Dev-Aad-mp-sp-jpk-1058 Rev b2 Welding and Ndt of Cs Linepipe to Bs 4515-1 (2004)

CLIENT

PROJECT

ANDREW DEVELOPMENT PROJECT & DEVENICK DEVELOPMENT PROJECT DOCUMENT TYPE

SPECIFICATION TITLE

PROJECT NO.

06-3022.01 / 06-2999.01 REF.

ANDREW: 06-3022-01-K-1-013 DEVENICK: 06-2999-01-K-1-015

WELDING AND NDT OF CARBON STEEL LINEPIPE TO BS 4515-1(2004)

NO. OF SHEETS

77

ANDREW DOCUMENT NO.

DEV-AAD-MP-SP-JPK-1058

DEVENICK DOCUMENT NO.

DEV-DEV-MP-SP-JPK-1072

STAMP

B2

09/09/2009

RE-ISSUED FOR RFP

DC

SE

ACH

CBN

B1

28/08/2009

ISSUED FOR RFP

DC

CF

ACH

RR

A2

28/07/2009

RE-ISSUED FOR COMMENT

DC

AL

AH

CBN

A1

30/03/2009

ISSUED FOR COMMENT

SE

GAS

AWL

CBN

REV

DATE

REVISION

BY

CHK

LE

QA

PM

COMMENTS SHEET REVISION A1

DATE 30/03/2009

COMMENTS

A2

28/07/2009

RE-ISSUED FOR COMMENT. Format amended to incorporate ADD and Devenick projects. Specification revised to incorporate client comments and a statement added relating to ETP compliance.

B1

28/08/2009

ISSUED FOR RFP Revised as per client comments.

B2

09/09/2009

RE-ISSUED FOR RFP Section 2.0 – Revised technical deviation number. Section 4.2s – Revised paragraph to include welding of spools. Section 8.3.6 – Revised paragraph pertaining to post test metallography. Section 12.1 – Revised technical content. Section 13.1 – Revised technical content.

ISSUED FOR COMMENT

DEV-AAD-MP-SP-JPK-1058 Rev B2 DEV-DEV-MP-SP-JPK-1072 Rev B2

BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004)

WELDING AND NDT OF CARBON STEEL LINEPIPE TO BS 4515-1(2004) Table of Contents U

1.0

INTRODUCTION ........................................................................................................4

1.1

Purpose of Document .....................................................................................................4

1.2

Safety..............................................................................................................................4

1.3

Definitions .......................................................................................................................4

1.4

Abbreviations ..................................................................................................................5

1.5

HSEQ for Pipeline Welding Operations..........................................................................7

1.6

Pre-Production Consultation...........................................................................................8

1.7

Duties of the Contractor..................................................................................................8

1.8

Quality Conformance ......................................................................................................8

1.9

Records...........................................................................................................................9

1.10

Contractor’s Personnel ...................................................................................................9

2.0

NORMATIVE REFERENCES...................................................................................12

2.1

Specification Compliance .............................................................................................12

2.2

Conflict of Information...................................................................................................12

2.3

Revisions ......................................................................................................................13

2.4

Referenced Documents................................................................................................13

2.5

Codes and Standards ...................................................................................................13

3.0

TERMS AND DEFINITIONS.....................................................................................16

3.1

General .........................................................................................................................16

4.0

INFORMATION AND REQUIREMENTS TO BE APPROVED AND DOCUMENTED17

4.1

Information to be Supplied by the Company ................................................................17

4.2

Items subject to approval by the Company ..................................................................20

5.0

EQUIPMENT ............................................................................................................26

6.0

WELDING PROCESSES .........................................................................................27

Page 1 of 75



6.1

General .........................................................................................................................27

6.2

Automatic (Mechanised) Welding.................................................................................27

7.0

WELDING CONSUMABLES....................................................................................29

7.1

General .........................................................................................................................29

7.2

Storage and Handling ...................................................................................................29

8.0

TESTING, QUALIFICATION AND ACCEPTANCE OF WELDING PROCEDURES FOR BUTT WELDS .................................................................................................31

8.1

General .........................................................................................................................31

8.2

Changes Affecting Qualification and Approval (Essential Variables) of butt welds .....35

8.3

Destructive Testing .......................................................................................................39

9.0

TESTING, QUALIFICATION AND APPLICATION OF WELDING PROCEDURE FOR FILLET WELDING ...........................................................................................46

9.1

Non-Destructive Testing of Fillet Welds .......................................................................46

9.2

Destructive Testing of Fillet Welds ...............................................................................46

10.0

TESTING, QUALIFICATION AND APPROVAL OF WELDERS..............................47

10.1

General .........................................................................................................................47

10.2

Butt Joints .....................................................................................................................47

10.4

Fillet Welds for Sleeves, Sockets, Slip-on Flanges or Other Attachments ..................48

10.5

Changes Affecting Qualification and Acceptance (Essential Variables) of Welders....48

10.6

Non-Destructive Testing ...............................................................................................48

10.7

Destructive Testing .......................................................................................................48

11.0

PRODUCTION WELDING .......................................................................................50

11.1

Proximity of Welds ........................................................................................................50

11.2

Pipe End Preparation....................................................................................................50

11.3

Fusion Faces ................................................................................................................51

11.4

Alignment ......................................................................................................................51

11.5

Line-Up Clamps and Pipe Supports .............................................................................51 Page 2 of 75



11.6

Tack Welds ...................................................................................................................52

11.8

Stray Arcs .....................................................................................................................53

11.9

Weather Conditions ......................................................................................................54

11.10 Preheating and Post Weld Heat Treatment..................................................................54 11.11 Branches.......................................................................................................................56 11.12 Inter-run Cleaning .........................................................................................................57 11.13 Partially Completed Joints ............................................................................................57 11.14 Fillet Weld Attachments ................................................................................................57 11.15 Records.........................................................................................................................57 12.0

INSPECTION AND TESTING OF WELDS ..............................................................59

12.1

General .........................................................................................................................59

12.2

Personnel Qualification.................................................................................................61

12.4

Radiographic Testing....................................................................................................61

12.5

Manual Ultrasonic Testing ............................................................................................66

12.6

Automatic Ultrasonic Testing ........................................................................................67

12.7

Magnetic Particle Testing .............................................................................................67

13.0

ACCEPTANCE AND RECTIFICATION OF WELDS ...............................................69

13.1

Non-Destructive Testing Acceptance Criteria ..............................................................69

13.2

Rectification of Welds ...................................................................................................71

ANNEX H ADDITIONAL REQUIREMENTS FOR PIPELINES SUBJECT TO HIGH STRAIN LEVELS .....................................................................................................73 H1

Introduction ...................................................................................................................73

H.2

General .........................................................................................................................73

H.3

Weld Procedure Qualification Testing ..........................................................................73

H.4

Production Welding.......................................................................................................75

Page 3 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) 1.0

INTRODUCTION 0B

1.1

Purpose of Document 14B

This specification when read in conjunction with the referenced standards, specifications, other listed documents and relevant data sheets, defines the minimum technical requirements for the field welding and NDT of carbon steel linepipe in accordance with BS 4515-1: 2004 for sour-service conditions (applicable to steel grades up to X65). Paragraph numbers in this specification correspond to BS 4515-1: 2004. Modifications to BS4515-1: 2004 are identified as Add or Modified to Read in this U

U

U

U

specification. 1.2

Safety 15B

All risks to personnel and the environment resulting from the Andrew and Devenick Projects should be As Low As Reasonably Practicable (ALARP). Safety is the primary consideration during design and all risks associated with the design shall be minimized by adhering to the relevant governing design codes, and COMPANY International procedural requirements. 1.3

Definitions 16B

Approval

Consent given in writing, on behalf of the COMPANY in advance of an event, by a person with appropriate authority.

Approval by the COMPANY does not

relieve the CONTRACTOR from any of its contractual obligations nor from having to make good any part of the item to be delivered found to be defective subsequent to COMPANY’s approval. COMPANY

BP Exploration Operating Company Ltd or any of its subsidiaries or representative agents.

CONTRACTOR

The Party contracted by the COMPANY to be responsible for the welding and NDT.

Linepipe

Generic statement covering spools, flanges and fittings.

Shall

Indicates mandatory requirements.

Should

Indicates preferred course of action.

Page 4 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) SUPPLIER/MANUFACTURER

A party which supplies materials, equipment or services to the CONTRACTOR.

1.4

Abbreviations 17B

AC

-

Alternating Current

ACCP

-

ASNT Central Certification Programme

ALARP

-

As Low as Reasonably Practicable

Ar

-

Argon

ANSI

-

American National Standards Institute

ASNT

-

American Society for Non-Destructive Testing

ASTM

-

American Society for Testing and Materials

AWS

-

American Welding Society

BAM

-

Federal Institute for Materials Research and Testing (Germany)

BGAS-CSWIP -

British Gas Approval Scheme – Certification Scheme for Welding and Inspection Personnel

BGAS Transco-

A qualified and certification system, formerly known as ERS, for Pipeline Inspection Personnel, Originally Instituted and Run by the Former British Gas Engineering Research Station, Killingworth, UK.

BINDT

-

British Institute of Non-Destructive Testing

BS

-

British Standard

C Eng

-

Chartered Engineer

CEIIW

-

Carbon Equivalent (International Institute of Welding Formula)

CO2

-

Carbon Dioxide

CSWIP

-

Certification Scheme for Welding and Inspection Personnel

CVN

-

Charpy V Notch

DC

-

Direct Current

Dipl Ing

-

Diploma Ingenieur (Europe)

DWDI

-

Double Wall Double Image

DWSI

-

Double Wall Single Image

Page 5 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) ECA

-

Engineering Critical Assessment

EN

-

European Norm

EWE

-

European Welding Engineer

FDIS

-

Document Under Review

FL

-

Fusion Line

GMAW

-

Gas Metal Arc Welding

GSFCAW

-

Gas Shielded Flux Cored Arc Welding

GTAW

-

Gas Tungsten Arc Welding

HAZ

-

Heat Affected Zone

HSE

-

Heath and Safety Executive

HSEQ

-

Health, Safety, Environmental and Quality

HV

-

Vickers Hardness

ID

-

Inside Diameter

IIW

-

International Institute of Welding

IQI

-

Image Quality Indicator

ISO

-

International Standards Organisation

IWE

-

International Welding Engineer

MDT

-

Minimum Design Temperature

mm

-

Millimetres

MPE

-

Magnetic Particle Examination

MUT

-

Manual Ultrasonic Testing

NDT

-

Non-Destructive Testing

NIST

-

National Institute of Standards and Technology (USA)

O2

-

Oxygen

OD

-

Outside Diameter

Pb

-

Lead

Pcm

-

Ito-Bessyo Formula Carbon Equivalent

Page 6 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) PCN

-

Personnel Certification in Non-Destructive Testing

PE

-

Professional Engineer

PGMAW

-

Pulsed Gas Metal Arc Welding

PQR

-

Procedure Qualification Record

pWPS

-

Preliminary Welding Procedure Specification

RE

-

Radiographic Examination

RMS

-

Root Mean Square

SAW

-

Submerged Arc Welding

SI

1.5

Statutory Instrument

SMAW

-

Shielded Metal Arc Welding

SMYS

-

Specified Minimum Yield Strength

SWE

-

Single Wall Examination

SWV

-

Single Wall Viewing

SWSI

-

Single Wall Single Image

TWI

-

The Welding Institute (UK)

UT

-

Ultrasonic Testing

VE

-

Visual Examination

WPS

-

Welding Procedure Specification

WPQ

-

Welding Procedure Qualification

WPQR

-

Welding Procedure Qualification Record

WPQT

-

Welding Procedure Qualification Test

HSEQ for Pipeline Welding Operations 18B

Welding, cutting, NDT, and associated operations shall be undertaken in a safe manner and with due regard to individual health and safety, and the minimisation of environmental impact consistent with COMPANY requirements. Welding, cutting, NDT activities, and associated operations shall feature in CONTRACTORS operational safety planning and in the safety audit schedule. ANSI Z49.1 or similar codes should be followed.

