A joint for joining the ends of two pipes (12, 14) has a socket (or box)
on the end of one pipe (14) into which the end (30) of the other pipe is
inserted. The part (36) of the socket which surrounds the inserted pipe
has an external tapered surface (38). A correspondingly tapered sleeve
(42) surrounds the socket and can be moved axially to apply a compressive
force to the taper on the socket which is thus compressed inward against
the inserted pipe end to frictionally grip the inserted pipe end.