1.Comply with the requirement of API SPEC 6A. 2.Driving mode:manual,gear drive,hydraulic 3. ... Feature in design :Comply with the requirement of API SPEC 6A,Valve structure includes both of styles,rising stem and non-rising stem ... drive and hydraulic,Gate structure:Integral,expanded,The sealing face of gate and seat is overlaying –welded with hard alloy with ...