BS EN 1626-1999 制冷容器.制冷用阀门.pdf

| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS EN 16261999 The European Standard EN 16261999 has the status of a British Standard ICS 23.060.20 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Cryogenic vessels Valves for cryogenic service Licensed Copy Institute of Technology Tallaght, Institute of Technology, Fri Nov 09 102949 GMT0000 2007, Uncontrolled Copy, c BSI This British Standard, having been prepared under the direction of the Engineering Sector Committee, was published under the authority of the Standards Committee and comes into effect on 15 August 1999  BSI 08-1999 ISBN 0 580 32362 5 BS EN 16261999 Amendments issued since publication Amd. No.DateComments National foreword This British Standard is the English language version of EN 16261999. The UK participation in its preparation was entrusted to Technical Committee PVE/18, Cryogenic vessels, which has the responsibility to aid enquirers to understand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests ined; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled International Standards Correspondence Index, or by using the Find facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 8, an inside back cover and a back cover. The BSI copyright notice displayed throughout this document indicates when the document was last issued. Licensed Copy Institute of Technology Tallaght, Institute of Technology, Fri Nov 09 102949 GMT0000 2007, Uncontrolled Copy, c BSI CEN European Committee for Standardization Comite Europe en de Normalisation Europa isches Komitee fu r Normung Central Secretariat rue de Stassart 36, B-1050 Brussels  1999 CEN All rights of exploitation in any and by any means reserved worldwide for CEN national Members. Ref. No. EN 16261999 E EUROPEAN STANDARDEN 1626 NORME EUROPE ENNE EUROPA ISCHE NORM March 1999 ICS 23.020.40; 23.060.20 Descriptors English version Cryogenic vessels Valves for cryogenic service Re cipients cryoge niques Robinets pour usage cryoge nique Kryo-Beha lter Absperrarmaturen fu r tiefkalten Betrieb This European Standard was approved by CEN on 3 March 1999. 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, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. Licensed Copy Institute of Technology Tallaght, Institute of Technology, Fri Nov 09 102949 GMT0000 2007, Uncontrolled Copy, c BSI Page 2 EN 16261999  BSI 08-1999 Foreword This European Standard has been prepared by Technical Committee CEN/TC 268, Cryogenic vessels, 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 1999, and conflicting national standards shall be withdrawn at the latest by September 1999. This European Standard 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 Directives. For relationship with EU Directives, see inative annex ZA, which is an integral part of this standard. This document also supports the objectives of the framework Directives on Transport of Dangerous Goods. This standard has been ted for reference into the RID and/or the technical anns of the ADR. Therefore, the standards listed in the normative references and covering basic requirements of the RID/ADR not addressed within the present document are normative only when the standards themselves are referred to in the RID and/or in the technical anns of the ADR. 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, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Contents Page Foreword2 1Scope3 2Normative references3 3Definitions3 4Requirements3 4.1Materials3 4.2Design4 5Testing4 5.1Production tests4 5.2Sample valve tests4 6Cleanliness5 7Marking5 Annex A inative Recommended s for leak-tightness testing of cryogenic valves6 Annex ZA inative Clauses of this European Standard addressing essential requirements or other provisions of EU Directives8 Licensed Copy Institute of Technology Tallaght, Institute of Technology, Fri Nov 09 102949 GMT0000 2007, Uncontrolled Copy, c BSI w w w . b z f x w . c o m Page 3 EN 16261999  BSI 08-1999 1 Scope This standard specifies the requirements for the design, manufacture and testing of valves for cryogenic service, i.e. for operation with cryogenic fluids as defined in prEN 1251-11995 below 210 8C as well as at ambient conditions, to allow for start-up and run-down. It specifies additional requirements for cryogenic service for the appropriate valve product standard. It applies to sizes up to DN 150 and vacuum-jacketed cryogenic valves. This standard is not applicable to safety valves and valves for liquefied natural gas LNG. It is intended that the valve be designed and tested to satisfy the generally accepted nominal pressure, e.g. PN 40. Valves may then be selected with a PN equal to or greater than the maximum allowable pressure PS of the equipment with which they are to be used. 2 Normative references This European Standard incorporates, by dated or undated reference, provisions from other publications. These normative references are cited at 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. prEN 191996, Industrial valves Marking. prEN 1251-11995, Cryogenic vessels Transportable vacuum-insulated of not more than 1 000 litres volume Part 1 Fundamental requirements. EN 1252-1, Cryogenic vessels Materials Part 1 Toughness requirements for temperatures below 280 8C. EN 1333, Pipework components Definition and selection of PN. prEN 1503-11994, Valves Shell materials Part 1 Steels. prEN 1503-21994, Valves Shell materials Part 2 ISO steels. prEN 1503-31994, Valves Shell materials Part 3 Cast iron. prEN 1503-41997, Valves Shell materials Part 4 Copper alloys specified in European Standards. EN 1797-1, Cryogenic vessels Gas/material compatibility Part 1 Oxygen compatibility. EN 12300, Cryogenic vessels Cleanliness for cryogenic service. EN ISO 6708, Pipework components Definition and selection of DN nominal size ISO 67081995. ISO 5208, Industrial valves Pressure testing of valves. 3 Definitions For the purposes of this standard, the following definitions apply. 