ISO 9328-3:2018

Steel flat products for pressure purposes - Technical delivery conditions - Part 3: Weldable fine grain steels, normalized

ISO 9328-3:2018 specifies the requirements for flat products for pressure equipment made of 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 as steels with a ferritic grain size of 6 or finer when tested in accordance with ISO 643. NOTE 2 This document offers the possibility to 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 3: Aciers soudables à grains fins, normalisés

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 9328-3:2011 - Steel flat products for pressure purposes - Technical delivery conditions - Part 3: Weldable fine grain steels, normalized
• Effective Date: 30-Jul-2016

Overview

ISO 9328-3:2018 - "Steel flat products for pressure purposes - Technical delivery conditions - Part 3: Weldable fine grain steels, normalized" specifies the technical delivery requirements for flat steel products intended for pressure equipment. It covers weldable fine grain steels (ferritic grain size 6 or finer per ISO 643) and applies together with the general requirements of ISO 9328-1. The standard supports ordering and supply in accordance with both European design codes and ASME-type design codes (see Annexes A and B).

Key topics and requirements

• Scope and classification: Defines steel grades and qualities (room temperature, elevated temperature, low temperature, special low temperature) and their designation rules referencing ISO 9328-1.
• Delivery condition: Default supply is normalized; untreated (+AR) delivery or simulated normalized tests are possible if agreed at order.
• Chemical composition: Cast (heat) analysis limits are in Tables A.1 and B.1; permissible deviations for product analysis are specified (Table 1). Option to agree carbon-equivalent limits.
• Mechanical properties and testing: Requirements for tensile and impact properties, including options for mid-thickness samples, longitudinal test piece verification, and elevated-temperature R values (Tables A.3–A.5, B.3–B.4).
• Weldability and HIC: Provisions for weldability statements and optional hydrogen‑induced cracking (HIC) evaluation (Annex D).
• Inspection and documentation: Specifies inspection types, sampling, marking and inspection certificates (example: Inspection certificate 3.1 per ISO 10474).
• Dimensions and tolerances, internal soundness, surface condition: Delivery requirements for manufacturing and quality control.
• Normative references: Key referenced standards include ISO 9328-1, ISO 643 (grain size), ISO 4948, ISO 10474 and EN/ASME-related guidance.

Practical applications and users

ISO 9328-3 is used where reliable, weldable flat steel products are required for pressure equipment and vessels. Typical users:

• Steel producers and plate mills specifying chemical and mechanical delivery requirements
• Pressure vessel and boiler manufacturers selecting plate material for welding and fabrication
• Fabricators and welders assessing weldability and normalized condition suitability
• Design engineers working to European or ASME-type pressure codes
• Inspection and certification bodies issuing inspection certificates and verifying compliance
• Procurement specialists placing orders for steel plates used in oil & gas, petrochemical, power generation and pressure-retaining components

Related standards

• ISO 9328-1 - General requirements for steel flat products for pressure purposes
• ISO 643 - Ferritic grain size testing
• ISO 10474 - Inspection documents and certificates
• EN 10028-3 - Harmonized data (aligned with Annex A)

Keywords: ISO 9328-3, weldable fine grain steels, normalized, pressure equipment, steel flat products, technical delivery conditions, ASME, European design codes, chemical composition, mechanical properties.

