ISO 15590-3:2022

Petroleum and natural gas industries — Factory bends, fittings and flanges for pipeline transportation systems — Part 3: Flanges

This document specifies the technical requirements for carbon steel and low-alloy steel forged flanges for use in pipeline transportation systems for the petroleum and natural gas industries as defined in ISO 13623. This document applies to weldneck and blind flanges (full face, raised face, and RTJ groove) as well as anchor, swivel-ring flanges and orifice flanges. This document designates those categories of flanges that meet the industry's need to match ISO 3183 pipe. These flanges are for normal and low-temperature service and include supplementary requirements where required for sour service. Materials for, or the attachment of, factory-welded extensions, bolting materials, gaskets, slip-on flanges or flanged fittings are not covered by this document. This document is not applicable to integrally cast or forged flanges for valves, pumps or other equipment. This document does not cover the selection of the flange category or pressure class. Sizes and pressure classes listed in ISO 7005-1 and applicable to this document are as follows: — DN 10 (NPS 1/2) to DN 1500 (NPS 60); — PN 20 (class 150), PN 50 (class 300), PN 100 (class 600), PN 150 (class 900), PN 250 (class 1500), PN 420 (class 2500).

Industries du pétrole et du gaz naturel — Coudes d'usine, raccords et brides pour systèmes de transport par conduites — Partie 3: Brides

General Information

• Status: Published
• Publication Date: 20-Mar-2022
• ICS: 75.200 - Petroleum products and natural gas handling equipment
• Technical Committee: ISO/TC 67/SC 2 - Pipeline transportation systems
• Drafting Committee: ISO/TC 67/SC 2/WG 10 - Pipeline flanges, fittings and shopbends
• Current Stage: 6060 - International Standard published
• Start Date: 21-Mar-2022
• Due Date: 11-Mar-2022
• Completion Date: 21-Mar-2022

Relations

• Revises: ISO 15590-3:2004 - Petroleum and natural gas industries — Induction bends, fittings and flanges for pipeline transportation systems — Part 3: Flanges
• Effective Date: 23-Apr-2020

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 15590-3
Second edition
2022-03
Petroleum and natural gas
industries — Factory bends,
fittings and flanges for pipeline
transportation systems —
Part 3:
Flanges
Industries du pétrole et du gaz naturel — Coudes d'usine, raccords et
brides pour systèmes de transport par conduites —
Partie 3: Brides
Reference number
ISO 15590-3:2022(E)
© ISO 2022

---------------------- Page: 1 ----------------------
ISO 15590-3:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022
All rights reserved. Unless otherwise specified, or required in the context of its implementation, 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.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
  © ISO 2022 – All rights reserved

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ISO 15590-3:2022(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Symbols and abbreviated terms.3
4.1 Symbols . 3
4.2 Abbreviated terms . 4
5 Designation of flanges . 4
6 Pressure class and design . 5
7 Information supplied by the purchaser . 6
7.1 Principal information . 6
7.2 Supplementary information . 6
8 Manufacturing . 6
8.1 Manufacturing procedure specification . 6
8.2 Starting material . 7
8.3 Hubs . . 7
8.4 Heat treatment. 7
9 Testing and inspection .7
9.1 General requirements . 7
9.2 Extent of testing and inspection . 7
9.3 Chemical composition . 8
9.4 Physical testing . 9
9.4.1 Preparation of test pieces . 9
9.4.2 Tensile testing . 9
9.4.3 Charpy V-notch impact tests . 11
9.4.4 Hardness requirements .12
9.4.5 Metallographic examination . 13
9.4.6 HIC tests . 13
9.4.7 SSC tests . 13
9.5 Non-destructive testing . 13
9.5.1 NDT procedures and personnel . 13
9.5.2 Forging preparation . 13
9.5.3 Visual inspection . 13
9.5.4 MT/PT inspection . 14
9.5.5 Ultrasonic inspection . 14
9.6 Dimensions . 14
9.6.1 Flange dimensions . 14
9.6.2 Tolerances . 15
9.6.3 Flange-face finish .15
9.7 Hydrostatic testing .15
9.8 Weldability . 15
9.9 Repair welding . 15
10 Documentation .16
10.1 Inspection document . 16
10.2 Manufacturing record book . 16
11 Marking . .16
Bibliography .18
iii
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ISO 15590-3:2022(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 of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 67, Materials, equipment and offshore
structures for petroleum, petrochemical and natural gas industries, Subcommittee SC 2 Pipeline
transportation systems.
