| 摘要 |
PURPOSE:To easily manufacture a heat-shrinkable tube having a large shrinkage factor by a reduced number of processes by interposing a rubber tube almost uniform in elongation in the peripheral direction thereof between a heating mandrel and a material tube to integrally heat the same along with the material tube and subsequently introducing a fluid in the rubber tube to expand the diameter of the material tube. CONSTITUTION:The outer periphery of a heating mandrel 12 is covered with a rubber tube G and a material tube W composed of a crosslinked thermoplastic resin is superposed on the rubber tube G to cover the tube G and, after the rubber tube G and the material tube W are integrally heated by the heating mandrel 12, a fluid, for example, air is introduced into the rubber tube G. By interposing the rubber tube G, the diameter of the material tube W is equally expanded even when the material tube W is irregular in wall thickness. |
