An improved seal between pipes

Abstract

The invention relates to a screwthreaded pipe joint comprising a pin(20) having at one end a male screw-threaded portion and a box(10) having at one end a female portion having a complementary screw-thread. The pin and box inter engage along the threaded portions with the male thread extending to a male stop shoulder adjacent a complementary stop shoulder on the olher portion. The complementary stop shoulder comprises a recess in the form of a cone receiver having a radial surface(23) adjacent a corresponding radial surface(15) on the complementary stop shoulder. A curved sealing surface(24) on the pin(20) sealingly engages a corresponding curved scaling surface(16) on the complementary stop shoulder of the box(10), each curved sealing surface(16,24) lying on the are of the circumference of a separate circle, and wherein the curvature of the box sealing surface(16) is greater than on the sealing surface(24) on the pin(20). surface(24) on the pin(20).