ISO 9328-5:2018

Steel flat products for pressure purposes - Technical delivery conditions - Part 5: Weldable fine grain steels, thermomechanically rolled

ISO 9328-5:2018 specifies the requirements for flat products for pressure equipment, made of thermomechanically rolled weldable fine grain steels as specified in Tables A.1 and B.1. The steels are not suitable for hot forming. Until now, no sufficient data for the standardization of the elevated temperature properties of these steels are available. If their use at such temperatures is intended, the conditions for this are specially agreed upon between the interested parties. 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 5: Aciers soudables à grains fins, laminés thermomécaniquement

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 9328-5:2011 - Steel flat products for pressure purposes - Technical delivery conditions - Part 5: Weldable fine grain steels, thermomechanically rolled
• Effective Date: 30-Jul-2016

Overview - ISO 9328-5:2018 (steel flat products for pressure purposes)

ISO 9328-5:2018 specifies technical delivery conditions for thermomechanically rolled, weldable fine grain steels used as flat products for pressure equipment (plates, strips). It is part of the ISO 9328 series and complements the general requirements of ISO 9328-1. The standard covers chemical composition, mechanical properties, delivery condition, inspection and testing requirements for grades listed in Annex A (European design codes) and Annex B (ASME-type design codes).
Key limitations: these steels are not suitable for hot forming, and elevated-temperature properties are not standardized - use at high temperature must be agreed between purchaser and manufacturer. Fine grain steels are defined as ferritic grain size 6 or finer (ISO 643).

Key topics and technical requirements

• Material scope and designation: Grades organized into series (basic, and low-temperature series down to −40 °C / −50 °C / −60 °C depending on annex). Designation follows ISO 9328-1.
• Delivery condition: Products supplied in the thermomechanically rolled condition.
• Chemical composition: Cast (heat) analysis and allowable deviations for product analysis are specified (see Tables A.1 and B.1). Option to agree carbon-equivalent values.
• Mechanical properties: Yield/tensile and impact requirements referenced in Annex Tables (A.3–A.4, B.3–B.4). Optionally a 40 J impact energy can be specified at certain temperatures.
• Weldability: Steels must be suitable for current welding processes; manufacturer can supply welding procedure data. Guidance on avoiding cold cracking and cautions about excessive post‑weld heat treatment (PWHT) affecting properties are included.
• Inspection & testing: Specifies types of inspection, sampling, tests (including impact testing direction for Annex B), and inspection certificates (example: certificate 3.1 per ISO 10474).
• Dimensions, surface condition, internal soundness: Requirements and tolerances aligned with ISO 9328-1.

Practical applications and users

Who uses ISO 9328-5:2018

• Steel producers and plate manufacturers (production, heat analysis, delivery).
• Purchasers and specifiers of pressure equipment materials (pressure vessels, boilers, piping, storage tanks).
• Welding engineers, fabricators and welding procedure qualification teams.
• Design engineers using European or ASME-type codes who need compatible material specifications.
• Inspection bodies and certification authorities verifying conformity and issuing inspection certificates.

Practical value

• Ensures consistent material quality for pressure purposes.
• Facilitates specification of weldable fine grain steels for low-temperature service.
• Supports procurement, testing, and welding procedure development with clear acceptance criteria.

Related standards

• ISO 9328-1 (general requirements)
• ISO 643 (ferritic grain size)
• ISO 10474 (inspection certificates)
• EN 1011-1 / EN 1011-2, IIS/IIW 382-71 (welding guidance)

Keywords: ISO 9328-5:2018, steel flat products, pressure purposes, thermomechanically rolled, weldable fine grain steels, delivery conditions, chemical composition, mechanical properties, weldability, ASME, European design codes.

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 9328-5
Fourth edition
2018-02
Steel flat products for pressure
purposes — Technical delivery
conditions —
Part 5:
Weldable fine grain steels,
thermomechanically rolled
Produits plats en acier pour service sous pression — Conditions
techniques de livraison —
Partie 5: Aciers soudables à grains fins, laminés
thermomécaniquement
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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Fax [phone]
[e-mail]
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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 . 2
4.1 Classification . 2
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 . 3
6 Requirements . 3
6.1 Steelmaking process . 3
6.2 Delivery condition . 3
6.3 Chemical composition . 3
6.4 Mechanical properties . 4
6.5 Surface condition . 4
6.6 Internal soundness . 4
6.7 Weldability . 4
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 . 6
Annex A (normative) Chemical composition and mechanical properties of products
delivered in accordance with European design codes . 7
Annex B (normative) Chemical composition and mechanical properties of products
delivered in accordance with ASME-type design codes.11
Annex C (informative) Steel designations in accordance with this document and
designation of comparable steel grades in national or regional standards .14
Bibliography .15
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
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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 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 fourth edition cancels and replaces the third edition (ISO 9328-5:2011), 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 content of the document has been generally updated.
— in Table B.1, “B ≤ 0,001 0” has been added and the specifications of “P” and “S” have been changed.
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 9328-5:2018(E)
Steel flat products for pressure purposes — Technical
delivery conditions —
Part 5:
Weldable fine grain steels, thermomechanically rolled
1 Scope
This document specifies the requirements for flat products for pressure equipment, made of
thermomechanically rolled weldable fine grain steels as specified in Tables A.1 and B.1. The steels are
not suitable for hot forming.
Until now, no sufficient data for the standardization of the elevated temperature properties of these
steels are available. If their use at such temperatures is intended, the conditions for this are specially
agreed upon between the interested parties.
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.M, PT…M);
b) series with low temperature properties down to −40 °C (P.ML1, PT…ML1);
c) series with low temperature properties down to −50 °C (P.ML2 – grades of Annex A only);
d) series with low temperature properties down to −60 °C (PT.ML3 – grades of Annex B only).
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.4, footnote ).
5.2 Options
A number of options are specified in this document. These are listed below under a) to g). 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) specification of an impact energy of 40 J (see Note to 6.4 and Table A.4);
b
c) decreased minimum Al content (see Table B.1, footnote );
total
c
d) increased maximum carbon content for the grade PT550ML1 (see Table B.1, footnote );
d
e) increased maximum silicon content for the grade PT550M (see Table B.1, footnote );
b
f) other test requirements for the impact test (see Table B.4, footnote );
g) tests on simulated heat-treated samples (see 6.7.2).
2 © ISO 2018 – All rights reserved

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 P355ML2 as specified in this document, with inspection
certificate 3.1 as specified in ISO 10474, is designated as follows:
10 plates – 50 × 2 000 × 10 000 – ISO 9328-5 P355ML2 – Inspection certificate 3.1
6 Requirements
6.1 Steelmaking process
Shall be in accordance with ISO 9328-1.
6.2 Delivery condition
The products complying with this document are supplied in the thermomechanically rolled condition.
6.3 Chemical composition
6.3.1 The requirements in Table A.1 and Table B.1 apply for the chemical composition according to the
cast (heat) analysis.
6.3.2 The product analysis may deviate from the specified values of the cast (heat) analysis given in
Table A.1 and Table B.1 by the values given in Table 1.
6.3.3 For steel grades covered by this document, a carbon-equivalent value according to Table A.2 (for
steel grades in Annex A) or Table B.2 (for steel grades in Annex B) may be agreed upon at the time of
enquiry and order.
Table 1 — Permissible deviations of the chemical composition f
...