Patent ID: 9321195
Filing Date: 2016-04-26
CPC Classification: B29C,B29K,B29L

Claim Text:
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.