Coupling adapter for plastic pipe

摘要

A means for adapting the end of a plastic pipe for coupling is provided in which the pipe is recessed circumferentially and the recessed area is further indented with three circumferential grooves. A first metal sleeve is shrink-fitted into the recessed area adjacent to the first groove furthest removed from the end of the pipe and further removed from the end of the pipe than this groove. A gasket ring of resilient material is inserted into a second groove which is between the first groove and the end of the pipe. A second metal sleeve having the same outside circumference as the third metal sleeve is shrink-fitted into the recessed area adjacent the first groove, encasing the gasket ring in the second groove, and indented into a first groove near the end of the pipe leaving a circumferential indentation spaced from the end of the pipe to receive one portion of a coupling device. A split locking ring having the same outside circumference as the first metal sleeve is inserted in the first groove and a third metal sleeve having an inner circumference sufficient slidably to engage the outer circumference of the first metal sleeve is slipped into position encasing the lock ring in the groove and overlapping the other two sleeves. Upon fixably attaching the third sleeve into position the plastic pipe is effectively covered with a metal adapter so that upon juxtaposition of two such adapted pipes a gasketed, split-ring coupling can be positioned into the grooves in the metal sleeves of the abutted pipe to lock the pipe in pressure-tight union.