Process for producing extruded plastic products, in particular plastic pipes

摘要

In plastics processing, in particular in film production, large amounts of nonreclaimable plastic residues or film residues occur. It has hitherto not been possible to reprocess these in an efficient way. The invention now proposes a process which makes possible a reprocessing of such (film) plastic residues. In the process according to the invention, a mixture of extremely finely ground plastics material (regrind) is fed to an extruder. By virtue of the extremely fine grinding and the subsequent mixing of the regrind from different batches, a free-flowing regrind with a specific bulk density is obtained, which can be processed virtually as (virgin) granules. The process according to the invention is suitable in particular for reprocessing rigid polyvinylchloride residues, such as occur in film production. Plastic pipes can be especially readily produced from the regrind produced therefrom.