| 摘要 |
PURPOSE:To form continuously a corrugated pipe whose inside is smooth and outside is provided with a spiral protruded stripe, by a method wherein a belt is molded continuously by a protruded part, the belt with the protruded part is wound spirally without causing deformation of a bent protruded part, and pressure welding and fusion adherence of its plane parts are done by piling them mutually. CONSTITUTION:A belt A with a protruded part having a bent protruded part D on some part is molded continuously by a method wherein a tape B made of thermoplastic resin is supplied to a circumferential face of an imaginary cylindrical rotary shaft body 1 along a spiral direction at an inclined angle running parallel with a spiral protruded stripe 6 and wound, and at the same time the tape B wound beforehand and the tape B wound afterward are made to wound so that they do not overlap each other and are welded through pressure by a pressing roll 13. Then the belt A with the protruded part is led on an imaginary cylindrical rotary shaft body 10 touched to the tip part of the imaginary cylindrical rotary shaft body 1, it is made to wind spirally by so preparing that bent protruded part D of the belt A wound afterward is overlapped on a plane part of the belt A wound beforehand, pressed by a pressing roll 14, and received while the mutual belts A are being cooled and hardened by making pressure welding and fusion welding of the mutual belts A. |
