Factors affecting the tension of the slitter

1) Changes in speed will cause changes in the tension acting on the coil. Taking the film slitting machine as an example, when the speed increases for a short time at the beginning, more air will be brought between the film layers, making the film roll up very soft. At this time, the tension should be increased to seal the gap between the layers. air out. When the speed of the slitting machine climbs to the set value, the pressure at this time will tend to be stable if the speed is constant. When the slitter decelerates to the stage of stopping, the tension value at this time will decrease with the decrease of speed.
2) During the winding and unwinding process of the slitting machine, the tension changes with the change of the material diameter. During the unwinding process, the coil diameter gradually decreases, and the tension increases continuously under the condition of constant torsional torque. Rewinding is just the opposite. As the diameter of the roll increases, the unwinding tension decreases at the same moment, resulting in the finished roll becoming soft or even off-track. This requires the slitter tension control system to pre-set the taper tension attenuation and compensation value to maintain a constant tension.
3) The structural design of the slitting equipment and the precision of the parts will also affect the tension. The transmission roller includes the transition roller, the precision problem of the floating roller or the flattening roller will cause the tension imbalance, and the inconsistent air pressure on both sides of the pressure roller will cause the two ends of the film roll to loosen and tighten at the same time. The friction coefficient between the drive pulley and the belt will affect the tension, which can be compensated by calculating the resistance. The larger the wrap angle of the roller, the greater the tension difference between the elastic and tight sides of the roller. When the roller is a driving roller, the tension of the material entering the roller is relatively high, and the tension of the material leaving the roller is relatively small. When the roller is a passive roller, because the roller is driven by tension, the tension of the material is relatively high when it leaves the roller.
4) In addition to the process, the characteristics of the material itself will also affect the cutting tension. For example, material width, thickness tolerance, inconsistent elasticity, the influence of environmental temperature and humidity on materials, etc. The tension fluctuation caused by this aspect is relatively difficult to control, and it is necessary to explore the law in practice. Lipu slitter will determine different slitting parameter curves for different material properties, so as to achieve constant tension control.