SIST EN ISO 4126-2:2003

Safety devices for protection against excessive pressure - Part 2: Bursting disc safety devices (ISO 4126-2:2003)

This part of this Standard specifies the requirements for bursting disc safety devices. It includes the requirements for the design, manufacture, inspection, testing, certification, marking, and packaging. The requirements for the selection, application and installation of bursting disc safety devices are given in Part 6 of this standard.

Sicherheitseinrichtungen gegen unzulässigen Überdruck - Teil 2: Berstscheibeneinrichtungen (ISO 4126-2:2003)

Dieser Teil der Norm legt Anforderungen an Berstscheibeneinrichtungen fest. Er legt ferner die Anforderungen fest für Konstruktion, Herstellung, Überwachung, Prüfung, Bescheinigung, Kennzeichnung und Verpackung. Die Anforderungen für Auswahl, Anwendung und Anordnung von Berstscheibeneinrichtungen sind im Teil 6 dieser Norm enthalten.

Dispositifs de sécurité pour la protection contre les pressions excessives - Partie 2: Dispositifs de sureté a disque de rupture (ISO 4126-2:2003)

La présente norme spécifie les prescriptions des dispositifs de sureté a disque de rupture. Elle comprend les prescriptions de conception, de fabrication, de contrôle, d'essai, de marquage, de certification et de conditionnement. Les prescriptions concernant le choix, l'utilisation et l'installation des sécurités a disque de rupture sont indiquées dans la partie 6 de cette norme.

Naprave za varovanje pred visokim tlakom - 2. del: Naprave z razpočnimi membranami (ISO 4126-2:2003)

General Information

• Status: Withdrawn
• Publication Date: 30-Jun-2003
• Withdrawal Date: 07-Apr-2019
• ICS: 13.240 - Protection against excessive pressure
• Technical Committee: IHPV - Hydraulics and pneumatics
• Current Stage: 9900 - Withdrawal (Adopted Project)
• Start Date: 08-Apr-2019
• Due Date: 01-May-2019
• Completion Date: 08-Apr-2019
• 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: EN ISO 4126-2:2003 - Safety devices for protection against excessive pressure - Part 2: Bursting disc safety devices (ISO 4126-2:2003)

Relations

• Corrected By: SIST EN ISO 4126-2:2003/AC:2007 - Safety devices for protection against excessive pressure - Part 2: Bursting disc safety devices (ISO 4126-2:2003)
• Effective Date: 01-Jan-2007
• Corrected By: SIST EN ISO 4126-2:2003/AC:2004 - Safety devices for protection against excessive pressure - Part 2: Bursting disc safety devices (ISO 4126-2:2003)
• Effective Date: 01-Nov-2004
• Replaced By: SIST EN ISO 4126-2:2019 - Safety devices for protection against excessive pressure - Part 2: Bursting disc safety devices (ISO 4126-2:2018)
• Effective Date: 01-May-2019
• Corrected By: SIST EN ISO 4126-2:2003/AC:2007 - Safety devices for protection against excessive pressure - Part 2: Bursting disc safety devices (ISO 4126-2:2003)
• Effective Date: 08-Jun-2022
• Corrected By: SIST EN ISO 4126-2:2003/AC:2004 - Safety devices for protection against excessive pressure - Part 2: Bursting disc safety devices (ISO 4126-2:2003)
• Effective Date: 08-Jun-2022
• Replaced By: SIST EN ISO 4126-2:2019 - Safety devices for protection against excessive pressure - Part 2: Bursting disc safety devices (ISO 4126-2:2018)
• Effective Date: 08-Jun-2022
• Replaces: SIST ISO 6718:1998 - Bursting discs and bursting disc devices
• Effective Date: 01-Jul-2003

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 4126-2:2003
01-julij-2003
1DSUDYH]DYDURYDQMHSUHGYLVRNLPWODNRPGHO1DSUDYH]UD]SRþQLPL
PHPEUDQDPL,62
Safety devices for protection against excessive pressure - Part 2: Bursting disc safety
devices (ISO 4126-2:2003)
Sicherheitseinrichtungen gegen unzulässigen Überdruck - Teil 2:
Berstscheibeneinrichtungen (ISO 4126-2:2003)
Dispositifs de sécurité pour la protection contre les pressions excessives - Partie 2:
Dispositifs de sureté a disque de rupture (ISO 4126-2:2003)
Ta slovenski standard je istoveten z: EN ISO 4126-2:2003
ICS:
13.240 Varstvo pred previsokim Protection against excessive
tlakom pressure
SIST EN ISO 4126-2:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 4126-2:2003

