| 摘要 |
PURPOSE:To get heat recovery tube with no change in length at thermal expansion and useful for coating inner surface of elongated article by treating thermoplastic resin into bridged structure and expanding in logitudianl direction at heating at approx softening temperature and then forming corrugate. CONSTITUTION:Thermoplastic resin 1 such as polyethylene is extruded by a tube extruder 2 and then cooled in a water tank 3. Then, electron beam is applied by an electron beam irradiator 4 to get bridged heat recovery resin 5. The resin is heated to approx softening temperature in a heat furnace and rolled between pinch-rollers 6, 9. Then, it is corrugated by a corrugate forming device 8 and heat recovery tube 10 is rolled up by a winch 11. Then it is expanded by heat to remove the corrugate A and get tube B after expansion. USE:Lining of inner surface of pipe such as steel. |
