??Application criterion 1??Design and manufacture??to ANSI B16.34;API602 2??Size of coupling end: (1).Size of socket joint hole:to ANSI B16.11,JIS B23.6 (2).Size of threaded end :to ANSI B1.20.1:BS21:JIS BO203:S107/1 3??Valve inspection and test??to API 598 4??Structure characteristics??B.B;OS&Y OR W.B;OS&Y 5??Material:to AIS/ASTM 6??Materiare fo main body?? A105??F5??F11??F22??304??304L??316??316L??LF2.etc