EN ISO 4126-3:2006

Safety devices for protection against excessive pressure - Part 3: Safety valves and bursting disc safety devices in combination (ISO 4126-3:2006)

ISO 4126-3:2006 specifies the requirements for a product assembled from the in-series combination of safety valves or CSPRS (controlled safety pressure relief systems) according to ISO 4126-1, ISO 4126-4 and ISO 4126-5, and bursting disc safety devices according to ISO 4126-2 installed within no more than five pipe diameters from the valve inlet. It specifies the design, application and marking requirements for such products, which are used to protect pressure vessels, piping or other enclosures from excessive pressure, and which comprise the bursting disc safety device, a safety valve or CSPRS and, where applicable, a short length of connecting pipe or spool piece. In addition, it gives a method for establishing the combination discharge factor used in sizing combinations.

Sicherheitseinrichtungen gegen unzulässigen Überdruck - Teil 3: Sicherheitsventile und Berstscheibeneinrichtungen in Kombination (ISO 4126-3:2006)

Dieser Teil von ISO 4126 legt die Anforderungen fest an ein Produkt, bestehend aus einer in Reihe geschalteten Kombination von Sicherheitseinrichtungen bzw. gesteuerten Sicherheitsventilen (CSPRS) nach ISO 4126-1, ISO 4126-4 und ISO 4126-5 und Berstscheibeneinrichtungen nach ISO 4126 2, bei der die Berstscheibeneinrichtung in einem Abstand von höchstens 5 ´ Rohrdurchmesser vor der Ventileintrittsseite eingebaut ist. ISO 4126-3 legt die Anforderungen an die Konstruktion, Anwendung und Kennzeichnung von Produkten fest, die zum Schutz von Druckbehältern, Rohrleitungen oder anderen geschlossenen Systemen gegen unzulässigen Überdruck eingesetzt werden. Diese Produkte beinhalten die Berstscheibeneinrichtung, ein Sicherheitsventil oder CSPRS und gegebenenfalls ein kurzes Anschlussrohr- oder Leitungsstück. Zusätzlich wird ein Verfahren festgelegt, nach dem die bei der Bemessung der Kombination eingesetzte Ausflussziffer bestimmt wird.

Dispositifs de sécurité pour protection contre les pressions excessives - Partie 3: Dispositifs de sûreté combinant soupapes de sûreté et disques de rupture (ISO 4126-3:2006)

L'ISO 4126-3:2006 spécifie les exigences applicables aux combinaisons en série de soupapes de sûreté ou de DSDCS (dispositifs de sécurité à décharge contrôlés contre les surpression), conformément à l'ISO 4126-1, à l'ISO 4126-4 et à l'ISO 4126-5, et de dispositifs de sûreté à disque de rupture conformément à l'ISO 4126-2 installés à une distance de l'orifice d'entrée de la soupape au plus égale à cinq diamètres de tuyauterie. Elle spécifie les exigences de conception, d'application et de marquage de tels produits, qui sont utilisés pour protéger des récipients, des tuyauteries ou d'autres enceintes des pressions excessives, et qui comportent le dispositif de sûreté à disque de rupture, une soupape de sûreté ou un DSDCS et, le cas échéant, une courte longueur de tuyauterie ou une manchette de raccordement. Elle donne, en outre, la méthode permettant d'établir le coefficient de débit de la combinaison utilisé pour le dimensionnement des combinaisons.

