1、BS EN13648-1:2008ICS 13.240;23.020.40;23.060.40NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDCryogenic vessels Safety devices forprotection againstexcessive pressurePart 1: Safety valves for cryogenicserviceThis British Standardwas published under theauthority
2、 of the StandardsPolicy and StrategyCommittee on 28 February2009 BSI 2009ISBN 978 0 580 58011 6Amendments/corrigenda issued since publicationDate CommentsBS EN 13648-1:2008National forewordThis British Standard is the UK implementation of EN 13648-1:2008. Itsupersedes BS EN 13648-1:2002 which is wit
3、hdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee PVE/18, Cryogenic vessels.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisionsof a contract. Users
4、are responsible for its correct application.Compliance with a British Standard cannot confer immunityfrom legal obligations.BS EN 13648-1:2008EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 13648-1November 2008ICS 23.020.40; 23.060.40 Supersedes EN 13648-1:2002 English VersionCryogenic vessels - S
5、afety devices for protection againstexcessive pressure - Part 1: Safety valves for cryogenic serviceRcipients cryogniques - Dispositifs de protection contreles surpressions - Partie 1: Soupapes de sret pourservice cryogniqueKryo-Behlter - Sicherheitseinrichtungen gegenDruckberschreitung - Teil 1: Si
6、cherheitsventile fr denKryo-BetriebThis European Standard was approved by CEN on 5 October 2008.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 standard without any alteration. Up-to-da
7、te lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN 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 translationunder the
8、responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary,
9、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 NORMUNGManagement Centre: rue de
10、Stassart, 36 B-1050 Brussels 2008 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 13648-1:2008: EBS EN 13648-1:2008EN 13648-1:2008 (E) 2 Contents page Foreword3 1 Scope 4 2 Normative references 4 3 Terms and definitions .4 4 Requirem
11、ents.6 4.1 General6 4.2 Design .7 4.2.1 Design temperature .7 4.2.2 Drainage7 4.2.3 Stem guiding 7 4.2.4 Inserts .7 4.2.5 Sublimating cryogens .7 4.3 Materials .7 4.3.1 General7 4.3.2 Metallic materials.7 4.3.3 Corrosion resistance.7 4.3.4 Oxygen compatibility 8 4.3.5 Acetylene compatibility.8 4.3.6
12、 Non-metallic materials 8 5 Testing 8 5.1 Production testing .8 5.2 Type testing for cryogenic service 8 5.2.1 General8 5.2.2 Seat leakage test8 5.2.3 Cryogenic tests9 6 Determination of the certified derated coefficient of discharge (Kdr) 11 7 Cleanliness .11 8 Marking .12 Annex ZA (informative) Re
13、lationship between this European Standard and the Essential Requirements of EC Directive 97/23/EC (PED) 13 Bibliography 14 BS EN 13648-1:2008EN 13648-1:2008 (E) 3 Foreword This document (EN 13648-1:2008) has been prepared by Technical Committee CEN/TC 268 “Cryogenic vessels”, the secretariat of whic
14、h 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 May 2009, and conflicting national standards shall be withdrawn at the latest by May 2009. Attention is drawn to the possibility
15、 that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN 13648-1:2002. This document has been prepared under a mandate given to CEN by the European Comm
16、ission and the European Free Trade Association, and supports essential requirements of EC Directive(s) 97/23/EC. For relationship with EC Directive(s), see informative Annex ZA, which is an integral part of this document. This European Standard is composed of the following Parts: EN 13648-1, Cryogen
17、ic vessels Safety devices for protection against excessive pressure Part 1: Safety valves for cryogenic service; EN 13648-2, Cryogenic vessels Safety devices for protection against excessive pressure Part 2: Bursting disc safety devices for cryogenic service; EN 13648-3, Cryogenic vessels Safety dev
18、ices for protection against excessive pressure Part 3: Determination of required discharge Capacity and sizing. 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
19、, 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 the United Kingdom. BS EN 13648-1:2008EN 13648-1:20
20、08 (E) 4 1 Scope This European Standard specifies the requirements for the design, manufacture and testing of safety valves for cryogenic service, that is to say for operation with cryogenic fluids (as defined in EN 1251-1) below 10 C in addition to operation at ambient temperature. It is a requirem
21、ent of this European Standard that the valves comply with EN ISO 4126-1 or EN ISO 4126-4. In the event of different requirements, the requirements for cryogenic service are applied. NOTE 1 A cryogenic fluid (refrigerated liquefied gas) is a gas which is partially liquid because of its low temperatur
22、e (including totally evaporated liquids and supercritical fluids). This European Standard is restricted to valves not exceeding a size of DN 100 for category B. The valves of category A are limited to DN 25 and set pressures up to 40 bars. Both categories are designed to relieve single phase vapours
23、 or gases. A valve can be specified, constructed and tested such that it is suitable for use with more than one gas or with mixtures of gases. NOTE 2 All safety valves covered in this European Standard correspond to category IV of PED (Directive 97/23/EC) and category 3 of TPED (Directive 99/36/EC).
