ISO 9328-6:2018

Steel flat products for pressure purposes - Technical delivery conditions - Part 6: Weldable fine grain steels, quenched and tempered

ISO 9328-6:2018 specifies the requirements for flat products for pressure equipment made of quenched and tempered weldable fine grain steels as specified in Tables A.1 and B.1. The requirements and definitions of ISO 9328‑1 also apply to this document. NOTE 1 Fine grain steels are understood to be steels with a ferritic grain size of 6 or finer when tested in accordance with ISO 643. NOTE 2 This document offers the possibility of specifying products in accordance with European design codes and ASME-type design codes.

Produits plats en acier pour service sous pression — Conditions techniques de livraison — Partie 6: Aciers soudables à grains fins, trempés et revenus

General Information

• Status: Published
• Publication Date: 31-Jan-2018
• ICS: 77.140.30 - Steels for pressure purposes
• ICS: 77.140.50 - Flat steel products and semi-products
• Technical Committee: ISO/TC 17/SC 10 - Steel for pressure purposes
• Drafting Committee: ISO/TC 17/SC 10 - Steel for pressure purposes
• Current Stage: 9060 - Close of review
• Completion Date: 02-Sep-2028

Relations

• Revises: ISO 9328-6:2011 - Steel flat products for pressure purposes - Technical delivery conditions - Part 6: Weldable fine grain steels, quenched and tempered
• Effective Date: 30-Jul-2016

Overview

ISO 9328-6:2018 - "Steel flat products for pressure purposes - Technical delivery conditions - Part 6" specifies delivery requirements for quenched and tempered, weldable fine grain steels used in pressure equipment. It supplements the general rules of ISO 9328‑1 and covers chemical composition, mechanical properties, weldability, inspection and testing for the flat products listed in Annexes A and B. The standard supports both European design codes and ASME-type design approaches.

Key topics and technical requirements

• Scope and classification
  • Applies to alloyed, fine grain steels (ferritic grain size 6 or finer per ISO 643) supplied in the quenched-and-tempered condition.
• Chemical composition
  • Cast (heat) analysis limits are given in Tables A.1 / B.1; permitted product-analysis deviations are defined.
  • Option to specify a carbon-equivalent value (CEV) at order stage.
• Mechanical properties
  • Tensile, yield and impact requirements are specified in Annexes A and B, with options for elevated- and low-temperature grades and optional 40 J impact levels.
• Weldability
  • Products shall be suitable for current welding processes; manufacturers can supply welding condition data from weld procedure tests.
  • Guidance on cold cracking risk, PWHT effects, and option to test simulated post‑weld heat‑treated samples.
• Delivery, inspection and testing
  • Delivery condition = quenched and tempered. Dimensions, tolerances, internal soundness, sampling, testing, marking and inspection procedures align with ISO 9328‑1.
  • Inspection documentation options include inspection certificate 3.1 per ISO 10474.
• Options for purchaser
  • Several ordering options (e.g., test directions for impact tests, elevated temperature tensile properties, thicker product requirements).

Applications

• Design, manufacture and fabrication of pressure vessels, boilers, heat exchangers and piping components where high-strength, weldable plates are required.
• Use when components must meet specified mechanical behavior at ambient, low or elevated temperatures and when compatibility with European or ASME design methods is needed.
• Useful for specifying materials in procurement, quality control, and welding procedure development.

Who uses this standard

• Plate producers and steel mills
• Pressure equipment manufacturers and fabricators
• Welding engineers and procedure developers
• QA/QC inspectors and materials purchasers
• Design engineers who require conformity with European or ASME-type codes

Related standards

• ISO 9328-1 (General requirements for steel flat products for pressure purposes)
• ISO 643 (Ferritic grain size testing)
• ISO 10474 (Inspection documents - certificates)
• EN 10028-6 (aligned technical data for some grades)
• Welding guidance: EN 1011 and IIW/IIS documents referenced for weld procedures

Keywords: ISO 9328-6:2018, weldable fine grain steels, quenched and tempered, steel flat products for pressure purposes, pressure equipment steel, chemical composition, mechanical properties, weldability, ASME, EN 10028-6.

