Applied norm 1、Design and manufacture:ASME/ANSI B16.34 API 600;GB/T12224;GB/T12228;GB/T12236 2、Face to face:ASME/ANSI B16.10;JB/T96-95 3、Dimension of flange:ASME/ANSI B16.5 JB/T82.1-82.2 4、Structural feature:B.C;springLifting,piston lifting and swing type 5、Sealing accessory material:according to "ordering guide" 6、Body material:A105;LF2;F5;F11;F22;F304;F316;F304L;F316L 7、Valve inspection and test according to API 598 or GB/T13927