| 摘要 |
A thickness profile in the production of blown film is controlled and automatically controlled by supplying additional air streams in the direction of production in front of a main cooling ring. Controlling and automatically controlling the thickness profile in the production of blown film includes using blown film extruders; and scanning the film thickness of the blown film above a freezing zone in different circumferential regions and controlling the additional air streams as a function of the measured film thickness, by using a measuring and controlling device. The additional air streams are supplied in the direction of production in front of the main cooling ring. An independent claim is also included for a device for carrying out the above method, comprising blown film extruders having a blow head (1), a main cooling ring (2) for supplying a main cooling gas stream (3), and an additional cooling ring (4) arranged outside the main cooling ring and provided for supplying separate additional cooling air streams (5); and the above measuring and controlling device. The additional cooling ring is provided in the form of a segment disc and is arranged at the blow head of the extruder underneath the main cooling ring. |
