| 摘要 |
PURPOSE:To constitute the above method so that the surface is free from unevenness locally and accuracy in an inner circumferential length or straightness of an outer circumferential surface is made favourable. CONSTITUTION:A heat-resistant resin pipe 3 having the higher coefficient of thermal expansion than that of a steel pipe 2 is arranged within the steel pipe 2 whose inner circumferential surface is formed on a transfer surface, at least the resin pipe 3 and a thermoplastic sheet 1 are heated under a state where the thermoplastic sheet 1 molded in a state of an endless belt is arranged on the outer circumference of the resin pipe 3 and not only softening of the thermoplastic sheet 1 but also expanding of the resin pipe 3 are performed by the heating. The outer circumferential surface of the thermoplastic sheet 1 of the outer circumferential surface of the resin pipe 3 is pressure-contacted to the inner circumferential surface of the steel pipe and the inner circumferential surface of the steel pipe 2 is transferred to the outer circumferential surface of the thermoplastic sheet 1. |
