OS&Y, Rising stem, Flexible Wedge Bolted bonnet, threaded or welded seat ring ASTM A216 WCB, A217 WC6, A351 CF8, A351 CF8M, A351 CF3, A351 CF3M, A351 CN7M Standards compliance Design and Manufacture: ANSI B16.34, API 600, API 6D, API 603, BS1414 Face to face (end to end): ANSI B16.10, API 6D Flanged connection: 2"~24" to ANSI B16.5, 22", 26"~36" to MSS-SP-44 to API605 on Request Test and inspection: API 598, API 6D Butt welded end: ANSI B16.5 A. Anti-friction ball thrust bearing: Reduces friction between mating parts to ensure smooth operation B. Grub screw: Secures yoke nut in the bonnet C. Grease nipple: Supplies lubricant to the mating parts