This second edition cancels and replaces the first edition (ISO 15590-3:2004), which has been
technically revised. The main changes compared to the previous edition are as follows:
a) changed title;
b) added the possibility to execute NDE following the International Standards and EN and ASTM
standards;
c) updated pressure-containment calculations in line with ASME VIII Division 1 or Division 2;
d) updated manufacturing of Hubs, now in line with ASME B16.5;
e) updated heat treatment subclause;
f) modified the chemical analysis in Table 4;
g) reviewed forging preparation requirements;
h) modified dimension of flanges to be in accordance with ASME B16.5, ASME B16.36, ASME B16.47,
ANSI/MSS SP-44;
i) reviewed tolerances to be in accordance with manufacturing standard;
j) reviewed flange-face finish to be in accordance with manufacturing standard;
k) updated applicable standards relating to HIC and SSC;
l) modified Marking to be in accordance with ASME B16.5 requirements.
A list of all parts in the ISO 15590 series can be found on the ISO website.
iv
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ISO 15590-3:2022(E)
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
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INTERNATIONAL STANDARD ISO 15590-3:2022(E)
Petroleum and natural gas industries — Factory bends,
fittings and flanges for pipeline transportation systems —
Part 3:
Flanges
1 Scope
This document specifies the technical requirements for carbon steel and low-alloy steel forged flanges
for use in pipeline transportation systems for the petroleum and natural gas industries as defined in
ISO 13623.
This document applies to weldneck and blind flanges (full face, raised face, and RTJ groove) as well as
anchor, swivel-ring flanges and orifice flanges.
This document designates those categories of flanges that meet the industry's need to match
ISO 3183 pipe. These flanges are for normal and low-temperature service and include supplementary
requirements where required for sour service.
Materials for, or the attachment of, factory-welded extensions, bolting materials, gaskets, slip-on
flanges or flanged fittings are not covered by this document.
This document is not applicable to integrally cast or forged flanges for valves, pumps or other equipment.
This document does not cover the selection of the flange category or pressure class. Sizes and pressure
classes listed in ISO 7005-1 and applicable to this document are as follows:
— DN 10 (NPS 1/2) to DN 1500 (NPS 60);
— PN 20 (class 150), PN 50 (class 300), PN 100 (class 600), PN 150 (class 900), PN 250 (class 1500),
PN 420 (class 2500).
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 148-1, Metallic materials — Charpy pendulum impact test — Part 1: Test method
ISO 377, Steel and steel products — Location and preparation of samples and test pieces for mechanical
testing
ISO 2566-1, Steel — Conversion of elongation values — Part 1: Carbon and low alloy steels
ISO 3183, Petroleum and natural gas industries — Steel pipe for pipeline transportation systems
ISO 4885, Ferrous materials — Heat treatments — Vocabulary
ISO 6892-1, Metallic materials — Tensile testing — Part 1: Method of test at room temperature
ISO 6892-2, Metallic materials — Tensile testing — Part 2: Method of test at elevated temperature
ISO 6507-1:2018, Metallic materials — Vickers hardness test — Part 1: Test method
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ISO 15590-3:2022(E)
ISO 7005-1, Pipe flanges — Part 1: Steel flanges for industrial and general service piping systems
ISO/TS 7705:2017, Guidelines for specifying Charpy V-notch impact prescriptions in steel specifications
ISO 9327-1, Steel forgings and rolled or forged bars for pressure purposes — Technical delivery conditions
— Part 1: General requirements
ISO 9712, Non-destructive testing — Qualification and certification of NDT personnel
ISO 10474, Steel and steel products — Inspection documents
ISO 10893-4, Non-destructive testing of steel tubes — Part 4: Liquid penetrant inspection of seamless and
welded steel tubes for the detection of surface imperfections
ISO 10893-5, Non-destructive testing of steel tubes — Part 5: Magnetic particle inspection of seamless and
welded ferromagnetic steel tubes for the detection of surface imperfections
ISO 13623, Petroleum and natural gas industries — Pipeline transportation systems
ISO 15590-1, Petroleum and natural gas industries — Induction bends, fittings and flanges for pipeline
transportation systems — Part 1: Induction bends
ISO 15590-2, Petroleum and natural gas industries — Factory bends, fittings and flanges for pipeline
transportation systems — Part 2: Fittings
ISO 15590-4, Petroleum and natural gas industries — Factory bends, fittings and flanges for pipeline
transportation systems — Part 4: Factory cold bends
EN 10204, Metallic components: Types of inspection documents
EN 10228-1, Non-destructive testing of steel forgings — Part 1: Magnetic particle inspection
EN 10228-2, Non-destructive testing of steel forgings — Part 2: Penetrant testing
ASME BPVC Section VIII-Rules for construction of pressure vessels division 1
ASME BPVC Section VIII-Rules for construction of pressure vessels division 2
ASME B16.5-20, Pipe flanges and flanged fittings — NPS 1/2 through NPS 24
ASME B16.36, Orifice flanges
ASME B16.47, Large diameter steel flange — NPS 26 through NPS 60
ASTM E112, Standard test methods for determining average grain size
ASTM E165, Standard practice for liquid penetrant testing for general industry
ASTM E709, Standard guide for magnetic particle testing
ANSI/MSS SP-44, Steel pipeline flanges
NACE TM 0177-2016-SG, Standard test method — Laboratory testing of metals for resistance to sulfide
stress cracking and stress corrosion cracking in H S environments
2
NACE TM 0284-2016-SG, Standard test method — Evaluation of pipeline and pressure vessel steels for
resistance to hydrogen-induced cracking
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
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ISO 15590-3:2022(E)
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
ANSI rating class
numerical pressure design class defined in ASME B16.5 and used for reference purposes
Note 1 to entry: The ANSI rating class is designated by the word “Class” followed by a number.
