Abstract: The invention relates to a method for saving energy in an extrusion line comprising at least one extruder, an extrusion tool, a cooling section, and an outlet, energy being applied in the form of heat to a plastic for plasticization at least in the extruder, in order to produce a profile (8), and the heat being removed again from the profile (8) after a forming process, at least in the cooling section, in order to achieve shape stability of the same. According to the invention, at least one part of the removed heat is converted to mechanical energy and fed hack into the extrusion process. The invention further relates to a corresponding device.

Abstract: An extruder for processing of thermoplastics has a housing (1) in which a screw is pivotally supported. A land (5) which runs in a helical line protrudes from the core (4) of the screw. There is at least one ventilation opening in the housing in which the screw is pivotally supported. The land (5) of the screw at least in the area of the ventilation opening has an active flank, i.e. one which points toward the discharge end of the extruder and which encloses with the axis of the screw an acute angle such that at least in areas it is set back relative to a radial plane which passes through the outside edge (14) of the active flank (10). This prevents the plastic which is to be processed in the extruder from being pressed to the outside and clogging the ventilation opening.

Abstract: An extruder for processing of thermoplastics has a housing (1) in which a screw is pivotally supported. A land (5) which runs in a helical line protrudes from the core (4) of the screw. There is at least one ventilation opening in the housing in which the screw is pivotally supported. The land (5) of the screw at least in the area of the ventilation opening has an active flank, i.e. one which points toward the discharge end of the extruder and which encloses with the axis of the screw an acute angle such that at least in areas it is set back relative to a radial plane which passes through the outside edge (14) of the active flank (10). This prevents the plastic which is to be processed in the extruder from being pressed to the outside and clogging the ventilation opening.