Petroleum and natural gas industries -- Materials for use in H2S-containing environments in oil and gas production

ISO 15156-3:2015 gives requirements and recommendations for the selection and qualification of CRAs (corrosion-resistant alloys) and other alloys for service in equipment used in oil and natural gas production and natural gas treatment plants in H2S-containing environments whose failure can pose a risk to the health and safety of the public and personnel or to the environment. It can be applied to help avoid costly corrosion damage to the equipment itself. It supplements, but does not replace, the materials requirements of the appropriate design codes, standards, or regulations. ISO 15156-3:2015 addresses the resistance of these materials to damage that can be caused by sulfide stress-cracking (SSC), stress-corrosion cracking (SCC), and galvanically induced hydrogen stress cracking (GHSC). ISO 15156-3:2015 is concerned only with cracking. Loss of material by general (mass loss) or localized corrosion is not addressed. Table 1 provides a non-exhaustive list of equipment to which this part of ISO 15156 is applicable, including permitted exclusions. ISO 15156-3:2015 applies to the qualification and selection of materials for equipment designed and constructed using load controlled design methods. For design utilizing strain-based design methods, see ISO 15156‑1:2015, Clause 5. ISO 15156-3:2015 is not necessarily suitable for application to equipment used in refining or downstream processes and equipment.

Industries du pétrole et du gaz naturel -- Matériaux pour utilisation dans des environnements contenant de l'hydrogène sulfuré (H2S) dans la production de pétrole et de gaz

General Information

Status
Published
Publication Date
19-Aug-2015
Current Stage
6060 - International Standard published
Start Date
03-Jul-2015
Completion Date
20-Aug-2015
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INTERNATIONAL ISO
STANDARD 15156-3
Third edition
2015-09-01
Petroleum and natural gas
industries — Materials for use in H2S-
containing environments in oil and
gas production —
Part 3:
Cracking-resistant CRAs (corrosion-
resistant alloys) and other alloys
Industries du pétrole et du gaz naturel — Matériaux pour utilisation
dans des environnements contenant de l’hydrogène sulfuré (H2S)
dans la production de pétrole et de gaz —
Partie 3: ARC (alliages résistants à la corrosion) et autres alliages
résistants à la fissuration
Reference number
ISO 15156-3:2015(E)
ISO 2015
---------------------- Page: 1 ----------------------
ISO 15156-3:2015(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2015, Published in Switzerland

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form

or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior

written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of

the requester.
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copyright@iso.org
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ii © ISO 2015 – All rights reserved
---------------------- Page: 2 ----------------------
ISO 15156-3:2015(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 2

3 Terms and definitions ..................................................................................................................................................................................... 3

4 Symbols and abbreviated terms ........................................................................................................................................................... 4

5 Factors affecting the cracking-resistance of CRAs and other alloys in H S-

containing environments ............................................................................................................................................................................ 5

6 Qualification and selection of CRAs and other alloys with respect to SSC, SCC, and

GHSC in H S-containing environments.......................................................................................................................................... 5

6.1 General ........................................................................................................................................................................................................... 5

6.2 Evaluation of materials properties ........................................................................................................................................ 6

6.2.1 Hardness of parent metals ...................................................................................................................................... 6

6.2.2 Cracking-resistance properties of welds..................................................................................................... 6

6.2.3 Cracking-resistance properties associated with other fabrication methods ............... 8

6.3 PREN ................................................................................................................................................................................................................ 8

7 Purchasing information and marking ............................................................................................................................................ 8

7.1 Information that should be supplied for material purchasing ...................................................................... 8

7.2 Marking, labelling, and documentation ............................................................................................................................. 9

Annex A (normative) Environmental cracking-resistant CRAs and other alloys (including

Table A.1 — Guidance on the use of the materials selection tables) ...........................................................10

Annex B (normative) Qualification of CRAs for H S-service by laboratory testing ..........................................56

Annex C (informative) Information that should be supplied for material purchasing .................................66

Annex D (informative) Materials chemical compositions and other information .............................................68

Annex E (informative) Nominated sets of test conditions ...........................................................................................................84

Bibliography .............................................................................................................................................................................................................................85

© ISO 2015 – All rights reserved iii
---------------------- Page: 3 ----------------------
ISO 15156-3:2015(E)
Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work of preparing International Standards is normally carried out

through ISO technical committees. Each member body interested in a subject for which a technical

committee has been established has the right to be represented on that committee. International

organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.

ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of

electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

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

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www.iso.org/patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation on the meaning of ISO specific terms and expressions related to conformity

assessment, as well as information about ISO’s adherence to the WTO principles in the Technical

Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information

The committee responsible for this document is ISO/TC 67, Materials, equipment and offshore structures

for petroleum, petrochemical and natural gas industries.

This third edition cancels and replaces the second edition (ISO 15156-3:2009), which has been

technically revised with the following changes:

— replacement in the Scope of the term “conventional elastic design criteria” by the term “load

controlled design methods”;

— refinements to 6.3 to require the use of absolute values when F is calculated for use in this part

PREN
of ISO 15156;

— acceptance of the environmental limits for low carbon 300 series stainless steels also for their dual

certified grades;

— changes to some of the tables of Annex A to more conservatively reflect the current knowledge of

the limits of use of some materials;

— changes to the definition of acceptable limits to in situ production environment pH in some

tables of Annex A;

— additions to a number of tables of Annex A of new sets of acceptable environmental limits for (new)

materials and their associated metallurgical requirements.

ISO 15156 consists of the following parts, under the general title Petroleum and natural gas industries —

Materials for use in H2S-containing environments in oil and gas production:
— Part 1: General principles for selection of cracking-resistant materials

— Part 2: Cracking-resistant carbon and low-alloy steels, and the use of cast irons

— Part 3: Cracking-resistant CRAs (corrosion-resistant alloys) and other alloys
iv © ISO 2015 – All rights reserved
---------------------- Page: 4 ----------------------
ISO 15156-3:2015(E)
Introduction

The consequences of sudden failures of metallic oil and gas field components associated with their

exposure to H S-containing production fluids led to the preparation of the first edition of NACE MR0175

which was published in 1975 by the National Association of Corrosion Engineers, now known as NACE

International.

The original and subsequent editions of NACE MR0175 established limits of H S partial pressure above

which precautions against sulfide stress-cracking (SSC) were always considered necessary. They

also provided guidance for the selection and specification of SSC-resistant materials when the H S

thresholds were exceeded. In more recent editions, NACE MR0175 has also provided application limits

for some corrosion-resistant alloys in terms of environmental composition and pH, temperature, and

H S partial pressures.

In separate developments, the European Federation of Corrosion issued EFC Publication 16 in 1995 and

EFC Publication 17 in 1996. These documents are generally complementary to those of NACE, though

they differed in scope and detail.

In 2003, the publication of the ISO 15156-series and NACE MR0175/ISO 15156 was completed for the

first time. These technically identical documents utilized the above sources to provide requirements

and recommendations for materials qualification and selection for application in environments

containing wet H S in oil and gas production systems. They are complemented by NACE TM0177 and

NACE TM0284 test methods.

The revision of this part of ISO 15156 involves a consolidation of all changes agreed and

published in the Technical Circular 1, ISO 15156-3:2009/Cir.1:2011(E), Technical Circular 2,

ISO 15156-3:2009/Cir.2:2013(E), Technical Circular 3, ISO 15156-3:2009/Cir.3:2014(E), and Technical

Circular 4, ISO 15156-3:2009/Cir.4:2014(E), published by the ISO 15156 Maintenance Agency secretariat

at DIN, Berlin.

