| 摘要 |
PURPOSE:To enable the molding of the pipe of a continuous length, preventing the generation of a gum, by feeding a lubricant to a sliding face between a thermoplastic resin and a forming die provided with a mandrel and molding it pipe like. CONSTITUTION:A thin layer is formed by feeding a lubricant (e.g. polydimethylsiloxane) to a sliding face 6 between a molten thermoplastic resin 1 and a forming die 3 from a slit 10 shaped by the flanges 8, 9 of a lubricant feeding device 7 via a force-in pump at a higher pressure than the resin 1. Then the thermoplastic resin 1 melted, kneaded by an extruder is extruded pipe like through a clearance shaped by a die sleeve 2, a forming die 3 and a mandrel 4 and molded into a pipe 11, its outside being sized by a sizing device 5. |