Naprave za varovanje pred visokim tlakom - 3. del: Varnostni ventili in razpočne plošče v kombinaciji (ISO 4126-3:2006)

General Information

• Status: Withdrawn
• Publication Date: 28-Feb-2006
• Withdrawal Date: 29-Sep-2020
• ICS: 13.240 - Protection against excessive pressure
• Technical Committee: CEN/TC 69 - Industrial valves
• Drafting Committee: CEN/TC 69/WG 10 - Safety devices against excessive pressure
• Current Stage: 9960 - Withdrawal effective - Withdrawal
• Completion Date: 30-Sep-2020
• Directive: 2014/68/EU - Directive 2014/68/EU of the European Parliament and of the Council of 15 May 2014 on the harmonisation of the laws of the Member States relating to the making available on the market of pressure equipment
• Directive: 97/23/EC - Directive 97/23/EC of the European Parliament and of the Council of 29 May 1997 on the approximation of the laws of the Member States concerning pressure equipment
• Mandate: M/071 - Mandate to CEN for standardization in the field of Pressure equipment
• Ref Project: SIST EN ISO 4126-3:2006 - Safety devices for protection against excessive pressure - Part 3: Safety valves and bursting disc safety devices in combination (ISO 4126-3:2006)

Relations

• Replaced By: EN ISO 4126-3:2020 - Safety devices for protection against excessive pressure - Part 3: Safety valves and bursting disc safety devices in combination (ISO 4126-3:2020)
• Effective Date: 07-Oct-2020

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-2006
1DSUDYH]DYDURYDQMHSUHGYLVRNLPWODNRPGHO9DUQRVWQLYHQWLOLLQUD]SRþQH
SORãþHYNRPELQDFLML,62
Safety devices for protection against excessive pressure - Part 3: Safety valves and
bursting disc safety devices in combination (ISO 4126-3:2006)
Sicherheitseinrichtungen gegen unzulässigen Überdruck - Teil 3: Sicherheitsventile und
Berstscheibeneinrichtungen in Kombination (ISO 4126-3:2006)
Dispositifs de sécurité pour protection contre les pressions excessives - Partie 3:
Dispositifs de sureté combinant soupapes de sureté et disques de rupture (ISO 4126-
3:2006)
Ta slovenski standard je istoveten z: EN ISO 4126-3:2006
ICS:
13.240
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 4126-3
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2006
ICS 13.240
English Version
Safety devices for protection against excessive pressure - Part
3: Safety valves and bursting disc safety devices in combination
(ISO 4126-3:2006)
Dispositifs de sécurité pour protection contre les pressions Sicherheitseinrichtungen gegen unzulässigen Überdruck -
excessives - Partie 3: Dispositifs de sûreté combinant Teil 3: Sicherheitsventile und Berstscheibeneinrichtungen
soupapes de sûreté et disques de rupture (ISO 4126- in Kombination (ISO 4126-3:2006)
3:2006)
This European Standard was approved by CEN on 27 February 2006.
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 Central Secretariat 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 Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,
Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2006 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 4126-3:2006: E
worldwide for CEN national Members.

Foreword
This document (EN ISO 4126-3:2006) has been prepared by Technical Committee CEN/TC
69 "Industrial valves", the secretariat of which is held by AFNOR, in collaboration with
Technical Committee ISO/TC 185 "Safety devices for protection against excessive pressure".

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 2006, and conflicting
national standards shall be withdrawn at the latest by September 2006.

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 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,
Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary,
Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.

Annex ZA
(informative)
Relationship between this International Standard and the
Essential Requirements of EU Directive 97/23/EC (PED)

This European Standard has been prepared under a mandate given to CEN by the European
Commission and the European Free Trade Association to provide one means of conforming
to Essential Requirements of the New Approach Directive 97/23/EC, Pressure Equipment
Directive (PED).
Once this standard is cited in the Official Journal of the European Communities under that
Directive and has been implemented as a national standard in at least one Member State,
compliance with the normative clauses of this standard given in Table ZA.1 confers, within the
limits of the scope of this standard, a presumption of conformity with the corresponding
Essential Requirements of that Directive and associated EFTA regulations.

Table ZA.1 — Correspondence between this International Standard and Directive
97/23/EC (PED)
Sub-clauses of this EN Essential Requirements of Directive 97/23/EC (PED)
Essential Requirements Annex I of PED
5, 6, 7, 8, 9, 11 and 12 Safety accessories 2.11.1 and 2.11.2
5, 9 and 12 General design 2.1
5 Design for adequate strength 2.2
5, 6 and 7 Safe operation 2.3
8.1, 8.4, 8.5 and 8.6 Performance testing 2.2.4
13 Marking and labelling 3.3
WARNING — Other requirements and other EU Directives may be applicable to the
products falling within the scope of this standard.