3.2
by agreement
agreed between manufacturer and purchaser
3.3
heat
batch of steel prepared in one steel-making process
[SOURCE: ISO 15590-1:2018, 3.9, modified]
3.4
imperfection
discontinuity or irregularity in the product wall or on the product surface that is detectable through by
inspection methods
3.5
manufacturing procedure specification
MPS
document that specifies the process control parameters and the acceptance criteria applied for all
manufacturing, inspection and testing activities performed during flange manufacture
[SOURCE: ISO 15590-2:2021, 3.5, modified]
3.6
matching pipe
specified pipe grade and thickness to which the flange will be attached
3.7
pressure class
numerical pressure design class expressed in accordance with either the nominal pressure class or the
ANSI rating class
Note 1 to entry: In this document, the pressure class is stated by the nominal pressure class followed by the ANSI
rating class between brackets.
3.8
test unit
flange or test piece of the same type, starting material, wall thickness, heat, manufacturing procedure
specification, and heat treatment condition
4 Symbols and abbreviated terms
4.1 Symbols
A original cross-sectional area of the parallel length of a test specimen
o
E carbon equivalent
c
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ISO 15590-3:2022(E)
P crack measurement parameter (see Table 4)
cm
S sour service
t specified wall thickness at the welding ends for flanges
T minimum design temperature
d,min
T maximum Charpy V-notch test temperature
max
4.2 Abbreviated terms
CE carbon equivalent
DN nominal diameter
HIC hydrogen-induced cracking
HV Vickers hardness
MPS manufacturing procedure specification
MT magnetic particle testing
NDT non-destructive testing
NPS nominal pipe size
PN nominal pressure
RTJ ring type joint
SMYS specified minimum yield strength
SMTS specified minimum tensile strength
SSC sulfide stress cracking
UT ultrasonic testing
5 Designation of flanges
Designation of flanges according to this document, i.e. ISO 15590-3, shall take the form:
ISO 15590-3 YY,
where YY is a textual description of the type of flange designation as specified in Table 1.
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ISO 15590-3:2022(E)
Table 1 — Flange designations
Non-sour service Sour service
Temperature, T Flange designa- Temperature, T Flange designa-
d,min d,min
°C tion °C tion
⩾0 (N) ⩾0 (NS)
<0 (L) <0 (LS)
N: normal service
NS: normal sour service
L: low-temperature service
LS: low-temperature sour service
Flanges with a minimum design temperature lower than 0 °C shall demonstrate proven notch toughness
in accordance with Clause 9.
Flanges intended for sour service shall be so specified by the purchaser and meet the applicable
requirements of Clause 9.
6 Pressure class and design
The flange shall be capable of withstanding an internal pressure equal to the working pressure at the
temperature range required. Maximum pressures for the various pressure classes against temperature
are shown in Table 2.
