1、BRITISH STANDARD BS 341-1:1991 Incorporating Amendment No. 1 Transportable gas container valves Part 1: Specification for industrial valves for working pressures up to and including300barBS341-1:1991 This British Standard, having been prepared under the directionof the Pressure VesselStandards Polic
2、y Committee, was published underthe authority of the Standards Board and comes intoeffect on 30September1991 BSI 10-1999 First published March 1931 Second edition April 1945 Third edition October 1962 Fourth edition September 1991 The following BSI references relate to the work on this standard: Com
3、mittee reference PVE/3 Draft for comment88/77850 DC ISBN 0 580 19748 4 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Pressure Vessel Standards Policy Committee (PVE/-) to Technical Committee PVE/3, upon which the following bodies were
4、represented: Aluminium Extruders Association Aluminium Federation Associated Offices Technical Committee British Compressed Gases Association British Fire Consortium British Fire Protection Systems Association Ltd. British Railways Board British Soft Drinks Association Ltd. Chief and Assistant Chief
5、 Fire Officers Association Department of Trade and Industry Mechanical Engineering and Manufacturing Technology Division (Mmt) Department of Trade and Industry (National Engineering Laboratory) Department of Trade and Industry (National Physical Laboratory) Department of Transport (Marine Directorat
6、e) Engineering Equipment and Materials Users Association Fire Extinguishing Trades Association Health and Safety Executive Home Office Industrial Safety (Protective Equipment) Manufacturers Association Institute of Refrigeration Institute of Chemical Engineers Liquefied Petroleum Gas Industry Techni
7、cal Association (UK) Ministry of Defence Amendments issued since publication Amd. No. Date Comments 7641 May 1993 Indicated by a sideline in the marginBS341-1:1991 BSI 10-1999 i Contents Page Committees responsible Inside front cover Foreword iii Section 1. General 1.1 Scope 1 1.2 References 1 1.3 D
8、efinitions 1 1.4 Classification and types of valves 3 1.5 Classification of gases 3 1.6 Information and requirements to be agreed and to be documented 7 Section 2. Material requirements 2.1 General 10 2.2 Pressure containing components 10 2.3 Protective finishes 10 Section 3. Design 3.1 Design crite
9、ria 11 3.2 Dimensions 11 3.3 Valve stems 12 3.4 Valve outlets and connectors 12 3.5 Tolerances 12 Section 4. Pressure relief devices 4.1 Design of pressure relief devices 35 4.2 Relief pressures 35 4.3 Installation and application of pressure relief devices 36 Section 5. Manufacture and workmanship
10、5.1 Machining 37 5.2 Screw threads 37 5.3 Heat treatment of valve bodies 37 5.4 Protective finishes 37 5.5 Cleaning 37 5.6 Lubrication 37 5.7 Assembly and assembly torques 37 Section 6. Inspection and testing 6.1 Prototype and proving tests 38 6.2 Production sample testing 39 6.3 Production inspecti
11、on and testing 39 6.4 Gland leakage test 39 6.5 Valve seat leakage test 40 6.6 Bursting disc test 40 6.7 Final inspection 40 Section 7. Marking and packing 7.1 Marking 41 7.2 Packaging and protection 41 7.3 Certification 41 Section 8. Periodic inspection, testing and maintenance of valves 8.1 Genera
12、l 43 8.2 In service performance, inspection and test 43 8.3 Full inspection, test and maintenance 44BS341-1:1991 ii BSI 10-1999 Page 8.4 Marking and certification 45 8.5 Packaging and protection 45 Annex A (informative) Recommendations for plating of copper alloy valves 46 Annex B (informative) Valv
13、ing 47 Annex C (informative) American (CGA) valve outlet connections used in the UK 49 Annex D (informative) Gases conveyed in containers having outlet connections not covered in this standard 49 Annex E (informative) Conveyance test 50 Annex F (informative) Comparison between valve tapered inlet co
14、nnections in the current edition and the nominal sizes in BS341-1:1962 50 Annex G (informative) Recommended gauging for taper threads 51 Annex H (informative) Notes on the calculation of thread data given in Figure 6 a) to Figure 6 f) 60 Figure 1 Illustration of typical direct acting valves 4 Figure
15、 2 Illustration of a typical indirect acting valve 5 Figure 3 Illustration of a typical valve with diaphragm gland 5 Figure 4 Illustrations of typical key operated valves 6 Figure 5 Dimensions and tolerances of outlet connections 13 Figure 6 Dimensions and manufacturing tolerances of valve body tape
16、red stem/container neck threads 27 Figure 7 Dimensions and manufacturing tolerances of valve body parallel stem/container neck threads 33 Figure 8 Typical test rig for valve impact test 34 Figure 9 Typical example of marking layout for gas container valves 42 Figure G.1 Thread form for 16T plug and
