Thin-walled connecting pipe for pipeline and coupling structure for same

Abstract From the Canadian patent

A thin-walled connecting pipe for a pipeline having an annular protuberance formed at a predetermined distance from a pipe end, the annular protuberance having an outer side face serving as a disengagement preventing face approximately perpendicular to the pipe axis, and the outer peripheral surface of a straight pipe portion on a front end side with respect to the annular protuberance serving as a seal ring abutting surface. Also disclosed is a coupling structure for such thin walled connecting pipe, the coupling structure comprising a socket and an annular nut the socket, having a seal ring for abutment with the seal ring abutting surface of the pipe and a recess for receiving the annular …