PIPE EXTRUSION DIE AND RESIN PIPE

摘要

A pipe molding die of the present invention is capable of rectifying a flow of a molten resin by a resin reservoir and uniformizing the flow of the resin extruded from the die in whichever position in a peripheral direction on a flow path within the die. Consequently, ununiformity in wall thickness of the resin pipe to be molded can be eliminated. The pipe molding die comprises a throttle part as one of components thereof, which includes a core, a shell part fitted to the core and a resin reservoir as a portion of a flow path which is formed between the core and the shell part. A molten resin as a pipe raw material flows through the flow path. The resin reservoir is provided in at least one of the core and the shell part, and takes a ring-like shape circumscribing a central axis of the pipe molding die with the central axis centered. The resin reservoir assumes a recessed shape in cross-section.