【BS英國(guó)標(biāo)準(zhǔn)】BS EN 730-2-2002 Gas welding equipment — Safety devices — Part 2 Not incorporating a flame (flashback) arrestor.doc

-,-,-british standardbs en730-2:2002gas welding equipment safety devices part 2: not incorporating a flame(flashback) arrestorthe european standard en 730-2:2002 has the status of abritish standardics 25.160.30 copyright british standards institutionreproduced by ihs under license with bsi - uncontrolled copydocument provided by ihs licensee=bureau veritas/5959906001, 11/08/200405:32:45 mst questions or comments about this message: please call the documentpolicy group at 303-397-2295.bs en 730-2:2002national forewordthis british standard is the official english language version of en 730-2:2002. together with bs en 730-1:2002 it supersedes bs en 730:1995 which is withdrawn.the uk participation in its preparation was entrusted to technical committeewee/18, gas welding appliances, which has the responsibility to:aid enquirers to understand the text;present to the responsible international/european committee any enquiries on the interpretation, or proposals for change, and keep the uk interests informed;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-referencesthe british standards which implement international or european publications referred to in this document may be found in the bsi catalogue under the section entitled “international standards correspondence index”, or by using the “search” facility of the bsi electronic catalogue or of british standards online.this 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 does not of itself confer immunity from legal obligations.-,-,-this british standard, having been prepared under the direction of the engineering sector policy and strategy committee, was published under the authority of the standards policy and strategy committee on13 november 2002 bsi 13 november 2002isbn 0 580 40733 0summary of pagesthis document comprises a front cover, an inside front cover, the en title page,pages 2 to 14, an inside back cover and a back cover.the bsi copyright date displayed in this document indicates when the document was last issued.amd. no.datecommentsamendments issued since publication-,-,-european standard norme europenneeuropische normen 730-2october 2002ics 25.160.30english versiongas welding equipment - safety devices - part 2: not incorporating a flame (flashback) arrestormatriel de soudage aux gaz - dispositifs de scurit - partie 2: sans arrt de flammegasschweigerte - sicherheitseinrichtungen - teil 2: ohne integrierte flammensperrethis european standard was approved by cen on 8 august 2002.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 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 translation under the responsibility of a cen member into its own language and notified to the management centre 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, malta, netherlands, norway, portugal, spain, sweden, switzerland and united kingdom.european committee for standardization c o m i t eur o p en de nor m a l i s a ti on eur o p i s c h es kom i tee f r nor m ung management centre: rue de stassart, 36 b-1050 brussels 2002 cenall rights of exploitation in any form and by any means reserved worldwide for cen national members.ref. no. en 730-2:2002 een 730-2:2002 (e)contentspageforeword .31scope .42normative references .43terms and definitions.44design and materials .64.1connections .64.2materials.65requirements .75.1general .75.2gas tightness .75.3pressure resistance .75.4non-return valve .85.5pressure relief valves .85.6excess flow cut-off valves .85.7flashback resistance.86methods for type testing .86.1general .86.2accuracy of pressure and flow measurements .86.3test gases.86.4gas tightness test .96.5pressure resistance test .96.6non-return valve test .96.7pressure relief valves .96.8excess flow cut-off valve .96.9internal leakage test for cut-off valves .107manufacturers instructions.108marking .10annex a (informative) gas flow measurement .12a.1general .12a.2procedure .12annex b (informative) third party testing information.14b.1general .14b.2samples and documentation .142-,-,-en 730-2:2002 (e)forewordthis document en 730-2:2002 has been prepared by technical committee cen/tc 121 welding, the secretariat of which is held by ds.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 april 2003, and conflicting national standards shall be withdrawn at the latest by april 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 730-1 supersedes en 730:1995. annexes a and b are informative.