17、ring gauges 52 Figure G.2 Thread form for18T,19T,25T and26T plug and ring gauges 53 Figure G.3 Thread form for32T plug and ring gauges 54 Figure G.4 Inspection plug gauges 55 Figure G.5 Inspection ring gauges 56 Figure G.6 Check gauges for inspection ring gauges 57 Figure G.7 Use of inspection plug
18、gauges 58 Figure G.8 Use of inspection ring gauges 59 Figure G.9 Use of check gauges 60 Table 1 Outlet connections and preferred materials for use with industrial gases 7 Table 2 Maximum diameter of valve stem gas passages 11 Table 3 Impact test values 38 Table B.1 Range of recommended valving torqu
19、es for 18T and25T tapered stem threads 48 Table B.2 Range of recommended valving torques for parallel stem threads 49 Table F.1 Comparison between valve tapered inlet connections in the current edition and the nominal sizes in BS341-1:1962 50 List of references 62BS341-1:1991 BSI 10-1999 iii Forewor
20、d This Part of BS341 has been prepared under the direction of the Pressure Vessel Standards Policy Committee at the request of the Health and Safety Executive and supersedes BS341-1:1962 and BS341-2:1963, which are withdrawn. It details the design, manufacture and testing of valves fitted to contain
21、ers used for the conveyance of permanent, liquefiable and dissolved gases, except those for liquefied petroleum gas (LPG) applications. It has been revised to include the recommendations contained in the Report of the Home Office Gas Cylinders and Container Committee 1 (published in1969). This Part
22、of BS341 is restricted to monobloc valve bodies and fittings. The opportunity has been taken to bring together into this Part of BS341 the current requirements for container valves previously given in BS341-1:1962 and BS341-2:1963, covering the following: 1) material requirements, design, manufactur
23、e, inspection and testing of new valves; 2) dimensioning of valve stems and outlet connections; 3) periodic inspection, testing and maintenance of valves in service. NOTEAdditional requirements may be necessary to cover the design, manufacture and construction of valves fitted to containers for mili
24、tary use. 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
25、comprises a front cover, an inside front cover, pagesi to iv, pages1to62, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.iv blankBS341-1:1991
26、BSI 10-1999 1 Section 1. General 1.1 Scope This Part of BS341 specifies requirements for the design, materials, manufacture and testing of new and refurbished valves together with the testing, periodic inspection and maintenance of valves in service, for use with refillable aluminium and steel conta
27、iners manufactured for the suitable conveyance and storage of permanent, liquefiable and dissolved gases for industrial applications, but excluding valves with outlets conforming to BS1319. This Part of BS341 applies to valves limited to a charging pressure (see1.3.19) of300 bar 1)(developed pressur
28、es for particular gases may exceed this pressure). This Part of BS341 also gives requirements for the design, manufacture, testing and installation of pressure relief devices, to protect containers up to130L capacity from excessive pressure, particularly when exposed to heat. WARNING. It is essentia
29、l that pressure relief devices should not be used with toxic gases. Recommendations for the plating of copper alloy valves are given in Annex A and recommendations for the valving of containers are given inAnnex B. Alist of the alternative outlets for the less commonly used gases imported into the U
30、nited Kingdom is given inAnnex C. This Part of BS341 does not include requirements for the selection of valve outlets and materials for gas mixtures, valves for medical applications complying with BS1319 and ultra-high-purity gases. This part of BS341 does not cover valves for liquefied petroleum ga
31、s (LPG). 1.2 References 1.2.1 Normative references This Part of BS341 incorporates, by reference, provisions from specific editions of other publications. These normative references are cited at the appropriate points in the text and the publications are listed on page 62. Subsequent amendments to,
32、or revisions of, any of these publications apply to this Part of BS341 only when incorporated in it by updating or revision. 1.2.2 Informative references This Part of BS341 refers to other publications that provide information or guidance. Editions of these publications current at the time of issue
33、of this standard are listed on page 62, but reference should be made to the latest editions. 1.3 Definitions For the purposes of this Part of BS341, the following definitions apply. 1.3.1 valve body the major valve component which includes an inlet and an outlet and, where applicable, a boss for a p
34、ressure relief device 1.3.2 spindle the element of the valve which, when operated, directly or indirectly actuates the sealing member (seal) to an open or closed position 1.3.3 seating face the fixed contact face in the valve body for completing the seal against gas flow 1.3.4 valve stem the inlet c