Page 7 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) Measures shall be taken to ensure adequate ventilation and control the quality of breathing air during welding operations. As a minimum, radiography operations shall conform to the Ionising Radiation Regulations 1999 (SI 1999 No. 3232) and the Approved Code of Practice and Guidance – Working with Ionising Radiation: Ionising Regulations 1999. Environmental guidance shall be taken from EN 14717 when undertaking welding and its associated processes. 1.6

Pre-Production Consultation 19B

Pre-production meetings shall be held with the COMPANY and any appropriate third-party inspection personnel in order to ensure that all parties fully understand the requirements. These meetings shall be held before welding procedure qualification testing and before commencement of fabrication. The COMPANY Welding Engineer shall be consulted at the following stages: 1. During bid evaluation to agree the basic welding and NDT methods proposed and to advise on acceptability. 2. Before weld procedure qualification for approval of the proposed welding procedures (pWPS). 3. Before production welding for approval of the final WPS. Duties of the Contractor

1.7 20B

Construction, welding and pipe-lay shall be carried out by a well trained and qualified workforce employing reliable, modern, and well maintained equipment and shall also be fully compliant with safe and environmentally sound working practices at all times. Unless advised otherwise by COMPANY welding and associated equipment including, but not limited to: heating equipment, fluxes, gases, filler metals, welding units, mechanical handling, testing equipment, and NDT equipment shall be supplied and appropriately calibrated. Be responsible for the compliance of sub-contractors with this specification. 1.8

Quality Conformance 21B

The CONTRACTOR shall demonstrate to the satisfaction of the COMPANY that his activities within the scope of this document comply with ISO 3834 Parts 1 & 2 and the relevant sections of BS EN ISO 9001. Page 8 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) Prior to the commencement of work, the CONTRACTOR shall submit to the COMPANY for review and approval, a Quality Plan and procedural specifications, which shall include procedures for storage and control of materials and welding consumables, welding and non-destructive testing and supporting qualification records. The Quality Plan shall define all sub-contractors involvement within the work. Names of individuals Welding Engineers / Welding Inspectors responsible for implementation of quality assurance and quality control functions shall be included. Records

1.9 2B

Documents required by this specification shall be gathered, collated, indexed, stored, and finally presented to COMPANY for secure long term storage. A log identifying, by number, each pipe or fitting and identifying the weld numbers joining them to other items shall be compiled. Each circumferential weld (whether a field joint or shop-made weld) shall be allocated a unique number, which shall be used for reference to the weld in reports and test documents. All documentation shall be available in an agreed, good quality, electronic format. Contractor’s Personnel

1.10 23B

1.10.1 General 73B

Personnel associated with welding including engineers, welders, welding operators, welding inspectors and non-destructive testing technicians shall be properly trained and qualified to recognised industry standards by examination and/or by individual test. 1.10.2 Welding Engineers 74B

A competent and suitably qualified Welding Engineer shall be employed. The Welding Engineer shall be responsible for the technical aspects of all welding operations including the following: 

Selection of welding processes, equipment and consumables;



Preparation and qualification of welding procedures;



Qualification of welders;



Providing technical oversight of the production welding;



Liaison with the COMPANY and the NDT SUB-CONTRACTORS.

Page 9 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) The minimum experience and qualification level for the Welding Engineer should be: Chartered Engineer (C.Eng / Dipl Ing) holding as a minimum a degree in engineering, metallurgy or materials science and having specialised training in welding technology. The requirements of ISO 14731(FDIS) / EN 719 should be met as demonstrated by the European Welding Engineer (EWE) or International Welding Engineer (IWE) qualification. Professional Membership of The Welding Institute (UK) is desirable and a minimum of 5 years relevant experience in the pipeline welding or fabrication industry is deemed essential. 1.10.3 Welding Inspectors 75B

Competent and certificated welding inspection personnel shall be employed in sufficient numbers to ensure that all welding related activities are adequately inspected. Welding Inspectors shall have a sound knowledge of welding processes and their application to pipeline welding, and possess the knowledge and skills to carry out the tasks given in the accepted Quality Plan, including those necessary for the following: 

Conduct of routine inspections and checks on site or at suppliers in a systematic manner;



Production of accurate records and reports.

Welding Inspectors shall, as a minimum, hold current certification to any of the following standards: 

CSWIP (TWI, UK) – Welding Inspector;



BGAS-CSWIP (TWI, UK) – Welding Inspector;



PCN (BINDT, UK) – Weld Inspection Level 2;



AWS QC1 (1996 or later edition) – Certified Welding Inspector (CWI).

Alternative Welding Inspector certification is unacceptable unless accepted by the COMPANY. A Senior Welding Inspector shall be employed to supervise the work of the welding inspectors. The role of senior welding inspector requires at least 10 years relevant experience and sound knowledge of welding processes and their application. Formal engineering training through apprenticeship and technical college education are required. Senior Welding Inspectors shall, as a minimum, hold current certification to any of the following standards:

Page 10 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) 

CSWIP (TWI, UK) – Senior Welding Inspector;



BGAS-CSWIP (TWI, UK) – Senior Welding Inspector (SWI) or Senior Pipeline Inspector (SPI);



PCN (BINDT, UK) – Weld Inspection Level 3;



AWS QC1 (1996 or later edition) – Senior Certified Welding Inspector (SCWI).

Page 11 of 75



NORMATIVE REFERENCES 1B

2.1

Specification Compliance 24B

This specification has been written to be in full compliance with BP GIS 43-333 “Guidance on Industry Standard BS 4515-1 2004 for Pipeline Welding”. Non-applicable paragraphs and clauses of this GIS to this specification are detailed within technical deviation (JPK-DR-002). CONTRACTOR shall be in complete compliance with the requirements of the following GIS documents unless instructed otherwise by this specification: GIS 43-311

Longitudinal or Helical Seam Submerged Arc Welded Linepipe in Grades up to X80 – Supplement to API 5L, 43rd Edition 30th May 2007.

GIS 43-312

High Frequency Induction (HFI) or Electric Resistance Welded (ERW) Linepipe in Grades up to X70 - Supplement to API 5L, 43rd Edition 30th May 2007.

GIS 43-313

Seamless Linepipe in Grades up to X80 – Supplement to API 5L, 43rd Edition 30th May 2007.

GIS 43-339

Automated Ultrasonic Testing of Pipeline Girth Welds 30th October 2007.

GIS 18-012

Guidance on Industry Standard for Storage and Control of Welding Consumables 31st October 2007.

Note: Within the GIS documents CONTRACTOR shall replace the words ‘must’ and ‘should’ with ‘shall’ to read as mandatory requirements. Any ‘shall’ or ‘must’ in commentary (text in blue italics) does not specify an ETP requirement. The CONTRACTOR is responsible for the quality of materials and workmanship in performance of the work. 2.2

Conflict of Information 25B

In the event of any conflict, inconsistency or ambiguity between the contract documents, this Specification or any other specification and associated data sheets, or with any of the applicable codes, standards and regulations the CONTRACTOR shall immediately inform the COMPANY in writing and receive written clarification from the COMPANY before preceding with the work.

Page 12 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) 2.2.1

Project Documents 76B

The following documents pertaining to the Andrew and Devenick Projects are related or applicable to this Specification: DEV-AAD-MP-DS-JPK-1055 / DEV-DEV-MP-DS-JPK-1070

Carbon Steel Induction Bends Specification

DEV-AAD-MP-SP-JPK-1056 / DEV-DEV-MP-SP-JPK-1073

Specification for Carbon Steel Flanges, Fittings and Bulkheads

DEV-AAD-MP-DS-JPK-1075 / DEV-DEV-MP-DS-JPK-1074

Methanol Injection Linepipe Data Sheet

DEV-AAD-MP-DS-JPK-1095 / DEV-DEV-MP-DS-JPK-1075

Gas Lift Linepipe Data Sheet

DEV-AAD-ME-SP-JPK-1096 / DEV-DEV-MP-SP-JPK-1015

Specification for Subsea Valves

Revisions

2.3 26B

The latest issues for the relevant standards, codes, statutory regulations and specifications referenced herein shall be applied to the work. Referenced Documents

2.4 27B

It is the responsibility of the CONTRACTOR to ensure that he has received from the COMPANY all specifications, etc which are referenced within applicable specifications to enable him to understand and comply with all aspects of the work to be performed for the COMPANY. Codes and Standards

2.5 28B

The CONTRACTOR is responsible for the quality of the work and compliance with the requirements

of

the

Specifications as listed.

applicable

International

Codes,

Statutory

Regulations

and

The following Codes, Standards and Specifications with their

latest published amendments shall apply. Statement does not apply to BS4515-1: 2004. 2.5.1

American National Standards Institute (ANSI) / American Welding Society (AWS) 7B

ANSI/AWS A4.3

Standard Methods for Determination of the Diffusible Hydrogen Content of Martensitic, Bainitic, and Ferritic Steel Weld Metal Produced by Arc Welding

ANSI/AWS A5.32

Specification for Welding Shielding Gases

ANSI/AWS C5.3

Recommended Practices for Air Carbon Arc Gouging and Cutting Page 13 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) Standard for AWS Certification of Welding Inspectors

ANSI/AWS Z49.1

Safety in Welding Cutting, and Allied Processes

2.5.2

ANSI/AWS QC1

British Standards and Regulations 78B

BS 4515-1 (2004)

Specification for welding of steel pipelines on land and offshore. Carbon and carbon manganese steel pipelines

BS EN 288:9

Specification and Approval of Welding Procedures for Metallic Materials

BS EN 1043

Destructive Testing on Welds in Metallic Materials- Hardness Testing Part 1 – Hardness Tests on Welded Joints

BS EN 10045

Charpy Impact Testing of Metallic Materials

BS EN 10204

Metallic Products – Types of Inspection Document

BS EN 12074

Welding consumables. Quality requirements for manufacture, supply and distribution of consumables for welding and allied processes

BS EN 1435

Non-Destructive

Examination

of

Welds.

Radiographic

Examination of Welded Joints BS EN ISO 14175

Welding consumables. Gases and gas mixtures for fusion welding and allied processes

BS EN 14717

Welding and allied processes. Environmental check list

BS EN ISO 15609-1

Specification and qualification of welding procedures for metallic materials. Welding procedure specification. Arc welding

2.5.3

BS EN ISO 9001

Quality Management Systems – Requirements

SI 1999 No. 3232

The Ionising Radiations Regulations 1999

International Standards Organisation 79B

ISO 2504

Radiography of Welds and Viewing Conditions for Films – Utilisation of Recommended Patterns of Image Quality Indicators (IQI’s)

ISO 3690

Welding and Allied Processes – Determination of Hydrogen Content in Ferritic Steel Arc Welds

Page 14 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) ISO 3834

Quality Requirements for Welding. Fusion Welding of Metallic Materials, Parts 1-6.

ISO 5173

Destructive Tests on Welds in Metallic Materials – Bend Tests

ISO 5580

Non-Destructive Testing – Industrial Radiographic Illuminators – Minimum Requirements

ISO 6507-1

Metallic Materials. Vickers Hardness Test. Test Method

ISO 11699-1

Non-Destructive Testing – Industrial Radiographic Films – Part 1:

Classification

of

Film

Systems

for

Industrial

Radiography ISO 14731/FDIS

Welding Co-Ordination – Tasks and Responsibilities (Under Revision)

ISO 17636

Non-Destructive Testing of Welds- Radiographic Testing of Fusion Welded Joints

ISO 17638 2.5.4

Non-Destructive Testing of Welds- Magnetic Particle Testing

Others 80B

ASTM E1815-96

Standard Test Method for Classification of Film Systems for Industrial Radiography

Page 15 of 75



TERMS AND DEFINITIONS 2B

3.1

General 29B

This document shall be read hereafter in conjunction with BS 4515-1; 2004 as clarified, amended or supplemented below.

The clause numbers used reflect correspondingly

numbered sections within. The following terms shall be Modified to Read: U

U

3.5 Contractor See 1.3 3.6 Employer For “Employer” read “COMPANY” Add: U

3.26. Batch (lot) A single heat of filler wire, a single blend of flux, or for covered electrodes or cored wire, the combination of a single heat of cored wire with a single dry blend of flux cover or core. 3.27. COMPANY See 1.3 3.28. Quality plan Document specifying which procedures and associated resources shall be applied by whom and when to a specific project, product, process or contract

Page 16 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) 4.0 4.1

INFORMATION AND REQUIREMENTS TO BE APPROVED AND DOCUMENTED 3B

Information to be Supplied by the Company 30B

Information to be supplied by the COMPANY is given as additions or clarifications to the appropriate Sections of BS 4515-1: 2004. Clause

BS 4515-1: 2004

Supplement

a

Whether batch testing of electrodes and filler materials is required.

Batch testing of electrodes and filler material is required. See sections 7.2.1 & 7.2.2 of this specification. Production welding shall utilise the same batches of consumables as those used for welding procedure qualification.

b

Whether specific compositional controls are to be applied to the deposited weld metal

All consumables will be proposed by CONTRACTOR and subject to COMPANY approval. See Section 4.2a and 7.1 of this specification.

c

The degree of yield strength overmatching for welds in pipe materials where installation methods involve plastic deformation of the pipe or for welds in pipe of specified minimum yield strength (SMYS) 500-550N/mm2.

The yield strength of welding consumables shall overmatch SMYS of the respective base material by 80MPa-200MPa. See Section 8.3.2 of this specification.

d

Whether different batches of electrodes and filler materials are to be individually identifiable and completely separated.

Different batches of electrodes and filler materials shall be individually identified and completely separated.

e

The type and number of retests required in the event of failure during testing and qualification of welding procedures.

Re-testing is permitted subject to COMPANY approval, provided the CONTRACTOR can demonstrate that the test failure was due to error in test procedure, specimen preparation or defect in the mechanical test specimen.

f

Whether an alternative location is specified for the excavation location for the repair weld test.

No alternative locations are required for repair test weld.

g

Whether strain ageing data and/or additional tests are required as the basis for welding procedure approval for pipe-reeling.

See Annex H of this specification. The use of historical data may be permitted subject to meeting the requirements of this specification and if agreed by the COMPANY.

Page 17 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) Clause

BS 4515-1: 2004

Supplement

h

Whether specimens should be allowed to cool for a duration other than 24 hours before testing.

Specimens shall be allowed to cool for 24 hours before testing.

i

The method of weld tensile testing when a minimum weld metal yield strength requirement is specified.

