divided by the number of
teeth. The module system
—
Table 13.3
British Standard Spur and Helical Gears Standard
Normal Metric Modules (B.S. 436: Part 2: 1970)
—
—
gears for general and heavy engineering.’ In
practice, the basic rack tooth is usually modified,
and the extent of modification shall be in
accordance with the following:
a.
max
06
max
Preferred 1
4
5
6
1.25 1.5 2
2.5 3
Modules
Second
1.13 1.38 1.75 2.25 2.75 3.5 4.5 5.5 7
Choice
Modules
The total depth may vary within the limits
2.25 to 2.40 which permits an increasing
root clearance within the same limits to
allow for the use of different manufacturing
processes.
Preferred 8
Modules
Second
9
Choice
Modules
273
10
12
16
20
25
32
40
11
14
18
22
28
25
45
50
CHAPTER 13— MACHINE SHOP MACHINERY AND EQUIPMENT
0.63 øf + 6.3
1.0 øf + 8.0
1.6 øf+ 10.0
2.5 øf+ 16.0
4.Oøf+25.0
1 .0/b + 5.0
1 .25/b + 6.3
2.0/b + 10.0
14.0/1+35.0
20.0/1 + 50.0
6.3øf+40.9
10.0 øf + 63.0
8.0/b+40.0
12.5/b + 63.0
Gear
Accur
acy
Grade
Limits of
Tolerance
on Radial
Run out of
Teeth
Limits of
Tolerance on
Tooth-toTooth
Composite
Error
Limits of
Tolerance
on Total
Composite
Error
3
4
5
6
7
8
9
10
11
12
0.56 øp + 7.1
0.90 øp+ 11.2
1.40 p + 18.0
2.24 øp + 28.0
3.15 øp ÷ 40.0
4.0 øp + 50.0
5.0 øp + 63.0
6.3 øp + 80.0
8.Oøp+ 100.0
10.0 øp+125.0
0.32 p + 4.0
0.45øp+5.6
0.63 p + 8.0
0.9 øp ÷ 11.2
1.25 øp +16.0
1.8 øp + 22.4
2.24 øp+28.0
2.8 p + 35.5
3.55øp45.0
4.5 øp + 56.0
0.8 øp + 10
1.25 øp+ 16.0
2.0 øp + 25.0
3.l5øp + 40.0
4.5 øp + 56.0
5.6 øp + 71.0
7.1 øp + 90.0
9.0 øp ÷ 112.0
ll.2øp+l4O.0
l4.Oøp+18O.0
The values are in millimetres.
*Wherever possible, the preferred modules should be
applied rather than those of second choice.
Te flanks or sides are straight (invoiste system) and the pressure angte is 20 degrees.
The shape of the root stearance space and the amount of clearance defend upon the method
of cutting and special requirements. The amount of clearance may vary from 0.1 x rnoduln to
0.3 x module.
To Find
Addendum
Dedendum
Working Depth
Total Depth
Total Thickness on
Pitch Line
Circular Pitch known
Module Known
Equals module 0.3 183 x circular pitch*
1.157 x module* 0.3183 x Circular pitch*
1.167 x module* 0.3ll4xCircularpitch**
0.6366 x Circular pitch**
2 x module
1.157 x module* 0.6866 x Circular pitch**
1.167 x module** 0.6896 x Circular pitch
6
7
8
2.5/1
+
3.55/1
+
5.1/1
+
9
7.1/1
+
10
10.0/1
+
11
12
6.3
9.0
12.5
18.0
25.0
3.15/b +16.0
5.0/b+ 25.0
1.5708 x module 0.5 x Circular pitch**
The Limits of Tolerance are in micro-meters.
Fig.13.6.7 German Standard Tooth Form form Spur
and Bevel Gears.
The values of symbols given in the above formulas
are:
number of teeth. The module system may,
inch
upon
based
also
be
however,
measurements and then it is known as English
module to avoid confusion with the metric
module. Module is an actual dimension,
whereas diametral pitch is only a ratio. Thus, if
the pitch diameter of a gear is 50 millimeters
and the number of teeth 25, the module is 2
which means that there are 2 millimeters of
pitch diameter of each tooth. Table 13.6
“Tooth Dimensions Based Upon Module
System” shows the relation between module,
diametral pitch, and circular pitch.
Table 13.4
British Standard Metric Spur and Helical Gears
Basic Formulas for Limits of Tolerance on
Elements (B.S. 436: Part 2: 1970)
Gear Limits of
Accura Tolerance
on Pitch
cy
Grade
0.63/1+ 1.6
3
4
1.0/1 + 2.5
1.6/1 + 4.0
5
I
Limits of
Tolerance
Tooth
Alignment
0.l6øf+3.15
0.25øf+4.0
0.40 øf + 5.0
0.5/b+2.5
0.63/b+3.15
0.80/b + 4.0
any selected length of arc in millimetres, are less
than d/2.
of = ma + 0.1 d, where ma = normal module, and
d = reference circle diameter in mm.
b
=
face width in mm, up to a maximum of 150 mm.
op = ma + 0.25 d, where ma
d = reference circle dia.
=
normal module, and
(*) are
Formulas for dedendum and total depth marked
x
module.
used when clearance equals 0.157
Formulas marked (**) are used when clearance equals
one-sixth module. It is the common practice among
American cutter manufacturers to make the clearance
of metric module cutters equal to 0.157 x module.
—
Limits of
Tolerance
Tooth
on
Profile
=
on
274
CHAPTER 13- MACHINE SHOP MACHINERY AND EQUIPMENT
Table 13.5
Rules for Module System of Gearing
Diametral
Pitch
Equivalent to
Metric
Module
Rule 1: To find the metric module, divide
the pitch diameter in millimetres by the
number of teeth.
Example: The module is 12; determine
equivalent diametral pitch
Example 1: The pitch diameter of a gear
is 200 millimeters and the number of
teeth, 40; then
module
Metric
Module
Rule: To find the diametral pitch
equivalent to a given module, divide 25.4
by the module (25.4 = number of
millimeters per inch.)
equivalent diametral pitch
200 = 5
40
Rule 2: Multiply circular pitch in
millimetres by 0.3183
15.708 x 0.31 83
Pitch
Diameter
Outside
Diameter
40 x 8
=
320 millimeters
=
12.598
inches
Rule: Add 2 to the number of teeth and
multiply sum by the module.
Outside Diameter
Rule: To find the English module, divide
the pitch diameter in inches by the
number of teeth.
=
=
Example: A gear has 40 teeth and
module is 6. Find outside or blank
diameter.
Note: The module system is usually
applied when gear dimensions are
expressed in millimeters, but module
may also be based upon inch
measurements.
module
2:17
Example: The metric module is 8 and
gear has 40 teeth; then
5
Rule 3: Divide outside diameter in
millimeters by the number of teeth plus
2.
English
Module
=
Rule: Multiply number of teeth by module
d
=
25A
12
Note: A diametral pitch of 2 is nearest
standard of equivalent.
=
Example 2: (Same as example 1.
Circular pitch of this gear equals 15.708
millimeters).
module
=
(40
+
2) X 6 = 252
millimeters.
Section 7.0 Guarding of Point of
Operating in Turning, Drilling, Shaping,
Milling and Grinding Operations.
12 1 module or 4 diametral
48 4
pitch
7.1
Turning Machines
Machines performing
turning operations
include engine lathes,
turrets lathes, hollow spindle lathes, automatic
lathes and automatic screw machines.
—.
—
Rule: To find the metric module
equivalent to a given diametral pitch,
divide 25.4 by the diametral pitch.
Type of Accidents
Example: Determine metric module
Metric
equivalent to 10 diametral pitch
Module
Equivalent to
equivalent module = 25.4 = 2.54
Diatmetral
10
Pitch
Note: The nearest standard module is
2.5
275
Suitable Guards
(a) Contact with
projections of
face plates
(1) Head-stock guard
(2) Chuck guard
(b) Contact with
projection to
the dogs and
projecting set
screws
(1) Counter sunk screw
CHAPTER 13— MACHINE SHOP MACHINERY AND EQUIPMENT
(c) Flying of metal
chips or long
burrs and
turnings
(d) Hand braking
of machines
(1) Enclosure guard
(2) Portable perspex
screenguard
(3) Use chip breaker-tool to
eliminate long turnings
(1) Foot-pedal brake with
triple-switch
(2) Pneumatic chuck and
freeding tools for small
jobs
(e) Filling
emerging
without a
suitable device
(1) Automatic emerging
Emery holder
(f) Gauging the
job while
machine is in
motion.
(1) Dial indicators.
(g) Attempting to
clean chips
when job is in
motion.
(1) Safety hook/brush.
Table 13.6
Tooth Dimensions Based Upon Module System
Me
DIN
Standar
dSeries
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.25
1.5
1.75
2
2.25
2.5
2.75
3
3.25
3.5
3.75
4
4.5
5
5.5
6
6.5
7
(h) Projection of
the work or
stock
beyond
machine
(i)
(j)
(1) Tube guard
(2) Bar-stock guard
8
9
10
11
12
13
14
15
16
18
20
22
24
27
30
33
36
39
42
45
50
55
60
65
70
75
Equivalent
Diametral
Pitch
84.667
63.500
50.800
42.333
36.286
31 .750
28.222
25.400
20.320
16.933
14.514
12.700
11.289
10.160
9.236
8.466
7.815
7.257
6.773
6.350
5.644
5.080
4.618
4.233
3.908
3.628
3.175
2.822
2.540
2.309
2.117
1.954
1.8 14
1.693
1.587
1.411
1.270
1.155
1.058
0.941
0.847
0.770
0.706
0.651
0.605
0.564
0.508
0.462
0.423
0.391
0.363
0.339
Circular Pitch
J Millimet
ers
0.943
1.257
1.57 1
1.885
2.199
2.513
2.827
3.142
3.927
4.712
5.498
6.283
7.069
7.854
8.639
9.425
10.2 10
10.996
11.781
12.566
14. 137
15.708
17.279
18.850
20.420
21.991
25.132
28.274
31 .416
34.558
37.699
40.841
43,982
47. 124
50.266
56.549
62.832
69.115
75.398
84.823
94.24
103.673
113.097
122.522
131 .947
141.372
157.080
172.788
188.496
204.204
219.911
235.619
Inches
0.0371
0.0495
0.0618
0.0742
0.0865
0.0989
0.1113
0.1237
0.1546
0.1855
0.2164
0.2474
0.2783
0.3092
0.3401
0. 37 11
0.4020
0.4329
0.4638
0.4947
0.5566
0.6184
0.6803
0.7421
0.8035
0.8658
0.9895
0.1132
1.2368
1.3606
1.4843
1.6079
1.7317
1.854 1
1.9790
2.2263
2.4737
2.7210
2.9685
3.339
3.7 11
4.082
4.453
4.824
5.195
5.566
6.184
6.803
7.421
8.040
8.658
9.276
Addendu
m,
Dedendum,
Whole
Whole
Depth
Depth, 1’
Millimeter Millimeters* Millimeter Millimeter
s
a
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.25
1.5
1.75
2
2.25
2.50
2.75
3.00
3.25
3.50
3.75
4.0
4.5
5.0
5.5
6
6.5
7
8
9
10
11
12
13
14
15
16
18
20
22
24
27
30
33
36
39
42
45
50
55
60
65
70
75
6.35
0.467
0.583
0.700
0.817
0.933
1.050
1.167
1.458
1.750
2.042
2.333
2.625
2.917
3.208
3.500
3.791
4.083
4.375
4.666
5.25
5.833
6.416
7.000
7.583
8.166
9.333
10.499
11.666
12.833
14.000
15. 166
16.332
17.499
18. 666
21.000
23.332
25.665
28.000
31 .498
35.000
38.498
41.998
45.497
48.997
52.497
58.330
64.163
69.996
75.829
81 .662
87.495
0.650
0.867
1.083
1.300
1.5 17
1.733
1.950
2.167
2.708
3.250
3.792
4.333
4.875
5.417
5.958
6.500
7.041
7.583
8.125
8.666
9.750
10.8331
1.9 1613
.000
14.083
15.166
17.333
19.499
21 .666
23.8332
6.00028
.166
30.332
32.499
34.666
39.000
43.332
47.665
52.000
58.498
65.000
71 .498
77.998
84.497
90.997
97.497
108.330
119.163
129.996
140.829
151 .662
162.495
S
0.647
0.863
1.079
1.294
1.510
1.726
1.94 1
2.157
2.697
3.236
3.774
4.314
4.853
5.392
5.932
6.471
7.010
7.550
8.089
8.628
9.707
10.785
11.864
12.942
14.021
15.099
17.256
19.413
21 .571
23.728
25.684
28.04 1
30. 198
32.355
34. 512
38.826
43. 142
47.454
51 .768
58.239
64.713
71.181
77.652
84. 123
90.594
97.065
107.855
118.635
Flying off the
job from the
two centres
due to sudden
movement of
the tool jerking
back of the tail
stock
(1) Splash guard
(2) Full enclosure guard
Inserting
blanks and
moving the
processed pertwithout
stopping
Spindle jaws, Mechanical
feeding device like that of
F.H.J. Safety fixture
*Dedendum and total depth when clearance = 0.1666
x module, or one-sixth module.
tTotal depth equivalent to American standard fulldepth teeth. (Clearance = 0.157 x module.)
Splash guard/Enclosure
guard mounted on rollers.
(a) Counter-wL falling
and bar flying thro’
turret head
(k) Splashing of
coolant
resulting in
slipping
hazards and
dermatitis
129.426
140.205
150.775
161 .775
Special Accidents in Turrets & Capstan Lathes:
(1) Tube guard
(2) Blank off hole
Special Accident in Multispindle Lathe:
(a) Collecting component Wire-mesh, spoon
while just parting off
276
CHAPTER 13— MACHINE SHOP MACHINERY AND EQUIPMENT
(b) Top parted off
component comes in
between tool and of
first spindle.
7.2
Sharpening tools properly
(a) Removing swan by
Brush, Magnetic
hand using rag to
sweep
clean excess oil while
it is running
Boring Machines Machine performing boring
functions-including vertical and horizontal boring
mills, jig borers, drilling machines, reamers and
honing machine.
-
A sleeve guard for spindle, telescopic grill guard
for tool or a combined chuck and drill guard can
be provided. Spinning of unclamped job and
subsequent breakable of tool and injury to the
operator can be eBminated by clamping if the job
is small or providing iron plate on the table when
the job is big.
