An assembly for processing viscous material comprises a process duct extending along a longitudinal axis, wherein viscous material advances in one advancing direction, at least one pumping device provided with a stator comprising a cylindrical seat, and at least one cylindrical rotor. The at least one cylindrical rotor is housed in the stator and is coupled to the stator with a sliding seal. The rotor rotates around a rotating axis substantially parallel to the longitudinal axis and has an outer face with at least one groove, which forms with the inner surface of the stator one pumping channel. The pumping device is configured so that the pumping channel extends between at least one inlet and at least one outlet and the inlet and the outlet are in fluid connection with the process duct.

The invention relates to a screw extruder (29) having a housing (30) comprising an intake housing (4), a degassing housing (5), and at least one housing bore (21, 22) running in the interior of the degassing housing (5) and implementing at least one internal wall segment (25; 26; 27; 28) of the degassing housing (5) and serving for receiving at least one auger shaft (7), and wherein the at least one wall segment (25; 26; 27; 28) of the at least one housing bore (21, 22) comprises at least one partition wall (13, 33) protruding into the at least one housing bore (21, 22) in the region of the degassing housing (5), and wherein at least one filter element (8) is disposed in the interior of the degassing housing (5) and at least partially encompasses the at least one auger shaft (7) and bears on the partition wall (13) in regions for implementing at least two spatial pressure regions (11, 12) sealed off from each other.

Methods for extrusion of polyolefins (112 ) that control specific energy input to the extruder (102 ) for gel reduction. Disclosed herein is an example method for forming plastic products (120, 208 ) with reduced gels, comprising: melting a polyolefin resin (112 ) in extruder (102 ) to form a melt; adjusting specific energy input in the extruder (102 ) to reduce gels in the melt; and forming the melt into a polyolefin product (120, 208 ). Disclosed herein is also an example method for forming plastic products (120, 20 ) with reduced gels, comprising: melting a polyolefin resin in extruder (102 ) to form a melt; selecting a throttle valve (104 ) position for gel reduction; setting the throttle valve (104 ) at the selected throttle valve (104 ) position to restrict flow of the melt out of the extruder (102 ); and forming the melt into a polyolefin product (120, 208 ).

A method for obtaining and applying a sealing gasket element on a slide-valve sliding in a cavity of an apparatus for the recirculation and mixing of chemically reactive polymeric components, comprises the steps of: obtaining from an elastic-plastic material a precursor element of the seal element, with a grid structure having a reticular shape; positioning the precursor element around the slide-valve; exerting on the precursor element, through temporary clamping elements, a radial compression and contraction action to insert it and couple it to one or more housing seats provided on the slide-valve so as to obtain the seal element well coupled to the latter; progressively removing the clamping elements to sequentially release successive parts of the gasket element and gradually free the slide-valve to gradually introduce the parts of the slide-valve—freed in succession—in the housing cavity allowing the sealing gasket element to gradually expand radially due to the elastic return by adhering tightly to the inner surface of the same housing cavity. The special equipment for fitting the sealing gasket element on the slide-valve and the so obtained recirculation and mixing apparatus is also described.

An extruder is provided with: a screw rotationally driven about the axis by a first motor; a barrel having a screw hole into which the screw is inserted and a de-airing port configured to discharge air inside the screw hole; a filter configured such that a part thereof faces the de-airing port of the barrel; and a filter-driving mechanism configured to move the filter to shift the part of the filter facing the de-airing port.

Disclosed is a flame-retardant HIPS material and a preparation method thereof, comprising the following components: 90 parts to 67 parts of a HIPS resin; 8 parts to 15 parts of a brominated flame retardant; and 3 parts to 7 parts of an auxiliary flame retardant; wherein the auxiliary flame retardant is a 1,3,5-triazine compound. In the present invention, a synergistic compounding of the brominated flame retardant and the auxiliary flame retardant effectively reduces an amount of the brominated flame retardant, and a stable UL 94 (1.5 mm) V-0 flame-retardant class can be achieved. Compared with the existing brominated flame-retardant HIPS, the present invention has a low halogen content, low gas, and high cost performance ratio, which avoids excessive acid gas from forming air lines on the surface of parts, has a good appearance.

A dry granulation process using a twin-screw extruder for granulating a powder mixture which includes at least one active ingredient and at least one carrier. The process includes steps of kneading the powder mixture in the screw barrel of the twin-screw extruder at a barrel temperature below a melting point of the at least one active ingredient and a melting point or a glass transition temperature of the at least one carrier to provide a kneaded powder mixture, and extruding the kneaded powder mixture to form granules. Granules and tablets produced using the dry granulation process in the twin-screw extruder are also provided.

On a rotary screen filtering device for medium to high-viscosity fluids, which comprises a rotary screen mounted for rotation in a housing, which screen has at least one screen element through which fluid can flow, the rotary screen, in the region of its sealing faces and the intermediate plates are fabricated or machined together so that they are of identical height. A gap width compensation layer is then inserted between the inlet plate and the intermediate plate and/or between the outlet plate and the intermediate plate. The package of plates is then pretensioned by means of screw bolts in such a manner that all the plates lie firmly against one another up to a maximum permissible operating pressure. Lubrication gaps of defined width are created between the sealing faces and the opposing inner faces of the inlet and outlet plates.

Kneading elements, extrusion apparatus, and methods of manufacturing honeycomb bodies are described herein. A kneading element (1802) has an inner surface (1804) defining an opening (1806) configured to couple the kneading element (1802) to a shaft (46,48). The kneading element (1802) also has a continuous closed curve elliptical outer surface (1808). The opening (1806) has an axis (1814) that is off-center with respect to a geometric center (1816) of the kneading element (1802) as viewed in a transverse plane perpendicular to the axis.

A hopper charged with a powder material, a screw arranged below the hopper and exposed at a supply port formed at the bottom of the hopper, and a rolling element in contact with the screw at the supply port are provided. The rolling element is larger than a space between end portions of the supply port and a screw groove of the screw.