| 摘要 |
PURPOSE:To improve workability, lower lining cost and, at the same time, realize inner surface covering excellent in wear resistance by a method wherein resin having shape memory characteristics as outside layer and resin excellent in wear resistance as inside layer are laminated to each other. CONSTITUTION:Two-layered tube is produced by laminating resin 2 having shape memory properties such as polyester resin, styrene-butadiene resin or the like as outside layer and resin 1 excellent in wear resistance such as styrene- butadiene rubber, natural rubber or the like as inside layer to each other. The tube concerned is produced by diametrically reducing two-layered tube, which is delovered from an extruder and cooled by water, with rolls and its shape is fixed by water cooling. After the diametrically reduced two-layered tube is inserted in steel pipe 3 for piping, hot air is blown in the resin tube for heating so as to let the resin tube restore its shape in order to obtain the inner surface covered tube, the lining of which is performed in the form closely contacting with the steel pipe. |
