Bsi bs en 12732 2013 + a1 2014

EN 287-1, Qualification test of welders — Fusion welding — Part 1: Steels EN 1418:1997, Welding personnel — Approval testing of welding operators for fusion welding and resistance weld

BSI Standards Publication

Gas infrastructure — Welding steel pipework — Functional requirements

This British Standard is the UK implementation of EN 12732:2013+A1:2014

It supersedes BS EN 12732:2013 which is withdrawn

The UK committee voted against this standard for several reasons, particularly because of technical differences with a long established

UK gas industry standard for welding procedures, BS 4515, and on the requirements for the qualification of welding personnel Also several improvements requested by the UK gas industry stakeholders to the draft EN 12732 were not accepted A full set of UK comments may be obtained from BSI Committee Service Centre The UK will attempt again

to have improvements made when this standard is revised The UK committee also acknowledges that despite voting against this standard,

it can still be used by other UK industries

The UK participation in its preparation was entrusted to Technical Committee GSE/33, Gas supply

A list of organizations represented on this committee can be obtained

on request to its secretary

This publication does not purport to include all the necessary provisions

of a contract Users are responsible for its correct application

© The British Standards Institution 2014

Published by BSI Standards Limited 2014ISBN 978 0 580 83807 1

Amendments/corrigenda issued since publication

30 September 2014 Implementation of CEN amendment A1:2014

EUROPÄISCHE NORM

English Version

Gas infrastructure - Welding steel pipework - Functional

requirements

Infrastructures gazières - Soudage des tuyauteries en acier

- Prescriptions fonctionnelles Gasinfrastruktur - Schweißen an Rohrleitungen aus Stahl - Funktionale Anforderungen

This European Standard was approved by CEN on 14 March 2013 and includes Amendment 1 approved by CEN on 3 February 2014 CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member

This European Standard exists in three official versions (English, French, German) A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,

Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom

EUROPEAN COMMITTEE FOR STANDARDIZATION

C O M IT É E U R OP É E N D E N O RM A LIS A T IO N EURO PÄ ISC HES KOM ITE E FÜR NORM UNG

© 2014 CEN All rights of exploitation in any form and by any means reserved

worldwide for CEN national Members Ref No EN 12732:2013+A1:2014 E

Contents

Foreword 6

1 Scope 7

2 Normative references 8

3 Terms and definitions 11

4 Quality system 13

4.1 General 13

4.2 Welding contractors 14

4.3 Welders 15

4.4 Welding supervisory and coordination personnel 15

4.5 Testing companies and personnel 15

4.5.1 General 15

4.5.2 Non-destructive testing (NDT) 15

4.5.3 Destructive testing (DT) 15

5 Welding consumables 15

6 Production welding 16

6.1 General requirements 16

6.1.1 General 16

6.1.2 Working area 16

6.1.3 Layout of weld joints 17

6.1.4 Types of weld joints 17

6.1.5 Joint edge preparation 17

6.1.6 Weld fit-up 17

6.1.7 Different wall thickness 17

6.1.8 Pipe branches and nozzles 17

6.1.9 Laminations 17

6.1.10 Butt welds cross joints 17

6.2 Joint preparation 17

6.2.1 Pipe end preparation 17

6.2.2 Alignment of the joints 17

6.3 Preheating 18

6.4 Tacking 18

6.5 Welding 18

6.6 Actions after welding 18

6.7 Repair of weld defects 19

7 Special procedures 19

7.1 General 19

7.2 Attachment of structural parts 19

7.3 Attachment of cathodic protection connections 19

7.4 Hot-tapping and other welding work on in-service pipelines 20

8 Inspection of the weld joint 20

8.1 General 20

8.2 Scope of inspection 20

8.3 Non-destructive testing and assessment levels 22

8.4 Time of inspection 23

8.5 Acceptance criteria 23

8.6 Recording of test results 24

Contents

Foreword 6

1 Scope 7

2 Normative references 8

3 Terms and definitions 11

4 Quality system 13

4.1 General 13

4.2 Welding contractors 14

4.3 Welders 15

4.4 Welding supervisory and coordination personnel 15

4.5 Testing companies and personnel 15

4.5.1 General 15

4.5.2 Non-destructive testing (NDT) 15

4.5.3 Destructive testing (DT) 15

5 Welding consumables 15

6 Production welding 16

6.1 General requirements 16

6.1.1 General 16

6.1.2 Working area 16

6.1.3 Layout of weld joints 17

6.1.4 Types of weld joints 17

6.1.5 Joint edge preparation 17

6.1.6 Weld fit-up 17

6.1.7 Different wall thickness 17

6.1.8 Pipe branches and nozzles 17

6.1.9 Laminations 17

6.1.10 Butt welds cross joints 17

6.2 Joint preparation 17

6.2.1 Pipe end preparation 17

6.2.2 Alignment of the joints 17

6.3 Preheating 18

6.4 Tacking 18

6.5 Welding 18

6.6 Actions after welding 18

6.7 Repair of weld defects 19

7 Special procedures 19

7.1 General 19

7.2 Attachment of structural parts 19

7.3 Attachment of cathodic protection connections 19

7.4 Hot-tapping and other welding work on in-service pipelines 20

8 Inspection of the weld joint 20

8.1 General 20

8.2 Scope of inspection 20

8.3 Non-destructive testing and assessment levels 22

8.4 Time of inspection 23

8.5 Acceptance criteria 23

8.6 Recording of test results 24

9 Documentation 24

9.1 General 24

9.2 Archiving requirements 24

10 Specific requirements for gas infrastructure with a MOP up to and including 16 bar 24

10.1 General 24

10.2 Welders 24

10.3 Welding supervisory personnel 25

10.4 Production welding 25

10.4.1 General 25

10.4.2 Joint preparation 25

10.4.3 Welding 25

10.5 Requirements for records and documentation 25

11 Specific requirements for gas infrastructure with a MOP greater than 16 bar 26

11.1 General 26

11.2 Welders 26

11.3 Welding supervisory personnel 26

11.4 Qualification of welding procedures 26

11.4.1 General 26

11.4.2 Filler material requirements for welding procedure qualification 26

11.4.3 Impact testing 27

11.4.4 Transverse tensile test 27

11.4.5 All-weld-metal tensile test 28

11.5 Production welding 28

11.5.1 General 28

11.5.2 Joint preparation 28

11.5.3 Welding 28

11.5.4 Repairs of weld defects 29

11.5.5 Welding consumables 29

11.6 Destructive testing of production welds 29

11.7 Acceptance requirements 29

11.8 Requirements for records and documentation 30

12 Specific requirements for metering, regulating and compressor stations 31

12.1 General 31

12.2 Specific requirements 31

Annex A (informative) Qualification procedure for pipeline welders (Girth welds and branch connections) 32

A.1 General 32

A.2 Approval test 32

A.2.1 Execution of the approval test 32

A.2.2 Range of test pieces 32

A.2.3 Supervision of execution of approval test 33

A.3 Inspection 33

A.3.1 General 33

A.3.2 Testing girth welds 34

A.3.3 Testing weldolets 34

A.4 Approval range 34

A.4.1 General 34

A.4.2 Dimension ranges 34

A.4.3 Techniques 34

A.5 Certificate 35

A.5.1 General 35

A.5.2 Duration of validity 35

Annex B (informative) Testing of lamination defects 36

Annex C (informative) Time-of-flight diffraction technique (TOFD) 37

C.1 General 37

C.2 Additional and substitutional requirements to EN ISO 10863:2011 37

C.2.1 Addition to the whole document EN ISO 10863:2011 37

C.2.2 Addition to EN ISO 10863:2011, Clause 3 "Terms and definitions" 37

C.2.3 Addition to EN ISO 10863:2011, Clause 5, "Examination Levels" 39

C.2.4 Addition to EN ISO 10863:2011, 7.2.2, "Ultrasonic probes" 39

C.2.5 Substitution of EN ISO 10863:2011, Clause 11, 3 rd paragraph "Weld testing" 39

C.2.6 Substitution of EN ISO 10863:2011, 12.5.2 "Sizing" 40

Annex D (informative) Critical aspects for hot-tap welding or welding on in-service pipelines 45

D.1 General 45

D.2 Recommendations 45

D.2.1 Equipment 45

D.2.2 Supervision 45

D.2.3 Safety precautions 45

D.2.4 Identification 45

D.2.5 Filler materials 45

D.3 Weld preparation 46

D.4 Welding procedure specification (WPS) 46

D.4.1 Description of the WPS 46

D.4.2 Qualification of the WPS 46

D.4.3 Approval of the WPS 46

D.5 Qualification of the welder 46

D.6 Precautions 46

D.7 Execution 47

D.8 Repairs 47

D.9 WPS qualification record 47

Annex E (informative) Visual examination of joints 49

E.1 General 49

E.2 Recommendations 49

Annex F (informative) Manual ultrasonic testing of weld joints for wall thickness between approximately 6 mm and 8 mm 50

F.1 General 50

A.4.3 Techniques 34

A.5 Certificate 35

A.5.1 General 35

A.5.2 Duration of validity 35

Annex B (informative) Testing of lamination defects 36

Annex C (informative) Time-of-flight diffraction technique (TOFD) 37

C.1 General 37

C.2 Additional and substitutional requirements to EN ISO 10863:2011 37

C.2.1 Addition to the whole document EN ISO 10863:2011 37

C.2.2 Addition to EN ISO 10863:2011, Clause 3 "Terms and definitions" 37

C.2.3 Addition to EN ISO 10863:2011, Clause 5, "Examination Levels" 39

C.2.4 Addition to EN ISO 10863:2011, 7.2.2, "Ultrasonic probes" 39

C.2.5 Substitution of EN ISO 10863:2011, Clause 11, 3 rd paragraph "Weld testing" 39

