Internally stacked blown film die.

摘要

A multi-layer annular die (40) is disclosed that permits the simple interchange of layer structure and change in layer numbers. The die (40) is equipped with a series of essentially identical feed modules (60) in which all axial passages of similar function are located at the same distance from the arial centerline and are also separated by a common angular spacing. Changes in the number of layers is accomplished by altering the number of feed modules (60), while alteration of layer structure brought about by rotation of the feed modules. Unlike prior stackable dies, resin flow is essentially radially outward from the die centerline to the discharge plenum, and all resin inlets are at a common height in the die base (41). <IMAGE>