Features
1.Tow or Three pieces body
2.Fire-safe, antistatic and blow-out proof stem functions
3.Up stream sealing,down stream sealing,double sealing
4.Self relieving seat
5.Double block and bleed(DBB)function
6.Emergency sealant injection system
7.Stem/bonnet extension for cryogenic service 
Operation type
Handwheel,Gear, Electric actuator,Pneumatic actuator,Bare stem
Standard
Design and Manufacture:API 6D,API608,BS5351 or ASME B16.34
Inspection and Test:API 598/API 6D
End flange dimension:ASME B16.5,ASME B16.47(API 605 ,MSS SP44)
Butt weld end dimension:ASME B16.25(BW)
Face to face,end to end:ASME B16.10/API 6D
Pressure-temperature ratings:ASME B16.34
NACE: NACE 0175
Material

  ASTM A216 WCB WCC;ASTM A217 WC1 WC6 WC9;ASTM A351 CF8,A351 CF8M,
  A351 CF3,A351 CF3M,A351 CN7M;.ASTM A352 LC1 LCB LCC LC3(Cast Steel,

  Alloy Steel, Stainless Steel, Special Steel)