(a) Contact with the spindle relescopic chuck
and drill bits
and spindle guard
Clamps or use of
L angle iron
(c) Being struck by a job
due to insecurely
clamped work
Clamps or use of
L angle iron
Extending flexible
guard, automatic
guard, fixed-bar type
guard or interlocked
guard
(f) Attempting to remove Education and
the nut from the
Training
machine arber by
applying power to the
machine
Varieties of guards have been developed for the
horizontal and vertical milling machine, from a
simple enclosure type of guard to the self
closing guard, in which the cutter is entirely
enclosed when the table is withdrawn and the
guard opens automatically as the table moves
forward for operation.
le) Sweepinq chips by hand Brush
MiNing Machines
Hazards involve are
contact with revolving cutters generally occurs in
removing chips and waste; flying chips; unsafe
operating practice such as tightening the arber
nut by using the power of the machine or
attempting to adjust the work of the tool while
the machine is in motion and working loose
clothing. Fixed guard, automatic guard and
interlocked guard of innumerable kinds are
available for thee, as described.
—
(c) Leaving the cutter
exposed after the job
has been withdrawn
(e) Slipping of spanner
Use of proper spanner
while adjusting,
tighten, loosening etc.
(d) Catching of hair or loose Cage type guard
sleeve in the revolving
spindle and bit
7.3
Permanent magnetic
plate fitted on bed
according to
connection
(d) Failure to draw the job Fixed guard
back to a safe
distance when loading
and unloading
Causes of injury in drilling operations are:
(b) Breaking ofa tool and
lunt it bit
(b) Failure to clamp the
work properly
—
Vertical milling machines: Segment
guard and enclosed guard may be
used according to the condition.
7.4
Horizontal & Vertical Bed Movement.
About 2/3 of all milling machine accidents occur
when operators unload and load, or make
adjustments, when running. Other causes of
injuries are:
Planning Machines Machine tools performing
planning operation include basic planer, shaper,
slotters, broacher and key seaters. Modern
machine tools are designed and built in such a
way that all the transmission parts are guarded
properly with built-in guards. Point of operation
guarding is to made according to operation.
—
a.
277
Hazards in Planers Struck by the moving
table or by material on the table; caught
between the table and the frame or bed of
the machine. In case of huge planning
machines a fall from the table or the bed, fall
—
CHAPTER 13- MACHINE SHOP MACHINERY AND EQUIPMENT
a.
between the uprights may be a serious
matter. Unsafe practices such as changing
stop dogs when the machine is in motion,
riding the table during the operation.
Hazards lie in handling material into or out
of machine and removing chips.
Accidents occur due to the following:
1.
2.
3.
Guard rail or barrier to close off any space
less than 457.2 mm between fixed part and
planner bed. Self adjusting table guard on
the sides of the planner are essential.
b.
4.
5.
6.
7.
8.
9.
Flying chips; flying
Hazards in Shapers
job if the work is not securely clamped;
attempting to adjust machine while it is in
motion; caught between ram and fixed
object and out injuries in removing chip.
Shaper can be provided with a combination
container for chips and transparent shield
for tool, a retriever to the limit of the stroke
of ran channel. The reversing dogs on the
planers and shapers should be covered. If
the planner bed travels within 457.2 mm of a
wall or fixed objects, there should be barrier
to prevent entrapping.
—
10.
11.
12.
13.
14.
15.
Breaches may be covered with transparent
cover and guarded by two-hand electric
interlocks.
7.5
16.
17.
18.
19.
Grinding Machines Internal grinding, external
or cylindrical grinding, surface grinding,
polishing, buffing, honing are classified under
this cadre.
—
20.
7.6
Wheel guard and eye shield can be fitted to
prevent the most common accident due to flying
of particles on tool grinders. Segment guard for
portable grinders. Wheel guard and enclosure
for surface grinders:
Proper Inspection and Storage:
(a)
(b)
(c)
278
Failure to use suitable protective
equipment like goggle face shield
etc.
Holding the work improperly.
No work rest or improperly adjusted
work nest.
Improper or no wheel guard.
Excessive wheel speed.
Cleaning, adjusting or gauging work
while the machine is in motion.
Side grinding
Using wrong type of wheel.
Bursting of wheels, due to
excessive tightening or damage in
transit.
Applying work too quickly to a cold
wheel.
Vibration due to improper balance.
Applying too heavy a cut.
Using a spindle with incorrect
diameter.
Threads on spindle tends to loosen
the nut as spindle revolves.
Wrong size of flanges or flanges of
unequal diameter.
Flanges with un-relieved centers.
Failure to use wheel washers.
Wheel out of balance.
Grinding too high above the centre
line of the wheel.
Incorrect dressing of the wheel.
“Ring” test by qualified person.
Proper storing in dry area.
Then speed test while installing.
CHAPTER 14- MANUFACTURING PROCESS
Chapter 14
MANUFACTURING
PROCESS
Section 2.0 Classification of
Manufacturing Processes
Section 1.0 Definition
Hobbing A method of making molds for the plastics
and die casting industries.
—
2.1
Infiltration
The process of filling the pores of a
sintered product with molten metal in order to decrease
porosity or to improve physical properties.
—
Interferometry
The science of measuring with light
waves, measuring to the millionth part of an inch
(approx. 25 mm). The small instrument is known as
optical flats.
—
Intraforming
A process in which metal is squeezed
at a pressure of about 300 tons (4000MP5) or less into
a die or mandrel to produce an internal configuration.
—
—
—
method
of
cold
working
Most metal products originate as an ingot casting
from one of the many ore-reducing or ore-refining
processes. Molten metal is poured into metal or
graphite molds to form ingots of convenient size
and shape for further processing.
Casting
Rolling
Crushing
Bending
Stretch Forming
Explosive Forming
Powder Metal Forming
Metal Spinning The operation of shaping thin metal
by pressing it against f form while rotating.
—
Extraction from Ore
Casting
Hot and Cold Working
Powder Metallurgy Forming
Plastic Moulding
Processes used primarily to change the shape of
metals include the following.
Ironing A name given to an operation for sizing and
thinning the walls of drawn cups.
Piercing
The
compression.
Processes used to change the shape of materials
by
Powder Metallurgy The art of producing commercial
products from metallic powders by pressure.
—
Forging
Drawing
Piercing
Shearing
Roll Forming
Magnetic Forming
Plastic Molding
Extruding
Squeezing
Swaging
Spinning
Torch Cutting
Electroforming
Electrohydraulic
Forming
In this group of processes, material is changed
into its primary form for some selected part.
Sometimes, the parts are suitably finished for
commercial use, as in metal spinning, cold rolling
of shafting, die casting, stretch forming of sheet
metal and drawing wire. Other times neither the
dimensions nor the surface finish are satisfactory
for the final product, and further work on the part
is necessary. It should be noted that the last
three processes, eleCtroforming, the forming of
powder metal parts and plastic moulding do not
originate as a casting. Electroformed parts are
produced by electrolytic deposition of metal onto
a conductive performed pattern. Metal is supplied
from the electrolyte and a bar of pure metal that
acts as an anode. Parts of controlled thickness,
having high pressure can be made by this
process. The method used in the production of
The operation of shaping thin metal by
Spinning
pressing it against a form while it is rotating.
—
Swaging A force in impact which causes the metal to
flow in some predetermined shape according to the
design of the dies.
—
Toughening
A form of tempering used to enhance
the toughness of a hardened steel where high hardness
is not particularly needed in service.
—
Ultra Sonic Impact Grinding
A means of cutting
shapes of all kinds by the rapid motion of abrasive
particles.
—
279
CHAPTER 14— MANUFACTURING PROCESS
powder metal products requires a heating
operation to assist in bonding the particles
together. Plastic are molded under heat and/or
pressure to conform to the configuration of a
mold. Explosive, electrohydraulic, and magnetic
forming are high-energy rate processes in which
parts are formed very rapidly by extremely high
pressures.
2.2
Chemical machining is done either attacking the
metal chemically or by using a reverse plating
process.
2.3
Polishing
Electroplating
Super finishing
Parke rizing
Processes used for machining parts to a fixed
dimension
Traditional machining, chip removal
Non-traditional machining
a.
Turning
Boring
Milling
b.
Shaping
Sewing
Robbing
Drilling
Broaching
Routing
Non-traditional machining process:
ultrasonic
Optical laser
Abrasive jet cutting
Electrical discharge
Electrochemical
Electro beam machining
Abrasive belt grinding
Honing
Metal Spraying
Anodizing
Barrel tumbling
Lapping
Inorganic coating
Sheradizing
In this group there are processes that cause little
change in dimension and result primarily in
finishing the surface. Other processes, such as
grinding, remove some metal and bring the part
to a pre-planned dimension in addition to giving it
a good finish. In the processes such as honing,
lapping and polishing it is a matter of removing
small scratches with little change in dimension.
Super finishing is also a surface improving
process that removes undesirable fragmented
metal, leaving a base of solid crystalline metal.
Plating and similar processes, used to obtain
corrosion-resisting surfaces or just to give a
better appearance, do not change dimensions
materially.
In manufacturing any product there are
usually a number of machining operations,
which may be classified as follows:
Planning
Reaming
Grinding
Process for obtaining a surface finish. Surface
finishing operations are used to insure a smooth
surface, great accuracy, aesthetic appearance, or
protective coating. Processes used are:
Electro-Arc
Chem-Milling
Plasma-Arc
machining
In these secondary operations, which are
necessary for many products requiring close
dimensional accuracy, metal is removed from the
parts in small chips. Such operations are
performed on machine tools which include the
various power-driven machines used for culling
metal. All of these operate on either a
reciprocating or a rotary-type principle: Either the
tool or the work reciprocates or rotates as
indicated. The planer is an example of
work
the
since
machine,
reciprocating
reciprocates past the tool, which is held in a
stationary position. In other machines, such as
the shaper, the work is stationary and the tool
reciprocates. Rotary machines are exemplified by
the lather, which has the work rotating and the
tool stationary. In the drill press it is the tool that
rotates.
2.4
Process used for joining parts of materials.
Products requiring the assembly of two or more
parts are usually joined by one of the following
processes:
Welding
Pressing
Soldering
Riveting
Brazing
Screw Fastening
Sintering
Adhesive joining
Welding is the fusion or uniting of metal parts by
heat and pressure. Soldering and brazing
operations are similar except that the parts are
joined by introducing a different metal between
the two in a molten state. Sintering applies to the
bonding of metallic particles by the application of
heat. Structural adhesives in the form of powder,
liquids, solids and tapes are widely used in the
joining of metals, wood glass cloth and plastic.
2.5
In ultrasonic machining, metal is removed by
abrasive grains which are carried in a liquid and
bombard the work surface at high velocity. The
velocity is generated by means of an ultrasonic
generator. For electrical discharge and electro
arc machining, special arcs are generated that
can be used to machine any conducting material.
The optical laser is a strong beam of photons that
can be used to generate extremely high
temperature and thus cut or weld metal.
Processes used to change the physical
properties. There are number of processes in
which the physical properties of he material are
changed by the application of an elevated
temperature or from rapid or repeated stressing
of the material. Processes in which properties are
changed include:
Heat Treatment
Cold Working
280
Hot Working
Shot Peening
CHAPTER 14
-
MANUFACTURING PROCESS
Heat treating includes a number of processes
that results in changing the properties and
structure of metals. Although both hot and cold
working are primarily processes for changing the
shape of metals, these processes have
considerable influence on both the structure and
the properties of the metal. Shot peening renders
many small parts, such as springs, resistant to
fatigue failure.
lubricant that stands up under such tremendous
pressures.
Dies must be hard and wear-resistant as well as
strong. They are made of children iron, hardened
alloy steel, cemented carbide and diamond.
3.4
Electro-Forming
Is one of the special
processes for forming metals. Parts are produced
by electrolytic deposition of metal upon a
conductive removable mold or matrix. The mold
established the sizes and surface smoothness of
the finished product. Metal is applied to the
conductive mold, from electrolytic solution in
which a bar of pure metal acts as an anode for
the plating current. It is particularly valuable for
fabricating thin walled parts requiring a high order
of accuracy. Internal surface finish and
complicated internal forms that are difficult to
cure or machine.
3.5
Explosive Forming
An excellent method of
utilizing energy at a high rate, since the gas
pressure and rate of detonation can be carefully
controlled. Both low and high explosives, known
as cartridge system, the expanding gas is
confined and pressure may build up to 7042
. High explosives which need to be
2
kg/cm
confined and which detonate with a high velocity
may attain pressures of up to 20 times that of
flow liquid set up intense shock waves that pass
through the medium between the change and the
work piece but decrease in intensity as the waves
spread over more areas.
3.6
Electroplating Electroplating is done on all the
common metals and even on many metal after
their surfaces have been prepared. The piece to
be plated is immersed in a water solution of salts
of the metal to be applied and made the cathode
in a direct current circuit. Anodes of the coating
metal replenish the solution when the current is
flowing and ions of metal are attracted to the
work piece to form the coating. The rate of
deposition and the properties of the plate such as
hardness, uniformity and porosity depend upon
getting a proper balance among the composition
of the plating solution, current density, agitation,
solution acidity and temperature.
3.7
Extrusion Many plastics are extruded into long
shapes by being forced through dies. Sometimes
this is done intermittently by a plunger in a
cylinder, but the common continuous method are
the material drops from a hopper into a heated
cylinder in which it is pushed along and out
through the opening in the die by screw.
Section 3.0 Processes
3.1
Brazing A group of welding operation in which
a non-ferrous filler metal melts at a temperature
below that of the metal joined but is heated above
425°C. The molten filler metal flows by capillarity
between the heated but unmelted adjacent or
overlapping joint members or is melted in place
between these members.
—
Filler metals are divided into two classes: copper
aNoys and silver alloys.
Copper alloyed with zinc, tin, nickel, phosphorous
or silver is brazed at 705°C to 175°C.
Silver alloyed with copper, zinc, tin, calcium,
manganese, nickel or phosphorous is brazed at
635°C to 843°C.
3.2
3.3
Blow Molding Is used primarily to produce tin
walled hollow containers from thermoplastic
resin. A cylinder of plastic materials, known as
parison, is extruded as rapidly as possible and
positioned between the jaws of a split mold. As
the mold is closed, it pinches off the parison and
the product is completed by air pressure forcing
the materials against the mold surface.
