| 摘要 |
PURPOSE:To increase a haul-off speed by stabilizing a film and reducing a frictional resistance by a method wherein the second cooling ring is provided under a folding device and cooling wind is blown into a specified direction to blow air in-between a folding plate and the film. CONSTITUTION:A tubular film extruded upwardly from an annular head 2 is cooled by the first cooling ring 4 and expanded in a diameter thereof to make it into a baloon 3. The baloon 3 is cooled and stabilized by cooling wind blown from the second cooling ring 6 provided a little bit below folding plates 5 into a proceeding direction of the baloon 3 obliquely and upwardly. Simultaneously, a frictional resistance between the folding plates 5 and the baloon 3 is reduced by air blown into a space therebetween and the baloon 3 is folded along with the folding plates 5, thereafter, is hauled off through a nipple roller 7. For further details, a blowing angle of the cooling wind from the second ring 6 is preferably 30-90 deg. and an opening angle alpha of the folding plates 5, 5 is preferably 20-40 deg. respectively. |