Table 2 — Maximum pressures as a function of temperature
Temperature PN
20 50 100 150 250 420
°C
Class
150 300 600 900 1 500 2 500
MPa (bar) MPa (bar) MPa (bar) MPa (bar) MPa (bar) MPa (bar)
−30 to 120 1,96 (19,6) 5,11 (51,1) 10,2 (102) 15,3 (153) 25,5 (255) 42,6 (426)
150 1,9 (19) 4,93 (49,3) 9,86 (98,6) 14,8 (148) 22,6 (226) 37,7 (377)
175 1,83 (18,3) 4,75 (47,5) 9,51 (95,1) 14,3 (143) 22,2 (222) 34,1 (341)
200 1,76 (17,6) 4,59 (45,9) 9,17 (91,7) 13,8 (138) 21,9 (219) 36,5 (365)
250 1,7 (17) 4,41 (44,1) 8,86 (88,6) 13,3 (133) 22,5 (225) 35,5 (355)
For any temperature below 30 °C, the rating shall be no greater than the rating shown for −30 °C.
For intermediate temperatures, linear interpolation should be used.
Ratings of flanges for temperatures greater than those given shall be by agreement.
If there are any deviations from the flange dimensions specified in ASME B16.5 or ASME B16.47,
pressure-containment calculations shall be made in accordance with an agreed pressure-vessel design
standard such as ASME BPVC Section VIII, Division 1 or Division 2.
The design calculations shall be available for review.
For pipeline applications, the design criteria shall be in accordance with ISO 7005-1.
NOTE External loads or moments are not covered by this document. However, swivels and anchor flanges
can experience external loads and can be designed using the equivalent pressure method.
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ISO 15590-3:2022(E)
7 Information supplied by the purchaser
7.1 Principal information
The purchaser shall provide the following information in the order given below:
a) flange designation;
b) size and class;
c) quantity of flanges;
d) material grade;
e) wall thickness, specified minimum yield strength and bore size for the matching pipe;
f) flange facing (e.g. raised face, RTJ).
7.2 Supplementary information
If applicable, the purchaser shall specify the following supplementary information:
a) minimum design temperatures;
b) maximum design temperatures;
c) special dimensional requirements;
d) design conditions (design pressure, design factor, corrosion allowance and design code);
e) requirements for supplementary inspection and testing;
f) pipeline design standard or design factors, if different from ISO 13623 (e.g. anchor and swivel
flanges);
g) mechanical property requirements at the maximum design temperature;
h) activities for witnessing and approval by purchaser;
i) marking requirements, if different from this document;
j) packaging and shipping instructions;
k) third-party inspection organization;
l) ISO 10474 or an equivalent regional standard, EN 10204, standard designation of inspection
document required.
8 Manufacturing
8.1 Manufacturing procedure specification
Flanges shall be manufactured in accordance with a documented MPS, which includes all of the
necessary steps to be taken in the manufacture of flanges in accordance with this document. The MPS
shall address the information listed in Clause 7 as applicable. Additional details may be required in the
MPS prior to the commencement of manufacturing.
An approval of the MPS may be required, either by review of the manufacturer’s previous production
data or by performance of the mandatory tests listed in Table 3, at the beginning of production.
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ISO 15590-3:2022(E)
8.2 Starting material
Forgings shall meet the requirements of ISO 9327-1. The starting material for forged flanges shall be
ingot, bloom, billet, slab, plate (for blind flanges only) or bar and shall be fully killed steel. Steel shall
be produced by basic oxygen or electric arc furnace process. Steel shall be made to fine grain practice.
Flanges shall not be machined from bars.
The material designation shall be consistent with ISO 3183.
8.3 Hubs
Pipeline applications shall be in accordance with ASME B16.5-2020, 6.7. Hubs shall be single slope or
dual slope in accordance with ASME B16.5.
8.4 Heat treatment
Heat-treatment vocabulary shall be in accordance with ISO 4885.
Forged flanges shall be normalized, normalized and tempered, or quenched and tempered after forming.
The heat treatment shall be performed in accordance with a documented procedure. The procedure
shall define the following parameters, where appropriate, for the type of heat treatment:
a) heating schedule;
b) soaking temperature;
c) soaking time;
d) cooling schedule;
e) quenching temperature;
f) quenching medium, including commencing and final medium temperature;
g) maximum transfer time to quench.
A record shall be maintained for each heat treatment. Submission of heat treatment record, and heat
treatment chart, shall be specified at PO stage and it shall be included in the inspection document.
The tolerances on soaking temperature shall be ±15 °C and on soaking time ±20 %.
9 Testing and inspection
9.1 General requirements
Testing and inspection shall be carried out on flange forgings after final heat treatment.
If the pipeline installation techniques will require post-weld heat treatment of the flange, additional
testing may be requested to demonstrate that the mechanical properties of the flange are achieved
after post-weld heat treatment. Details of the post-weld heat treatment cycle to be used during pipeline
installation shall be specified.
