ELECTROFUSION JOINT AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide an electrofusion joint equipped with a hollow pipe main body formed of a crosslinkable thermoplastic resin, and a pair of coils comprising one continuous electrically heated wire arranged at two positions separated from each other on the inner peripheral side of the hollow pipe main body and covered by a non-crosslinkable thermoplastic resin layer, capable of preventing leakage via an electrically heated wire part.

SOLUTION: The electrofusion joint is equipped with the hollow pipe main body and a heating element comprising one continuous electrically heated wire covered by a non-crosslinkable thermoplastic resin. The heating element is equipped with a first spiral part, a second spiral part and a connecting part for connecting the two spiral parts. The connecting part or at least one part of the inner peripheral side of the hollow main pipe main body adjacent to the connecting part has a position determining means for stopping the heating element inside a wall thickness part of the hollow pipe main body in cooperation with a core upon molding the hollow pipe main body by a resin.

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