STANDARD
DNV-ST-F101
Edition August 2021
Amended December 2021
Submarine pipeline systems
(Preview copy)
The PDF electronic version of this document available at the DNV website dnv.com is the official version. If there
are any inconsistencies between the PDF version and any other available version, the PDF version shall prevail.
DNV AS
FOREWORD
DNV standards contain requirements, principles and acceptance criteria for objects, personnel,
organisations and/or operations.
©
DNV AS August 2021
Any comments may be sent by e-mail to rules@dnv.com
This service document has been prepared based on available knowledge, technology and/or information at the time of issuance of this
document. The use of this document by other parties than DNV is at the user's sole risk. DNV does not accept any liability or responsibility
for loss or damages resulting from any use of this document.
Changes - current
CHANGES – CURRENT
This document supersedes the October 2017 edition of DNVGL-ST-F101.
The numbering and/or title of items containing changes is highlighted in red.
Amendments December 2021
Topic
Reference
Description
Risk reduction by PSS
[3.4.2.7]
Removed unnecessary reference to figure in App.B.
Local buckling equation
limitation
[5.4.4.3]
Corrected limit for t1/tCRA to be > 3.
Locak buckling - combined
loading criteria
[5.4.6.6]
Corrected equations for backing steel and CRA characteristic
flow stress ratio.
Pipe wall thickness of bend
[5.6.2.2]
Updated guidance note to clarify definition of t1.
Fittings fire durability
[5.6.3.5]
Added subsection for requirements for fire durability.
Buckle detection
Table 10-1
Added precision for Table 10-1 to be applicable during
installation.
Changes August 2021
Topic
Reference
Description
Define
Whole document
'Define' has in many places previously been erroneously used
instead of 'specify'.
Definitions
[1.6.2]
Definitions appearing throughout the document have been
moved to definition of terms.
CO2 fluid category
[2.3.2]
This classification was previously recommended but has now
become compulsory.
Restrained force calculation for
lined and clad pipe
[4.7.4]
A more precise equation of multi layer pipe is provided.
Not fully rated pipelines
[5.4.2]
For accidental scenarios, e.g. failure of HIPPS, frequency
dependent safety factors shall be developed by user.
Lined and clad limit states
[5.3], [5.4]
Limit states for lined and clad pipes including the strength of
the corrosion resistant material are provided.
Local buckling
[5.4.6]
Validity range has been extended.
Super duplex material
[7.3]
Clarified that duplex steels with defined parameter PRE ≥ 40
shall be subjected to pitting corrosion test. Also allowed a
lower Molybden to meet available and acceptable super duplex
grades.
Qualification of welding
procedures
App.C
Removed requirement of max. difference between weld
coupons when all are fully tested. Modifications in essential
variables.
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Submarine pipeline systems
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Rebranding to DNV
Reference
All
Description
This document has been revised due to the rebranding of DNV
GL to DNV. The following have been updated: the company
name, material and certificate designations, and references to
other documents in the DNV portfolio. Some of the documents
referred to may not yet have been rebranded. If so, please see
the relevant DNV GL document.
Editorial corrections
In addition to the above stated changes, editorial corrections may have been made.
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Changes - current
Topic
The current update of the standard has been developed based on the results of a joint industry project (JIP).
The following companies, listed in alphabetical order, are acknowledged for their contributions to the JIP.
Lined and Clad JIP
Acergy
GDF Suez
Serimax
Total
Bergrohr
Gieminox / SPFA Australia
Shell
Tubos de Acero de Mexico
BP
Inpex
Equinor
Woodside
Butting
JSW
Subsea7
CladTek
Neptune Energy
TAMSA Tenaris
ExxonMobil
Petrobras
TechnipFMC
Local buckling - combined loading
Work on extension of combined loading formulation to thicker pipes organized by European Pipeline Research
Group (EPRG).
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Changes - current
Acknowledgements
Changes – current.................................................................................................. 3
Acknowledgements................................................................................. 5
Section 1 General.................................................................................................. 11
1.1 Introduction.................................................................................... 11
1.2 Objective.........................................................................................11
1.3 Scope.............................................................................................. 11
1.4 Application...................................................................................... 11
1.5 References...................................................................................... 13
1.6 Definitions and abbreviations......................................................... 21
Section 2 Safety philosophy.................................................................................. 43
2.1 General........................................................................................... 43
2.2 Safety philosophy structure............................................................ 43
2.3 Risk basis for design...................................................................... 47
Section 3 Concept and design premise development............................................ 50
3.1 General........................................................................................... 50
3.2 Concept development..................................................................... 51
3.3 Design premise............................................................................... 52
3.4 System design principles................................................................ 57
Section 4 Design - loads....................................................................................... 62
4.1 General........................................................................................... 62
4.2 Functional loads..............................................................................63
4.3 Environmental loads....................................................................... 65
4.4 Construction loads.......................................................................... 70
4.5 Interference loads.......................................................................... 71
4.6 Accidental loads.............................................................................. 71
4.7 Design load effects......................................................................... 72
Section 5 Design – limit state criteria...................................................................78
5.1 General........................................................................................... 78
5.2 System design requirements.......................................................... 79
5.3 Design format................................................................................. 84
5.4 Limit states..................................................................................... 90
5.5 Special considerations.................................................................. 111
5.6 Pipeline components..................................................................... 116
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Contents
CONTENTS
5.8 Installation and repair.................................................................. 123
Section 6 Design - materials engineering........................................................... 127
6.1 General......................................................................................... 127
6.2 Materials selection for line pipe and pipeline components............ 127
6.3 Materials specification.................................................................. 133
6.4 Corrosion control.......................................................................... 136
Section 7 Construction – line pipe...................................................................... 143
7.1 General......................................................................................... 143
7.2 Carbon manganese steel line pipe................................................ 147
7.3 Corrosion resistant alloy line pipe................................................ 162
7.4 Clad or lined steel line pipe.......................................................... 167
7.5 Hydrostatic testing....................................................................... 172
7.6 Non-destructive testing................................................................ 174
7.7 Dimensions, mass and tolerances................................................. 176
7.8 Marking, delivery condition and documentation............................184
7.9 Supplementary requirements........................................................ 185
Section 8 Construction - components and pipeline assemblies.......................... 195
8.1 General......................................................................................... 195
8.2 Component requirements..............................................................196
8.3 Materials....................................................................................... 207
8.4 Manufacture.................................................................................. 210
8.5 Mechanical and corrosion testing................................................. 213
8.6 Pipeline assemblies.......................................................................216
8.7 Hydrostatic testing....................................................................... 220
8.8 Documentation, records, certification and marking.......................222
Section 9 Construction - corrosion protection and weight coating...................... 224
9.1 General......................................................................................... 224
9.2 External corrosion protective coatings..........................................225
9.3 Concrete weight coating............................................................... 226
9.4 Manufacture of galvanic anodes................................................... 229
9.5 Installation of galvanic anodes..................................................... 229
Section 10 Construction – offshore..................................................................... 231
10.1 General....................................................................................... 231
10.2 Pipe assemblies onshore.............................................................232
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Contents
5.7 Supporting structure.....................................................................122
10.4 Installation spread......................................................................234
10.5 Welding and non-destructive testing.......................................... 243
10.6 Pipeline installation.................................................................... 244
10.7 As-laid survey............................................................................. 250
10.8 Post-lay intervention (seabed intervention and pipeline
protection).......................................................................................... 251
10.9 Tie-in...........................................................................................253
10.10 Pre-commissioning....................................................................255
10.11 As-built survey..........................................................................259
10.12 Documentation.......................................................................... 260
10.13 Installation manual................................................................... 260
Section 11 Operations and abandonment........................................................... 264
11.1 General....................................................................................... 264
11.2 Commissioning............................................................................ 266
11.3 Integrity management system.................................................... 266
11.4 Integrity management process................................................... 269
11.5 Re-qualification........................................................................... 275
11.6 De-commissioning....................................................................... 277
11.7 Abandonment.............................................................................. 278
Section 12 Documentation.................................................................................. 279
12.1 General....................................................................................... 279
12.2 Design......................................................................................... 279
12.3 Construction - manufacturing and fabrication.............................282
12.4 Construction - installation and pre-commissioning..................... 284
12.5 Operation - commissioning......................................................... 284
12.6 Operation.................................................................................... 285
12.7 Abandonment.............................................................................. 286