The test requirements and acceptance criteria shall be by agreement.
9.2 Extent of testing and inspection
Mechanical testing samples shall consist of a prolongation, or sacrificial forging. By agreement, a
separately forged test bar of the same heat as for the final forgings shall be supplied. This test bar shall
receive the same approximate working and shall be heat-treated with the flange forgings it represents.
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ISO 15590-3:2022(E)
The extent of testing and inspection to be performed shall be as stated in Table 3. Locations for the
test pieces to be taken from a flange forging shall be in accordance with ASTM A 370,1/4 t × t, or as
established by agreement.
Flanges heat treated within the tolerance requirements of 8.4 shall be considered as being in the same
heat treatment condition.
Table 3 — Number of tests for destructive physical testing
Type of test Number and frequency of testing
chemical composition one per heat
tensile – base metal one per test unit
impact – base metal one set per test unit, if applicable
through-thickness hardness by agreement for NS and LS
surface hardness by agreement
metallography one per test unit for NS and LS
HIC by agreement
SSC by agreement
NDT by agreement
Surface hardness may be performed during qualification and then used as a non-destructive reference point for production
to quickly determine if production pieces are being produced in the same manner as the qualification piece.
9.3 Chemical composition
The product analysis shall be in accordance with Table 4.
8
  © ISO 2022 – All rights rese
...

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 15590-3
ISO/TC 67/SC 2
Petroleum and natural gas
Secretariat: UNI
industries — Factory bends,
Voting begins on:
2021-12-03 fittings and flanges for pipeline
transportation systems —
Voting terminates on:
2022-01-28
Part 3:
Flanges
Industries du pétrole et du gaz naturel — Coudes d'usine, raccords et
brides pour systèmes de transport par conduites —
Partie 3: Brides
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 15590-3:2021(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. © ISO 2021

---------------------- Page: 1 ----------------------
ISO/FDIS 15590-3:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, 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.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
  © ISO 2021 – All rights reserved

---------------------- Page: 2 ----------------------
ISO/FDIS 15590-3:2021(E)
Contents Page
Foreword .iv
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Symbols and abbreviated terms.3
4.1 Symbols . 3
4.2 Abbreviated terms . 4
5 Designation of flanges . 4
6 Pressure class and design . 5
7 Information supplied by the purchaser . 6
7.1 Principal information . 6
7.2 Supplementary information . 6
8 Manufacturing . 6
8.1 Manufacturing procedure specification . 6
8.2 Starting material . 7
8.3 Hubs . . 7
8.4 Heat treatment. 7
9 Testing and inspection .7
9.1 General requirements . 7
9.2 Extent of testing and inspection . 7
9.3 Chemical composition . 8
9.4 Physical testing . 9
9.4.1 Preparation of test pieces . 9
9.4.2 Tensile testing . 9
9.4.3 Charpy V-notch impact tests . 11
9.4.4 Hardness requirements .12
9.4.5 Metallographic examination . 13
9.4.6 HIC tests . 13
9.4.7 SSC tests . 13
9.5 Non-destructive testing . 13
9.5.1 NDT procedures and personnel . 13
9.5.2 Forging preparation . 13
9.5.3 Visual inspection . 13
9.5.4 MT/PT inspection . 14
9.5.5 Ultrasonic inspection . 14
9.6 Dimensions . 14
9.6.1 Flange dimensions . 14
9.6.2 Tolerances . 15
9.6.3 Flange-face finish . 15
9.7 Hydrostatic testing .15
9.8 Weldability . 15
9.9 Repair welding . 15
10 Documentation .16
10.1 Inspection document . 16
10.2 Manufacturing record book . 16
11 Marking . .16
Bibliography .18
iii
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---------------------- Page: 3 ----------------------
ISO/FDIS 15590-3:2021(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 of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 67, Materials, equipment and offshore
structures for petroleum, petrochemical and natural gas industries, Subcommittee SC 2 Pipeline
transportation systems.
This second edition cancels and replaces the first edition (ISO 15590-3:2004), which has been
technically revised. The main changes compared to the previous edition are as follows:
a) changed title;
b) added the possibility to execute NDE following the International Standards and EN and ASTM
standards;
c) updated pressure-containment calculations in line with ASME VIII Division 1 or Division 2;
d) updated manufacturing of Hubs, now in line with ASME B16.5;
e) updated heat treatment subclause;
f) modified the chemical analysis in Table 4;
g) reviewed forging preparation requirements;
h) modified dimension of flanges to be in accordance with ASME B16.5, ASME B16.36, ASME B16.47,
ANSI/MSS SP-44;
i) reviewed tolerances to be in accordance with manufacturing standard;
j) reviewed flange-face finish to be in accordance with manufacturing standard;
k) updated applicable standards relating to HIC and SSC;
l) modified Marking to be in accordance with ASME B16.5 requirements.
