DEVICE FOR APPLYING A PROFILING IN AN EXTRUDED PRODUCT AND METHOD FOR APPLYING THIS PROFILE.

摘要

A device for producing a profiling in an extruded product comprises an outer mould and a mandrel which together execute a back and forth movement in the extrusion direction. Expendable sealing means made of elastic material are accommodated in grooves on the circumference of the mandrel and are arranged with a mutual spacing in the extrusion direction in order to seal off the part of the inner wall of the extruded product between the seals. The space between this part of the inner wall of the extruded product and the mandrel can be connected to a pressure source to generate the profiling. The sealing means can be moved in the grooves, however still sealing with the wall of the grooves. The space between the sealing means and the base of the groove can be alternately connected to a pressure source or to a vacuum source for expanding or retracting the sealing means. During the production of the profiling in the extruded product, the sealing means are expanded when the outer mould and the mandrel move in the extrusion direction and are retracted during the return movement of the mould and of the mandrel.