WELDING SLEEVE AND ITS PRODUCTION

摘要

PURPOSE: To obtain an economical fusion sleeve capable of obtaining stable operability at various environmental temps. at the time of fusion by providing a resistance winding to the inner surface of a sleeve member formed from a thermoplastic material. CONSTITUTION: A reinforcing ring 6 is arranged to the outer periphery 5 of a sleeve member 1 and bonded to the sleeve member 1 by a friction bonding method due to contraction or pressurization. The reinforcing ring 6 is heated to be pressed to the periphery of the sleeve member 1 and rapidly cooled thereafter. Whereupon, additional contraction stress is fixed to remain until a fusion process related to a pipe part and can be subsequently utilized perfectly in order to obtain fusion pressure. The reinforcing ring 6 is pressed to the sleeve member 1 when mounted on the sleeve member 1. At this time, the sleeve member 1 is already equipped with a resistance winding 3.