| 摘要 |
PURPOSE:The title device, designed to prevent the contact between a plastic tubing material and a heated pipe wall by an air flow and to expand the material without causing longitudinal elongation, wherein a heating and a cooling parts are of specific shapes. CONSTITUTION:The inside diameter of the heating part 3 is sufficiently larger than the outside diameter of the tubing material 1, and the inside diameter of the cooling part 2 is small to such an extent that the outside diameter of the tubing material 1 may be almost inscribed in the inside diameter. The inner wall of the cooling part 2 is provided with the sliding Teflon material 5. Cooling water is passed through the cooling part 2 to prevent the adhesion of the material 1 to the Teflon material 5. When the material 1 enters the heating part 3, the vacuum action of the expanding part 4 sucks the outside air from the slight gap between the cooling part 2 and the material 1 to produce an air flow in the heating part 3, thus preventing the adhesion of the material 1 to the heating pipe 9. The material 1 is then vacuum expanded in the expanding part 4. |
