Non-destructive testing of welds - Radiographic testing - Part 2: X- and gamma-ray techniques with digital detectors (ISO 17636-2:2022, Corrected version 2023-02)

This document specifies techniques of digital radiography with the object of enabling satisfactory and repeatable results. The techniques are based on generally recognized practice and fundamental theory of the subject.
This document applies to the digital radiographic testing of fusion welded joints in metallic materials. It applies to the joints of plates and pipes. Besides its conventional meaning, “pipe”, as used in this document, covers other cylindrical bodies such as tubes, penstocks, boiler drums and pressure vessels.
This document specifies the requirements for digital radiographic X- and gamma-ray testing by either computed radiography (CR) or radiography with digital detector arrays (DDAs) of the welded joints of metallic plates and tubes for the detection of imperfections. It includes manual and automated inspection with DDAs.
Digital detectors provide a digital grey value image which can be viewed and evaluated using a computer (Annex E). This document specifies the recommended procedure for detector selection and radiographic practice. Selection of computer, software, monitor, printer and viewing conditions are important, but are not the main focus of this document. The procedure specified in this document provides the minimum requirements for radiographic practice which permits exposure and acquisition of digital radiographs with equivalent sensitivity for the detection of imperfections as film radiography (specified in ISO 17636-1).
This document does not specify acceptance levels for any of the indications found on the digital radiographs. ISO 10675 provides information on acceptance levels for weld inspection.
If contracting parties apply lower test criteria, it is possible that the quality achieved will be significantly lower than when this document is strictly applied.

Zerstörungsfreie Prüfung von Schweißverbindungen - Durchstrahlungsprüfung - Teil 2: Röntgen- und Gammastrahlungstechniken mit digitalen Detektoren (ISO 17636-2:2022, korrigierte Fassung 2023-02)

Dieses Dokument legt Techniken der digitalen Durchstrahlungsprüfung mit dem Ziel fest, zufriedenstellende und wiederholbare Ergebnisse zu erreichen. Die Techniken beruhen auf allgemein anerkannten Vorgehensweisen und den grundlegenden Theorien zum Thema.
Dieses Dokument ist anwendbar für die digitale Durchstrahlungsprüfung von Schmelzschweißverbindungen in metallischen Werkstoffen. Es ist anwendbar für Schweißverbindungen von Platten und Rohren. Neben der konventionellen Bedeutung werden in diesem Dokument unter der Benennung „Rohr“ auch andere zylindrische Körper wie Druckleitungen, Kesseltrommeln und Druckbehälter verstanden.
Dieses Dokument legt die Anforderungen an die digitale Durchstrahlungsprüfung von Schweißverbindungen an Metallplatten und -rohren mit Röntgen- und Gammastrahlen unter Anwendung entweder der Computer-Radiographie (CR) oder der Radiographie mit digitalen Matrixdetektoren (DDA, en: Digital Detector Arrays) fest, die dem Nachweis von Unregelmäßigkeiten dient. Es umfasst die manuelle und automatische Prüfung mittels DDA.
Digitale Detektoren liefern ein Bild mit digitalen Grauwerten, das mit einem Computer betrachtet und ausgewertet werden kann (Anhang E). Dieses Dokument legt die empfohlenen Verfahren für die Auswahl des Detektors und der Durchstrahlungstechnik fest. Die Auswahl von Computer, Software, Monitor, Drucker und Betrachtungsbedingungen ist von Bedeutung, bildet jedoch nicht den Schwerpunkt dieses Dokuments. Das in diesem Dokument festgelegte Verfahren enthält die Mindestanforderungen an das Durchstrahlungsverfahren zur Gewinnung digitaler Durchstrahlungsaufnahmen mit einer Empfindlichkeit für den Nachweis von Unregelmäßigkeiten, die der Radiographie mit Filmen (festgelegt in ISO 17636 1) gleichwertig ist.
Dieses Dokument legt keine Zulässigkeitsgrenzen für Anzeigen in den digitalen Durchstrahlungsaufnahmen fest. ISO 10675 enthält Informationen über Zulässigkeitsgrenzen bei der Prüfung von Schweißnähten (Schweißverbindungen).
Wenn die Vertragspartner niedrigere Prüfkriterien verwenden, ist es möglich, dass die erreichte Güte deutlich niedriger ist als bei strikter Anwendung von diesem Dokument.

Essais non destructifs des assemblages soudés - Contrôle par radiographie - Partie 2: Techniques par rayons X ou gamma à l'aide de détecteurs numériques (ISO 17636-2:2022, Version corrigée 2023-02)

Le présent document spécifie les techniques de radiographie numérique permettant d'obtenir des résultats satisfaisants et reproductibles. Les techniques reposent sur une pratique généralement reconnue et sur la théorie fondamentale en la matière.
Le présent document s'applique au contrôle par radiographie numérique des assemblages soudés par fusion de matériaux métalliques. Il s'applique aux assemblages de plaques et de tubes. Outre sa signification conventionnelle, le terme « tube », tel qu'il est utilisé dans le présent document, couvre d'autres corps cylindriques, tels que tuyaux, conduites forcées, réservoirs de chaudières et appareils à pression.
Le présent document spécifie les exigences relatives au contrôle par radiographie numérique à rayons X et gamma des assemblages soudés de tubes métalliques pour la détection des imperfections, soit par radiographie numérique (CR), soit par radiographie avec des panneaux de détecteurs numériques (DDA). Il comprend un contrôle manuel et automatisé avec des DDA.
Les détecteurs numériques produisent une image numérique en valeurs de gris qui ne peut être visualisée et évaluée qu'à l'aide d'un ordinateur (Annexe E). Le présent document spécifie le mode opératoire recommandé pour le choix des détecteurs et la pratique radiographique. Le choix de l'ordinateur, du logiciel, de l'écran, de l'imprimante et des conditions d'observation est important, mais ne constitue pas le centre d'intérêt du présent document. Le mode opératoire spécifié dans le présent document fournit les exigences minimales pour la pratique radiographique permettant l'exposition et l'acquisition des radiogrammes numériques avec une sensibilité de détection des imperfections équivalente à celle de la radiographie à l'aide de film (spécifiée dans l'ISO 17636‑1).
Le présent document ne spécifie pas les niveaux d'acceptation des indications trouvées sur les radiogrammes numériques. L'ISO 10675 fournit des informations sur les niveaux d'acceptation pour le contrôle des soudures.
Si les parties contractantes appliquent des critères d'essai moins rigoureux, il se peut que la qualité obtenue soit nettement inférieure à celle atteinte par l'application stricte du présent document.

