The purpose of protective film slitting and common problems of winding
Why should the protective film be slit? Today, I will discuss with you the purpose of protective film slitting and the common problems of protective film slitting and rewinding. We know that the purpose of protective film slitting is generally four: ①According to user requirements, provide accurate specifications; ②When slitting and unwinding, the entire upper process can be extruded and compounded when compounding large rolls of composite film Re-inspect to see if there is any quality problem; ③The faulty layer of the composite film can be corrected or part of the printing and composite defects can be cut off, and the grade rate of the product can be improved; ④The finished product can be in a good winding state.1. What should I do if the end face of the slit film roll is poorly neat? There are probably three reasons for this problem.
Reason 1: The photoelectric tracking is inaccurate during slitting.
1. The photoelectric eye adjustment method and working status are incorrectly selected, and should be re-adjusted according to the requirements of the operating procedures.
2. The chromatic aberration of the tracking line is not obvious, the chromatic aberration contrast should be increased.
Reason 2: The winding tension is small.
Solution: increase the winding tension, and if necessary, add an appropriate amount of new magnetic powder to the magnetic powder clutch.
Reason three: The film generates static electricity accumulation, and adhesion or drift occurs between the films.
Solution: Connect a static conductive device to the slitting device, and contact one of the antennae on the back of the film roll.
Second, how do the longitudinal stripes on the surface of the film roll occur?
Longitudinal stripes refer to the circular linear stripes formed on the surface of the film roll. The reasons for this phenomenon:
1. A large amount of air entrapment and poor cumulative thickness tolerance during the slitting/rewinding process are the main reasons for longitudinal streaks. Once more serious streaks appear It is difficult to eliminate. One of the reasons is that the cutting speed is too fast. Generally speaking, the quality problems of longitudinal streaks and staggered layers are most likely to occur at high speeds.
2. The operating accuracy of the equipment. For equipment that requires high operating accuracy, after a long period of continuous use, the operating accuracy of some parts has been reduced. For a large slitting machine, it is more difficult to ensure the accuracy of the operation due to the large operating parts. And because the plastic film is a polymer product, its thickness is very thin, and it is more susceptible to damage during processing, so once the operation accuracy is not enough, it is easy to produce quality problems such as longitudinal stripes. So far, you should be cautious when replacing equipment parts and accessories. It is advisable to choose durable and high-precision parts, and you must ensure a certain accuracy during installation, otherwise it will be difficult to meet the operating needs of the slitting machine.3. Why does the bottom wrinkle occur? The bottom wrinkle only occurs in a certain length of the film at the beginning of rewinding. It is manifested by many and deep wrinkles and streaks, which are caused by many factors. For example, in terms of process parameters, different types of slitting machines have different setting methods, methods, and values u200bu200bof process parameters. The performance of the equipment itself and the intrinsic properties of the film do have a great impact on the quality of film slitting and winding, but a suitable process can improve quality problems such as longitudinal stripes and bottom wrinkles. Different equipment and different types of films should adopt appropriate slitting processes. When equipment conditions change, process adjustments can also be used to compensate, but process adjustments must be cautious.