EN ISO 4126-2:2019

SLOVENSKI STANDARD
01-maj-2019
1DGRPHãþD
SIST EN ISO 4126-2:2003
SIST EN ISO 4126-2:2003/AC:2004
SIST EN ISO 4126-2:2003/AC:2007
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Safety devices for protection against excessive pressure - Part 2: Bursting disc safety
devices (ISO 4126-2:2018)
Sicherheitseinrichtungen gegen unzulässigen Überdruck - Teil 2:
Berstscheibeneinrichtungen (ISO 4126-2:2018)
Dispositifs de sécurité pour protection contre les pressions excessives - Partie 2:
Dispositifs de sûreté à disque de rupture (ISO 4126-2:2018)
Ta slovenski standard je istoveten z: EN ISO 4126-2:2019
ICS:
13.240 Varstvo pred previsokim Protection against excessive
tlakom pressure
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 4126-2
EUROPEAN STANDARD
NORME EUROPÉENNE
March 2019
EUROPÄISCHE NORM
ICS 13.240 Supersedes EN ISO 4126-2:2003
English Version
Safety devices for protection against excessive pressure -
Part 2: Bursting disc safety devices (ISO 4126-2:2018)
Dispositifs de sécurité pour protection contre les Sicherheitseinrichtungen gegen unzulässigen
pressions excessives - Partie 2: Dispositifs de sûreté à Überdruck - Teil 2: Berstscheibeneinrichtungen (ISO
disque de rupture (ISO 4126-2:2018) 4126-2:2018)
This European Standard was approved by CEN on 3 December 2018.

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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey 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
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 4126-2:2019 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Annex ZA (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive 2014/68/EU (PED) aimed to be covered . 4

European foreword
This document (EN ISO 4126-2:2019) has been prepared by Technical Committee ISO/TC 185 "Safety
devices for protection against excessive pressure" in collaboration with Technical Committee CEN/TC
69 “Industrial valves” 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 September 2019, and conflicting national standards
shall be withdrawn at the latest by September 2019.
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 4126-2:2003.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association, and supports essential requirements of EU Directive(s).
For the relationship with EU Directive(s) see informative Annex ZA, which is an integral part of this
document.
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, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Endorsement notice
The text of ISO 4126-2:2018 has been approved by CEN as EN ISO 4126-2:2019 without any
modification.
Annex ZA
(informative)
Relationship between this European Standard and the Essential
Requirements of EU Directive 2014/68/EU (PED) aimed to be covered
This European Standard has been prepared under a Commission’s standardization request to provide
one voluntary means of conforming to Essential Requirements of New Approach Directive 2014/68/EU,
Pressure Equipment Directive (PED).
Once this document is cited in the Official Journal of the European Union under that Directive,
compliance with the normative clauses of this document given in Table ZA.1 confers, within the limits of
the scope of this document, a presumption of conformity with the corresponding essential
requirements of that Directive and associated EFTA regulations.
Table ZA.1 — Correspondence between this European Standard and Annex I of the Directive
2014/68/EU
Essential Requirements of Clause(s)/sub-clause(s) Remarks/Notes
Directive 2014/68/EU of this EN
Clause 1.3 and 3.4 11 Protection against misuse and
instructions for the user
Clause 2.1 5, 6.1.2, 6.2, 7 to 10, 12 General design
Clause 2.2.2 6.1.1 Design for adequate strength
The experimental method limited to
PN x DN less than 3 000
Clause 2.3 6.1.2 Safe operation
Clause 2.6 4.3 Corrosion
Clause 3.1.2, paragraphs 2 11.3
Permanent joining
and 3
Clause 3.3 17 Marking and labelling
WARNING 1 — Presumption of conformity stays valid only as long as a reference to this European
Standard is maintained in the list published in the Official Journal of the European Union. Users of this
document should consult frequently the latest list published in the Official Journal of the European
Union.
WARNING 2 — Other Union legislation may be applicable to the product(s) falling within the scope of
this document.
INTERNATIONAL ISO
STANDARD 4126-2
Second edition
2018-12
Safety devices for protection against
excessive pressure —
Part 2:
Bursting disc safety devices
Dispositifs de sécurité pour protection contre les pressions
excessives —
Partie 2: Dispositifs de sûreté à disque de rupture
Reference number
ISO 4126-2:2018(E)
©
ISO 2018
ISO 4126-2:2018(E)
© 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
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Published in Switzerland
ii © ISO 2018 – All rights reserved

ISO 4126-2:2018(E)
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Materials . 4
4.1 Selection of materials . 4
4.2 Material specifications . 4
4.3 Protection from corrosion . 5
5 Types of bursting discs. 5
5.1 Conventional domed bursting discs (Forward acting) . 5
5.2 Reverse domed bursting discs (Reverse acting) . 6
5.3 Flat bursting discs . 6
5.4 Other types and designs . 8
6 Bursting disc holders . 8
6.1 Design . 8
6.1.1 Pressure-containing capability . 8
6.1.2 Other design requirements . 8
6.2 Types. 8
6.3 Connections .10
7 Back pressure supports .11
7.1 General .11
7.2 Opening back pressure supports .11
7.3 Non-opening back pressure supports .11
8 Temperature shields .11
9 Stiffening rings .11
10 Gaskets/seals .11
11 Assembly of bursting disc safety devices .11
11.1 General .11
11.2 Bursting disc safety devices with replaceable bursting disc assemblies .12
11.3 Bursting disc safety devices with non-replaceable bursting disc assemblies .12
12 Specified bursting pressure requirements .12
13 Inspection by the manufacturer .
...