The tension control system of aluminum foil is a special follower system in which the input quantity varies according to some adjustable attenuation law. In the process of overprinting of gravure aluminum foil, tension adjustment and change directly affect the accuracy of overprinting and printing, printing process control is one of the key factors. Tension control is the core of machine control. As long as the tension control is stable, the tension change is small, the aluminum foil in the overprint accuracy and the rejection rate is very easy to control. However, in the aluminum foil printing process, the tension fluctuations and changes in factors are multifaceted, need to be carefully analyzed.
First, the diameter of the rewinding rolls is constantly changing due to the roll of the press during the winding and unwinding process. Unloading in the case of constant braking torque, the diameter decreases, the tension increases, the rewinding is the opposite, if the winding torque does not change, with the winding diameter increases, the tension will be reduced. This is the inherent characteristics of the press determined, but also caused by aluminum foil tension changes in the main factors.
Second, the uneven quality of aluminum foil material, affecting the tension changes, such as the elastic modulus of the material fluctuations, the thickness of the material along the width of the length of change, the volume of eccentricity, and the level of heating will give the machine Tension brings subtle effects.
Third, the press in the refueling or material breakage process will make the machine has been stable tension suddenly produce interference changes. Equipment, the higher the speed, the greater the interference, tension changes, poor stability. Should be quickly according to the tape tension interference automatically adjusted to make the tension in time to restore the original steady state. In the overprint on the printing of the coil in the transmission should have a moderate tension, tension is too small, the test at the Department of the membrane prone to jitter, affect the accuracy of overprint, the tension should be constant to ensure that the instantaneous linear speed constant, and requires the main motor running To be smooth, can not be fast when slow, can not tremble, otherwise affect the accuracy of overprint.