Tensile testing shall be in accordance with BS EN 288-9 and sections 8.2, 8.3 and 8.4 of BS 4515-1. No flattening of test pieces shall be permitted. See section 8.3.2 of this specification.

j

Charpy toughness and test temperature for conditions other than pipe and wall thicknesses up to and including 25mm, minimum design temperatures not lower than 10°C and pipe material with a specified minimum yield strength not greater than 550N/mm2.

Impact requirements as per Section 8.3.5 of BS 4515-1 and as modified by this specification.

k

Whether additional NDT methods for fillet welds apply.

There are no additional NDT requirements to visual and MPE for fillet welds.

l

Whether the hardness values of test specimens exceed those given in Table 4.

The hardness shall not exceed the sour-service criteria of Table 3 of BS EN 288-9.

m

Whether a proposed change to a welding procedure will require re-qualification of the welders.

All changes from approved weld procedures/specifications shall be subject to prior written COMPANY approval and, where necessary and appropriate, to the successful requalification of WPS and/or welders.

n

Whether prevailing weather conditions are such that quality of the completed weld would be impaired.

All welding shall be performed under conditions where protection from adverse weather conditions is assured.

o

The method(s) and frequency of visual inspection and nondestructive testing.

See section 12.1 of this specification.

p

Whether completed welds are to be ground.

Completed welds may be ground when agreed with the COMPANY to facilitate NDT provided the wall thickness complies with the minimum specified limit. Grinding shall ensure no stress raisers and a smooth transition exists.

Page 18 of 75



BS 4515-1: 2004

Supplement

q

Whether alternative techniques are to be used for radiographic testing of welded butt joints.

See section 12.4.1 of this specification.

r

Ultrasonic testing acceptance criteria


s

Whether NDT acceptance criteria are to be based on quality control or engineering critical assessment.

The use of alternative acceptance standards for girth welds shall be subject to COMPANY approval before contract award. See section 13.1.3 of this specification.

t

Whether the maximum planar defect dimension is to be less than 25mm.

No planar defects shall be permitted in the weld preparation area.

u

Whether a more stringent limit for root penetration is required.

A more stringent limit for root penetration is not required except for pipe less than 6 inch NB for which this shall be limited to 1.5mm maximum.

v

Whether different hardness limits for anode bonding joints are required for anode bonding joints.

Hardness shall be in accordance with the limits outlined within this specification.

w

The composition and thickness of the pipe corrosion resistant alloy (CRA) layer.

Not applicable.

x

The method of linepipe manufacture, including seal weld and longitudinal weld details where these items are present in CRA clad and lined pipelines.

Not applicable.

y

The maximum oxygen content of backing gas during welding or the corrosion tests that the weld is required to pass.

Not applicable.

z

Whether the strength contribution of the CRA layer has been used in the design.

Not applicable.

aa

Whether additional hardness traverses are required in CRA clad and lined pipelines.

Not applicable.

ab

Hardness limits for CRA portions of the weldment.

Not applicable

Page 19 of 75



BS 4515-1: 2004

Supplement

ac

The composition limits for chemical analysis of the weld in CRA clad and lined pipelines.

Not applicable.

ad

Whether a chemical analysis is required for seal weld qualification CRA clad and lined pipelines.

Not applicable.

ae

Whether internal weld or cutting spatter in CRA clad and lined pipelines requires removal and the method to be used.

Not applicable.

af

Whether weld root acceptance criteria more onerous than those in Table 5 are required in CRA clad and lined pipelines.

Not applicable.

ag

Whether full penetration repairs are permitted in CRA clad and lined pipelines.

Not applicable.

Whether pre-qualification trials of welding processes are required

See section 6 of this specification

ai

Whether additional hardness surveys on macro-sections are required

See section 8.3.4 of this specification

aj

Whether additional Charpy test locations are required

See section 8.3.5 of this specification

Add: ah U

4.2

Items subject to approval by the Company 31B

The items to be approved by the COMPANY are included in this Specification as additions or clarifications or amendments to the appropriate Sections of BS 4515-1: 2004. Clause

BS 4515-1: 2004

Supplement

a

Welding consumables to be used.

The maximum Ni content of the as-deposited weld metal (root) shall be in the range of 0.6% to 1.0%.

Page 20 of 75



BS 4515-1: 2004

Supplement

b

The definition of a batch when batch testing of electrodes and filler materials is required.

Batch: a single heat of filler wire, a single blend of flux, or for covered electrodes or cored wire, the combination of a single heat of cored wire with a single dry blend of flux cover or core.

c

The tensile strength of weld metal for joints between dissimilar materials, if other than that of the higher strength parent metal.

In the case of dissimilar metal welds, the weld metal shall have strength at least equal to that of the lower strength parent material.

d

The type and number of retests of a welding procedure when they are permitted.

Re-tests of a welding procedure shall only be permitted for minor deviations to specification requirements at the discretion of the COMPANY.

e

Test weld production on pipes shorter than full length.

Any proposal to carry out the test welds on pipes less than 12m long shall be subject to COMPANY approval.

f

Use of roll welding.

The use of roll welding shall not be permitted, unless agreed by COMPANY.

g

Use of a test weld for destructive testing or rewelding to the same procedure following NDT failure.

An explanation shall be given to the satisfaction of the COMPANY for the presence of any flaws in the test weld outside the specified acceptance criteria before approval is given for the test piece to be subject to destructive testing.

h

Welding procedure qualification test details and welding procedure specification for production welding.

Applicable.

i

Simulation of a fillet weld joint using flat plate fillet welds.

The simulation of a fillet weld joint using flat plate welds shall not be permitted.

j

Alternative methods of NDT for welder test piece.


k

Giving a welder a second opportunity to gain approval. All documentation relating to welder qualification tests.


l

Page 21 of 75

All documentation relating to welder qualification tests shall be approved by the COMPANY; prior to the welder being allowed to commence production work. Welder records shall be included within the as-built documentation and issued to COMPANY in electronic format. Welder records shall be kept for a period of ten years.



BS 4515-1: 2004

Supplement

m

Use of manual thermal cutting for pipe end bevelling and the ability of the operator.

Manual thermal cutting shall not be used for bevelling the pipe ends for welding.

n

The blending out by grinding of minor imperfections within the joint preparation area.

The joint shall be re-prepared in the event of small score marks, indentations, etc being present within the joint preparation area.

o

Method of marking datum points on a joint for ultrasonic testing.

The method of marking ultrasonic datum points shall be included in the ultrasonic procedure for weld examination and shall be subject to APPROVAL by the COMPANY.

p

Method of obtaining minimum misalignment, other than rotation of the pipes.

Only rotation of the pipes shall be used for obtaining minimum misalignment.

q

Method of alignment of pipes other than internal line-up clamps.

Alignment methods other than the use of internal line-up clamp shall be subject to approval by the COMPANY. See section 11.5.1 of this specification.

r

The stage at which line-up clamps are removed.

Internal line-up clamps shall not be removed until after completion of the root run and hot pass. External line-up clamps shall not be removed until at least 50% of the circumference of the joint uniformly spaced have been filled, as described in Section 11.5.1 of this specification.

s

The stage at which the pipe is lowered onto skids or support is removed from fittings.

For subsea spools, pipes shall not be moved or lifted until at least a 1/3rd of the weld has been deposited, unless it can be demonstrated as acceptable through calculation.

t

Repair of places where stray arcs have occurred.

Areas showing stray arcs may only be repaired by mechanical removal of the defective material, blending of the excavation, checking by MPE followed by confirmation that pipe or fitting wall thickness is within specified tolerances. Repair by welding shall not be permitted. Pipes not maintaining minimum wall thickness shall be rejected.

u

Means of applying pre-heat.

Approval of the proposed method of pre-heating shall be included with review of the weld procedure specification. See section 11.10.2 of this specification.

Page 22 of 75



BS 4515-1: 2004

Supplement

v

Methods of attaching removing thermocouples.

and

Thermocouples shall be attached to the pipe by the capacitance discharge method. After use, the thermocouples junctions shall be removed by grinding and the area of attachment shall be examined by MPE. Methods of thermocouple attachment and removal shall be subject to review by the COMPANY.

w

The welding procedure for branch connections where the angle between the main and branch is less than 60°.

A branch simulation test weld is required for branch welds where the angle between the main line and branch is less than 60°C.

x

Written ultrasonic examination procedure for pipe material around a planned cut-out.

Procedure to be APPROVED by COMPANY, if applicable.

y

All non-destructive testing procedures to be used.

All NDT procedures used for examination of procedure qualification and production welds shall be qualified and then subject to approval of the COMPANY.

z

All inspection personnel.

The qualification certificates of all NDT personnel shall be subject to review and approval by COMPANY.

aa

The technique in BS EN 1435 to be used for radiographic examination.

Only class B techniques of ISO 17636 shall be used, unless geometric constraints oblige relaxation to class A. The welding CONTRACTOR shall provide explanation for any non-use of class B. techniques and demonstrate their acceptability to the COMPANY.

ab

Any method for magnetic particle testing to be used at above ambient temperature.

Wet methods of magnetic particle testing shall always be used for weld assessment and acceptance purposes. Dry powder may be used for repair inspection. See Section 12.7.

ac

Any proposal to repair a weld.

The COMPANY shall approve all weld repairs.

ad

Any alternative limits on repair weld length.

The limits to the length of weld repairs shall be as specified in Section 13.2.1 of BS 4515-1, i.e. 30% of the weld length maximum for a partial penetration repair and 20% of the weld length for a full penetration repair.

ae

Use of root sealing or single run repair deposits.

Root sealing or single run repairs are not acceptable.

Page 23 of 75



BS 4515-1: 2004

Supplement

af

More than one attempt at a repair.

Only one attempt may be made at a full penetration repair of carbon manganese steel welds, provided it is qualified. Two attempts may be made at a partial penetration repair of carbon manganese steel welds provided that the repair procedure is qualified by two simulated repairs.

ag

The position of the longitudinal seam weld (if applicable) on the subsea pipeline at the hyperbaric weld location.

Not applicable. Relates to hyperbaric welding.

ah

Joining technique and equipment for brazing or aluminothermic welding of anode bonding leads.

Applicable. Pin brazing shall be used unless otherwise directed by COMPANY. Procedures for attachment of anode bonding leads shall be approved by COMPANY.

ai

Proposed brazing or aluminothermic welding procedure specification.

Refer to ah.

aj

Method of chemical analysis of butt welds in CRA clad and lined pipelines.

As ah above.

ak

The location, elements to be analysed, method and acceptance criteria for seal weld chemical analysis in CRA clad and lined pipelines.

Not applicable.

al

Whether grinding, wire brushing or filing of the internal surface of CRA clad and lined pipelines is permitted.

Not applicable.

am

Cessation of oxygen monitoring immediately prior to completion of the root pass in CRA clad and lined pipelines. The method of flaw removal in CRA clad and lined pipelines.

Not applicable.

A reduction in the number of mechanical test samples for qualification of repair weld procedures in CRA clad and lined pipelines. Use of automatic and semiautomatic welding systems

Not applicable.

an ao

ap

Page 24 of 75

Not applicable.

See section 6 of this specification.



BS 4515-1: 2004

Supplement

aq

Approval of welding consumable handling and storage procedure


ar

The mixing of Ar/CO2 shielding gas at site


as

The type of weld monitoring equipment for use during WPQ testing


at

The forms used for recording for WPQ information

See specification 8.1.6 of this specification.

au

The re-use of existing WPSs


av

Alternative etchants to Nital


aw

Acceptance of existing welder qualifications


ax

Method of coatings

end


ay

The solvent for grease removal


az

Use of internal tapering


ba

Re-start of welding following suspension due to cracking


bb

Full scale (H.3.1)

See section H.3.1 of this specification.

removing

bend

procedure

Page 25 of 75



EQUIPMENT 4B

Add U

Independent calibrated instrumentation shall be provided to measure all relevant parameters during WPQT and production. The use of permanent or consumable backing rings is not permitted. An exception is the outer pipe welds in a pipe-in-pipe system. Non-consumable temporary backing as an integral permanent feature on an internal clamp is permitted subject to satisfactory demonstration of the process. SMAW electrode holders shall be fully insulated. Welding return cables connections shall be of sufficient cross-sectional area to prevent concentration of current and shall be securely attached to prevent arc burns.

Page 26 of 75



WELDING PROCESSES 5B

Add: U

General

6.1 32B

Mechanised and automatic welding processes are preferred and should be used whenever possible for pipeline girth welding.

Main line welding should be by mechanised or

automatic gas metal arc welding (GMAW) which may include single, multi-torch, or tandemarc variants of the process and the use of cored wires.