12.8 DFI resumé................................................................................. 286
12.9 Filing of documentation.............................................................. 288
Section 13 Commentary (informative)................................................................ 289
13.1 General....................................................................................... 289
13.2 Safety and design philosophy..................................................... 289
13.3 Loads.......................................................................................... 290
13.4 Design criteria............................................................................ 291
13.5 API material grades.................................................................... 297
13.6 Pipe-in-pipe.................................................................................297
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Contents
10.3 Pipeline route, pre-installation survey and preparation.............. 233
Section 14 Bibliography...................................................................................... 315
14.1 References.................................................................................. 315
Appendix A Fracture limit state of girth welds....................................................317
Appendix B Mechanical testing and corrosion testing......................................... 318
B.1 General......................................................................................... 318
B.2 Mechanical testing and chemical analysis.....................................318
B.3 Corrosion testing.......................................................................... 329
Appendix C Welding............................................................................................ 338
C.1 General......................................................................................... 338
C.2 Welding equipment, tools and personnel...................................... 339
C.3 Welding consumables................................................................... 342
C.4 Welding procedures...................................................................... 345
C.5 Qualification of welding procedures............................................. 353
C.6 Examination and testing for welding procedure qualification........ 362
C.7 Welding and post weld heath treatment requirements................. 368
C.8 Material and process specific requirements.................................. 375
C.9 hyperbaric welding....................................................................... 379
Appendix D Non-destructive testing....................................................................385
D.1 General......................................................................................... 385
D.2 Manual non-destructive testing and visual examination of
welds.................................................................................................. 387
D.3 Manual non-destructive testing and visual examination of plate,
pipe and weld overlay........................................................................ 411
D.4 Non-destructive testing and visual examination of forgings......... 416
D.5 Non-destructive testing and visual examination of castings......... 421
D.6 Automated non-destructive testing.............................................. 426
D.7 Non-destructive testing of pipe body of welded pipes.................. 427
D.8 Non-destructive testing of linepipe at pipe mills.......................... 433
Appendix E Automated ultrasonic girth weld testing.......................................... 461
E.1 General......................................................................................... 461
E.2 Basic requirements....................................................................... 461
E.3 Procedure......................................................................................471
E.4 Calibration (sensitivity setting).................................................... 472
E.5 Field inspection............................................................................. 475
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Contents
13.7 Installation................................................................................. 312
E.7 Evaluation and reporting.............................................................. 481
E.8 Qualification.................................................................................. 482
E.9 Project specific automated ultrasonic testing procedure
validation............................................................................................ 492
E.10 Validity of qualification............................................................... 494
E.11 Determination of wave velocities in pipe steels.......................... 495
Appendix F Requirements for shore crossing and onshore sections.................... 497
F.1 General..........................................................................................497
F.2 Safety philosophy..........................................................................502
F.3 Design premise............................................................................. 505
F.4 Design........................................................................................... 507
F.5 Construction.................................................................................. 509
F.6 Operation...................................................................................... 511
F.7 Documentation.............................................................................. 511
Changes – historic.............................................................................................. 512
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Contents
E.6 Re-examination of welds.............................................................. 481
SECTION 1 GENERAL
1.1 Introduction
Submarine pipeline systems constitute an essential part of an offshore hydrocarbon field development. They
are used for transporting unprocessed well fluid, export or processed fluid or injection fluids for different
purposes. Even though the pipeline structure may appear simple, the extent of the pipeline system entails
a significant field development cost. Most pipeline systems are therefore optimized and built to specific
geometry and material requirements with the objective of minimizing lifetime costs. The major benefits in
using this standard are:
— application of safety-class methodology, linking acceptance criteria to the consequence of failure by limitstate functions in a load and resistance factor design (LRFD) format that allows new innovative design
solutions to be developed
— providing industry accepted manufacturing and construction specifications for the complete pipeline
system
— close link between requirements for the design, manufacture, construction and operation.
This standard is in general in conformity with ISO 13623 and ISO 3183.
1.2 Objective
The objective of this standard is to provide an internationally acceptable framework for submarine
pipeline systems in all lifetime phases, with a focus on structural assessment, with the aim of obtaining an
appropriate and consistent level of safety.
1.3 Scope
This standard provides requirements and recommendations for the concept development, design,
construction, operation and abandonment of pipeline systems, with the emphasis on structural integrity. The
following topics are covered:
—
—
—
—
—
—
—
—
—
—
—
—
safety philosophy framework and target failure probabilities
design basis including surveys, environmental data and soil sampling
design criteria including the layout, LRFD criteria and functional criteria
material selection and corrosion control, i.e. pre-manufacturing considerations
line pipe specification for three types of pipes; CMn pipes, CRA pipes and lined/clad pipes
component manufacturing specifications, additional to industry standards, and pipeline assemblies
corrosion, insulation and weight coating specifications
offshore construction/installation and pre-commissioning requirements
operation and abandonment requirements
material testing specifications
welding specifications
non-destructive testing (NDT) specifications.
1.4 Application
The applicability of this standard is given in Table 1-1. The standard shall be applied in its entirety.
Technologies that are not covered by existing, validated requirements, and where failure poses a risk to
life, property or the environment, or presents a financial risk, shall be qualified. Recommended practices for
technology qualification are given in DNV-RP-A203.
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Table 1-1 Applicability of standard
General
Application
Pipeline systems in the petroleum and natural gas industries that can be
categorized into one of the safety classes defined in this standard.
Serves as a technical reference document in contractual matters between the
purchaser and contractor. Provides requirements for designers, purchasers, and
contractors.
Phases
Concept development, design, construction, operation and abandonment.
Pipeline types
Single rigid metallic pipeline systems, pipeline bundles of the piggyback type and
1)
pipeline bundles within an outer pipe .
Pipe-in-pipe.
Buckle arrestors, bends.
Risers and compliant risers are covered by DNV-ST-F201 Riser systems.
Pipeline components
Fittings, flanges, valves, mechanical connectors, CP insulating joints, anchor
flanges, pig traps, clamps, forgings and couplings.
Extent/battery limits
Pipeline system in such a way that the fluid transportation and pressure in the
2), 3)
submarine pipeline system are well defined and controlled
.
Geometry and configuration
Dimensions
Diameters above 60 mm.
Explicit criteria for local buckling and combined loading are given for straight pipes
with D/t2 < 45.
Configurations
Tees, wyes, PLEM or PLET, spools which are an integrated part of the pipeline.
Water depth
No limitation.
Loads
Pressure
No limitation.
Temperature
No limitation.
Global deformations
No limitation.
Material
Line pipe
C-Mn steel line pipe. Material grade limited to, including, X80 (DNV 555).
Duplex and super duplex steel and 13Cr martensitic steel.
Clad and lined line pipe.
Pipeline components
Bends, fittings, flanges, valves, mechanical connectors, SP insulating joints, anchor
flanges, buckle arrestors, pig traps clamps and couplings.
Fluids
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Fluids
— Non-flammable water-based fluids.
— Flammable and/or toxic fluids which are liquids at ambient temperature and
atmospheric pressure.
— Non-flammable fluids which are non-toxic gases at ambient temperature and
atmospheric pressure.
— Non-toxic, single-phase natural gas.
— Flammable and/or toxic fluids which are gases at ambient temperature and
atmospheric pressure condition and which are conveyed as gases and/or
liquids.
For CO2 pipelines, DNV-RP-F104 applies regarding material selection, corrosion and
sour service evaluations, and operation.
Sour service
Generally conforming to ISO 15156.
Installation
Method
S-lay, J-lay, towing and laying methods introducing plastic deformations.
Installation requirements for protective and anchoring structures are also included.
1)
Umbilicals intended for control of subsea installations are not included in this standard. Individual pipes, within an
umbilical, made of materials applicable to this standard, may be designed according to this standard.
2)
Different parts of the pipeline system may be designed to different standards or recommended practices. It
is important to identify differences between these at an early stage and assess these. Examples of conflicting
requirements are; pressure definitions and system test pressure requirements.
3)
The operator may apply this standard on sub-sets within the limits of this standard. Examples of excluded items are
smaller diameter piping such as kicker lines and designs of these in accordance with, e.g., ISO 15649.
1.5 References
1.5.1 General
In the context of this document, the term standard shall be understood to cover document types such as
codes, guidelines and recommended practices in addition to bona fide standards.
The standards in Table 1-2 and Table 1-3 include provisions which, through reference in the text, constitute
provisions of this standard.
The edition valid at the time of publishing this document applies, unless dated references are given. For DNV
documents, the latest edition applies.
References are defined as either normative or informative. Normative references in this document are
indispensable for its application. Informative references provide additional information intended to assist the
understanding or use of the document.
Guidance note:
Normative references are typically referred to as 'testing shall be performed in accordance with ISO xxx', while informative
references are typically referred to as 'testing may be performed in accordance with ISO xxx or ISO yyyy', or 'recommended
practice on xx is given in DNV-RP-Fxxx'.
---e-n-d---o-f---g-u-i-d-a-n-c-e---n-o-t-e---
In case of conflict between this standard and referenced DNV standards or recommended practices, the
standard or recommended practice with the latest edition date shall prevail.
Other recognized standards may be used provided it can be demonstrated that these meet or exceed the
requirements of the referenced standards.
This standard is intended to conform to ISO 13623: Petroleum and natural gas industries - Pipeline
transportation systems, specifying functional requirements for offshore pipelines and risers.