24、 NOTE 3 This European Standard does not provide methods for determining the capacity of relief valve(s) for a particular cryogenic vessel. Such methods are provided in EN 13648-3. 2 Normative references The following referenced documents are indispensable for the application of this document. For da
25、ted references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 1252-1, Cryogenic vessels Materials Part 1: Toughness requirements for temperatures below -80C EN 1252-2, Cryogenic vessels Materials Part 2: T
26、oughness requirements for temperatures between -80C and -20C EN 1797, Cryogenic vessels Gas/material compatibility EN 12300, Cryogenic vessels Cleanliness for cryogenic service EN ISO 4126-1:2004, Safety devices for protection against excessive pressure Part 1: Safety valves (ISO 4126-1:2004) EN ISO
27、 4126-4:2004, Safety devices for protection against excessive pressure Part 4: Pilot operated safety valves (ISO 4126-4:2004) 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 DN (nominal size) alphanumeric designation of size for components of
28、 a pipework system, which is used for reference purposes and which comprises the letters DN followed by a dimensionless whole number that is indirectly related to the physical size, in millimetres, of the bore or outside diameter of the end connections adapted from EN ISO 6708:1995 3.2 pressure gaug
29、e pressure that is the value which is equal to the algebraic difference between the absolute pressure and the atmospheric pressure BS EN 13648-1:2008EN 13648-1:2008 (E) 5 3.3 specified minimum temperature lowest temperature for which the safety valve is specified 3.4 safety valve category A safety v
30、alve which might be expected to relieve periodically during operation of the cryogenic vessel due to the absence of an alternative relieving or control device EXAMPLE A pressure regulating vent valve designed for frequent operation. 3.5 safety valve category B safety valve which would not be expecte
31、d to relieve during normal operation due to the provision of an alternative relieving or control device 3.6 cryogenic fluid gas which is partially liquid because of its low temperature NOTE The cryogenic fluids include evaporated liquids and supercritical fluids. The refrigerated but non-toxic gases
32、 given in Table 1 and mixtures of them are referred to as cryogenic fluids. BS EN 13648-1:2008EN 13648-1:2008 (E) 6 Table 1: Refrigerated but non-toxic gases Item and group Identification number, name and description a3 A Asphyxiant gases 1913 Neon, refrigerated liquid 1951 Argon, refrigerated liqui
33、d 1963 Helium, refrigerated liquid 1970 Krypton, refrigerated liquid 1977 Nitrogen , refrigerated liquid 2187 Carbon dioxide, refrigerated liquid 2591 Xenon, refrigerated liquid 3136 Trifluoromethane, refrigerated liquid 3158 Gas, refrigerated liquid, N.O.S. b3 O Oxidizing gases 1003 Air, refrigerat
34、ed liquid 1073 Oxygen, refrigerated liquid 2201 Nitrous oxide, refrigerated liquid, oxidizing 3311 Gas, refrigerated liquid, oxidizing, N.O.S b.3 F Flammable gases 1038 Ethylene, refrigerated liquid 1961 Ethane, refrigerated liquid 1966 Hydrogen, refrigerated liquid 1972 Methane, refrigerated liquid
35、 or natural gas, refrigerated liquid, with high methane content 3138 Ethylene, acetylene and propylene mixture, refrigerated liquid, containing at least 71,5 % ethylene with not more than 22,5 % acetylene and not more than 6 % propylene 3312 Gas, refrigerated liquid, flammable, N.O.S ba Item and gro
36、up, identification number, name and description according to the United Nations. b N.O.S. = not otherwise specified. 3.7 relieving pressure pressure used for the sizing of a safety valve which is greater than or equal to the set pressure plus overpressure NOTE For set pressure and overpressure defin
37、itions see EN ISO 4126-1. 4 Requirements 4.1 General The valve shall satisfy all the requirements of EN ISO 4126-1 or EN ISO 4126-4 except in cases where these Standards include diverging requirements, then this European Standard shall be applied. BS EN 13648-1:2008EN 13648-1:2008 (E) 7 4.2 Design 4
