| 摘要 |
PURPOSE:To obtain a flexible corrugated tube without lowering the inner surface property thereof, by spouting a silicone oil under specified conditions onto a corrugated mandrel that is being rotated so that the silicone oil may be applied thereon and the mandrel may be lubricated, while extruding a thermoplastic resin into the shape of a tube. CONSTITUTION:While a thermoplastic resin is extruded into the shape of a tube onto a corrugated mandrel 1 having a circumferentially helical corrugation section 3 that is being rotated, a vacuum is applied between the extruded resin tube and the mandrel 1, so that the resin tube is attracted onto the corrugation section 3 of the mandrel to be molded. In producing a flexible corrugated tube 2 by feeding the molded tube by the helical feeding action due to the rotation of the mandrel 1, a silicone oil is spouted in the form of fog at a spouting pressure of less than 4kg/cm<2> and a spouting amount of less than 0.1ml/min onto the corrugated mandrel 1 that is being rotated to lubricate the mandrel 1 to produce the aimed corrugated tube. |