—
Cold Drawing
Hot rolled stack is descaled,
cleaned and prepared for drawing. A common
way of treating steel is
to immerse it in hot
sulphuric acid, rinse, coat with lime and bake.
The leading end of a piece is tapered for insertion
through the die. A piece is pulled though a hole
of a smaller size and emerges corresponding
reduced in size wire is pulled by being wound on
a drum as it comes out of the die. Rods, bars
and tubes are pulled in a straight line by
mechanical means. A mandrel is inserted in a
tube to control the size of the inside diameter.
—
Drawing pressure against a die must exceed the
yield strength of the work material and commonly
is as much as 7042 to 21126 kg/cm
2 for steel.
Steel is only to slide through a die coated by a
281
—
—
—
—
CHAPTER 14— MANUFACTURING PROCESS
open the die. The stock is moved to the next
station, and the cycle is repeated.
Many thermoplastic materials can be extruded
into tube, rod, film sheet and other shapes.
Reinforced thermosetting tube and rod are
formed by extruding reinforcing fiber soaked in
liquid resin and passing the extruded shape
slowly though a heated tube to allow it
polymerize.
e.
Forging
a.
A hot work piece is
Hammer Forging
placed on an anvil and struck repeatedly by a
hammer.
b.
Drop Forging
f.
—
—
—
Two half rolls are arranged
A piece of stock is placed between the rolls,
which in turn squeeze the stock in one set of
grooves. The stock transferred to a second
set of grooves, the roll turn again and so on
until the piece is finished. Bar stock may be
increased in length, reduce in diameter and
changes in section as desired.
Extrusion is rapid and more economical than
molding for many parts.
3.8
Roll Forging
on parallel shafts for roll forging. These roll
segments have one or more sets of grooves.
Iron foundry comprises of six
Foundries
basic sections:
—
1.
Melting and pouring
2.
Moulding
3.
Core-making, including sand
preparation
4.
Knock-out, including decoring and
sand reclamation
The operation of forming
parts hot on drop hammer with impression or
cavity dies. The products are known as drop
forging closed-die forging or impression die
forging. They are made from carbon and
alloy steels and alloy of aluminium copper,
magnesium and nickels, stock in the form of
the heated end of a bar, slug or individual
billet is placed in a cavity in the bottom half of
a forging die on the anvil of a drop hammer.
The upper half is attached to the hammer or
ram and fall on the stock which is made to
flow into and fill cavity.
c.
This is done in presses
Press Forging
rather than with hammer. The action is
relatively slow squeezing instead of pending
and penetrates deeply because it gives time
to flow. Dies may have less draft vibration
and noise are less and a press may have a
less bulk than a tons per square inch of
projected area on the parting plane have
been found to be 5-20 for brass, 10—20 for
aluminium, 15—30 for steel, 20-40 for
titanium.
d.
Also called hot reading and
machine forging, consist of applying
lengthwise pressure to a hot bar held
between grooved dies to enlarge some
section or sections, usually the end. The
work piece may have any original uniform
cross sections, but is mostly round and
maybe of steel, aluminium, copper, bronze or
other metal. A piece of hot stock is placed in
the cavity on one side of the die. The
machine is stripped, closes the two halves of
the die to grip the stock, pushes the punch
into upset the stock, retract the punch and
5.
Fettling, including inspection and
testing
6.
Pattern-Making
—
Upset Forging
—
3.9
Principal operation
Furnace, Kilns, Ovens
performed in furnaces, ovens and kilns.
—
a.
282
Furnace, smelting and reduction melting and
refining heat treating, brazing and soldering,
heating for hot working, boiler furnaces and
incinerators.
CHAPTER 14— MANUFACTURING PROCESS
b.
Kiln, cement kiln, lime kiln, ceramic kiln and
drying kilns.
c.
Oven, drying and caring, baking, decorating
and solvent evaporation.
The automatic controls that regulate fuel and
correct
and
ensure
the
air supply
temperature should be maintained in good
conditions,
be
these controls should
calibrated at frequent intervals.
d.
Mounting
Accident and breakages occur
when wheel are mounted on unsuitable
apparatus or spindle end of buffing
machines. The spindle should be of adequate
diameter but not be large as to expand the
center hole of the wheel; flanges should be
not less than one-third the diameter of the
wheel and made of mild steel or of similar
materials.
e.
Speed The maximum permissible operating
speed specified by the manufacturer shall not
be exceeded. A notice indicating the spindle
speed should be fitted to all grinding
machines and the wheel should be marked
with the maximum permissible speed and the
corresponding number of revolution for the
new wheel.
f.
Work Rest
Work rest of adequate
dimension and rigidly mounted should be
provided. They should be adjustable and kept
as close as possible to the wheel to prevent a
trap in which the work might be forced
against the wheel and break it or the
operator’s hand could be caught and injured.
3.10 Galvanizing A process by which zinc coating is
applied to a wide variety of steel product to
provide protection against corrosion.
—
Two basic method of galvanizing:
a
b
Hot dip-galvanizing dipping or passing the
steel product through a bath of molten zinc.
Cold electro galvanizing-process of providing
any metal with a zinc coating by means of an
electric current.
3.11 Grinding, Polishing
A process of finishing
various materials for either safety, operational or
aesthetic appearances. Many machine parts
undergo precision finishing to meet their
operational requirements. This process utilizes
high speed rotating wheels that are hazardous to
operators and the surrounding areas. The
following precautions shall be carefully followed:
—
—
—
—
Abrasive Wheel should be provided with
guards strong enough to contain the parts of
a bursting wheel. The grinding opening
should be as small as possible and an
adjustable nose piece maybe necessary.
The equipment for metal spraying
3.12 Metallizing
consist of a pistol-shaped spray gun (Schooping
gun) through which the metal, in the form of wire
is fed to a blowpipe flame which melt it, the
molten metal thus produced being sprayed by a
steam of compressed air surrounding the flame.
—
a.
A wheel may
Handling and Storing
become damaged or cracked during transit or
handling, moisture may attack the bonding
agent in phenolic resin wheel, ultimately
reducing their strength. Vitrified wheels
maybe sensitive to repeated temperature
variations; irregularly absorbed moisture may
throw the wheel out of balance. Wheels are
carefully handled at all stages and kept in an
orderly manner in a dry and protected place.
—
The heat source on the blowpipe is a fuel
gas/oxygen flame and the fuel gas maybe either
acetylene, propane or compressed town gas.
3.13 Magnetic Forming This is another example of
the direct conversion of electrical energy into
useful work. The process involved charging
voltage is supplied by a high voltage source into
a bank of capacitors connected in parallel. The
amount of energy stored can be varied by either
adding capacitors to the bank or by increasing
the voltage. The charging operation is very rapid
and when complete a high voltage switch triggers
the stored electrical energy through the coils
establishing a rapid high intensity magnetic field.
This field induced a current into the conductive
acts on the work piece.
—
b.
Checking for Crack A new wheel should
be checked to ensure that it is undamaged
and dry, most simply trapping with a worden
mallet.
c.
Testing
—
—
Before the new wheel is put into
service, it should be tested at full speed with
due precaution being observed. After wet
grinding, the wheel should be run idle to eject
the water otherwise the water may collect at
the bottom of the wheel and cause imbalance
which may result to bursting.
283
CHAPTER 14— MANUFACTURING PROCESS
of finished shapes to be made, they are first
rolled into such intermediate shapes as blooms,
billets or slabs. A bloom has a square cross
section with a minimum size of 150 mm x 150
mm. A billet is smaller than a bloom and may
have a square section from 38.1 mm up to the
size of a bloom. Slab maybe rolled from either
ingot or a bloom. They have a rectangular cross
sectional area with a minimum width of 250 mm
and a minimum thickness which maybe as much
as 380 mm. Plates skelp and thin strips are rolled
from slabs.
3.14 Plastic Processes The processes employed in
plastic technology are compression moulding,
transfer moulding, injection moulding, extrusion,
calendaring, blow moulding, film forming, thermal
forming vacuum forming, laminating and resin
technology processes.
—
The hazard in plastic processing are associated
with the use of machines. Moulding machines
have press platens or dies with locking forces of
many tonnes per square centimetres and these
should be adequately guarded to prevent
crushing injuries. Plastic processing machine
operate at high temperature and severe burn if
body come in contact with the hot metal.
Most primary rolling is done in either a two-high
reversing mill or a three-high reversing mill. The
piece passes through the roll which then stopped
reversed in direction and the operalion is
repeated. At frequent intervals the metal is turned
90 degrees on its side to keep the section
uniform and to refine the metal throughout. About
30 passes are required to reduce a large ingot
into a bloom. Grooves are provided on both the
upper and the lower rolls to accommodate the
various reductions in cross-sectional area. The
two high rolling is quite versatile, since it has a
wide range of adjustment as to size of pieces and
rates of reductions. It is limited by the length that
can be rolled and by the inertia forces which must
be overcome each time a reversal is made.
These are eliminated in the three-high mill.
Three-high mill is less expensive to make and
has a higher output than the reversing mill.
The process of pressing is used to
3.15 Presses
mould or cut many different materials. In
mechanical metal press it works on an
intermittent reciprocating system and so requires
a clutch.
—
Accident occurs when workers hand is between
the dies as they close either during an expected
stroke because for some reason the worker has
failed to remove his hand or during a repeat
stroke when the worker is feeling on with drawing
work between the dies.
3.16 Plasma-Arc In a plasma-torch, a gas is heated
by a tungsten arc to such a high temperature that
it becomes ionized and acts as a conductor of
electricity. The torch is generally designed so that
the gas is closely confined to the arc column
through a small orifice. This increases the
temperature of the plasma and concentrates its
energy on a small area of the work piece which
rapidly melts the metal.
—
Billets could be rolled to size in a large mill used
for blooms, but this is not usually done for
economic reasons. Frequently they are rolled
from bloom in a continuous billet mill consisting of
about eight rolling stands in a straight line. The
steel makes but one pass throughout the mill and
emerge with a final billet size approximately 50
mm x 50 mm which is the raw materials for many
final shaped as bars, tubes and forging.
Steel ingots that are not to be re
3.17 Rolling
melted and cast into molds are converted to
useful products in two steps;
—
a.
RoIling the steel into intermediate shapeblooms, billet and slabs
b.
Processing blooms, billets and slabs into
plate, sheets, structural shapes or foils
3.18 Riveting
Mechanical means of permanently
fastening parts together to rivet two parts, a rivet
is put through a hole and its head placed on an
anvil. A punch with a hollowed end mashes the
stem to close the rivet. Some rivets are hollowed
and their edges are curled outward.
—
The steel remains in ingots molds until the
solidifications are about to complete when the
molds are removed. While still hot, the ingots are
placed in gas-fired furnaces called soaking pits
where they attain or remain until they have
attained a uniform working temperature of about
1 200°C throughout. The ingots are then taken in
the rolling mill where, because of the large variety
Product requiring close tolerance may
3.19 Sizing
necessitate a final operation such as repressing
the part in a die similar to the one for compacting
it. Such sizing is a cold working operation that
improves surface hardness and smoothness as
well as dimension accuracy.
—
284
CHAPTER 14- MANUFACTURING PROCESS
3.20 Stretch Forming
In forming a large thin metal
involving symmetrical shape or double curve
bends, a metal stretch press can be used
effectively. A single die mounted on a ram is
placed between the slides that grip the metal
sheet. The die moves in a vertical direction and
the slides move horizontally large forces of 50 to
150 tons (0.5 to 1.3M) are provided for the die
slides. The process is a stretching one and
causes the sheet to be stressed above its elastic
limit while conforming to die shape. This
accompanied by a slight thinning of the sheet and
action is such that there is little spring back to the
metal once it is formed.
—
most cases the effect of the heating is complete
in a very short time. Furnaces for sintering may
either be by batch or continuous type.
3.22 Soldering —Uniting of two pieces of metal by
means of a different metal which is applied
between the two in a molten state. The metal for
this purpose is a low-melting alloy of lead and tin.
SOLDERING
Hard
I
Brazing
321 Sintering
Application of heat, which must be
kept at a temperature below the melting point of
the metal powder, in the production of
commercial products from metallic powders by
pressure or atomic forces, and resulting in the
bonding of fine particles together, thus improving
the strength and other properties of the finished
product. Products made by powder metallurgy
are frequently mixed with different metal powders
or contain non-metallic constituents to improve
the bonding qualities of the particles and
improved certain properties or characteristics of
the final product. Cobalt or other metal is
necessary in the bonding of tungsten carbide
particles, whereas graphite is added with bearingmetal powders to improve the lubricating qualities
of the finished bearing. Sintering is an operation
in which the particles are fused together in such a
way that the density is increased. During the
process grain boundaries are formed which is the
beginning or recrystallization. Plasticity is
increased, and better mechanical interlocking is
produced by building a fluid network. The
temperatures used in sintering are usually well
below the melting point of the principal powder
constituent but may vary over a wide range up to
a temperature just below the melting point Tests
have proved that there is usually an optimum
sintering temperature for a given set of
conditions.
Soft
I
Silver Soldering
Soldering Iron
Wiping
—
.
For most metals, sintering temperature can be
obtained in commercial furnaces, but for some
metals requiring high temperature, special
furnaces must be constructed. There is
considerable range in the sintering temperature,
but the following temperatures have proved
satisfactory: 1 095°C for iron, 1 180°C for
stainless steel, 870 for copper and 1 480°C for
tungsten carbide. Sintering times range from 20
to 40 minutes for the above listed metals. The
time element varies with different metals, but in
285
3.23 Thermo-Forming
Consists of heating a
thermo-plastic sheet until it softens and then
forcing it to conform to some mold either by
differential air pressure or mechanical means.
—
3.24 Ultrasonic Machining
A mechanical process
was designed to effectively machine hard brittle
materials. It removes materials by the use of
abrasive grains that are carried in a liquid
between the tool and the work and bombard the
work surface at high velocity.
3.25 Wire Drawing
—
Wire is made by cold drawing
hot rolled wire rod through one or more dies to
decrease its size and increase the physical
properties. The wire rod, about 6 mm in diameter,
is rolled from a single billet and cleaned in an
acid bath to remove scale, rust and coating. The
coating is applied to prevent oxidation, neutralize
any remaining acid and to act as a lubricant or a
coating to which a later applied lubricant may
cling.
