Abstract: An injection molding system, to produce fiber-reinforced plastics material parts, has an injection molding device with a housing and a housing bore formed therein. A screw shaft, which is rotatably drivable about a rotational axis and can be displaced along the rotational axis, is arranged in the housing bore to melt and introduce plastics material into a mold. For feeding fibers, the injection molding system furthermore has a feed device, which is configured in such a way that cut fibers can be fed through a feed opening directly into the housing bore. The injection molding system according to the invention allows simple and flexible production of fiber-reinforced plastics material parts.

Abstract: A feed device for feeding fibers during the production of fiber-reinforced plastics materials has a multi-shaft screw machine for the lateral guidance of the fibers into a preparation system for producing fiber-reinforced plastics materials. The multi-shaft screw machine comprises a housing, a plurality of housing bores penetrating one another as well as screw shafts, which are rotatably drivable and are arranged therein, and a feed opening. A suction mechanism, which produces an airstream sucking in the fibers, is provided to suck the fibers through the feed opening into the housing bores. The fibers are filtered by means of a filter mechanism out of the airstream. In order to ensure a long service life, the filter mechanism has a plurality of flow channels, which have a widening cross section in a flow direction.

Abstract: An injection molding system, to produce fiber-reinforced plastics material parts, has an injection molding device with a housing and a housing bore formed therein. A screw shaft, which is rotatably drivable about a rotational axis and can be displaced along the rotational axis, is arranged in the housing bore to melt and introduce plastics material into a mold. For feeding fibers, the injection molding system furthermore has a feed device, which is configured in such a way that cut fibers can be fed through a feed opening directly into the housing bore. The injection molding system according to the invention allows simple and flexible production of fiber-reinforced plastics material parts.

Abstract: A feed device for feeding fibers during the production of fiber-reinforced plastics materials has a multi-shaft screw machine for the lateral guidance of the fibers into a preparation system for producing fiber-reinforced plastics materials. The multi-shaft screw machine comprises a housing, a plurality of housing bores penetrating one another as well as screw shafts, which are rotatably drivable and are arranged therein, and a feed opening. A suction mechanism, which produces an airstream sucking in the fibers, is provided to suck the fibers through the feed opening into the housing bores. The fibers are filtered by means of a filter mechanism out of the airstream. In order to ensure a long service life, the filter mechanism has a plurality of flow channels, which have a widening cross section in a flow direction.

Abstract: The present invention relates to a process for producing a composite having a reduced electrical resistance which comprises providing a mixture comprising a fluid material and carbon nanotubes (CNTs) having a predeterminable size distribution, and subjecting the mixture to a minimum stress in a dispersing machine, wherein the minimum stress is determined empirically as a function of the predetermined size distribution.

Abstract: An extruder with a housing comprising parallel, partially inter-engaging bores and screws disposed therein is used when applying a method of feeding powdery bulk materials into such an extruder. A solid transport of powdery bulk material takes place in an inlet zone disposed downstream of a feed opening wherein said inlet zone is partially filled. The inlet zone is provided with at least one gas-permeable wall portion wherein a layer of bulk material is created on said wall portion, thereby preventing bulk material from passing through, The gas-permeable wall portion is connected to a vacuum source and to a pressure gas source. Furthermore, the gas-permeable wall portion has an inner wall which is set back with respect to the wall of the bores, thereby forming a gap with a partially annular cross section wherein a layer of the bulk material is formed in the gap.

Abstract: An extruder with a housing comprising parallel, partially inter-engaging bores and screws disposed therein is used when applying a method of feeding powdery bulk materials into such an extruder. A solid transport of powdery bulk material takes place in an inlet zone disposed downstream of a feed opening wherein said inlet zone is partially filled. The inlet zone is provided with at least one gas-permeable wall portion wherein a layer of bulk material is created on said wall portion, thereby preventing bulk material from passing through.

Abstract: A gear pump comprises a casing and gear rotors disposed therein. The gear rotors are lodged in bearing sections of plain bearings that are lubricated by the pumping medium. They have at least one cooling duct which is embodied such that cooling varies along the circumference and/or in the longitudinal direction and/or in the radial direction of the plain bearing.

Abstract: A gear pump comprises a casing (1) and gear rotors (2, 3) disposed therein. The gear rotors (2, 3) are lodged in bearing sections (15 to 18) of plain bearings (11 to 14) that are lubricated by the pumping medium. They have at least one cooling duct (39) which is embodied such that cooling varies along the circumference and/or in the longitudinal direction and/or in the radial direction of the plain bearing (11 to 14).

Abstract: In a method of carrying out continuous preparation processes on tightly meshing extruders rotating in the same sense such as twin-screw and multi-shaft screw-type extruders, the extruder is operated at a screw speed of rotation of at least 800 rpm, accompanied with a simultaneous increase of the so-called "torque density" (M.sub.d /a.sup.3) of at least 11 Nm/cm.sup.3 and a volumetric ratio (Da/Di) of at least 1.5.