Abstract: Numerous aspects concerning a blow film system are improved by the present invention.

Abstract: In a first phase, after completion of a production process for plastic films, the blowing head is heated by the heater that is present to a temperature above the melting temperature of the plastic remaining in the blowing head to liquefy the same. In a second phase, at the latest after the liquefied plastic has run out, at least the region of the blowing head that is in contact with the plastic is sealed off from the ambient atmosphere and purged of its oxygen-containing atmosphere. The head is then heated far above the decomposition temperature of the plastic still remaining, and the gaseous products thereby occurring are discharged. At the end of the decomposition phase of the remaining plastic, the blowing head is flushed through with a gas which contains at least a proportion of oxygen, in order to carry out an incineration of residual particles.

Abstract: A screw extrusion press for processing thermoplastic and not reticulating polymers comprises a conveying screw (1) in a cylinder (2). The screw comprises a conveying zone (7) and a mixing zone with 10 mixing rings (3). These mixing rings comprise a passage hole (5) that extends from the bottom (10) of the screw to the vicinity of the cylinder wall (20) where it opens out into a shear gap (9).

Abstract: The transporting roller, which serves for transporting a web of material which is wound up onto a winding shaft, is provided with a cutting device, which comprises a cutter and a cutter holder. The transporting roller has a groove, in which the cutter is guided. A catching device permits the introduction of the cutter into the groove. The groove is inclined with respect to an axially parallel generatrix, so that the web of material is cut off at an oblique angle.

Abstract: A lay-flat device of a blown film extrusion installation includes brush rollers in the upper half entirely or partly. The brush rollers include bristles which are directed obliquely outwards and which, on contact with an extruded film tube, exert a slight spreading force on the film, by which folding is avoided.

Abstract: The apparatus for handling a finished roll and a winding shaft on a winding apparatus for webs of material is configured with spaced apart rails pivotal independently from one another between a winding station and a setting-down station. Each of the rails supports a carriage operative to support the winding shaft and release it upon pivoting the rails towards the setting-down station, where at least one of rails pivots away from the winding shaft so as to facilitate removal of the roll from the shaft.

Abstract: An air turning bar for a take-off device for plastic films has a hollow cylindrical body having a depression in the region of the bar around which the film is wrapped. The remaining region of the bar is circular cylindrical. Air outlet openings are provided within the depression. Narrow circular cylindrical strips adjoin the ends of the depression which are provided in the longitudinal direction of the air turning bar.

Abstract: The air turning bar for a take-off device for plastic films has a hollow cylindrical body (1) having a depression (2) in the wrapping region of the film. The remaining region (6) is circular cylindrical. Air outlet openings (3) are provided within the depression (2). Narrow circular cylindrical strips (4) adjoin the ends of the depression (2) which are provided in the longitudinal direction of the air turning bar (1).