API Gate Valve Certification:API6A,ISO9001, Size: 1-13/16"~9" Pressure: 2000~20000psi Material: AA-HH API6A Gate Valve Certification:API6A,ISO9001,Size ... bonet2.metal-to-metal seat to body interface3.gate & seat design for slab gate 4.gate & seat design for expanding gate5.Bi- ... in designing and producing forged material, wellhead equipment( API 6A valves), API 6D pipe line valves, x-mas tree, BOP, ...