Method and device for producing a pipe member

摘要

An object of the present invention is to provide a method for producing a pipe, which is capable of reducing the amount of thermoplastic material, without complicating an device for producing a pipe. The present invention provides a method for producing a pipe, comprising a thermoplastic material filling process for filling a die with a thermoplastic material, and a thermoplastic material discharging process for pushing out an unsolidified part of the thermoplastic material in the molding die using pressurized fluid, wherein the thermoplastic material is mixed with a foaming agent, the method further comprises a process for foaming the thermoplastic material filling the molding die, and the thermoplastic material discharging process is a process for pushing out a inner part of the thermoplastic material foamed in the molding die, by using the pressurized fluid prior to solidification of the inner part.

主权项

1. A method for producing a pipe member, comprising:
filling a molding die with a thermoplastic material containing a foaming agent; foaming the thermoplastic material in the molding die while controlling pressure and temperature conditions inside the molding die to provide a foamed core layer and a non-foamed skin layer; and discharging an unsolidified part of the thermoplastic material from the molding die by introducing or flowing pressurized fluid into the thermoplastic material in the molding die prior to a solidification of the core layer and using the pressurized fluid directly contacting the unsolidified thermoplastic material to push the unsolidified thermoplastic material out of the molding die and out of the skin layer.