Neporušitveno preskušanje zvarnih spojev - Radiografsko preiskušanje - 2. del: Tehnike z rentgenskimi in gama žarki z uporabo digitalnih detektorjev (ISO 17636-2:2022)

Ta dokument določa tehnike digitalne radiografije z namenom omogočanja zadovoljivih in ponovljivih rezultatov. Tehnike so osnovane na splošno priznani praksi in temeljnem poznavanju subjekta.
Ta dokument se uporablja za digitalno radiografsko preskušanje talilno zvarjenih spojev v kovinskih materialih. Uporablja se za spoje plošč in cevi. Poleg svojega klasičnega pomena izraz »cev«, kot je uporabljen v tem dokumentu, zajema tudi druga cilindrična telesa, kot so dovodni kanali, bobni kotlov in tlačne posode.
Ta dokument določa zahteve za zaznavanje nepravilnosti zvarjenih spojev pri kovinskih ploščah in ceveh z digitalnim radiografskim preskušanjem z rentgenskimi ali gama žarki z uporabo računalniške radiografije (CR) ali radiografije z digitalnimi detektorskimi nizi (DDA). Vključuje ročni in avtomatizirani pregled z digitalnimi detektorskimi nizi.
Digitalni detektorji zagotavljajo digitalno sivinsko sliko, ki jo je mogoče prikazati in oceniti prek računalnika (dodatek E). Ta dokument določa priporočen postopek za izbiro detektorja in radiografsko prakso. Izbira računalnika, programske opreme, monitorja, tiskalnika in pogojev prikaza je pomembna, vendar ni ključni del tega dokumenta. Postopek, določen v tem dokumentu, zagotavlja minimalne zahteve za radiografsko prakso, ki omogočajo izpostavljenost in pridobivanje digitalnih rentgenskih slik z občutljivostjo zaznavanja nepravilnosti, enako kot pri radiografskem filmu (iz standarda ISO 17636-1).
Ta dokument ne določa stopenj sprejemljivosti za indikacije na digitalnih rentgenskih slikah. Standard ISO 10675 podaja informacije o stopnjah sprejemljivosti za pregled zvarnih spojev.
Če pogodbene stranke uporabijo nizka preskusna merila, bo dosežena kakovost morda znatno nižja od kakovosti, dosežene s strogim upoštevanjem tega dokumenta.

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Status
Published
Publication Date
04-Oct-2022
Technical Committee
Current Stage
6060 - Definitive text made available (DAV) - Publishing
Start Date
05-Oct-2022
Completion Date
05-Oct-2022

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Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 17636-2:2023
01-marec-2023
Nadomešča:
SIST EN ISO 17636-2:2013
Neporušitveno preskušanje zvarnih spojev - Radiografsko preiskušanje - 2. del:
Tehnike z rentgenskimi in gama žarki z uporabo digitalnih detektorjev (ISO 17636-
2:2022)
Non-destructive testing of welds - Radiographic testing - Part 2: X- and gamma-ray
techniques with digital detectors (ISO 17636-2:2022)
Zerstörungsfreie Prüfung von Schweißverbindungen - Durchstrahlungsprüfung - Teil 2:
Röntgen- und Gammastrahlungstechniken mit digitalen Detektoren (ISO 17636-2:2022)
Essais non destructifs des assemblages soudés - Contrôle par radiographie - Partie 2:
Techniques par rayons X ou gamma à l'aide de détecteurs numériques (ISO 17636-
2:2022)
Ta slovenski standard je istoveten z: EN ISO 17636-2:2022
ICS:
25.160.40 Varjeni spoji in vari Welded joints and welds
SIST EN ISO 17636-2:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 17636-2:2023

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SIST EN ISO 17636-2:2023


EN ISO 17636-2
EUROPEAN STANDARD

NORME EUROPÉENNE

October 2022
EUROPÄISCHE NORM
ICS 25.160.40 Supersedes EN ISO 17636-2:2013
English Version

Non-destructive testing of welds - Radiographic testing -
Part 2: X- and gamma-ray techniques with digital detectors
(ISO 17636-2:2022)
Essais non destructifs des assemblages soudés - Zerstörungsfreie Prüfung von Schweißverbindungen -
Contrôle par radiographie - Partie 2: Techniques par Durchstrahlungsprüfung - Teil 2: Röntgen- und
rayons X ou gamma à l'aide de détecteurs numériques Gammastrahlungstechniken mit digitalen Detektoren
(ISO 17636-2:2022) (ISO 17636-2:2022)
This European Standard was approved by CEN on 23 August 2022.

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
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 17636-2:2022 E
worldwide for CEN national Members.

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SIST EN ISO 17636-2:2023
EN ISO 17636-2:2022 (E)
Contents Page
European foreword . 3

2

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SIST EN ISO 17636-2:2023
EN ISO 17636-2:2022 (E)
European foreword
This document (EN ISO 17636-2:2022) 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 DIN.
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 April 2023, and conflicting national standards shall be
withdrawn at the latest by April 2023.
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 17636-2:2013.
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 17636-2:2022 has been approved by CEN as EN ISO 17636-2:2022 without any
modification.

3

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SIST EN ISO 17636-2:2023

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SIST EN ISO 17636-2:2023
INTERNATIONAL ISO
STANDARD 17636-2
Second edition
2022-09
Non-destructive testing of welds —
Radiographic testing —
Part 2:
X- and gamma-ray techniques with
digital detectors
Essais non destructifs des assemblages soudés — Contrôle par
radiographie —
Partie 2: Techniques par rayons X ou gamma à l'aide de détecteurs
numériques
Reference number
ISO 17636-2:2022(E)
© ISO 2022

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SIST EN ISO 17636-2:2023
ISO 17636-2:2022(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: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
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  © ISO 2022 – All rights reserved

