1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA
2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any
3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ICS 25.160.30 ISBN 0-626-15225-9 SANS 50730-1:2004 Edition 1 EN 730-1:2002 Edition 2 SOUTH AFRICAN NATIONAL STANDARD Gas welding equipment Safety devices
4、 Part 1: Incorporating a flame (flashback) arrestor This national standard is the identical implementation of EN 730-1:2002 and is adopted with the permission of CEN, rue de Stassart 36, B-1050 Brussels. Published by Standards South Africa 1 dr lategan road groenkloof private bag x191 pretoria 0001
5、tel: 012 428 7911 fax: 012 344 1568 international code + 27 12 www.stansa.co.za Standards South Africa 2004 SANS 50730-1:2004 Edition 1 EN 730-1:2002 Edition 2 Table of changes Change No. Date Scope Abstract Specifies requirements for safety devices in gas welding equipment for fuel gases and oxygen
6、 or compressed air incorporating a flame (flashback) arrestor. Covers requirements for the design and material of safety devices. Provides test procedures for gas tightness and pressure resistance and methods of type testing. Keywords check valves, compressed air, definitions, fire cut off systems,
7、flame traps, flow measurement, flow rates, gas welding, gaseous fuels, line pressure, marking, oxygen, oxygen cutting, safety, safety devices, specification (approval), specifications, stopping, testing, welding equipment. National foreword This South African standard was approved by National Commit
8、tee StanSA SC 5120.19B, Gas supply, handling and control (fuel and industrial gases) Industrial gas, in accordance with procedures of Standards South Africa, in compliance with annex 3 of the WTO/TBT agreement. EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 730-1October 2002ICS 25.160.30English v
9、ersionGas welding equipment - Safety devices - Part 1: Incorporating aflame (flashback) arrestorMatriel de soudage aux gaz - Dispositifs de scurit -Partie 1: Avec arrt de flammeGasschweigerte - Sicherheitseinrichtungen - Teil 1: Mitintegrierter FlammensperreThis European Standard was approved by CEN
10、 on 8 August 2002.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-date lists and bibliographical references concerning such nationalstandards may
11、be obtained on application to the 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 responsibility of a CEN member into its own language and notified to the Managemen
12、t Centre has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.E
13、UROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2002 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 730-1:2002 EEN 730-1:2002 (E
14、)2ContentspageForeword31 Scope 42 Normative references 43 Terms and definitions44 Design and materials.74.1 Connection .74.2 Materials75 Requirements .75.1 General75.2 Gas tightness .95.3 Pressure resistance.95.4 Flame arrestor 95.5 Flame arrestor with non-return valve 95.6 Flame arrestor with tempe
15、rature sensitive cut-off valve.95.7 Flame arrestor with pressure-sensitive cut-off valve 95.8 Other multifunctional safety devices.106 Methods for type testing .106.1 General106.2 Accuracy of pressure and flow measurements106.3 Test gases.106.4 Gas tightness test106.5 Pressure resistance test .106.6
16、 Non-return valve test .116.7 Flame arrestor test.116.8 Temperature-sensitive cut-off valve test.136.9 Pressure-sensitive cut-off valve test .146.10 Internal leakage test for cut-off valves 147 Further tests .148 Manufacturers instructions149 Marking .15Annex A (informative) Gas flow measurement17A.