3.1 nominal size DN is defined in accordance with EN ISO 6708 3.2 nominal pressure PN is defined in accordance with EN 1333 3.3 specified minimum temperature the lowest temperature for which the valve is specified 3.4 valve category A valves intended to be operated with normal frequency above 20 cycles a year 3.5 valve category B valves intended to be operated only occasionally, i.e. with a frequency below 20 cycles a year 4 Requirements 4.1 Materials 4.1.1 Metallic materials Metallic materials to be used in the construction of cryogenic valves shall be suitable for general valve uses as defined in prEN 1503-11994, prEN 1503-21994, prEN 1503-31994 and prEN 1503-41997. In addition, the following requirements apply. 4.1.1.1 Toughness requirements Materials which exhibit a ductile/brittle transition shall have the minimum impact test values specified in EN 1252-1. These requirements apply only to the valve parts exposed to critical temperatures and not to control elements, for example. Non-ferrous materials which can be shown to have no ductile/brittle transition do not require additional impact tests. 4.1.1.2 Corrosion resistance Materials shall be resistant to normal atmospheric corrosion and to the medium handled. 4.1.1.3 Oxygen compatibility If the specified minimum temperature is equal to or below the boiling point of air, or the valve is intended for oxygen service, the materials which are, or likely to be, in contact with oxygen or an oxygen-enriched air shall be oxygen-compatible in accordance with EN 1797-1. 4.1.1.4 Flammable gas compatibility For hydrogen service, see relevant standards. Copper alloys containing more than 70 of copper shall not be used for fluids containing acetylene. Licensed Copy Institute of Technology Tallaght, Institute of Technology, Fri Nov 09 102949 GMT0000 2007, Uncontrolled Copy, c BSI w w w . b z f x w . c o m Page 4 EN 16261999  BSI 08-1999 4.1.2 Non-metallic materials Non-metallic materials to be used in packing and glands shall have mechanical properties which will allow the valves to pass the sample valve test for category A valves as defined in this standard see 5.2; be oxygen-compatible as defined in 4.1.1.3. If non-metallic materials are used for structural parts, their suitability shall be proven. 4.2 Design 4.2.1 General The valves shall fulfil their function in a safe manner within the temperature range from 65 8C to their specified minimum temperature and the pressure range intended for use. 4.2.2 Packing gland Valves can have an extended stem. The length of the extension shall be sufficient to maintain the stem packing at a temperature high enough to permit operation within the normal temperature range of the packing material. Valves without an extended stem shall have a stem packing capable of operating at the specified minimum temperature. The handle shall be designed to remain operable for the duration of the sample valve test in accordance with 5.2.3.2. Gland designs incorporating a gland nut with a male or female thread shall be designed in such a way that they will not unscrew unintentionally, for example when the valve is operated. 4.2.3 Operating positions As a minimum requirement, valves with extended stem shall be capable of operation with the valve stem at any position from the vertical to 258 above the horizontal. 4.2.4 Trapped liquid Cavities where liquid can be trapped and build up detrimental pressures due to evaporation of the liquid during warming-up of the valve are not permitted. NOTEFor ball and gate valves, this requirement can be met by the provision of a pressure-relief hole or passage or other means, e.g. pressure-relieving seats, to relieve pressure in the bonnet and body cavities to the upstream side of the valve. 4.2.5 Valve bonnet Valve bonnets may be brazed, welded, bolted, screwed or union type. Union type bonnets shall not be used on valves greater than DN 50. Union nuts shall be locked to the body. Screwed bonnets shall also be secured by a union nut or another device offering equivalent safety. 4.2.6 Securing of gland extension For bronze or copper alloy valves of PN 100 or greater, the gland extensions shall be mechanically secured in the bonnet prior to brazing for instance by screwing. 4.2.7 Seat Valves may have a metal/metal or metal/soft seat or insert. Soft seats shall be backed by a secondary metal seat. Soft seat materials shall be adequately supported to prevent cold flow of the seat material. 4.2.8 Blow-off safety of the stem The valve stem shall be secured so that it cannot be blown out of the body if the gland is removed while the valve is under pressure. 4.2.9 Torque The maximum torque, in newton metres, to operate the valves manually under service conditions, when applied at the rim of the handwheel or lever, shall not exceed 350 3 R, except for valve seating and unseating, when it shall not exceed 500 3 R. For a handwheel, R is the radius of the wheel in metres. For a lever, R is the length of the lever in metres, minus 0,05 m. The valve shall be robust enough to withstand 3 times the maximum torque as specified above without damage. Valves intended for actuator operation may have torque or linear force requirements deviating from the above. The sample valve tests shall then be pered using a suitable actuator to operate the valve. 4.2.10 Electric continuity and explosion protection All valves shall have a maximum electrical resistance of 10 V, in order to ensure electrical continuity to prevent build-up of static electricity. For flammable fluids, any equipment attached to or associated with a valve shall be suitable for the hazard zone. 5 Testing 5.1 Production tests The production test shall be pered in accordance with the requirements of applicable valve product standards. If these standards refer to ISO 5208, closure test leakage rate A is required. 5.2 Sample valve tests 5.2.1 Selection of sample valves One sample valve shall be tested. It shall be representative of the valves to be produced. If a range of valves of identical design but different sizes is to be tested, one sample of the smallest and one sample of the largest shall be tested. 5.2.2 Verification of the design A second sample valve shall be i