—
3.26 Welding and Thermal Cutting
—
The three
common direct source of heat are:
a.
Flame produced by combustion of fuel gas
with air or oxygen.
b.
Electrical arc, stwck between an electrode
and a work piece or between two electrodes.
c.
Electrical resistance offered to passage of
current between two or more work piece.
Types of Welding:
1.
2.
3.
4.
5.
Gas Welding
ArcWelding
Atomic Hydrogen Welding Welding
Electro-Beam Welding
Electro-Slug Welding
CHAPTER 14— MANUFACTURING PROCESS
6.
7.
8.
9.
10.
11.
12.
13.
14.
Flash Welding
Friction Welding
Laser Welding and Drilling
Metal Spraying
Plasma-Arc Welding
Resistance Welding
Spark Erosion Machining
Stud Welding
Thermal Welding
1.
The process in which
Gas Welding
gases are used in combination to obtain
a hot flame. Commonly used are
acetylene, natural gas, hydrogen in
combination with oxygen. The maximum
temperature developed for oxy-hydrogen
welding is 1 965°C for Oxy-acetylene
Welding is 3 440°C.
6.
A process
Electric-Arc Welding
wherein the metal is heated to its liquid
state and allowed to solidify thereby
making the joint. Heating is achieved
through an electric arc between an
electrode and the work pieces. The high
current low voltage power source can
either be an AC or DC.
7.
A
Friction Welding (Cold Welding)
in
technique
welding
purely mechanical
which one component remains stationary
while the other is rotated against it under
pressure. Heat is generated by friction
and at forging temperature the rotation
ceases. A forging pressure then affect
the weld.
welding
arc
electric
plain
The
(unshielded) as originally practiced
produced brittle and weak weld joints.
This is due to contamination from the
surrounding air of the weld metal while
they are at their liquid state. In 1972, the
flux covered electrodes was developed
which greatly improved the quality of
weld joints. This development rapidly
revolutionized the electric arc welding
process and was then called “Shielded
Metal Arc Welding”.
8.
Laser
Laser Welding and Drilling
beams are used for these purposes in
requiring
application
industrial
exceptionally high precision.
9.
Wire or powder from
Metal Spraying
the nozzle of a spraying gun is fused by a
gas flame, arc or plasma-jet, and the
molten particles are projected in the form
of a spray by means of compressed air or
gas. It is often necessary for articles to
be shot blasted or pickled before they are
sprayed.
2.
5.
—
Today, shielded Arc Welding is the most
widely used welding process in various
industries. A separate article will be
devoted for this process.
An arc
Atomic Hydrogen Welding
struck between two tungsten electrodes
into which a jet of hydrogen is directed.
4.
A work piece
Electro-Beam Welding
contained in an executed chamber is
bombarded by a beam of electrons from
an electron gun at voltages between 0.5
KV and 100 Ky. The energy of the
electrons is transformed into heat on
striking the work piece.
—
The
Flash Welding (Butt Welding)
parts to be welded are
connected to a low voltage high current
source. When the end of the components
are brought into a contact, a large current
flows causing flashing to occur and
bringing the end of the components to
welding temperature.
—
two metal
—
3.
Electro-SIug Welding The work piece
are usually set vertically, with a gap
between them and copper plates or
shoes are placed one or both sides of the
joint to form a bath at the bottom of which
an arc is established under a flux lager
between one or more continuously fed
electrode wires and a metal plate.
—
—
—
In all these
10. Plasma-Arc Welding
processes the heat source is an arc
formed at a relatively small orifice
through which steam of air, argon,
helium, nitrogen or mixture of these
gases flow. The arc “plasma” is formed
into a jet by the gas pressure and
continue as a flame beyond the nozzle.
—
—
—
11. Resistance Welding A high current at
through
two
flows
voltage
low
components from electrodes. The heat
generated at the interface between the
components brings them to welding
temperatures. During the passage of the
—
286
CHAPTER 14- MANUFACTURING PROCESS
current, pressure by
produces a forge weld.
the
electrodes
12. Spark Erosion Machining
In this
technique metal is removed from the
piece to be machined by the action of
electric discharges between the piece
and an electrode immersed in electrolyte
oil.
—
the atmosphere that normally results to inferior
quality
weld joints.
Shielding
can
be
accomplished by various means such as inert
gases, welding fluxes but the most common is by
the use of readily available coated electrodes.
Refer to the illustrative drawing, Fig. 14.4.1
below:
13. Stud Welding An arc is struck between
the components to be joined and raised
the temperature of the ends of the
components to melting point. The
components are then automatically
pressed together and welded.
—
14. Thermit Welding
A mixture of
aluminum powder and a metal oxide
powder is ignited by a special powder in
a crucible. The oxide is reduced to metal
with the evolution of intense heat, the
crucible is tapped and molten metal flow
into the joint to melt the ends of the work
piece and form the weld.
—
With the use of coated electrodes, shielding is
accomplished by the evolution of shielding inert
gases during the welding process which prevent
air from reaching with the still molten weld metal.
Additionally, heavy slag is formed on the weld
bead which slows the rate of cooling thereby
allowing gases to escape and the slag particles to
rise. It also reduces cooling resistance and allows
more time for all the necessary chemical
reactions to take place in the weld metal.
3.27 Welding Processes
Welding 1
rP
ocesses
Plastic
Fusion
I
I
Forging
Electric Resistance
Gas
1. spot
2. projection
3. seam
4. butt
5. flash
6. percussion
Machine
1. Hammer
2. Rolls
Chemical
Reaction
1. thermit
It is also through these electrode coatings that
make welding with alternating current a
satisfactory operation. For a 60 Hertz AC, the arc
goes out 120 times a second thereby making arc
stability a major problem. With potassium
compounds or other similar additives in the
coating, the gases at the arc will remain ionized
during current reversal thereby maintaining a
stable arc.
1. oxyacetylene
2. oxyhydrogen
3. other combination
I
Manual
Sledge
Electric
Arc
I
Shielded
Carbon
1. Tungsten
Arc with
hydrogen
or argon
Metal
1. Bare
2. Fluxed
3. Covered
Other special welding electrodes contain
relatively large amount of iron powder that melt
together with the electrode core thereby
increasing weld metal deposition rate.
Section 4.0 Shielded Metal Arc Welding
4.1
Fig. 14.4.1
Schematic representation of the shielded metal arc welding.
Welding Process and Electrodes
As previously discussed, this is a development of
the early electric arc welding. The main
improvement is the introduction of shielding for
the molten weld metal against contamination from
287
For welding mild steel and low alloy steels, the
weld metal must match the metallurgy of the base
metal. The selection of the right electrode,
therefore, shall be given a very thorough
consideration. The American Welding Society
(AWS) and the American Society for Testing
CHAPTER 14- MANUFACTURING PROCESS
a
established
jointly
(ASTM)
Materials
a
using
electrodes
most
of
standardized coding
prefix “E” followed by four or five number system.
This is illustrated below.
EXXXXX
TfL
e.
This is a common weld defect.
Inclusion
Slags or foreign materials are trapped inside
the weld metal. These are normally due to
poor welding process and dirty work pieces.
f.
These are cuts between
Weld Undercuts
the weld metal and the base metal normally
—
due to excessive welding current. Refer to
Figure 14.4.2
Welding technique variables such
as current supply and application
Welding position number,
1 all positions can be used, flat,
horizontal, vertical or over
head
2 Flat and Horizontal fillet
3—Flat only
—
4.3
Testing and Quality Control
—
Welded joints can either be tested destructively
or non-destructively.
—
4.4
Materials can be randomly tested by actual
destruction of a work piece for examination. By
this process the particular work piece cannot be
anymore used. The following are types of
destructive testing:
Approximate Tensile strength in
kips
60 —60 000 psi
70 —70 000 psi
100—100,000 psi
4.2
Destructive Testing
Refer to Table 14.4.1 for various Electrode
Classification. After the above number series,
additional suffix maybe added to denote
electrode composition. Refer to Table 14.4.2
a.
A test specimen is cut-out
Tensile Test
from the work piece and stretched to failure.
Ultimate strength, yield point and percent
elongation can be determined.
Common Weld Defects
b.
Bending Test A test specimen is cut out
from the work piece and bended 90° to 180°.
This will determine cracking tendency and
joint ductility.
c.
The weld joint is cut by
Sectioning
hacksaw along the centreline of the weld to
allow visual examination of the weld.
a.
b.
Lack of Penetration The root pass did not
adequately fuse the adjoining base metals.
This is normally caused by the base metals
did not reach fusion temperature, fast
welding rate or too large an electrode used.
—
This normally occur at the
Weld Cracks
weld heat affected zone (HAZ) due to brittle
weldments associated with stresses. This is
common in welding molybdenum and
chromium alloys and thick weldments. This
can be minimized by pre-heating and
corrected by either stress relieving or
annealing.
—
—
—
—
4.5
Non Destructive Testing (NDT)
This is a process wherein weld examination is
done without destroying the material. Random or
complete examination of all welds can be done
and the material can still be used.
a.
c.
These are small holes through
Pinholes
the weldments normally caused by gas
bubbles escaping through the molten weld
metal while cooling. This is commonly due to
moisture loaded electrodes or dirty/moist
base metals.
d.
These are gas bubbles or minute
impurities trapped in the weldment normally
due to dirty or moist electrode or
contaminated base metals.
—
Porosity
—
288
This can be
Dye Penetrant Examination
determine surface cracks and porosities
which may not be readily seen. This is done
by thoroughly cleaning with solvents the weld
joint and spraying the surface with a
penetrating dye, normally red. Allow the dye
to penetrate for about one minute and
thoroughly wipe it off the surface and
followed with a gentle spray of a developer,
normally white. The whole surface will
become white except in areas that previously
absorbed the dye wherein the defect will be
revealed.
—
CHAPTER
14—
MANUFACTURING PROCESS
Table 14.4.1 Electrode Classification
Class No.
Work
Position
Current
Supply
Arc
Effect
Penetration
All Position, Deep Penetrating
EXX1 0
All
EXX 11
All
DC
+
AC
(DC i
V
Basic Application
— Good
Properties
Designed to produce good mechanical properties consistent with
jood radiographic inspection quality. Application is usually structural
vhere multi pass welding is employed, such as ship building, bridges,
buildings, piping and pressure vessels.
Digging
Deep
Mild
Medium
Designed to do the work of XX 10, but to employ an AC current.
Slightly higher tensile and yield strength.
Production Welding
—
EXX 12
EXX 24
All
DC
AC
—
AC
(DC
H.F.
F.
Mild
Mild
Medium
Light
All Position
EXX 13
All
AC
(DC -)
All
AC
‘DC
Soft
Soft
n iron powder type electrode ideal for fillet welds. The iron powder in
he electrode coating assists in increasing the deposit rate over the
12 class. Electrode can be used in drag technique with ease of
handling and good weld appearance. Requires better fit-up than 12,
but is of similar application, although limited as to position.
Light Penetrating
Medium
Designed for light metal work, but now used widely as an electrode
having light penetration. Frequently used in vertical down welding,
yen though it produces a flat bed. Particularly well designed for use
iith low voltage AC transformers.
Medium
n iron powder electrode designed to do the work of 13 with
ncreased deposit rate, although 14 has lower deposition rates than
4 and 27. In the fixed position, 13 and 14 have similar welding
peeds. Has improved weld appearance and ease of welding in drag
echnique.
-___________________
EXX 14
Especially recommended for single pass, high speed, high current,
horizontal fillet welds. It is characteris-tically easy to handle and
useful in cases of poor fit-up, both groove and fillet, where a wide
range of currents is used. Class 12 has reduced penetration but can
meet radiographic standards with single pass welds.
‘
Low Hydrogen
Difficult to Weld
Offers exceptional physical properties and best X-ray quality. A ‘low
hydrogen” electrode for difficult to weld materials such as high carbon
r low alloy steel. Also, free machining, high sulphur bearing, steel
and armor plate. Frequently pre- and post heating may be eliminated
r reduced by using low hydrogen rod. The rod coating cannot
perform properly with included moisture. Electrode should be heated
before use as recommended by the manufacturer, or stored in a
oisture-free area.
EXX 15
All
DC
+
Mild
Medium
EXX 16
All
AC
+
DC
Mild
Medium
upply.
EXX 18
H.F.- F
AC
DC
Mild
Medium
\ 30% iron powder titanis type electrode. A rod similar to 15 with a
higher deposition rate but an improved weld appearance. Offers
better slag removal and higher usable current than the E6016 type.
E)(X25
H.F.
DC
—
(AC)
Mild
Medium
\ 50% iron powder lime type electrode. This one yields the highest
leposition rates of the low hydrogen group. The coating also
produces an easy to maintain are with a smooth, wide bead; can only
,e used in the flat position.
-
F
, rod similar to 15 designed to be used with AC and DC
+
current
Deep Groove Heavy Sections
EXX2O
H•F
EXX27
H.F.
EXX3O
F
-
-
F
DC
—
AC
F
DC —
AC
DC—
A
Medium
Deep
. high production electrode designed for heavy sections, such as
pressure vessels, heavy machines bases, and structural parts; in flat
rr horizontal fillet position. The weld has good quality and is
requently used where deep fillet techniques are required.
Mild
Medium
rvhen this high iron powder electrode is used in the drag technique, it
s 50% faster than the 20 electrode. It is primarily a downward deep
troove rod, well suited for heavy sections. Second only to 24 in
velding speed, but with properties superior to it. Both are equally
asy to handle.
Mild
Medium
apable of higher deposition rates than 20. Designed for welding of
heavy plate in the flat position and good in deep groove welding. Has
less fluid slag than 20.
Mild
Current supply in parenthesis, as (C +), indicates that, for production
welding, some sacrifice in advantages must be made using the
designated supply.
H.F.
F.
289
=
=
Horizontal Fillet Position
Flat Position
CHAPTER
14-
MANUFACTURING PROCESS
Table 14.4.2
Electrode Composition
Class
No.
Comp.
