| 摘要 |
<p>PURPOSE:To enhance the strength of a resin layer, reduce the residual strain in diameter contraction and prevent buckling deformation in repeated cooling and heating by laminating a foamed thermoplastic resin layer and a reinforced layer comprising a thermoplastic resin and reinforcing fibers on the inside of a metallic pipe in sequence. CONSTITUTION:A fiber-resin composite tape, being made cylindrical, is led to a cylindrical extruding mold, and polyvinyl chloride is extruded by an extruder so that the inmost layer 1 is obtained. The fiber-resin composite tape is fused on the surface of the inmost layer to form the first reinforced layer 2 so that a two-layer pipe is obtained. The composite tape, being heated by a hot air generator, is wound up by a winder spirally at an inclination angle of 75 deg. to the axial direction of the two layer pipe to form the second reinforced layer 3, producing a three-layer pipe. The three-layer pipe led to a mold for coating a foam layer is coating-extruded by the second extruder to form a foam layer 4, obtaining a four-layer pipe. The four-layer pipe coated with an adhesive is inserted into a steel pipe as an inserted pipe.</p> |