A list of all parts in the ISO 15590 series can be found on the ISO website.
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ISO/FDIS 15590-3:2021(E)
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
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ISO/FDIS 15590-3:2021(E)
Introduction
Further or differing requirements might be needed for individual applications. This document is
not intended to inhibit a manufacturer from offering, or the purchaser from accepting, alternative
equipment or engineering solutions for the individual application. This can be particularly applicable
where there is innovative or developing technology. Where an alternative is offered, the manufacturer
should identify any variations from this document and provide details.
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FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 15590-3:2021(E)
Petroleum and natural gas industries — Factory bends,
fittings and flanges for pipeline transportation systems —
Part 3:
Flanges
1 Scope
This document specifies the technical requirements for carbon steel and low-alloy steel forged flanges
for use in pipeline transportation systems for the petroleum and natural gas industries as defined in
ISO 13623.
This document applies to weldneck and blind flanges (full face, raised face, and RTJ groove) as well as
anchor, swivel-ring flanges and orifice flanges.
This document designates those categories of flanges that meet the industry's need to match
ISO 3183 pipe. These flanges are for normal and low-temperature service and include supplementary
requirements where required for sour service.
Materials for, or the attachment of, factory-welded extensions, bolting materials, gaskets, slip-on
flanges or flanged fittings are not covered by this document.
This document is not applicable to integrally cast or forged flanges for valves, pumps or other equipment.
This document does not cover the selection of the flange category or pressure class. Sizes and pressure
classes listed in ISO 7005-1 and applicable to this document are as follows:
— DN 10 (NPS 1/2) to DN 1500 (NPS 60);
— PN 20 (class 150), PN 50 (class 300), PN 100 (class 600), PN 150 (class 900), PN 250 (class 1500),
PN 420 (class 2500).
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 148-1, Metallic materials — Charpy pendulum impact test — Part 1: Test method
ISO 377, Steel and steel products — Location and preparation of samples and test pieces for mechanical
testing
ISO 2566-1, Steel — Conversion of elongation values — Part 1: Carbon and low alloy steels
ISO 3183, Petroleum and natural gas industries — Steel pipe for pipeline transportation systems
ISO 4885, Ferrous materials — Heat treatments — Vocabulary
ISO 6892-1, Metallic materials — Tensile testing — Part 1: Method of test at room temperature
ISO 6892-2, Metallic materials — Tensile testing — Part 2: Method of test at elevated temperature
ISO 6507-1:2018, Metallic materials — Vickers hardness test — Part 1: Test method
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ISO/FDIS 15590-3:2021(E)
ISO 7005-1, Pipe flanges — Part 1: Steel flanges for industrial and general service piping systems
ISO/TS 7705:2017, Guidelines for specifying Charpy V-notch impact prescriptions in steel specifications
ISO 9327-1, Steel forgings and rolled or forged bars for pressure purposes — Technical delivery conditions
— Part 1: General requirements
ISO 9712, Non-destructive testing — Qualification and certification of NDT personnel
ISO 10474, Steel and steel products — Inspection documents
ISO 10893-4, Non-destructive testing of steel tubes — Part 4: Liquid penetrant inspection of seamless and
welded steel tubes for the detection of surface imperfections
ISO 10893-5, Non-destructive testing of steel tubes — Part 5: Magnetic particle inspection of seamless and
welded ferromagnetic steel tubes for the detection of surface imperfections
ISO 13623, Petroleum and natural gas industries — Pipeline transportation systems
ISO 15590-1, Petroleum and natural gas industries — Induction bends, fittings and flanges for pipeline
transportation systems — Part 1: Induction bends
ISO 15590-2, Petroleum and natural gas industries — Factory bends, fittings and flanges for pipeline
transportation systems — Part 2: Fittings
ISO 15590-4, Petroleum and natural gas industries — Factory bends, fittings and flanges for pipeline
transportation systems — Part 4: Factory cold bends
EN 10204, Metallic components: Types of inspection documents
EN 10228-1, Non-destructive testing of steel forgings — Part 1: Magnetic particle inspection
EN 10228-2, Non-destructive testing of steel forgings — Part 2: Penetrant testing
ASME BPVC Section VIII-Rules for construction of pressure vessels division 1
ASME BPVC Section VIII-Rules for construction of pressure vessels division 2
ASME B16.5-20, Pipe flanges and flanged fittings — NPS 1/2 through NPS 24
ASME B16.36, Orifice flanges
ASME B16.47, Large diameter steel flange — NPS 26 through NPS 60
ASTM E112, Standard test methods for determining average grain size
ASTM E165, Standard practice for liquid penetrant testing for general industry
ASTM E709, Standard guide for magnetic particle testing
ANSI/MSS SP-44, Steel pipeline flanges
NACE TM 0177-2016-SG, Standard test method — Laboratory testing of metals for resistance to sulfide
stress cracking and stress corrosion cracking in H S environments
2
NACE TM 0284-2016-SG, Standard test method — Evaluation of pipeline and pressure vessel steels for
resistance to hydrogen-induced cracking
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
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ISO/FDIS 15590-3:2021(E)
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
ANSI rating class
numerical pressure design class defined in ASME B16.5 and used for reference purposes
Note 1 to entry: The ANSI rating class is designated by the word “Class” followed by a number.