Suffix
Carbon
Molybdenum
10
11
15
16
20
Al
Al
Al
Al
Al
Silicon
MOLYBDENUM_STEEL_ELECTRODES
0.40
0.35—0.60
0.40
0.35 0.60
0.45—0.90
0.60@
0.40—0.65
0.10
0.45—0.90
0.60@
0.40
0.35— 0.60
CHROMIUM MOLYBDENUM_STEEL_ELECTRODES
CARBON
XX
XX
XX
XX
XX
Chromium Manganese
Sulfur
Nickel
—
—
0.04
-
10
11
13
15
16
Bl
Bl
Bi
Bi
Bl
0.10
10
11
13
15
16
B2
B2
B2
B2
B2
0.10
10
11
13
15
B3
B3
B3
B3
15
16
15
16
Cl
Cl
C2
C2
0.35—0.60
0.40
0.04
0.45—0.90
0.60@
0.04
0.35—0.60
0.40
0.04
0.90
0.60@
0.04
0.60
0.60
0.45—0.90
NICKEL STEEL ELECTRODES
0.60
0.40—0.65
0.40—0.65
0.40—0.65
1.00—1.50
0.45
0.35
0.12
0.90
—
1.20
2.00
—
—
—
0.04
2.50
0.12
0.12
0.10
0.10
0.90
0.60@
0.04
2.00
2.75
3.00
3.75
@ The silicon content may be 1.00 maximum if the carbon content is restricted to 0.06 maximum.
CAUTION:
It is important that this electrode selection procedure not be considered a final authority instead of
a series of actual weld trials or field experience. In cases of production welding, it is most
important that welding procedures or specifications be produced through experimentation.
Success and failure in high speed welding may still be in the proper selection of such variables as
amperage, voltage, speed of travel, electrode angle, welding technique, joint preparation, preheat,
inter pass temperature, post heat treatment, etc.
290
CHAPTER 14— MANUFACTURING PROCESS
b.
c.
d.
e.
Hardness Testing
This is a method of
determining the hardness of the weld more
particularly the heat affected zone. The
hardness will determine the cracking
tendency of weld joints. A 220 Brinell
Hardness Number (BHN) is normally
acceptable for common mild steel and low
alloy steels.
4.6
Section 5.0 Safety Precautions
5.1
Processes which emit fumes, mist, toxic vapor,
dust shall be provided with adequate exhaust
ventilation or proper enclosure.
5.2
Protective clothing, eye, nose, feet and hand
protection shall be used when exposed to hazard
such as toxic substances, radiation, hot and
corrosive substances.
5.3
Automatic control that regulate fuel and air supply
should be maintained in good condition to ensure
the correct temperature for the process.
5.5
Substitution of toxic substances to non-toxic
substances in any quantity process is possible.
5.4
Sources of dangerous
acoustically enclosed.
5.6
Rest rooms shall be provided with
ventilation and facilities.
5.7
Pipe lines or hoses shall be properly color coded.
This needs a trained technician to safely
handle and operate the radio isotope.
5.8
X-ray Examination
Essentially the same
with radiographic examination except only on
the source of radiation. This utilizes electricity
powered X-ray machine that generate
ionizing radiation.
Uninsulated hot pipelines or ducts shall be
provided with guards or insulated at portions
adjacent to passage ways for personnel
protection.
5.9
Moving machine parts shall be provided with
adequate protective guards.
Magnetic Particle Testing Uses electrical
current to create a magnetic field in a
specimen with the magnetic particles (iron
powder) indicating where the field is broken
by discontinuities such as cracks in the
material.
Applicable
to
ferromagnetic
materials only.
—
Radiographic Examination This employs
radioactive isotopes such as Cobalt-60,
lridium-192, Thulium-170 or Cesium-137 and
radiographic films. The internal or external
properties of the work piece can be depicted
on the film by the passage of radiation
through the work piece. This examination can
reveal cracks, porosities, inclusions, lack of
penetration and other defects. With the film, a
permanent record of the joint can be kept.
Areas that need repairs can likewise be
pinpointed.
-
—
Also needs a trained technician to safely
handle and operate the machine.
f.
pressurized piping’s and vessels, the final test
should be by hydro testing at a minimum
pressure of 1.5 times the design pressure plus
corrections for higher temperature operations.
—
Ultrasonic Examination
This utilizes
ultrasounds that penetrate most common
materials. The time of rebound of ultrasounds
from the probe which is pressed on one side
of the material to the other side or any
discontinuity is converted to unit of linear
measure.
This
method
can
detect
laminations, cracks and inclusions. This
needs an expert to evaluate the findings.
—
Final Test of Completed Work
The completed work is normally tested for
soundness by actual test loading. Particularly for
291
noise
should
be
proper
5.10 Welders must wear protective clothing, welding
masks and gloves.
5.11 Operations involving radiations shall be properly
identified and barricaded. Only authorized
technicians shall handle these equipment.
Section 6.0 Pollution Control
6.1
Air Pollution Control Equipment
a.
To
promote
clean
a
environment,
manufacturing process or installation whose
operation results in the emission of
contaminants must be provided with
appropriate air pollution control equipment.
CHAPTER 14- MANUFACTURING PROCESS
b.
1.
2.
3.
c.
constituents of a gas stream can be
removed or covered.
Air pollution control equipment for collecting
particulate matter (smoke, dust, fumes, mists,
etc.) emission are:
used for collecting
Inertial separators
medium and coarse size particulates.
The louver type collector is effective in
collecting dry above microns (p) in size
while the multi-baffle type is used in the
collection of mists.
3.
Afterburners combustion converts the
combustible constituents of a gas stream
into carbon and water.
4.
Vapor Condensers by extracting heat
vapor
pressure,
increasing
or
condensation is achieved.
—
d.
the tangential
Centrifugal separators
inflow tube or cyclone separators are
normally suitable for medium size (15 to
40 i) and coarse size particulates while
the axial flow inversion type or multiplecyclone separators are effective in
collecting particulates in the 5 to 15 p
range.
—
Rinsing or wet collection device
depending on the particular design, some
are capable for collecting particulates in
the sub-micron range. These devices
include spray-type, cyclone-type, orificetype, mechanical venture-type, jet-type,
and packed tower scrubbers.
have a high
Filtration devices
collection efficiency for sub-micron size
particulates. Panel filters are usually
used in filtering small volumes of
contaminated air while fabric filters can
handle large volumes of contaminated
air.
5.
Electrostatic precipitators suitable for
the collection of a wide variety of dust
and fumes.
6.
used as
Gravitational precipitators
and
coarse
remove
pre-cleaners to
and
protect
to
particulates
abrasive
augment the main dust collectors.
1.
Pollution is the downgrading of water
quality by sewage or other wastes to the
point where it unreasonably affects water
use for domestic, industrial, agricultural,
navigational or other beneficial uses. It is
therefore the concern of any citizen or
management to prevent water pollution to
existing streams or rivers. In order to
comply with the government effluent
standards for waste water the following
waste water treatment processes are
briefly discussed.
2.
Clarifying waste water is the process of
removing turbidity, sediment and floating
materials. It is the first step in treatment
since these impurities are highly
objectionable and interfere with any
subsequent treatment. Clarifiers are
sized on the basis of settling rate (area)
and detention time (volume). Pre
treatment ahead of sedimentation may
include screening and communiting,
degritting as well as grease and scum
removal.
3.
Coagulation is the gathering together of
finely divided or colloidal suspended
matter into larger particles. In this way
coagulating agents speed up the settling
of suspended matter and make it
possible to remove those small solids not
touched by conventional sedimentation.
4.
Flocculation is the agglomeration of finely
divided suspended matter and floc
caused by gently stirring or agitating the
waste water. The resulting increase on
particles size increases the settling rate
and improves suspended solids removal
by providing more efficient contact
between suspended solids, dissolved
impurities and chemical coagulants.
—
—
—
Air pollution control equipment for the
collection of a wide gaseous and vapor
emissions are:
1.
Adsorption Equipment the absorbent
selectively capture or remove gases or
liquids from dirty gas streams even at
very small concentrations.
2.
by using
Absorption Equipment
or more
one
selective liquids solvents,
—
—
292
—
Water Pollution
—
4.
—
CHAPTER 14- MANUFACTURING PROCESS
5.
6.
7.
Floatation is basically sedimentation in
reverse to remove floatable materials and
solids with a specific gravity so close to
water that they settle very slowly or not at
all. The principle of air floatation is based
on the fact that when the pressure on a
liquid is reduced, dissolved gasses are
released as extremely fine bubbles.
These bubbles attach themselves to any
suspended matter present and rapidly
float them to the surface where they
concentrate and can be removed by
skimming.
Gravity separation is used to remove
liquid pollutants that are insoluble in
water such as petroleum oils and the
cutting and coolant oils used in metalfinishing operations. Most have specific
gravity lower than water and will rise
rather than settle.
Granular activated carbon has long been
used in filtering equipment to remove
color and turbidity and improve the taste
of water by removing residual chlorine.
This same material is extremely effective
in absorbing organic contaminations from
waste water measured in terms of BOD,
COD, color, odor, optical density or other
analytical techniques.
8.
Biological filters commonly called trickling
filters are basically a pile of rocks over
which sewage or industrial waste slowly
trickles. The rock simply provides surface
on which microbes cling and grow as
they feed on the organic matter.
9.
Activated sludge is the process by which
masses on settle able solid formed by
simply aerating waste water containing
biologically degradable compounds in the
presence of microbes. The settle able
solids, called activated sludge consist of
bacterial fungi, protozoa, rotifiers and
nematodes are responsible for stabilizing
the organic matter and forming the floc.
10. Anaerobic digestion is widely used to
stabilize concentrated organic solids
removed from settling tanks, biological
filters and activated sludge plants. The
waste is mixed with large quantities of
microbes and oxygen is excluded. Under
these conditions highly specialized
293
bacteria grow, which convert the organics
into carbon dioxide and methane gas.
e.
Chemicals and chemical processes play a
basic role in waste water treatment:
1.
Adsorption using granulated activated
carbon is a reliable and effective way of
removing organic impurities found in
most water supplies. Activated carbon
adsorbers can be used after conventional
filtration of suspended matter or installed
as a combination filtration adsorption
unite.
2.
Coagulation is the process of adding
chemicals to waste water to produce a
flocculent precipitate that will remove fine
suspended
matter
and
colloidal
substances by adsorption or mechanical
entrainment.
3.
Dialysis
a practical toll for recovering
chemicals from process waste.
4.
Electra dialysis reduces the dissolved
solids content of water. Main application
is converting brackish water (1 000 to 10
000 ppm) to supply that is suitable for
potable use (below 500).
5.
Ion exchange is a versatile process that
keeps extending its range of service. In
waste water treatment it is used to
remove or recover anions and cations
depending on whether or not they are
valuable, undesirable or both.
6.
Neutralization of waste water is
frequently needed to keep pH in the
range of 6 to 8 required by most water
quality criteria.
7.
Oxidation reduction and precipitation
system are widely applied for the
treatment of plating wastes.
8.
Sludge handling and disposal is a final
step from waste water treatment plants.
9.
Sludge concentrators are mainly used
to thicken sludge from secondary
clarifiers or mixtures of sludge from both
primary and secondary treatment units.
—
—
10. Digestion under anaerobic conditions
makes sludge solid easier to dewater and
CHAPTER 14- MANUFACTURING PROCESS
convert parts of the inorganic matter to
gaseous end products. Sludge pumped
into an enclosed air tight vessel where
the solids decompose rapidly.
Section 7.0 Anti-Pollution for
Manufacturing Processes
7.1
All machineries/equipment used in manufacturing
processes whose operation results in dust,
gaseous and/or odor emissions should be
provided with appropriate air pollution control
facilities.
7.2
Manufacturing processes resulting in the
discharge of waste water should be provided with
appropriate waste water treatment facilities.
11. Dewatering is handled by drying beds,
lagoons, filters, and centrifugal.
12. Vacuum filtration is the most widely
used method of mechanical sludge
dewatering. Sludge is sucked by a
vacuum against a revolving drum partially
submerged in a vat or slurry tank.
13. Gravity filter consists of two cells
operating at atmospheric pressure.
These cells are formed by a fine-mesh
nylon filter cloth continuously travelling
over front and rear guide wheels. The
filter cloth is rotated by a drive roll and
sprocket assembly which also separates
the cells.
294
I
CHAPTER 15— FUELS AND LUBRICANTS
Chapter 15
FUELS AND LUBRICANTS
Section 1.0 Fuels
Classifications. There are three general types of fuel,
solid, including coal, coke, peat, briquets, wood,
charcoal, and waste products.
basis. The higher-rank coals are classified
according to fixed carbon on a dry basis; the
lower-rank coals, according to BTU.
2.3
Classification by Grade. The standard for
classification of coal by grade provides a symbol
designation system indicating size, BTU content,
ash, ash-softening temperature, and sulfur
content of coals. The size designation is given
first in accordance with the standard screen
analysis method followed by calorific value
(expressed in hundreds of BTU per pound to the
nearest hundred), and symbols representing
ash, ash-softening temperature, and sulfur, in
accordance with Table 15.2.1.2.
2.4
Burners for Pulverized Coal. Figure 15.2.2
shows schematically the basic methods of
feeding pulverized coal and air to furnaces. The
function of any burner is to supply coal and air in
such a manner as to obtain (1) complete
combustion
within
the
furnace,
thereby
minimizing carbon losses and utilizing the heatabsorbing surface most effectively, (2) adequate
mixing of the coal and air, (3) stable ignition to
prevent furnace
pulsations,
(4)
uniform
distribution of temperature and composition of
the gases leaving the furnace, (5) minimum slag
and ash deposits on boiler or secondary heating
surfaces, and (6) sufficient flexibility to burn a
range of quality coal.
Liquid, including petroleum and its derivatives,
synthetic liquid fuels manufactured from natural gas
and coal, shale oil, coal by-products (including tars
and light oil), and alcohols.
Gaseous, including natural gas, manufactured
industrial by-product gases, and the propane
butane or liquefied petroleum (LP) gases that
stored and delivered as liquids under pressure
used in gaseous form.
and
and
are
but
Section 2.0 Solid Fuels
2.1
2.2
Coal Classification. Three methods of
classifying coals have been adopted as
standard in the United States as the result of a
10-year study begun in 1927 by a large group of
specialists from the United States and Canada.
