A screw element (100) for an extrusion machine is provided. The screw element (100) includes a first section (200) and a second section. The first section (200 has a first core (212) with a plurality of facets (214) connected to each other along splines (216). The facets (214) and splines (216) extend longitudinally along the screw element (100). The facets (214) and splines (216) can be helically-shaped. The first core (212) increases in diameter in a continuous manner along the direction of flow of material. The first and second sections (200, 300) include one or more helically-shaped flights (218,219) wrapped around the longitudinal axis of the screw element (100).

A polymer melt candle filter having a support which comprises a hollow cylindrical body defined by a first end, a second end, and a cylinder wall having a first end portion and a second end portion. The first end portion includes a screw thread on its outside surface and optionally a hex fitting on its inside surface for receiving a hex wrench. The second end portion includes a plurality of holes in the cylinder wall. The area of the openings of the holes on the outside surface of the cylinder wall may be larger than the area of the openings of the corresponding holes on the inside surface of the cylinder wall. The shape of the openings of the holes on the outside surface may be non-circular. A polymer melt filter plate assembly which comprises (a) a support plate comprising a plurality of threaded holes; (b) at least one filter which is screwed into at least one of the threaded holes via the screw thread on the outside surface of the first end portion of the filter support; (c) a tie rod with (i) a first end extending through a hole in a cone insert and a cap located at the second end of the filter support, and (ii) a second end extending through a threaded hole in the support plate; and (d) a cross bar which is attached to the second end of the tie rod for holding the support plate inside a shaft of an apparatus for filtering a polymer melt.

The present invention relates to a seal device for a negative pressure calibrating unit in a extrusion line for producing profiled plastic sections, in particular pipes whereby the inner face of a seal rests against the circumference of the extruded profiled section in a formfitting manner and the seal is radially supported on the profiled section in order to apply a sealing force. It is the object of the invention to provide another similar device which is very easily constructed and can be produced inexpensively. This task is solved in that the seal is a porous and elastic foam body (13), the surfaces (17, 19) of that are exposed to the atmosphere are coated with an air-tight coating (21).

A polymer melt candle filter having a support which comprises a hollow cylindrical body defined by a first end, a second end, and a cylinder wall having a first end portion and a second end portion. The first end portion includes a screw thread on its outside surface and optionally a hex fitting on its inside surface for receiving a hex wrench. The second end portion includes a plurality of holes in the cylinder wall. The area of the openings of the holes on the outside surface of the cylinder wall may be larger than the area of the openings of the corresponding holes on the inside surface of the cylinder wall. The shape of the openings of the holes on the outside surface may be non-circular. A polymer melt filter plate assembly which comprises (a) a support plate comprising a plurality of threaded holes; (b) at least one filter which is screwed into at least one of the threaded holes via the screw thread on the outside surface of the first end portion of the filter support; (c) a tie rod with (i) a first end extending through a hole in a cone insert and a cap located at the second end of the filter support, and (ii) a second end extending through a threaded hole in the support plate; and (d) a cross bar which is attached to the second end of the tie rod for holding the support plate inside a shaft of an apparatus for filtering a polymer melt.

The invention relates to a filter device for polymer melts, having a filter screen (1), through which the polymer melt to be purified is guided, wherein the filter device comprises at least one scraping element (2), which glides across the upstream surface (4) of the filter screen (1) with its scraping edge (3), or rests on the surface (4) with its end area nearest the scraping edge (3), and lifts off and/or scrapes off the contaminations (6) adhering to the surface (4) and those present in front of the screen orifices (5) in the course of its movement across the surface (4). According to the invention it is provided that the scraping edge (3) has a curvature (7) at least in the end area of the same, leading in the direction of movement (16), the radius (R) of which is less than 90%, preferably less than 50%, in particular less than 20% of the maximum diameter, or of the maximum orifice width of the screen orifices (5).

Calibration basket having exchangeable air guiding elements composed of porous material. The invention relates to a guiding device and to methods for guiding a plastic film, wherein the plastic film can be guided by means of an air cushion, wherein the guiding device comprises a plurality of blower elements (31) each having the foil owing features: at least one supporting element (35), at least one film-guiding element (34), which is at least partially porous, preferably microporous, and which is connected to the supporting element (35). At least one fastening element is provided, by means of which the supporting element (35) and the film-guiding element (34) can be detachably fastened to each other.

A device (1) for filtering plastic melt having an inlet valve (14), an outlet valve (15) and a filter canister (2), wherein a cavity (3) closable by means of a cover (4) is formed and into which a melt channel (20) opens. In the filter canister (2) there is arranged a plurality of filter cartridges (5), which are each formed by a filter substrate (6) and a filter lattice (7). The filter substrate (6) comprises a wall having openings, said wall defining an internal space (8), which opens through an outlet (9) into a collection channel (10). The filter lattice (7) covers the openings of the filter substrate (6). The melt channel (20) is adjacent to the inlet valve (14) and may be brought into fluid communication with an outlet channel (16) via the inlet valve (14). The collection channel (10) is adjacent to the outlet valve (15) and may be brought into fluid communication with an outlet channel (18) via the outlet valve (15). The cover (4) fixes the filter lattices (7) onto the filter substrates (6).

A calibration and cooling tank of an extrusion line, which connects to an extrusion tool, wherein a vacuum can be applied to the calibration and cooling tank for calibrating the plastic melt emerging from the extrusion tool, wherein the calibration and cooling tank extends along an extrusion axis. The calibration and cooling tank is modularly structured, wherein at least one module forms a calibration and cooling section and the module has a connection region on both sides to which an additional module can be attached. The connection region includes a flange that extends from the base element of the calibration and cooling tank to the outside.

A fiber reinforced polymer part is fabricated by rastering a deposition head over a substrate, and additively forming part features by extruding a polymer having an entrained continuous reinforcement from the deposition head onto a substrate.

A method is provided for fabricating a surface protection film that has no rolling defects such as blocking or wrinkling when rolled into a roll, and that, after the film is bonded to an adherend, is rolled into a roll, and stored for long periods of time, does not transfer unevenness or fisheyes on the back surface to the adherend. The surface protection film is fabricated as an elastomer by setting the arithmetical mean roughness (Ra) of the surface of a cold roller (4) to no more than 0.2 m, and the ten point mean roughness (Rz) of the surface of a nip roller (3) to 2-8 m and the mean distance (Sm) between protrusions and depressions thereof to no more than 90 m.