| http://www.w3.org/ns/prov#value | - ove on its outer periphery and at least two annular grooves on its inner surface, said portion further including a plurality of annular sealing surfaces for establishing a metal-to-metal seal with said bonnet and stem, and b. flexible non-metallic sealing material within and filling said grooves, said sealing surfaces responding to said axial compressive force by establishing a metal-to-metal seal
|