If the use of mechanised or

automated GMAW processes are impracticable, alternative processes may be used. In such instances, welding may be performed by shielded metal arc welding (SMAW), manual or automated gas tungsten arc welding (GTAW), semi-automatic GMAW processes using solid or cored wires, or a combination of these processes. For double or multiple jointing, girth welds should be made using submerged arc welding (SAW) whenever possible. If SAW cannot be used, the alternative mainline processes listed above may be utilised either alone or in combination with SAW. The welding of pipelines by the oxy-acetylene process or by the flash-butt welding process (FBW) or by any other process not defined above is not permitted. When applicable the welding process or combination of processes proposed for the pipelay welding operation shall be specified in the bid. Manual processes, semi-automatic or automatic welding systems may be offered. If a process or system is proposed of which COMPANY has no previous experience, COMPANY will specify welding and NDT trials which shall be undertaken and completed successfully before the proposed technique can be approved for qualification testing. Separate qualification of a SMAW procedure may also be required, for possible use in the event of failure of semiautomatic or automatic equipment in production welding. 6.2

Automatic (Mechanised) Welding 3B

If mechanised or automatic processes are proposed for main line welding, tie-in welding, or multiple jointing of pipeline sub-assemblies, the bid shall include full details of the processes to be used, the associated welding equipment, and the proposed area of application. For mainline welding applications, the proposal shall list the number of welding stations (root pass to final capping pass) either on the firing line (offshore lay barge) or spool base and detail the equipment and number of welders and other personnel required to operate each station. Full details of the welding shelters shall also be provided. Page 27 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) A similar level of detail shall be provided for tie in welding and multiple jointing. Mechanised 2G or 5G welding equipment should be operated in conjunction with data logging facilities capable of recording the essential variables associated with the arc, including wire feed speeds and travel speeds. The equipment shall record all parameters for each pass of every weld at a minimum rate of once per 10 degrees of angular rotation and shall indicate the angular position of each measurement. This data shall be readily retrievable for monitoring purposes and shall form part of the pipeline construction data package. Data logging is mandatory if welding with either multi torch or multi wire systems and for girth welds made in ≥ X80 grade linepipe. Each mechanised (automatic) welding station shall be demonstrated to be fully operational before it is employed to weld any joints that will be incorporated into the pipeline. For example, for a spread of welding stations this demonstration may consist of two full girth welds made consecutively, each weld being required to meet the production acceptance criteria without the need for any repair. NDT shall utilise the agreed pipeline NDT techniques and equipment. Internal welding equipment shall also require operational demonstration. Each of these pre-construction welds shall be uniquely identified and reserved for possible mechanical evaluation by COMPANY. This operational demonstration shall be repeated as agreed with COMPANY but should, as a minimum, be repeated after interruptions ≥ 7 days in pipeline welding and when a welding spread is disassembled and transferred from one section of the line to another. The proposal shall also detail the intended level of technician support for equipment maintenance and list the principal spares that will be available in order to maintain equipment serviceability for the duration of the pipelay. The proposal shall also advise if a manual welding procedure is to be qualified for production or repair welding.

Page 28 of 75



WELDING CONSUMABLES

7.1

6B

General 34B

Add: U

The selection of electrodes, filler materials and wire/flux combinations shall be approved by the COMPANY. In principle, the yield strength of the weld metal should be selected to ensure that the yield strength of the deposited pipeline girth welds overmatches the actual yield strength of the parent pipe material. The deposited weld metal shall also meet the specified ductility, toughness, and limiting hardness criteria in accordance with this specification. The definition of a batch (lot) of consumables shall be that stated in 3.26. 7.1.1

Weld Metal Composition 81B

A weld root chemical analysis shall be carried out on each welding procedure.

The

following elements shall be reported: Carbon, Silicon, Manganese, Sulphur, Phosphorus, Chromium, Nickel, Molybdenum, Copper, Aluminum, Titanium, Vanadium, Boron, Nitrogen and any other elements deliberately added. 7.2

Storage and Handling 35B

Add: U

The storage and handling of welding consumables shall be in accordance with BP GIS 18012. A detailed consumable storage and handling plan shall be submitted for COMPANY review and acceptance. Shielding gases shall meet the requirements of BS EN ISO 14175 or AWS A5.32. Gases shall be pre-mixed and bottled by the supplier and shall have certificates of compliance. The certificates shall show the composition and dew point. Subject to COMPANY approval, standard Ar/CO2 gases may be mixed at site. 7.2.1

Consumable Batch Testing by Contractor 82B

Add: U

Each batch/lot of welding consumables shall have a consumable manufacturer’s certificate conforming to the relevant EN, ISO or AWS filler metal specification. The testing of each batch shall include actual deposited weld metal chemical composition, tensile and Charpy impact tests; refer to BP GIS 18-012 and Section 7.2.2.

Page 29 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) For low hydrogen SMAW consumables (<5ml/100g), manufacturer’s certificates shall include average-diffusible-hydrogen level as determined and reported in accordance with ISO 3690 or ANSI/AWS A4.3. All certificates shall comply with BP GIS 18-012 and EN 10204 type 3.1. SAW wire shall be tested in combination with the same brand and classification of flux as that to be used during production welding. The consumable certificates shall be examined to verify that the same weld properties can be expected for the production welds as those obtained during weld procedure testing. Additional Batch Testing by Contractor

7.2.2 83B

Add: U

Only the batches of consumables mechanically tested during qualification of the weld procedure shall be used for production welding of the following pipeline types: 

If the NDT acceptance criterion has been established by an ECA.



For pipe grades of X65 and above.



If consumables with an AWS “G” designation are used, e.g. E8010-G or ER70S-G.

Add: U

Each cast and batch of consumables for production welding shall be subjected to the following tests during qualification of weld procedures: 

2 x tensile tests to determine yield strength, ultimate tensile strength and elongation.



2 x charpy impact tests conducted in accordance with Section 8.3.5.



1 x macro-hardness survey sampled from the 3 o’clock position.



1 set of weld metal CTOD (tests required only for pipelines with ECA based acceptance criteria or if required by designer).



Weld metal chemical analysis (see section 7.1.1)

The testing shall be in accordance with Section 8.3. The results shall meet the levels required for the relevant weld procedure(s) and if applicable the ECA.

Page 30 of 75



TESTING, QUALIFICATION AND ACCEPTANCE OF WELDING PROCEDURES FOR 7B

BUTT WELDS 8.1

General 36B

Add following second paragraph: U

Welding procedure qualification test shall be carried out specifically for pipe, valve, flange and fitting materials using contract materials or COMPANY approved equivalent materials. The WPQT shall simulate the production welding and shall be undertaken as far as practicable under site ambient conditions. Add following third paragraph: U

Repair weld procedure shall be required for each type of repair expected during production. It is not necessary to make a full circumferential repair weld. It is only required to make sufficient repair weld to provide material for mechanical testing. Repairs shall comply with Figure 1 of BS 4515-1. Single pass repairs are only permitted for cap defects. Each repair type to be used in production shall be separately qualified e.g. 

Full penetration repair.



Partial penetration repair/re-repair.



Cap repair.



Internal repair (When permitted).



Intermediate repairs (Repairs made with a different process during the course of making the girth weld, e.g. SMAW repairs to an automatic root).

Individual repair weld procedure qualification excavations shall be limited to 300 mm. Excavations shall be made to simulate those expected during production using the appropriate profile and depth. Note: The excavation shall be mimicked and a drawing included within the WPQT documentation package. Add: U

Repair welds and welding to forgings shall be made using low hydrogen welding consumables/filler metals i.e. < 5ml/100g. Electrodes for SMAW shall be vacuum packed and used in accordance with the manufacturer’s recommendations.

Page 31 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) Add: U

8.1.1

Protocol for Testing 84B

Preliminary Welding Procedure Specifications (pWPSs) shall be submitted to the COMPANY before commencement of the Welding Procedure Qualification Tests (WPQTs). Prior to WPQT and production welding, meetings shall be held between the COMPANY, the CONTRACTOR and any third party inspection personnel in order to ensure that all parties fully understand the specified project requirements. All welding procedures, including repair procedures, shall be qualified by visual examination, MPE, RE, MUT/AUT and mechanical testing as specified in this specification. Welding, NDT and mechanical testing of the WPQT welds shall be witnessed by the COMPANY or an accepted third party. The witnessing of mechanical tests should include the positioning of the notches for charpy and CTOD tests. 8.1.2

Welding Procedure Specification Information 85B

The WPS shall incorporate the information required by BS EN ISO 15609-1, BS EN 288-9, and the following: 

Material manufacturer.



Arc energy.



Welding machine manufacturer, type, and model (for semi-automatic, mechanised and automatic processes).



Software version (if applicable).



Hot wire diameter, feed speed, current, and voltage (if applicable).

For multi-wire processes the following parameters shall also be specified on the WPS when applicable: 

Number and size of wires.



Electrode spacing.



Individual wire angle relative to pipe surface.



Head spacing for multi-head welding.



Offset from top dead centre for 1G rotated welding.



Direction of rotation for 1G rotated welding.

Page 32 of 75



Shroud diameter for tandem GMAW/PGMAW.

For welding processes involving multiple heads, the COMPANY Welding Engineer may require further parameters to be shown on the WPS. 8.1.3

Pipe and Fitting Materials 86B

Pipe, valves, flanges, and fittings from different manufacturers, or manufactured from materials supplied from different sources or in different supply conditions, require separate procedure qualification as detailed in 8.2.2 & 8.2.3, unless a material grouping is approved by the COMPANY. 8.1.4

Welding Procedure Parameters 87B

During weld procedure qualification, all relevant procedure data, irrespective of whether the item is a listed essential variable, shall be captured and recorded. Sufficient information shall be recorded to allow full replication of the procedure qualification welds. A record of the data shall be kept for the purpose of aiding production and to assist with the diagnosis of problems, but need not be formally entered on to the PQR, e.g. GMAW/PGMAW machine ‘slope-in’ settings. The methods of measuring the welding parameters and the records to be kept shall be agreed with the COMPANY Welding Engineer. Following WPQT, the pWPS shall be revised to reflect the parameters recorded during qualification. For each welding pass the values for current, voltage and travels speed shall be recorded on the WPS by either: 

Within the range recorded during WPQT, noting that transient and anomalous values should not be used to establish the parameter range;



The mean value 10%.

The final WPS shall state parameters for each pass. However, if fill passes (i.e. passes other than root, hot pass and cap) have similar values, the parameters may be combined on the WPS. When a welding consumable or group of consumables is qualified to weld several different components or pipe sizes, every effort should be made to ensure that the parameters specified on the individual WPSs are common across the group of WPSs. A WPS written with more than one supporting Procedure Qualification Record (PQR) shall not permit optional processes, but shall specify the process for each pass.

Page 33 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) All welding procedures, including repair procedures, shall be qualified by visual examination, NDT and mechanical testing as detailed in BS 4515-1 and this specification. The final WPS shall be accepted by the COMPANY before being used for production welding. 8.1.5

Arc Energy 8B

The arc energy for each pass shall be calculated using the recorded values of current, voltage and travels speed from the PQR without the addition of a percentage. Arc energy shall be recorded for each pass on the PQR. For multiple (electrically isolated) tandem electrode welding processes e.g. SAW or PGMAW, the effective arc energy per pass shall be calculated as the sum of individual arc energies for each electrode. For pulsed procedures, the effective arc energy shall be calculated on the basis of RMS values. Voltage and current shall be determined with calibrated meters and recorded for each pass during WPQT welding using a suitable COMPANY approved monitoring equipment. Note: Calculation of arc energy assumes each welding process has an efficiency of 1. U

8.1.6

U

Records 89B

The details of each weld procedure shall be recorded. Forms used to record WPS and WPQT details shall contain the relevant information. The format shall be subject to approval by COMPANY. The PQR documentation package for each WPS shall comprise: 

As-run records.



NDT results.



Mechanical test results and macrographs.



Consumable certification.



Parent material certification.

The following data shall also be available if requested by the COMPANY Welding Engineer: 

Calibration certificates for equipment and measuring devices.



SNT (ASNT) Written Practice (if applicable).

Page 34 of 75



Welding Inspector and NDT personnel certification.



NDT procedure qualification records.



Testhouse approval certification.

The approved WPSs and PQR packages shall also be available in a good quality electronic format. Period of Validity

8.1.7 90B

For new pipeline construction projects, new WPSs shall be prepared and qualified. For the purposes of undertaking further work to an existing pipeline, a WPS may remain valid indefinitely. The COMPANY Welding Engineer shall be consulted before re-using the WPS. Changes Affecting Qualification and Approval (Essential Variables) of butt welds

8.2 37B

Modified to Read: U

The following restrictions apply to all welding procedure specifications in addition to those given in BS EN 288-9 and BS 4515-1.

Page 35 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) Table 1 U

WELDING PROCEDURE SPECIFICATION DETAILS AND CHANGES AFFECTING APPROVAL U

ELECTRODE a OR FILLER MATERIALS Welding b1 parameters b2

b3i b3ii

b4

b5

Preheat and p4 Interpass Temperature Add:

TRADE NAME

ANY CHANGE

Electrical stick-out Any change exceeding ±5mm (SAW, GMAW/PGMAW, GSFCAW) Arc voltage Any change outside the range of the approved production WPS Wire feed speed Any change outside the range qualified Welding current Any change outside the range of the approved production WPS Travel speed Any change outside the range of the approved production WPS Calculated value of arc Any change outside the range energy of the approved production WPS Application of preheat Any change.

U

8.2.1

Transfer of WPSs 91B

Welding procedures shall not be transferred from one CONTRACTOR or SUBCONTRACTOR to another without re-qualification. Material Supply Condition

8.2.2 92B

Changes in the following material condition shall require re-qualification of the WPS:

8.2.3



Steel making, plate rolling, forging, or pipe manufacturing process.



Manufacturing facility for strip, billet, plate, pipe, or forging.

Chemical Composition 93B

The following shall constitute essential variables: 

For sour service pipelines, a change of composition resulting in a change of greater than +0.00 or -0.03 CEIIW or greater than +0.01 or -0.02 Pcm.

