MANUFACTURING APPARATUS AND MANUFACTURING METHOD FOR COMPOSITE PIPE, AND COMPOSITE PIPE

• Main Authors: HAGINO TOMOKAZU, ICHIHARA KOJI, KANEHIRA YUTAKA
• Format: Patent
• Language: English; Japanese
• Published: 16.09.2021
• Subjects: BLASTING; ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; JOINTS OR FITTINGS FOR PIPES; LIGHTING; MEANS FOR THERMAL INSULATION IN GENERAL; MECHANICAL ENGINEERING; PERFORMING OPERATIONS; PIPES; PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCESIN A PLASTIC STATE; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; THERMAL INSULATION IN GENERAL; TRANSPORTING; WEAPONS; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

To provide a composite pipe in which generation of abnormal noise can be suppressed without providing an intermediate layer of a foamed resin between an inner pipe and a corrugated pipe, and the corrugated pipe can be reliably formed by reliably supplying gas between the inner pipe and the corrugated pipe when the corrugated pipe is molded.SOLUTION: There is provided a manufacturing method of a composite pipe, in which: an inner pipe 9 is sent out from an inner pipe outlet 21 at a center of an extrusion nozzle 20 to a corrugated pipe forming portion 30; a resin 19 to be a corrugated pipe 10 is supplied to the extrusion nozzle 20 to extrude from an annular extrusion port 22 surrounding the inner pipe outlet 21 to the corrugated pipe forming portion 30; and an extruded tubular resin 19A is formed into a corrugated cross section by a corrugated mold surface 39. An inner circumference of the extrusion port 22 is larger than a smallest inscribed circle diameter on the corrugated mold surface 39, and a continuous airspace 18 is formed over an entire area in an axial direction between the corrugated pipe 10 and the inner pipe 9.SELECTED DRAWING: Figure 4 【課題】内管と波形管との間に発泡樹脂の中間層を設けることなく異音発生を抑制でき、かつ波形管の成形時には、内管と波形管との間に気体を確実に供給して、波形管を確実に成形できる複合管を提供する。【解決手段】内管９を、押出ノズル２０の中央部の内管送出口２１から波形管成形部３０へ送り出す。波形管１０となる樹脂１９を押出ノズル２０に供給して、内管送出口２１を囲む環状の押出し口２２から波形管成形部３０へ押し出す。押し出された管状の樹脂１９Ａを波形型面３９によって波形断面に成形する。押出し口２２の内周径は波形型面３９における最小の内接円径より大きい。波形管１０と内管９との間の軸方向の全域にわたって連続する通気隙間１８を形成する。【選択図】図４