3.2
by agreement
agreed between manufacturer and purchaser
3.3
heat
batch of steel prepared in one steel-making process
[SOURCE: ISO 15590-1:2018, 3.9, modified]
3.4
imperfection
discontinuity or irregularity in the product wall or on the product surface that is detectable through by
inspection methods
3.5
manufacturing procedure specification
MPS
document that specifies the process control parameters and the acceptance criteria applied for all
manufacturing, inspection and testing activities performed during flange manufacture
[SOURCE: ISO 15590-2:2021, 3.5, modified]
3.6
matching pipe
specified pipe grade and thickness to which the flange will be attached
3.7
pressure class
numerical pressure design class expressed in accordance with either the nominal pressure class or the
ANSI rating class
Note 1 to entry: In this document, the pressure class is stated by the nominal pressure class followed by the ANSI
rating class between brackets.
3.8
test unit
flange or test piece of the same type, starting material wall thickness, heat, manufacturing procedure
specification, and heat treatment condition
4 Symbols and abbreviated terms
4.1 Symbols
A original cross-sectional area of the parallel length of a test specimen
o
E carbon equivalent
c
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ISO/FDIS 15590-3:2021(E)
P crack measurement parameter (see Table 4)
cm
S sour service
t specified wall thickness at the welding ends for flanges
T minimum design temperature
d,min
T maximum Charpy V-notch test temperature
max
4.2 Abbreviated terms
CE carbon equivalent
DN nominal diameter
HIC hydrogen-induced cracking
HV Vickers hardness
MPS manufacturing procedure specification
MT magnetic particle testing
NDT non-destructive testing
NPS nominal pipe size
PN nominal pressure
RTJ ring type joint
SMYS specified minimum yield strength
SMTS specified minimum tensile strength
SSC sulfide stress cracking
UT ultrasonic testing
5 Designation of flanges
Designation of flanges according to this document, i.e. ISO 15590-3, shall take the form:
ISO 15590-3 YY,
where YY is a textual description of the type of flange designation as specified in Table 1.

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ISO/FDIS 15590-3:2021(E)
Table 1 — Flange designations
Non-sour service Sour service
Temperature, T Flange designa- Temperature, T Flange designa-
d,min d,min
°C tion °C tion
⩾0 (N) ⩾0 (NS)
<0 (L) <0 (LS)
N: normal service
NS: normal sour service
L: low-temperature service
LS: low-temperature sour service
Flanges with a minimum design temperature lower than 0 °C shall demonstrate proven notch toughness
in accordance with Clause 9.
Flanges intended for sour service shall be so specified by the purchaser and meet the applicable
requirements of Clause 9.
6 Pressure class and design
The flange shall be capable of withstanding an internal pressure equal to the working pressure at the
temperature range required. Maximum pressures for the various pressure classes against temperature
are shown in Table 2.
Table 2 — Maximum pressures as a function of temperature
Temperature PN
20 50 100 150 250 420
°C
Class
150 300 600 900 1 500 2 500
MPa (bar) MPa (bar) MPa (bar) MPa (bar) MPa (bar) MPa (bar)
−30 to 120 1,96 (19,6) 5,11 (51,1) 10,2 (102) 15,3 (153) 25,5 (255) 42,6 (426)
150 1,9 (19) 4,93 (49,3) 9,86 (98,6) 14,8 (148) 22,6 (226) 37,7 (377)
175 1,83 (18,3) 4,75 (47,5) 9,51 (95,1) 14,3 (143) 22,2 (222) 34,1 (341)
200 1,76 (17,6) 4,59 (45,9) 9,17 (91,7) 13,8 (138) 21,9 (219) 36,5 (365)
250 1,7 (17) 4,41 (44,1) 8,86 (88,6) 13,3 (133) 22,5 (225) 35,5 (355)
For any temperature below 30 °C, the rating shall be no greater than the rating shown for −30 °C.
