Abstract: An installation for the treatment and further processing of thermoplastics comprises a screw-type compounding unit, downstream of which is disposed an intermittently drivable processing unit. Provision is made for a control unit which is connected with a drive of the screw-type compounding unit and with the drive of a metering device and with a drive of the processing unit. The control unit is designed for triggering the drives by the cycle time of the processing unit, the drives having identical run-up times and identical deceleration times.

Abstract: A method of preparing filled, modified and fiber reinforced thermoplastics is distinguished by the fact that polymer as matrix material together with blend polymer is fed to a twin screw extruder in a single manufacturing process, filler being supplied through a feeder device after the melting. Then fiber rovings are fed in and cut into long fiber sections in a fiber incorporation zone.

Abstract: A pelletizer comprises a knife head, which is mounted by a denture coupling on a rotatably drivable shaft. The denture coupling comprises at least one serrated ring mounted on the knife head and on the shaft, respectively, the serrated rings having a frontal tooth system and intermeshing. Furthermore, a chucking arrangement of the type of a collect chuck is provided for releasably locking the knife head and the shaft in the direction of their axis.

Abstract: A twin screw extruder has a casing with a working direction, two partially intersecting casing bores, which are parallel to each other, two shafts, which are disposed in the casing bores and which are drivable to rotate in the same direction of rotation about an axis of rotation, the axes of rotation having a distance A from each other, and single-flight kneading disks, which are fixed on the shafts and have surface lines extending parallel to the respective axis of rotation. The kneading disks, in a cross-section perpendicular to the axis of rotation, have a crest, which is formed as a segment of a circle about the respective axis of rotation and which has a crest angle b and a radius RA, a bottom, which is formed as a segment of a circle about the respective axis of rotation and has a bottom angle g and a radius RI and two flanks, which join the crest and the bottom, RA>RI, A≈RA+RI and 0°≦b≦45° applying.

Abstract: There is provided a multi-shaft kneading disc, kneading disc block, and a multi-shaft extruder containing the same. The kneading disc and each kneading disc in the kneading disc block having a disc shape with a central section defining an extruder shaft mounting bore and at least one lobe extending radially from said central section and having a crest end. The at least one lobe has a radius X which defines an outer diameter of the kneading disc. The central section has a radius Y which defines an inner diameter of the kneading disc. At least one other lobe extends radially from the central section and has a radius Z. The radius Z defines the outer diameter of at least one other lobe. The radius Z of the other lobe is equal to Y+⅞(X−Y) to Y+¼(X−Y).

Abstract: A mixing element for a screw extruder comprises an element including opposing lobes and a central portion having common opposing broad surfaces; one lobe broad surface being formed into a taper. The elements may be used individually or combined in blocks, with the elements of a block oriented in various combinations. The blocks may comprise two or more elements. The tapered lobes provided reduced pressure and temperature of the process as compared to prior art mixing elements. Also, more graduated control over temperature and pressure are provided according to the value of the taper magnitude, the number of elements used in a process and the relative lobe orientations in a machine.

Abstract: A single flighted multi-screw conveying bushing that has only one helical screw element extending the length of the bushing. The bushing has a cross-section shape that has a segmented circular base and a lobe extending from the base. The lobe has a truncated crest that is sized to have a circumferential angle of from 15.degree. to 30.degree. and preferably from 22.degree. to 24.degree.. Also, a twin screw extruder having a pair of side by side drive shafts with at least two of the single flighted screw bushings mounted end to end on each shaft.

Abstract: A multi-shaft screw-type extruder having a casing with two parallel intersecting casing bores and two shafts drivably disposed in the casing bores. Screw elements intermeshing kneading disks are fixed on the shafts The widths of the respective crest portions of the kneading disks are smaller than the disk width and form mixing-and-scraping-studs on the periphery of the disks. The mixing-and-scraping-studs on each kneading disk are axially misaligned relative to each other such that their peripheral faying surfaces jointly cover the entire disk width.

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.

Abstract: A screw extruder mechanism for the processing of strongly outgassing materials comprises a main extruder for proper material processing, a material feed and discharge device and a degassing device on the main extruder for the discharge of the gas stream from the portion of evaporation. For the gas stream to branch into at least three separate streams, the degassing device comprises a first degassing port and at least two degassing elements which are opposed radially to each other in relation to the main extruder and are disposed between the portion of evaporation and the first degassing port and which are designed preferably as ancillary screw extruders opening radially into the main extruder.

Abstract: In a screw-type extrusion machine comprising a composite casing which comprises casing sections fitted together in a longitudinal direction, the casing sections being tightly tautened relative to each other by a plurality of tie rods which extend parallel to each other in the longitudinal direction of the casing on the outside thereof, it is provided with a view to avoiding any over-stressing of the tie rods in the hot condition and to avoiding any leakage between the casing sections in the case of low temperatures and non-uniform temperature distribution, that the tie rods are loaded in the longitudinal direction by a pre-stressed spring system.