C.2.6 Substitution of EN ISO 10863:2011, 12.5.2 "Sizing" 40

Annex D (informative) Critical aspects for hot-tap welding or welding on in-service pipelines 45

D.1 General 45

D.2 Recommendations 45

D.2.1 Equipment 45

D.2.2 Supervision 45

D.2.3 Safety precautions 45

D.2.4 Identification 45

D.2.5 Filler materials 45

D.3 Weld preparation 46

D.4 Welding procedure specification (WPS) 46

D.4.1 Description of the WPS 46

D.4.2 Qualification of the WPS 46

D.4.3 Approval of the WPS 46

D.5 Qualification of the welder 46

D.6 Precautions 46

D.7 Execution 47

D.8 Repairs 47

D.9 WPS qualification record 47

Annex E (informative) Visual examination of joints 49

E.1 General 49

E.2 Recommendations 49

Annex F (informative) Manual ultrasonic testing of weld joints for wall thickness between approximately 6 mm and 8 mm 50

F.1 General 50

F.2 Setting 50

F.2.1 Setting of range 50

F.2.2 Sensitivity adjustment when using the Distance Gain Size method 50

Annex G (normative) Acceptance criteria - Recommendations for on-site production welds 54

G.1 General 54

G.2 Acceptance criteria according to EN ISO 5817 54

G.3 Summary of requirements for defect acceptance levels and defect limits 57

G.3.1 General 57

G.3.2 Requirements 58

G.4 Method and acceptance criteria for ultrasonic inspection assessment 65

G.4.1 Distance Gain Size method 65

G.4.2 Comparative Element method 65

G.4.3 General 65

G.4.4 Assessment of indications using automatic pulse-echo technique 67

Annex H (informative) Brazing and aluminothermic welding of leads for cathodic protection systems 68

H.1 Joining techniques 68

H.2 Procedure qualification 68

H.3 Operation qualification 70

H.4 Production joints 70

Annex I (informative) Significant technical changes between this European Standard and the previous edition 71

Bibliography 72

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights This document supersedes !EN 12732:2013"

This document includes Amendment 1 approved by CEN on 2014-02-03

The start and finish of text introduced or altered by amendment is indicated in the text by tags !"

This European Standard has been prepared under mandate M/017 given to CEN by the Commission of the European Communities and the European Free Trade Association

Annex I provides details of significant technical changes between this European Standard and the previous edition

There is a complete suite of functional standards prepared by CEN/TC 234 ”Gas infrastructure“ to cover all parts from the input of gas to the transmission system up to the inlet connection of the gas appliances, whether for domestic, commercial or industrial purposes

In preparing this standard a basic understanding of gas infrastructure by the user has been assumed

Gas infrastructure is complex and the importance on safety of its construction and use has led to the development of very detailed codes of practice and operating manuals in the member countries These detailed statements embrace recognised standards of gas engineering and the specific requirements imposed

by the legal structures of the member countries

CEN/TC 234 will continue its work updating this standard to the latest developments at regular intervals According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom

Foreword

This document (EN 12732:2013+A1:2014) has been prepared by Technical Committee CEN/TC 234 “Gas

infrastructure”, the secretariat of which is held by DIN

This European Standard shall be given the status of a national standard, either by publication of an identical

text or by endorsement, at the latest by October 2014, and conflicting national standards shall be withdrawn at

the latest by October 2014

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent

rights CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights

This document supersedes !EN 12732:2013"

This document includes Amendment 1 approved by CEN on 2014-02-03

The start and finish of text introduced or altered by amendment is indicated in the text by tags !"

This European Standard has been prepared under mandate M/017 given to CEN by the Commission of the

European Communities and the European Free Trade Association

Annex I provides details of significant technical changes between this European Standard and the previous

edition

There is a complete suite of functional standards prepared by CEN/TC 234 ”Gas infrastructure“ to cover all

parts from the input of gas to the transmission system up to the inlet connection of the gas appliances,

whether for domestic, commercial or industrial purposes

In preparing this standard a basic understanding of gas infrastructure by the user has been assumed

Gas infrastructure is complex and the importance on safety of its construction and use has led to the

development of very detailed codes of practice and operating manuals in the member countries These

detailed statements embrace recognised standards of gas engineering and the specific requirements imposed

by the legal structures of the member countries

CEN/TC 234 will continue its work updating this standard to the latest developments at regular intervals

According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following

countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech

Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece,

Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,

Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom

1 Scope

This European Standard contains requirements for the production and testing of weld joints for the installation and modification of onshore steel pipelines and pipework used in gas infrastructure, including in-service pipelines, for all pressure ranges for the carriage of processed, non-toxic and non-corrosive natural gas according to EN ISO 13686 and for the carriage of non-conventional gases such as injected biomethane, where

— the pipeline elements are made of unalloyed or low-alloyed carbon steel;

— the pipeline is not located within commercial or industrial premises as integral part of the industrial process on those premises except for any pipelines and facilities delivering gas to such premises;

— the pipework is not located within household installations according to EN 1775;

— the design temperature of the system is between -40 °C up to and including 120 °C

The onshore steel pipelines and pipework used in gas infrastructure include in-service pipelines, for all pressure ranges for the carriage of processed, non-toxic and non-corrosive natural gas according to

EN ISO 13686 and for the carriage of non-conventional gases complying with EN ISO 13686, and for which a detailed technical evaluation of the functional requirements (such as injected biomethane) is performed ensuring there are no other constituents or properties of the gases that can affect the integrity of the pipeline This standard is not applicable to welds produced prior to the publication of this European Standard

Table 1 assigns the application areas to quality requirement categories as a function of the working pressure and pipe materials used

Table 1 — Allocation to quality requirement categories Quality requirement

category Area of activity applies to

B Pressure range and base material ≤ 5 bar

Group 1.1, 1.2 and 1.4 according to CEN ISO/TR 15608

Rt 0,5 ≤ 360 N/mm2Examples of use: Mains and service pipes in gas distribution systems, pipework in stations

C Pressure range and base material > 5 bar ≤ 16 bar

Group 1.1, 1.2 and 1.4 according to CEN ISO/TR 15608

Rt 0,5 ≤ 360 N/mm2Examples of use: Pipelines including pipework in stations and gas distribution systems

D Pressure range or base material > 16 bar a

Group 1, 2 and 3 according to CEN ISO/TR 15608

Quality requirement

category Area of activity applies to

Examples of use: Pipelines including pipework in stations and gas transmission systems

Key

Rt 0,5 is the specified minimum yield strength according to EN ISO 3183

NOTE 1 "Category A" for pipework up to and including 100 mbar, as mentioned in the previous version

EN 12732:2000, has been incorporated in the pressure range of "Category B" and has been deleted from this table

NOTE 2 Gas infrastructure with a MOP up to and including 16 bar is generally dedicated to gas distribution

a Pipelines having hoop stresses at design pressure up to 30 % of specified minimum

yield strength (Rt 0,5) and operated at a pressure up to 24 bar may be allocated to quality requirement Category C by the pipeline operator

Additional requirements may be specified when, for example:

— the strain on pipelines and systems,

— the materials,

— the line routing,

— the design or the welding technique

are considered critical

This European Standard specifies common basic principles for gas infrastructure Users of this European Standard should be aware that there can exist more detailed national standards and/or codes of practice in the CEN member countries

This European Standard is intended to be applied in association with these national standards and/or codes of practice setting out the above-mentioned basic principles

In the event of conflicts in terms of more restrictive requirements in national legislation/regulation with the requirements of this standard, the national legislation/regulation takes precedence as illustrated in CEN/TR 13737 (all parts)

NOTE CEN/TR 13737 (all parts) contains:

— clarification of relevant legislation/regulations applicable in a country;

— if appropriate, more restrictive national requirements;

— national contact point for the latest information

2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application For dated references, only the edition cited applies For undated references, the latest edition of the referenced document (including any amendments) applies

Quality requirement

category Area of activity applies to

Examples of use: Pipelines including pipework in stations and

gas transmission systems

Key

Rt 0,5 is the specified minimum yield strength according to EN ISO 3183

NOTE 1 "Category A" for pipework up to and including 100 mbar, as mentioned in the previous version

EN 12732:2000, has been incorporated in the pressure range of "Category B" and has been deleted from this

table

NOTE 2 Gas infrastructure with a MOP up to and including 16 bar is generally dedicated to gas distribution

a Pipelines having hoop stresses at design pressure up to 30 % of specified minimum

yield strength (Rt 0,5) and operated at a pressure up to 24 bar may be allocated to quality

requirement Category C by the pipeline operator

Additional requirements may be specified when, for example:

— the strain on pipelines and systems,

— the materials,

— the line routing,

— the design or the welding technique

are considered critical

This European Standard specifies common basic principles for gas infrastructure Users of this European

Standard should be aware that there can exist more detailed national standards and/or codes of practice in

the CEN member countries

This European Standard is intended to be applied in association with these national standards and/or codes of

practice setting out the above-mentioned basic principles

In the event of conflicts in terms of more restrictive requirements in national legislation/regulation with the

requirements of this standard, the national legislation/regulation takes precedence as illustrated in

CEN/TR 13737 (all parts)

NOTE CEN/TR 13737 (all parts) contains:

— clarification of relevant legislation/regulations applicable in a country;

— if appropriate, more restrictive national requirements;