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Guidance note:
The following deviations from ISO 13623 standard are intentional:
—
For a design life of less than 33 years, a more severe environmental load is specified in this standard, in agreement with ISO
16708.
—
applying the supplementary requirements U, for increased utilization, this standard allows 4% higher pressure containment
utilization than ISO 13623.
—
the equivalent stress criterion in ISO 13623 may, under some conditions, allow higher utilization than this standard.
—
requirements for system pressure tests (pressure tests) are less stringent. This standard also allows system pressure tests to
be replaced by alternative means on certain conditions.
—
minor differences may appear depending on how the pipeline has been defined in safety classes. ISO 13623 does not use the
concept of safety classes.
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This standard is intended to conform to ISO 3183 Annex J for C-Mn steel line pipe limited to, including, X80
(DNV 555), but with modifications and amendments according to this standard.
Guidance note:
The latest revision of the DNV publications may be found in the publication list at the DNV website www.dnv.com.
Amendments and corrections to the DNV publications are published on www.dnv.com when relevant.
---e-n-d---o-f---g-u-i-d-a-n-c-e---n-o-t-e---
Additional requirements or modified requirements compared to the stated ISO standards are denoted by AR
or MR at the end of the paragraph. This applies to [7.2] and [9.3].
Modified requirements compared to the stated ISO standards are given in this standard by stating the ISO
paragraph number in brackets prior to the modified requirements. This applies to Sec.8.
Guidance notes provide additional information, clarification or examples to the paragraph to increase the
understanding of the requirement. Guidance notes do not contain requirements.
1.5.2 DNV references
Table 1-2 DNV references
Document code
Title
DNV-CG-0051
Non-destructive testing
DNV-OS-A101
Safety principles and arrangements
DNV-OS-C101
Design of offshore steel structures, general - LRFD method
DNV-OS-E201
Oil and gas processing systems
DNV-OS-E301
Position mooring
DNV-SE-0160
Technology qualification management and verification
DNV-SE-0475
Verification and certification of submarine pipelines
DNV-ST-C501
Composite components
DNV-ST-F201
Riser systems
DNV-ST-N001
Marine operations and marine warranty
DNV-RP-A203 Sec.1
Technology qualification
DNV-RP-B401
Cathodic protection design
DNV-RP-B204
Welding of subsea production system equipment
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Document code
Title
DNV-RP-C203
Fatigue design of offshore steel structures
DNV-RP-C205
Environmental conditions and environmental loads
DNV-RP-C212
Offshore soil mechanics and geotechnical engineering
DNV-RP-F101
Corroded pipelines
DNV-RP-F102
Pipeline field joint coating and field repair of line pipe coating
DNV-RP-F103
Cathodic protection of submarine pipelines
DNV-RP-F104
Design and operation of carbon dioxide pipelines
DNV-RP-F105
Free spanning pipelines
DNV-RP-F106
Factory applied pipeline coatings for corrosion control
DNV-RP-F107
Risk assessment of pipeline protection
DNV-RP-F108
Assessment of flaws in pipeline and riser girth welds
DNV-RP-F109
On-bottom stability design of submarine pipelines
DNV-RP-F110
Global buckling of submarine pipelines
DNV-RP-F111
Interference between trawl gear and pipelines
DNV-RP-F112
Duplex stainless steel - design against hydrogen induced stress cracking
DNV-RP-F113
Pipeline subsea repair
DNV-RP-F114
Pipe-soil interaction for submarine pipelines
DNV-RP-F115
Pre-commissioning of pipelines
DNV-RP-F116
Integrity management of submarine pipeline systems
DNV-RP-F118
Pipe girth weld automated ultrasonic testing system qualification and project specific
procedure validation
DNV-RP-F204
Riser fatigue
DNV-RP-N101
Risk management in marine and subsea operations
DNV-RP-N103
Modelling and analyses of marine operations
DNV-RP-O101
Technical documentation for subsea projects
DNV-RP-O501
Managing sand production and erosion
DNV-RP-0034
Steel forgings for subsea applications
DNV-RU-HSLC
Rules for classification: High speed and light craft
Standard — DNV-ST-F101. Edition August 2021, amended December 2021
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1.5.3 Other references
Table 1-3 Other references
Document code
Title
API RP 5L1
Recommended Practice for Railroad transportation of Line Pipe
API RP 5L3
Recommended Practice for Conducting Drop-Weight Tear Tests on Line Pipe
API RP 5LW
Recommended Practice for Transportation of Line Pipe on Barges and Marine Vessels
API RP 17N
Recommended Practice on Subsea Production System Reliability, Technical Risk, and Integrity
Management
API RP 2201
Safe Hot Tapping Practices in the Petroleum & Petrochemical Industries
API Spec 6A
Specification for Wellhead and Christmas Tree Equipment
API Spec 5LD
Specification for CRA Clad or Lined Steel Pipe
API Std 6FA
Standard for Fire Test for Valves
ASME B16.9
Factory-Made Wrought Buttwelding Fittings
ASME B31.3
Process Piping
ASME B31.4
Pipeline Transportation Systems for Liquid and Slurries
ASME B31.8
Gas Transmission and Distribution Systems
ASME BPVC-V
Boiler and Pressure Vessel Code Section V - Non-destructive Examination
ASME BPVC-VIII-1
Boiler and Pressure Vessel Code Section VIII - Div. 1 - Rules for Construction of Pressure Vessels
ASME BPVC-VIII-2
Boiler and Pressure Vessel Code Section VIII - Div. 2 - Rules for Construction of Pressure Vessels Alternative Rules
ASNT
American Society for Nondestructive Testing. Central Certification Program (ACCP).
ASTM A193
Standard Specification for Alloy-Steel and Stainless Steel Bolting for High Temperature or High
Pressure Service and Other Special Purpose Applications
ASTM A264
Standard Specification for Stainless Chromium-Nickel Steel-Clad Plate
ASTM A320
Standard Specification for Alloy-Steel and Stainless Steel Bolting for Low-Temperature Service
ASTM A370
Standard Test Methods and Definitions for Mechanical Testing of Steel Products
ASTM A388
Standard Practice for Ultrasonic Examination of Steel Forgings
ASTM A577
Standard specification for Ultrasonic Angle-Beam Examination of Steel Plates
ASTM A578
Standard Specification for Straight-Beam Ultrasonic Examination of Rolled Steel Plates for Special
Applications
ASTM A609
Standard Practice for Castings, Carbon, Low Alloy, and Martensitic Stainless Steel, Ultrasonic
Examination Thereof
ASTM A956
Standard Test Method for Leeb Hardness Testing of Steel Products
ASTM A961
Standard Specification for Common Requirements for Steel Flanges, Forged Fittings, Valves, and
Parts for Piping Applications
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Document code
Title
ASTM A1038
Standard Test Method for Portable Hardness Testing by the Ultrasonic Contact Impedance Method
ASTM B446
Standard Specification for Nickel-Chromium-Molybdenum-Columbium Alloy (UNS N06625), NickelChromium-Molybdenum-Silicon Alloy (UNS N06219), and Nickel-Chromium-Molybdenum-Tungsten
Alloy (UNS N06650) Rod and Bar
ASTM C33
Standards specification for concrete aggregates
ASTM D695
Standard Test Method for Compressive Properties of Rigid Plastics
ASTM E110
Standard Test Method for Rockwell and Brinell Hardness
ASTM E165
Standard Practice for Liquid Penetrant Examination for General Industry
ASTM E280
Standard Reference Radiographs for Heavy-Walled (4 1/2 to 12-in. (114 to 305-mm)) Steel
Castings
ASTM E309
Standard Practice for Eddy-Current Examination of Steel Tubular products Using Magnetic
Saturation
ASTM E317
Standard Practice for Evaluating Performance Characteristics of Ultrasonic Pulse-Echo Testing
Instruments and Systems Without the Use of Electronic Measurement Instruments
ASTM E426
Standard Practice for Electromagnetic (Eddy Current) Examination of Seamless and Welded
Tubular Products, Titanium, Austenitic Stainless Steel and Similar Alloys
ASTM E709
Standard Guide for Magnetic Particle Examination
ASTM E797
Standard Practice for Measuring Thickness by Manual Ultrasonic Pulse-Echo Contact Method
ASTM E1212
Standard Practice for establishing Quality Management Systems for Non-destructive Testing
Agencies
ASTM E1417
Standard Practice for Liquid Penetrant Examination
ASTM E1444
Standard Practice for Magnetic Particle Examination
ASTM E1820
Standard Test Method for Measurement of Fracture Toughness
ASTM G48
Standard Test Methods for Pitting and Crevice Corrosion Resistance of Stainless Steels and Related
Alloys by Use of Ferric Chloride Solution
AWS C5.3
Recommended Practices for Air Carbon Arc Gouging and Cutting
BS 7448
Fracture mechanics toughness tests. Method for determination of KIc, critical CTOD and critical J
values of metallic materials
BS 8571
Method of test for determination of fracture toughness in metallic materials using single edge
notched tension (SENT) specimens
BS 7910
Guide to methods for assessing the acceptability of flaws in metallic structures
