Patent ID: 6550822
Filing Date: 2003-04-22
Classification: E21B,F16L

Abstract:
A coupling for joining together two tubular sections, each tubular section having an end and an outer diameter with an unthreaded area and a threaded area between the unthreaded area and the end, the coupling having an inner diameter with an unthreaded central section having first and second opposing shoulders, and first and second end sections joined to the unthreaded central section, the first and second end sections having first and second ends respectively, comprising:(a) each of the first and second end sections of the coupling having an internally threaded area adjacent the central section and an unthreaded area between each internally threaded area and each end of the coupling; a thread compound relief groove in each unthreaded area between each internally threaded area and each end of the coupling, and a seal groove in each unthreaded area between each thread compound relief groove and each end of the coupling; and (b) a pressure energized resilient seal positioned in each of the seal grooves, each seal forming a seal between the unthreaded area of each tubular section and the unthreaded area of each end section, each seal being compressed radially between the unthreaded area of the tubular section and the unthreaded area of the end section.