— national contact point for the latest information

2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are

indispensable for its application For dated references, only the edition cited applies For undated references,

the latest edition of the referenced document (including any amendments) applies

EN 287-1, Qualification test of welders — Fusion welding — Part 1: Steels

EN 1418:1997, Welding personnel — Approval testing of welding operators for fusion welding and resistance weld setters for fully mechanized and automatic welding of metallic materials

EN 1708-1, Welding - Basic welded joint details in steel - Part 1: Pressurized components

EN 10204, Metallic products - Types of inspection documents

EN ISO 636, Welding consumables — Rods, wires and deposits for tungsten inert gas welding of non-alloy and fine-grain steels — Classification (ISO 636)

EN ISO 2560, Welding consumables — Covered electrodes for manual metal arc welding of non-alloy and fine grain steels — Classification (ISO 2560)

EN ISO 3183, Petroleum and natural gas industries — Steel pipe for pipeline transportation systems (ISO 3183)

EN ISO 3452 (all parts), Non-destructive testing — Penetrant testing (ISO 3452)

EN ISO 3834-1, Quality requirements for fusion welding of metallic materials — Part 1: Criteria for the selection of the appropriate level of quality requirements (ISO 3834-1)

EN ISO 3834-2, Quality requirements for fusion welding of metallic materials — Part 2: Comprehensive quality requirements (ISO 3834-2)

EN ISO 3834-3, Quality requirements for fusion welding of metallic materials — Part 3: Standard quality requirements (ISO 3834-3)

EN ISO 3834-4, Quality requirements for fusion welding of metallic materials — Part 4: Elementary quality requirements (ISO 3834-4)

EN ISO 5817, Welding — Fusion-welded joints in steel, nickel, titanium and their alloys (beam welding excluded) — Quality levels for imperfections (ISO 5817)

EN ISO 6520-1, Welding and allied processes — Classification of geometric imperfections in metallic materials — Part 1: Fusion welding (ISO 6520-1)

EN ISO 6892-1, Metallic materials — Tensile testing — Part 1: Method of test at room temperature (ISO 6892-1)

EN ISO 9692-1, Welding and allied processes — Recommendations for joint preparation — Part 1: Manual metal-arc welding, gas-shielded metal-arc welding, gas welding, TIG welding and beam welding of steels (ISO 9692-1)

EN ISO 9712, Non-destructive testing — Qualification and certification of NDT personnel (ISO 9712)

EN ISO 10863:2011, Non-destructive testing of welds - Ultrasonic testing - Use of time-of-flight diffraction technique (TOFD) (ISO 10863:2011)

EN ISO 14171, Welding consumables — Solid wire electrodes, tubular cored electrodes and electrode/flux combinations for submerged arc welding of non alloy and fine grain steels — Classification (ISO 14171)

EN ISO 14174, Welding consumables — Fluxes for submerged arc welding and electroslag welding — Classification (ISO 14174)

EN ISO 14175, Welding consumables — Gases and gas mixtures for fusion welding and allied processes (ISO 14175)

EN ISO 14341, Welding consumables — Wire electrodes and weld deposits for gas shielded metal arc welding of non alloy and fine grain steels - Classification (ISO 14341)

EN ISO 14731, Welding coordination — Tasks and responsibilities (ISO 14731)

EN ISO 15607:2003, Specification and qualification of welding procedures for metallic materials - General rules (ISO 15607:2003)

CEN ISO/TR 15608, Welding — Guidelines for a metallic materials grouping system (ISO/TR 15608)

EN ISO 15609-1, Specification and qualification of welding procedures for metallic materials — Welding procedure specification — Part 1: Arc welding (ISO 15609-1)

EN ISO 15609-2, Specification and qualification of welding procedures for metallic materials — Welding procedure specification — Part 2: Gas welding (ISO 15609-2)

EN ISO 15610, Specification and qualification of welding procedures for metallic materials — Qualification based on tested welding consumables (ISO 15610)

EN ISO 15611, Specification and qualification of welding procedures for metallic materials — Qualification based on previous welding experience (ISO 15611)

EN ISO 15612, Specification and qualification of welding procedures for metallic materials — Qualification by adoption of a standard welding procedure (ISO 15612)

EN ISO 15613, Specification and qualification of welding procedures for metallic materials — Qualification based on pre-production welding test (ISO 15613)

EN 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 15614- 1)

EN ISO/IEC 17020, Conformity assessment — Requirements for the operation of various types of bodies performing inspection (ISO/IEC 17020)

EN ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories (ISO/IEC 17025)

EN ISO 17636-1, Non-destructive testing of welds — Radiographic testing — Part 1: X- and gamma-ray techniques with film (ISO 17636-1)

EN ISO 17636-2, Non-destructive testing of welds — Radiographic testing — Part 2: X- and gamma-ray techniques with digital detectors (ISO 17636-2)

EN ISO 17632, Welding consumables — Tubular cored electrodes for gas shielded and non-gas shielded metal arc welding of non-alloy and fine grain steels — Classification (ISO 17632)

EN ISO 17637, Non-destructive testing of welds — Visual testing of fusion-welded joints (ISO 17637)

EN ISO 17638, Non-destructive testing of welds — Magnetic particle testing (ISO 17638)

EN ISO 17640, Non-destructive testing of welds — Ultrasonic testing — Techniques, testing levels, and assessment (ISO 17640)

EN ISO 14175, Welding consumables — Gases and gas mixtures for fusion welding and allied processes

(ISO 14175)

EN ISO 14341, Welding consumables — Wire electrodes and weld deposits for gas shielded metal arc

welding of non alloy and fine grain steels - Classification (ISO 14341)

EN ISO 14731, Welding coordination — Tasks and responsibilities (ISO 14731)

EN ISO 15607:2003, Specification and qualification of welding procedures for metallic materials - General

rules (ISO 15607:2003)

CEN ISO/TR 15608, Welding — Guidelines for a metallic materials grouping system (ISO/TR 15608)

EN ISO 15609-1, Specification and qualification of welding procedures for metallic materials — Welding

procedure specification — Part 1: Arc welding (ISO 15609-1)

EN ISO 15609-2, Specification and qualification of welding procedures for metallic materials — Welding

procedure specification — Part 2: Gas welding (ISO 15609-2)

EN ISO 15610, Specification and qualification of welding procedures for metallic materials — Qualification

based on tested welding consumables (ISO 15610)

EN ISO 15611, Specification and qualification of welding procedures for metallic materials — Qualification

based on previous welding experience (ISO 15611)

EN ISO 15612, Specification and qualification of welding procedures for metallic materials — Qualification by

adoption of a standard welding procedure (ISO 15612)

EN ISO 15613, Specification and qualification of welding procedures for metallic materials — Qualification

based on pre-production welding test (ISO 15613)

EN 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

15614-1)

EN ISO/IEC 17020, Conformity assessment — Requirements for the operation of various types of bodies

performing inspection (ISO/IEC 17020)

EN ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories (ISO/IEC

17025)

EN ISO 17636-1, Non-destructive testing of welds — Radiographic testing — Part 1: X- and gamma-ray

techniques with film (ISO 17636-1)

EN ISO 17636-2, Non-destructive testing of welds — Radiographic testing — Part 2: X- and gamma-ray

techniques with digital detectors (ISO 17636-2)

EN ISO 17632, Welding consumables — Tubular cored electrodes for gas shielded and non-gas shielded

metal arc welding of non-alloy and fine grain steels — Classification (ISO 17632)

EN ISO 17637, Non-destructive testing of welds — Visual testing of fusion-welded joints (ISO 17637)

EN ISO 17638, Non-destructive testing of welds — Magnetic particle testing (ISO 17638)

EN ISO 17640, Non-destructive testing of welds — Ultrasonic testing — Techniques, testing levels, and

assessment (ISO 17640)

EN ISO 18275, Welding consumables — Covered electrodes for manual metal arc welding of high-strength steels — Classification (ISO 18275)

IIW-IAB -252-07, Personnel with responsibility for welding coordination

3 Terms and definitions

For the purposes of this document, the following terms and definitions apply Symbols used in formulae are defined where they occur

3.1 design temperature

DT

temperature on which the design calculations are based

3.2 gas

gaseous fuel which is in a gaseous state at a temperature of 15 °C under atmospheric pressure (1,013 25 bar absolute)

3.3 gas infrastructure

all pipelines, stations and installations from the input of gas to the transmission system up to the inlet connection of the gas appliances, whether for domestic, commercial or industrial purposes

3.4 gas distribution system

pipeline system including piping above and below ground and all other equipment necessary to deliver the gas

to the consumer

3.5 gas transmission

activity intended to convey gas from one place to another through pipelines in order to deliver gas to distribution systems or to industrial consumers

3.6 installation

equipment and facilities for the extraction, production, chemical treatment, measurement, control, storage or off-take of the transported gas

3.7 maximum operating pressure MOP

maximum pressure at which a system can be operated continuously under normal conditions

Note 1 to entry: normal conditions are: no fault in any device or stream

3.8 national requirements

requirements following from national legislation or more detailed or stringent national standards

3.9 onshore pipeline

buried and/or above ground pipeline including those sections laid in or across inland lakes or water courses

elements from which a pipeline is constructed The following are distinct pipeline elements:

— pipe including cold-formed bends;

— fittings

EXAMPLE 1 Reducers, tees, factory-made elbows and bends, flanges, caps, welding stubs, mechanical joints

— fabrications, manufactured from elements referred above;

EXAMPLE 2 Manifolds, slug catchers, pig launching/receiving stations, metering and control runs

pressure to which a part of the gas infrastructure is subjected to, to ensure safe operation

Note 1 to entry: The test pressure can be different for the different parts of the infrastructure to be tested

