A device, to homogenise plastics material melts, has a homogenising element with a plurality of flow channels, which differ with respect to at least one feature from the group length, cross sectional area and cross sectional shape. When flowing through the homogenising element, the plastics material melt is divided into a plurality of part streams, which, in each case, flow through an associated flow channel. When leaving the respective flow channel the part streams have different flow speeds so the plastics material melt is expanded and sheared on transition to a uniform flow. As a result, a homogenisation of the plastics material melt takes place in a simple, efficient and effective manner.

In an embodiment, the present invention provides a pin extruder, including a screw conveyor for conveying plastics, the screw conveyor having a plurality of pins each arranged in a respective pin row, the pin rows being arranged in a plurality of consecutive planes in a conveying direction of the screw conveyor. A distance between the planes of at least individual pin rows varies in the conveying direction.

A twin-screw extrusion kneader includes: two rotating shafts provided side by side in an internal space; a rotational driving portion configured to rotationally drive the rotating shafts; and paddles provided in the rotating shafts and configured to rotate along with the rotating shafts so as to knead a kneading material. Further, the twin-screw extrusion kneader includes movable portions provided as members constituting a part of the housing, the part of the housing including an inner wall surface of the housing, the inner wall surface being opposed to radially outer peripheral surfaces of the paddles. The movable portions can be moved in a direction to approach the paddles and in a direction to be distanced from the paddles.

Processes for decrosslinking crosslinked plastic and devulcanizing vulcanized rubber include advancing such materials through single screw or twin screw extruders including special ultrasonic treatment zones wherein threadless shaft (single screw) or shafts (twin screw) rotate under an ultrasonic horn having a distal end aligned with the shaft or shafts and being shaped complimentary thereto. Special arcuate (single screw) or double-arcuate ultrasonic treatment flow paths confine the materials to flow under the horn where the material is subjected to ultrasonic waves to decrosslink the material, in the case of crosslinked plastic, or devulcanize the material, in the case of vulcanized rubber, with the extrudate leaving the die as a continuous stream or rope as is typical of virgin plastic or rubber.

Processes for decrosslinking crosslinked plastic and devulcanizing vulcanized rubber include advancing such materials through single screw or twin screw extruders including special ultrasonic treatment zones wherein threadless shaft (single screw) or shafts (twin screw) rotate under an ultrasonic horn having a distal end aligned with the shaft or shafts and being shaped complimentary thereto. Special arcuate (single screw) or double-arcuate ultrasonic treatment flow paths confine the materials to flow under the horn where the material is subjected to ultrasonic waves to decrosslink the material, in the case of crosslinked plastic, or devulcanize the material, in the case of vulcanized rubber, with the extrudate leaving the die as a continuous stream or rope as is typical of virgin plastic or rubber.

Melt pumps for producing synthetic granules, extruded profiles or molded parts are disclosed. One disclosed example melt pump for building up pressure at a fluid medium is to be used for pressing the medium through a tool. The example melt pump includes a compressor that comprises an inlet and an outlet opening, and at least two worm conveyors disposed in a common housing, where worm flights provided on the worm conveyors are configured in such a manner that a force feed of the medium occurs and where the worm conveyors are drivable by their own drive.

An extruder is disclosed, and more particularly, to an integrated single screw extruder and a twin screw extruder for mixing, compounding, kneading and/or extruding of materials. The integrated extruder includes a first barrel assembly and a second barrel assembly. The integrated extruder further includes a first screw having a first threaded portion and a second threaded portion. The first threaded portion is housed within the first barrel assembly and is configured to provide upstream material processing. The second threaded portion is housed within the second barrel assembly and is configured to provide downstream material processing. The integrated extruder further includes a second screw having a non-threaded shaft portion and a threaded portion. The threaded portion of the second screw is housed within the second barrel assembly and is configured to provide the downstream material processing with the second threaded portion of the first screw.

An extruder is disclosed, and more particularly, to an integrated single screw extruder and a twin screw extruder for mixing, compounding, kneading and/or extruding of materials. The integrated extruder includes a first barrel assembly and a second barrel assembly. The integrated extruder further includes a first screw having a first threaded portion and a second threaded portion. The first threaded portion is housed within the first barrel assembly and is configured to provide upstream material processing. The second threaded portion is housed within the second barrel assembly and is configured to provide downstream material processing. The integrated extruder further includes a second screw having a non-threaded shaft portion and a threaded portion. The threaded portion of the second screw is housed within the second barrel assembly and is configured to provide the downstream material processing with the second threaded portion of the first screw.

A conveyance portion, a barrier portion, and a path are provided at places of a portion of a screw main body in which a kneading portion is provided. In at least one of the places, an entrance is opened to cause raw materials, conveyance of which is limited by a barrier portion to increase pressure on the raw materials, to flow in. The raw materials flowing in from the entrance flow through the path in the opposite direction to a conveyance direction of the conveyance portion. An exit is opened in an outer circumferential surface of the screw main body at a position outside the conveyance portion in which the entrance is opened.