The invention relates to a pin-barrel extruder comprising a barrel and a screw which is mounted rotatably in said barrel and has a thread which transports the extrudate and into which grooves are cut in radial planes, into which grooves pins which are attached in or on the barrel and project radially into the barrel engage. The object of the invention is to provide a simple possibility of breaking down and plasticating coarse material components over a short distance without impairing the output capacity and thus of obtaining outstandingly homogenised extrudates over a short distance. The invention consists in that, in a pin-barrel extruder of the type mentioned at the outset, a further thread with a higher number of flights and a greater pitch, but a lower flight depth and preferably also lower flight width is cut into the screw thread on both sides of at least one pin plane. This combination achieves a high increase in the plastication effect without the output capacity being reduced. The extruder can thus be shorter in construction and even be dimensioned smaller overall. Despite this, the homogenisation is outstandingly good. IMAGE IMAGE
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