| 摘要 |
<p>Cooling apparatus for air-cooling tubular plastic film which has been extruded from a film blowing head comprises spaced apart cooling rings, which in the direction of extrusion succeed the annular extrusion die of the film blowing head and are substantially concentric to the axis of the extruded tubular film and have air-guiding surfaces facing the surface of the tubular film and define annular nozzle gaps for delivering cooling air, which flows in contact with said air-guiding surfaces. The airguiding surfaces are convexly curved in a longitudinal sectional view of the cooling rings. The nozzle gaps are defined by rings which in the direction of flow of the cooling air precede the cooling rings and which are so arranged that the cooling air discharged from said nozzle gaps flows in a direction which is approximately parallel or at an acute angle to the direction of travel of the tubular film.</p> |
