Pipe belling process

摘要

An improved pipe belling process is shown which features a mandrel having a specially designed backup or forming collar. The backup collar has an exposed lip portion which forms a complimentary angle with the outer sloped surface of the gasket which it abuts. The complimentary angles of the backup collar and gasket form a wedge shaped contact area which serves to retain the gasket in its initial circumferential position on the working surface of the mandrel as the heated pipe is forced over the mandrel and gasket.