These classifications are: by rank (degree of
metamorphism, or progressive alteration, in the
natural series from lignite to anthracite); by
grade (quality determined by size designation,
calorific value, ash, ash-softening temperature,
and sulfur); and by type or variety (determined
by nature of the original plant material and
subsequent alteration thereof). Other methods
of coal classification are by use or suitability for
specific purposes or types of combustion
equipment, and by various trade systems set up
to meet particular conditions in a given area or
time. Examples of the use or special purpose
type of classification are given in two or other
standards that have been adopted in this
country. One of these classifies coal by ash
content and the other, a standard for gas and
cooking coals, classified by use.
Vertical firing, although an early method, still is
used extensively, but with all the secondary air
admitted around the burner nozzle so that it
mixes quickly with the coal primary air mixture
from the burner nozzle.
Classification by Rank. Probably the most
universally applicable method of classification is
by rank, in which coals are arranged according
to fixed carbon content and calorific value, in
BTU, calculated on the mineral-matter-free
295
CHAPTER 15— FUELS AND LUBRICANTS
Horizontal firing, employs a turbulent burner,
which consists of a circular nozzle within a
housing provided with adjustable valves, the unit
being located in the front or rear wall. The
primary air and coal are fed to the nozzle, in
which the mixture is given a rotary motion by
narrow, spiral vanes. The secondary air enters
the outer housing through the adjustable vanes,
which provide rotary motion at an angle different
from that of the primary air and coal, the
meeting of the primary-air coal mixture at the
periphery of the nozzle, creates a high degree of
turbulence. This type of burner is suited to high
capacity and dry bottom furnaces.
Table 15.2.1.1 Classification of Coals by Rank*
(FC
= fixed carbon; VM =
volatile matter. Btu
British thermal units)
Limits of Fixed Csrbori or
Class
I. Anthracitic
Group
1. Meta-anthracite
2. Anthracite
3. Semi-anthracite
II. Bituminous f
1. Low-volatile
bituminous coal
2. Medium-volatile
bituminous coal
3. High-volatile A
bituminous coal
4. High-volatile B
bituminous coal
5. High-volatile C
bituminous
Ill. Subbituminous
1. Sub-bituminous
A coal
2. Sub-bituminous
B coal
3. Sub-bituminous
C coal
IV. Ligriitic
1. Lignite
2. Brown coal
Btiu (Mineral-matter-
I Ph
R equisleysica
Dry FC, 98% or more
(dry) VM, 2% or less)
Dry FC, 92% or more
and less than 98% (dry
VM, 8% or less, and more
than 2%
Non-agglomeratingt
Dry FC, 86% or more,
and less than 92% (dry
VM, 14% or less, and
more than 8%
Dry FC, 78% or more
and less than 68% (dry
VM, 22% or less, and
more than 14%
Dry FC, 69% or more
and less than 78% (dry
VM, 31% or less, and
more than 22%
Dry FC, less than 69%
(dry VM, more than 31%),
and moist § Stu, 14 000
Moist § Btu, 13 000 or
more, and less than 14
000
Moist Btu, 11 000 or more
and less than 13 000
Moist Btu, 11 000 or
more, and less than 13
000
Moist Btu, 9500 or more,
and less than 11 000
Moist Btu, 8300 or more,
and less than 9500
Moist Btu, loss than 8300
Moist Btu, less than 8300
Corner or tangential firing is characterized by
burners located in each corner of the furnace
and directed tangent to a horizontal, imaginary
circle in the middle of the furnace, thereby
making the furnace the burner in effect, since
turbulence and intensive mixing occur where the
streams meet. The coal and primary air enter
through rectangular or square coal nozzles;
secondary air is supplied partly around the
nozzles and partly through ports above and
below them. Dampers proportion the secondary
air to the various sections. The relative velocities
of gas and fuel produce a scrubbing action that
promotes the transport of oxygen to the fuel,
through the film of combustion products around
the particles. Further, the tangential motion of
the gases produces a vortex, which effectively
lengthens the time that the combustible is in the
furnace. This type of firing is suited to either wet
or dry-bottom furnace operation or medium or
high volatile coals, and it is capable of extremely
high capacities.
Both weathering and
non-agglomerating ¶
Consolidated
Unconsolidated
*
This classification does not include a few coals that have unusual
physical and chemical properties and which come within the limits of
fixed carbon or BTU of the high-volatile bituminous and subbituminous ranks. All these coals either contain less than 48% dry,
mineral-matter-free fixed carbon or have more than 15 500 moist,
mineral-matter-free Btu.
t If agglomerating, classify in low-volatile group of the bituminous
class.
Moist Btu refers to coal containing its natural bed moisture but not
including visible water on the surface of the coal.
§ It is recognized that there may be non caking varieties in each
group of the bituminous class.
¶ There are three varieties of coal in the high-volatile C bituminous
group, namely, (1) agglomerating and non-weathering, (2)
agglomerating and weathering, and (3) non-agglomerating and non
weathering.
2.5
Occasionally, the admission of secondary air
along the front walls is used with considerable
success, particularly in connection with very lowvolatile coals, which require long flame travel,
or in high, narrow furnaces.
Impact firing, a form of vertical firing, consists of
burners located in an arch low in the furnace or
in the side walls and directed toward the furnace
door, with high velocities of both primary and
secondary air. This type of firing is used
exclusively in wet-bottom or slagging type
furnaces.
296
Furnace Heat Release and Heat Available.
Furnaces for pulverized coal firing are designed
either to remove the ash as molten slag
intermittently or continuously (wet bottom), or as
dry ash (dry bottom). Wet-bottom construction
generally is chosen for low-grade coals that
have low fusion characteristics, whereas drybottom construction often is selected for highfusion coals. Experience has shown, however,
that it is possible to design reliable dry-bottom
units to burn any grade of coal available, at high
boiler availability. Pulverized-fuel firing is used
for steam capacities ranging from 23,730 to
454,550 kgs. per hr. capacities above 68,180
kgs. per hr. being almost exclusively fired with
pulverized coal. The furnace heat release varies
3 per hr.
from 558,662 to 1,117,224 kilo Joules/m
782,071 to 819,313 kJ for best performance of
wet-bottom furnaces or for dry-bottom units
CHAPTER 15- FUELS AND LUBRICANTS
Table 15.2.1.2 Symbols for Grading Coal According Ash-Softening Temperature
Asht
Symbols
%, t inclusive
A4
A6
A8
AlO
A12
A14
A16
A18
A20
A20 Plus
0.0— 4.0
4.1 —6.0
6.1—8.0
8.1—10.0
10.1 —12.0
12.1 14.0
14.1 16.0
16.1 18.0
18.1 20.0
20.1 and higher
—
Softening Temperature of Ash
*F, Inclusive
Symbol
F28
F26
F24
F22
F20
F20 minus
2800 and higher
2600—2790
2400—2590
2200—2390
2000—2190
Less than 2000
Sulfur
t
Symbol
%, inclusive
S0.7
S1.0
S1.3
S1.6
S2.0
S3.0
0.0— 0.7
0.8—1.0
1.1—1.3
1.4—1.6
1.7—2.0
2.1 3.0
S5.0
S5.0 plus
3.1 5.0
5.1 and higher
—
—
—
—
—
t Ash and sulfur shall be reported to the nearest 0.1% by dropping the second
decimal figure when it is 0.01 to 0.04, inclusive, and by increasing the percentage
by 0.1% when the second decimal figure is 0.03 to 0.09, inclusive. For example 4.85
to 4.94%, inclusive, shall be considered to be 4.9%.
J Ash-softening temperatures shall be reported to the nearest 10 F. For example,
2,635 to 2,644 F, inclusive, shall be considered to be 2,640 F.
§ For commercial grading of coals, with ash less than 2%, ranges in the percentage
ash smaller than 2-4 are commonly used.
Fixed Carbon in coal = 100 %moisture %volatile -%ash. In anthracites, heating
value ranges from 14,800 to 15,500 Btu/Ib. In bituminous coal 13,000 to 15,500
Btu/Ib. In liquates, it may be as low as8 300 Btu/lb. See also Table 15.2.1.2(a) for
Quality of coals in the Philippines.
-
Note: °C
=
(°F
-
-
32)
burning coal with an ash-fusion temperature
above 1,150°C. The available furnace heat is
defined as the heat in the coal as fired, plus the
heat in the preheated air, minus one-half the
radiation of unaccounted-for losses, minus the
heating value in the unburned carbon. This
value, divided by the projected area, in square
feet, of the furnace wall tubes plus the plane of
the first row of boiler tubes, gives a useful factor
for comparing furnaces. For round tubes, the
projected area is taken as the diameter
multiplied by the length; and with finned tubes
and studded tubes, the projected area, including
fins and studs, is used. Most central station
boilers in this country have values for the
available furnace heat between 567,505 and
1,135,010 Kilo Joules per sq. m. of heatabsorbing surface.
Note:
Section 3.0 Coke
3.1
Coke is the solid, infusible, cellular residue left
after fusible bituminous coals are heated, in the
absence of air, above temperatures at which
active thermal decomposition of the coal occurs.
Pitch coke and petroleum coke of somewhat
different characteristics are obtained by similar
heating of coal-tar pitch and petroleum residues.
High temperature coke is made from coal at
temperature ranging from 815°C to 1,093°C
(average practice, 926°C to 1,037°C.
Low temperature coke
is formed
at
temperatures below 704°C. The residue, if made
from a non-cooking coal, is known as char.
Section 4.0 Wood and Hogged Fuel
°C
=
(°F 32) + 1.8
kg
lbs+2.2
M
=
ft.+3.28
kilo Joules (kJ) = BTU x 1.055
-
4.1
297
Wood fuel may come to the boiler plant in the
form of cordwood, slabs, edging, bark, sawdust,
or shaving and frequently several forms are
CHAPTER 15- FUELS AND LUBRICANTS
Table 15.2.1.la
Quality of Major Coal Fields in the Philippines
(Air-Dried Basis)
Total
Calorific
Value (BTU/LB)
Volatile
Matter (%)
Total
Moist (%)
Fixed
Carbon (%)
Ash
%
6 800—7 400
9 300—9 700
10 300 -12 000
36—38
41 —55
22—25
14— 16
8— 12
3—7
25—29
28—32
50—55
15— 18
8 16
9— 15
1.2— 1.6
8 200 —8 900
10500—11 300
9100—11 000
36 37
35—37
30—35
16 19
6—10
11 —14
34 36
42—47
1—6
5 —6
2—7
1—6
1.7—2
1.5—3
0.3—1.3
Sub-bituminous
Sub-bituminous
Sub-bituminous
Bituminous
12 900
11 000 113 000
8000—10 000
48
50 53
37-38
5
6
17-18
42
36-39
37-41
4
2-3
2-9
0.4
3-4.1
0.5-0.7
Bituminous
Sub-bituminous
Lignite-sub
Bituminous
12 000— 12 400
9 700— 10 400
10 500— 11 500
9 300— 12 2000
40
38-40
40-41
36-39
5-6
1 1-12
6-9
3-4
46-48
39-42
38-44
41-46
3-6
5-6
5-8
10-13
0.4-0.6
0.3-0.5
0.3-1
3-5
Bituminous
Sub-bituminous
Sub-bituminous
Sub-bituminous
Bituminous
8400—9 100
32-34
17-19
35-37
12-13
1.5-4.4
Sub-bituminous
NEGROS (East)
SURIGAO
Guigagult
Bislig
ZAMBOANGA
8600—9 300
8 800—9 700
12 700—13 100
37-40
31-34
24-28
8-9
1 2-14
2-4
28-34
34-38
56-57
17-20
1 1-13
5-7
2.4-3.8
0.5-1
0.4-0.9
Sub-bituminous
Sub-bituminous
Bituminous
Semi-anthracite
DAVAO
8 200— 11 000
33-44
18
36
9
0.6-1.7
Lignite-Sub
Bituminous
.
Coral Fields
CAGAYAN BASIN
Cauayan,lsabela
MaddelaQuirino Prov.
CATANDUANES
BATAAN
East
West
POLILIO ISLAND
QUEZON(Gen. Nakar)
SOUTHERN MINDORO
SEMIRARA ISLAND
—
CEBU
Angao-Dalaguete
Uling-Alpaco
Danao-Compostela
Toledo-Balamban
NOTE:
lb + 2.2
Kilo Joules (KJ)
—
—
—
s (%)
0.7— 11
---
—
—
Coral Fields
Lignite
Lignite-sub
Bituminous
kg
=
BTU x 1.055
I
o
Cl)
4
fi
Vertical firing
Impact firing
Horizontal firing
298
—
Corner or tangenflal
firing
CHAPTER 15— FUELS AND LUBRICANTS
available together. From 30 to 50% of the
lumber delivered to woodworking mills becomes
waste available as fuel, the percentage
depending on whether the mill is of the “rough”
or “finishing” type. Waste from finishing mills
usually runs 25 to 40% of lumber processed and
is usually of smaller size consist, is drier, and
contains less bark and foreign material.
Technically, “hog” fuel, a term sometimes
loosely applied to sawdust, shavings, and bark,
is only that wood which has been chopped up in
“hog” choppers, which may be (1) steel disks
with attached knives, (2) two concentric cones
bearing knives and revolving in a conical
housing, (3) a cylinder with attached knives
revolving a cylindrical housing, (4) “hammer
hogs”, in which wood is broken by impact of
hammer against anvils. Dull-knifed hogs may
shred rather than cut wood: such shredded
wood in long, stringy pieces may clog
mechanical feeders.
a.
b.
Properties of Woods. The major variable in
wood is moisture content; air-dried wood
seldom contains less than 12% water,
whereas kill-dried usually contains from 1 to
7%. Moisture in wood from rough mills
averages 30 to 50%; waste from logs floated
to mills often contains up to 70%. Well-dried
wood is hydroscopic; i.e., it will absorb
moisture from the air. The specific gravity of
wood ranges from 0.3 to 1.2; the heating
value of dry wood (except where resin
increases heating value) is approximately
proportional to the specific gravity. Moisture
in newly-felled wood varies with the species
but averages 40%.
Combustion of Wood and Wood Waste.
Require intelligent handling, knowledge of
their composition and the important
influence of moisture, and understanding of
the three-stage wood combustion process.
These three stages of conibustion involve
(1) evaporation of moisture, 2) distillation
and burning of volatile matter, and (3)
burning of fixed carbon, i.e., the residual
charcoal. However, these steps usually
overlap somewhat. The first and second
stages absorb heat from the furnace,
whereas the burning of volatile matter and
fixed carbon give up heat to the furnace.
