Innenkühlung für aus einem Blaskopf extrudierte Kunststoffschlauchfolie

摘要

Proposed for a plastics tubular film (1) extruded from a blowing head is an inner cooling in which a plurality of cooling rings (5) are arranged at a distance from one another downstream of the blowing head in the direction of extrusion, which rings in each case have an annularly extending nozzle clearance, from which cooling air emerges. The cooling air initially emerges from the nozzle clearance (6) at an acute angle with respect to the axis of the tubular film (1) and in the direction of movement of the latter, subsequently flows parallel to the film (1) and in the axial direction with respect to the end face of the cooling ring and then enters into a further annularly extending nozzle clearance (7), cooling air being returned again within the cooling ring (5) to the first nozzle clearance (6).