BS PD 5500
Specification for unfired fusion welded pressure vessels
EN 1591-1
Flanges and their joints - Design rules for gasketed circular flange connections - Part 1:
Calculation
EN 1998
Eurocode 8: Design of structures for earthquake resistance - all parts
EN 10204
Metallic products - Types of inspection documents
EN 12668
Non destructive testing - Characterisation and verification of ultrasonic examination equipment- All
parts
Standard — DNV-ST-F101. Edition August 2021, amended December 2021
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Page 17
Document code
Title
EN 13445-3
Unfired pressure vessels - Part 3: Design
EN ISO 9606-1
Qualification testing of welders - Fusion welding - Part 1: Steels
EN ISO 14175
Welding consumables - Gases and gas mixtures for fusion welding and allied processes
IEC 61511
Functional safety - Safety Instrumented Systems for the Process Industry Sector - All parts
IMCA M140
Specification for DP capability plots
IMO Res. A.1047
(27)
Principles of safe manning
IMO MSC/Circ.645
Guidelines for Vessels with Dynamic Positioning Systems
ISO 148-1
Metallic materials – Charpy pendulum impact test - Part 1: Test method
ISO 377
Steel and steel products - Location and preparation of samples and test pieces for mechanical
testing
ISO 2400
Non-destructive testing - Ultrasonic testing - Specification for calibration block No. 1
ISO 3183
Petroleum and natural gas industries - Steel pipe for pipeline transportation systems
ISO 3452
Non-destructive testing – Penetrant testing – All parts
ISO 3690
Welding and allied processes – Determination of hydrogen content in arc weld metal
ISO 3834-2
Quality requirements for fusion welding of metallic materials – Part 2: Comprehensive quality
requirements
ISO 4063
Welding and allied processes – Nomenclature of processes and reference numbers
ISO 4126
Safety devices for protection against excessive pressure - All parts
ISO 4136
Destructive tests on welds in metallic materials – Transverse tensile test
ISO 5173
Destructive tests on welds in metallic materials – Bend tests
ISO 5178
Destructive tests on welds in metallic materials – Longitudinal tensile test on weld metal in fusion
welded joints
ISO 5817
Welding - Fusion-welded joints in steel, nickel, titanium and their alloys (beam welding excluded) Quality levels for imperfections
ISO 6507
Metallic materials – Vickers hardness test - All parts
ISO 6847
Welding consumables - Deposition of a weld metal pad for chemical analysis
ISO 6892
Metallic materials – Tensile testing - All parts
ISO 6947
Welding and allied processes – Welding positions
ISO 7005-1
Pipe flanges - Part 1: Steel flanges for industrial and general service piping systems
ISO 7539
Corrosion of metals and alloys - Stress corrosion testing - All parts
ISO 7963
Non-destructive testing – Ultrasonic testing – Specification for calibration block No. 2
ISO 8501-1
Preparation of steel substrates before application of paints and related products – Visual
assessment of surface cleanliness – Part 1: Rust grades and preparation grades of uncoated steel
substrates and of steel substrates after overall removal of previous coatings
ISO 9000
Quality management systems – Fundamentals and vocabulary
Standard — DNV-ST-F101. Edition August 2021, amended December 2021
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Page 18
Document code
Title
ISO 9001
Quality management systems – Requirements
ISO 9606-1
Qualification testing of welders - Fusion welding - Part 1: Steels
ISO 9712
Non-destructive testing – Qualification and certification of NDT personnel
ISO/TR 9769
Steel and iron – Review of available methods of analysis
ISO 9934
Non-destructive testing – Magnetic particle testing – All parts
ISO 10375
Non-destructive testing – Ultrasonic inspection – Characterization of search unit and sound field
ISO 10474
Steel and steel products - Inspection documents
ISO 10893
Non-destructive testing of steel tubes – All parts
ISO 11484
Steel products – Employer's qualification system for non-destructive testing (NDT) personnel
ISO 12135
Metallic materials - Unified method of test for determination of quasistatic fracture toughness
ISO 12715
Non-destructive testing -- Ultrasonic testing -- Reference blocks and test procedures for the
characterization of contact probe sound beams
ISO/TS 12747
Petroleum and natural gas industries – Pipeline transportation systems – Recommended practice
for pipeline life extension
ISO 13623
Petroleum and natural gas industries – Pipeline transportation systems
ISO 13847
Petroleum and natural gas industries – Pipeline transportation systems – Welding of pipelines
ISO 14284
Steel and iron – Sampling and preparation of samples for the determination of chemical
composition
ISO 14723
Petroleum and natural gas industries - Pipeline transportation systems - Subsea pipeline valves
ISO 14731
Welding coordination – Tasks and responsibilities
ISO 14732
Welding personnel -- Qualification testing of welding operators and weld setters for mechanized
and automatic welding of metallic materials
ISO 15156
Petroleum and natural gas industries - Materials for use in H2S-containing environments in oil and
gas production - All parts
ISO 15589
Petroleum and natural gas industries – Cathodic protection of pipeline transportation systems – All
parts
ISO 15590
Petroleum and natural gas industries – Induction bends, fittings and flanges for pipeline
transportation systems - All parts
ISO 15614-1
Specification and qualification of welding procedures for metallic materials – Welding procedure
test – Part 1: Arc and gas welding of steels and arc welding of nickel and nickel alloys
ISO 15618-2
Qualification testing of welders for underwater welding – Part 2: Diver-welders and welding
operators for hyperbaric dry welding
ISO 15649
Petroleum and natural gas industries – Piping
ISO 15653
Metallic materials - , Method of test for the determination of quasistatic fracture toughness of
welds
ISO 15741
Paints and varnishes - Friction-reducing coatings for the interior of on-and offshore steel pipelines
for non-corrosive gases
Standard — DNV-ST-F101. Edition August 2021, amended December 2021
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Page 19
Document code
Title
ISO 16708
Petroleum and natural gas industries – Pipeline transportation systems – Reliability-based limit
state methods
ISO 16828
Non-destructive testing - Ultrasonic testing - Time-of-flight diffraction technique as a method for
detection and sizing of discontinuities
ISO/IEC 17025
General requirements for the competence of testing and calibration laboratories
ISO 17636
Non-destructive testing of welds – Radiographic testing - All parts
ISO 17637
Non-destructive testing of welds – Visual testing of fusion-welded joints
ISO 17638
Non-destructive testing of welds – Magnetic particle testing
ISO 17640
Non-destructive testing of welds – Ultrasonic testing – Techniques, testing levels, and assessment
ISO 17643
Non-destructive testing of welds – Eddy current testing of welds by complex-plane analysis
ISO 19232
Non-destructive testing – Image quality of radiographs - All parts
ISO 19901-2
Petroleum and natural gas industries – Specific requirements for offshore structures – Part 2:
Seismic design procedures and criteria
ISO 21457
Petroleum, petrochemical and natural gas industries — Materials selection and corrosion control
for oil and gas production systems
ISO 21809
Petroleum and natural gas industries – External coatings for buried or submerged pipelines used in
pipeline transportation systems – All parts
ISO 22825
Non-destructive testing of welds – Ultrasonic testing – Testing of welds in austenitic steels and
nickel-based alloys
ISO 23936-2
Petroleum, petrochemical and natural gas industries – Non-metallic materials in contact with
media related to oil and gas production – Part 2: Elastomers
MSS SP-55
Quality standard for steel castings for valves, flanges, and fittings and other piping components Visual method for evaluation of surface irregularities
MSS SP-75
High-Strength, Wrought, Butt-Welding Fittings
NACE TM0177
Laboratory Testing of Metals for Resistance to Sulfide Stress Cracking and Stress Corrosion
Cracking in H2S Environments
NACE TM0284
Standard Test Method - Evaluation of Pipeline and Pressure Vessel Steels for Resistance to
Hydrogen-Induced Cracking
NORDTEST
NT Technical Report 394 (Guidelines for NDE Reliability Determination and Description, Approved
1998-04).
NORSOK L-005
Compact flanged connections
NORSOK N-006
Assessment of structural integrity for existing offshore load-bearing structures
NORSOK U-009
Life extension for subsea systems
NORSOK Y-002
Life extension for transportation systems
NS 477
Welding inspectors - Tasks, education and certification
Standard — DNV-ST-F101. Edition August 2021, amended December 2021
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1.6 Definitions and abbreviations
1.6.1 Definition of verbal forms
The verbal forms defined in Table 1-4 are used in this document.