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SIST EN ISO 17636-2:2023
ISO 17636-2:2022(E)
Contents Page
Foreword .v
1 S c op e . 1
2 Nor m at i ve r ef er enc e s . 1
3 Terms and definitions . 2
4 S ymbols and abbreviated terms.6
5 Classification of radiographic techniques and compensation principles .8
5.1 C lassification . 8
5.2 C ompensation principles, CP I, CP II or CP III . 8
5.2.1 G eneral . 8
5.2.2 C ompensation principle I (CP I) . 8
5.2.3 C ompensation principle II (CP II) . 8
5.2.4 C ompensation principle III (CP III) . 8
5 . 2 . 5 T he or e t ic a l b ac k g r ou nd . 9
6 General preparations and requirements . 9
6.1 Protection against ionizing radiation . 9
6.2 S urface preparation and stage of manufacture . 9
6.3 L ocation of the weld in the radiograph . 9
6.4 I dentification of radiographs . 9
6 . 5 M a rk i n g . 9
6.6 O verlap of digital images . 10
6.7 T ypes and positions of image quality indicators (IQIs) . 10
6.7.1 General . 10
6.7.2 Duplex wire IQIs. 10
6.7.3 Single wire or step-hole IQIs . 10
6.8 E valuation of image quality . 11
6.9 M inimum image quality values.12
6.10 Personnel qualification . 12
7 R e c om mende d t e c h n ique s .13
7.1 Te s t a r r a n g ement s . 13
7.1.1 G eneral .13
7.1.2 S ingle-wall penetration of plane objects (see Figure 1) . 14
7.1.3 S ingle-wall penetration of curved objects with the source outside the
object (see Figures 2 to 4) . 14
7.1.4 S ingle-wall penetration of curved objects with the source inside the object
for panoramic exposure (see Figures 5 to 7) . 15
7.1.5 Single-wall penetration of curved objects with the source located off-
centre and inside the object (see Figures 8 to 10) . 16
7.1.6 Double-wall penetration and double-image evaluation (DWDI) of pipes
with the elliptic technique and the source and the detector outside the
object (see Figure 11) . 17
7.1.7 Double-wall penetration and double-image evaluation (DWDI) with the
perpendicular technique and source and detector outside the object (see
Figure 12) . 17
7.1.8 D ouble-wall penetration and single-image evaluation (DWSI) of curved
objects for evaluation of the wall next to the detector (see Figures 13 to 16). 18
7.1.9 P enetration of objects with different material thicknesses (see Figure 17
to 19) . 19
7.2 C hoice of tube voltage and radiation source . 20
7.2.1 X -ray devices up to 1 000 kV . 20
7.2.2 O ther radiation sources . 21
7.3 D etector systems and metal screens . 22
7.3.1 Minimum normalized signal-to-noise ratio (SNR ) .22
N
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SIST EN ISO 17636-2:2023
ISO 17636-2:2022(E)
7.3.2 C ompensation principle II . 25
7.3.3 Metal screens for IPs and shielding . 25
7.4 A lignment of beam . 25
7.5 R eduction of scattered radiation . 26
7.5.1 Metal filters and collimators . 26
7.5.2 Interception of backscattered radiation . 26
7. 6 S ou r c e -t o-obje c t d is t a nc e .26
7.7 Geometric magnification technique . 33
7.8 M aximum area for a single exposure .34
7.9 P r o c e s s i n g .34
7.9.1 S can and read-out of images .34
7.9.2 C orrection of acquired DDA images . 35
7.9.3 B ad pixel interpolation . 35
7.9.4 I m a g e pr o c e s s i n g . 35
7.10 M onitor viewing conditions and storage of digital radiographs .36
8 Te s t r ep or t .36
Annex A (normative) Number of exposures for acceptable testing of a circumferential butt
weld .38
Annex B (normative) Minimum image quality values .43
Annex C (normative) Determination of basic spatial resolution .51
Annex D (informative) Determination of minimum grey values for CR practice .53
Annex E (informative) Grey values — General remarks .58
Annex F (informative) Considering the detector unsharpness for f .60
min
Annex G (informative) Calculation of recommended X-ray tube voltages from Figure 20 .63
Bibliography .64
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SIST EN ISO 17636-2:2023
ISO 17636-2:2022(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 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 second edition cancels and replaces the first edition (ISO 17636-2:2013), which has been technically
revised.
The main changes are as follows:
— the normative references have been updated;
— the figures have been updated;
— manual and automated inspection with DDAs has been considered in 6.6, 6.7, and 7.8;
— references to Figures 1 to 19 have been updated throughout the document;
— in 6.7 a), the acceptance of a wire visibility shorter than 10 mm for pipes with an external
diameter < 50 mm has been added;
— in 6.7.1, the use of ASTM wires and other IQIs by agreement of the contracting parties has been
added;
— 6.8, “Evaluation of image quality” for digital radiography has been added;
— in 6.9 and 7.2.2, the lower thickness limit for Se-75 applications has been deleted;
— in 6.8, 6.9 and 7.3.1, a clarification for the IQI usage for DWDI technique has been added;
— permission to reduce SNR if the tube voltage is reduced or energy-resolving detectors are used
N
to < 80 % of the values given in Figure 20 has been added in 7.3.1;
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© ISO 2022 – All rights reserved

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SIST EN ISO 17636-2:2023
ISO 17636-2:2022(E)
— in 7.3.2, the compensation principle II (CP II) has been extended to three wire pairs without the
agreement of the contracting parties;
— Annex C has been shortened to avoid duplication with ISO 19232-5;
— in D.2, a new note on fading has been added;
— a new Annex F has been added;
— a new Annex G has been added.
A list of all parts in the ISO 17636 series can be found on the ISO website.
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. Official
interpretations of ISO/TC 44 documents, where they exist, are available from this page:
https://committee.iso.org/sites/tc44/home/interpretation.html.
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SIST EN ISO 17636-2:2023
INTERNATIONAL STANDARD ISO 17636-2:2022(E)
Non-destructive testing of welds — Radiographic testing —
Part 2:
X- and gamma-ray techniques with digital detectors
1 S cope
This document specifies techniques of digital radiography with the object of enabling satisfactory and
repeatable results. The techniques are based on generally recognized practice and fundamental theory
of the subject.
This document applies to the digital radiographic testing of fusion welded joints in metallic materials.
It applies to the joints of plates and pipes. Besides its conventional meaning, “pipe”, as used in this
document, covers other cylindrical bodies such as tubes, penstocks, boiler drums and pressure vessels.
This document specifies the requirements for digital radiographic X- and gamma-ray testing by either
computed radiography (CR) or radiography with digital detector arrays (DDAs) of the welded joints
of metallic plates and tubes for the detection of imperfections. It includes manual and automated
inspection with DDAs.
Digital detectors provide a digital grey value image which can be viewed and evaluated using a
computer (Annex E). This document specifies the recommended procedure for detector selection and
radiographic practice. Selection of computer, software, monitor, printer and viewing conditions are
important, but are not the main focus of this document. The procedure specified in this document
provides the minimum requirements for radiographic practice which permits exposure and acquisition
of digital radiographs with equivalent sensitivity for the detection of imperfections as film radiography
(specified in ISO 17636-1).
This document does not specify acceptance levels for any of the indications found on the digital
radiographs. ISO 10675 provides information on acceptance levels for weld inspection.
If contracting parties apply lower test criteria, it is possible that the quality achieved will be significantly
lower than when this document is strictly applied.
2 Normat ive 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 5576, Non-destructive testing — Industrial X-ray and gamma-ray radiology — Vocabulary
ISO 9712, Non-destructive testing — Qualification and certification of NDT personnel
ISO 16371-1:2011, Non-destructive testing — Industrial computed radiography with storage phosphor
imaging plates — Part 1: Classification of systems
ISO 19232-1, Non-destructive testing — Image quality of radiographs — Part 1: Determination of the
image quality value using wire-type image quality indicators
ISO 19232-2, Non-destructive testing — Image quality of radiographs — Part 2: Determination of the
image quality value using step/hole-type image quality indicators
ISO 19232-4, Non-destructive testing — Image quality of radiographs — Part 4: Experimental evaluation
of image quality values and image quality tables
1
© ISO 2022 – All rights reserved