Page 36 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) CEIIW and Pcm are defined as follows:

CE IIW  C 

Pcm  C 

Mn Cr  Mo  V Ni  Cu   6 5 15

Si Mn  Cu  Cr Ni Mo V      5B 30 20 60 15 10

Diameter

8.2.4 94B

The pipe diameter shall be within the limits shown in Table 8.1. Table 8.1 U

DIAMETER RANGE OF APPROVAL FOR WPQT U

TEST PIPE DIAMETER (mm)

RANGE OF APPROVAL (mm)

<60.3

<60.3

60.3 < D < 323.9

60.3 to 323.9

323.9 < D < 610

323.9 to 610

D >610

>610

Weld Preparation

8.2.5 95B

For narrow gap welding, any change in bevel angle beyond ±1°, root face beyond ±50%, or root gap +0.5 mm, constitutes an essential variable. Any weld preparation with an included angle of less than 20° shall be considered to be narrow gap welding. For all other welding, any changes in bevel angle by more than ±5°, or variation in root gap/root face by more than ±50%, constitutes an essential variable. 8.2.6

Type of Joint 96B

Use or deletion of temporary, e.g. copper, backing rings or shoes shall be considered an essential variable. Change from a girth weld to a fillet weld shall constitute an essential variable. Fillet welds shall be qualified separately. The configuration, shape, and size of branch weld test pieces shall be the same as the branch welds to be made in production. The qualification of branch welds shall include an additional butt weld qualification to prove the mechanical properties of the joint. Page 37 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) 8.2.7

Filler Metal 97B

The following changes shall require re-approval of the WPS: 

Any change in filler metal designation, filler metal manufacturer, manufacturing location, or brand name.



Any change in consumable diameter per pass.



A change in batch number if consumable batch control has been specified (see 7.2.2).

Welding Machines

8.2.8 98B

The welding unit, power supply type, manufacturer, model number and software version number shall constitute essential variables for semi-automatic, mechanised and automatic welding. 8.2.9

Type of Current 9B

For pulsed welding, the type of current includes the pulse rate, pulse shape and maximum and minimum current. 8.2.10 Preheat Temperature 10B

The method of preheat application shall be an essential variable. 8.2.11 Interpass Temperature 10B

The use of rapid cooling of welds constitutes an essential variable unless simulated in WPQT. 8.2.12 Time Interval 102B

For hydrogen controlled processes, an increase in the maximum time between completion of the root pass and the start of the second pass shall not exceed the time lapse recorded during the welding of the test piece. 8.2.13 Other Parameters 103B

Changes to the following require re-qualification of the WPS: 

Head angle, electrode spacing from top dead centre and direction of rotation for 1G rotated welding.



Electrode spacing for welding procedures utilizing multiple electrodes e.g. tandem wire SAW, or mechanized tandem wire or twin torch processes.

Page 38 of 75



Destructive Testing 38B

Add: U

The blanks from which the mechanical test pieces are machined may be cut from the qualification weld using oxy-fuel gas cutting; but its dimensions shall be sufficient to allow the material of the final machined test piece to remain unaffected by the heat from the cutting operation. Test specimens shall not be subjected to any elevated temperature degassing treatment. The type and extent of mechanical testing shall be in accordance with Table 8.2. The test piece locations shall be as shown in Figures 8.1 and 8.2.

Page 39 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) Table 8.2 U

INSPECTION AND TESTING OF THE TEST PIECES FOR GIRTH WELDING U

TYPE OF INSPECTION/TEST Transverse Tensile Test

FULL PENETRATION REPAIR

BUTT WELD 2 (diameters ≤ 323.9mm)

2

4 (diameters > 323.9mm) 1a

1h

Impact Test

4b,c,d

2b,c,d

Side Bends

2e

2e

Macro-examination and hardness test

3f,g,h

1h

CTOD

3h,i

3h,i

All Weld Tensile Test

NOTES: a.

When an ECA is used to determine defect acceptance levels, a minimum of three all weld metal specimens shall be taken.

b.

Additional sets of Charpy Impacts may be required by the COMPANY Welding Engineer. For example, if very thick pipe is to be utilised or the combination of processes or consumables has not been adequately sampled by the specified locations.

c.

For thicknesses greater than 20 mm, a total of 6 sets shall be required. The additional 2 sets shall be taken from the outer surface (see Figure 3 BS 288-9).

d.

Impact testing is not required for pipe sizes below 60.3 mm diameter with thicknesses less than 12.7 mm.

e.

Side bends are only required for GMAW/PGMAW and GSFCAW (Vertically down) welding processes. For Wt >25mm four side bends shall be conducted. For full and partial penetration repairs two side bends are required.

f.

Additional macro-examinations and hardness tests are required for long seam T-intersections (see 8.3.3).

g.

For non-sour pipelines, the number of hardness surveys may be reduced (see 8.3.4).

h.

CTOD tests shall comprise a minimum of one set of weld metal and two sets of fusion line samples.

i.

Tests are only required for pipelines with ECA based acceptance criteria or if required by the pipeline designer.

j.

See 7.1.1 for weld chemical analysis test requirements.

Page 40 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) Figure 8.1 U

LOCATION OF TEST SPECIMENS FOR A FIXED POSITION GIRTH WELD PIPE FOR U

UPWARDS WELDING

6

Key: 1 Area 1 for:

7 1

5

8

2

3 4

- 1 tensile specimen 2 Area 2 for: - Impact test specimens (WCL, FL & FL+2mm) - 1 macro test specimen - Additional test specimens if required. 3 Area 3 for: - 1 tensile specimen 4 Area 4 for: - 1 macro test specimen - 1 hardness test specimen 5 Area 5 for: - AWT Specimens 6 Top for fixed pipe 7 Area 7 for: - 1 macro test specimen - 1 transverse tensile (>323.9mm) - Impact test specimens (WCL, FL & FL +2mm) 8 Area 8 for: - 1 transverse tensile (>323.9mm)

Figure 8.2 U

LOCATION OF TEST SPECIMENS FOR A FIXED POSITION GIRTH WELD PIPE FOR U

DOWNWARDS WELDING 6 7 1

2

5

3 4

Page 41 of 75

Key: 1 Area 1 for: - 1 tensile specimen 2 Area 2 for: - 1 macro test specimen - 1 hardness test specimen - Side bends 3 Area 3 for: - 1 tensile specimen 4 Area 4 for: - Impact test specimens (WCL, FL & FL+2mm) - 1 macro test specimen - Additional test specimens if required. 5 Area 5 for: - AWT Specimens - 1 transverse tensile (>323.9mm) 6 Top for fixed pipe 7 Area 7 for: - 1 macro test specimen - 1 transverse tensile (>323.9mm) - Impact test specimens (WCL, FL & FL+2mm)


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) CTOD and additional all weld tensile specimens may be taken from available material around the weld. The locations shall be agreed with COMPANY. More than one weld may be required to provide sufficient material for testing. Transverse Weld Tensile Test

8.3.1 104B

Add: U

The results of all transverse weld tensile tests shall meet or exceed the specified requirements for the pipe (base metal) with respect to specified tensile strength. Transverse weld tensile specimens shall fail at a location within the HAZ or base metal. Failure in the weld metal is unacceptable. If base metals of different strength levels are used, then acceptance criteria shall be based on the lower strength base metal. 8.3.2

Weld Metal Tensile Testing 105B

Add: U

The weld metal shall exceed the parent pipe SMYS by between 80 to 200MPa. Weld metals exhibiting overmatching shall ensure this is not to the detriment of other mechanical properties and shall be demonstrated through WPQT. Any large deterioration of properties compared shall be cause for investigation by the CONTRACTOR and COMPANY Welding Engineers. Weld metal overmatching shall be achieved at both room temperature and maximum design temperature. The weld metal strength shall be considered in relation to the actual pipe yield strengths when an ECA is used. Macro-Examination

8.3.3 106B

Add: U

Three macro-examination test pieces shall be taken from each WPQ. The locations shall be at 12, 3 and 6 o’clock (see Figures 8.1 and 8.2). When girth welding SAW-welded linepipe, an additional macro-examination specimen shall be extracted from the girth-weld at the T-intersection region between the girth weld and seam weld. All macro-examination specimens shall be polished to a metallographic (1m) finish and etched in a 2-10% Nital solution, or other suitable COMPANY accepted etchant. The etched specimens shall be thoroughly examined at 10 times magnification.

Page 42 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) The prepared surface shall exhibit no cracks or lack of fusion defects. Volumetric defects shall be investigated and shall not exceed the acceptance criteria of Section 13.0. Original photo-macrographs of macro-examination specimens at approximately 3 to 5 times magnification shall be included in the PQR documentation. 8.3.4

Hardness Testing 107B

Clarification: U

All hardness testing shall meet the sour-service criteria as laid down in BS EN 288:9, Table 3. The parent material hardness shall not exceed the values permitted in the relevant linepipe material specification. Add: U

Hardness testing shall be in accordance with EN 1043-1 or ISO 6507-1. The hardness surveys shall be undertaken on each of the macro-examination specimens specified in 8.3.3. Each survey shall consist of three rows of indents. One traverse shall be located below the cap, one above the root (or internal surface) and one at mid-thickness. The positions are shown in Figure 8.3. The mid-thickness traverse may be waived for single sided welds below 12.7 mm. The COMPANY Welding Engineer may require additional hardness indent positions, e.g. when a consumable type has not been sampled by the three specified traverses. Figure 8.3 U

GIRTH WELD HARDNESS INDENTATIONS U

1 - 2mm t/2

1 - 2mm

NOTES: 1. Parent material indentations shall be at least 20 mm from the fusion line. 2. The first HAZ indentation shall be placed as close to the fusion line as possible. Further indentations into the HAZ shall be separated by approximately 0.5 mm, however the minimum

Page 43 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) centre-to-centre separation requirement of 3 times the mean diagonal of the nearest indentation shall be maintained (ref. ISO 6507-1). 3. The same survey pattern shall be applied to double-sided welds.

The macrophotographs shall show the position of each hardness indent and shall be included in the PQR along with tabulation or diagram showing the result and location of each indent. The maximum and minimum values shall be identified. Impact Testing

8.3.5 108B

Clarification: U

For gas pipelines the impact test temperature shall be no higher than minus 10°C. Clarification: U

Sample preparation shall be conducted in accordance with BS EN 10045 Part 1. Add: U

Impact tests shall be carried out in the fusion line + 2mm locations. The impact test requirement for all pipe/bend/fitting/forging is 50J minimum average and 40J minimum individual, for 3 specimens at the minimum design temperature. Add: U

8.3.6

Crack Tip Opening Displacement (CTOD) Testing 109B

Fracture toughness tests are only required for pipeline subject to an ECA, and shall be conducted at minimum design temperature. The required minimum CTOD value shall be 0.15 mm unless otherwise justified through an ECA. CTOD testing shall be undertaken in accordance with BS 7448 Parts 1 & 2 by a testing laboratory specifically approved for CTOD testing by COMPANY. Testing shall be based on the use of through thickness notched, single edge notched bend (SENB) specimens (BS 7448 Part 1 paragraph 5.1) in the NP orientation, unless agreed otherwise by COMPANY. Test specimens shall be notched and fatigue cracked to sample the microstructures at the weld centre line and in the coarse grained HAZ adjacent to the fusion line. The number of valid test results employed to determine the characteristic CTOD of the weld metal and HAZ microstructures shall comply with BS 7910 paragraphs K.2.3 and 7.1.5.5. This may require a greater number of CTOD specimens than listed in Table 8.2.

Page 44 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) Post test metallography shall be used to identify the initiation point and the associated microstructure on a minimum of three HAZ specimens selected by COMPANY.

The

initiation point of brittle events shall be identified by metallography. The specimen is considered qualified if: 

The pre-crack tip is not more than 0.5mm from the fusion line.



Grain coarsened HAZ microstructure is present within a region confined by a plane perpendicular to the crack plane through the crack tip and a parallel plane 0.5mm ahead of the crack tip.

8.3.7

Bend Testing 10B

Transverse root bend and side bend specimens shall be prepared and tested in accordance with ISO 5173: 

Specimens shall be of full material thickness and the root samples shall be nominally 25mm in width while the side bend specimens shall be nominally 10mm in thickness.



Bending shall employ a former having a minimum diameter of 4x and a maximum diameter of 6x the full pipe wall thickness.



Testing shall not reveal any open weld defects greater than 3mm in length.



Defects shall not be acceptable in the root or hot pass location.

Tearing from the specimen edges up to a maximum length of 3mm shall be acceptable provided that it is not associated with any weld defects.

Page 45 of 75



TESTING, QUALIFICATION AND APPLICATION OF WELDING PROCEDURE FOR 8B

FILLET WELDING 9.1

Non-Destructive Testing of Fillet Welds 39B

Clarification: There are no additional NDT requirements to visual and MPE for fillet welds. U

U

Destructive Testing of Fillet Welds

9.2 40B

Add: U

If mechanical properties are relevant to the application, an additional qualification shall be made, e.g. a butt weld.