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SIST EN ISO 4126-2:2003
EUROPEAN STANDARD
EN ISO 4126-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
January 2003
ICS 13.240
English version
Safety devices for protection against excessive pressure - Part
2: Bursting disc safety devices (ISO 4126-2:2003)
Dispositifs de sécurité pour la protection contre les Sicherheitseinrichtungen gegen unzulässigen Überdruck -
pressions excessives - Partie 2: Dispositifs de sûreté à Teil 2: Berstscheibeneinrichtungen (ISO 4126-2:2003)
disque de rupture (ISO 4126-2:2003)
This European Standard was approved by CEN on 9 September 2002.
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 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 Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, 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
© 2003 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 4126-2:2003 E
worldwide for CEN national Members.

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SIST EN ISO 4126-2:2003
EN ISO 4126-2:2003 (E)
Contents
page
Foreword.4
Introduction .5
1 Scope .5
2 Normative references .5
3 Terms and definitions.7
4 Materials.9
4.1 Selection of materials.9
4.2 Material specifications .10
4.3 Protection from corrosion.10
5 Types of bursting discs.10
5.1 Conventional domed bursting discs (forward acting) .10
5.2 Reverse domed bursting discs (reverse acting).11
5.3 Flat bursting discs .11
5.4 Other types and designs.13
6 Bursting disc holders .13
6.1 Design .13
6.2 Types.13
6.3 Connections .15
7 Back pressure supports.16
7.1 General.16
7.2 Opening back pressure supports.16
7.3 Non-opening back pressure supports.16
8 Temperature shields.16
9 Stiffening rings.16
10 Gaskets/seals .16
11 Assembly of bursting disc safety devices .16
11.1 General.16
11.2 Bursting disc safety devices with replaceable bursting disc assemblies.17
11.3 Bursting disc safety devices with non-replaceable bursting disc assemblies.17
12 Specified bursting pressure requirements .17
13 Inspection by the manufacturer .19
14 Test procedures .19
14.1 General.19
14.2 Pressure testing.19
14.3 Burst testing.19
14.4 Leak testing .21
14.5 Non-destructive examination.21
15 Certification .21
16 Product designation .22
17 Marking .22
17.1 General.22
17.2 Bursting discs/bursting disc assemblies.23
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17.3 Bursting disc holders.23
17.4 Bursting disc safety devices with non-replaceable bursting disc assemblies.24
17.5 Ancillary components .24
17.6 Omission of markings .24
18 Preparation for storage and transportation .25
18.1 General.25
18.2 Marking of packages .25
18.3 Provision of assembly and installation instructions .25
18.4 Provision of documents, loose identification plates etc. .25
Annex A (normative)  Materials .26
Annex B (informative)  Materials.28
Annex ZA (informative)  Clauses of this European Standard addressing essential requirements or
other provisions of EU Directives.33
Bibliography .34
3