Table 1-4 Definition of verbal forms
Term
Definition
shall
verbal form used to indicate requirements strictly to be followed in order to conform to the
document
should
verbal form used to indicate that among several possibilities one is recommended as
particularly suitable, without mentioning or excluding others
may
verbal form used to indicate a course of action permissible within the limits of the document
agreement, by agreement
unless otherwise indicated, this means agreed in writing between the manufacturer/
contractor and purchaser
1.6.2 Definition of terms
The terms defined in Table 1-5 are used in this document.
Table 1-5 Definition of terms
Term
Definition
abandonment
activities associated with taking a pipeline permanently out of operation
Different terminology may be used to describe this activity subject to local regulatory and/or
company requirements and de-commissioning may be used in some regions.
accumulated plastic strain
sum of plastic strain increments, irrespective of sign and direction after manufacturing of the
line pipe
additional requirement
requirement that applies to this standard, additional to other referred standards
as-built survey
survey of the installed and completed pipeline system that is performed to verify that the
completed installation work meets the specified requirements and document deviations from
the original design, if any
as-laid survey
survey performed either by continuous touchdown point monitoring or by a dedicated vessel
during installation of the pipeline
assembly, in-line
pipeline components' buckle and fracture arrestors, PLEMs and PLETs, which are an
integrated part of the pipeline and connected or welded to the pipeline during installation
assembly, pipeline
riser, pipe strings for e.g. reeling or towing, spools which are welded onshore, see [8.6]
assessment
action of assessing something
annual probability
probability of an event occuring during a one-year period
atmospheric zone
part of the pipeline system above the splash zone
battery limit
defined boundary between two areas of responsibility
Standard — DNV-ST-F101. Edition August 2021, amended December 2021
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Term
Definition
buckling, global
buckling mode, like a bar in compression, which involves a substantial length of the pipeline,
usually several pipe joints and not gross deformations of the cross-section; upheaval
buckling is an example thereof, see [5.4.7]
buckling, local
buckling mode confined to a short length of the pipeline causing gross changes of the crosssection; collapse, localized wall wrinkling and kinking are examples thereof, see [5.4.3]
buckling, propagation
propagating buckle initiated by a deformation of the pipeline and driven by external over
pressure
characteristic load
reference value of a load to be used in the determination of load effects
The characteristic load is normally based upon a defined fractile in the upper end of the
distribution function for load, see [4.7].
characteristic resistance
reference value of structural strength to be used in the determination of the design strength
The characteristic resistance is normally based upon a defined fractile in the lower end of the
distribution function for resistance, see [5.3.2].
clad pipe
pipe with internal corrosion resistant liner where the bond between the backing steel, line
pipe and cladding material is metallurgical
clamp
circumferential structural element, split into two or more parts designed to hold pieces
together, such as two pipe half-shells, to facilitate repair
coating, concrete
weight coating for anti-buoyancy or protection
Not covered by the term line pipe coating.
coating, field joint
refers to single or multiple layers of coating applied to protect girth welds and the associated
cut-back of the line pipe coating, irrespective of whether such coating is actually applied in
the field or in a factory
coating, line pipe
also referred to as factory coating or parent coating, refers to factory-applied external
coating systems, mostly multiple-layer, with a total thickness of some millimetres and
a corrosion protection function, either alone or in combination with a thermal insulation
function
Some coating systems may further include an outer layer for mechanical protection, primarily
during laying and any rock dumping or trenching operations.
coating field repairs
repairs of factory coating performed in the field, typically by the field joint coating contractor
code break
point or cross-section on the pipeline where one set of specifications applies on one side and
another set on the other side
coiled tubing
continuously-milled tubular product manufactured in lengths that require spooling onto a
take-up reel during the primary milling or manufacturing process
collapse pressure
characteristic resistance against external over-pressure, see [5.4.4]
commissioning
activities associated with the initial filling of the pipeline system with the fluid to be
transported, part of the operational phase
concept development
phase
period which includes business evaluations, the collecting of data and technical early phase
considerations
condition load effect
factor
load effect factor included in the design load effect to account for specific load conditions, see
Table 4-5
connector
mechanical device used to connect two hubs to create a structural joint resisting applied
loads and preventing leakage
Standard — DNV-ST-F101. Edition August 2021, amended December 2021
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Term
Definition
construction phase
the period that includes manufacturing, fabrication and installation activities
contractor
party contractually appointed by the purchaser to fulfil all or any of the activities associated
with design, construction, operation and abandonment
corrosion allowance
extra wall thickness added during the design to compensate for any reduction in wall
thickness by internal or external corrosion during operation, see [6.4.2]
corrosion control
all relevant measures for corrosion protection, including inspection and monitoring of
corrosion
corrosion protection
use of corrosion resistant materials, corrosion allowance and various techniques for corrosion
mitigation
coupling
mechanical device to connect two bare pipes to create a structural joint resisting applied
loads and preventing leakage
cross over pressure
the pressure required to continue a propagating buckle across a buckle arrestor This may not
buckle the buckle arrestor, still allow the buckle to continue.
decommissioning
activities associated with taking the pipeline temporarily out of service
Different terminology may be used to describe this activity subject to local regulatory and/or
company requirements.
dent
depression which produces a gross disturbance in the curvature of the pipe wall
design
all related engineering to design the pipeline, including structural, material and corrosion
design case
characterization of different load categories, see [4.1.5]
design life
initially planned time period from initial installation until abandonment of the equipment or
system
The original design life may be extended after a re-qualification.
design premises
set of project specific design data and functional requirements which are not specified or
which are left open in the standard to be prepared prior to the design phase
Standard — DNV-ST-F101. Edition August 2021, amended December 2021
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Term
design pressure
Definition
maximum internal pressure during normal operation, referred to the same reference
elevation as the incidental pressure, see Figure 1-1 and [3.4.2]
Figure 1-1 Pressure definitions
design phase
the period when detailed specifications that emphasize the physical solution to the user's
information technology needs are developed
diameter
circumference divided by π except when measuring the ovality
dynamic riser
production risers tied back to floating structures (ISO 13628-1)
element
structural element in an assembly, e.g. outer and inner pipe, bulkhead of a pipe-in-pipe
system
engineering critical
assessment
fracture mechanics assessment of the acceptability of flaws in metallic materials
erosion
material loss due to repeated impact of sand particles or liquid droplets
fabrication
activities related to the assembly of objects with a defined purpose in a pipeline system
fabrication factor
factor on the material strength to compensate for material strength reduction in the hoop
direction from cold forming during manufacturing of the line pipe, see Table 5-4
fabricator
party performing the fabrication
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Term
failure
Definition
event affecting a component or system and causing one or both of the following effects:
— loss of component or system function
— deterioration of functional capability to such an extent that the safety of the installation,
personnel or environment is significantly reduced
fatigue
cyclic loading causing degradation of the material
fittings
elbows, caps, tees, single or multiple extruded headers, reducers and transition sections
flange
collar at the end of a pipe usually provided with holes in the pipe axial direction for bolts to
permit other objects to be attached to it
flaw
imperfection or discontinuity that may be detectable by NDT and is not necessarily rejectable
fluid categorization
categorization of the transported fluid according to hazard potential, see Table 2-1
fractile
p-fractile, or percentile, given as:
where F is the distribution function for the fractile value xp
golden weld
girth weld that is not subjected to a system pressure test
gross error
mistake, often human, that has significant consequences
heat
metal produced by a single cycle of a batch melting process
hub
parts in a connector joined by a clamp
hydro- or hydrostatic test
pressure
see pressure, mill test
hydrogen induced
cracking
internal cracking of rolled materials due to a build-up of hydrogen pressure in micro-voids,
also referred to as stepwise cracking
hydrogen induced stress
cracking
cracking that results from the presence of hydrogen in a metal while subjected to tensile
residual or applied stresses
The source of hydrogen may be welding, corrosion, cathodic protection, electroplating or
some other electrochemical process. Crack growth proceeds by a hydrogen embrittlement
mechanism at the crack tip, i.e. the bulk material is not necessarily embrittled by hydrogen.