INTERNATIONAL ISO
STANDARD 4126-3
First edition
2006-03-01
Safety devices for protection against
excessive pressure —
Part 3:
Safety valves and bursting disc safety
devices in combination
Dispositifs de sécurité pour protection contre les pressions
excessives —
Partie 3: Soupapes de sûreté et dispositifs de sûreté à disque de
rupture en combinaison
Reference number
ISO 4126-3:2006(E)
©
ISO 2006
ISO 4126-3:2006(E)
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ii © ISO 2006 – All rights reserved

ISO 4126-3:2006(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 2
4 Symbols . 4
5 Design of combination . 5
6 Installation of combination . 5
7 Combination performance . 6
8 Determination of combination discharge capacity factor, F , by testing. 6
d
9 Derivation of combination discharge capacity factor, F . 9
d
10 Alternative to testing for F . 9
d
11 Certification of combination discharge capacity factor, F . 10
d
12 Application and use of the certified combination discharge capacity factor, F . 10
d
13 Marking and identification of combination devices . 10
14 Certification . 11
15 Preparation for storage and transport. 11

ISO 4126-3:2006(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 4126-3 was prepared by the European Committee for Standardization (CEN) Technical Committee
CEN/TC 69, Industrial valves, ISO/TC 185, Safety devices for protection against excessive pressure, in
accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
This first edition of ISO 4126-3 cancels and replaces ISO 6718:1991, of which it constitutes a technical
revision.
ISO 4126 consists of the following parts, under the general title Safety devices for protection against
excessive pressure:
⎯ Part 1: Safety valves
⎯ Part 2: Bursting disc safety devices
⎯ Part 3: Safety valves and bursting disc safety devices in combination
⎯ Part 4: Pilot-operated safety valves
⎯ Part 5: Controlled safety pressure relief systems (CSPRS)
⎯ Part 6: Application, selection and installation of bursting disc safety devices
⎯ Part 7: Common data
⎯ Part 9: Application and installation of safety devices excluding stand-alone bursting disc safety devices
Part 7 contains data which is common to more than one of the parts of this standard to avoid unnecessary
repetition.
iv © ISO 2006 – All rights reserved

ISO 4126-3:2006(E)
Introduction
Bursting disc safety devices can be used in conjunction with safety valves in following cases:
a) to protect the safety valve against corrosion, fouling or operating conditions which could affect the safety
valve performance;
b) to prevent leakage;
c) to prevent total loss of contents from the protected equipment following the bursting of the bursting disc.
The term combination is used to describe the close-coupled (i.e. within 5 pipe diameters) assembly of a
bursting disc safety device with a safety valve or CSPRS, as defined by this part of ISO 4126. In some cases,
the bursting disc safety device and the safety valve or CSPRS are connected together to form the combination
by a short length of pipe or a spool piece.
INTERNATIONAL STANDARD ISO 4126-3:2006(E)

Safety devices for protection against excessive pressure —
Part 3:
Safety valves and bursting disc safety devices in combination
1 Scope
This part of ISO 4126 specifies the requirements for a product assembled from the in-series combination of
safety valves or CSPRS (controlled safety pressure relief systems) according to ISO 4126-1, ISO 4126-4 and
ISO 4126-5, and bursting disc safety devices according to ISO 4126-2 installed within no more than five pipe
diameters from the valve inlet. It specifies the design, application and marking requirements for such products,
which are used to protect pressure vessels, piping or other enclosures from excessive pressure, and which
comprise the bursting disc safety device, a safety valve or CSPRS and, where applicable, a short length of
connecting pipe or spool piece. In addition, it gives a method for establishing the combination discharge factor
used in sizing combinations.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referen
...