Spiral distributor, die head, blown film line, and method for manufacturing a blown film

摘要

A spiral distributor for a die head of a foil extrusion line has spiral channels provided with shortening sections in their backward area. As compared to a geometrical rule for a discontinuation of the spiral channels which is valid in a prior section of the spiral channels, this arrangement leads to a faster discontinuation of the spiral channels. The design of the backward area of the spiral channels does not affect the good overlaying effect of the front part of the spiral channels. As compared to the customary embodiment, the channels are thus equipped with a less profiled backward end which leads to a more cost-effective manufacture and to a lesser flow resistance.