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: A material processing plant consists of a first screw-type machine and a second screw-type machine: The screw-type machines are connected to each other by means of a pipe elbow. An elongation compensation device is disposed between the first screw-type machine and the pipe elbow. An expansion compensation device for thermal expansion of the second screw-type machine is disposed inside the last column of the first screw-type machine which is arranged upstream of the pipe elbow.

Abstract: A drive unit for a twin-screw machine, of which the screw shafts, which can be driven in rotation in the same direction, have an axial spacing a, has two output shafts. The output shafts are provided with a respective crown gear which does not collide with the adjacent output shaft. The drive motor provided is in the form of a torque motor having a stator housing, a rotor, which is rotatably arranged in the stator housing, and at both ends of the rotor, outside the stator housing, a drive pinion meshing with a crown gear.