Longitudinal stretching mechanism and method for replacing worn structural unit

Abstract

The invention relates to an improved longitudinal stretching device, which is characterized by the following features: in addition to a mounting or operating position (A) for a structural unit (21) to be replaced, the longitudinal stretching device further comprises a preparation position (D) and / or a preparation station (19), in which a further structural unit (21) is prepared; the preparation position (D) and / or the preparation station (19) are / is arranged and / or designed with respect to the longitudinal stretching mechanism. According to the invention, the further component unit (21) prepared at the preparation position (D) and / or the preparation station (19) has reached or can reach an operating temperature or at least reaches a preheating temperature which is higher than the operating temperature or less than 30 DEG C lower than the operating temperature before being installed in the operating position (A). By means of the solution according to the invention, a simple and in particular less complicated replacement of the component to be replaced and in particular the roller can be achieved.

Description

technical field [0001] The invention relates to a longitudinal tensioning mechanism according to the preamble of claim 1 and to a method for replacing a structural unit that is subject to wear in a longitudinal tensioning mechanism. Background technique [0002] In the longitudinal stretching of the plastic film, the film web is stretched longitudinally between successive rollers, wherein the downstream roller rotates at a higher rotational speed or circumferential speed, respectively, than the preceding roller. The film is thus stretched longitudinally in the gap between these two successive rollers. [0003] In order to ensure that the film rests more neatly on the corresponding treatment roller or deflection roller, the above-mentioned pressure rollers or nip rollers are used in order to press the moving material web, especially the plastic film film to be stretched, against the entire surface onto the circumference of the turning or handling rolls. [0004] The film is...

AI Technical Summary

Problems solved by technology

[0011] - The disassembly of the member / roller to be replaced is very labor intensive and time consuming;

[0012] - the components to be replaced and the existing ones for the pneumatic mechanism, for the heating device, in particular in the form of a hot water pipe through which hot water up to 130° C. is conducted, and for the electrical connection lines The separation of joints is also expensive and time-consuming;

[0013] - But reconnecting the above-mentioned components during installation is also a complex construction, especially connecting the hot water pipes and connecting the pneumatic and electrical lines, and the hot water pipes must be filled and vented again (in order to make the hot water pipes release air trapped during assembly);

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