3.10

pipeline

system of pipework with all associated equipment and stations up to the point of delivery This pipework is

mainly below ground but also includes above ground parts

3.11

pipeline components

elements from which a pipeline is constructed The following are distinct pipeline elements:

— pipe including cold-formed bends;

— fittings

EXAMPLE 1 Reducers, tees, factory-made elbows and bends, flanges, caps, welding stubs, mechanical joints

— fabrications, manufactured from elements referred above;

EXAMPLE 2 Manifolds, slug catchers, pig launching/receiving stations, metering and control runs

private or public organisation authorised to design, construct, and/or operate and maintain the gas

infrastructure, i.e gas transmission operators (TSO) and gas distribution operators (DSO)

pressure to which a part of the gas infrastructure is subjected to, to ensure safe operation

Note 1 to entry: The test pressure can be different for the different parts of the infrastructure to be tested

3.17

weld repair

process of repairing a defect that is discovered after the weld has been completed, by additional welding and

submitted for inspection

Note 1 to entry: The repair can involve complete removal of a cylinder of pipe or removal of a localised area by

grinding or other means followed by additional welding

3.18 welder

person who holds and manipulates the electrode holder, welding torch or blow pipe by hand

3.19 welding procedure specification (WPS)

a document that has been qualified by one of the methods described in EN ISO 15607:2003, Clause 6, and provides the required variables of the welding procedure to ensure repeatability during production welding

3.20 temper bead method

a weld sequence whereby the heat-affected zone of the base material is softened as much as possible

3.21 Hydrogen Dissolved in Metal HDM

the amount of diffusible hydrogen in 100 mg of weld metal

4 Quality system 4.1 General

If required by the pipeline operator, a quality system shall be applied to pipeline welding A set of recommended quality requirements according to EN ISO 3834 is provided in Table 2, which specifies the requirements of EN ISO 3834 for the different categories as defined in Table 1

Table 2 — Recommended quality requirements

category in accordance with Table 1

Quality system according to:

Welding coordination personnel:

— Personnel according to EN ISO 14731:

Welding procedure specification (WPS):

Approval of welding procedures according to one of the following

standards:

If required by the pipeline operator, contractors shall demonstrate their ability to perform the work Reference

can be made to EN ISO 3834

Table 2 — Recommended quality requirements

category in accordance with Table 1

Quality system according to:

Welding coordination personnel:

— Personnel according to EN ISO 14731:

Welding procedure specification (WPS):

Approval of welding procedures according to one of the following

standards:

If required by the pipeline operator, contractors shall demonstrate their ability to perform the work Reference

can be made to EN ISO 3834

4.3 Welders

All welders shall be qualified for the work they are required to undertake

The qualification should be carried out in accordance with Clauses 10, 11 and 12

4.4 Welding supervisory and coordination personnel

If a quality system is required by the pipeline operator, the supervisory and the coordination personnel should

be qualified according to EN ISO 14731 as indicated in Table 2

Welding tasks and responsibilities for welding shall be clearly assigned to personnel with the appropriate experience and technical knowledge

4.5 Testing companies and personnel

4.5.1 General

Destructive testing and non-destructive testing personnel shall be employed either by the pipeline contractor

or by the pipeline operator or by an independent testing company All companies providing such personnel

!shall at least" be certified in accordance with the paragraphs below

Welding consumables shall be in accordance with:

— EN ISO 2560 and EN ISO 18275 for shielded metal arc welding (process no 111);

— EN ISO 14341 and EN ISO 636 for gas metal arc welding (process nos 135, 141);

— EN ISO 17632 for flux-cored arc welding (process nos 114, 136);

— EN ISO 14175 for shielding gases;

— EN ISO 14171 for submerged arc welding (process no 12);

— EN ISO 14174 for fluxes for submerged arc welding (process no 12)

The numbering of the processes given in brackets is in accordance with EN ISO 4063

All filler materials shall be certified as conforming to the above listed European Standards

Batch testing of the filler materials can be required by the pipeline operator In this case the certificates shall

be in accordance with EN 10204, type 3.1 The chemical composition of the deposited weld metal shall be compatible with the parent metal, taking into account any specific property requirements

Unless otherwise agreed, matching weld metal for girth welds shall be required For the selection of consumables, the use of Table 3 is recommended

After filler material has been removed from its original package, it shall be protected or stored in accordance with the manufacturer's requirements, so that its characteristics or welding properties are not affected

Table 3 — Matching filler material requirements Steel specification to EN ISO 3183 a Filler material requirements

Rt 0,5 Specified minimum yield strength measured in N/mm2

Rm Tensile strength according to EN ISO 3183 measured in N/mm2

Rp 0,2 0,2 % proof strength according to EN ISO 6892-1 measured in N/mm2

KV Impact test value (Charpy-V method) obtained for full size specimen (average/individual)

Unless otherwise agreed, matching weld metal for girth welds shall be required For the selection of

consumables, the use of Table 3 is recommended

After filler material has been removed from its original package, it shall be protected or stored in accordance

with the manufacturer's requirements, so that its characteristics or welding properties are not affected

Table 3 — Matching filler material requirements Steel specification to EN ISO 3183 a Filler material requirements

Rt 0,5 Specified minimum yield strength measured in N/mm2

Rm Tensile strength according to EN ISO 3183 measured in N/mm2

Rp 0,2 0,2 % proof strength according to EN ISO 6892-1 measured in N/mm2

KV Impact test value (Charpy-V method) obtained for full size specimen (average/individual)

The working space shall enable adequate access to the working area in order to provide a safe environment

and to allow satisfactory production and testing of a weld joint

6.1.3 Layout of weld joints

Weld joints, in particular tie-ins, shall be arranged and designed in a way suited to the planned welding and testing technique The placement of tie-in welds is particularly important

6.1.4 Types of weld joints

Unless otherwise agreed, pipes and pipeline fittings shall be connected using butt-welded joints

6.1.5 Joint edge preparation

Joint edge preparations shall comply with the appropriate European Standards and the approved welding procedure, such as EN 1708-1 and EN ISO 9692-1 The choice of joint configuration shall take into account the welding technique, the welding position and the accessibility of the joint

6.1.6 Weld fit-up

Weld fit-up shall be sufficient to ensure a good penetration of the joint

6.1.7 Different wall thickness

When pipes and/or fittings of different wall thicknesses have to be joined together, special precautions shall be taken to avoid stress concentration and weld defects

When butt welding pipework of different wall thicknesses has to be performed, 6.2.2 and/or EN 1708-1 shall apply

6.1.8 Pipe branches and nozzles

Forged fittings are preferred Weld-on branches and nozzles are allowed

6.1.9 Laminations

Examination of the pipe ends for the presence of laminations should be performed after a significant length of pipe has been removed, except for branches, nozzles and structural parts Additional precautions can be required where welding is performed in the area of laminations

6.1.10 Butt welds cross joints

Unless otherwise agreed, butt welded cross joints shall be avoided

6.2 Joint preparation

6.2.1 Pipe end preparation

To ensure that the required weld quality is achieved; all necessary details concerning the joint preparation shall be laid down in the welding procedure specification

6.2.2 Alignment of the joints

Alignment clamps shall be used where possible; the details and how they are to be used shall be included in the welding procedure specification

Root misalignment is acceptable as far as it is not affecting the integrity of the joint For recommendations see Table G.1

Misalignment of pipes and pipelines made of steel grades with a minimum specified yield strength Rt 0,5 less than or equal to 360 N/mm2 which is outside the tolerance range of the tables given in Annex G can be compensated for by deformation, if agreed by the pipeline operator, by the use of special equipment or by transition pieces The heat-treatment condition of the material shall be taken into account

NOTE In some cases, the strength of thermo-mechanically treated as well as quenched and tempered steels is permanently reduced by heating to temperatures above 580 °C

Root misalignment of pipes and pipelines of different wall thicknesses and made of steel grades with a

specified minimum yield strength Rt 0,5 greater than 360 N/mm2, which is outside the tolerance range of the tables given in Annex G, shall be compensated for by using transition pieces

During correction of excessive root misalignment, measures shall be taken to avoid defects Examples of permissible weld configurations are given in EN 1708-1

6.5 Welding

Each weld on a pipe with a diameter larger than or equal to DN 400 shall be welded simultaneously by at least two welders, (one on each side of the girth weld)

Precautions shall be taken to:

— minimise hydrogen pick-up in the work, in particular for steels which are sensitive to cold cracking;

— avoid condensation;

— avoid air movements in the pipe;

— avoid uncontrolled electrical current;

— minimise magnetic effects;

— avoid cold cracking;

— avoid arc strikes

6.6 Actions after welding

After the weld is completed, weld spatter shall be removed The weld surface shall be cleaned of slag The cooling process shall not be accelerated beyond the rate specified in the welding procedure specification Where air temperatures are below 5 °C and/or poor climatic conditions like wind or rain prevail, or if the pipeline operator requires it, the weld joint shall be protected against excessive rapid cooling

Misalignment of pipes and pipelines made of steel grades with a minimum specified yield strength Rt 0,5 less

than or equal to 360 N/mm2 which is outside the tolerance range of the tables given in Annex G can be

compensated for by deformation, if agreed by the pipeline operator, by the use of special equipment or by

transition pieces The heat-treatment condition of the material shall be taken into account

NOTE In some cases, the strength of thermo-mechanically treated as well as quenched and tempered steels is

permanently reduced by heating to temperatures above 580 °C

Root misalignment of pipes and pipelines of different wall thicknesses and made of steel grades with a

specified minimum yield strength Rt 0,5 greater than 360 N/mm2, which is outside the tolerance range of the

tables given in Annex G, shall be compensated for by using transition pieces

During correction of excessive root misalignment, measures shall be taken to avoid defects Examples of

permissible weld configurations are given in EN 1708-1

6.3 Preheating

Preheating shall be applied in accordance with the welding procedure specification