17、1 General17A.2 Procedure .17Annex B (informative) Third party testing information.19B.1 General19B.2 Samples and documentation19Annex C (informative) Production tests.20C.1 General20C.2 Production flashback test.20EN 730-1:2002 (E)3ForewordThis document EN 730-1:2002 has been prepared by Technical C
18、ommittee CEN/TC 121 “Welding“, the secretariatof which is held by DS.This European Standard shall be given the status of a national standard, either by publication of an identical text orby endorsement, at the latest by April 2003, and conflicting national standards shall be withdrawn at the latest
19、byApril 2003.This European Standard “Gas welding equipment Safety devices” consists of the following Parts:Part 1: Incorporating a flame (flashback) arrestor.Part 2: Not incorporating a flame (flashback) arrestor.This Part and EN 730-2 supersedes EN 730:1995.Annexes A, B and C are informative.Accord
20、ing to the CEN/CENELEC Internal Regulations, the national standards organizations of the followingcountries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland,France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Port
21、ugal, Spain,Sweden, Switzerland and the United Kingdom.EN 730-1:2002 (E)41 ScopeThis Part of this European Standard specifies the general requirements and tests for safety devices for fuel gasesand oxygen or compressed air incorporating a flame (flashback) arrestor used downstream of manifold, cylin
22、derand (or) pipeline outlet regulators, and upstream of blowpipes for welding, cutting and allied processes.This standard does not specify the location of these devices in the gas system.This standard does not include requirements for safety devices which do not incorporate a flame arrestor which ar
23、ecovered by EN 730-2.This standard does not cover the use of safety devices incorporating flame arrestors for applications with premixedoxy/fuel or air/fuel gas supply systems, for example downstream of gas mixers or a generator to producehydrogen/oxygen mixture by electrolytic decomposition of wate
24、r.2 Normative referencesThis European Standard incorporates by dated or undated reference, provisions from other publications. Thesenormative references are cited at the appropriate places in the text, and the publications are listed hereafter. Fordated references, subsequent amendments to or revisi
25、ons of any of these publications apply to this EuropeanStandard only when incorporated in it by amendment or revision. For undated references the latest edition of thepublication referred to applies (including amendments).EN 560, Gas welding equipment Hose connections for equipment for welding, cutt
26、ing and allied processes.EN 561, Gas welding equipment Quick-action coupling with shut-off valves for welding, cutting and alliedprocesses.EN 730-2, Gas welding equipment Safety devices Part 2: Not incorporating a flame (flashback) arrester.EN 29090, Gas tightness of equipment for gas welding and al
27、lied processes (ISO 9090:1989).EN 29539, Materials for equipment used in gas welding, cutting and allied processes (ISO 9539:1988).ISO 554, Standard atmospheres for conditioning and/or testing Specifications.3 Terms and definitionsFor the purposes of this European Standard, the following terms and d
28、efinitions apply.3.1flame arrestordevice which quenches a flame frontEXAMPLE The good thermal conductivity, high porosity and small pore size (larger surface) of sintered metal elementslead to flame quenching.EN 730-1:2002 (E)5Key1 Normal direction of gas flow2 E.g. sintered metal element3FlameFigur
29、e 1 Flame arrestor (example)3.2maximum operating pressuremaximum pressure to which the equipment may be subjected in service3.3multifunctional safety devicedevice which incorporates two or more of the safety functionsEXAMPLE Flame arrestor with non-return valve and cut-off valve.NOTE The temperature
30、 sensitive cut-off valve is normally used in combination with a flame arrestor as its purpose is to cut-off the gas flow before the temperature at the flame arrestor reaches a point where flame transmission across the flame arrestortakes place. It is normal for pressure and or temperature cut-off va
31、lves only to be used in combination with flame arrestors. Dueto the burning characteristics of hydrogen it is recommended all flame arrestors for hydrogen incorporate a temperaturesensitive cut-off valve.3.4non-return valvedevice which prevents passage of gas in the direction opposite to flowEXAMPLE
32、 Valve is held open by energy in gas stream and closes when downstream pressure is approximately equal toor greater than that in normal direction of flow.EN 730-1:2002 (E)6Key1 Normal direction of gas flowFigure 2 Non-return valve (example)3.5pressure-sensitive cut-off valvedevice which stops the ga
33、s flow in the event of a back-pressure wave from the downstream sideEXAMPLE Valve is held open, e.g. by a spring; it is actuated by a pressure wave from down-stream and is thenautomatically held closed by a special device.Key1 Normal direction of gas flow2 Back-pressure waveFigure 3 Pressure-sensiti
34、ve cut-off valve (example)3.6temperature-sensitive cut-off valvedevice which stops the gas flow when a predetermined temperature is exceededEXAMPLE Valve is held open, e.g. by a fusible metal, and actuated by sustained temperature rise.EN 730-1:2002 (E)7Key1 Normal direction of gas flow2 E.g. fusibl
35、e metalFigure 4 Temperature-sensitive cut-off valve (example)3.7safety devicedevice for welding equipment which averts risk in case of misuse or malfunction of the down-stream gas weldingequipment4 Design and materials4.1 ConnectionThreaded connections up to G1 shall be in accordance with EN 560. Qu
36、ick release connections shall be inaccordance with EN 561.4.2 MaterialsMaterials used for safety devices shall conform to the requirements laid down in EN 29539.5 Requirements5.1 GeneralRequirements for each safety device vary depending upon the device and combination of functions in the device. Asu
37、mmary of the requirements and test sequence is given in Table 1.EN 730-1:2002 (E)8Table 1 Summary of requirements and test sequence for the most commonly available safety devicesSafety devicefunction(s)Require-ments(ClauseNo)Tests (in test order)(Clause No)Number ofdevices requiredfor each testTotal
38、 number ofdevices requiredFlame arrestor 5.2.15.35.46.4 External gas tightness6.5 Pressure resistance6.7 Flashback resistance51 a56Flame arrestor + non-return valve5.2.15.2.25.35.56.4 External gas tightness6.5 Pressure resistance6.6 Reverse flow6.7 Flashback resistance6.6 Reverse flow51 a5556Flame a
39、rrestor +temperature sensitivecut-off valve5.2.15.2.25.35.66.4 External gas tightness6.5 Pressure resistance6.7 Flashback resistance6.8 Temperature cut-off6.10 Internal leakage51a51a57Flame arrestor + non-return valve +temperature-sensitivecut-off valve5.2.15.2.25.35.55.66.4 External gas tightness6.