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 9328-3
Fourth edition
2018-02
Steel flat products for pressure
purposes — Technical delivery
conditions —
Part 3:
Weldable fine grain steels, normalized
Produits plats en acier pour service sous pression — Conditions
techniques de livraison —
Partie 3: Aciers soudables à grains fins, normalisés
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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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 . 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 . 5
6.7 Weldability . 5
6.8 Dimensions and tolerances . 5
6.9 Calculation of mass . 5
6.10 Resistance to hydrogen-induced cracking. 5
7 Inspection . 6
7.1 Types of inspection and inspection documents . 6
7.2 Tests to be carried out . 6
7.3 Retests, sorting and reprocessing . 6
8 Sampling . 6
9 Test methods . 6
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.13
Annex C (informative) Steel designations in accordance with this document and
designation of comparable steel grades in national or regional standards .17
Annex D (informative) Evaluation of resistance to hydrogen-induced cracking .18
Bibliography .19
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 9328-3:2011), which has been technically
revised. The following changes have been made:
— the term “product thickness” has been replaced with “nominal thickness”;
— classification of the steels, examples of ordering and statements concerning weldability have been
revised;
— the technical data in Annex A have been aligned with EN 10028-3.
— 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 9328-3:2018(E)
Steel flat products for pressure purposes — Technical
delivery conditions —
Part 3:
Weldable fine grain steels, normalized
1 Scope
This document specifies the requirements for flat products for pressure equipment made of 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 as steels with a ferritic grain size of 6 or finer when tested in
accordance with ISO 643.
NOTE 2 This document offers the possibility to 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
EN 10314, Method for the derivation of minimum values of proof strength of steel at elevated temperatures
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
4.1.1 The steel grades covered by this document are given in four qualities:
a) the room temperature quality (P.N; PT…N);
b) the elevated temperature quality (P.NH; PT…NH);
c) the low temperature quality (P.NL1; PT…NL1);
d) the special low temperature quality (P.NL2).
4.1.2 In accordance with ISO 4948-1 and ISO 4948-2, the grades P275NH, P275NL1, P355N, P355NH,
P355NL1, P355NL2, PT400N, PT400NH, PT400NL1, PT440N, PT440NH, PT440NL1, PT490N and
PT490NH are alloy-quality steels, the grades P275NL2 and the grades P420NH, P420NL1, P420NL2,
P460NH, P460NL1, P460NL2, PT520N and PT520NH are alloyed special steels.
4.2 Designation
Shall be in accordance with ISO 9328-1.
NOTE 1 Steel grades in Annex A are classified in accordance with their yield strength; 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
b
agreed upon (see 9.2 and Table B.4, footnote ).
5.2 Options
A number of options are specified in this document. These are listed below under a) to r). 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) delivery condition other than specified in Tables A.3 and B.3 (see 6.2.1);
b) tests in the simulated normalized condition (see 6.2.2);
c) delivery of products in the untreated condition (see 6.2.3);
d) maximum carbon-equivalent value (see 6.3.3);
e) specification of an impact energy value of 40 J (see Note to 6.4.1 and Table A.3);
f) application of the R values of Table A.4 for the corresponding P…NL1 and P.NL2 grades (see 6.4.2);
p0,2
g) test on simulated heat-treated samples (see 6.7.2);
h) hydrogen-induced cracking (HIC) test in accordance with Annex D (see 6.10);
i) mid-thickness test pieces for the impact test and/or tensile test (see Clause 8);
j) verification of impact energy for longitudinal test pieces (see 9.3);
d
k) tensile properties for increased nominal thicknesses (see Table A.3, footnote );
c
l) R values at elevated temperatures for increased nominal thicknesses (see Table A.4, footnote );
p0,2
2 © ISO 2018 – All rights reserved

f
m) modified values for R and R for grades P460NH and P460NL1 (see Table A.3, footnote );
eH m
b
o) altered maximum value for Cr, Cu, Mo, Nb, Ni, Ti and V (see Table B.1, footnote );
c
p) Al content < 0,020 % (see Table B.1, footnote );
total
d
q) increased maximum carbon contents for grades PT…NH (see Table B.1, footnote );
c
r) other test requirements for the impact test (see Table B.4, footnote ).
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 P275NL2 as specified in this document, to be delivered
with inspection certificate 3.1 as specified in ISO 10474, is designated as follows:
10 plates – 50 × 2 000 × 10 000 – ISO 9328-3 P275NL2 – Inspection certificate 3.1
6 Requirements
6.1 Steelmaking process
Shall be in accordance with ISO 9328-1.
6.2 Delivery condition
6.2.1 Unless otherwise agreed at the time of enquiry and order (see 6.2.3), the products covered by
this document shall be supplied in the normalized condition.
For steels with minimum yield strength ≥ 460 MPa, delayed cooling or additional tempering is
permitted. If such a treatment is performed, this shall be noted in the inspection document.
6.2.2 At the discretion of the manufacturer, normalizing may be replaced with normalizing rolling for the
steel grades in Annex A (see ISO 9328-1:2018, 3.1). In this case, additional tests in the simulated normalized
condition with an agreed frequency of testing may be agreed upon at the time of enquiry and order, to verify
that the obtained properties also comply with the standard requirements (see 5.2, Option 2).
6.2.3 If so agreed at the time of enquiry and order, products covered by this document may be delivered
in the untreated condition. The products delivered in untreated conditions shall be appropriately marked
(+AR) to denote that heat treatment has not been performed.
6.2.4 For products delivered untreated, the specified tests shall be carried out by the manufacture on
test pieces in the simulated normalized condition (but see 6.2.1).
NOTE Tests in a simulated heat-treated condition are carried out to verify the suitability of the final product
in the usual delivery condition. However, they do not discharge the processor from the obligation of providing
proof of the specified properties in the finished product when adequately heat treated.
6.3 Chemical composition
6.3.1 The requirements of Tables A.1 and 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
Tables A.1 and 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
(steel grades in Annex A) or Table B.2 (steel grades in Annex B) may be agreed upon at the time of
enquiry and order.
Table 1 — Permissible deviations of the product analysis from the specified limits given in
Tables A.1 and B.1 for the cast (heat) analysis
Specified limit of the cast (heat) analysis
a
Permissible deviation of the product analysis
Element according to Tables A.1 and B.1
% by mass % by mass
b
C ≤
...