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 9328-6
Third edition
2018-02
Steel flat products for pressure
purposes — Technical delivery
conditions —
Part 6:
Weldable fine grain steels, quenched
and tempered
Produits plats en acier pour service sous pression — Conditions
techniques de livraison —
Partie 6: Aciers soudables à grains fins, trempés et revenus
Reference number
©
ISO 2018
© ISO 2018
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
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CH-1214 Vernier, Geneva, Switzerland
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Fax [phone]
[e-mail]
www.iso.org
Published in Switzerland
ii © ISO 2018 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Classification and designation . 1
4.1 Classification . 1
4.2 Designation . 2
5 Information to be supplied by the purchaser. 2
5.1 Mandatory information . 2
5.2 Options . 2
5.3 Example for ordering . 2
6 Requirements . 3
6.1 Steelmaking process . 3
6.2 Delivery condition . 3
6.3 Chemical composition . 3
6.4 Mechanical properties . 3
6.5 Surface condition . 3
6.6 Internal soundness . 3
6.7 Weldability . 3
6.8 Dimensions and tolerances . 5
6.9 Calculation of mass . 5
7 Inspection . 5
7.1 Types of inspection and inspection documents . 5
7.2 Tests to be carried out . 5
7.3 Retests, sorting and reprocessing . 5
8 Sampling . 5
9 Test methods . 5
10 Marking . 5
Annex A (normative) Chemical composition and mechanical properties of products
delivered in accordance with European design codes . 6
Annex B (normative) Chemical composition and mechanical properties of products
delivered in accordance with ASME-type design codes.10
Annex C (informative) Steel designations in accordance with this document and
designation of comparable steel grades in national or regional standards .12
Bibliography .13
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
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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
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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 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 the following
URL: www .iso .org/ iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 17, Steel, Subcommittee SC 10, Steel for
pressure purposes.
This third edition cancels and replaces the second edition (ISO 9328-6:2011), which has been technically
revised. The following changes have been made:
— the term “product thickness” has been replaced with “nominal thickness”;
— the example of ordering has been revised;
— the technical data in Annex A have been aligned with EN 10028-6;
— in Table B.1, the specifications of “P” and “S” have been changed.
— the content of the document has been generally updated.
A list of all the parts in the ISO 9328 series can be found on the ISO website.
iv © ISO 2018 – All rights reserved

INTERNATIONAL STANDARD ISO 9328-6:2018(E)
Steel flat products for pressure purposes — Technical
delivery conditions —
Part 6:
Weldable fine grain steels, quenched and tempered
1 Scope
This document specifies the requirements for flat products for pressure equipment made of quenched
and tempered weldable fine grain steels as specified in Tables A.1 and B.1. The requirements and
definitions of ISO 9328-1 also apply to this document.
NOTE 1 Fine grain steels are understood to be steels with a ferritic grain size of 6 or finer when tested in
accordance with ISO 643.
NOTE 2 This document offers the possibility of specifying products in accordance with European design codes
and ASME-type design codes.
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 4948-1, Steels — Classification — Part 1: Classification of steels into unalloyed and alloy steels based
on chemical composition
ISO 4948-2, Steels — Classification — Part 2: Classification of unalloyed and alloy steels according to main
quality classes and main property or application characteristics
ISO 9328-1:2018, Steel flat products for pressure purposes — Technical delivery conditions — Part 1:
General requirements
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 9328-1 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http:// www .electropedia .org/
— ISO Online browsing platform: available at https:// www .iso .org/ obp
4 Classification and designation
4.1 Classification
In accordance with ISO 4948-1 and ISO 4948-2, all steel grades covered by this document are alloyed
special steels.
4.2 Designation
Shall be in accordance with ISO 9328-1.
This document covers the steel grades specified in Annexes A and B in four series:
a) basic series (P.Q; PT…Q);
b) series with elevated temperature properties (P.QH, PT…QH);
c) series with low temperature properties down to −40 °C (P.QL1);
d) series with low temperature properties down to −60 °C (P.QL2, PT…QL2).
NOTE 1 The steel grades in Annex A are classified in accordance with their yield strength; the steel grades in
Annex B are classified in accordance with their tensile strength.
NOTE 2 Information on the designation of comparable steel grades in national or regional standards is given
in Annex C.
5 Information to be supplied by the purchaser
5.1 Mandatory information
Shall be in accordance with ISO 9328-1.
Additionally, for steel grades in accordance with Annex B, the test direction for the impact test shall be
a
agreed upon (see Clause 9 and Table B.3, footnote ).
5.2 Options
A number of options are specified in this document. These are listed below under a) to j). Additionally,
the relevant options of ISO 9328-1 apply. If the purchaser does not indicate a wish to implement any of
these options at the time of enquiry and order, the products shall be supplied in accordance with the
basic specification (see ISO 9328-1):
a) carbon-equivalent value (see 6.3.3);
b) tensile properties at elevated temperatures for steel grades PT…QH (see 6.4);
c) specification of an impact energy of 40 J (see the Note to 6.4 and Table A.3);
c
d) lower copper content and maximum tin content (see Table A.1, footnote );
b
e) mechanical properties for thicknesses > 150 mm (see Table A.2, footnote );
b
f) applicability of elevated temperature values for QL grades (see Table A.4, footnote );
c
g) increased maximum carbon content for the grade PT520Q (see Table B.1, footnote );
d
h) increased maximum carbon content for the grade PT550QL2 (see Table B.1, footnote );
b
i) other test requirements for the impact test (see Table B.3, footnote );
j) tests on simulated heat-treated samples (see 6.7.2).
5.3 Example for ordering
An order of 10 plates with nominal dimensions thickness = 50 mm, width = 2 000 mm, length =
10 000 mm, made of a steel grade with the name P355QL2 as specified in this document, with inspection
certificate 3.1 as specified in ISO 10474, is designate
...