Continuous hot dip galvanizing production line

How is the front and back tension of the machine controlled?

With the development of hot dip galvanizing production line technology and the improvement of surface quality requirements of galvanized sheet by users, the light machine has become more and more indispensable and important equipment, which plays a vital role in the product quality of galvanized production line. The tension control is very important in the practical application of the machine, which is the key to the stable operation of the machine.

In continuous hot dip galvanizing production line, the first condition is to ensure the stability of the tension at the entrance and exit of the machine. This is achieved by the tension control system. The inlet and outlet of the machine are equipped with tension measuring rollers to measure the actual tension, which are used as feedback signals to control the tension.

When the production line is arranged, the outlet side of the light machine is the tension leveller, and the tension roller between the light machine and the tension roller is the speed reference roller of the whole production line, which is constant speed and does not participate in the tension control. In this way, the tension of the light machine is generated by the tension roller of the population side pulling the galvanized sheet backward. The tension difference between the outlet side and the inlet side of the machine is also the result of the working roller pulling the galvanized sheet backward during operation, so that the outlet side tension is slightly larger than the inlet side, so that the outlet side tension can be controlled stably.

According to the characteristics of tension leveller, polisher and process section, the tension decreases gradually according to the sequence of exit of polisher, entrance of polisher and process section. That is to say, in addition to the positive torque output by the tension roller at the outlet of the tension leveller, the tension roller at the entrance of the tension leveller, the working roller of the smooth machine, the tension roller at the entrance of the smooth machine, and the heat tensioning roller are all negative torque output.

The tension at the outlet of the machine is controlled stably by the working roller of the machine, while the tension at the inlet is controlled stably by the tension roller of the inlet. As shown in the figure,

Integrated control system diagram of the finishing machine

When after the export side set tension to tension controller, the system will export side yi cheung measurement to the actual tension signal feedback to the export side of regulator, after comparison operation signal to the speed regulator, by adjusting the speed of light overall work roll to ensure the stability of the tension: the actual tension, the work roll turn faster, export a lighter side galvanized sheet, tension is decreased; Otherwise, the work roll will turn more slowly, which will increase the tension. Similarly, when the inlet tension is set to the tension controller, the system feeds back the actual tension signal measured by the inlet tension meter to the tension regulator, and sends the signal after comparison operation to the speed regulator, which ensures the stability of the inlet tension by adjusting the rotation speed of the inlet tension roller.

It should be noted that the speed of the inlet tension roller and the work roller is the same as that of the outlet tension roller, subject to the unified control of the production line speed setting, that is, it varies with the change of the production line speed. Tension control is only a fine-tuning on this basis.