Vorrichtung und Verfahren zur Herstellung selbstreinigender Folien im Blasverfahren

摘要

An arrangement for producing film tubes (3) with a self cleansing surface, comprises an extruder (1) where a plastic melt is prepared, a moulding head (2) with a ring shaped outlet gap, and a squeezing section (4). A measurement unit monitors the number of raised sections (10) over a given surface area or length, and consists of a camera and an electromagnetic radiation source. The thickness of the extruded film is measured using a capacitative sensor and an optical sensor. The latter examines the reflected or absorbed light. A control unit stores threshold values for the measured values, so that comparisons can be made.