定价： 3959元 / 折扣价： 3366 元

Scope Details test and examination criteria for manually operated gas valves which are substantially of the plug and body, or rotating disc type, and to valves of other types which will provide equivalent performance. The standard presents minimum lev

定价： 774元 / 折扣价： 658 元

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1.1 Scope 1.1.1 This standard applies to the following types of relief valves constructed entirely of new, unused parts and materials: (a) Temperature relief valves and combination temperature and pressure relief valves for use on storage tanks of

定价： 3731元 / 折扣价： 3172 元

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1.1 Scope 1.1.1 These requirements apply to manually operated valves for high pressure natural gas. 1.1.2 These requirements do not apply to cylinder shut-off valves. 1.1.3 A valve that complies with the requirements for a Class A valve may b

定价： 637元 / 折扣价： 542 元

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