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SIST EN ISO 17636-2:2023
ISO 17636-2:2022(E)
ISO 19232-5, Non-destructive testing — Image quality of radiographs — Part 5: Determination of the
image unsharpness and basic spatial resolution value using duplex wire-type image quality indicators
EN 12543 (all parts), Non-destructive testing — Characteristics of focal spots in industrial X-ray systems
for use in non-destructive testing
EN 12679, Non-destructive testing — Radiographic testing — Determination of the size of industrial
radiographic gamma sources
ASTM E747, Standard Practice for Design, Manufacture and Material Grouping Classification of Wire Image
Quality Indicators (IQI) Used for Radiology
JIS Z2306, Radiographic image quality indicators for non-destructive testing
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 5576 and the following apply.
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
computed radiography
CR
complete system comprising a storage phosphor imaging plate (IP) (3.2) and a corresponding read-out
unit (scanner or reader), which converts the information from the IP into a digital image
3.2
storage phosphor imaging plate
IP
photostimulable luminescent material capable of storing a latent radiographic image of a material
being tested and which, upon stimulation by a source of red light of appropriate wavelength, generates
luminescence proportional to radiation absorbed
Note 1 to entry: When performing computed radiography (3.1), an IP is used in lieu of a film. When establishing
techniques related to source size (3.20) or focal geometries, the IP is referred to as a detector, i.e. source-to-
detector distance (3.21).
3.3
digital detector array
DDA
electronic device converting ionizing or penetrating radiation into a discrete array of analogue
signals which are subsequently digitized and transferred to a computer for display as a digital image
corresponding to the radiologic energy pattern imparted upon the input region of the device
3.4
structure noise
local sensitivity variations due to inhomogeneities in the sensitive layer (structure,
graininess) and surface of an imaging plate
Note 1 to entry: After scanning of the exposed imaging plate, the inhomogeneities appear as overlaid fixed
pattern noise in the digital image.
Note 2 to entry: This noise limits the maximum achievable image quality of digital CR images and can be
compared with the graininess in film images.
2
  © ISO 2022 – All rights reserved

---------------------- Page: 14 ----------------------
SIST EN ISO 17636-2:2023
ISO 17636-2:2022(E
...

SLOVENSKI STANDARD
oSIST prEN ISO 17636-2:2021
01-junij-2021
Neporušitveno preskušanje zvarnih spojev - Radiografske preiskave - 2. del:
Tehnike z rentgenskimi in gama žarki z uporabo digitalnih detektorjev (ISO/DIS
17636-2:2021)
Non-destructive testing of welds - Radiographic testing - Part 2: X- and gamma-ray
techniques with digital detectors (ISO/DIS 17636-2:2021)
Zerstörungsfreie Prüfung von Schweißverbindungen - Durchstrahlungsprüfung - Teil 2:
Röntgen- und Gammastrahlungstechniken mit digitalen Detektoren (ISO/DIS 17636-
2:2021)
Contrôle non destructif des assemblages soudés - Contrôle par radiographie - Partie 2:
Techniques par rayons X ou gamma à l'aide de détecteurs numériques (ISO/DIS 17636-
2:2021)
Ta slovenski standard je istoveten z: prEN ISO 17636-2
ICS:
25.160.40 Varjeni spoji in vari Welded joints and welds
oSIST prEN ISO 17636-2:2021 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
oSIST prEN ISO 17636-2:2021

---------------------- Page: 2 ----------------------
oSIST prEN ISO 17636-2:2021
DRAFT INTERNATIONAL STANDARD
ISO/DIS 17636-2
ISO/TC 44/SC 5 Secretariat: AFNOR
Voting begins on: Voting terminates on:
2021-05-05 2021-07-28
Non-destructive testing of welds — Radiographic testing —
Part 2:
X- and gamma-ray techniques with digital detectors
Contrôle non destructif des assemblages soudés — Contrôle par radiographie —
Partie 2: Techniques par rayons X ou gamma à l'aide de détecteurs numériques
ICS: 25.160.40
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 17636-2:2021(E)
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 SUPPORTING DOCUMENTATION. ISO 2021

---------------------- Page: 3 ----------------------
oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-2 :2021 (E)
ISO/DIS 17636-2:2021(E)

Contents Page
Foreword . v
Introduction . vii
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 2
4 Symbols and abbreviated terms . 6
5 Classification of radiographic techniques and compensation principles . 7
5.1 Classification. 7
5.2 Compensation principles, CP I, CP II or CP III . 7
6 General preparations and requirements . 8
6.1 Protection against ionizing radiation . 8
6.2 Surface preparation and stage of manufacture . 8
6.3 Location of the weld in the radiograph . 8
6.4 Identification of radiographs. 9
6.5 Marking . 9
6.6 Overlap of digital images . 9
6.7 Types and positions of image quality indicators . 9
6.7.1 General . 9
6.7.2 Duplex wire IQIs . 9
6.7.3 Single wire or step hole IQIs . 10
6.8 Evaluation of image quality. 11
6.9 Minimum image quality values . 11
6.10 Personnel qualification . 12
7 Recommended techniques for making digital radiographs . 12
7.1 Test arrangements . 12
7.1.1 General . 12
7.1.2 Radiation source located in front of the object and with the detector at the opposite
side (see Figure 1) . 13
7.1.3 Radiation source located outside the object and detector inside (see Figures 2 to 4) . 13
7.1.4 Radiation source centrally located inside the object and with the detector outside
(see Figures 5 to 7) . 15
7.1.5 Radiation source located off-centre inside the object and detector outside (see
Figures 8 to 10) . 16
7.1.6 Elliptic technique (see Figure 11) . 17
7.1.7 Perpendicular technique (see Figure 12) . 17
COPYRIGHT PROTECTED DOCUMENT
7.1.8 Radiation source located outside the object and detector on the other side
(see Figures 13 to 18) . 17
© ISO 2021
7.1.9 Technique for different material thicknesses (see Figure 19) . 19
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
7.2 Choice of tube voltage and radiation source . 19
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
7.2.1 X-ray devices up to 1 000 kV . 19
below or ISO’s member body in the country of the requester.
7.2.2 Other radiation sources . 21
ISO copyright office
7.3 Detector systems and metal screens . 22
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
© ISO 2021 – All rights reserved iii
Website: www.iso.org
Published in Switzerland

