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.

Abstract: A screw-type extruding machine includes a housing; a driveable shaft disposed inside the housing and including a rotational moment transfer element; and at least one screw element. The screw element has two ends and defines a longitudinal groove therein for receiving the rotational moment transfer element of the shaft, the shaft thereby transferring its rotational moment to the screw element. The groove is configured such that it defines two expansion regions, each expansion region having an axial extent, the groove having side surfaces which diverge with respect to a longitudinal axis of the groove along the axial extent of each expansion region in a direction toward a corresponding one of the two ends of the screw elements, a width of the groove thereby increasing in a direction toward its two ends along each expansion region.

Abstract: In an underwater pelletizing die plate or an extruder for the pelletizing of thermoplastics, the front face of the die plate, which is provided with a wearing protection layer and over which pass the pelletizing knives, being disposed under water, and heat isulation means being provided on the pelletizing die plate, good axial insulation is to be achieved, accompanied by uniform temperature distribution in the radial direction, it being provided to this end that an insulating layer is disposed between the external upper side of the actual pelletizing die plate and the wearing protection layer, the wearing protection layer being positioned, relative to the insulating layer, with radial play and without axial pressure or with little axial pressure, respectively.