Abstract: A screw to be used in an extruder, in particular in a single-screw extruder or a multiple screw extruder. The screw includes a spindle and a plurality of segments supported by the spindle and mutually arranged axially with sealed segment boundaries. A separate moment bridge is disposed between a first segment and an axially adjacent second segment. The moment bridge is configured to transfer a moment over the segment boundary from the first segment to the second segment.

Abstract: The invention relates to a method and an apparatus for producing a film web made of thermoplastic material in which the thermoplastic material is extruded in at least one layer as plastic melt from a wide-slit nozzle in an extrusion direction and subsequently led away over at least roller, wherein tensile forces are exerted in the extrusion direction and transversely to the extrusion direction in order to stretch the film web longitudinally and transversely, wherein during application of the tensile forces in and transversely to the extrusion direction the film web has a temperature at least corresponding to the melting temperature of the same.

Abstract: 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.

Abstract: Foil extrusion lines use spiral distributors for producing a melt which is as homogeneous as possible during operation. The spiral distributors are mostly available as cylindrical or conical axial spiral distributors or as radial spiral distributors. The spiral distributors have spiral channels that run in a multiple spiral arrangement so that rather flat horizontal edges are formed precisely in initial sections and vertical edges are formed between the beginning of spiral channels and transition sections of adjacent spiral channels. The melt can easily adhere there. To accelerate the melt in critical areas, the course or the cross-section of the channels or the surface are modified.

Abstract: The invention relates to a method and an apparatus for producing a film web made of thermoplastic material in which the thermoplastic material is extruded in at least one layer as plastic melt from a wide-slit nozzle in an extrusion direction and subsequently led away over at least roller, wherein tensile forces are exerted in the extrusion direction and transversely to the extrusion direction in order to stretch the film web longitudinally and transversely, wherein during application of the tensile forces in and transversely to the extrusion direction the film web has a temperature at least corresponding to the melting temperature of the same.

Abstract: A method for manufacturing a film that is provided with markings and is based on a thermoplastic plastic. The thermoplastic plastic is melted in an extruder and emerges from an extrusion die in the form of a melt web. The melt web is conveyed away over a surface of at least one cooling roller and cooled to produce the film. In subregions of the surface of the at least one cooling roller corresponding to the markings, the melt web and/or the film being produced from it is acted on with a different cooling action than in a remainder of the surface.

Abstract: Spiral distributors for plastic melt are often used for manufacturing foils in blown film extrusion lines. They overlie several partial flows of melt on their way to the ring-shaped outlet nozzle. The spiral distributors are designed either as cylindrical or truncated cone-shaped axial spiral distributors or as plate-shaped radial spiral distributors. In an axial spiral distributor several spiral channels are disposed as a multiple screw. In the case of a radial spiral distributor, several spiral channels are disposed as multiple spirals. The invention proposes to provide the spiral channels 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 leads to a faster discontinuation of the spiral channels. The invention has observed that 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.

Abstract: Foil extrusion lines use spiral distributors for producing a melt which is as homogeneous as possible during operation. The spiral distributors are mostly available as cylindrical or conical axial spiral distributors or as radial spiral distributors. The spiral distributors have spiral channels. These run in a multiple spiral arrangement so that rather flat horizontal edges are formed precisely in initial sections and vertical edges are formed between the beginning of spiral channels and transition sections of adjacent spiral channels. The melt can easily adhere there. The invention proposes to provide acceleration means for the melt in critical areas. For this, the invention provides for instance for a modification of the course or the cross-section of the channels or the surface.

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

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 invention relates to spiral distributors on axial or conical spiral blow heads. The invention has discovered that when the circumference of a spiral flock in a spiral mandrel slot increases, it can be advantageous if the height of the spirals can be limited in such a manner that a similar surface covered with spirals is created in the twisted mandrel slots. The invention calls this surface “active surface”. A plurality of aspects of the invention, which specify different rules regarding how to implement the basic observation, are presented.

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

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 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: 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.