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SIST EN ISO 4126-2:2003
EN ISO 4126-2:2003 (E)
Foreword
This document (EN ISO 4126-2:2003) has been prepared by Technical Committee CEN/TC 69 "Industrial valves",
the secretariat of which is held by AFNOR, in collaboration with ISO/TC 185 "Safety devices for protection against
excessive pressure".
This European Standard EN ISO 4126-2:2003 shall be given the status of a national standard, either by publication
of an identical text or by endorsement, at the latest by July 2003, and conflicting national standards shall be
withdrawn at the latest by July 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 relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this document.
This standard for safety devices for protection against excessive pressure consists of seven parts of which this is
Part 2. The various parts are:
 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 7 contains data that is common to more than one of the parts of this standard to avoid unnecessary repetition.
Annex A is normative. Annex B is informative.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal,
Slovakia, Spain, Sweden, Switzerland and the United Kingdom.
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SIST EN ISO 4126-2:2003
EN ISO 4126-2:2003 (E)
Introduction
A bursting disc safety device is a non-reclosing pressure relief device used to protect pressure equipment such as
pressure vessels, piping, gas cylinders or other enclosures from excessive pressure and/or excessive vacuum.
A bursting disc safety device typically comprises an assembly of components including a bursting disc, a bursting
disc holder and, where necessary, other components such as back pressure supports, stiffening rings etc.
The bursting disc is a pressure-containing and pressure-sensitive part of the bursting disc safety device and is
designed to open by bursting at a pre-determined pressure. There are many different types of bursting disc safety
devices manufactured in corrosion resistant materials, both metallic and non-metallic, to cover a wide range of
nominal sizes, burst pressures and temperatures.
1 Scope
This part of this European Standard specifies the requirements for bursting disc safety devices.
It includes the requirements for the design, manufacture, inspection, testing, certification, marking, and packaging.
The requirements for the application, selection and installation of bursting disc safety devices are given in Part 6 of
this European Standard.
2 Normative references
This European Standard incorporates by dated or undated reference, provisions from other publications. These
normative references are cited at the appropriate places in the text, and the publications are listed hereafter. For
dated references, subsequent amendments to or revisions of any of these publications apply to this European
Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the
publication referred to applies (including amendments).
EN 485-1, Aluminium and aluminium alloys – Sheet, strip and plate – Part 1: Technical conditions for inspection
and delivery.
EN 485-2, Aluminium and aluminium alloys – Sheet, strip and plate – Part 2: Mechanical Properties.
EN 485-3, Aluminium and aluminium alloys – Sheet, strip and plate – Part 3: Tolerances on shape and dimensions
for hot-rolled products.
EN 485-4, Aluminium and aluminium alloys – Sheet, strip and plate – Part 4: Tolerances on shape and dimensions
for cold-rolled products.
EN 573-3, Aluminium and aluminium alloys – Chemical composition and form of wrought products – Part 3:
Chemical composition.
EN 573-4, Aluminium and aluminium alloys – Chemical composition and form of wrought products – Part 4: Forms
of products.
EN 1092-1, Flanges and their joints - Circular flanges for pipes, valves, fittings and accessories, PN designated –
Part 1: Steel flanges.
EN 1333, Pipework components - Definition and selection of PN.
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SIST EN ISO 4126-2:2003
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EN 1652, Copper and copper alloys – Plate, sheet, strip and circles for general purposes.
EN 1653, Copper and copper alloys – Plate, sheet and circles for boilers, pressure vessels and hot water storage
units.
EN 10028-1, Flat products made of steels for pressure purposes – Part 1: General requirements.
EN 10028-7, Flat products made of steels for pressure purposes – Part 7: Stainless steels.
EN 10088-1, Stainless steels – Part 1: List of stainless steels.
EN 10095, Heat resisting steels and nickel alloys.
EN 10222-1, Steel forgings for pressure purposes – Part 1: General requirements for open die forgings.
EN ISO 6708, Pipework components - Definition and selection of DN (nominal size) (ISO 6708:1995).
DIN 17740, Wrought nickel – Chemical composition.
DIN 17742, Wrought nickel alloy with chromium – Chemical composition.
DIN 17743, Wrought nickel alloys with copper – Chemical composition.
DIN 17744, Wrought nickel alloys with molybdenum and chromium – Chemical composition.
DIN 17850, Titanium – Chemical composition.
SEW 400, Rolled and forged stainless steels.
BS 3072, Specification for nickel and nickel alloys – Sheet and plate.
BS 3073, Specification for nickel and nickel alloys – Strip.
ASTM A240/A240M, Standard specification for chromium and chromium-nickel stainless steel plate, sheet and strip
for pressure vessels and for general applications.
ASTM B127, Standard specification for nickel-copper alloy (UNS N04400) plate, sheet, and strip.
ASTM B162, Standard specification for nickel plate, sheet and strip.
ASTM B168, Standard specification for nickel-chromium-iron alloys (UNS N06600, N06601, N06603, N06690,
N06025, and N06045) and nickel-chromium-cobalt-molybdenum alloy (UNS N06617) plate, sheet and strip.