40、5 Pressure resistance6.6 Reverse flow6.7 Flashback resistance6.6 Reverse flow6.8 Temperature cut-off6.10 Internal leakage51 a5551 a57Flame arrestor + non-return valve +pressure-sensitivecut-off valve5.2.15.2.25.35.55.76.4 External gas tightness6.5 Pressure resistance6.6 Reverse flow6.9 Pressure cut-
41、off6.10 Internal leakage6.7 Flashback resistance6.6 Reverse flow6.9 Pressure cut-off6.10 Internal leakage51a55555556Flame arrestor + non-return valve +temperature-sensitivecut-off valve +pressure-sensitivecut-off valve5.2.15.2.25.35.55.65.76.4 External gas tightness6.5 Pressure resistance6.6 Reverse
42、 flow6.9 Pressure cut-off6.10 Internal leakage6.7 Flashback resistance6.6 Reverse flow6.9 Pressure cut-off6.10 Internal leakage6.8 Temperature cut-off6.10 Internal leakage51 a55555551 a57aUse a new device for this test. Do not use for any other test.NOTE In the following sub-clauses, the terms “upst
43、ream” and “downstream” refer to the normal direction of gas flow in thedevice.EN 730-1:2002 (E)95.2 Gas tightness5.2.1 External gas tightnessThe general requirements on external gas tightness and the test procedures shall be in accordance with EN 29090.5.2.2 Internal gas tightnessWhere internal gas
44、tightness is required in this standard the leakage rate shall not exceed 50 cm3/h for deviceswith a connection internal bore (diameter) less than 11 mm or 0,41 d2for larger diameters (see 6.6 and/or 6.10 fortests).NOTE The value 0,41 d2is the flow in cm3/h where d is the internal bore (diameter) in
45、mm of the largest connection of thedevice.5.3 Pressure resistanceThe housings of the safety devices shall resist a pressure equal to ten times the maximum operating pressure, withthe test pressure in all cases not less than 60 bar1).When the device is tested in accordance with 6.5, no permanent defo
46、rmation of the pressure retaining componentsshall occur after a test duration of at least 5 min.5.4 Flame arrestorFlame arrestors shall quench flashbacks when tested in accordance with 6.7.5.5 Flame arrestor with non-return valveFlame arrestor with non-return valve shall quench flashbacks when teste
47、d in accordance with 6.7 and shall notallow the reverse flow of gases when tested in accordance with 6.6 both before and after the flashback test 6.7.5.6 Flame arrestor with temperature sensitive cut-off valveFlame arrestor with temperature-sensitive cut-off valve shall quench flashbacks when tested
48、 in accordance with 6.7and shall stop the gas flow before the upstream gas is ignited when tested in accordance with 6.8.It shall not be possible to reset the temperature sensitive cut off valve.If the temperature-sensitive cut-off valve operates before the fifth flashback in test 6.7 and the flame
49、is nottransmitted upstream the unit shall be considered to meet the flashback test requirement, but test 6.8 shall still becarried out on a new unit.5.7 Flame arrestor with pressure-sensitive cut-off valveFlame arrestor with pressure-sensitive cut-off valve shall quench flashbacks when tested in accordance with 6.7and the pressure-sensitive cut-off function shall activate at each flashback. The pressure-sensitive cut-off valveshall remain closed until it is manually reset.The pressure-sensitive cut-off valve shall
