Abstract: Joint for pipes of the type in which an end of a male member (1) provided with a thread is screwed into a female member (2) having a corresponding thread.On its outer surface, the male member has a circumferential groove (9) and on the inner surface the female member has a circumferential groove (10) which, in the screwed position, faces the groove of the male member. A spring ring (12) is provided to simultaneously engage in the said grooves. At least one of the grooves has an adequate radial depth to permit the retraction of the spring ring when the male member is engaged in the female member.

Abstract: A joint for pipes in which externally threaded male members are screwed into an internally threaded sleeve. The ends of the male members have sealing surfaces thereon and are substantially cylindrical and thread-free. The ends are so formed that upon abutment they will be urged radially outwardly. The threaded sleeve has a substantially thread-free cylindrical sealing surface intermediate its ends. When the male members are screwed into the sleeve the ends abut causing the sealing surfaces of the male members to be forced radially outwardly into tighter sealing engagement with the sealing surface of the sleeve.