The changes were developed by and approved by the ballot of representative groups from within the oil

and gas production industry. The great majority of these changes stem from issues raised by document

users. A description of the process by which these changes were approved can be found at the ISO 15156

maintenance website: www.iso.org/iso15156maintenance.
Technical Circular ISO 15156-3:2009/Cir.2:2013 and Technical Circular

ISO 15156-3:2009/Cir.3:2014 intend that an informative Annex F should be published for this part of

ISO 15156 that was to give an alternative presentation of the information contained in the materials

selection tables of Annex A.

During final editing of this part of ISO 15156, a number of technical errors were found in the transfer of

information between the materials selection tables of Annex A and Table F.1. In order not to delay the

publication of the new edition of this part of ISO 15156, the ISO 15156 Maintenance Agency agreed that

the proposed Annex F should not be published at this time.

When found necessary by oil and gas production industry experts, future interim changes to this part of

ISO 15156 will be processed in the same way and will lead to interim updates to this part of ISO 15156

in the form of Technical Corrigenda or Technical Circulars. Document users should be aware that such

documents can exist and can impact the validity of the dated references in this part of ISO 15156.

The ISO 15156 Maintenance Agency at DIN was set up after approval by the ISO Technical Management

Board given in document 34/2007. This document describes the make up of the agency which includes

experts from NACE, EFC and ISO/TC 67, and the process for approval of amendments. It is available from

the ISO 15156 maintenance website and from the ISO/TC 67 Secretariat. The website also provides

access to related documents that provide more detail of ISO 15156 maintenance activities.

© ISO 2015 – All rights reserved v
---------------------- Page: 5 ----------------------
INTERNATIONAL STANDARD ISO 15156-3:2015(E)
Petroleum and natural gas industries — Materials for use in
H2S-containing environments in oil and gas production —
Part 3:
Cracking-resistant CRAs (corrosion-resistant alloys) and
other alloys

WARNING — CRAs (corrosion-resistant alloys) and other alloys selected using this part of ISO 15156

are resistant to cracking in defined HS-containing environments in oil and gas production,

but not necessarily immune to cracking under all service conditions. It is the equipment user’s

responsibility to select the CRAs and other alloys suitable for the intended service.

1 Scope

This part of ISO 15156 gives requirements and recommendations for the selection and qualification of

CRAs (corrosion-resistant alloys) and other alloys for service in equipment used in oil and natural gas

production and natural gas treatment plants in H S-containing environments whose failure can pose

a risk to the health and safety of the public and personnel or to the environment. It can be applied to

help avoid costly corrosion damage to the equipment itself. It supplements, but does not replace, the

materials requirements of the appropriate design codes, standards, or regulations.

This part of ISO 15156 addresses the resistance of these materials to damage that can be caused by

sulfide stress-cracking (SSC), stress-corrosion cracking (SCC), and galvanically induced hydrogen

stress cracking (GHSC).

This part of ISO 15156 is concerned only with cracking. Loss of material by general (mass loss) or

localized corrosion is not addressed.

Table 1 provides a non-exhaustive list of equipment to which this part of ISO 15156 is applicable,

including permitted exclusions.

This part of ISO 15156 applies to the qualification and selection of materials for equipment designed and

constructed using load controlled design methods. For design utilizing strain-based design methods,

see ISO 15156-1:2015, Clause 5.

This part of ISO 15156 is not necessarily suitable for application to equipment used in refining or

downstream processes and equipment.
© ISO 2015 – All rights reserved 1
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ISO 15156-3:2015(E)
Table 1 — List of equipment
ISO 15156 is applicable to materials used for the Permitted exclusions
following equipment

Drilling, well construction, and well-servicing Equipment exposed only to drilling fluids of controlled

equipment composition
Drill bits
Blowout-preventer (BOP) shear blades
Drilling riser systems
Work strings
Wireline and wireline equipment
Surface and intermediate casing
Wells including subsurface equipment, gas lift Sucker rod pumps and sucker rods
equipment, wellheads, and christmas trees
Electric submersible pumps
Other artificial lift equipment
Slips