-,-,-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, malta, netherlands, norway, portugal, spain, sweden, switzerland and the united kingdom.3copyright british standards institutionreproduced by ihs under license with bsi - uncontrolled copydocument provided by ihs licensee=bureau veritas/5959906001, 11/08/200405:32:45 mst questions or comments about this message: please call the documentpolicy group at 303-397-2295.en 730-2:2002 (e)1scopethis part of this european standard specifies the general requirements and tests for safety devices for fuel gases and oxygen or compressed air which do not incorporate a flame (flashback) arrestor used downstream of manifold, cylinder and (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 incorporate a flame arrestor which are covered by en 730-1.2normative referencesthis european standard incorporates by dated or undated reference, provisions from other publications. these normative references are cited at the 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 (including amendments).en 560, gas welding equipment hose connections for equipment for welding, cutting and allied processes.en 561, gas welding equipment quick-action coupling with shut-off valves for welding, cutting and allied processes.en 730-1:2002, gas welding equipment safety devices part 1: incorporating a flame (flashback) arrestor.en 29090, gas tightness of equipment for gas welding and allied processes (iso 9090:1989).en 29539, materials for equipment used in gas welding, cutting and allied processes (iso 9539:1988).en iso 2503, gas welding equipment pressure regulators for gas cylinders used in welding, cutting and allied processes up to 300 bar (iso 2503:1998).en iso 7291, gas welding equipment - pressure regulators for manifold systems used in welding, cutting and allied processes up to 300 bar (iso 7291:1999).iso 554, standard atmospheres for conditioning and/or testing specifications.3terms and definitionsfor the purposes of this european standard, the following terms and definitions apply.3.1excess flow cut-off valvedevice which stops the gas flow in the event of flow exceeding a predetermined valueexamplevalve is held open by a spring; it closes when the force caused by the dynamic pressure becomes greater than the force of the spring. a resetting device is necessary.4-,-,-copyright british standards institutionreproduced by ihs under license with bsi - uncontrolled copydocument provided by ihs licensee=bureau veritas/5959906001, 11/08/200405:32:45 mst questions or comments about this message: please call the documentpolicy group at 303-397-2295.en 730-2:2002 (e)key1normal direction of gas flowfigure 1 excess flow cut-off valve (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 functionsexamplenon-return valve and excess flow cut-off valve.3.4non-return valvedevice which prevents passage of gas in the direction opposite to flowexamplevalve is held open by energy in gas stream and closes when downstream pressure is approximately equal to or greater than that in normal direction of flow.5-,-,-en 730-2:2002 (e)key1normal direction of gas flowfigure 2 non-return valve (example)3.5pressure relief valvedevice which automatically vents gas when the pressure exceeds some predetermined value and seals again when the pressure returns to within specified limits of that valueexamplevalve is held closed by a spring; it opens when force caused by internal pressure rise exceeds the spring load.figure 3 pressure relief valve (example)3.6safety devicedevice for welding equipment which averts risk in case of misuse or malfunction of the down-stream gas welding equipment4design and materials4.1connectionsthreaded connections up to g1 shall be in accordance with en 560. quick release connections shall be in accordance with en 561.4.2materialsmaterials used for safety devices shall conform to the requirements laid down in en 29539.6-,-,-en 730-2:2002 (e)5requirements5.1generala summary of the requirements and test sequence for each device is given in table 1.table 1 summary of requirements and test sequence for safety devicessafety device function(s)require- ments (clause no)tests (in test order) (clause no)number of devices required for each testtotal number of devices requirednon-return valve. external gas tightness6.5 pressure resistance6.6 reverse flow6.9 internal leakage51 a556pressure relief valve5.56.4 external gas tightness6.5 pressureresistance6.7 relief pressure and flow51 a56excess flow cut-off valve. external gas tightness6.5 pressureresistance6.8 excessflowcut-off6.9 internal leakage51 a556ause a new device for this test. do not use for any other test.notein the following sub-clauses, the terms “upstream” and “downstream” refer to the normal direction of gas flow in the device.5.2gas tightness5.2.1external gas tightnessthe general requirements on external gas tightness and the test procedures shall be in accordance with en 290internal gas tightnesswhere internal gas tightness is required in this standard the leakage rate shall not exceed 50 cm3/h for devices with a connection internal bore (diameter) less than 11 mm or 0,41 d2 for larger diameters (for tests see 6.6 and/or6.9).notethe value 0,41 d2 is the flow in cm3/h where d is the internal bore (diameter) in mm of the largest connection of the device.5.3pressure resistancethe housings of the safety devices shall resist a pressure equal to ten times the maximum operating pressure, with the test pressure in all cases not less than 60 bar1).1)1 bar = 0,1 mpa = 105 pa1 pa = 1 n/m2all pressures are gauge pressure.7-,-,-,-,-en 730-2:2002 (e)when the device is tested in accordance with 6.5, no permanent deformation of the pressure retaining components shall occur after a test duration of at least 5 min.5.4non-return valvenon-return valve shall n