ii © ISO 2021 – All rights reserved

---------------------- Page: 4 ----------------------
oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-2 :2021 (E)
Contents Page
Foreword . v
Introduction . vii
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 2
4 Symbols and abbreviated terms . 6
5 Classification of radiographic techniques and compensation principles . 7
5.1 Classification. 7
5.2 Compensation principles, CP I, CP II or CP III . 7
6 General preparations and requirements . 8
6.1 Protection against ionizing radiation . 8
6.2 Surface preparation and stage of manufacture . 8
6.3 Location of the weld in the radiograph . 8
6.4 Identification of radiographs. 9
6.5 Marking . 9
6.6 Overlap of digital images . 9
6.7 Types and positions of image quality indicators . 9
6.7.1 General . 9
6.7.2 Duplex wire IQIs . 9
6.7.3 Single wire or step hole IQIs . 10
6.8 Evaluation of image quality. 11
6.9 Minimum image quality values . 11
6.10 Personnel qualification . 12
7 Recommended techniques for making digital radiographs . 12
7.1 Test arrangements . 12
7.1.1 General . 12
7.1.2 Radiation source located in front of the object and with the detector at the opposite
side (see Figure 1) . 13
7.1.3 Radiation source located outside the object and detector inside (see Figures 2 to 4) . 13
7.1.4 Radiation source centrally located inside the object and with the detector outside
(see Figures 5 to 7) . 15
7.1.5 Radiation source located off-centre inside the object and detector outside (see
Figures 8 to 10) . 16
7.1.6 Elliptic technique (see Figure 11) . 17
7.1.7 Perpendicular technique (see Figure 12) . 17
7.1.8 Radiation source located outside the object and detector on the other side
(see Figures 13 to 18) . 17
7.1.9 Technique for different material thicknesses (see Figure 19) . 19
7.2 Choice of tube voltage and radiation source . 19
7.2.1 X-ray devices up to 1 000 kV . 19
7.2.2 Other radiation sources . 21
7.3 Detector systems and metal screens . 22
© ISO 2021 – All rights reserved iii

---------------------- Page: 5 ----------------------
oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-2:2021(E)
7.3.1 Minimum normalized signal-to-noise ratio . 22
7.3.2 Compensation principle II . 25
7.3.3 Metal screens for IPs and shielding . 25
7.4 Alignment of beam . 26
7.5 Reduction of scattered radiation . 26
7.5.1 Metal filters and collimators. 26
7.5.2 Interception of backscattered radiation . 26
7.6 Source-to-object distance . 27
7.7 Geometric magnification technique . 33
7.8 Maximum area for a single exposure . 34
7.9 Processing . 34
7.9.1 Scan and read-out of images . 34
7.9.2 Correction of Acquired DDA Images . 35
7.9.3 Bad pixel interpolation. 35
7.9.4 Image processing. 35
7.10 Monitor viewing conditions and storage of digital radiographs . 36
8 Test report . 36
Annex A (normative) Number of exposures which give an acceptable examination of a
circumferential butt weld . 38
Annex B (normative) Minimum image quality values . 43
B.1 Single wall technique; IQI on source side . 43
B.2 Double wall technique; double image evaluation; IQI on source side . 45
B.3 Double wall technique: single or double image evaluation; IQI on detector side . 47
B.4 Unsharpness . 49
Annex C (normative) Determination of basic spatial resolution . 51
Annex D (normative) Determination of minimum grey values for CR practice. 53
D.1 Determination of SNR from SNR . 53
N measured
D.2 Determination of minimum grey values . 54
Annex E (informative) Grey values, general remarks. 58
E.1 Introduction . 58
E.2 Noise control . 58
Annex F (normative) Considering the detector unsharpness for f . 60
min
Annex G (informative) The maximum tube voltages of Figure 20 . 64
Bibliography . 65

iv © ISO 2021 – All rights reserved

---------------------- Page: 6 ----------------------
oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-2 :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 the 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 second edition cancels and replaces the first edition (ISO 17636-2:2013), which has been
technically revised.
The main changes compared to the previous edition are as follows:
 The normative references have been updated;
 The figures in this document have been updated;
 “Evaluation of image quality” for digital radiography has been added as 6.8;
 The lower thickness limit for Se-75 applications has been deleted in 6.9 and the “agreement of
contracting parties” has been deleted in 7.2.2;
 The permission of “class A” IQI visibility for “class B” testing with Se 75 in 6.9 for w < 10 mm has
been added;
 The references to Figure 1 to Figure 19 have been added in all relevant clauses;
 A clarification for IQI usage for DWDI technique has been added in 6.8, 6.9 and 7.3.1;
© ISO 2021 – All rights reserved v

