1、Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 21/07/2009 09:09, Uncontrolled Copy, (c) BSIg49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58P
2、art 3: Safety valves and bursting disc safety devices in combination (ISO 4126-3:2006)ICS 13.240Safety devices for protection against excessive pressure BRITISH STANDARDBS EN ISO 4126-3:2006BS EN ISO 4126-3:2006Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 21/07/2009 09:09, Uncontrolled Cop
3、y, (c) BSIThis British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 April 2009 BSI 2009ISBN 978 0 580 53523 9Amendments/corrigenda issued since publicationDate Commentscontract. Users are responsible for its correct application.Compliance with a Bri
4、tish Standard cannot confer immunity from legal obligations.National forewordThis British Standard is the UK implementation of EN ISO 4126-3:2006. The UK participation in its preparation was entrusted to Technical Committee PVE/12, Safety devices.A list of organizations represented on this committee
5、 can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 4126-3March 2006ICS 13.240English VersionSafety devices for protection against excessive pressure - Part3: Safety valves a
6、nd bursting disc safety devices in combination(ISO 4126-3:2006)Dispositifs de scurit pour protection contre les pressionsexcessives - Partie 3: Dispositifs de sret combinantsoupapes de sret et disques de rupture (ISO 4126-3:2006)Sicherheitseinrichtungen gegen unzulssigen berdruck -Teil 3: Sicherheit
7、sventile und Berstscheibeneinrichtungenin Kombination (ISO 4126-3:2006)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 EuropeanStandard the status of a national sta
8、ndard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards 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 la
9、nguage made by translationunder the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Ge
10、rmany, 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 STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGMa
11、nagement Centre: rue de Stassart, 36 B-1050 Brussels 2006 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 4126-3:2006: ELicensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 21/07/2009 09:09, Uncontrolled Copy, (c) BSIForeword T
12、his 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
13、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 Commis
14、sion 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 o
15、f 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, Slo
16、venia, Spain, Sweden, Switzerland and United Kingdom. BS EN ISO 4126-3:2006Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 21/07/2009 09:09, Uncontrolled Copy, (c) BSIiiiContents Page Introduction v 1 Scope . 1 2 Normative references . 1 3 Terms and definitions. 2 4 Symbols . 4 5 Design of co
17、mbination . 5 6 Installation of combination 5 7 Combination performance . 6 8 Determination of combination discharge capacity factor, Fd, by testing. 6 9 Derivation of combination discharge capacity factor, Fd. 9 10 Alternative to testing for Fd. 9 11 Certification of combination discharge capacity
18、factor, Fd. 10 12 Application and use of the certified combination discharge capacity factor, Fd10 13 Marking and identification of combination devices 10 14 Certification . 11 15 Preparation for storage and transport 11 BS EN ISO 4126-3:2006Requirements of EU Directive 97/23/EC (PED).12 Annex ZA (i
19、nformative) Relationship between this International Standard and the EssentialLicensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 21/07/2009 09:09, Uncontrolled Copy, (c) BSIiv Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
20、 (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,
21、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/
22、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 me
23、mber 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 (CE
24、N) 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 i
25、t 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: Pil
26、ot-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 con
27、tains data which is common to more than one of the parts of this standard to avoid unnecessary repetition. BS EN ISO 4126-3:2006Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 21/07/2009 09:09, Uncontrolled Copy, (c) BSIvIntroduction Bursting disc safety devices can be used in conjunction wit
28、h 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.
