Manufacturing method null of the electro- fusion coupling which uses the winding belt core and the said

摘要

PURPOSE: To eliminate or lower the a stopper for wire flow prevention by roughening a surface on which a heating wire of a core is wound, in an electro- fusion joint formed by an injection molding after a metal core on which the heating wire is wound is set in a metal mold. ;CONSTITUTION: Various types of electro-fusion joints such as socket joint, cheese joint, cap joint, etc., used in piping work for city water, sewerage, and city gas are formed by the injection mold after a metal coil core on which heating wire 1 is wound is set in a metal mold. It is fused for connection to a plastic tube by the heat with electricity through the heating wire 1. In this type of joint, a surface on which the heating wire 1 of the coil core is wound is treated to have rough surface. Thus the height of a stopper 2 formed at the end of the core can be reduced or eliminated to form a frontage smaller.;COPYRIGHT: (C)1994,JPO&Japio