Flow-lines, gathering lines, field facilities, and field Crude oil storage and handling facilities operating at

processing plants a total absolute pressure below 0,45 MPa (65 psi)
Water-handling equipment Water-handling facilities operating at a total absolute
pressure below 0,45 MPa (65 psi)
Water injection and water disposal equipment
Natural gas treatment plants —

Transportation pipelines for liquids, gases, and Lines handling gas prepared for general commercial

multi-phase fluids and domestic use
For all equipment above Components loaded only in compression
See ISO 15156-2:2015, A.2.3.2.3 for more information.
See ISO 15156-2:2015, A.2.3.2.1 for more information.

Wireline lubricators and lubricator connecting devices are not permitted exclusions.

For sucker rod pumps and sucker rods, reference can be made to NACE MR0176.

2 Normative references

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

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

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

ISO 6507-1, Metallic materials — Vickers hardness test — Part 1: Test method
ISO 6508-1, Metallic materials — Rockwell hardness test — Part 1: Test method

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

ISO 7539-7, Corrosion of metals and alloys — Stress corrosion testing — Part 7: Method for slow strain rate

testing

ISO 10423, Petroleum and natural gas industries — Drilling and production equipment — Wellhead and

christmas tree equipment

ISO 11960, Petroleum and natural gas industries — Steel pipes for use as casing or tubing for wells

ISO 15156-1:2015, Petroleum and natural gas industries — Materials for use in H2S-containing environments

in oil and gas production — Part 1: General principles for selection of cracking-resistant materials

2 © ISO 2015 – All rights reserved
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ISO 15156-3:2015(E)

ISO 15156-2:2015, Petroleum and natural gas industries — Materials for use in H2S-containing

environments in oil and gas production — Part 2: Cracking-resistant carbon and low alloy steels, and the

use of cast irons

ASTM A747/A747M , Standard Specification for Steel Castings, Stainless, Precipitation Hardening

ASTM E29, Standard Practice for Using Significant Digits in Test Data to Determine Conformance with

Specifications

ASTM E562, Standard Test Method for Determining Volume Fraction by Systematic Manual Point Count

EFC Publications Number 17 , Corrosion resistant alloys for oil and gas production: guidelines on general

requirements and test methods for H2S service

NACE CORROSION/95 , Paper 47, Test methodology for elemental sulfur-resistant advanced materials for

oil and gas field equipment

NACE CORROSION/97 Paper 58, Rippled strain rate test for CRA sour service materials selection

NACE TM0177, Laboratory testing of metals for resistance to sulfide stress cracking and stress corrosion

cracking in H2S environments

NACE TM0198, Slow strain rate test method for screening corrosion resistant alloys (CRAs) for stress

corrosion cracking in sour oilfield service
SAE AMS-2430, Shot Peening, Automatic
SAE — ASTM, Metals and alloys in the Unified Numbering System, ISBN 0-7680-04074
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 15156-1, ISO 15156-2, and the

following apply.
3.1
ageing

change in metallurgical properties that generally occurs slowly at room temperature (natural ageing)

and more rapidly at higher temperature (artificial ageing)
3.2
anneal

heat to and hold at a temperature appropriate for the specific material and then cool at a suitable rate

for such purposes as reducing hardness, improving machineability, or obtaining desired properties

3.3
austenite
face-centred cubic crystalline phase of iron-based alloys
3.4
duplex stainless steel
austenitic/ferritic stainless steel

stainless steel (3.13) whose microstructure at room temperature consists primarily of a mixture of

austenite (3.3) and ferrite (3.5)

1) ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, USA.

2) European Federation for Corrosion, available from The Institute of Materials, 1 Carlton House Terrace, London

SW1Y 5DB, UK [ISBN 0-901716-95-2].
3) NACE International, P.O. Box 2183140, Houston, TX 77218-8340, USA.

4) Society of Automotive Engineers (SAE), 400 Commonwealth Drive, Warrendale, PA 15096-0001, USA.