35、onnection fitted to the container 1.3.5 valve outlet the service connection 1.3.6 container neck the part of the container that has the threaded connection for the valve stem 1.3.7 dip (or syphon) tube a tube fitted to the valve to allow withdrawal of liquefied gas without inversion of the container
36、 1.3.8 goose neck eductor a tube fitted to the valve stem to allow withdrawal of vapour or liquefied gas when the container is correctly positioned on its side 1.3.9 oversized valve a valve having a larger than normal stem thread to suit an oversized container neck thread 1.3.10 vapour/liquid valve
37、a valve designed so that either vapour or liquid may be discharged without inverting the container NOTEThe valve may have separate vapour and liquid outlets or a common outlet. 1) bar = 10 5N/m 2=100kPa.BS341-1:1991 2 BSI 10-1999 1.3.11 thread sealant a material applied to a taper thread to effect a
38、 gas tight joint. It fills the cavity remaining in the helix of mating threads 1.3.12 pressure relief device a device designed to reduce the possibility of failure of a charged container from excessive pressure particularly when the container is exposed to heat 1.3.13 pressure relief valve a pressur
39、e relief device that is in direct contact with the gas, and is designed to open and close within predetermined pressure limits 1.3.14 bursting disc a pressure relief device consisting of a disc that is in direct contact with the gas and is designed to rupture between predetermined pressure limits 1.
40、3.15 fusible plug a device containing a material of low melting point which is in direct contact with the gas. It is intended to yield or melt within predetermined limits of temperature and permit the discharge of the contained gas 1.3.16 start-to-discharge pressure the pressure at which the leakage
41、 rate from a pressure relief device first exceeds10 3torrL/s 2) 1.3.17 flow rating pressure the pressure at the inlet of a pressure relief device which is used for establishing its rated flow capacity 1.3.18 rated flow capacity the capacity of a pressure relief device measured in cubic metres per mi
42、nute of free air at the designed flow rating pressure 1.3.19 charging pressure the settled pressure at a uniform temperature of15 C at full gas content 1.3.20 specified bursting pressure the nominal pressure at which a bursting disc is designed to rupture 1.3.21 maximum bursting pressure the specifi
43、ed bursting pressure plus the upper permitted design tolerance 1.3.22 leak an unintended flow of gas or liquid in excess of10 3torrL/s 1.3.23 ageing a change in a metal by which its structure recovers from an unstable condition produced by quenching or cold working 1.3.24 stress relieving a process
44、to reduce internal residual stresses in a metal by heating it to a suitable temperature for a stipulated period of time 1.3.25 normalizing a process in which a carbon or alloy steel is heated to a temperature above its upper transformation temperature (known as the solution temperature) and subseque
45、ntly cooled in still air 1.3.26 quenching a process in which a material is heated to a temperature above its upper transformation temperature (known as the solution temperature) and then quenched in a suitable medium 1.3.27 prototype test a test or series of tests directed towards approval of a desi
46、gn, conducted to determine whether an item is capable of meeting the requirements of the product specification 1.3.28 proving tests tests carried out on representative samples of the first production run of valves to determine the rated flow capacity and other operating characteristics 1.3.29 direct
47、 acting valve a valve in which the sealing member is downstream of the seating face and the gas pressure tends to open the valve 2) 10 3torrL/s 2= 5 mbarL/h. 133.3 10 6Nm/s. An approximate indication of this leakage rate would be the formation of four3.5mm diameter or ten2.5mm diameter bubbles per m
48、inute.BS341-1:1991 BSI 10-1999 3 1.3.30 indirect acting valve a valve in which the sealing member is upstream of the seating face and the gas pressure tends to close the valve 1.3.31 inspection gauge gauge used for the routine gauging of cylinder neck and valve stem thread. They are not for checking
49、 other gauges 1.3.32 check gauge a gauge for checking dimensional conformity of inspection gauges. They are not for gauging of cylinder neck and valve stem threads 1.3.33 single piece gauge an inspection gauge designed to contact the full length of taper thread. These gauges are plug or ring, smooth or threaded types 1.3.34 two piece gauges two inspection gauges to be used in combination, where one is designed to contact the large end of the taper cone and the other the small end. These sets of gauges are plug o
