PLANT FOR PRODUCING A COEXTRUDED MULTI-LAYER FILM, APPARATUS FOR COEXTRUDING A MULTI-LAYERED COEXTRUSION COMPOSITE AND METHOD FOR COEXTRUDING AND ALSO METHOD FOR OPERATING A PLANT AND/OR APPARATUS FOR THIS PURPOSE

摘要

The invention relates to a plant for producing a coextruded multi-layer film (2), said plant comprising: at least one extruder device for providing material melts (33) of thermoplastic materials; an apparatus, comprising a coextrusion adapter (12, 13) and a nozzle part (33, 34), for coextruding a multi-layered coextrusion composite (3) of individual layers which are connected to one another, the coextrusion adapter (12, 13) comprising a central channel (40, 42) for producing a central layer (5) of the coextrusion composite (3), at least one coextrusion channel for producing at least one further layer of the coextrusion composite (3) interacting with the central layer (5), a plurality of displaceable setting elements (47) for setting layer thicknesses (50, 52) and/or layer thickness profiles in individual layers of the coextrusion composite (3), in addition to adjusting devices (53, 55) for actuating the setting elements (47); a drive unit (15, 17, 23) for driving the adjusting devices (53, 55); a measuring device (24, 25) for measuring layer thicknesses (50, 52) and/or layer thickness profiles in individual layers of the multi-layered coextrusion composite (3), the measuring device (24, 25) being designed to measure the individual layer thicknesses and/or the individual layer profiles downstream of the nozzle part (33); and a plant controller (17, 18) for controlling the plant, the plant controller (17, 18) comprising a controller unit (18, 19) which is designed such that relative positions of setting elements (47) can be manipulated automatically, preferably iteratively, by means of the drive unit (15, 17, 23) in accordance with layer thicknesses (50, 52) and/or layer thickness profiles measured in the multi-layer film already leaving the nozzle part (33, 34).