Магистерская диссертация тема работы Разработка цифрового двойника технологического процесса с использованием производственных данных

1.6.4 Nip rolls 
Tension isolation between TDO and winder is provided by nip rolls on the 
treater stations. It is important to have a controlled tension between TDO and inside 
treater, between inside and outside treater, between outside treater and pull rolls and 
pull rolls to winder otherwise the winder will pull the film through the trim removal 
section and cut the web on blades. 
Attached to every corona treatment roll there is a nip roll to prevent slipping of 
the film on the rolls. Thus, the winder cannot pull the film through the pull roll stand. 
Moreover, the proper nip roll operation is essential for the elimination of reverse 
treatment created by air between the film and the corona roll. 
1.6.5 Spreader rolls pair 
By pulling the edge of the film, the spreader roll pair removes completely the 
wrinkles during the transportation of the film. 
1.6.6 Heating and cooling unit for corona roll 

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During corona treatment, the film temperature increases. Therefore, it is 
necessary to cool the corona rolls down to avoid crystallization due to the film heating. 
1.6.7 Edges recycling 
The film in the clips and the film close to the clips is very thick and cannot be 
wound into the film. To prevent waste production the edge trim is cut to fluff by a 
grinder and is recycled to the main extruder. This is in a continuous process during 
production. 
1.6.8 Film thickness gauge 
The thickness gauge is installed at the pull roll stand and is used for measuring 
the thickness profile of the final film. 
The film thickness is measured during production in a non-tangent and 
continuous way through an X-ray scanner. 
The thickness gauge does not only measure and indicate the film profile, but it 
also adjusts the film profile automatically and, by calculating the average film 
thickness for each scan, it keeps the film thickness on a constant level during 
production. 
During production, there are changes in the film profile. Therefore, the film 
tolerances must be corrected accordingly by readjusting the die lip. The coarse 
adjustment of the profile is made manually by push/pull bolts. The fine adjustment and 
control are taken over by the thickness gauge. For this purpose, the push/pull bolts are 
designed as heated expansion bolts. These expansion bolts are controlled by the 
thickness gauge. The necessary temperature of the expansion bolts is calculated by the 
computer of the thickness gauge concerning the measured film profiles.