WELDED, PLASTIC FLANGE CONNECTION

摘要

The present invention is directed to a welded flange connection (50) and to methods and apparatus for producing the connection. A weld insert (20) is disposed between the flared ends (54, 58) of abutted plastic pipe (52) or plastic-lined pipe sections (56). The weld insert (20) includes an annular support disc (22) having a resistance heating element (30) disposed at least about the inner circumference (24) of the disc (22). When held tightly between the flared ends (54, 58) of abutted pipe sections power can be applied to the heating element (30) to produce sufficient heat to temporarily raise the temperature of the adjacent surfaces of the flared sections of pipe above their melting point. When the weld is cooled, a strong, fluid-tight, thermoplastic weld is formed. Further, by reapplying power to the insert, which remains embedded in the weld, the method of the present invention permits the weld to be easily disassembled for repairs to a pipe system.