ASTM B209, Standard specification for aluminium and aluminium-alloy sheet and plate.
ASTM B265, Standard specification for titanium and titanium alloy strip, sheet and plate.
ASTM B333, Standard specification for nickel-molybdenum alloy plate, sheet and strip.
ASTM B424, Standard specification for Ni-Fe-Cr-Mo-Cu alloy (UNS N08825 and UNS N08221), plate, sheet and
strip.
ASTM B443, Standard specification for nickel-chromium-molybdenum-columbium alloy (UNS N06625) and nickel-
chromium-molybdenum-silicon alloy (UNS N06219), plate, sheet and strip.
ASTM B569, Standard specification for brass strip in narrow widths and light gauge for heat-exchanger tubing.
ASTM B575, Specification for low-carbon nickel-molybdenum-chromium, low-carbon nickel-chromium-
molybdenum, low-carbon nickel-chromium-molybdenum-copper, low-carbon nickel-chromium-molybdenum-
tantalum, low-carbon nickel-chromium-molybdenum-tungsten alloy plate, sheet and strip.
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SIST EN ISO 4126-2:2003
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ASTM B708, Standard specification for tantalum and tantalum alloy, plate, sheet and strip.
3 Terms and definitions
For the purposes of this European Standard, the following terms and definitions apply.
3.1
bursting disc safety device
non-reclosing pressure relief device actuated by differential pressure and designed to function by the bursting of
the bursting disc(s), and which is the complete assembly of installed components including, where appropriate, the
bursting disc holder
3.2
bursting disc assembly
complete assembly of components which are installed in the bursting disc holder to perform the desired function
3.3
bursting disc
pressure-containing and pressure-sensitive component of a bursting disc safety device
3.4
bursting disc holder
part of a bursting disc safety device which retains the bursting disc assembly in position
3.5
conventional domed bursting disc (also referred to as: forward-acting)
bursting disc which is domed in the direction of the bursting pressure (i.e. where the bursting pressure is applied to
the concave side of the bursting disc, see Figure 1)
3.6
slotted lined bursting disc
bursting disc made up of two or more layers, at least one of which is slit or slotted to control the bursting pressure
of the bursting disc
3.7
reverse domed bursting disc (also referred to as: reverse-acting)
bursting disc which is domed against the direction of the bursting pressure (i.e. where the bursting pressure is
applied to the convex side of the bursting disc, see Figure 2)
3.8
flat bursting disc
bursting disc having one or more layers which is flat when installed. It may be made of a ductile or brittle material
3.9
graphite bursting disc
bursting disc manufactured from graphite, impregnated graphite, flexible graphite or graphite composite and
designed to burst due to bending or shearing forces
NOTE The following definitions apply:
a) graphite. A crystalline form of the element carbon;
b) impregnated graphite. Graphite in which the open porosity is impregnated with a filler material;
c) flexible graphite. A graphite structure formed by the compression of thermally exfoliated graphite intercalation
compounds;
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d) graphite composite. Made up of two or more distinct materials and having different properties to those of the
separate materials and in which the proportion of graphite is over 50 per cent by weight.
3.10
bursting pressure
value of the differential pressure between the upstream side and the downstream side of the bursting disc when it
bursts
3.11
specified bursting pressure
bursting pressure quoted with a coincident temperature when defining the bursting disc requirements (used in
conjunction with a performance tolerance, see 3.15)
3.12
specified maximum bursting pressure
maximum bursting pressure quoted with a coincident temperature when defining the bursting disc requirements
(used in conjunction with specified minimum bursting pressure, see 3.13)
3.13
specified minimum bursting pressure
minimum bursting pressure quoted with a coincident temperature when defining the bursting disc requirements
(used in conjunction with specified maximum bursting pressure, see 3.12)
3.14
coincident temperature
temperature of the bursting disc associated with a burst pressure (see 3.11, 3.12 and 3.13) and which is the
expected temperature of the bursting disc when it is required to burst
3.15
performance tolerance
range of pressure between the specified minimum bursting pressure and the specified maximum bursting pressure,
or the range of pressure in positive and negative percentages or quantities which is related to the specified bursting
pressure (see Figure 9)
3.16
operating pressure
pressure existing at normal operating conditions within the system being protected
3.17
differential back pressure
differential pressure across a bursting disc in the opposite direction to the direction of the bursting pressure, which
is the result of pressure in the discharge system from other sources and/or a result of vacuum on the upstream side
of the bursting disc
3.18
vent area
cross-section area available for discharge of fluid
3.19
batch
quantity of bursting discs or bursting disc safety devices made as a single group of the same type, size, materials
and specified bursting pressure requirements where the bursting discs are manufactured from the same lot of
material (see 3.20)
3.20
lot of material
a) metal. Material of the same specification coming from the same heat number, heat treatment batch and
specified thickness with tolerances to an appropriate standard;
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b) graphite and flexible graphite. Material of the same specification grade and quality coming from the same
