| 摘要 |
PURPOSE:To provide a method of manufacturing a lining metal tube consisting of a metal tube and a synthetic resin tube which are firmly bonded together and therefore, are not separated from each other. CONSTITUTION:A space (b) of a specified width is provided between a V-bent preheating device 3 and a heating device 4, and a tubular product (a) heated upto a specified temperature level is allowed to cure in the space (b) during a period in which the tubular product (a) is passing through the preheating device 3. Thus the temperature of the periphery of the tubular product (2) is equalized. Next, the tubular product (a) is heated from the center to both ends using the heating device 4. Further, the outer or inner peripheral facing of a metal tube 1 is coated with a synthetic resin tube 2 which expands or contracts due to softening from the center to both ends. Finally, the both ends of the synthetic resin tube 2 is allowed to expand or contract toward the tubular end side by heating only an area near both ends of the tubular product (a) toward the tubular end side using a heater 5, so that the both end parts of the synthetic resin tube 2 comes into contact with the inner or outer peripheral facing of the end part of the metal tube 1. Consequently, a lining metal tube is obtained which consists of the metal tube firmly junctioned to the synthetic resin tube and never separated. |
