A change in speed causes a change in the tension on the web. Taking thin film slitting machine products as an example, when the speed increases for a short time at the beginning, more air will be brought in between the film layers, making the film roll up softly. At this time, the tension should be increased to seal the gap between the layers. air out. When the speed of slitting machine products climbs to the set value, the pressure at this time will tend to be stable if the speed is constant. When the slitting machine products decelerate to the stop stage, the tension value at this time will decrease with the decrease of speed.

During the winding and unwinding process of slitting machine products, 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 slitting machine products tension control system to pre-set the taper tension attenuation and compensation value to maintain a constant tension.