Degassing device on a worm extruder

摘要

A degassing device on a worm extruder having a worm housing accomodating the worm or worms and provided with at least one degassing passage opening into the worm chamber of the housing is provided with a return delivery device for material which has penetrated from the worm chamber into the degassing passage. The free surface (evaporation area) of the extruder material within the degassing passage amounts to more than about 40% of the degassing passage cross-section, and the smallest gas passage cross-section of the return delivery device amounts to at least about 0.1 times, the degassing passage cross-section. Especially in the case of pasty material this reliably prevents a blockage of the degassing passage by the material processed in the worm extruder.