For intermediate temperatures, linear interpolation should be used.
Ratings of flanges for temperatures greater than those given shall be by agreement.
If there are any deviations from the flange dimensions specified in ASME B16.5 or ASME B16.47,
pressure-containment calculations shall be made in accordance with an agreed pressure-vessel design
standard such as ASME BPVC Section VIII, Division 1 or Division 2.
The design calculations shall be available for review.
For pipeline applications, the design criteria shall be in accordance with ISO 7005-1.
NOTE External loads or moments are not covered by this document. However, swivels and anchor flanges
can experience external loads and can be designed using the equivalent pressure method.
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ISO/FDIS 15590-3:2021(E)
7 Information supplied by the purchaser
7.1 Principal information
The purchaser shall provide the following information in the order given below:
a) flange designation;
b) size and class;
c) quantity of flanges;
d) material grade;
e) wall thickness, specified minimum yield strength and bore size for the matching pipe;
f) flange facing (e.g. raised face, RTJ).
7.2 Supplementary information
If applicable, the purchaser shall specify the following supplementary information:
a) minimum design temperatures;
b) maximum design temperatures;
c) special dimensional requirements;
d) design conditions (design pressure, design factor, corrosion allowance and design code);
e) requirements for supplementary inspection and testing;
f) pipeline design standard or design factors, if different from ISO 13623 (e.g. anchor and swivel
flanges);
g) mechanical property requirements at the maximum design temperature;
h) activities for witnessing and approval by purchaser;
i) marking requirements, if different from this document;
j) packaging and shipping instructions;
k) third-party inspection organization.
l) ISO 10474 or an equivalent regional standard, EN 10204, standard designation of inspection
document required.
8 Manufacturing
8.1 Manufacturing procedure specification
Flanges shall be manufactured in accordance with a documented MPS, which includes all of the
necessary steps to be taken in the manufacture of flanges in accordance with this document. The MPS
shall address the information listed in Clause 7 as applicable. Additional details may be required in the
MPS prior to the commencement of manufacturing.
An approval of the MPS may be required, either by review of the manufacturer’s previous production
data or by performance of the mandatory tests listed in Table 3, at the beginning of production.
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ISO/FDIS 15590-3:2021(E)
8.2 Starting material
Forgings shall meet the requirements of ISO 9327-1. The starting material for forged flanges shall be
ingot, bloom, billet, slab, plate (for blind flanges only) or bar and shall be fully killed steel. Steel shall
be produced by basic oxygen or electric arc furnace process. Steel shall be made to fine grain practice.
Flanges shall not be machined from bars.
The material designation shall be consistent with ISO 3183.
8.3 Hubs
Pipeline applications shall be in accordance with ASME B16.5-2020, 6.7. Hubs shall be single slope or
dual slope in accordance with ASME B16.5.
8.4 Heat treatment
Heat-treatment vocabulary shall be in accordance with ISO 4885.
Forged flanges shall be normalized, normalized and tempered, or quenched and tempered after forming.
The heat treatment shall be performed in accordance with a documented procedure. The procedure
shall define the following parameters, where appropriate, for the type of heat treatment:
a) heating schedule;
b) soaking temperature;
c) soaking time;
d) cooling schedule;
e) quenching temperature;
f) quenching medium, including commencing and final medium temperature;
g) maximum transfer time to quench.
A record shall be maintained for each heat treatment. Submission of heat treatment record, and heat
treatment chart, shall be specified at PO stage and it shall be included in the inspection document.
The tolerances on soaking temperature shall be ±15 °C and on soaking time ±20 %.
9 Testing and inspection
9.1 General requirements
Testing and inspection shall be carried out on flange forgings after final heat treatment.
If the pipeline installation techniques will require post-weld heat treatment of the flange, additional
testing may be requested to demonstrate that the mechanical properties of the flange are achieved
after post-weld heat treatment. Details of the post-weld heat treatment cycle to be used during pipeline
installation shall be specified.
The test requirements and acceptance criteria shall be by agreement.
9.2 Extent of testing and inspection
Mechanical testing samples shall consist of a prolong
...