Process for forming a flange on a hollow body of thermoplastic material

摘要

A process and an apparatus for forming a flange on the wall portion of a hollow body of thermoplastic material with an opening at one end provides that the end part of the wall portion which defines the opening is heated and contracted by means of a force acting on the end portion from the outside thereof over the periphery thereof, whereupon the contracted end part is subjected to a pressing operation to form a flange extending around the contracted end part.