There are three general methods of
wood fuels, through combinations
used. Wood fuels may be burned
moving bed on an inclined grate,
burning
maybe
(1) in
(2) in
299
suspension, as in spreader strokes, or (3) in
piles in flat grates. Method 3 is the slowest.
Method 1 tends to segregate the three
combustion stages (a not desirable effect). It
is necessary to supply excess air in burning
wood fuels.
Table 15.4.1.2 Fuel-gas Analysis for Complete
Combustion of Wood
Composition of Dry Products, % by Volume
%Excess Air
0
2
CO
20.1
02
0.0
2
N
79.9
20
16.8
3.6
79.6
40
14.4
6.1
79.5
60
12.5
8.0
79.5
80
11.2
9.5
79.3
100
10.0
10.6
79.4
Section 5.0 Miscellaneous Solid Fuels
5.1
Charcoal. Charcoal provided the only carbon for
steel making and other metal smelting from pre
historic times up to the eighteenth century in
Europe and up to early in the nineteenth century
in the United States, when coke gradually began
to take place of charcoal in steel making.
a.
Production. Charcoal is produced by partial
combustion of wood at about 400 C and with
limited air. It may be made in kilns, ovens,
buried pits, or any suitable type of enclosure
in which wood can be piled and burning can
be restricted through control of inlet air. The
object is to char the wood without burning
anymore of it than is necessary to
accomplish the charring operation. Kilns are
frequently constructed of mound like piles of
wood covered with sod of turf and provided
with a central fuel and with air-inlet ports
around the periphery. Kilns vary in capacity
from 4 to 12 cu. m. of wood. The time
required to char a kiln of wood depends on
the moisture content of the wood and the
size of the kiln. It may take as long as two
weeks. The process is complete when
smoke from the kiln becomes thin and blue.
Portable kilns that can be moved to new
supplies of wood have received increasing
attention.
b.
By Products. Both hardwoods and
softwoods are now used in the production of
charcoal; hardwood charcoal weights about
31 kgs. per cu. m. and softwood charcoal
about 28 kgs per cu. m. When very resinous
wood are processed in sloped clay-floor
kilns, tar is formed from the resin in the
wood. The tar collects on the flood and can
be drained off and recovered from small
CHAPTER 15— FUELS AND LUBRICANTS
charcoal operations. With operations of
sufficient size to make recovery and refining
economical, large volumes of gas, a watery
pyroligneous acid condensate, and tar can
be recovered. An average gas yield of
approximately 62.5 cu. m per cu. m. of wood
has been obtained from large commercial
,
2
plants. Typical gas composition is: CC
3.0%;
H,
3.5%;
,
4
CH
59%; CC, 33%;
Vapors, 1.5%. Considerable variation in gas
yield and composition is reported; for
example volumes of 36 to 62.5 cu. m. of gas
per cu. m. and methane content of 3.5 to
18%. The water pyroligneous acid contains
a complex mixture of organic acids,
alcohols, aldehydes, ketones, etc., and
approximately 80 to 90% water. Formic and
acetic acids, methyl (wood) alcohol,
formaldehyde, acetaldehyde, turpentine,
and acetone are some of the more familiar
by-products recovered. The tar is a complex
mixture containing most of the products
found in the pyroligneous acid and many
others. It may be distilled to give “light” oils,
“heavy” oils, and pitch.
c.
5.2
power in an engine, exclusive of oils with a
flash point below 37.7°C by the Tag closed
tester, and oils burned in cotton or wool-wick
burners. Fuel oils in common use fall into
four classes: (1) residual oils, which are
topped crude petroleum’s or viscous
residuum obtained in refinery operations; (2)
distillate fuel oils which are distillates
derived directly or indirectly from crude
petroleum; (3) crude petroleum’s and
weathered crude petroleum’s of relatively
tow commercial value; (4) blended fuels,
which are mixture of two or more of the
preceding classes.
6.2
Commercial Fuel Oil Specifications (ASTM
D396-48T) cover five standard grades limited by
the detailed requirements summarized in Table
15.6.2. The several grades are defined as: No. 1
a distillate oil intended for vaporizing pot-type
burners and other burners requiring this grade of
a distillate oil for general-purpose
fuel; No. 2
domestic heating in burners not requiring No. 1
fuel oil; No.4 an oil for burner installations not
a
equipped with pre-heating facilities; No. 5
equipped
installations
residual type oil for burner
an oil for
with pre-heating facilities; No. 6
a
permitting
pre-heaters
with
equipped
burners
high viscosity fuel.
—
—
—
—
Specifications. Charcoal is seldom sold on
specification; the usual market guarantees
relate only to weight per cu. m. and to
volatile and moisture content. The maximum
of 14% volatile and 2% moisture is
customarily established. The heating value
of charcoal ranges from 25,531 to 32,495
kJ/kg and can be approximately calculated
from Dulong’s formula.
—
Straw, Paper, and Miscellaneous Waste
Fuels. With properly designed equipment,
almost any solid material having a heating
value exceeding that required to evaporate the
moisture in the material can be used to produce
heat and power. The important consideration is
that an adequate and assured supply of the
material be available at a price, including
transportation and handling, to make the
installation economically sound. Table 15.5.2
gives the heat of combustion of various
substances.
a.
Flash Point (ASTM D93-46) is the
temperature to which oil must be heated to
give off sufficient vapor to form an
inflammable mixture with air. It varies with
apparatus and procedure, and both must be
specified when flash point is stated. The
minimum flash point usually is controlled by
law. If no legal requirements exist, minimum
values of Table 15.6.2 are used.
b.
Pour Point (ASTM D97-47) is the lowest
temperature at which oil will flow under
prescribed conditions.
c.
Section 6.0 Liquid Fuels
6.1
Characteristic of Fuel Oil
a.
Water and Sediment (ASTM D96-47) are
excluded almost entirely in No. 1 and 2 oils
but are allowed to limited extent in No. 4, 5,
and 6 oils. Water and sediment are
determined together by the centrifuge,
except that, in No. 6 oil water is determined
by distillation (ASTM D95-46) and sediment
is determined by extraction with benzol
(ASTM D473-46T).
Fuel Oil is defined (ASTM D288-47) as any
liquid or liquefiable petroleum products
burned for the generation of heat in a
furnace of firebox, of the generation of
d.
300
Carbon Residue (ASTM 0524-42). The
carbon residue test, in connection with other
tests and the use for which the oil is
CHAPTER 15— FUELS AND LUBRICANTS
intended, furnishes information and throws
light on the relative carbon-forming qualities
of an oil. For No. 1 and 2 oils, the Rams
bottom carbon residue test is made on 10%
bottoms. For medium viscosity and blended
oils, it is used to detect heavy residual
products.
e.
f.
g.
Ash (ASTM 0482-46). The ash test
determines the amount of non-combustible
impurities, which come principally from the
natural salts present in the crude oil, from
chemicals used in refinery operations, or
from sea water contamination, as in the
case residual fuels transported by sea. They
also may come from scale and dirt picked
up from containers and pipes. Depending on
its chemical composition, the ash in fuel oil
may cause rapid deterioration of refractory
materials in the combustion chamber,
particularly at high temperatures. Some ashproducing impurities are abrasive and
destructive to pumps, valves control
equipment, and other burner parts. Ash
specifications are included to minimize
these operating difficulties.
Distillation Temperatures (ASTM D86-46
for No. 1 oil, ASTM D158-41 for No. 2 oil) of
a sample under prescribed conditions are an
index of volatility. The 10% and 90% points
represent, respectively, temperatures at
which 10% and 90% of the sample are
distilled over. The end point is the maximum
temperature recorded by the distillation. The
10% point is an index of ease of ignition.
The 90% point and the end point are
specified to insure that the oil will burn
completely and produce a minimum of
carbon.
Table 15.5.2
Heat of Combustion of Various Substances,
on Dry Basis
Substance
Petroleum coke
#1 Gilsonite selects*
Asphalt
Pitch
Soot (from oil)
Soot (from smokeless coal)
Soot (Island Creek)
Soot (Red Jacket Thacker)
Soot (Crystal Block Winifrade)
Wood sawdust (oak)
Wood sawdust (pine)
Wood sawdust (pine)
Wood sawdust (hemlock)
Wood sawdust (fir)
Wood sawdust (spruce)
Wood shavings
Wood shavings (hardwood)
auto bodies
Wood bark (spruce)
Wood bark (hemlock)
Wood bark (fir)
Wood bark (fan)
Brown skins from peanuts
Corn on the cob
Rags (silk)
Rags (wool)
Rags (linen)
Rags (cotton)
Cotton batting
Corrugated fiber carton
Newspaper
Wrapping paper
Oats
Wheat
Oil (cottonseed)
Oil (lard)
Oil (olive)
Oil (paraffin)
Oil (rape)
Oil (sperm)
Candy
Butter
Casein
Egg white
Egg yolk
Fats (animal)
Hemoglobin (blood)
Waste hemp hurds
Cottonseed hulls (fusion 2342 F)
Cottonseed hull brans
(fusion 23071 F)
Pecan shells
Viscosity. is a measure of the resistance of
oil to flow (ASTM D88-44 for Saybolt
viscosity). It is the time in seconds in which
a definite volume of oil will pass through a
tube of specified dimensions at a definite
temperature. For oils having viscosities less
than 32 sec. Saybolt Universal, such as No.
1 fuel oil, it is necessary to determine
Kinematic viscosity in centistokes (ASTM
D445-46T).
Viscosity
decreases
as
temperature increases. Pre-heating makes
possible the use of oils of relatively high
viscosities
at
normal
temperatures.
Maximum viscosity is limited because of its
effect on oil flow in pipe lines and on the
degree of atomization that can be had in
15,800
17,699
17,158
15,120
11,787
7,049
5,425
10,569
4,951
8,493
9,347
9,676
7,797
8,249
8,449
8,248
8,878
8,817
8,753
9,496
7,999
10,431
8,100
8,391
8,876
7,132
7,165
7,114
5970
7,883
7,106
7,998
7,532
17,100
16,740
16,803
17,640
17,080
18,000
8,096
16,560
10,548
10,260
14,580
17,100
10,620
7,982
8,600
Coffee ground
8,675
8,893
10,058
Pecan shell (few meats left
in them)
10,144
*Material used for cores in foundries.
Note: kilo Joules = BTU x 1.055
Kg = lbs ÷ 2.2
301
Heating
Value, Btu
per Ib, dry
CHAPTER 15— FUELS AND LUBRICANTS
given burner equipment. The Say bolt
Universal viscosimeter is used for low
viscosity fuel oils, and the Say bolt Furol
viscosimeter for heavier oils. Other types
of viscosimeters for fuel oils are the
Redwood and Engler.
6.3
6.4
6.5
Section 7.0 Storage and Handling of Fuel
Oil
7.1
Firebrick and Refractory Cement. Firebrick
and refractory cements should be selected on
the basis of the service in which they are used.
A grade higher than absolutely necessary
should be chosen because of abuse under
extreme operating conditions. The life is
refractory material in combustion chambers is
shortened by sustained high temperature, by
rapid changes in temperature, and by panting or
vibration from combustion. High temperatures
result from operation above normal rating,
normal operation with insufficient combustion
chambers designed for high heat releases.
Rapid temperature changes may be reduced to
the minimum by the operating personnel. A cold
boiler should be brought up to operating
temperature and pressure as slowly as possible.
When taking the boiler out of service, registers
and dampers must be closed tightly to allow the
boiler to cool slowly. Panting is usually due to
improper drafts, faulty atomization, fluctuating oil
pressure or high heat releases. Sputtering
results from water in the oil or wet steam
supplied to steam-atomizing burners.
generally are
Fuel Oil Storage Tanks
classified by material, as steel or concrete; by
size, as gallons, etc; by location, as exposed or
inside, underground or buried; and by use, as
light or heavy oil tanks. The essential
requirements for tanks are tightness and
durability. The following specifications are
generally accepted standards. Local regulations
should be studied before installation. Tanks for
heavy oil usually have a manhole and provision
for a tank pre-heater, using either steam or hot
water. Such tanks should be designed to heat
the oil in the vicinity of the suction pipe to not
over 37.7°C.
—
a.
Capacity and Location of Tanks. The
location of a tank with respect to distance
from tank shell to line of adjoining property
or nearest building depends on the
construction, contents, equipment, and
greatest dimension (diameter, length, or
height) of the tank and should be in
accordance with Table 15.7.1.1
The minimum distance between shells of
any two all-steel, gas tight tanks should be
not less than one-half the greatest
dimension (diameter, length, or height) of
the smaller tank except that such distance
should not be less than 9910 mm; for tanks
of 68 130 litres or less, the distance need
not exceed 915 mm.
Furnace Floors. The burners’ manufacturer
usually specifies the furnace floor construction.
The several layers are as follows: (1) insulating
brick or material; (2) first course of brick, dry,
laid 1.6 mm apart to provide for expansion joints
broken between adjacent rows; (3) dry refractory
cement, filling all cracks and covering bricks to
depth of 3.17 mm; (4) second course of brick
similar to first, overlapping joints in first course;
and (5) day refractory cement as in (3). After
firing, the bricks take a permanent set and the
cement vitrifies to a hard surface. For airports
built into the floor, the bricks may be set in
refractory cement mortar.
Tanks should be so located as to avoid
possible danger from high water.
When tanks are located on a stream without
tide, they should, where possible, be down
stream for burnable property.
b.
Metal Combustion Chambers. For wet-base
domestic heating boilers and forced warm air
furnaces, stainless steel combustion chambers
are used extensively. Type 430 stainless steel
(17% chromium) is representative of the lowestgrade material that may be used for this service.
302
Fill Lines. Not less than 50 mm pipe should
be used for light oils (No. 1); for heavy oils
(No. 6), 150 mm or 200 mm pipe should be
used. A pipe too large is better than one too
small. The fill line for any storage tank
should pitch from the fill box to the tank. A
trap should be provided, either directly
inside or outside of the tank, or the fill line
sealed by ending it in the tank below the
bottom of the suction line. The fill line
always should be connected at the low end
of the tank and never cross-connected to
the vent pipe.
CHAPTER 15— FUELS AND LUBRICANTS
Table 15.7.la
Specifications for Underground Oil Storage Tanks
Maximum
Capacity,
Gal
Gage of
Metal
Weight of
Metal, lb
Per square
ft.
