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) According to customer's require