© ISO 2015 – All rights reserved 3
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ISO 15156-3:2015(E)
3.5
ferrite
body-centred cubic crystalline phase of iron-based alloys
3.6
ferritic stainless steel

stainless steel (3.13) whose microstructure at room temperature consists predominantly of ferrite (3.5)

3.7
galvanically induced hydrogen stress cracking
GHSC

cracking that results due to the presence of hydrogen in a metal induced in the cathode of a galvanic

couple and tensile stress (residual and/or applied)
3.8
martensite

hard, supersaturated solid solution of carbon in iron characterized by an acicular (needle-like)

microstructure
3.9
martensitic steel

steel in which a microstructure of martensite (3.8) can be attained by quenching at a cooling rate fast

enough to avoid the formation of other microstructures
3.10
pitting-resistance equivalent number
PREN
PREN

number developed to reflect and predict the pitting resistance of a CRA based upon the proportions of

the elements Cr, Mo, W, and N in the chemical composition of the alloy
Note 1 to entry: See 6.3 for further information.
3.11
production environment

natural occurring produced fluids without contamination from chemicals that will temporarily or

continuously reduce the in situ pH

Note 1 to entry: Flow back of chemicals for stimulation and scale removal may temporarily reduce the pH

significantly and some continuously injected chemicals, such as scale inhibitors, can continuously reduce pH.

3.12
solid solution
single crystalline phase containing two or more elements
3.13
stainless steel

steel containing 10,5 % mass fraction or more chromium, possibly with other elements added to secure

special properties
4 Symbols and abbreviated terms

For the purposes of this document, the symbols and abbreviated terms shown in ISO 15156-1 and

ISO 15156-2 apply, some of which are repeated for the purpose of convenience, together with the following:

AYS actual yield strength
CR c-ring
CRA corrosion-resistant alloy
4 © ISO 2015 – All rights reserved
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ISO 15156-3:2015(E)
HBW Brinell hardness
HRB Rockwell hardness (scale B)
HRC Rockwell hardness (scale C)
pCO partial pressure of CO
2 2
pH S partial pressure of H S
2 2
PWHT post-weld heat treatment
S elemental sulfur
RSRT rippled strain rate test
SSRT slow strain rate test
UNS unified (alloy) numbering system
5 Factors affecting the cracking-resistance of CRAs and other alloys in H S-
containing environments

The cracking behaviour of CRAs and other alloys in H S-containing environments can be affected by

complex interactions of parameters including the following:

— chemical composition, strength, heat treatment, microstructure, method of manufacture, and

finished condition of the material;
— H S partial pressure or equivalent dissolved concentration in the water phase;
— acidity (in situ pH) of the water phase;
— chloride or other halide ion concentration;
— presence of oxygen, sulfur, or other oxidants;
— exposure temperature;
— pitting resistance of the material in the service environment;
— galvanic effects;
— total tensile stress (applied plus residual);
— exposure time.

These factors shall be considered when using this part of ISO 15156 for the selection of materials

suitable for environments containing H S in oil and gas production systems.

6 Qualification and selection of CRAs and other alloys with respect to SSC, SCC,

and GHSC in H S-containing environments
6.1 General

CRAs and other alloys shall be selected for their resistance to SSC, SCC, and/or GHSC as required by the

intended service.

Compliance of a CRA or other alloy with this part of ISO 15156 implies cracking-resistance within defined

environmental service limits. These limits are dependent on the material type or the individual alloy.

© ISO 2015 – All rights reserved 5
---------------------- Page: 10 ----------------------
ISO 15156-3:2015(E)

To enable qualification and/or selection of CRAs and other alloys, the equipment purchaser can be

required to provide information on the proposed conditions of exposure to the equipment supplier.

In defining the severity of H S-containing environments, exposures that can occur during system

upsets or shutdowns, etc. shall also be considered. Such exposures can include unbuffered, low pH

condensed water. The limits given in the tables in Annex A are for production environments and do not

cover conditions occurring during injection or flowback of chemicals that can reduce the in situ pH.

