Abstract: The invention describes a device (1) that is intended for longitudinally stretching film webs (2) and that comprises a plurality of rollers (5, 6, 9, 10, 11, 12, 13, 18, 19), some of which are temperature control rollers, and some of which (9-13) form stretching gaps (22), in which the film web (2) can be stretched. At least one of the rollers (5, 6, 9, 10, 11, 12, 13, 18, 19) has a drive that is torque controlled.

Abstract: A process for the automatic control of the thickness of extruded film lowers the deviations in the thickness of the film more quickly after the start of the extrusion process. The process includes the measurement of the thickness profile of the film just extruded by means of a thickness-measuring probe. The thickness-measuring probe is moved along the surface of the film substantially perpendicular to the conveying direction of the extruded film. The thickness-measuring probe records a thickness profile of the film for each measuring cycle at least over parts of the expansion of the film perpendicular to its conveying direction. While providing statistical values in relation to older measured values, the latest measured values during a predetermined time-frame at the start of the extrusion process are more heavily weighted by a computer than those measured during the normal operation.

Abstract: The present invention relates to a process for the automatic control of the thickness of extruded film (8). The purpose of the invention is to lower the deviations in the thickness of the film more quickly after the start of the extrusion process. The process involves the measurement of the thickness profile of the film just extruded (8) by means of a thickness-measuring probe (12). The thickness-measuring probe (12) is moved along the surface of the film substantially perpendicular (x) to the conveying direction (z) of the extruded film (8). The thickness-measuring probe (12) records for each measuring cycle (MZ) a thickness profile (P) of the film (8) at least over parts of the expansion of the film (8) perpendicular (x) to its conveying direction (z).

Abstract: The present invention relates to a process for the automatic control of the thickness of extruded film (8). The purpose of the invention is to lower the deviations in the thickness of the film more quickly after the start of the extrusion process. The process involves the measurement of the thickness profile of the film (8) just extruded by means of a thickness-measuring probe (12). The thickness-measuring probe (12) is moved along the surface of the film substantially perpendicular (x) to the conveying direction (z) of the extruded film (8). The thickness-measuring probe (12) records a thickness profile (P) of the film (8) for each measuring cycle (MZ) at least over parts of the expansion of the film (8) perpendicular (x) to its conveying direction (z).