Flexible expansion pipe coupling

摘要

A coupling is made up of annular resilient packing members having on their peripheral surfaces, a sleeve having flanges secured to opposite ends of the sleeve, and annular projections formed on the inner surface of the sleeve. When the packing members are inserted between the sleeve and pipes to be connected together, the projections are received in the grooves. The opposing ends of the packing members are respectively provided with pairs of lips. Before insertion, each pair of lips are separated away by a distance between the sleeve and the pipe, so that when each packing member is inserted the distance between the lips is decreased so that lips firmly engage the sleeve and pipes thus forming a resilient seal. As a consequence the coupling is flexible and can move relative to the pipes.