---------------------- Page: 7 ----------------------
oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-2:2021(E)
 The permission to the reduce SNR , if the tube voltage is reduced to < 80% of the values as given in
N
Figure 20 in 7.3.1, has been added;
 The usage of ASTM wires and other IQIs by agreement of contracting parties in 6.7.1 has been
added;
 The compensation principle 2 (CP 2) was extended to 3 wire pairs without agreement of
contracting parties in 7.3.2;
 The annex C “Determination of basic spatial resolution” has been revised and partly deleted with
reference to ISO 19232-5;
 In annex D.2, a new note and recommendation on fading has been added;
 A new annex F “Considering the detector unsharpness for f ” has been added;
min
 A new annex G “The maximum tube voltages of Figure 20” has been added;
 The document has been editorially revised.
A list of all parts in the ISO 17636 series can be found on the ISO website.
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.
Official interpretations of ISO/TC 44 documents, where they exist, are available from this page:
https://committee.iso.org/sites/tc44/home/interpretation.html

vi © ISO 2021 – All rights reserved

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oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-2 :2021 (E)
Introduction
This document specifies fundamental techniques of radiography with the object of enabling satisfactory
and repeatable results. The techniques are based on generally recognized practice and fundamental
theory of the subject, inspection of fusion welded joints with digital radiographic detectors.
The procedure specified in this document provides the minimum requirements and practice which
permits exposure and acquisition of digital radiographs with equivalent sensitivity for detection of
imperfections as film radiography, specified in ISO 17636-1.
© ISO 2021 – All rights reserved vii

---------------------- Page: 9 ----------------------
oSIST prEN ISO 17636-2:2021

---------------------- Page: 10 ----------------------
oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-2 :2021 (E)
Non-destructive testing of welds – Radiographic testing – Part 2:
X- and gamma-ray techniques with digital detectors
1 Scope
This document specifies fundamental techniques of digital radiography with the object of enabling
satisfactory and repeatable results to be obtained economically. The techniques are based on generally
recognized practice and fundamental theory of the subject.
This document applies to the digital radiographic examination of fusion welded joints in metallic
materials. It applies to the joints of plates and pipes. Besides its conventional meaning, “pipe”, as used in
this document, covers other cylindrical bodies such as tubes, penstocks, boiler drums, and pressure
vessels.
[3]
NOTE This document complies with most requirements of ISO 16371-2.
This document specifies the requirements for digital radiographic X- and gamma-ray testing by either
computed radiography (CR) or radiography with digital detector arrays (DDA) of the welded joints of
metallic plates and tubes for the detection of imperfections.
Digital detectors provide a digital grey value (GV) image which can be viewed and evaluated using a
computer. This document specifies the recommended procedure for detector selection and
radiographic practice. Selection of computer, software, monitor, printer and viewing conditions are
important, but are not the main focus of this document. The procedure specified in this document
provides the minimum requirements for radiographic practice which permit exposure and acquisition
of digital radiographs with equivalent sensitivity for detection of imperfections as film radiography, as
specified in ISO 17636-1.
This document does not specify acceptance levels for any of the indications found on the digital
radiographs. ISO 10675 provides information on acceptance levels.
If contracting parties apply lower test criteria, it is possible that the quality achieved is significantly
lower than when this document is strictly applied.
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 5576, Non-destructive testing — Industrial X-ray and gamma-ray radiology — Vocabulary
ISO 9712, Non-destructive testing — Qualification and certification of NDT personnel
ISO 16371-1:2011, Non-destructive testing — Industrial computed radiography with storage phosphor
imaging plates — Part 1: Classification of systems
ISO 19232-1, Non-destructive testing — Image quality of radiographs — Part 1: Image quality indicators
(wire type) — Determination of image quality value
© ISO 2021 – All rights reserved 1

---------------------- Page: 11 ----------------------
oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-2:2021(E)
ISO 19232-2, Non-destructive testing — Image quality of radiographs — Part 2: Image quality indicators
(step/hole type) — Determination of image quality value
ISO 19232-4, Non-destructive testing — Image quality of radiographs — Part 4: Experimental evaluation
of image quality values and image quality tables
ISO 19232-5, Non-destructive testing — Image quality of radiographs — Part 5: Image quality indicators
(duplex wire type) — Determination of image unsharpness value
EN 12543 (all parts), Non-destructive testing — Characteristics of focal spots in industrial X-ray systems
for use in non-destructive testing
EN 12679, Non-destructive testing — Determination of the size of industrial radiographic source
...

SLOVENSKI STANDARD
oSIST prEN ISO 17636-2:2021
01-junij-2021
Neporušitveno preskušanje zvarnih spojev - Radiografske preiskave - 2. del:
Tehnike z rentgenskimi in gama žarki z uporabo digitalnih detektorjev (ISO/DIS
17636-1:2021)
Non-destructive testing of welds - Radiographic testing - Part 2: X- and gamma-ray
techniques with digital detectors (ISO/DIS 17636-1:2021)
Zerstörungsfreie Prüfung von Schweißverbindungen - Durchstrahlungsprüfung - Teil 2:
Röntgen- und Gammastrahlungstechniken mit digitalen Detektoren (ISO/DIS 17636-
1:2021)
Contrôle non destructif des assemblages soudés - Contrôle par radiographie - Partie 2:
Techniques par rayons X ou gamma à l'aide de détecteurs numériques (ISO/DIS 17636-
1:2021)
Ta slovenski standard je istoveten z: prEN ISO 17636-2 rev
ICS:
25.160.40 Varjeni spoji in vari Welded joints and welds
oSIST prEN ISO 17636-2:2021 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
oSIST prEN ISO 17636-2:2021

---------------------- Page: 2 ----------------------
oSIST prEN ISO 17636-2:2021
DRAFT INTERNATIONAL STANDARD
ISO/DIS 17636-1
ISO/TC 44/SC 5 Secretariat: AFNOR
Voting begins on: Voting terminates on:
2021-04-16 2021-07-09
Non-destructive testing of welds — Radiographic testing —
Part 1:
X- and gamma-ray techniques with film
Contrôle non destructif des assemblages soudés — Contrôle par radiographie —
Partie 1: Techniques par rayons X ou gamma à l'aide de film
ICS: 25.160.40
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 17636-1:2021(E)
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 SUPPORTING DOCUMENTATION. ISO 2021

---------------------- Page: 3 ----------------------
oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-1:2021(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: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2021 – All rights reserved

---------------------- Page: 4 ----------------------
oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-1:2021(E)

