SIST EN ISO 17635:2025

SLOVENSKI STANDARD
01-september-2025
Nadomešča:
SIST EN ISO 17635:2017
Neporušitveno preskušanje zvarnih spojev - Splošna pravila za kovinske materiale
(ISO 17635:2025)
Non-destructive testing of welds - General rules for metallic materials (ISO 17635:2025)
Zerstörungsfreie Prüfung von Schweißverbindungen - Allgemeine Regeln für metallische
Werkstoffe (ISO 17635:2025)
Essais non destructifs des assemblages soudés - Règles générales pour les matériaux
métalliques (ISO 17635:2025)
Ta slovenski standard je istoveten z: EN ISO 17635:2025
ICS:
25.160.40 Varjeni spoji in vari Welded joints and welds
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 17635
EUROPEAN STANDARD
NORME EUROPÉENNE
April 2025
EUROPÄISCHE NORM
ICS 25.160.40 Supersedes EN ISO 17635:2016
English Version
Non-destructive testing of welds - General rules for
metallic materials (ISO 17635:2025)
Essais non destructifs des assemblages soudés - Règles Zerstörungsfreie Prüfung von Schweißverbindungen -
générales pour les matériaux métalliques (ISO Allgemeine Regeln für metallische Werkstoffe (ISO
17635:2025) 17635:2025)
This European Standard was approved by CEN on 9 February 2025.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 17635:2025 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 17635:2025) has been prepared by Technical Committee ISO/TC 44 "Welding
and allied processes" in collaboration with Technical Committee CEN/TC 121 “Welding and allied
processes” the secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by October 2025, and conflicting national standards shall
be withdrawn at the latest by October 2025.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 17635:2016.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 17635:2025 has been approved by CEN as EN ISO 17635:2025 without any modification.

International
Standard
ISO 17635
Fourth edition
Non-destructive testing of welds —
2025-04
General rules for metallic materials
Essais non destructifs des assemblages soudés — Règles générales
pour les matériaux métalliques
Reference number
ISO 17635:2025(en) © ISO 2025
ISO 17635:2025(en)
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ii
ISO 17635:2025(en)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Abbreviated terms . 3
5 Limitations . 3
5.1 Stage of manufacture .3
5.2 Extent of testing .4
5.3 Materials .4
6 Personnel qualification . 4
7 Testing organization . 4
8 Documentation . 4
8.1 Documentation prior to testing .4
8.1.1 General .4
8.1.2 Written procedure .4
8.1.3 Testing plan .4
8.2 Documentation of testing .5
8.2.1 Documentation of individual testing .5
8.2.2 Test report .5
9 Selection of testing method(s) . 5
9.1 General .5
9.2 Butt- and T-joints with full penetration .6
9.3 Butt- and T-joints without full penetration and fillet welds .6
10 Performance of testing . 7
10.1 Determination of standards to be applied .7
10.2 Conditions for testing .7
10.3 Time of testing .7
10.4 Non-acceptable indications .7
10.5 Repaired welds .7
Annex A (normative) Rules and standards to be applied . 8
Annex B (informative) Overview of welding quality standards and NDT-standards .12
Annex C (informative) Non-acceptable indications in case of partial testing . 14
Bibliography .15

iii
ISO 17635:2025(en)
Foreword
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This document was prepared by Technical Committee ISO/TC 44, Welding and allied processes, Subcommittee
SC 5, Testing and inspection of welds, in collaboration with the European Committee for Standardization
(CEN) Technical Committee CEN/TC 121, Welding and allied processes, in accordance with the Agreement on
technical cooperation between ISO and CEN (Vienna Agreement).
This fourth edition cancels and replaces the third edition (ISO 17635:2016), which has been technically
revised.
The main changes are as follows:
— references updated;
— phased-array ultrasonic technique (UT-PA) for thin-walled steel components added;
— ultrasonic technique using total focusing technique (UT-TFM) added;
— Table 1 and Table 3 modified;
— Annex C reintroduced based on a version in ISO 17635:2010 and a flowchart added.
Any feedback or questions on this document should be directed to the user’s
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iv
ISO 17635:2025(en)
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v
ISO 17635:2025(en)
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vi
International Standard ISO 17635:2025(en)
Non-destructive testing of welds — General rules for metallic
materials
1 Scope
This document gives guidelines for the choice of non-destructive testing (NDT) methods for welds in metals
and for the evaluation of the results for quality control purposes, based on quality requirements, material,
weld thickness, welding process and extent of testing.
This document also specifies general rules and standards to be applied to the different types of testing, for
the selection of the method, the techniques and the acceptance levels.
Acceptance levels cannot be a direct interpretation of the quality levels defined in ISO 5817 or ISO 10042.
They are linked to the overall quality of the produced batch of welds.
The requirements specified in this document for acceptance levels for NDT conform with quality levels
stated in ISO 5817 or ISO 10042 (moderate, intermediate, stringent) only on a general basis and not in detail
for each indication.
Annex A gives correlations between quality levels, testing levels and acceptance levels for specific testing
techniques.
Annex B gives an overview on specific testing techniques of standards linked to quality levels, acceptance
levels and testing methods.
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 3452-1, Non-destructive testing — Penetrant testing — Part 1: General principles
ISO 4761:2021, Non-destructive testing of welds — Phased array ultrasonic testing (UT-PA) for thin-walled steel
components — Acceptance levels
ISO 5817:2023
...