| 摘要 |
PURPOSE:To prevent buckling due to driving force in the axial direction of a tubular body by a method wherein a thick rigid layer is laminated onto one surface of an inwall sheet to constitute a laminate, which is spirally wound successively onto a mandrel to form a cylindrical body, while a driving force in the axial direction is applied, an outside surface is supplied with a molten resin and a resin coating is shaped, and the tubular body is formed. CONSTITUTION:An inwall sheet 2 has multilayer constitution in which the layers 2a, 2f of a resin material such as a polypropylene resin are shaped on both sides of a metallic foil 2c such as an aluminum foil. One edge 2g of the inwall sheet 2 is heated by a hot air heater 3, and forwarded on a roll 4, and the edge of the metallic foil 2c is wrapped with a film material at said edge 2g. Such a laminate is brought to the state in which edges are superposed, and wound spirally onto a mandrel 25, thus forming a cylindrical body 26. When the laminate is wound spirally on the mandrel, a rigid layer is cured sufficiently, and the laminate has rigidity only of resistance against driving force in the axial direction applied to the cylindrical body. Accordingly, the buckling of the cylindrical body by driving force and out-of-shape are prevented. |
