1、BSISO25760:2009ICS23.020.30NOCOPYINGWITHOUTBSIPERMISSIONEXCEPTASPERMITTEDBYCOPYRIGHTLAWBRITISHSTANDARDGascylindersO perationalproceduresforthesaferemovalofvalvesfromgascylindersBS EN ISO 25760:2015BS EN ISO 25760:2015ISBN 978 0 580 88063 6Amendments/corrigenda issued since publicationDate Comments30
2、 April 2015 The corrigendum renumbers BS ISO 25760:2009 as BS EN ISO 25760:2015This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 July 2009 The British Standards Institution 2015. Published by BSI Standards Limited 2015National forewordThis B
3、ritish Standard is the UK implementation of EN ISO 25760:2015. It is identical to ISO 25760:2009. It supersedes BS ISO 25760:2009, which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee PVE/3, Gas containers.A list of organizations represented on this committ
4、ee can be obtained on request to its secretary.The publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.EUROPEAN STANDARD NORME EUROPENNE
5、EUROPISCHE NORM EN ISO 25760 February 2015 ICS 23.020.30 English Version Gas cylinders - Operational procedures for the safe removal of valves from gas cylinders (ISO 25760:2009) Bouteilles gaz - Modes opratoires de dpose en toute scurit des robinets de bouteilles gaz (ISO 25760:2009)Gasflaschen - V
6、erfahren fr das sichere Entfernen von Ventilen aus Gasflaschen (ISO 25760:2009) This European Standard was approved by CEN on 19 January 2015. 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 na
7、tional standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A v
8、ersion in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus
9、, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingd
10、om. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2015 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 2576
11、0:2015 EEN ISO 25760:2015 (E) 3 Foreword The text of ISO 25760:2009 has been prepared by Technical Committee ISO/TC 58 “Gas cylinders” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 25760:2015 by Technical Committee CEN/TC 23 “Transportable gas cylinder
12、s” the secretariat of which is held by BSI. 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 August 2015, and conflicting national standards shall be withdrawn at the latest by August 2015. Attenti
13、on is drawn to the possibility 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. According to the CEN-CENELEC Internal Regulations, the national standards organizations of th
14、e following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherl
15、ands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 25760:2009 has been approved by CEN as EN ISO 25760:2015 without any modification. BS EN ISO 25760:2015EN ISO 25760:2015 (E)BS ISO 25760:2009ISO
16、25760:2009(E) ISO 2009 All rights reserved iiiContents PageForeword ivIntroduction v1Scope . 12Normative references. 13Terms and definitions. 14General requirements. 34.1 Application 34.2 Hazards 34.3 Operator safetyand protection. 34.4 Operator qualifications.34.5 Operator errors .44.6 Special valv
17、e designs. 55Methods for inoperable valves 55.1 Summary of methods. 55.2 Choice of method 66Procedures 66.1 Procedures to identify and segregate cylinders with inoperable valves 66.2 Standard devalving procedure for treating cylinders with operable valves. 76.3 Procedures for treating cylinders with
18、 inoperable valves 87Damaged valves and cylinders . 8Annex A (informative) Reasons cylinder valves become inoperable. 9Annex B (informative) Examples of methods for depressurization of gas cylinders with inoperablevalves. 11Bibliography. 18BS EN ISO 25760:2015ISO 25760:2009(E)BS ISO 25760:2009ISO 25
19、760:2009(E)iv ISO 2009 All rights reservedForeword 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
20、body interested in a subject for which a technical committee has beenestablished 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 closelywith the International Electrot
21、echnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordancewith the rules given in the ISO/IEC Directives, Part 2.The main task of technical committees is to prepare International Standards. Draft International Standardsadopted by t
22、he technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval byat 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
23、. ISO shall not be held responsible for identifying any or all such patent rights. ISO25760 wasprepared by Technical Committee ISO/TC58, Gas cylinders, Subcommittee SC 4, Operational requirements for gas cylinders and is based on EIGADocument 129/05 Pressure receptacles withblocked or inoperable val
24、ves. EIGAhas granted permission to reproduce excerpts from their document. BS EN ISO 25760:2015ISO 25760:2009(E)BS ISO 25760:2009ISO 25760:2009(E) ISO 2009 All rights reserved vIntroduction Cylinders are devalved for many purposes, such as periodic inspection and testing, cylinder cleaning, change o
25、f service, replacement of a damaged valve, installation of a newvalve, preparation for filling or scrapping. Occasionally, gas cylinder valves can become blocked by corrosion or foreign material or become inoperabledue to external or internal damage. It is an essential safety requirement that such v
26、alved cylinders beidentified and treated with special care as soon as practicable. The operation of removing a valve should onlybe carried out if the cylinder is made safe with respect to residual gas and pressure. It is recommended that gas suppliers be prepared with both the proper equipment and t
27、rained operators for dealing with such valvedcylinders. Practical techniques that have been tried and tested over many years within the gas industry are described. Valve removal activities can pose hazards to the life and physical safety of the operator, especially if thecylinder is under pressure.
