Abstract: A method of manufacturing extruded pipes where plasticized material, for example plastic material, is advanced to an extrusion nozzle comprising a circular gap (2). The method is especially characterized in that the material is transported axially in said gap (2) while material is moved, for example rotated, in the circumferential direction of the gap (2) so that the material at least partially is caused to assume an orientation deviating from the axial direction, whereby a non-axial orientation will prevail in the extruded pipe (3) and increase the strength. The invention also relates to an apparatus for carrying out the method.
Type:
Grant
Filed:
December 11, 1984
Date of Patent:
August 11, 1987
Assignee:
Mats Lundberg
Inventors:
Andre Dziewanowski, Krzysztof Piotrowski, Krzysztof Zaremba