| 摘要 |
PURPOSE:To easily cool the inflation film extruded from an extrusion mold in the optimum state corresponding to a product size. CONSTITUTION:A cooling device consists of an upper mold 2, a lower mold 4, the low annular ring 5 provided to the lower mold 4, the upper annular ring 5 attached to the upper mold 2 in a replaceable manner and formed into a shape whose inner diameter La is larger than or equal to the inner diameter L of the lower ring 5 and the intermediate annular ring 6 attached to the lower ring 5 in a replaceable manner and a cooling air blowoff port 7 is formed by the upper ring 3 and the intermediate ring 6 or the upper ring and the lower ring and a plurality of cooling air blowoff ports having different inner diameters are formed by replacing the upper ring 3 and the intermediate ring 6. |
