The present invention relates to a process for devolatilising polymer-containing media such as, in particular, polymer melts, polymer solutions and dispersions and also devolatilisation apparatuses for carrying out the abovementioned process.

Puck and collar alignment device embodiments facilitate simultaneous insertion of free end portions of screw shafts into open end portions of complementary drive couplings. The embodiments have alignment keys that correct deviations in alignment and rotation introduced while moving the screw shafts though a barrel of an extruder. Tapered front faces of the alignment keys incrementally adjust coaxial alignment, and tapered side faces of the alignment keys incrementally adjust rotational position cooperatively between the alignment devices and drive couplings. The coaxial and rotational position adjustments cooperate to simultaneously guide multiple alignment keys to fit within corresponding keyway sections while providing alignment of external splines on the screw shafts to interlock in a timed relationship with internal splines on the drive couplings during the simultaneous insertion.

A kneading apparatus having a kneading unit made up of a plurality of segment parts detachably mounted on a shaft disposed in the barrel includes a first segment part having a first length L1 related to an outer diameter D, a second segment part having a second length L2 shorter than the first length L1, and a third segment part having a third length L3 longer than the first length L1; the first length L1 is [the outer diameter Da coefficient a]; the second length L2 is [the first length L1/a coefficient b]; the third length L3 is [the first length L1the coefficient b]; the third length L3 is [L1+L2]; and the kneading unit has a segment pattern made up of a plurality of segment parts and mounted on the shaft interchangeably with another segment pattern.

An extruder screw including an elongated cylindrical tension rod; screw segments including radially protruding functional elements configured to feed, mix, and/or knead an extrudate, and a respective pass through bore hole oriented in a longitudinal direction of the extruder screw, wherein the screw segments are slid onto the tension rod with the pass through bore hole and axially supported at a tip of the tension rod; a counter element that clamps the screw segments against the tip of the tension rod at an end of the tension rod wherein the end is arranged distal from the tip; and a locking element that is clamped between the screw segments and the counter element.

Methods, apparatuses, systems, and techniques relate to a tube-forming device for an extruder unit or an extrusion device and a tube-forming process. The tube-forming device comprises at least one shaping sleeve, which is designed to shape a supplied stream of polymer melt from a substantially strand-like cross section into a tubular cross section. The shaping sleeve has a guiding passage embedded in the sleeve wall, such that the guiding passage is a cavity which lies within the sleeve wall and, in the radial direction of the shaping sleeve, is enclosed in a sealed manner with respect to the outer surfaces.