Oil well pipe joint - with metallic sealing contact by convex and conical sections both sides of taper thread

摘要

A threaded joint for oil well pipes has at the inner end of the female taper thread an unthreaded conical section and at the outer end a convex section. The former makes up a seal with a contacting convex section at the outer end of the male taper thread, and the latter forms a seal with an unthread conical section of the male taper thread. Semicircular grooves between thread and conical part assist the simultaneous engagement. This results in a reliable metal-to-metal seal at both thread ends in which the lateral seals are assisted simultaneously engaged face contacts.