CRAs and other alloys shall be selected using Annex A or following qualification by successful

laboratory testing in accordance with Annex B. Qualification based on satisfactory field experience is

also acceptable. Such qualification shall comply with ISO 15156-1.

In Annex A, materials are identified by materials groups. Within each group, alloys are identified by

materials type (within compositional limits) or as individual alloys. Acceptable metallurgical conditions

and environmental limits are given for which alloys are expected to resist cracking. Environmental

limits are given for H S partial pressure, temperature, chloride concentration, and elemental sulfur.

A CRA or other alloy can be qualified by testing for use under operating conditions that are more

severe than the environmental limits given in Annex A. Similarly, a CRA or other alloy can be qualified

for use in different metallurgical conditions (higher strength, alternative heat treatment, etc.) to those

given in Annex A.

The documentation of qualifications performed in accordance with Annex B shall meet the requirements

in ISO 15156-1:2015, Clause 9.

The equipment user shall verify qualifications (see B.2.2) and retain documentation supporting the

materials selections made.
6.2 Evaluation of materials properties
6.2.1 Hardness of parent metals

If hardness measurements on parent metal are specified, sufficient hardness tests shall be made

to establish the actual hardness of the CRA or other alloy being examined. Individual HRC readings

exceeding the value permitted by this part of ISO 15156 may be considered acceptable if the average

of several readings taken within close proximity does not exceed the value permitted by this part

of ISO 15156 and no individual reading is greater than 2 HRC above the specified value. Equivalent

requirements shall apply to other methods of hardness measurement when specified in this part of

ISO 15156 or referenced in a manufacturing specification.

The conversion of hardness readings to or from other scales is material-dependent. The user may

establish the required conversion tables.

NOTE The number and location of hardness tests on parent metal are not specified in ISO 15156 (all parts).

6.2.2 Cracking-resistance properties of welds
6.2.2.1 General

The metallurgical changes that occur when welding CRAs and other alloys can affect their susceptibility

to SSC, SCC, and/or GHSC. Welded joints can have a greater susceptibility to cracking than the parent

material(s) joined.

The equipment user may allow the cracking susceptibility of weldments to govern the limits of safe

service conditions for a fabricated system.

Processes and consumables used in welding should be selected in accordance with good practice and to

achieve the required corrosion and cracking resistances.
6 © ISO 2015 – All rights reserved
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ISO 15156-3:2015(E)

Welding shall be carried out in compliance with appropriate codes and standards as agreed between

the supplier and the purchaser. Welding procedure specifications (WPSs) and procedure qualification

records (PQRs) shall be available for inspection by the equipment user.

Welding PQRs shall include documented evidence demonstrating satisfactory cracking resistance

under conditions at least as severe as those of the proposed application. Such evidence shall be based

upon one or more of the following:

— compliance with the requirements and recommendations for the specific materials group of Annex A

(see also 6.2.2.2 and 6.2.2.3);
— weld cracking-resistance qualification testing in accordance with Annex B;

— documented field experience modelled upon that specified for parent materials in ISO 15156-1.

The requirements and recommendations given in Annex A might not be appropriate for all combinations

of parent and weld metals used in the fabrication of equipment and components. The equipment user

may require evidence of successful cracking-resistance testing as part of the welding procedure

qualification to ensure the weldment produced provides adequate resistance to SSC, SCC, and GHSC for

the application.

6.2.2.2 Qualification of welding procedures in accordance with Annex A based upon hardness

6.2.2.2.1 General

The qualification of welding procedures for sour service shall, if specified in Annex A, include hardness

testing in accordance with 6.2.2.2.2, 6.2.2.2.3 and 6.2.2.2.4.
6.2.2.2.2 Hardness testing methods for welding procedure qualification

Hardness testing for welding procedure qualification shall be carried out using Vickers HV 10 or HV 5

methods in accordance with
...

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