Page 46 of 75



TESTING, QUALIFICATION AND APPROVAL OF WELDERS

10.1

9B

General 41B

Add: U

Welders shall be qualified prior to welding on the pipeline. Previous welder qualification tests may be accepted by the COMPANY provided they are fully documented, supported by production records demonstrating satisfactory welder performance, and are less than 6 months old. These tests shall have been conducted utilizing a WPS substantially the same as that for the current work and for automatic, mechanised or semi-automatic welding procedures, utilizing the same type, manufacturer and model number of welding unit and power supply. Additionally, these tests shall have been conducted by the same fabrication CONTRACTOR and witnessed by the COMPANY, or have been conducted by a COMPANY accepted independent testing laboratory. In addition to the practical welding test and prior to the commencement of production welding, all welders shall be required to attend a briefing session arranged jointly by the CONTRACTORS and the COMPANY welding engineer. This briefing will detail the elements of good welding practice and the specification requirements applicable to production welding. These requirements shall be further emphasized during regular toolbox sessions and each welder shall also be issued with a card or booklet summarizing these requirements, the contents of which shall be agreed between the CONTRACTOR and the COMPANY. Any welder who, in the opinion of the COMPANY is either consistently ignoring good welding practice or specification requirements or is responsible for a high level of repairs during production shall be removed from the work, and shall undergo a re-training programme accepted by the COMPANY before a retest may be considered. Butt Joints

10.2 42B

Add: U

Welder qualification tests shall be carried out on full diameter project pipe nipples. Test welds shall be visually sealed at each end until at least the root bead and hot pass have been completed around the full circumference. All qualification welding shall be carried out in the presence of a COMPANY representative. The COMPANY’s decision on acceptance is final. Welders shall weld at least 50% of the circumference of the test pipe.

Page 47 of 75



Fillet Welds for Sleeves, Sockets, Slip-on Flanges or Other Attachments 43B

Clarification: U

The simulation of a fillet weld joint using flat plate welds shall not be permitted. Add: U

Procedures for welding and NDT of fillet welded attachments to pipelines shall be subject to acceptance by the COMPANY. The pipe area surrounding a fillet weld shall be tested for laminations using MUT up to a distance of 100 mm surrounding the projected locations of the weld toes. Any laminations found shall comply with the applicable project line pipe specification. Where any fillet welds are to be made using multiple passes, the first pass shall be deposited mainly on the pipe and the final weld pass shall not touch the pipe. Completed fillet welds shall be examined by visual examination and MPE. 10.5

Changes Affecting Qualification and Acceptance (Essential Variables) of Welders 4B

Modified to Read: U

For manual metal-arc welding, a change in electrode trade name. 10.6

Non-Destructive Testing 45B

Add: U

NDT of welder test-pieces for butt welds shall include visual examination, MPE. RE and MUT/AUT if GMAW/PGMAW and GSFCAW (Vertical down) is used.

Where SMAW,

GTAW or SAW or GSFCAW (Vertical Up) is used visual examination, MPE, and RE shall be used. If the application of AUT for the inspection of pipeline girth welds has been agreed by COMPANY, it may be used for the assessment of the welder qualification welds in place of radiography. However, the acceptance criterion used shall be BS 4515-1 Table 6 and section 13.1.2 of this specification, rather than an ECA based criterion. Destructive Testing

10.7 46B

10.7.2 Butt joints 1B

Add: U

Page 48 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) For butt welds, macro-examination shall be undertaken. Additionally, for welding using GMAW/PGMAW and GSFCAW (Vertical Down) welding processes, bend testing in accordance with ISO 5173 shall also be performed.

Page 49 of 75



PRODUCTION WELDING 10B

Add: U

Any weld suspected of not having been produced in accordance with the accepted welding procedure shall be cut out, and may be subject to investigation at the discretion of the COMPANY. 11.1

Proximity of Welds 47B

Add: U

The distance between pipeline girth welds shall not be less than twice the outside diameter of the pipe. The distance between pipeline girth and branch/attachment welds shall not be less than one pipe diameter. The distance between branch/attachment welds on the pipeline shall not be less than one pipe diameter. 11.2

Pipe End Preparation 48B

Add: U

Pipe ends shall be bevelled to the dimensions specified in the WPS. Weld bevels shall be prepared by machining with a floating head cutter. The bevelling machine shall follow the ID surface contour in order to ensure a consistent root face dimension. Mechanised thermal cutting may be accepted for tie-in welds. The cut surface shall be ground back nominally 2mm. Manual cutting of field bevels is not permitted. Any protective coating on the end bevel shall be removed prior to welding by a COMPANY accepted method. Weld repairs to pipe ends shall not be permitted.

The COMPANY may permit minor

imperfections in the pipe ends to be repaired by grinding, prior to assembly for welding, provided the remaining wall thickness is acceptable as confirmed by MUT. If AUT is to be used, a reference line at a specified distance from the root face shall be scribed onto the pipe surface to allow the exact location of the root bead to be identified. Clarification: U

On pipe which is to be cut back, a zone extending 100 mm from the proposed position of the new field bevel shall be examined by VE, and MUT to check for laminations to the requirements of the appropriate linepipe material specification. Page 50 of 75



Fusion Faces 49B

Add: U

Surfaces contaminated with oil or grease shall be cleaned utilizing solvent. Degreasing of base metal shall extend at least 50 mm from the edge of the fusion faces on both ID and OD surfaces. All cleaning solvents shall be used from a suitable container, shall have all necessary documentation available and be accepted by the COMPANY as HSE compliant. Alignment

11.4 50B

Modified to Read: U

Pipes shall be aligned with care. The alignment of abutting pipe ends shall minimize the internal offset between surfaces. Any offset greater than 1.5 mm, provided it is caused by dimensional variations within specified tolerances, shall be equally distributed around the circumference of the pipe or fittings. Misalignment shall be reduced to a minimum by rotation of the pipes to obtain the best fit. Maximum misalignment shall be: 

< 1.0 mm for pipe diameter < 6”.



1.5 mm for pipe diameter ≥ 6”.

Add: U

Heat shall not be used to correct excessive misalignment. Internal tapering shall not be permitted if the tapering interferes with ultrasonic inspection. 11.5

Line-Up Clamps and Pipe Supports 51B

11.5.1 Use of Line-Up Clamps 12B

Modified to Read: U

Powered internal alignment clamps shall be used for pipe-to-pipe butt welds. Where access does not permit the use of an internal clamp for pipe-to-pipe welds, an external clamp shall be used. For small diameters (<150 mm), the use of an external clamp may be proposed for COMPANY acceptance. A welding sequence that distributes the stresses as evenly as possible shall be used, e.g. two welders working diametrically opposite each other. If an internal line-up clamp is used, the root run shall be 100% complete before the clamp is removed. When an external line-up clamp is used, the root run shall be at least 50% complete before the clamp is removed.

Page 51 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) Line-up clamps or other devices for maintaining line-up shall be of the same type as used during the welding of test pieces for WPS approval. The stage at which line-up clamps are removed shall be stated in the WPS and qualified subject to the approval of the COMPANY. The line-up clamp shall be designed to prevent damage to the pipe and coatings. Straps, brackets, cleats, or similar plate sections shall not be attached to the pipe by welding for the purposes of alignment. Modified to Read: U

Internal line-up clamps shall not be removed until the completion of the root and hot pass. Alternatively the CONTRACTOR shall present a case, supported by stress analysis, which proves that a weld with only the root pass in place will not be adversely affected by movement. If an internal clamp incorporates a copper back-up bar, the backing bar shall be subject to a full circumferential visual examination at least once every ten welds to ensure no fusion of copper is taking place. Add: U

The COMPANY shall accept line-up methods for fittings and flanges. Tack Welds

11.6 52B

Add: U

All tack welds (if used) shall be deposited by qualified welders using low hydrogen welding in accordance with an accepted welding specification. Where preheat is specified, it shall be applied prior to tack welding and be effective over a distance equal to three times the wall thickness or 75 mm whichever is the greatest and shall be maintained until the joint is complete. Alignment by tacking for fabrication welds, e.g. for pipe to flange joints, shall be subject to the acceptance of the COMPANY. The following shall apply when tacking is used: 

The joints to be tacked will be adequately supported.



Tack welding to be undertaken by qualified welders in accordance with Section 10.0.



The preheat level required for the main WPS shall be applied for tacking and shall be not less than 50°C.

Page 52 of 75



The preferred method is bullet tacking. The bullets shall be made from compatible linepipe material.



A minimum of four tacks shall be used for diameters >100mm. More tacks may be required for diameters > 300mm.



All welding shall be confined to the weld preparation and not impinge on the root area.



Tacks shall be removed by grinding as root welding progresses around the butt.



If tack welds are to be incorporated in to the final weld, they shall be at least 25mm long and shall be thoroughly cleaned of slag and taper ground at each end to ensure complete root continuity.



The intended method of tacking to be used in production shall be incorporated in the WPQT.

COMPANY may agree to waive MPE of the ground area following tack removal. Stray Arcs

11.8 53B

Add: U

The COMPANY shall have the option to require removal of weldments with more than one arc burn from the pipeline. Repair of parent material by welding is not permitted. If blending to remove the effects of arc burns reduces the wall thickness below the specified minimum, the defective pipe section shall be cut out and the pipe re-bevelled and re-welded. Welding shall not be used to repair arc burns. For non-reeled applications, if a nipple is used to replace the defective section, its length shall be at least two pipe diameters. Welding return cables shall be of sufficient cross-sectional area to prevent concentration of current and shall be securely attached to prevent stray arcing. Attachment by welding shall not be performed. Clarification: U

Areas showing stray arcs may only be repaired by mechanical removal of the defective material and blending of the excavation. MPE together with confirmation that pipe or fitting wall thickness is within specified tolerances shall be confirmed.

Page 53 of 75



Weather Conditions 54B

Add: U

When necessary, measures shall be taken, e.g. by covering the pipe ends, to prevent water or other extraneous matter being channelled into the weld region. The COMPANY shall decide if the protection given from the weather is adequate and that it will not affect the quality of the completed weld. 11.10 Preheating and Post Weld Heat Treatment 5B

General

11.10.1 13B

Modified to Read: U

Preheat and interpass temperatures shall be in accordance with the COMPANY approved WPS. As a minimum the preheat temperature shall be selected to ensure that: 

The pipe is dry prior to welding



The metal temperature is greater than 30°C, or greater than 50°C when moisture is present on the pipe, or when the ambient temperature is below 5°C.



The hardness requirement of Section 8.3.4 is met for the weld and HAZ.

If the weld is to be cooled rapidly to allow immediate AUT, this shall be simulated during WPQT.

Assisted cooling shall not commence until the weld temperature has cooled

without interference to below 300°C. 11.10.2

Preheating 14B

Add: U

Preheating shall be applied by gas or electrical equipment. Induction heating is preferred for pipeline welding and is mandatory for welding of pipe diameters greater than 500mm. Hand held gas torches shall not be used for welding when preheats greater than 80°C are required. Welding or cutting torches shall not be used for preheating purposes. The preheating equipment shall maintain a satisfactory temperature distribution and shall not interfere with the welding operation. Care shall be taken to avoid damage to any coatings and interference with the welding.

Page 54 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) Preheating shall be applied uniformly on both sides of the joint preparation around the entire periphery. Local preheating may be used for repair welding. Correct preheat temperatures shall be maintained throughout the welding of the joint. The preheat temperature shall be measured at a minimum distance of 75 mm from each edge of the weld bevel at a minimum of four circumferential locations, each approximately 90° apart. Preheat temperature measurement shall be made on the heated face of the pipe after a time interval following the removal of the heat source to allow for temperature equalisation. The time interval shall be 1 minute per 12.7 mm of wall thickness, e.g. 2 minutes for 25 mm thick material. The preheat temperature shall be confirmed immediately prior to the commencement of welding and around the whole joint whilst welding is taking place. Interpass temperature shall be measured on the parent material at the edge of the weld bevel near the weld start location. The temperature shall be measured immediately before the passage of the arc and the maximum specified interpass temperature shall not be exceeded. For continuous rotated welding, interpass temperature shall be measured at least once per complete revolution. Temperature indicating crayons which melt on attaining the specific temperature may be used to check preheat and interpass temperature, but shall not be marked on weld bevels, weld beads or surfaces to be welded. Temperature indicating crayons or paints which indicate temperature by colour change shall not be used. Alternatively, suitably attached (and calibrated) thermocouples, or calibrated contact or optical pyrometers, may be used to check preheat and interpass temperatures. When pipe-to-pipe joints are to be left partly completed, the joint shall be wrapped in dry insulating, heat-resisting material with a waterproof backing and shall be cooled at a slow uniform rate. Preheat shall be re-applied and the specified temperature attained before recommencement of welding. 11.10.4

Thermocouple Attachment and Junctions 15B

Add: U

Thermocouples shall be attached to the pipe by the capacitance discharge method. After use, the thermocouples junctions shall be removed by grinding and the area of attachment shall be examined by MPE.

Page 55 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) 11.11 Branches 56B

Add: U

Procedures for cutting, joint preparation, setting-up, welding and NDT shall be subject to COMPANY acceptance. Forged fittings shall be used for branches and other pressure containing attachments unless otherwise accepted by the COMPANY. 11.11.2

Spacing of Branches 16B

Add: U

Refer to 11.1 11.11.4

Welding 17B

Add: U

11.11.4.3 Set-in Fitting Welds Set-in fitting welds shall be inspected as follows: 

Where accessible and following completion of the full weld, the root bead shall be ground flush on the inside of the pipe, its location clearly marked with indelible pen and inspected by visual and MPE.