28、Valves should only be removed after ensuring there is no residual pressure in the cylinder. BS EN ISO 25760:2015ISO 25760:2009(E)BS ISO 25760:2009BS EN ISO 25760:2015BS ISO 25760:2009INTERNATIONAL STANDARD ISO 25760:2009(E) ISO 2009 All rights reserved 1Gas cylinders Operational procedures for the s
29、afe removal of valves fromgas cylinders1 Scope This International Standard is intended for suppliers, operators in testing facilities, operators performing cylinder maintenance and anyperson authorized to remove valves from gas cylinders. It details proceduresfor the safe removal of valves from cyli
30、nders and includes techniques for the identificationof inoperable valves. Only the risks due to gas and gas mixtures under pressure are addressed; other technical issues relating tothe removal of a valve from a cylinder are not covered.Some specialized equipment and procedures are in use in parts of
31、 the gas industryto safely remove cylindervalves from lowpressure gas cylinderswhile under pressure, e.g. liquefied petroleum gas (LPG); these techniques are not included in this International Standard. 2 NormativereferencesThe following referenced documents are indispensable for the application of
32、this document. For datedreferences, only the edition cited applies. For undated references, the latest edition of the referenceddocument (including anyamendments) applies.ISO 11114-1, Transportable gas cylinders Compatibility of cylinder and valve materials with gascontents Part1: Metallic materials
33、ISO 11114-2, Transportable gas cylinders Compatibility of cylinder and valve materials with gascontents Part 2: Non-metallic materials3 Terms and definitions For the purposes of this document, the following terms and definitions apply:3.1 gas cylinderpressure receptacle including individual cylinder
34、, tube, pressure drum ormanifold combination of these 3.2 valvedevice that allows gas to enter or exit a gas cylinder and retains the pressure in the cylinder when in the closed position NOTE This also includes the fittings of cylinders in bundles and battery vehicles. 3.3 inoperable valvevalve that
35、 is blocked, broken or malfunctioning or that in anywayprevents gas from entering or exiting the gascylinderNOTESee Annex A. BS EN ISO 25760:2015ISO 25760:2009(E)BS ISO 25760:2009ISO 25760:2009(E)2 ISO 2009 All rights reserved3.4 operable valvedevice that allows gas to enter or exit a gas cylinder3.
36、5 residual pressure valve RPVtype of valve that prevents the gas cylinder from being totally depressurized byholding back a specific amount of residual pressureNOTE 1 Requirements for this type of valve are specified in ISO15996. NOTE 2 This valve type is very often associated with a non-return func
37、tion. 3.6 valve with integrated pressure regulatorVIPRdevice intended to be permanently fitted to a gas cylinder connection and comprising a shut-off valve systemand pressure reduction systemNOTE 1 Adapted from ISO 22435:2007, definition 3.3. NOTE 2 Requirements for this type of valve are specified
38、in ISO15996. 3.7 pressure relief device PRD device that is fitted to the cylinder or cylinder valve and designed to relieve gas pressure in the event of abnormal conditions resulting in the development of excessive pressure inside the cylinder orwhen thecylinder is subjected to high temperaturesNOTE
39、1This might be a pressure relief valve, a non-reclosing PRD or a non-reclosing PRD in combination with apressure relief valve. NOTE2The expression “pressure relief” is synonymous with “safety relief”, as used in various applicable regulations,codes, standardsor specifications. 3.8 quick connect valv
40、eclip-on valve valve that does not contain an operating device, such as a handwheel 3.9 low pressure gas cylinder gas cylinder with test pressures no higher than 60 bar1)3.10 compressed gas gas which, when packaged under pressure for transport, is entirelygaseous at all temperatures above 50 CNOTE T
41、his category includes all gases with a critical temperature less than or equal to 50 C. 1) 1 bar = 100 kPa (exactly) BS EN ISO 25760:2015ISO 25760:2009(E)BS ISO 25760:2009ISO 25760:2009(E) ISO 2009 All rights reserved 34 General requirements 4.1 Application This clause gives general information to b
42、e considered. Clause 5 gives a choice of methods for inoperablevalves. Procedures to be followed are given in Clause6. 4.2 Hazards Especiallyif the cylinder is under pressure, valve removal methods pose certain hazards to the operator, suchas: stored energy from residual pressure (particularlyimport
43、ant if the cylinder is not in a vertical position); residual gas hazards,including fire resulting fromflammable gas ignitionsNOTE Oxidizing gases inthe presenceof contamination canalso cause severe ignition. asphyxiation, oxidation, toxicity/corrosivity, projection of pieces under pressure, cold bur
44、ns due to vaporization of liquefied gases; and operating devalving machinery and equipment, such as pinch points, rotation and powered machines. 4.3Operator safety and protection When an operator is removing a blocked or inoperable valve, other individuals should be on site and able torespond in cas
45、eof an emergency.A risk assessment shall be performed in order to avoid the exposure of the operator and other persons who could be affected by hazards.The minimum hazards to take into account for this risk analysis arelisted in 4.2. After the risk assessment is completed, risksshall be eliminated o
46、r minimized as far as reasonably practicable by engineering or process changes, such as shieldsorbunkers. The required or appropriatepersonnel protective equipment shall be chosen. 4.4 Operator qualifications4.4.1 General All operators shall have appropriatetraining, understanding of the cylinder co
47、ntent, when known, and the precautions which might be necessary to prevent the release or exposure to the gas (see 4.2, 4.3 and 5.2), and good practical understanding of the cylinder valve and the method of fitment to the cylinder. BS EN ISO 25760:2015ISO 25760:2009(E)BS ISO 25760:2009ISO 25760:2009
48、(E)4 ISO 2009 All rights reserved4.4.2 Specific process qualificationsDue to additional hazards that are present, operatorsshall receive specific training for the processesoutlinedin this International Standard. Such processes can include the pressure check, the devalving process, the inoperable val
49、ve process.Proper precautions shall be taken in the work area to protect operators from gas and particle discharges. Appropriate personal protection equipment shall be worn, and emergency equipment shall be readily available.Personal protection during devalving shall be adopted according to the hazards that may be present, such asthose indicated in 4.2. 4.5 Operator errorsAs a minimum, the following possibilities shall be considered in the context of operator errors. Incorrectly assuming that a cylinder has no