Contents Page
Foreword .v
Introduction .vii
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms . 3
5 Classification of radiographic techniques . 3
6 General preparations and requirements . 4
6.1 Protection against ionizing radiation . 4
6.2 Surface preparation and stage of manufacture . 4
6.3 Location of the weld in the radiograph . 4
6.4 Identification of radiographs . 4
6.5 Marking . 4
6.6 Overlap of films. 4
6.7 Types and positions of image quality indicators . 5
6.8 E valuation of image quality . 5
6.9 Minimum image quality values . 6
6.10 Personnel qualification . 6
7 Recommended techniques for making radiographs . 6
7.1 General . 6
7.2 Test arrangements . 7
7.2.1 General. 7
7.2.2 Radiation source located in front of the object and with the film at the
opposite side (see Figure 1) . 7
7.2.3 Radiation source located outside the object and film inside (see Figures 2 to 4) . 8
7.2.4 Radiation source centrally located inside the object and with the film
outside (see Figures 5 to 7) . 9
7.2.5 Radiation source located off-centre inside the object and film outside (see
Figures 8 to 10) . 9
7.2.6 Elliptical technique (see Figure 11) .10
7.2.7 Perpendicular technique (see Figure 12) .11
7.2.8 Radiation source located outside the object and film on the other side
(see Figures 13 to 18) .11
7.2.9 Technique for different material thicknesses (see Figure 19) .13
7.3 Choice of tube voltage and radiation source .13
7.3.1 X-ray devices up to 1 000 kV.13
7.3.2 Other radiation sources .14
7.3.3 Film systems and metal screens .15
7.4 Alignment of beam .17
7.5 Reduction of scattered radiation .17
7.5.1 Metal filters and collimators .17
7.5.2 Interception of backscattered radiation .17
7.6 Source-to-object distance .18
7.7 Maximum area for a single exposure .20
7.8 Density of radiograph .20
7.9 Processing .21
7.10 Film viewing conditions .21
8 Test report .21
Annex A (normative) Number of exposures which give an acceptable examination of a
circumferential butt weld .23
© ISO 2021 – All rights reserved iii

---------------------- Page: 5 ----------------------
oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-1:2021(E)

Annex B (normative) Minimum image quality values .28
Annex C (informative) The maximum tube voltages of Figure 20. .35
Bibliography .36
iv © ISO 2021 – All rights reserved

---------------------- Page: 6 ----------------------
oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-1:2021(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 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, in accordance with the Agreement
on technical cooperation between ISO and CEN (Vienna Agreement).
This second edition cancels and replaces ISO 17636-1:2013, which has been technically revised.
The main changes compared to the previous edition are as follows:
— the normative references have been updated;
— the figures have been updated;
— in 6.9 the lower thickness limit for Se-75 applications has been deleted;
— in 7.3.2 the lower thickness limit for Se-75 by agreement of contracting parties has been deleted;
— Update of references to the Figures 1 to 19 in the whole document;
— in 6.7 the usage of ASTM wires and other IQIs by agreement of contracting parties has been added;
— Clarification for measurement of optical density in the weld root;
— Clarification for IQI usage for DWDI technique;
— Addition of the acceptance of shorter wire visibility than 10 mm for pipes with an external diameter
< 50 mm in 6.7 a);
— the document has been editorial revised.
A list of all parts in the ISO 17636 series can be found on the ISO website.
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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oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-1:2021(E)

Official interpretations of ISO/TC 44 documents, where they exist, are available from this page: https://
committee .iso .org/ sites/ tc44/ home/ interpretation .html
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oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-1:2021(E)

Introduction
This document specifies fundamental techniques of radiography with the objective of enabling
satisfactory and repeatable results. The techniques are based on generally recognized practice and
fundamental theory of the subject, inspection of fusion welded joints with industrial radiographic films.
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oSIST prEN ISO 17636-2:2021
DRAFT INTERNATIONAL STANDARD ISO/DIS 17636-1:2021(E)
Non-destructive testing of welds — Radiographic testing —
Part 1:
X- and gamma-ray techniques with film
1 Scope
This document specifies techniques of radiographic examination of fusion welded joints in metallic
materials using industrial radiographic film techniques.
This document applies to the joints of plates and pipes. Besides its conventional meaning, “pipe” as used
in this document it covers other cylindrical bodies such as tubes, penstocks, boiler drums, and pressure
vessels.
[1]
NOTE This document complies with most requirements of ISO 5579 .
This document does not specify acceptance levels for any of the indications found on the radiographs.
If contracting parties apply lower test criteria, it is possible that the quality achieved is significantly
lower than when this document is strictly applied.
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 5576, Non-destructive testing — Industrial X-ray and gamma-ray radiology — Vocabulary
ISO 5580, Non-destructive testing — Industrial radiographic illuminators — Minimum requirements
ISO 9712, Non-destructive testing — Qualification and certification of NDT personnel
ISO 11699-1, Non-destructive testing — Industrial radiographic film — Part 1: Classification of film
systems for industrial radiography
ISO 11699-2, Non-destructive testing — Industrial radiographic films — Part 2: Control of film processing
by means of reference values
ISO 19232-1, Non-destructive testing — Image quality of radiographs — Part 1: Determination of the
image quality value using wire-type image quality indicators
ISO 19232-2, Non-destructive testing — Image quality of radiographs — Part 2: Determination of the
image quality value using step/hole-type image quality indicators
EN 12543 (all parts), Non-destructive testing — Characteristics of focal spots in industrial X-ray systems
for use in non-destructive testing
EN 12679, Non-destructive testing — Determination of the size of industrial radiographic sources —
Radiographic method
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 5576 and the following apply.
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oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-1:2021(E)

ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
nominal thickness
t
nominal thickness of the parent material only where manufacturing tolerances do not have to be taken
into account
3.2
penetration thickness change
Δt
change of penetrated thickness relative to the nominal thickness due to beam angle
3.3
penetrated thickness
w
thickness of material in the direction of the radiation beam calculated on the basis of the nominal
thicknesses of all penetrated walls
3.4
object-to-film distance
b
distance between the radiation side of the radiographed part of the test object and the film surface
measured along the central axis of the radiation beam
3.5
source size
d
size of the radiation source or focal spot size
Note 1 to entry: See EN 12679 or EN 12543.
3.6
source-to-film distance
SFD
distance between the source of radiation and the film measured in the direction of the beam
Note 1 to entry: SFD = f + b
where
f source-to-object distance
b object-to-film distance
3.7
source-to-object distance
f (SOD)
distance between the source of radiation and the source side of the test object measured along the
central axis of the radiation beam
3.8
external diameter
D
e
nominal external diameter of the pipe
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oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-1:2021(E)

