Pipe having coupling means

Claim 1

A length of pipe adapted to be joined end-to-end to a similar pipe without additional components to form a liquid-tight line, which pipe comprises a generally uniform tubular member, the outside surface adjacent the one end of said tubular member which serves as the spigot end of said pipe having a circumferential sealing band sealingly attached thereto, the radially outermost surface of said band being disposed a predetermined radial distance from the outside surface of said member, the other end of said tubular member having a sleeve of elastomeric thermoplastic material affixed to the outside circumferential surface of said member in liquid-tight relationship thereto as a result of having been heated and then forcibly expanded while hot during mounting upon said member, and a polymeric resin material coating the outer surface of said tubular member in the region of said sleeve, said sleeve having a portion extending a predetermined axial distance beyond the other end of said member which is larger in diameter over its entire length than the remainder of said sleeve, said extension portion having an inner diameter which is slightly smaller than the diameter of said sealing band, and said elastomeric extension portion being resiliently deformed radially outwardly when the band-carrying spigot end of another pipe length is pushed thereinto so that a narrow liquid-tight seal is formed between said band outermost surface and the inner surface of said sleeve extension portion.