Table 15.7.1.1
Capacity and Location of All-Steel Tanks
-
285
560
1100
4000
12000
20000
30000
16
14
12
7
1/4
5/16
3/8
2.5
3.12
5
4.37
5
7.5
10.00
12.50
15.00
.
.
.
*Top of underground tanks to be not less than 305 mm
underground. Material to be galvanized steel, basic openhearth, or wrought-iron. Joints to be welded, or riveted and
caulked. When the tank is installed inside buildings without
enclosure, the maximum capacity is 1 040 litres and the
minimum thickness of 1.984 mm.
Note:
Class of
Tanks and
Contents
Approved
Attached
Extinguishing
System
or Approved
Floating_Roof
Yes
Group A for
refined
petroleum
products not
subject to
boil- over
litres = gals. X 3.785
mm = inch x 25.4
2 = Pounds/sq. Foot x 4.88
kg/rn
.
Distance
between and
Property Lines or
Nearest
Building
Not less than
greatest
dimension
(diameter,
length, or
height);
maximum
distance
required, 37
metre
Not less than 1
1/2 times the
greatest
dimension
(diameter,
length, or
height);
..
Group B for
refined
petroleum
products not
subject to
boil- over
Table 15.7.lb
Specifications for Above ground Oil Storage Tank
Maximum
Cageof
Metal
60
18
350
16
560
14
1100
12
Over
1100
Thickness of metal for outside aboveground tanks of over
1100 gal capacity to be calculated by the following formula:
H x D/8 450 x E, where t = thickness of metal in inches; H
= height of tank in feet above bottom of ring
under
consideration; D = diameter of tank in feet; E = efficiency of
vertical joint in ring under consideration where tensile
strength of steel be considered to be 55 000 psi and
shearing strength of rivets to be 40 000 psi. Minimum
thickness of shell or bottom is 3/16 in. and of roof 1/8 in.
Yes
*
Note:
litre = gallon z 3.785
mm = inch x 25.4
kPa = psi x 6.895
m =ft÷3.28
Kpa = psi x 6.895
c.
Vent Pipe. All fuel oil storage tanks must be
vented. The size of the vent pipe should be
proportion to the size of the fill line and
should never be less than 32 mm pipe.
Where tight fill box connections are used for
pressure filling, the vent must be of
adequate size to prevent pressures being
built up in the storage tank.
Section 8.0 Gasoline and Kerosene
8.1
Gasoline is defined (ASTM D288-47) as a
refined petroleum naphtha which by its
composition is suitable for use as a carburetant
in internal combustion engines. The term is
often applied to hydrocarbon liquids used as
solvents for specific purposes, such as cleaning,
manufacture of rubber cement, of manufacture
303
maximum
Group C for
crude
petroleum
and
flammable
liquid subject
to boil-over
Yes
Group D for
crude
petroleum
and
flammable
liquid subject
to boil-over
No
distance
required, 53.0
metre
Not less than
twice the
greatest
dimension
(diameter,
length, or
height);
minimum
distance
required, 6.0
metre, maximum
distance
required, 53.4
metre
Not less than
three times
greatest
dimension
(diameter,
length, or
height);
minimum
distance
required, 6.0
metre; maximum
distance
required, 107.0
meter
CHAPTER 15— FUELS AND LUBRICANTS
usually free
compounds,
impurities.
of paints or varnishes. For example, cleaners
naphtha or Standard solvent (ASTM D484-40)
has a distillation range of about 148.8°C to
204.4°C and a minimum flash point requirement
of 37.7°C.
water, acid
deleterious
The elementary composition of gasoline by
weight is, in general, not far from 85%
carbon and 15% hydrogen. The air-fuel ratio
for stoichiometric requirements in the
combustion of gasoline and kerosene varies
between 14 and 15 kg of air per kg of fuel.
Although gasoline and kerosene are not
invariable in composition and properties, they
vary only within limits of quality requirements
recognized by refiners and consumers of those
products.
a.
of suspended
other
and
Gasoline ordinarily is graded by volatility
and antiknock value, or octane number, into
motor gasoline of regular and premium
grades and into aviation gasoline of several
antiknock grades, of which the most
generally used are 91/98 and 100/130
(ASTM D910-47). Typical characteristics of
gasoline are listed in Table 15.8.1.1. Other
typical physical properties of gasoline are:
(1) volume coefficient of thermal expansion,
per °C at 15.5°C 0.0006 to 0.0007 (ASTM
D206-36); (2) latent heat of vaporization, at
1 atm. vapor pressure, 130 Btu per Ib; (3)
specific heat of vapor at 1 atm. pressure and
37.7°C 0.4 Btu per (lb x °F); (4) electric
restivity of water free liquid, 2 X 10 ohm per
cu. cm; (5) dielectric constant at 20°C 2.2
referred to air as unity; (6) surface tension
against air at 20°C 21 dynes per cm for
aviation grade, 25 dynes per cm for motor
gasoline.
Motor gasoline for automotive use, is
mixture of hydrocarbons distilling in the
range of 37.7°C to 204.4°C by the standard
method of test (ASTM D86-46). The
hydrocarbons belong chemically to four
olefins,
paraffin,
classes;
principal
naphtenes, and aromatics. A typical motor
gasoline is a blend of (1) straight-run or
prime-cut naphtha, i.e., the portion of natural
crude oil boiling at temperatures up to
204.4°C; (2) reformed naphtha, i.e., the
product of the same volatility obtained by
catalytic
or
by
treatment
thermal
dehydrogenation of the heavy straight-run
naphtha; (3) cracked naphtha, i.e., the
product of the same volatility obtained by
thermally or catalytically decomposing gas
oil and less volatile portions of the crude oil;
and (4) casing head gasoline and other light
ends, i.e., the liquefiable hydrocarbons,
including substantially none more volatile
than isobutance, normally carried as vapor
in natural gas or in stabilizer gases from
cracking processes.
Compounds other than hydrocarbons occur
in only very minor proportions in gasoline.
Tetraethyl lead is often present, usually as
an anti-knock compound in concentration
not exceeding 3 cc per gal or motor
gasoline. Sulfur compounds of non corrosive
properties may be present, since sulfur
compounds occur in crude oil, but their
concentration in gasoline rarely represents a
content of sulfur greater than 0.1% by
weight. When stored for a long time,
gasoline may form organic peroxides up to
about 200 parts of active oxygen per million
parts of gasoline, and resinous polymers,
called gum, up to about 30 mg. per 100 cc
of gasoline. Many commercial gasoline
of
concentrations
minor
contain
antioxidants, and some contain solvent oil to
guard against the deposition of gum.
Commercial gasoline on the market are
8.2
Explosive Mixture of Gasoline. Mixtures of air
and gasoline vapor containing from 1.3 to 6.0%
of gasoline vapor by volume are explosive.
8.3
Kerosene is defined as a petroleum distillate
having a flash point not below 22.8°C as
determined by the Abel tester (which is
as
22.8°C
to
equivalent
approximately
determined by the Tag closed tester, ASTM
standard method D56) and suitable as an
illuminant when burned in a wick lamp.
-
Typical kerosene have the following ranges of
properties: distillation, 160 to 287.8°C. API
gravity, 40 to 48 degrees; Tag flash 43.3 to
54.4°C, Kinematic viscosity at 37.7°C 1.4 to 2.0.
Other properties are listed in Table 15.8.4
Even in areas where electrification has made
kerosene lamps obsolete, kerosene has
continued to be an important fuel for heating
purposes, being consumed in wick type and
various vaporizing-type burners in stoves,
304
CHAPTER 15— FUELS AND LUBRICANTS
Table 15.8.1.1
Characteristics of Typical Gasolines
Distillation (ASTM,
D86-46)
Use Summer Automotive Aviation
Grade Regular Premium 100/130
Initial boiling point, °F
101
102
104
10% evaporated at °F
140
140
140
50% evaporated at °F
230
225
203
90% evaporated at °F
338
320
262
Final boiling point, °F
400
356
320
7.8
7.8
6.8
Vapor pressure, psi at
1 OOF
Motor octane number
(ASTM D357-47)
which 2,437 kJ per kg. at 25°C. It is sometimes
used in about 20% concentration as a
supplement in gasoline, particularly in countries
lacking petroleum resources. Such blended
gasoline generally contain about 15% benzol
also; in order to make the blend less likely to be
separated into two phases in the presence of
water. Aqueous alcohols may be injected as
auxiliary fuel in the intake manifold of Otto cycle
engines being operated at full power output. The
relatively high latent heat of vaporization of the
alcohols, which serves to cool the fuel-air
mixture, and their relatively high antiknock
value, especially in rich fuel-air mixtures, permit
higher power output than the knocking tendency
of the main fuel, if used alone, would permit.
74
78
Note
100
8.5
=
BTU x 1.055
lbs ÷ 2.2
°C= °F 32
1.8
—
heaters, and furnaces. In such cases, the
product is frequently known as range oil. The
specifications for No. 1 fuel also include
products of the kerosene type.
8.4
kJ
kg
Article 15.9 Other Liquid Fuels
Table 15.8.4 Specific Volume and Other Properties
of Gasoline and Kerosene
I
Specific Volume of gasoline and kerosene
completely vaporized at 1 atm. pressure and at
15.6°C are listed in Table 15.8.4 together with
some typical values of other properties which
normally vary with the densities of these
products.
Gasoline
Kerosene
For the liquid
Gravity,
Alcohol.
The
alcohol
most
frequently
considered as fuel for internal combustion
engines is ethyl alcohol, sometimes called grain
alcohol. Its modern chemical name is ethanol.
Two other alcohols that have been used as fuel
are methanol and isopropanol, which are also
called methyl alcohol and isoprophyl alcohol,
respectively.
*
55
API
70
40
45
50
0.7587 0.7389 0.7201 0.7022 0.8251 0.8017 0.7796
Pounds per
gallon
6.316
6.151
5.994
5.845
6.870
6.675
6.490
0.500
0.515
0.530
0.545
0.475
0.495
0.505
0.5
1.4
1.6
2.0
Viscosity,
centipoises* at
68 F
Not heating
value, at
constant
pressure,
Btu per lb
.......
0.5
.......
18,500 18,700 18,900 19,100 18,700 18,900 19,100
For the Vapor
Specific vol., Cu ft
per lb.
at6OF
The gross (higher) heating value of pure ethanol
is 29,639 kJ per kg and its net (lower) heating
value at constant pressure is 26,889 kJ per kg.
The products of its complete combustion in
oxygen are carbon dioxide and water. For
aqueous alcohol the net calorific value is lower,
owing in part to the inertness of water and to the
absorption of its latent heat of vaporization,
65
Specific gravity,
60°/60 F
Specific heat at
100F, Btu per (lb
x°F)
Ethanol has the chemical formula, C
OH.
5
H
2
When sold for industrial use; it is mixed with a
minor proportion of a denaturant to make it unfit
for human consumption, since alcohol for
beverage has subject to special taxation.
60
3.45
3.60
3.05
*Centipoise is the ems unit of viscosity and is equal to
kinematic viscosity in centistokes X the density of the
liquid.
Note:
305
°C=°F—32
1.8
CHAPTER 15— FUELS AND LUBRICANTS
liters = gals x 3.785
kg lbs. ÷ 2.2
8.6
8.7
Coal Tar and Tar Oil Coal tar is a product of
the destructive distillation of bituminous coal
carried out at high temperature. A typical
composition of tar is: C, 86.7%; H, 6.0%; N,
0.1%; S, 0.8% 0, 3.1%; ash, 0.1%; water, 3.2%.
The black color is due to free carbon in
suspension (about 4%). The high heating value
equals 37,925 kJ per kg. The viscosity is about
140 Say bolt sec at 60°C. Coal tar weighs 1.14
kg per liter. This analysis shows tar to have
almost the same chemical composition as the
combustible matter of the coal from which it is
made. Tar is used principally in reheating
furnaces and open-hearth furnaces of steel
works. It is not easily obtainable in the open
market. Since it is by-product, its price is more
or less arbitrary.
Table 15.9.3
ercial Propane and Butane
Comm
of
ties
Proper
Propane Butane
Property
—
Liquefied Petroleum Gases (LPG) are
mixtures of hydrocarbons liquefied under
pressure for efficient transportation, storage,
and use. They are generally composed of
butane,
propylene,
propane,
ethylene,
isobutene, and butylenes. Commercially, they
are classed as propane, propane-butane
mixtures, and butane. They are odorless,
colorless, and non-toxic. They should always be
odorized so that leaks may be detected long
before the lower explosion limit of the gas-air
mixture is reached. These gases are heavier
than air and seek ground level. If leaks will result
if dangerous accumulations collect and are not
dispersed by wind or other means, an automatic
be installed to
shut-off safety device shall
the regulator in
after
lines
protect the LPG pipe
the flexible
before
and
lines
piping
rigid
connection to each burner. Liquefied petroleum
gases are derived in most part from gases
produced in petroleum refining operations and
also in substantial quantities from natural gas.
The sulfur content is generally low particularly in
gases produced from natural gas. Butane is not
used as extensively as propane for two reasons:
(1) its relatively high boiling point makes it
necessary to add external heat when the
temperature drops below 0°C; and (2) butane
has high economic value in the manufacture of
synthetic rubber and for high octane gasoline.
The physical properties of propane and butane
are given in Table 15.9.3.
Chemical composition
Boiling point, °F
Specific gravity, liquid, at 60/60 F
Specific gravity, vapor, at 60 F, 14
psia (air = 1)
Specific heat, vapor, at 14 psia,
Btu/Ib, cy
Specific heat, vapor, at 14 psia,
Btu.lb, cx
Heat of vaporization, at 14 psia,
Btu/lb
Weight, lb/gal
Vapor produced, cu ft/gal
Heat content, gross Btu/lb
Explosion limits, % in air (lower)
Explosion limits, % in air (upper)
Air required for combustion, lb/lb
of fuel
C
8
H
3
-43.8
0.508
0
C
1
H
4
+31.1
0.584
1.522
2.006
0.390
0.396
0.346
0.363
183
4.23
36.5
21,690
2.0—2.4
7.0-9.5
15.6
166
4.86
31.8
21,340
15.-1.9
5.7-8.5
15.4
VAPOR PRESSURE of LP-Gases
250
200
ro/
150
100
50
But ne
40
-20
0
20
40
60
—
80
100
120
The