38、.2.1 Design temperature The valve shall be suitable for operation at all temperatures between the specified minimum temperature and + 65 C. 4.2.2 Drainage The design of the valve or its installation shall be such as to avoid accumulation of water within it, even when the specified outlet connection
39、is fitted. 4.2.3 Stem guiding The design of guiding shall avoid malfunction of the valve due to deposition and freezing of atmospheric moisture on and within the valve during normal operation. The valve shall be sufficiently robust such that the effectiveness of the guiding cannot be defeated by nor
40、mal handling. 4.2.4 Inserts Where soft disc inserts are used to ensure leak tight shut off (see 5.2.2), the design shall be such as to prevent cold flow of the insert to a degree that results in the valve failing to operate correctly. 4.2.5 Sublimating cryogens Where the valve is specified as suitab
41、le for service with products that, when vented to atmosphere from any pressure between the valves relieving pressure and re-seating pressure and at any temperature within the valves specified operating temperature range, condense from gas or vapour directly to solid, for example CO2, the design shal
42、l be such as to avoid the valve failing to operate correctly due to deposition of solid product within the valve body or its outlet. 4.3 Materials 4.3.1 General This clause indicates important material properties for safe use of safety valves (prevention of embrittlement, gas compatibility, etc.). N
43、OTE It does not address all the PED essential requirements relevant to materials (in particular no recommended materials are listed). Materials that may come into contact with the process fluid during operation shall be compatible with the process fluid. The materials of all components shall have me
44、chanical properties suitable for their minimum operating temperatures. 4.3.2 Metallic materials Metallic materials shall be in conformance with EN 1252-1or EN 1252-2 as appropriate to the specified minimum temperature. 4.3.3 Corrosion resistance In addition to resistance to normal atmospheric corros
45、ion (or adequate protection), particular care shall be taken to ensure that the valve cannot be rendered inoperative by accumulation of corrosion products. Some copper alloys are susceptible to stress corrosion cracking, consequently careful consideration shall be given before selection of these mat
46、erials for components under stress. BS EN 13648-1:2008EN 13648-1:2008 (E) 8 4.3.4 Oxygen compatibility If the specified minimum temperature is equal to or below the boiling point of air (approximately 190 C at atmospheric pressure) or the valve is intended for service with oxygen or oxidising produc
47、ts, the materials shall be oxygen compatible in accordance with EN 1797. 4.3.5 Acetylene compatibility Metallic materials shall contain less than 70 % copper if specified for use with mixtures containing acetylene. 4.3.6 Non-metallic materials Non-metallic materials are, so far, well established onl
48、y for use on the disc or seat to provide leak tightness across the seat when the valve is closed. If such materials are to be used for structural parts, they shall have properties appropriate to the application and at least meet the requirements of 4.3.2. Non-metallic materials shall also: have mech
49、anical properties that will allow the valve to pass the type testing defined in 5.2 ; be oxygen compatible if relevant (see 4.3.4 above). 5 Testing 5.1 Production testing It shall be performed in accordance with the requirements of EN ISO 4126-1 or EN ISO 4126-4. Where a pressure test is required the test medium shall be clean water for hydraulic tests or oil free air or an inert gas such as nitrogen for pneumatic tests. 5.2 Type testing for cryogenic service 5.2.1 General The safety valves model shall have been tested
