Abstract: Elastomeric pipe separators (14) are interlocked with an internal stop collar (10a) of a pipe coupling (10) to enable pipes (16 and 18) to be inserted as far as they will readily go into the pipe coupling (10) and yet allow for thermal expansion of the pipes (16 and 18) without damage to the pipes (16 and 18) or coupling (10).

Abstract: The pipe coupling includes a hollow cylindrical body and pipe registering means projecting radially inward therefrom centrally thereof. The body has a pair of inner annular grooves respectively adjacent opposite ends for the reception of sealing rings. Both the body and the pipe registering means are formed of glass fiber reinforced thermosetting resin and each contains glass filament windings. A plastic film strip between the body and the pipe registering means maintains them separate as the resin of both is cured. Thereafter, any cracking of the pipe registering means will leave the body intact and a good pipe joint will be maintained.