| 摘要 |
PURPOSE:To obtain the titled tube having no constriction or locally varied thickness and useful as a corrosion preventive layer or the like for an electric power cable connection part, by placing a raw tube coaxially in a molding pipe, heating them with the opposite ends sealed, and expanding molding the raw tube using compressed air by a special method. CONSTITUTION:A raw tube (for example: of vinyl chrolide, etc.) 2 is placed coaxially in a molding pipe 1 having an inner diameter equal to the outer diameter of the intended heat shrinkable tube, the opposite ends of the raw tube 2 and the molding pipe 1 are dismountably secured to caps 5, 6 or the like, are sealed, and then are heated. Pressurized fluid is filled from a fluid supply hose 8 into the space between the raw tube 2 and the molding pipe 1, and the pressurised fluid in the space is gradually evacuated through a discharge hose 9 to reduce the pressure in the space 13 while compressed air is charged vai an air hose connected to an open plug 3 at the upper end of the raw tube 2 into the raw tube 2 until the raw tube becomes in contact with the inner wall of the molding pipe so that the raw tube is expanded to be molded. |