29、 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
30、to form the combination by a short length of pipe or a spool piece. BS EN ISO 4126-3:2006Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 21/07/2009 09:09, Uncontrolled Copy, (c) BSIblankLicensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 21/07/2009 09:09, Uncontrolled Copy, (c) BSI1Safety
31、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
32、) 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 v
33、essels, 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 si
34、zing 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 referenced document (including any amendments) applies. ISO 412
35、6-1:2004, Safety devices for protection against excessive pressure Part 1: Safety valves ISO 4126-2:2003, Safety devices for protection against excessive pressure Part 2: Bursting disc safety devices ISO 4126-4:2004, Safety devices for protection against excessive pressure Part 4: Pilot-operated saf
36、ety valves ISO 4126-5:2004, Safety devices for protection against excessive pressure Part 5: Controlled safety pressure relief systems (CSPRS) ISO 4126-6:2003, Safety devices for protection against excessive pressure Part 6: Application, selection and installation of bursting disc safety devices EN
37、764-7:2002, Pressure equipment Part 7: Safety systems for unfired pressure equipment EN 13480-1:2002, Metallic industrial piping Part 1: General EN 13480-2:2002, Metallic industrial piping Part 2: Materials EN 13480-3:2002, Metallic industrial piping Part 3: Design and calculation EN 13480-4:2002, M
38、etallic industrial piping Part 4: Fabrication and installation EN 13480-5:2002, Metallic industrial piping Part 5: Inspection and testing EN 13480-6:2002, Metallic industrial piping Part 6: Additional requirements for buried piping CEN/TR 13480-7:2002, Metallic industrial piping Part 7: Guidance on
39、the use of conformity assessment procedures BS EN ISO 4126-3:2006Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 21/07/2009 09:09, Uncontrolled Copy, (c) BSI2 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 combination installation whi
40、ch comprises a bursting disc safety device installed within five pipe diameters (from outlet of bursting disc holder to inlet of valve) before the inlet of a safety valve or a CSPRS See Figure 1. Key 1 safety valve or CSPRS 2 bursting disc safety device 3 safety valve or CSPRS inlet 4 bursting disc
41、safety device outlet NOTE Other bursting disc safety device configurations used in conjunction with safety valves or CSPRS are specified in ISO 4126-6. Figure 1 Diagram of combination showing relative distance 3.2 combination discharge capacity factor Fdfactor used to determine the discharge capacit
42、y of a safety valve or CSPRS when the safety valve or CSPRS is used in combination with a bursting disc safety device installed upstream of the safety valve or CSPRS 3.3 flow resistance factor Krfactor which determines the resistance to flow in a pipe work system caused by the presence therein of a
43、burst bursting disc, forming part of a bursting disc safety device, installed in the system NOTE Its symbol, Kr, is a dimensionless factor expressed as the velocity head loss. 3.4 bursting disc safety device non-reclosing pressure relief device actuated by differential pressure and designed to funct
44、ion by the bursting of the bursting disc(s) NOTE It is the complete assembly of installed components including, where appropriate, the bursting disc holder. BS EN ISO 4126-3:2006Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 21/07/2009 09:09, Uncontrolled Copy, (c) BSI33.5 bursting disc asse
45、mbly complete assembly of the components installed in the bursting disc holder to perform the desired function 3.6 bursting disc pressure-containing and pressure-sensitive component of a bursting disc safety device 3.7 bursting disc holder part of a bursting disc safety device that retains the burst
46、ing disc assembly in position 3.8 specified bursting pressure bursting pressure quoted with a coincident temperature when defining the bursting disc requirements NOTE It is used in conjunction with a performance tolerance (3.11). 3.9 specified maximum bursting pressure maximum bursting pressure quot
47、ed with the coincident temperature when defining the bursting disc requirements NOTE It is used in conjunction with a specified minimum bursting pressure (3.10). 3.10 specified minimum bursting pressure minimum bursting pressure quoted with the coincident temperature when defining the bursting disc
48、requirements NOTE It is used in conjunction with a specified maximum bursting pressure (3.9). 3.11 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 quan
49、tities which is related to the specified bursting pressure 3.12 operating pressure pressure existing at normal operating conditions within the system being protected 3.13 relieving pressure maximum pressure under discharge conditions in the pressurized system NOTE It may differ from the bursting pressure of the bursting disc. 3.14 bursting disc safety device discharge area minimum cross-sectional flow area of the bursting disc safety device, taking into consideration the possible reduction of the cross-section by, for example, bac