Hydrogen induced stress cracking by corrosion in the presence of hydrogen sulphide is
referred to as sulphide stress cracking (SSC).
hydrostatic test
hydrostatic pressure tests in general, i.e. with water, in some standards used for the mill
pressure test
incidental pressure
maximum internal pressure the pipeline or pipeline section is designed to withstand during
any incidental operating situation, referred to a specified reference elevation, see Figure 1-1
and [3.4.2]
-2
This pressure is characterized by a probability of being exceeded in a year of less than 10 .
initiation pressure
external over-pressure required to initiate a propagating buckle from an existing local buckle
or dent, see [5.4.5]
inner pipe
inner pipe in a pipe-in-pipe system
The purpose of the inner pipe is to convey the pipeline content.
in-service file
system for collection of historical data, consisting of documents, data files and databases
Standard — DNV-ST-F101. Edition August 2021, amended December 2021
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Term
Definition
inspection
activities such as measuring, examining, weighing, testing or gauging one or more
characteristics of a product or service and comparing the results with specified requirements
to determine conformity
installation (activity)
operations related to installing the equipment, pipeline or structure, e.g. pipeline laying, tiein, piling of structure etc.
installation (object)
see offshore installation
installation manual
document prepared by the contractor to describe and demonstrate that the installation
method and equipment used by the contractor will meet the specified requirements and that
the results can be verified
integrity (pipeline)
ability of the submarine pipeline system to operate safely and withstand the loads imposed
during the design life
jointer
two lengths of pipe welded together by the manufacturer to build up one complete pipe joint,
typically 12.2 m (≈ 40 ft)
J-R curve
plot of resistance to stable crack growth for establishing crack extension
limit state
state beyond which the structure no longer satisfies the requirements
The following limit state categories are of relevance for pipeline systems:
— serviceability limit state (SLS): a condition which, if exceeded, renders the pipeline
unsuitable for normal operations. Exceedance of a serviceability limit state category shall
be evaluated as an accidental limit state
— ultimate limit state (ULS): a condition which, if exceeded, compromises the integrity of
the pipeline
— fatigue limit state (FLS): an ULS condition accounting for accumulated cyclic load effects
— accidental limit state (ALS): an ULS condition due to accidental (infrequent) loads.
line pipe
defined length of welded or seamless straight pipe with uniform thickness, typically ≈ 12.2 m
(40 ft)
Standard — DNV-ST-F101. Edition August 2021, amended December 2021
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Term
line pipe manufacturing
process
Definition
Line pipes may be manufactured as seamless or welded pipes
Seamless (SML) pipes are manufactured from billets and typically formed by piercing and
mandrel rolling and have therefore no longitudinal weld.
Welded pipes are manufactured from rectangular plates or strips from coil. They are referred
to by the following terms, based on the cold forming processes and welding processes listed
below:
— UO pipes are first crimped along the longitudinal edges and then plastically formed into a
'U' shape by a U-press, followed by further forming into an 'O' shape. Subsequently, the
longitudinal edges are pressed together and welded by a submerged arc welding (SAW)
process, also referred to as SAWL pipes where L stands for longitudinal.
— UOE pipes are fabricated in the same way as the UO pipes, but are in addition
mechanically expanded after welding. Also referred to as SAWL pipes.
— JCO pipes are formed incrementally by a 'knife' along the longitudinal edge of the plate,
moving stepwise from one side of the plate to the other. Referred to as SAWL pipes.
— JCOE pipes are fabricated in the same way as the JCO pipes but are in addition
mechanically expanded after welding. Also referred to as SAWL pipes.
— TRB (three roll bending) pipes are formed from one longitudinal edge to the other by
three rollers along the whole length of the pipe. This is done incrementally by rolling the
plate on and off until a pipe has eventually been formed. Referred to as SAWL pipes.
— Coiled pipes are formed continuously from strip on coil into a pipe shape. The longitudinal
seam weld may be welded by high frequency welding (HFW), either by electric resistance
welding (ERW) or electric induction welding (EIW), in a continuous process and further
the pipe is coiled onto a large drum for small dimensions, also referred to as tubing.
— HFW is also applied for larger pipe diameters. However, in this case the pipes are cut into
long straight pipes, typically 12 m or 18 m.
— Spiral pipes are formed from strip on coil into a spiral shape constituting a pipe. The strip
is submerged arc welded. The process is referred to as the submerged arc welding helical
(SAWH) process.
lined pipe
pipe with internal corrosion resistant liner with a mechanical bond between the backing steel
and liner material
load
any action causing stress, strain, deformation, displacement, motion, etc. to the equipment
or system
load, accidental
loads caused by abnormal and unplanned conditions characterized by a probability of
-2
occurrence within a year of less than 10 , see [4.6.1.1] and [5.4.10]
load, construction
loads caused by the construction of the submarine pipeline system
Shall be split into functional and environmental loads.
load, environmental
loads caused by the surrounding environment on the pipeline system if not defined as
functional or accidental loads, see [4.3.1.1]
load, functional
loads caused by the physical existence of the pipeline system and its intended use, see
[4.2.1.1]
load, hydrodynamic
environmental loads caused by the relative motion between the pipe and the surrounding
water flow, see [4.3.3.1]
load, interference
loads caused by third party activities
Typical interference loads include trawl interference, anchoring, vessel impacts and dropped
objects, see [4.5.1.1].
load categories
functional load, environmental load, interference load or accidental load, see [4.1]
Standard — DNV-ST-F101. Edition August 2021, amended December 2021
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Term
Definition
load effect
resulting stress, strain or cross-sectional loads arising in response to applied loads such as
weight, pressure, drag or thermal expansion
load effect combinations
factorized sum of different load effect types to form a design load effect, see [4.7.3]
load effect factor
partial safety factor by which the characteristic load effect is multiplied to obtain the design
load effect, see [4.7.3]
load scenarios
combination of different loads acting simultaneously, constituting a design scenario, see [4.1]
local pressure
the internal pressure at any point in the pipeline system or pipeline section for the
corresponding design pressure, incidental pressure or test pressure adjusted for the column
weight, see [4.2.2]
location class
geographic area of pipeline system, see Table 2-2
lot
components of the same size and from the same heat, the same heat treatment batch
manufacture
making of articles or materials, often in large volumes
In relation to pipelines, refers to activities for the production of line pipe, anodes and other
components and the application of coating, performed under contracts from one or more
contractors.
manufacturer
party contracted to be responsible for planning, execution and documentation of
manufacturing
manufacturing procedure
specification (MPS)
manual prepared by the manufacturer to demonstrate how the specified properties may be
achieved and verified through the proposed manufacturing route
maximum allowable
incidental pressure
maximum internal pressure at which the pipeline system shall be operated during an
incidental operation situation, given by the maximum incidental pressure less the positive
tolerance of the pipeline safety system
maximum allowable
operating pressure
maximum pressure at which the pipeline system shall be operated during normal operation
given by the design pressure less the positive tolerance of the pipeline control system
maximum design
temperature
highest possible temperature profile to which the equipment or system may be exposed
during installation and operation (100-year value)
material resistance factor
partial safety factor transforming a characteristic resistance to a lower fractile resistance, see
Table 5-1
material strength factor
factor for determining the characteristic material strength reflecting the confidence in the
yield stress, see Table 5-3
mill pressure test
hydrostatic strength test performed at the mill, see [5.2.2] and [D.2.1.5]
mill test pressure
test pressure applied to pipe joints and pipeline components upon completion of manufacture
and fabrication, see [5.2.2]
minimum design
temperature
lowest possible temperature profile to which the component or system may be exposed
during installation and operation (100-year value)
This may be applied locally, see [4.2.1.6].
minimum wall thickness
specified non-corroded pipe wall thickness of a pipe minus the manufacturing tolerance
modified requirement
requirements that apply to this standard, modified compared to other referenced standards
Standard — DNV-ST-F101. Edition August 2021, amended December 2021
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Term
Definition
nominal failure probability
probability of structural failure due to natural uncertainties as reflected in structural reliability
analyses
Gross errors are not included, see [2.3.5].
nominal outside diameter
specified outside diameter
nominal pipe wall
thickness
specified non-corroded pipe wall thickness of a pipe
nominal strain
total engineering strain not accounting for local strain concentration factors
nominal plastic strain
nominal strain minus the linear strain derived from the stress-strain curve, see Figure 1-2
non-welded connection
leak tight connection by sealing surfaces of two objects pressed together to create a
structural joint resisting applied loads and preventing leakage
notch
machined geometry in a test specimen that, exposed to the fatigue load, initiates a crack like
flaw for fracture toughness testing
operation, incidental
conditions that are not part of the normal operation of the equipment or system
In relation to pipeline systems, incidental conditions may lead to incidental pressures, e.g.
pressure surges due to the sudden closing of valves, or failure of the pipeline control system
and activation of the pipeline safety system.
operation, normal
conditions that arise from the intended use and application of the equipment or system,
including associated condition and integrity monitoring, maintenance, repairs, etc.
In relation to pipelines, this should include steady flow conditions over the full range of flow
rates, as well as possible packing and shut-in conditions where these occur as part of the
routine operation.
operation phase
period when the pipeline operates with the intended purpose starts with filling the pipeline
with the intended fluid
The operation phase may also include modifications, re-qualifications and de-commissioning.
operational temperature
representative temperature profile(s) during operation
operator (pipeline)
party ultimately responsible for the concept development, design, construction and operation
of the pipeline system
The operator may change between phases.
out of roundness
deviation of the line pipe perimeter from a circle, expressed as ovalization or local out of
roundness
outer pipe
outer pipe in a pipe-in-pipe system
The main purpose of this pipe is to protect the annulus, keep it dry and not expose it to
excessive pressure.
ovalization
deviation of the perimeter from a circle
This has the form of an elliptic cross-section.
overbend
length of the pipeline supported by the vessel/ramp/stinger where the slope is transitioning
from a firing line to a departure angle where the pipe leaves the vessel/ramp/stringer
parameter operating
envelope
limitations of the operating parameters in the pipeline control system
This includes all relevant parameters and links between these, including minimum values if
relevant.
