MOLDING APPARATUS WITH MOLD BLOCKS HAVING FACE ADJUSTMENT

摘要

A pipe molding apparatus includes a plurality of mold blocks which move along a molding path to form double wall plastic pipe having an outer pipe wall with corrugations which set outside diameter of the pipe and an inner wall around a bore through the pipe. The mold blocks have profiled faces which determine shape of the pipe. The profiled faces are reconfigureable in profile between first and second face profiles to vary both depth of the corrugations and diameter of the bore through the pipe without varying external diameter and while maintaining essentially constant wall thickness of the pipe.