Weld caps to be subjected to visual and MPE;



The full welds shall be examined with radiography using the SWE/SWV technique with the film inside and radiation source outside, using a minimum source to film distance of 600mm. A minimum of four equidistantly spaced separate exposures shall be used for branches 150mm nominal bore. The DWE/SWV technique may only be used if accepted by the COMPANY. In each event the centre radiation beam shall pass through each weld region being tested at normal incidence to the weld face.

Set on fitting welds shall be inspected as follows: 

The root bead and weld cap shall be examined by visual examination. Visual examination of the root bore shall be undertaken through the bore of the fitting from the outside of the pipe;



Weld caps shall be examined by MPE. Where access allows MUT shall be undertaken from the inside surface of the fitting.

Page 56 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) 11.12 Inter-run Cleaning 57B

Add: U

Contact tips shall not be fused into the weld metal. A visual inspection shall be undertaken between weld passes to confirm no copper has been deposited. 11.13 Partially Completed Joints 58B

Add: U

Offshore pipeline welds or welds on fittings, tie-in welds, or repairs shall not be allowed to cool below the specified minimum preheat temperature before weld completion. No welds shall be allowed to cool below preheat temperature before the completion four full circumferential passes. All welds shall be completed by continuous welding. 11.14 Fillet Weld Attachments 59B

Procedures for welding and NDT of fillet welded attachments to pipelines shall be subject to approval by COMPANY. The pipe area surrounding a fillet weld shall be tested for laminations using UT up to a distance of 100 mm surrounding the projected locations of the weld toes. Any laminations found (individual or cluster) shall not exceed a total area of 500 mm2. No lamination regardless of size shall be permitted within 25 mm of the projected weld toes. If any fillet welds are to be made using multiple passes, the first pass shall be deposited mainly on the pipe and the final weld pass shall not touch the pipe. Completed fillet welds shall be examined by VE and MPE. 11.15 Records 60B

Add: U

All documentation required by this specification and BS 4515-1 shall be collated, indexed, stored safely and presented to the COMPANY. A log identifying, by number, each pipe or fitting and identifying the weld numbers joining them to other items shall be compiled. Each circumferential weld (whether a field joint or shop-made weld) shall be allocated a unique number, which shall be used for reference to the weld in all reports, radiographs and test documents. Quality records shall include the following:

Page 57 of 75



Record of contract/design review.



Material certificates.



Consumable certificates.



Welder name and / or number.



WPS’s.



Welding procedure acceptance test records.



Welder or welder operator acceptance certificates.



Non-destructive testing personnel certificates.



Heat treatment records.



Non-destructive testing and destructive testing procedures and reports.



Dimensional reports.



Records of repair and other non-conformity reports.



Site or technical queries pertaining to welding and NDT.

The above documentation shall be traceable back to individual weld numbers, where applicable. The accepted WPS and PQR packages shall also be available in a good quality electronic format.

Page 58 of 75



INSPECTION AND TESTING OF WELDS 1B

12.1

General 61B

Clarification: U

Every pipeline weld shall be subject to individual examination and non-destructive test using reliable, modern, and proven techniques, and shall be shown to meet the design code acceptance criteria in all respects before the pipeline is put into service. An ECA and CTOD tests are mandatory when pipeline installation is by reeling or S-Lay. For the fabrication of spools CTOD’S and ECA is only required where the minimum design temperature is lower than -46°C and or thicknesses > 40mm. The use of an ECA shall not be required on pipe diameters ≤6” and/or wt <10mm. The use of narrow gap welding techniques (with an inclusive bevel angle  20°) dictates that AUT shall be required. Each production butt weld shall be subjected to a visual (external), RT and supplementary UT or AUT examination or a combination of both, unless otherwise agreed with the COMPANY. For wall thickness above 25 mm, AUT is the preferred NDT technique. For manual or semi-automatic welding processes using a conventional bevel configuration, one of the following NDT methodologies may be adopted subject to COMPANY review and approval: 

Where RT is the primary NDE method, MUT shall be used to supplement RT when planar defects are detected during production welding. MUT shall be used to establish defect size, height and position. An ECA (when required) shall be used to develop the weld NDE acceptance standard taking cognizance of the NDE sizing accuracy.



Alternatively, visual and RT may be considered, provided the CONTRACTOR can demonstrate its ability detect the defects defined within the workmanship acceptance criteria as detailed in this specification and Table 5 (BS 4515-2) and Section 13.1.2 of this specification. The acceptance criteria shall be no cracks or planar defects within the weld i.e surface breaking or within the body of the weld. RT and single wall techniques shall only be used for NDE of girth welds. To avoid repairs or cut-outs it is recommended that a MUT be qualified to assist RT.

Page 59 of 75



Radiographic procedures shall be qualified on test welds containing representative defects which are subjected to sectioning to confirm defect sizes and NDT by additional methods. The CONTRACTOR shall demonstrate that his NDT production methods and procedures can detect the defects defined within the acceptance criteria. Proposed NDT procedures shall be submitted in writing to the COMPANY for approval. All procedures shall be qualified and approved by the COMPANY before use. The full length of pipeline branch and fillet welds shall be examined in accordance with 11.11.4 and 11.14. The use of automatic ultrasonic testing (AUT) shall be subject to approval by the COMPANY.

If the use of AUT has been approved, testing shall be performed in

accordance with GIS 43-339. The use of AUT is not permitted in place of radiography for the following weld types: 

Welds connecting pipes with an internal taper.



Butt welds to valves, flanges and other fittings.

MUT and MPE equipment and personnel shall be available at site for the full duration of pipeline construction. The COMPANY shall have the right to inspect or test any weld by non-destructive or destructive means. This inspection may be made during the welding or after the weld has been completed.

The right of inspection may include NDT undertaken by COMPANY

personnel in addition to any NDT undertaken by the CONTRACTOR. For example, the COMPANY may choose to inspect welds by MUT. On a pipe-laying barge, the weld shall not be moved past the weld repair station until the interpretation of the radiograph and all other NDT is complete and the weld has been judged satisfactory. Coating/ wrapping of a welded joint shall not begin until the weld has been judged satisfactory, unless otherwise approved by COMPANY. Clarification: U

Completed welds may be ground when agreed with the COMPANY to facilitate NDT provided the wall thickness complies with the minimum specified limit. Grinding shall ensure no stress raisers and a smooth transition exists.

Page 60 of 75



Personnel Qualification 62B

Modified to Read: U

NDT personnel shall hold current Level 2 certification (or equivalent), specific to weld testing, for the appropriate NDT methods to any of the following standards as a minimum: 

CSWIP (TWI, UK);



BGAS-CSWIP (TWI, UK);



PCN (BINDT, UK);



ACCP (ASNT);



SNT-TC-1A (ASNT).

NDT personnel certificated to the requirements of a Written Practice under the rules of SNT-TC-1A shall not be used, unless the Written Practice and the personnel certification has been reviewed and accepted by COMPANY for the specific work. Personnel engaged in AUT shall be qualified in accordance with GIS 43-339. Radiographic Testing

12.4 63B

12.4.1 General 18B

Add: U

Radiographic testing shall be conducted using X-ray equipment. Where the use of X-ray equipment is impracticable, Iridium 192, Ytterbium 169 or Selenium 75 may be used subject to acceptance by COMPANY. Other sources of gamma rays are not permitted. Radiographic practice shall be in accordance with this specification and ISO 17636. 12.4.2 Approved Radiographic Procedures 19B

Add: U

12.4.2.1 General As part of the radiographic procedure qualification, test radiographs shall be produced using each radiographic procedure planned for use; these shall be made on the welding procedure qualification welds or welds made with the production WPS. The full circumference of each test weld shall be radiographed. Film type shall be ISO 11699-1 Class T2 or ASTM E1815-96 Class I, e.g., Agfa Structurix D5 or Kodak Industrex T200, or finer grain (slower) film. Where it is shown that exposure

Page 61 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) times would exceed 2 minutes using X-ray equipment with this film, the use of ISO 11699-1 Class T3 or ASTM E1815-96 Class II may be permitted at the discretion of COMPANY. Lead (Pb) intensifying screens shall be used.

COMPANY may accept the use of

fluorometallic screens, as an alternative, where the CONTRACTOR is able to demonstrate that test procedures and results are of a standard acceptable to COMPANY. 12.4.2.2 Procedure Specification (Addition) Specifications of radiographic procedures shall, where relevant, define the following: 

Pipe diameter and wall thickness;



Radiation and source;



X-ray equipment manufacturer, model name and number;



Technique (equipment rating, in voltage, external or internal equipment);



Geometric relationships (source focal-size, film focus distance, object-film distance, radiation angle with respect to weld and film);



Penumbra or geometric unsharpness;



Film type (trade name, designation and dimensions);



Intensifying screens (front and/or back, material thickness, filters);



Exposure

conditions

(voltage,

current

and

duration,

Curie-minutes

and

Gigabecquerel-minutes); 

Processing (developing time/temperature, stop-bath, fixation, washing, drying, manual or automatic processing, manufacturer and type of equipment);



IQI type and sensitivities, in percent of wall thickness, based on source-and film-side indicators, respectively);



Film density;



Film overlap;



Reference to actual WPS;



Temperature of welds during inspection;



Archival life;



Initial source strength.

Page 62 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) 12.4.2.3 Exposure Geometry Source-weld-film arrangements shall comply with ISO 17636 except that the elliptical technique shall be used on all girth welds on pipe ≤88.9mm diameter. The perpendicular technique (straight through) exposures shall not be used unless accepted by the COMPANY. The single wall exposure for single wall viewing (SWE/SWV) technique with the radiation source located inside the pipe/ fitting shall be the preferred technique for radiography of girth welds. 12.4.2.4 Type of Image Quality Indicators Only wire type IQIs (ISO 2504 or COMPANY accepted equivalent) shall be used. 12.4.2.5 Selection of Image Quality Indicators For radiographic procedure qualification, wire type IQIs shall be placed across the weld on both the source side and the film side of the area being examined. The sensitivity level, obtained using the film side IQI, shall be no worse than that given in Table 12.1. The corresponding sensitivity for the source side IQI shall be recorded. If any test radiograph shows one visible wire more on the film side IQI, compared to the source side IQI, the COMPANY has the option to reject the radiographic procedure. Table 12.1 U

SENSITIVITY REQUIREMENTS U

THICKNESS

X RADIOGRAPHY

(1)

GAMMA RADIOGRAPHY

(mm)

SWSI

DWSI

DWDI

SWSI

DWSI

DWDI

4.5-6.0

2.0%

2.5%

3.2%

2.6%

2.7%

3.5%

>6.0-9.0

1.7%

2.0%

3.0%

2.4%

2.5%

3.2%

>9.0-14.0

1.5%

1.8%

Note 3

2.4%

2.5%

Note 3

>14.0-18.5

1.4%

1.7%

N/A

2.0%

2.2%

N/A

>18.5-26.0

1.3%

1.7%

N/A

1.7%

2.0%

N/A

>26.0-40.0

1.1%

1.7%

N/A

1.5%

1.8%

N/A

>40.0

Note 3

Note 3

Note 3

Note 3

Note 3

Note 3

Note 1 - Thickness for SWSI and DWSI is estimated for a single weld thickness Note 2 - Sensitivity shall be no worse than the values given in this table. Sensitivity shall be calculated using the formula:

Page 63 of 75



Thickness of thinnest wire visible in weld area Thickness1 Sensitivity = Note 3 - Sensitivity requirement to be agreed with COMPANY following production of test radiographs. The procedure test radiographs shall be submitted to COMPANY for acceptance prior to the start of production. New procedure test radiographs may be requested at the discretion of the COMPANY whenever any change is made in operating technique or whenever production radiographs differ appreciably from the detail, contrast, definition or density of the qualifying radiographs. Procedure test radiographs shall be readily available for comparison purposes in each darkroom used for radiographic viewing.

Page 64 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) 12.4.2.6 Film Density Except for small localized areas caused by weld weave or discontinuities, the radiographic density shall be between 2.0 and 3.2 in the weld area. If this density range cannot be achieved within the full weld width in a single exposure, then the above density range shall be achieved by producing two radiographs of the weld area at different exposures or by using the sandwich technique, unless otherwise agreed by COMPANY. Densitometers shall be used for measuring density and shall be calibrated using a density strip (density reference scale) of known densities. A density strip certified within the last 3 years to a recognized standard, e.g., NIST or BAM, shall be present on site. To save wear and tear on the calibrated density strip, a working density strip may be used for checking and calibrating densitometers; this shall be checked against the certified density strip at no more than 3 monthly intervals. 12.4.2.7. Information on radiograph The radiographs shall contain the following information: 

Project name, project number, and pipeline identification.



Weld number.



Whether the radiograph is of a repair weld, of a replacement weld or a re-shoot.



Marker(s) indicating the position of the radiograph in relation to the weld.



Pipe diameter and thickness.



Material grade.



Date.



WPS number.

12.4.2.8 Film Viewing Equipment The viewing facilities shall provide subdued lighting of an intensity that will not cause troublesome reflections, shadows or glare on the radiograph. The viewing equipment shall produce sufficient brightness for the illuminated radiograph to be satisfactorily interpreted and shall meet the requirements of ISO 5580. The image shall be free from fog and processing irregularities that could mask the image of actual imperfections. All radiographic film shall be dried thoroughly prior to viewing.