Standard — DNV-ST-F101. Edition August 2021, amended December 2021
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Term
Definition
parameter safety
envelope
limitations of the operating parameters in the pipeline safety system
partial safety factor
factor by which the characteristic value of a variable is modified to give the design value
A partial safety factor may be: a load effect, condition load effect, material resistance or
safety class resistance factor, see [5.3].
pipe joint
defined length of pipe, typically ≈ 12.2 m (40 ft)
pipeline component
pressure-containing part of a pipeline system that is not made of line pipe or weld through
which the main flow flows and protection, such as fittings, flanges, valves, mechanical
connectors, CP isolation joints, anchor flanges, pig traps, repair clamps and repair couplings
pipeline configuration
survey
survey to determine the position, configuration and condition of the pipeline and its
components
pipeline control system
basic process control system that ensures the operating parameters are within the operating
parameter envelope
pipeline integrity
management
combined process of threat identification, risk assessments, planning, monitoring, inspection,
maintenance etc. to maintain pipeline integrity
pipeline safety system
system as per IEC 61511 that ensures the operating parameters are within the safety
parameter envelope
The safety parameters may be, but are not limited to, flow, internal pressure, temperature or
composition.
pipeline system
pipeline with compressor or pump stations, pipeline control stations, metering, tankage,
a supervisory control and data acquisition system (SCADA), safety systems, corrosion
protection systems, and any other equipment, facility or building used in the transportation
of fluids
See also submarine pipeline system.
pipeline walking
accumulation of incremental axial displacement of pipeline due to pressure and temperature
cycles from start-up, shut-down and axial friction
positioning/heading
keeping
maintaining a desired position/heading within the normal execution of the control system and
environmental conditions
position/heading
reference system
all hardware, software and sensors that supply the information and/or corrections necessary
to give a positioning/heading reference
pre-commissioning
activities after tie-in/connection and prior to commissioning, including system pressure
testing, de-watering, cleaning and drying
pressure test
see system pressure test
progressive failure
failure that leads to another failure with escalating consequences
propagating pressure
lowest pressure required for a propagating buckle to continue to propagate, see [5.4.5]
pup piece
extra line pipe piece added to a component to build up a certain overall length, typically for
construction and/or fabrication purposes
purchaser
owner or another party acting on the owner's behalf who is responsible for procuring
materials, components or services intended for the design, construction or modification of an
installation or pipeline
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Term
quality assurance
Definition
planned and systematic actions necessary to provide adequate confidence that a product or
service will satisfy given quality requirements
(The quality assurance actions of an organization are described in a quality manual stating
the quality policy and containing the necessary procedures and instructions for planning and
performing the required actions.)
quality control
internal systems and practices, including direct inspection and materials testing, used by
manufacturers to ensure that their products meet the required standards and specifications
quality plan
document setting out the specific quality practices, resources and sequence of activities
relevant to a particular product, project or contract
A quality plan usually makes reference to the part of the quality manual, e.g. procedures and
work instructions, applicable to the specific case.
ratcheting
accumulated deformation during cyclic loading, especially for diameter increase, see [5.4.13]
Does not include so called pipeline walking.
reassessment
assessment based on the design basis complemented by updated input from e.g. inspection
reliability
probability that a component or system will perform its required function without failure,
under stated conditions of operation and maintenance and during a specified time interval
re-qualification
re-assessment of a design due to modified design premises and/or sustained damage
resistance
capability of a structure, or part of a structure, to resist load effects, see [5.3.2]
riser
connecting piping or flexible pipe between a submarine pipeline on the seabed and
installations above water
The riser extends to the above sea emergency isolation point between the import/export line
and the installation facilities, i.e. riser ESD valve.
risk
qualitative or quantitative likelihood of an accidental or unplanned event occurring,
considered in conjunction with the potential consequences of such a failure
In quantitative terms, risk is the quantified probability of a specified failure mode times its
quantified consequence.
safety class
a concept adopted to categorize and quantify the significance of the pipeline system with
respect to the consequences of failure, see [2.3.4]
safety class resistance
factor
partial safety factor which transforms the lower fractile resistance to a design resistance
reflecting the safety class, see Table 5-2
sagbend
the length of the pipeline, spanning between the touchdown point on the seabed and the
pipeline inflection point, or the departure point on the pipeline installation vessel/ramp/
stringer if the pipeline does not have an inflection point
shut-in pressure
maximum pressure that can be attained at the wellhead during closure of valves closest to
the wellhead (wellhead isolation), including pressure transients due to the valve closing
single event
straining in one direction
specified minimum tensile
strength
minimum tensile strength specified by this standard
specified minimum yield
stress
minimum yield stress specified by this standard
For the supplementary requirement U, this corresponds to a statistical value equal to or lower
than the mean minus three standard deviations.
For the supplementary requirement U, this corresponds to a statistical value equal to or lower
than the mean minus two standard deviations.
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Term
Definition
splash zone
external surfaces of a structure or pipeline that are periodically in and out of the water by the
influence of waves and tides
spool
prefabricated assembly of pipe joints which is used to connect a pipeline to another subsea
structure, e.g. a manifold, PLET, tee or riser, or replaces a part of pipeline
stress-strain curve
uni-axial material characterization, given as engineering stress-strain or true stress-strain
when a reduction in the cross-sectional area is included in the force-to-stress conversion, see
Figure 1-2
Figure 1-2 Stress-strain curve and definitions
stress/strain
concentration factor
often defined as the ratio of the peak stress/strain in the body to a reference stress/strain.
In general it is an adjustment factor to the load effect, such as the moment, stress or strain,
to reflect aspects not captured in the load effect calculation tool to achieve a load effect
assumed in the applied limit state
Examples are S-N curves where the stress concentration factor depends on the applied
S-N curve. Stress concentration factors are often applied in the linear range while strain
concentration factors are applied in the non-linear range, which makes strain concentration
factor load dependent.
submarine pipeline
part of a submarine pipeline system which, except for pipeline risers, is located below the
water surface at maximum tide
The pipeline may be resting wholly or intermittently on, or buried below, the seabed.
submarine pipeline
system
system that extends to the first weld beyond:
— the first valve, flange or connection above water on the platform or floater
— the connection point to the subsea installation, i.e. piping manifolds are not included
— the first onshore valve, flange, connection or insulation joint, unless otherwise specified
by the on-shore legislation
The component above the valve, flange, connection or insulation joint includes any pup
pieces, i.e. the submarine pipeline system extends to the weld beyond the pup piece.
submerged zone
part of the pipeline system or installation below the splash zone, including buried parts
supplementary
requirements
requirements for material properties of line pipe that are additional and intended to apply to
pipe used for specific applications
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Term
Definition
system effects
system effects are present when potential structural failure occurs in connection with the
weakest pipe section, see [4.7.3]
system pressure test
final test of the complete pipeline system, see [5.2.2]
system test pressure
internal pressure applied to the pipeline or pipeline section during testing on completion of
installation work to test the pipeline system for tightness, normally performed as hydrostatic
testing, see [5.2.2]
target nominal failure
probability
nominal acceptable probability of structural failure
technology qualification
process of providing the evidence that technology will function within specified limits with an
acceptable level of confidence
test unit
prescribed quantity of pipe that is made to the specified outer diameter and specified wall
thickness, by the same pipe-manufacturing process, from the same heat, and under the
same pipe-manufacturing conditions
threats
indication of impending danger or harm to the pipeline system
tide
the rise and fall of sea levels caused by the combined effects of the gravitational forces
exerted by the moon and sun and the rotation of the earth
ultimate tensile strength
measured maximum stress defined as Rm
verification
confirmation, through the provision of objective evidence, that specified requirements have
been fulfilled (ISO 9000:2015)
weld defect
one or more flaws whose aggregate size, shape, orientation, location or properties do not
meet specified acceptance criteria and are rejectable
weld, girth
circumferential weld between two pipe joints including expansion loops, pipe strings for
reeling or towing and tie-in welds
work
all activities to be performed within relevant contract(s) issued by the owner, operator,
contractor or manufacturer
yield stress
measured tensile stress at 0.5% strain, defined as Rt0.5
100-year load effect
load effect that has a probability of being exceeded within one year equal to 10
Gross errors are not included, see [2.3.5].
-2
1.6.3 Abbreviations
The abbreviations described in Table 1-6 are used in this document.