graphite manufacturer and the same manufacturing process;
c) impregnated graphite. Graphite of the same lot impregnated with a specific grade of filler material by the
same manufacturing process;
d) graphite composite. Graphite and specific grades of other constituents coming from the same mix
3.21
back pressure support
component of a bursting disc safety device which prevents damage to the bursting disc due to differential back
pressure
NOTE A back pressure support which is intended to prevent damage to the bursting disc when the system pressure falls
below atmospheric pressure is sometimes referred to as a vacuum support.
3.22
stiffening ring
component of a bursting disc assembly used primarily for reinforcing fragile bursting discs, so as to prevent
damage
3.23
coating
layer of metallic or non-metallic material applied to components of a bursting disc safety device by a coating
process
3.24
lining
additional sheet or sheets of metallic or non-metallic material forming part of a bursting disc assembly or bursting
disc holder
3.25
plating
metal layer applied to a bursting disc or bursting disc holder by a plating process
3.26
muffled outlet
component of a bursting disc safety device which disperses the discharge
3.27
temperature shield
device which protects a bursting disc from excessive temperature
4 Materials
4.1 Selection of materials
The selection of materials used for the components of bursting disc safety devices shall take into account:
a) suitability with regard to manufacture;
b) compatibility with the process fluid, the adjoining components and the chemical and physical conditions to
which the bursting disc safety device will be subjected when in service.
NOTE The use of corrosion-resistant materials for the downstream side of the bursting disc device is recommended
because corrosion of these parts can cause damage which can impair the performance of the bursting disc safety device.
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4.2 Material specifications
The material specification for the bursting disc safety devices shall be according to annex A (normative) and annex
B (informative).
They shall have uniform chemical and physical properties and shall be free from defects, which would cause the
bursting disc safety device to malfunction.
4.3 Protection from corrosion
Bursting disc safety devices are frequently required to operate in corrosive environments and, therefore,
components manufactured from materials affected by corrosion shall, where appropriate, be protected by coating,
plating or lining.
Coatings and plating shall be applied to give an even and homogeneous coating to the surfaces to be protected.
Linings shall be seamless and supplied with the bursting disc safety device so as to preserve them as a set or
integral unit.
The corrosion protection shall be supplied only by the manufacturer.
The corrosion protection shall not impair the performance of the bursting disc safety device.
5 Types of bursting discs
5.1 Conventional domed bursting discs (forward acting)
Conventional domed bursting discs shall be designed so that they burst due to tensile stresses when the bursting
pressure is applied to the concave side of the bursting disc (see Figure 1).
Key
1 Flat seat
2 Angle seat
3Flow
Figure 1 — Conventional domed bursting disc (forward acting)
They shall be domed by a means sufficient to cause a permanent set such that no further plastic flow will occur
initially when the bursting disc is subjected to its intended operating condition.
Conventional domed bursting discs include the following types:
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a) conventional simple domed. This type of bursting disc shall have one or more layers, the bursting pressure
of which is controlled by the ultimate tensile strength of the material(s);
b) conventional slotted domed. This type of bursting disc shall have two or more layers at least one of which
shall have slits or slots so as to reduce its strength and to control the bursting pressure;
c) conventional scored simple domed. This type of bursting disc shall be scored such that when the bursting
pressure is reached, the bursting disc opens along the score;
d) conventional simple domed with knife blades. This type of bursting disc shall open by being cut by the knife
blades when the bursting pressure is reached.
5.2 Reverse domed bursting discs (reverse acting)
Reverse domed bursting discs shall be designed to function due to buckling, bending or shearing stresses when
the bursting pressure is applied to the convex side of the bursting disc (see Figure 2).
Key
1Flow
Figure 2 — Reverse domed bursting disc (reverse acting)
Reverse domed bursting discs include the following types:
a) reverse domed scored. This type of bursting disc shall be scored such that, when the dome reverses at the
bursting pressure, the bursting disc opens along the score. The bursting disc may also have areas of
weakness which determine the pressure at which the bursting disc reverses;
b) reverse domed having slip or tear-away design. This type of bursting disc shall function by being expelled
downstream from the bursting disc holder;
NOTE A catching device can be provided for this type of bursting disc.
c) reverse domed with knife blades. This type of bursting disc shall open by being cut by knife blades during
reversal of the dome;
d) reverse domed that function by shearing. This type of bursting disc shall have one or more layers which
upon reversal opens due to shearing forces;
e) reverse domed composite or multi-layered. This type of bursting disc shall have two or more layers at least
one of which shall contain areas of weakness of such a configuration as to determine the pr
...