6.4 Tacking

Whenever tack welds are used, they shall be made using the welding procedure designed for the root pass

and they shall be performed by a qualified welder They shall be distributed equally around the circumference

The tacks shall be free from cracks Cracked tacks shall not be welded over, and shall be ground out and

re-welded When blocks are used to line up, the material shall be of an appropriate steel grade

6.5 Welding

Each weld on a pipe with a diameter larger than or equal to DN 400 shall be welded simultaneously by at least

two welders, (one on each side of the girth weld)

Precautions shall be taken to:

— minimise hydrogen pick-up in the work, in particular for steels which are sensitive to cold cracking;

— avoid condensation;

— avoid air movements in the pipe;

— avoid uncontrolled electrical current;

— minimise magnetic effects;

— avoid cold cracking;

— avoid arc strikes

6.6 Actions after welding

After the weld is completed, weld spatter shall be removed The weld surface shall be cleaned of slag The

cooling process shall not be accelerated beyond the rate specified in the welding procedure specification

Where air temperatures are below 5 °C and/or poor climatic conditions like wind or rain prevail, or if the

pipeline operator requires it, the weld joint shall be protected against excessive rapid cooling

Stress-relief heat treatment can be necessary

6.7 Repair of weld defects

Weld joints which do not meet the specified requirements shall be repaired or cut out On each weld joint which requires repair, the faulty area shall be clearly marked The marking shall not be removed until the defect has been repaired and the repair work has been inspected If a defect, which requires repair, exceeds more than 20 % of the total weld length, or if several defective weld sections amount to 20 % of the total weld length, the weld joint in question shall be cut out and re-welded unless otherwise agreed by the pipeline operator

Weld joints with cracks shall be completely cut out However, in special cases, and where approved by the pipeline operator, cracks may be repaired, provided the cause of the crack has been established beyond doubt and provided it is confirmed that the fault has been correctly identified

Repairs shall be retested non-destructively using suitable techniques If non-destructive testing of a repair reveals that the repaired area still has unacceptable indications, the weld shall be cut out and re-welded unless otherwise agreed by the pipeline operator

7 Special procedures 7.1 General

Before special procedures, as given below, are carried out, the type and scope of testing of the weld joint shall

be specified The scope of the testing shall be in accordance with 8.2 The testing technique used will depend

on the type and dimension of the weld

7.2 Attachment of structural parts

Structural parts shall be attached using a continuous weld Intermittent welds shall not be used

When welding structural parts onto components made of steel grades with specified minimum yield strength greater than 360 N/mm2, special measures shall be employed which take account of the material characteristics

EXAMPLE Buttering with low-yield/low-hydrogen electrodes

These precautions shall be specified in the welding procedure specification

7.3 Attachment of cathodic protection connections

Electrical bonds to the pipe surface shall be made with a welding or brazing method which does not alter the integrity of the metal It shall be demonstrated by a performance test that the metallurgical structure is not adversely affected

To qualify for making cathodic protection connections, the operator's skill shall be tested under site conditions before work begins

When cable connections are made to the pipeline, the adhesion of the weld shall be verified

Comprehensive information is given in Annex H

7.4 Hot-tapping and other welding work on in-service pipelines

All hot-tap welding procedures shall include the following additional requirements

Hot-tap welding shall only be carried out after sufficient research and development to ensure the safety of the operation and the correct mechanical properties of the weld

Prior to the execution of welding work on in-service pipelines, the pipeline operator shall decide whether the design, the material and the construction condition of the pipeline allow welding under operating pressure Critical aspects for hot-tap welding shall be included in the welding procedure specification and shall be subject to approval by the pipeline operator Detailed information on critical aspects is given in Annex D Welding sleeves and split-tees greater than DN 50 for use on pipelines made of steel grades with specified minimum yield strength greater than 360 N/mm2 shall be of the split full-encirclement type or shall incorporate additional local reinforcement

The longitudinal seam weld of a split attachment shall not be allowed to impinge on the pipe wall of the service pipe

in-Where the attachments are of steel grades with specified minimum yield strength greater than 360 N/mm2 or are designed so that longitudinal contraction stresses can cause deformation, the first circumferential fillet weld shall be completed before the second is started The cooling rate shall not be increased

Where tacks for installation purposes are necessary in the area of the second circumferential weld these shall

be ground out completely

8 Inspection of the weld joint

The pipeline operator shall select which welds are to be tested

Where less than 100 % non-destructive testing is performed and the quality of the weld joint does not meet the requirements, further welds shall be examined to determine the extent of the problem The cause of the fault shall be eliminated Except when otherwise agreed, two further welds shall be inspected for each rejected weld

7.4 Hot-tapping and other welding work on in-service pipelines

All hot-tap welding procedures shall include the following additional requirements

Hot-tap welding shall only be carried out after sufficient research and development to ensure the safety of the

operation and the correct mechanical properties of the weld

Prior to the execution of welding work on in-service pipelines, the pipeline operator shall decide whether the

design, the material and the construction condition of the pipeline allow welding under operating pressure

Critical aspects for hot-tap welding shall be included in the welding procedure specification and shall be

subject to approval by the pipeline operator Detailed information on critical aspects is given in Annex D

Welding sleeves and split-tees greater than DN 50 for use on pipelines made of steel grades with specified

minimum yield strength greater than 360 N/mm2 shall be of the split full-encirclement type or shall incorporate

additional local reinforcement

The longitudinal seam weld of a split attachment shall not be allowed to impinge on the pipe wall of the

in-service pipe

Where the attachments are of steel grades with specified minimum yield strength greater than 360 N/mm2 or

are designed so that longitudinal contraction stresses can cause deformation, the first circumferential fillet

weld shall be completed before the second is started The cooling rate shall not be increased

Where tacks for installation purposes are necessary in the area of the second circumferential weld these shall

be ground out completely

8 Inspection of the weld joint

8.1 General

Weld quality shall be ensured by inspection of the welds using destructive tests and/or non-destructive testing

The results of these tests shall be documented

8.2 Scope of inspection

The inspection shall comprise inspection during welding, final visual inspection, non-destructive testing and

destructive testing

The minimum extent of non-destructive testing in respect of the quality requirement category and the

type/position of the weld joint is given in Table 4

The pipeline operator shall select which welds are to be tested

Where less than 100 % non-destructive testing is performed and the quality of the weld joint does not meet

the requirements, further welds shall be examined to determine the extent of the problem The cause of the

fault shall be eliminated Except when otherwise agreed, two further welds shall be inspected for each

rejected weld

Table 4 — Minimum extent of non-destructive testing

Quality requirement category in accordance with Table 1

Type/position of the weld joint

Visual examination

by welding supervisor

pipelines on bridges, pipeline sections crossing railways, major roads and motorways, navigable waterways or landing strips/runways

pipelines on bridges, pipeline sections crossing railways, major roads and motorways, navigable waterways or landing strips/runways

Weld joints not included in the

If pipelines/units are laid or

pipelines on bridges, pipeline sections crossing railways, major roads and motorways, navigable waterways or landing strips/runways

Key

UT ultrasonic testing TOFD Time-of-flight diffraction technique

a The proportion of techniques shall be agreed

by welding supervisor

b The extent of NDT depends on the representative random sample on the basis of the total number of weld

joints made by a welder during the course of one year

c The pipeline operator shall specify the extent of non-destructive testing taking into account the design

conditions, for example:

— external loads in addition to internal pressure;

— supports;

— expansion due to temperature;

— earthquake risk

d Where welds with incomplete penetration are used, the pipeline operator can require 100 %

e Seams shall be tested 100 % by two different inspection techniques

f For branches and nozzles, consideration should be given by the pipeline operator to these methods

8.3 Non-destructive testing and assessment levels

The method or combination of methods for visual and other non-destructive testing of the welds shall be specified by the pipeline operator Prior to commencement of welding, the non-destructive testing procedures shall be submitted to the pipeline operator for acceptance Inspection test methods may be replaced by other methods, if agreed by the pipeline operator Non-destructive testing procedure shall be approved by a NDT expert Level III according to EN ISO 9712 for the appropriate examination technique

Other forms of non-destructive testing can be required, depending on the material used, the design and/or the welding technique

Visual examination of welds shall be carried out in accordance with EN ISO 17637 Supplementary information is given in Annex E

Radiographic examination shall be carried out in accordance with EN ISO 17636-1 and EN ISO 17636-2 If not otherwise agreed by the pipeline operator, the image quality class given in EN ISO 17636-1 and EN ISO 17636-2 shall be:

— Class A for categories B and C;

— Class B for Category D

Ultrasonic impulse echo examination shall be carried out in accordance with EN ISO 17640 For wall thickness from 6 mm to 8 mm guidance is given in Annex F

Ultrasonic TOFD examination according to EN ISO 10863 may be used for detection and sizing of weld defects and defects adjacent to the weld Supplementary specification on EN ISO 10863 is given in Annex C

In welding process numbers 114, 135 and 136 given in EN ISO 4063, additional ultrasonic testing can be applied

Dye-penetrant examination shall be carried out in accordance with EN ISO 3452

Magnetic-particle examination shall be carried out in accordance with EN ISO 17638

by welding supervisor

test

b The extent of NDT depends on the representative random sample on the basis of the total number of weld

joints made by a welder during the course of one year

c The pipeline operator shall specify the extent of non-destructive testing taking into account the design

conditions, for example:

— external loads in addition to internal pressure;