3.9
Region of Interest
RoI
minimum area which should be visible on the radiograph and contains the weld and the heat affected
zone (HAZ) on both sides
3.10
Area of Interest
AoI
minimum area which should be visible on the radiograph and contains the weld, the heat affected zone
HAZ on both sides and all IQIs
4 Symbols and abbreviated terms
For the purposes of this document, the symbols given in Table 1 apply.
Table 1 — Symbols and terms
Symbol Term
b object-to-film distance
b′ object-to-film distance perpendicular to test object
D external diameter
e
d source size
f source-to-object distance
f′ source-to-object distance perpendicular to test object
f minimum source-to-object distance
min
t nominal thickness
Δt penetration thickness change
w penetrated thickness
F film
IQI image quality indicator
S radiation source
SFD source-to-film distance
NOTE Object-to-film distance (OFD) is equivalent to b.
Object-to-detector distance (ODD) as used in part 2 is equivalent to b.
The source-to-detector-distance (SDD) as used in digital radiography is equivalent to SFD.
The source-to-object distance (SOD) is equivalent to f.
5 Classification of radiographic techniques
The radiographic techniques are divided into two classes:
— Class A: basic techniques;
— Class B: improved techniques.
Class B techniques are used when class A might be insufficiently sensitive.
Radiographic techniques providing higher sensitivity than class B are possible and may be agreed
between the contracting parties by specification of all appropriate test parameters.
The choice of radiographic technique shall be agreed between the contracting parties.
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oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-1:2021(E)

If, for technical or industrial reasons, it is not possible to meet one of the conditions specified for class B,
such as the type of radiation source or the source-to-object distance, f, it may be agreed by contracting
parties that the condition selected may be that specified for class A. The loss of sensitivity shall be
compensated by an increase of minimum density to 3,0 or by selection of a better film system class with
a minimum density of 2,6. The other conditions for class B remain unchanged, especially the image
quality achieved (see Tables B.1 to B.12 and 6.9). Because of the better sensitivity compared to class A,
the test specimen may be regarded as being examined to class B. This does not apply if the special SFD
reductions as described in 7.7 for test arrangements 7.2.4 and 7.2.5 (Figures 5 to 10) are used.
6 General preparations and requirements
6.1 Protection against ionizing radiation
WARNING — Exposure of any part of the human body to X-rays or gamma-rays can be highly
injurious to health. Wherever X-ray equipment or radioactive sources are in use, appropriate
legal requirements shall be applied.
Local and/or national and/or international regulations and safety precautions when using ionizing
radiation shall be strictly applied.
6.2 Surface preparation and stage of manufacture
In general, surface preparation is not necessary, but where surface imperfections or coatings can cause
difficulty in detecting defects, the surface shall be ground smooth or the coatings shall be removed.
Unless otherwise specified, radiography shall be carried out after the final stage of manufacture, e.g.
after grinding or heat treatment.
6.3 Location of the weld in the radiograph
Where the radiograph does not show the weld, high density markers shall be placed on both sides of the
weld outside the region of interest (RoI).
6.4 Identification of radiographs
Symbols shall be affixed to each section of the object being radiographed. The images of these symbols
shall appear in the radiograph outside the region of interest (RoI) where possible and shall ensure
unambiguous identification of the section. Another identification system may be part of contract
agreement
6.5 Marking
Permanent markings on the object to be examined shall be made in order to accurately locate the
position of each radiograph (e.g. zero point, direction, identification, measure).
Where the nature of the material and/or its service conditions do not permit permanent marking, the
location may be recorded by means of accurate sketches or photographs.
6.6 Overlap of films
When radiographing an area with two or more separate films, the films shall overlap sufficiently to
ensure that the complete region of interest is radiographed. This shall be verified by a high density
marker on the surface of the object which is to appear on each film.
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oSIST prEN ISO 17636-2:2021
ISO/DIS 17636-1:2021(E)

6.7 Types and positions of image quality indicators
The quality of image shall be verified by use of image quality indicators (IQIs) in accordance with
ISO 19232-1 or ISO 19232-2. ASTM E 747 IQIs may be used if the material group of this document fits
better to the testing task. Tables for the conversion of wire numbers from the documemts ASTM E 747
and ISO 19232-1 can be found in both documents. By agreement between contracting parties, other
image quality indicators with the same radiographic attenuation as the test object and same dimensions
as defined in ISO 19232-1 or ISO 19232-2 may be used.
The IQI used shall be placed on the source side of the test object at the centre of the area of interest on
the parent metal beside the weld. The identification numbers and, when used, the lead letter F, shall not
be in the area of interest, except when geometric configuration makes it impractical. The IQI shall be in
close contact with the surface of the object.
Its location shall be made in a section of uniform thickness characterized by a uniform optical density
on the film.
According to the IQI type used, cases a) and b) shall be considered.
a) When using a wire IQI, the wires shall be directed perpendicular to the weld and its location shall
ensure that at least 10 mm of the wire length shows in a section of uniform optical density, which is
normally in the parent metal adjacent to the weld. For exposures in accordance with 7.2.6 and 7.2.7
(Figures 11 and 12), the IQI should be placed with the wires across the pipe axis and they should
not be projected into the image of the weld. The visible wire length can be shorter than 10 mm for
external pipe diameters smaller than 50 mm. The visible wire length shall be ≥ 20 % of the external
pipe diameter.
b) When using a step hole IQI, it shall be placed in such way that the hole number required is placed
close to the weld.
For single wall exposures in accordance with 7.2.4 and 7.2.5 (Figures 5 to 10), the IQI type used can be
placed either on the source side or on the film side. If the IQIs cannot be placed at the source side, the
IQIs are placed on the film side and the image quality shall be determined at least once from comparison
exposure with one IQI placed at the source side and one at the film side under the same conditions.
For double wall exposures in accordance with 7.2.6 and 7.2.7 (Figures 11 to 12) the IQI type used shall
be placed on the source side (use Tables B.5 to B.8). By agreement between contracting parties the IQI
may be placed on the film side (use Tables B.9 to B.12).
For double wall exposures in accordance with 7.2.8 (Figures 13 to 16), the IQI type used can be placed
on the film side. When the IQI is placed on the film side refer to the tables B.9 to B.12.
Where the IQIs are placed on the film side, the letter F shall be placed near the IQI and shall be visible in
the radiographic image and this shall be stated in the test report.
The identification numbers and, when used, the lead letter F, shall not be in the region of interest, except
when geometric configuration makes it impractical.
If steps have been taken to guarantee that radiographs of similar test objects and regions are produced
with identical exposure and processing techniques, and no differences in the image quality value
are likely, the image quality need not be verified for every radiograph. The extent of image quality
verification should be subject to agreement between the contracting parties.
For exposures of pipes with the source centrally located at least three IQIs should be placed equally
spaced at the circumference. The film(s) showing IQI images are then considered representative for the
whole circumference.
6.8 E valuation of image quality
The films shall be viewed in accordance with ISO 5580.
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