China BB Cast Steel Globe Valve: Bolted Bonnet Cast Steel Globe Valves, 600LB, 12 Inch, WCB, WCC, LCB, Butt Welded, Plug Disc, ASME B16.34, BS 1873. Features: OS&Y, Rising Stem. Bolted Bonnet/Pressure Seal Bonnet. Plug Disc. Extended Bonnet for Cryogenic Services. Operation: Handwheel, Bevel Gear and Electric Operation.