— supports;

— expansion due to temperature;

— earthquake risk

d Where welds with incomplete penetration are used, the pipeline operator can require 100 %

e Seams shall be tested 100 % by two different inspection techniques

f For branches and nozzles, consideration should be given by the pipeline operator to these methods

8.3 Non-destructive testing and assessment levels

The method or combination of methods for visual and other non-destructive testing of the welds shall be

specified by the pipeline operator Prior to commencement of welding, the non-destructive testing procedures

shall be submitted to the pipeline operator for acceptance Inspection test methods may be replaced by other

methods, if agreed by the pipeline operator Non-destructive testing procedure shall be approved by a NDT

expert Level III according to EN ISO 9712 for the appropriate examination technique

Other forms of non-destructive testing can be required, depending on the material used, the design and/or the

welding technique

Visual examination of welds shall be carried out in accordance with EN ISO 17637 Supplementary

information is given in Annex E

Radiographic examination shall be carried out in accordance with EN ISO 17636-1 and EN ISO 17636-2 If

not otherwise agreed by the pipeline operator, the image quality class given in EN ISO 17636-1 and EN

ISO 17636-2 shall be:

— Class A for categories B and C;

— Class B for Category D

Ultrasonic impulse echo examination shall be carried out in accordance with EN ISO 17640 For wall

thickness from 6 mm to 8 mm guidance is given in Annex F

Ultrasonic TOFD examination according to EN ISO 10863 may be used for detection and sizing of weld

defects and defects adjacent to the weld Supplementary specification on EN ISO 10863 is given in Annex C

In welding process numbers 114, 135 and 136 given in EN ISO 4063, additional ultrasonic testing can be

applied

Dye-penetrant examination shall be carried out in accordance with EN ISO 3452

Magnetic-particle examination shall be carried out in accordance with EN ISO 17638

Figure 1 indicates the documents in which the criteria for execution, extent and acceptance for various destructive testing methods are given

non-a Type of reference block to be agreed

The pipeline operator shall specify the acceptance criteria

The acceptance criteria given in Table G.1 for radiographic findings and in Table G.5 for ultrasonic findings are based on workmanship criteria The pipeline operator can use EPRG guidelines (see G.3) or alternative acceptance criteria based on fracture mechanics analysis and fitness-for-purpose criteria, provided they are fully documented and based on a proven safe approach

Weld defects detected by means of ultrasonic examination shall be evaluated in accordance with the requirements of Table G.6

The acceptance requirements for alternative examination methods shall be determined from case to case

8.6 Recording of test results

A clear relationship shall exist between the examination report, the test data (e.g radiographs, AUT data TOFD scans, etc.) and the weld under examination, and shall be indicated in a sketch or pipe logbook

9 Documentation

9.1 General

To prove that the welding requirements and test provisions according to this standard are fulfilled, all relevant information shall be documented This documentation shall be compiled in such a way that traceability is ensured

For detailed documentation requirements reference is made to 10.5 and 11.8

9.2 Archiving requirements

Documentation shall be archived in accordance with the pipeline operator's policy

10 Specific requirements for gas infrastructure with a MOP up to and including

16 bar

10.1 General

The following contains specific requirements for the welding and inspection of gas pipelines with a MOP up to and including 16 bar

NOTE Gas infrastructure with a MOP up to and including 16 bar is generally dedicated to gas distribution

Table 1 defines the quality requirement categories

10.2 Welders

Welders shall be certified in accordance with EN 287-1, taking into account the essential variables as laid down in Clause 6, by an accredited certification body An example of welder's qualification is given in Annex A

For gas welding (welding process 311, given in EN ISO 15609-2) the pipeline operator shall define welders' qualification requirements

Welders employed in the installation of buried pipelines shall have passed their welding examination under site conditions This requirement is deemed to have been fulfilled if the examination is conducted in an area which simulates a pipe trench of the following dimensions:

— maximum length: 1,5 m;

— maximum spacing between pipe wall and trench bottom: 0,4 m;

— maximum spacing between pipe wall and trench wall: 0,5 m

The welder's certificate shall clearly indicate, by reference to this standard, that the welder's qualification test has been performed under the conditions mentioned above

8.6 Recording of test results

A clear relationship shall exist between the examination report, the test data (e.g radiographs, AUT data

TOFD scans, etc.) and the weld under examination, and shall be indicated in a sketch or pipe logbook

9 Documentation

9.1 General

To prove that the welding requirements and test provisions according to this standard are fulfilled, all relevant

information shall be documented This documentation shall be compiled in such a way that traceability is

ensured

For detailed documentation requirements reference is made to 10.5 and 11.8

9.2 Archiving requirements

Documentation shall be archived in accordance with the pipeline operator's policy

10 Specific requirements for gas infrastructure with a MOP up to and including

16 bar

10.1 General

The following contains specific requirements for the welding and inspection of gas pipelines with a MOP up to

and including 16 bar

NOTE Gas infrastructure with a MOP up to and including 16 bar is generally dedicated to gas distribution

Table 1 defines the quality requirement categories

10.2 Welders

Welders shall be certified in accordance with EN 287-1, taking into account the essential variables as laid

down in Clause 6, by an accredited certification body An example of welder's qualification is given in

Annex A

For gas welding (welding process 311, given in EN ISO 15609-2) the pipeline operator shall define welders'

qualification requirements

Welders employed in the installation of buried pipelines shall have passed their welding examination under

site conditions This requirement is deemed to have been fulfilled if the examination is conducted in an area

which simulates a pipe trench of the following dimensions:

— maximum length: 1,5 m;

— maximum spacing between pipe wall and trench bottom: 0,4 m;

— maximum spacing between pipe wall and trench wall: 0,5 m

The welder's certificate shall clearly indicate, by reference to this standard, that the welder's qualification test

has been performed under the conditions mentioned above

10.3 Welding supervisory personnel

A welding specialist qualified to EN ISO 14731 is qualified as a welding supervisor monitoring welding work on site is (see Table 2)

For welding work in quality requirement Category B (see Table 1), a practitioner welder with several years specialised technical experience may act as a welding supervisor

10.4 Production welding

10.4.1 General

If feasible, working pits or bell holes should be constructed in the pipe trench They should have a minimum free length of 1,5 m at the weld area The distance from pipe to bell hole bottom should be not less than 0,4 m and from pipe to trench wall not less than 0,6 m

Bell holes shall be kept free of water during welding work

Segmental cuts up to 7,5° (tangents up to 15°) are permitted for pipelines and systems for quality requirement Category B Segmental cuts up to 2,5° (tangents up to 5°) are permitted for pipelines and systems in quality requirement Category C

In areas subject to ground movements and at unconcealed pipe spans and at pipelines on bridges, changes

of direction using segmental cuts shall not be permitted

The welding of alignment aids and similar temporary attachments onto pipelines should be avoided If necessary, alignment aids and similar temporary attachments may be used with the approval of the pipeline operator

10.4.3 Welding

All welding, including repairs and welding of patches for repair, shall be carried out in accordance with the approved welding specification (welding process 311, given in EN ISO 15609-2) Gas welding may be applied for pipes with an operating pressure less than or equal to 100 mbar

10.5 Requirements for records and documentation

The following documents should be made available:

a) welding procedure specification;

b) welding procedure qualification record;

c) pipe logbook (only for Category C);

d) non-destructive testing reports and / or data;

e) radiographs;

f) pipe routing (as built)

11 Specific requirements for gas infrastructure with a MOP greater than 16 bar

11.1 General

This clause contains specific requirements for the welding and inspection of gas pipelines with a MOP greater than 16 bar These welding aspects shall be taken into account in order to reduce the risk of weld defects Table 1 shows the area of application

NOTE Gas infrastructure with a MOP greater than 16 bar is generally dedicated to gas transmission

11.2 Welders

Welders shall be certified in accordance with EN 287-1, taking into account the essential variables as laid down in Clause 6 by an accredited certification body An example of welder's qualification is given in Annex A

If the pipeline operator has justifiable doubts regarding the skill of a welder in respect of the welding work to

be performed, requalification with additional requirements can be required

11.3 Welding supervisory personnel

The monitoring of welding work on site may be delegated from the welding engineer in charge to a welding specialist qualified to EN ISO 14731, according to Table 2

11.4 Qualification of welding procedures

11.4.2 Filler material requirements for welding procedure qualification

As pipelines are subject to external forces, care shall be taken to ensure that weld defects cannot become critical due to these forces

e) radiographs;

f) pipe routing (as built)

11 Specific requirements for gas infrastructure with a MOP greater than 16 bar

11.1 General

This clause contains specific requirements for the welding and inspection of gas pipelines with a MOP greater

than 16 bar These welding aspects shall be taken into account in order to reduce the risk of weld defects

Table 1 shows the area of application

NOTE Gas infrastructure with a MOP greater than 16 bar is generally dedicated to gas transmission

11.2 Welders

Welders shall be certified in accordance with EN 287-1, taking into account the essential variables as laid

down in Clause 6 by an accredited certification body An example of welder's qualification is given in Annex A

If the pipeline operator has justifiable doubts regarding the skill of a welder in respect of the welding work to

be performed, requalification with additional requirements can be required

11.3 Welding supervisory personnel

The monitoring of welding work on site may be delegated from the welding engineer in charge to a welding

specialist qualified to EN ISO 14731, according to Table 2

11.4 Qualification of welding procedures

11.4.1 General

The pipeline operator shall specify the requirements for the approval of the welding procedure according to

relevant EN ISO as per Table 2

The welding procedure specification shall be in accordance with EN ISO 15609-1 and be submitted to the

pipeline operator for approval prior to commencement of welding

Welding procedures shall be qualified in accordance with EN ISO 15614-1 or, as specified by the pipeline

operator, according to EN ISO 15613, in case of:

— welding work on materials which have not been qualified by standard procedures according to EN

ISO 15612;

— special designs

In automated and/ or mechanised welding of material with a yield strength of Rt0,5 360 N/mm2 and over,

calibrated electronic automated registration devices shall be used

11.4.2 Filler material requirements for welding procedure qualification

As pipelines are subject to external forces, care shall be taken to ensure that weld defects cannot become

critical due to these forces

For steel grades L 485 and L 555 according to EN ISO 3183, matching of base and filler materials is required For the other steel grades the use of Table 3 is recommended

Testing shall be carried out in accordance with Table 3

11.4.3 Impact testing

In addition to EN ISO 15614-1, the following requirements are prescribed for the weld metal notched in the centre of the weld and in the heat-affected zone

a) Minimum impact energy:

— Steel grades with specified minimum yield strength less or equal to 360 N/mm2

30 joules individual shall be used (see Table G.3)

In addition to the above-mentioned documents, for all pipe wall thicknesses greater than 5 mm testing is required Where subsidiary tests are necessary because of limited wall thickness, the measured impact

energy (KVP) shall be stated together with the test piece cross-section (S P) measured under the notch in square millimetres

For comparison with the requirements specified above, the measured energy shall be converted to the impact

energy KV (in joules) using the formula:

p p

KV is the impact energy for the full-size specimen, in joules;

KVP is the measured impact energy, in joules;

SP is the cross-section measured under the notch, in square millimetres

The specimen shall be as thick as possible

The verification test temperature shall be equal to the minimum design temperature or, if agreed, to the minimum exposure temperature which can occur

11.4.4 Transverse tensile test

The tensile strength of the joint, including the fusion zone of each specimen, shall be equal to or greater than the specified minimum tensile strength of the pipe material If the specimen breaks in the weld metal, it shall

be considered acceptable provided that the specified minimum tensile strength of the pipe material has been achieved

11.4.5 All-weld-metal tensile test

If an all-weld-metal tensile test is specified, the test specimen and the tests shall be in accordance with the appropriate European Standard Yield strength shall be equal to or higher than the specified minimum yield strength of the parent metal

11.5 Production welding

11.5.1 General

If feasible, working pits or bell holes should be constructed in the pipe trench They should have a minimum free length of 1,5 m at the weld area The distance from pipe to bell hole bottom should be not less than 0,4 m and from pipe to trench wall not less than 0,6 m

Bell holes shall be kept free of water during welding work

Pipes, pipeline parts and other components which require marking shall be restamped or remarked next to the cutting line prior to cutting

The minimum length of a single pipe to be welded into a pipeline shall be 0,5 times DN

Where forged fittings are used in a tie-in situation, the fittings should have pipe-pups welded to them before welding into the line so that the final tie-in is a pipe-to-pipe joint

Segmental cuts shall be limited to 1,5° (tangents up to 3°) When segmental cuts are used, only manual welding shall be allowed

Changes of direction by segmental cuts are not permitted in areas subject to ground movements, at unconcealed pipe spans and at pipelines on bridges

11.5.2 Joint preparation

Absence of laminations shall be proven by ultrasonic testing or other appropriate means, before branches, nozzles and structural parts are welded onto pipelines or other components and before cutting is carried out (see Annex B)

Pipes and pipeline components shall be clamped in such a way that strain due to movement on the weld during welding is avoided

The welding of alignment aids and similar temporary attachments onto pipelines are not acceptable

11.5.3 Welding

During welding, particular attention shall be paid to:

— preheat temperature;

— the time lapse between runs;

— the number of runs before work can be interrupted;

— the total time for weld completion;

be considered acceptable provided that the specified minimum tensile strength of the pipe material has been

achieved

11.4.5 All-weld-metal tensile test

If an all-weld-metal tensile test is specified, the test specimen and the tests shall be in accordance with the

appropriate European Standard Yield strength shall be equal to or higher than the specified minimum yield

strength of the parent metal

11.5 Production welding

11.5.1 General

If feasible, working pits or bell holes should be constructed in the pipe trench They should have a minimum

free length of 1,5 m at the weld area The distance from pipe to bell hole bottom should be not less than 0,4 m

and from pipe to trench wall not less than 0,6 m

Bell holes shall be kept free of water during welding work

Pipes, pipeline parts and other components which require marking shall be restamped or remarked next to the

cutting line prior to cutting

The minimum length of a single pipe to be welded into a pipeline shall be 0,5 times DN

Where forged fittings are used in a tie-in situation, the fittings should have pipe-pups welded to them before

welding into the line so that the final tie-in is a pipe-to-pipe joint

Segmental cuts shall be limited to 1,5° (tangents up to 3°) When segmental cuts are used, only manual

welding shall be allowed

Changes of direction by segmental cuts are not permitted in areas subject to ground movements, at

unconcealed pipe spans and at pipelines on bridges

11.5.2 Joint preparation

Absence of laminations shall be proven by ultrasonic testing or other appropriate means, before branches,

nozzles and structural parts are welded onto pipelines or other components and before cutting is carried out

(see Annex B)

Pipes and pipeline components shall be clamped in such a way that strain due to movement on the weld

during welding is avoided

The welding of alignment aids and similar temporary attachments onto pipelines are not acceptable

11.5.3 Welding

During welding, particular attention shall be paid to:

— preheat temperature;

— the time lapse between runs;

— the number of runs before work can be interrupted;

— the total time for weld completion;

— the welding energy for root pass for downhill welding with cellulosic electrodes

In cases where tie-in welds are not subjected to hydrostatic testing and when welding steel grades from

material with yield strength !Rt0,5" greater than 360 N/mm2, cellulosic electrodes shall be permitted if approved by the pipeline operator

11.5.4 Repairs of weld defects

When an external repair of the root is carried out, it shall be made in accordance with a qualified procedure

If a test of a repair weld shows that the area is still defective, the seam shall be cut out and re-welded unless otherwise agreed by the pipeline operator

11.5.5 Welding consumables

Welding consumables shall be certified as “type 3.1” according to EN 10204 The chemical composition and mechanical tests as specified in the applicable standard for the welding consumable shall be listed in the certificate

11.6 Destructive testing of production welds

The minimum number of production welds to be tested shall be in accordance with Table 5 The destructive tests shall be in accordance with EN ISO 15614-1

A cut out weld shall be representative for all the production welds

If one of the results is not acceptable, further investigations, approved by the pipeline operator, shall be made

in order to:

— define the cause of the unacceptable results;

— identify the unacceptable part(s) of the pipeline;

— analyse the consequences of the results

The pipeline operator shall decide on the acceptance of the pipeline

Table 5 — Minimum number of production test welds as function of pipeline length

For radiographic examination reference can be made to Table G.1 or Table G.3

For ultrasonic examination reference can be made to Tables G.3 or Table G.4

When welding level grades from material with yield strength !Rt0,5" greater than 360 N/mm2 with wall thicknesses greater than 10 mm and diameter greater than or equal to 300 mm which are not pressure-tested,

then welds shall also be ultrasonically examined (see Table 4, Note 5) In case of welding with cellulosic electrodes, this examination shall not be carried out sooner than 24 h after the welding has been completed unless soaking is performed

In case the pipeline operator uses EPRG guidelines (see G.2) or alternative acceptance criteria based on fracture mechanics analysis and fitness-for-purpose criteria it is recommended to perform the non-destructive testing of the welds by combination of two different examination techniques

11.8 Requirements for records and documentation

Documentation for each single weld joint shall be compiled for traceability purposes and shall include identification of the welders employed and the welds produced by them

The documents as listed below shall be verified and checked prior to commissioning

Records and documentation shall include:

a) requirements of the relevant authorities;

b) approval on the welding site;

c) contractual conditions;

d) planning and execution documentation;

EXAMPLE 1 specifications, welding instructions, calculations and computations, design plans, part lists

e) approval/certificate of suitability, also for subcontractors and suppliers, if applicable;

f) qualification of welding personnel:

1) qualification of welding supervisory personnel according to EN ISO 14731 and area of responsibility

of welding supervisory body;

2) qualification of welders (welder's certificate);

3) qualification of operators according to EN 1418;

g) qualification of test personnel:

1) qualification of test supervisory body according to the appropriate European Standard and area of responsibility of test supervisory body;

2) qualification of test personnel according to EN ISO 9712;

h) documentation of welding procedures

1) welding procedure specifications (WPS);

2) protocol for approval of welding procedure (WPQR);

i) certificates, authorisations, delivery confirmation for semi-finished products and components;

j) written records on the execution of heat-treatment operations;

k) test records:

then welds shall also be ultrasonically examined (see Table 4, Note 5) In case of welding with cellulosic

electrodes, this examination shall not be carried out sooner than 24 h after the welding has been completed

unless soaking is performed

In case the pipeline operator uses EPRG guidelines (see G.2) or alternative acceptance criteria based on

fracture mechanics analysis and fitness-for-purpose criteria it is recommended to perform the non-destructive

testing of the welds by combination of two different examination techniques

11.8 Requirements for records and documentation

Documentation for each single weld joint shall be compiled for traceability purposes and shall include

identification of the welders employed and the welds produced by them

The documents as listed below shall be verified and checked prior to commissioning

Records and documentation shall include:

a) requirements of the relevant authorities;

b) approval on the welding site;

c) contractual conditions;

d) planning and execution documentation;

EXAMPLE 1 specifications, welding instructions, calculations and computations, design plans, part lists

e) approval/certificate of suitability, also for subcontractors and suppliers, if applicable;

f) qualification of welding personnel:

1) qualification of welding supervisory personnel according to EN ISO 14731 and area of responsibility

of welding supervisory body;

2) qualification of welders (welder's certificate);

3) qualification of operators according to EN 1418;

g) qualification of test personnel:

1) qualification of test supervisory body according to the appropriate European Standard and area of

responsibility of test supervisory body;

2) qualification of test personnel according to EN ISO 9712;

h) documentation of welding procedures

1) welding procedure specifications (WPS);

2) protocol for approval of welding procedure (WPQR);

i) certificates, authorisations, delivery confirmation for semi-finished products and components;

j) written records on the execution of heat-treatment operations;

k) test records:

1) non-destructive testing and destructive tests;

2) soundness and strength tests;

l) report on special features of construction work as well as on special measures;

EXAMPLE 2 work under difficult conditions such as adverse, cramped conditions

m) inventory and location of components;

For construction in a station the following requirements do not apply:

— examination of welders under site conditions (see 10.2);

— general requirements for working pits or bell holes (see 10.4, 11.5.1);

— destructive testing (see 11.6)

Additional measures can be required in certain circumstances

EXAMPLE 1 when design temperature or vibration are considered critical

EXAMPLE 2 when special materials are used for pipes and/or pipework

EXAMPLE 3 when different grades of steel are being welded together

A pipeline welder proofs his skills/competence following the qualification procedure as given in this annex

In the case of fully mechanised processes, before execution of the approval test, welders should be examined about functional knowledge appropriate to the welding unit as specified in Annex B of EN 1418:1997

A.2 Approval test

A.2.1 Execution of the approval test

a) Welding shall be carried out according to an approved welding procedure specification

b) The test pipes to be welded should be pipeline steel grades

c) Filler material shall be approved, certified and commercially available

d) Welding technique should be:

— single side no backing (ss nb) or

— single side with backing (ss mb) or

— both sides (bs)

e) Welding shall be performed in an area which simulates a pipe trench of the following maximum dimensions:

— trench length: 1,5 m;

— spacing between pipe wall and trench bottom: 0,4 m;

— spacing between pipe wall and trench wall: 0,5 m

f) For pipes less than DN 400 the welder should complete the whole circumference of a joint

g) For pipes equal or greater than DN 400 the welder should weld half the circumference of the joint (12 to

6 o‘clock position) This proofs that the welder is qualified to weld over the entire circumference

A.2.2 Range of test pieces

Pipeline welders shall perform a test for the particular type of application Parameters could be:

— Welding process;

A pipeline welder proofs his skills/competence following the qualification procedure as given in this annex

In the case of fully mechanised processes, before execution of the approval test, welders should be examined

about functional knowledge appropriate to the welding unit as specified in Annex B of EN 1418:1997

A.2 Approval test

A.2.1 Execution of the approval test

a) Welding shall be carried out according to an approved welding procedure specification

b) The test pipes to be welded should be pipeline steel grades

c) Filler material shall be approved, certified and commercially available

d) Welding technique should be:

— single side no backing (ss nb) or

— single side with backing (ss mb) or

— both sides (bs)

e) Welding shall be performed in an area which simulates a pipe trench of the following maximum

dimensions:

— trench length: 1,5 m;

— spacing between pipe wall and trench bottom: 0,4 m;

— spacing between pipe wall and trench wall: 0,5 m

f) For pipes less than DN 400 the welder should complete the whole circumference of a joint

g) For pipes equal or greater than DN 400 the welder should weld half the circumference of the joint (12 to

6 o‘clock position) This proofs that the welder is qualified to weld over the entire circumference

A.2.2 Range of test pieces

Pipeline welders shall perform a test for the particular type of application Parameters could be:

— Welding process;

— Welding position;

— Filler material (including combinations);

— Pipe material

For an overall qualification for all diameters the welder shall perform as a minimum two different diameters in

at least two positions

EXAMPLE the combinations PC/PF or PC/PG according to EN ISO 6947

For (cellulosic or basic) downhill or flux cored arc welding the diameters shall be:

— DN 150 with a wall thickness in the range from 4,5 mm to 9 mm and

— 400 ≤ DN ≤ 800 with wall thickness > 10 mm

For other processes the dimensions should be:

— 50 ≤ DN ≤ 150 with wall thicknesses between 3,6 mm and 9 mm and

— 400 ≤ DN ≤ 800 with wall thickness > 10 mm

Additionally, one DN 50 weldolet or equivalent in position PC on a pipe of at least DN 400 should be welded

A.2.3 Supervision of execution of approval test

The pipeline operator shall nominate an examiner to supervise the execution of the approval test

The supervisor ensures that:

— the welder is identified by an appropriate document (e.g identity card);

— clear identification marks are present on the pipe before welding starts;

— repairs are not allowed during the approval test

A.3 Inspection A.3.1 General

Both non-destructive and destructive testings are required In case of NDT the quality shall meet the requirements of the standards referred to in Figure 1

After finishing welding, the examiner shall execute visual examination

All test pieces shall be X-rayed according to EN 287-1 and examined according to Table G.1, quality requirement Category D

For automatic processes (metal active gas (MAG) welding/ metal inert gas (MIG) welding) ultrasonic examination shall be carried out instead of radiography, when the wall thickness exceeds 8 mm Weld quality should meet the requirements of G.3

The weldolet shall be subjected to Magnetic Particle examination

A.3.2 Testing girth welds

Mechanical testing shall be performed on each part of the joint welded in the relevant welding position according to EN 287-1

The four bend or fracture test pieces of 400 ≤ DN ≤ 800 test weld shall be taken from the 1, 3, 4 and 5 o‘clock positions

For welder qualification tests in diameters smaller as DN 100, the weld test pieces shall be taken in accordance with EN 287-1

For cellulosic welds, a degassing heat treatment of 250 °C for up to 10 h is recommended on transverse bend test specimens

A.3.3 Testing weldolets

Four macro specimens shall be taken from the fillet weld

A.4 Approval range

A.4.1 General

If the welding test includes all dimensions and techniques as mentioned A.2.1 and A.2.2, the welder is qualified according to this standard for welding all pipelines in all diameters, wall thicknesses and pipe material according to EN ISO 3183 for the relevant procedures and positions

Separate qualifications can be performed according to dimension ranges or techniques (see below)

The welder is only qualified to use the type of filler material used in the approval test

EXAMPLE Cellulosic only qualifies cellulosic

A.4.2 Dimension ranges

When separate qualifications are performed the range is as follows:

— DN 50 qualifies all diameters up to and including DN 100 (category: small diameter);

— DN 150 qualifies all diameters between DN 100 and up to and including DN 250 (category: medium diameter);

— DN 400 qualifies equal to or greater than DN 250 (category: large diameter)

A.4.3 Techniques

When separate qualifications are performed the techniques are the following:

— single side without backing (ss nb) qualifies single side with or without backing and both sides (bs);

— single side with backing (ss mb) only qualifies single side with backing;

— both sides (bs) qualifies both side and single side with backing (ss mb)

A.3.2 Testing girth welds

Mechanical testing shall be performed on each part of the joint welded in the relevant welding position

A.3.3 Testing weldolets

Four macro specimens shall be taken from the fillet weld

A.4 Approval range

A.4.1 General

If the welding test includes all dimensions and techniques as mentioned A.2.1 and A.2.2, the welder is

qualified according to this standard for welding all pipelines in all diameters, wall thicknesses and pipe

material according to EN ISO 3183 for the relevant procedures and positions

Separate qualifications can be performed according to dimension ranges or techniques (see below)

The welder is only qualified to use the type of filler material used in the approval test

EXAMPLE Cellulosic only qualifies cellulosic

A.4.2 Dimension ranges

When separate qualifications are performed the range is as follows:

— DN 50 qualifies all diameters up to and including DN 100 (category: small diameter);

— DN 150 qualifies all diameters between DN 100 and up to and including DN 250 (category: medium

diameter);

— DN 400 qualifies equal to or greater than DN 250 (category: large diameter)

A.4.3 Techniques

When separate qualifications are performed the techniques are the following:

— single side without backing (ss nb) qualifies single side with or without backing and both sides (bs);

— single side with backing (ss mb) only qualifies single side with backing;

— both sides (bs) qualifies both side and single side with backing (ss mb)

A.5 Certificate A.5.1 General

The pipeline welder certificate shall be similar to that proposed in EN 287-1

The certificate should clearly indicate by reference to this standard that the welders' certification test has been performed under the conditions stated in Annex A

The original certificate is non-transferable and shall be directly in the possession of the welder or the contractor during execution of the work

The examiner present during test welding shall sign and stamp the original certificate

A.5.2 Duration of validity

EN 287-1 applies for the duration of validity for the certificate

Non-destructive testing (NDT) records shall be maintained according to small, medium and large pipe size categories, for the purpose of extending the validity of the welder certificates

Annex B

(informative)

Testing of lamination defects

For lamination tests the following test methods can be used:

— examination of weld preparations

— ultrasonic testing;

— magnetic particle testing (MPT);

— dye penetrants testing;

— examination of base material

— ultrasonic testing

When ultrasonic testing is performed, wall thickness measuring instruments are not allowed

The following aspects shall be considered:

— transmitter/receiver dual element probes or a single-element probe with a detection zone greater than the near field zone;

— ability to detect a flat-bottom hole of 2 mm diameter at a depth of 40 % of wall thickness through to the respective rear wall;

Test methods and acceptance criteria shall be in accordance with Figure 1 In case of lamination beyond the acceptance criteria the weldability and impact on integrity shall be verified