Table 1-6 Abbreviations
Abbreviation
Description
ALS
accidental limit state
AR
additional requirement to the stated ISO standard
API
American Petroleum Institute
APS
application procedure specification
ASD
allowable stress design
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Abbreviation
Description
ASME
American Society of Mechanical Engineers
ASTM
American Society for Testing and Materials
AUT
automated ultrasonic testing
AWS
American Welding Society
BM
base material
BS
British Standard
CE
carbon equivalent
C-Mn
carbon manganese
CMOD
crack mouth opening displacement
CP
cathodic protection
CRA
corrosion resistant alloy
CTOD
crack tip opening displacement
CVN
Charpy v-notch
DAC
distance amplitude correction
DC
displacement controlled
DFI
design, fabrication and installation
DGS
distance gain-size
DP
dynamic positioning
DWTT
drop weight tear testing
EBW
electron beam welded
EC
eddy current testing
ECA
engineering critical assessment, a fracture assessment
EDI
electronic data interchange
EMS
electro magnetic stirring
EN
European Standard
ERW
electric resistance welding
ESD
emergency shut down
FBH
flat bottom hole
FEED
front end engineering design
FJC
field joint coating
FLS
fatigue limit state
FMEA
failure mode effect analysis
FTA
flowline termination assembly
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Abbreviation
Description
G-FCAW
gas-flux core arc welding
GMAW
gas metal arc welding
HAT
highest astronomical tide
HAZ
heat affected zone
HAZOP
hazard and operability study
HFW
high frequency welding
HIPPS
high integrity pressure protection system
HIC
hydrogen induced cracking
HISC
hydrogen induced stress cracking
ILTA
in-line tea assembly
IM
installation manual
IMCA
International Marine Contractors Association
IMO
International Maritime Organization
ISO
International Organization for Standardization
ITP
inspection and testing plan
J-R curve
plot of resistance to stable crack growth for establishing crack extension
KV
Charpy (kinetic energy) value
KVL
Charpy value in pipe longitudinal direction
KVT
Charpy value in pipe transversal direction
LAT
lowest astronomic tide
LC
load controlled
LBW
laser beam welded
LBZ
local brittle zones
LRFD
load and resistance factor design
M/A
martensitic/austenite
MAIP
maximum allowable incidental pressure
MAOP
maximum allowable operating pressure
MDS
material data sheet
MPQT
manufacturing procedure qualification test
MPS
manufacturing procedure specification
MR
modified requirement to the stated ISO standard
MSA
manufacturing survey arrangement
MT
magnetic particle testing
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Abbreviation
Description
MWP
multiple welding process
N
normalized
NACE
National Association of Corrosion Engineers
NDT
non-destructive testing
NORSOK
NORsk SOkkels Konkurransefortrinn (Norwegian Shelf's Competitive Position)
NS
Norsk Standard
OHTC
overall heat transfer coefficient
P
production
PCS
pipeline control system
PFD
probability of failure on demand
PIM
pipeline integrity management
PiP
pipe-in-pipe
PPT
pre-production trial
PRE
pitting resistance equivalent
PRL
primary reference level
PSS
pipeline safety system
PT
penetrant testing
PTFE
poly tetra fluoro ethylene
PVC
pressure vessel codes
PWHT
post weld heat treatment
pWPS
preliminary welding procedure specification
PQT
procedure qualification trial
Q
qualification
QA
quality assurance
QC
quality control
QP
quality plan
QRA
quantitative risk assessment
QT
quenched and tempered
RGD
rapid gas decompression
ROV
remotely operated vehicle
RT
radiographic testing
SAW
submerged arc-welding
SC
safety class
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Abbreviation
Description
SCF
stress concentration factor
SCM
Supplementary Cementitious Materials
SCR
steel catenary riser
SENB
single edge notched bend fracture mechanics specimen
SENT
single edge notched tension fracture mechanics specimen
SFC
steel forging class
SLS
serviceability limit state
SMAW
shielded metal arc welding
SMLS
seamless pipe
SMTS
specified minimum tensile strength
SMYS
specified minimum yield stress
SN
surface notch
S-N
stress versus number of cycles to failure
SNCF
strain concentration factor
SRA
structural reliability analysis
SSC
sulphide stress cracking
ST
surface testing
TCM
two curve method
TMCP
thermo-mechanical controlled process
TOFD
time of flight diffraction
UEL
uniform elongation length, see Table 6-1
ULS
ultimate limit state
UT
ultrasonic testing
UTS
ultimate tensile strength
VT
visual testing
WM
weld metal
WAT
wax appearance temperature
WPQT
welding procedure qualification test
WPS
welding procedure specification
YS
yield stress
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1.6.4 Symbols – Latin characters
= cross-sectional area
= pipe external cross-sectional area
= pipe internal cross-sectional area
= pipe steel cross-sectional area
B
D
= specimen width
= nominal outside diameter
= Miner’s sum
DFF
= design fatigue factor
=
D–2tnom nominal internal diameter
= greatest measured inside or outside diameter
= smallest measured inside or outside diameter
E
= Young's modulus
= characteristic material burst strength, minimum of fy and fu/1.15
= characteristic lower bound tensile strength to be used in design
= derating on tensile stress to be used in design
= characteristic lower bound yield stress to be used in design
= derating on yield stress to be used in design
= lower bound yield stress of CRA liner or clad to be used in design
g
H
= gravity acceleration
= residual lay tension
= height of weld bead including misalignment
= elevation at pressure point
= permanent plastic dent depth
= elevation at pressure reference level
= significant wave height
ID
= nominal inside diameter
= number of stress blocks
= load effect, length of pipe, lined pipe
= moment
= axial force in pipe wall (true force) (tension is positive) or number of load effect cycles
= number of stress blocks
= number of stress cycles to failure at constant amplitude
O
= ovality
= pressure containment resistance
= characteristic collapse pressure, Equation (5.13)
= design pressure
= probability of damaging event i
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= external pressure
= elastic collapse pressure
= failure probability
= target nominal failure probability
= characteristic internal pressure
= incidental pressure
= initiation pressure
= local design pressure
= local incidental pressure
= local test pressure (system test)
= mill test pressure
= plastic collapse pressure
= propagating pressure
= propagating buckle capacity of infinite buckle arrestor
= system test pressure
= crossover pressure
R
= global bending radius of pipe, reaction force or resistance
= tensile strength
= strength equivalent to a permanent elongation of x% (actual stress)
= strength equivalent to a total elongation of x% (actual stress)
S
t
= effective axial force (tension is positive)
= nominal wall thickness of pipe (un-corroded)
= nominal wall thickness of backing steel pipe of a lined or clad pipe, same as t
= characteristic thickness to be replaced by t1 or t2 as relevant
= corrosion allowance
= thickness of liner or clad
= erosion allowance thickness
= fabrication thickness tolerance
= measured minimum thickness
= minimum wall thickness, similar to t1
= nominal wall thickness of pipe (un-corroded)
= pipe wall thickness
T
= temperature
= contingency time for operation/ceasing operation
= maximum design temperature
= minimum design temperature
= planned operational period
= reference period for operation/ceasing operation
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= planned time to cease operation
= time between generated weather forecasts
= testing temperature
W
= section modulus or specimen thickness
= submerged weight.
1.6.5 Symbols – Greek characters
= thermal expansion coefficient
= characteristic flow stress ratio
= fabrication factor
= girth weld factor (strain resistance)
= strain hardening
= mill pressure test factor
= pressure factor used in displacement controlled capacity
= plastic moment reduction factor for point loads
= system pressure test factor
= material strength factor
= factor used in combined loading criteria
= strain
= characteristic bending strain resistance
= accumulated plastic strain resistance
= total nominal longitudinal strain
= plastic strain
= residual strain range
= load effect factor for accidental load
= condition load effect factor
= load effect factor for environmental load
= load effect factor for functional load
= incidental to design pressure ratio
= material resistance factor
= pressure factor used in combined loading criteria
= safety factor for residual strain
= safety class resistance factor for limit state i (PC, LB, DC)
= design factor
= curvature
= Poisson’s ratio
= friction coefficient
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= density pipeline content
= density pipeline content during system pressure test
= standard deviation of a variable (e.g. thickness)
= equivalent stress, Von Mises
= hoop stress
= longitudinal/axial stress
= tangential shear stress.
1.6.6 Subscripts
The subscripts described in Table 1-7 are used in this document.
Table 1-7 Description of subscripts
Subscript
Description
A
accidental load
bs
backing steel, i.e. the CMn pipe of a lined or clad pipe
c
characteristic resistance
com
combined, contribution from backing steel and clad/liner
CRA
the CRA liner or clad
d
design value
E
environmental load
e
external
el
elastic
F
functional load
h
circumferential direction (hoop direction)
i
internal
L
axial (longitudinal) direction
M
moment
mpt
mill pressure test
p
plastic
R
radial direction
Rd
design resistance (i.e. including partial resistance factors)
s
steel
Sd
design load (i.e. including load effect factors)
spt
system pressure test
U
ULS
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Subscript
X
Description
crossover (buckle arrestors)
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