Page 65 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) 12.4.3 Film Storage 120B

Add: U

For the main production pipeline and when agreed with the COMPANY, radiographic film shall be digitized using methods that give adequate resolution and stored in electronic media in an agreed manner with the COMPANY. All radiographic film shall be dried thoroughly prior to viewing and shall be processed to allow storage of the film without deterioration for a minimum period of 5 years At the discretion of COMPANY, the radiographic CONTRACTOR shall satisfactorily demonstrate that the film can be processed, using the site facilities, to have a fog level not greater than 0.3. One radiograph in every 100 shall be subjected to a residual thiosulphate test, to ensure that the film has been suitably processed for 5 years storage.

The procedure for this test

shall form part of the radiographic procedure package for COMPANY approval. Radiographs shall be stored in an environment that will not detrimentally affect the radiographs. Boxes shall be used to store radiographs in multiples of 25, 50 or 100 welds. The weld numbers that apply to the stored radiographs that each box contains shall be clearly visible on each box. 12.5

Manual Ultrasonic Testing 64B

12.5.1 General 12B

Add: U

MUT shall comply with the requirements of ISO 17640. Specifications for MUT procedures shall define the following: 

Type of UT equipment;



Type and dimensions of transducers;



Range of frequencies;



Method of calibration;



Reference block drawing;



Surface requirements;



Coupling medium;



Examination techniques; Page 66 of 75



Weld identification method;



Reporting requirements;



Reference to the applicable WPS;



Temperature range of weld during examination.

12.5.3 Reporting and Evaluation 12B

Add: U

Discontinuity indications having a amplitude above the reference level shall be assessed against the requirements of Table 6 of BS 4515-1 and the following: 

All cracks are unacceptable, regardless of size, location in the weld;



Linear indications (other than cracks) interpreted to be open to the surface are unacceptable if they exceed a length equal to the wall thickness but not exceeding 25mm in total length in continuous 300mm length of weld or 8% of the weld length;



Linear indications interpreted to be buried within the weld are unacceptable if they exceed a length equal to but not exceeding 50mm in total length in a continuous 300mm of weld or 15%of the weld;



Individual defects with a height greater than one pass height (determined after reviewing a macro-section from the main line WPQT) but not greater than 4mm and before interaction assessment shall not be permitted.

Automatic Ultrasonic Testing

12.6 65B

Add: U

The use of automatic ultrasonic testing shall be subject to COMPANY approval in each instance. The qualification of the AUT procedures and production testing shall comply with GIS 43-339. 12.7

Magnetic Particle Testing 6B

Add: U

Magnetic particle testing shall comply with the requirements of ISO 17638. The non-fluorescent wet method of MPE using white contrast paint and an AC yoke (110V) shall be used. Dry powder MPE may be used for repair groove inspection. The AC yoke shall be capable of lifting 4.5 kg at 150 mm pole spacing. Poles shall make maximum contact with the test surface during inspection. DC prods shall not be used.

Page 67 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) All MPE procedures, including the method for determining adequate flux levels in the test area, shall be qualified.

Page 68 of 75



ACCEPTANCE AND RECTIFICATION OF WELDS 12B

13.1

Non-Destructive Testing Acceptance Criteria 67B

13.1.1 General 123B

Add: U

The acceptance standards defined in Section 13.1.2 below shall be the minimum requirement in which radiography is the primary NDT method. Where manual or semiautomatic welding processes are adopted with a conventional bevel configuration and RT is the primary NDE method, MUT shall be used to supplement RT when cracks or planar defects are detected during production welding. MUT shall be used to establish defect size, height and position. If the use of AUT has been approved by COMPANY, Section 13.1.2 below shall be augmented by an ECA in accordance with BS 7910 (Level 3) to determine flaw dimensions and acceptance levels which shall be subject to COMPANY approval (refer to Section 13.1.3 of this specification). When unacceptable flaws occur in more than five consecutive welds or when, in the opinion of the COMPANY, a particular flaw type becomes repetitive in terms of its size and/or location, the cause of the flaws will be investigated by the Welding Engineers working on behalf of the CONTRACTOR and the COMPANY. If necessary, welding will be terminated until the cause of unacceptable flaws has been established and satisfactorily resolved. 13.1.2 Acceptance Criteria Based on Quality Control 124B

Add: U

In areas of weld preparation such as pipe ends, fusion faces and branches, planar defects are not acceptable. Add: U

(BS 4515-1 Table 6f): The maximum length of incomplete penetration, lack of cross penetration or lack of root fusion in any continuous 300mm weld length is limited to but not exceeding 25mm. Add: U

(BS 4515-1 Table 6I) The maximum length of inter run fusion and lack of side fusion in any continuous 300mm weld length is limited to but not exceeding 50mm.

Page 69 of 75



(BS 4515-1 Table 6g) Cracks or crack like defects are unacceptable. In the event that such defects are detected the complete weld shall be cut from the pipeline and the cause of the cracking shall be established to the satisfaction of the COMPANY. Add: U

(BS 4515-1 Table 6k) Tungsten inclusions Tungsten inclusions shall not exceed two per weld and shall be separated by a minimum of 50 mm. The maximum dimension of a tungsten inclusion not to exceed 3mm or 50% of the wall thickness, whichever is smaller. (BS 4515-1 Table 6k) Copper inclusions are not permitted. 13.1.3 Acceptance Criteria Based on Engineering Critical Assessment (ECA) 125B

Add: U

The use of alternative acceptance standards for girth welds shall be subject to COMPANY approval before contract award. The ECA method and testing shall be proposed for COMPANY approval before the commencement of WPQT. The output of the ECA shall be used to develop the weld NDT acceptance standard. The weld acceptance standard shall include an appropriate NDT sizing allowance (see GIS 43339) which shall be clearly documented. In addition to the limits derived from the ECA, the following restrictions on defect size shall apply: 

Individual defects with a height greater than 4 mm (before interaction assessment) shall not be permitted;



No acceptance of any defect >4mm shall be permitted, even if demonstrated through the ECA;



Irrespective of defect height, defects with a length greater than 7 times wall thickness (after interaction assessment) shall not be permitted.

The COMPANY reserves the right to modify the ECA acceptance criteria. Add: U

13.1.4 Suspected Welds 126B

Any weld suspected of not having been produced in accordance with the approved welding procedure shall be cut out, and may be subject to investigation at the discretion of the COMPANY.

Page 70 of 75



Rectification of Welds 68B

13.2.1 Removal of Flaws 127B

Add: U

A WPS for repair welding shall be in accordance with Section 8 of this specification. Defects shall not be repaired in any part of the weld without prior acceptance by the COMPANY. All repairs shall be witnessed by the COMPANY, and the relevant NDT records shall be made available to COMPANY at that time. Internal weld repairs shall not be permitted except for pipe-to-fitting welds where the repair can be undertaken from the open end of the pipe or fitting, subject to successful welding procedure qualification. No more than two separate repairs are allowed in any single weld. Welds with cracks (other than small crater cracks ≤4 mm in length) shall be removed from the pipeline. The welding procedure shall be suspended until the cause is identified and remedial measures implemented to prevent further occurrence. Production welding with the suspended WPS shall only recommence following acceptance from COMPANY Welding Engineer. Small crater cracks shall be removed by local grinding and repaired. For repair of arc burns, see 11.8. 13.2.2 Preparation for Re-Welding 128B

Add: U

The minimum allowable repair length shall not to be less than 50 mm at the bottom of the groove. Metal may be removed by thermal gouging followed by grinding. Grinding shall be used for the last 3 mm through to the root. Air-arc gouging shall be controlled by a procedure documenting the allowed variables as required by AWS C5.3. If there are significant loads or deformation at the weld repair station, verified calculations justifying the excavation size shall be submitted for COMPANY approval. 13.2.4 Re-Welding 129B

Add: U

Internal weld repairs shall not be permitted except for pipe-to-fitting welds where the repair can be undertaken from the open end of the pipe or fitting, subject to successful welding procedure qualification. Page 71 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) When a root repair weld in a pipeline fails to comply with Section 13, the entire circumferential weld shall be cut out and the pipe ends shall be re-bevelled and re-welded. If necessary, a second repair may be attempted for all regions apart from the root. If this second repair fails to meet Section 13, the entire circumferential weld shall be cut out. One full penetration repair is permitted subject to successful welding procedure qualification. Two partial penetration repairs are permitted subject to successful welding procedure qualification. Partial penetration repairs are not permitted within 3mm of the pipe internal surface. The COMPANY may require the full circumference of repaired welds to be re-examined by the same examination method which located the defect. A full record of all repairs shall be maintained by the CONTRACTOR. The record shall be made as each defect is discovered, and shall include the following: 

The weld number;



The type and size of defect;



The circumferential location (defined to an accepted system);



An estimate of the depth (assessed by ultrasonic test where possible);



Mimic taken of repair profile and sketch included detailing (depth, position relative to original weld, width and length of excavation);



Name and/or number of the welder who produced the defect;



Repair welding procedure number;



Name and/or number of repair welder;



Copy of the inspection report for the repair;



Date of repair.

Page 72 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) ANNEX H ADDITIONAL REQUIREMENTS FOR PIPELINES SUBJECT TO HIGH STRAIN LEVELS 13B

H1 69B

Introduction This section applies to pipelines subject to plastic deformation during installation, e.g. installation by reeling. When evaluating the amount of strain at the weld expected during installation, the effects of misalignment, pipe strength variation, and coating stiffness shall be considered.

H.2 70B

General

H.2.1 Linepipe 130B

Pipelines welded in accordance with this appendix shall use linepipe that complies with the additional high strain requirements of GIS 43-311, GIS 43-312, or GIS 43-313. H.2.2 Welding Processes 13B

Welding processes not previously used by the CONTRACTOR with the proposed installation method shall require full scale qualification trials. The extent of the trials shall be determined by COMPANY. Only low hydrogen processes shall be used. H.2.3 Welding Consumables 132B

The consumable selection shall be approved by COMPANY and the consumable should have a track record with the selected installation method. The batch testing of weld consumables described in 7.2.2 shall be undertaken for each batch of welding consumables not tested in the welding procedure qualification. Additionally: -

The strain age testing in accordance with Section H3 shall be performed.

-

The minimum Charpy energy shall be 70J at the impact test temperature.

-

The yield and UTS of the test weld shall exceed the maximum exhibited yield and tensile properties of the production pipe.

H.3 71B

Weld Procedure Qualification Testing

H.3.1 Simulation 13B

The weld procedure qualification welds shall be subjected to full scale bending at the maximum strain predicted during installation. The number of cycles shall be determined from the number of cycles required for installation, plus any contingency operations and

Page 73 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) agreed with COMPANY. Weld repair procedures shall be included in the full scale trial and shall be located to undergo maximum strain. A procedure shall be provided for COMPANY approval detailing the test string and test method. The following points shall be addressed: -

The type and number of welds. Each qualified WPS shall be included in the trial test piece;

-

The length of the test string and the spacing of the welds;

-

The bending frame dimensions and materials;

-

The calculated maximum strain (based on the carousel & pipe diameters);

-

A step-by-step description of the test;

-

The proposed strain rate;

-

Trial report format.

If a successful track record using the same vessel to install pipe of similar properties with similar welding procedures can be demonstrated; then, at COMPANY’s discretion, the full scale trial may be omitted. The spool base, the time between cycles, and the temperature shall be considered when evaluating existing data. H.3.2 Non-Destructive Testing 134B

The weld procedure tests shall be subjected to the visual and non-destructive testing specified in Section 8 of this specification before and after straining. H.3.3 Mechanical Testing 135B

The strength of the welds shall be greater than the strength of the production pipes; however, excessive overmatch should be avoided. H.3.3.1 Evaluation of Weld Procedure – Bending Trial Welds 136B

The welds shall undergo the mechanical testing specified in Section 8 of this specification. However, the transverse tensile locations shall be rotated so that the test pieces are removed from the cardinal points. It is anticipated that this will ensure that the areas undergoing maximum straining will be tested. H.3.3.2 Evaluation of Weld Procedures – Waived Bend Trial 137B

When the full scale trial is waived, the weld procedures shall be subject to the full testing of Section 8 of this specification plus the following strain aged testing. Weld coupons shall

Page 74 of 75


BP Exploration Operating Company Ltd Andrew & Devenick Development Projects Welding and NDT of Carbon Steel Linepipe to BS 4515-1 (2004) undergo 3% tensile strain and ageing at 250°C for one hour before the following tests are performed: -

1 all weld tensile specimen;

-

2 transverse weld metal specimens;

-

1 macro-examination + hardness;

-

2 sets of weld metal Charpy impact specimens;

-

2 sets of fusion line Charpy impact specimens;

-

1 set of fusion line +2 mm Charpy impact specimens;

-

Weld and HAZ CTODs.

The testing shall be undertaken in accordance with Section 8 and the results shall meet the requirements of Section 8 of this specification; however, any large deterioration of properties compared with the unstrained specimens shall be cause for investigation. H.4 72B

Production Welding The maximum permitted pipe misalignment at the weld shall be 1.5 mm unless larger misalignments are demonstrated to be tolerable and are agreed by COMPANY.

Page 75 of 75


Dev-Aad-mp-sp-jpk-1058 Rev b2 Welding and Ndt of Cs Linepipe to Bs 4515-1 (2004)

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