Answers to questions in the production of six-high reversing mills, cold rolling technology

1. Как управлять усилием прокатки?

The rolling force is large, the shape of the plate is difficult to control, the temperature of the roll is uneven, and the bearing capacity of the roll is reduced. Newly replaced work rolls generally use a large tension to reduce the rolling force, which can be reduced after rolling 2-3 rolls.

Relatively speaking, the rolling force is too small and the thickness is difficult to control. The resistance of the tension roll can be reduced and the rolling force can be increased relatively.

2. Как контролировать колебания толщины?

Large thickness fluctuations occur in the rolling process. First, reduce the speed and reduce the tension difference. If the thickness fluctuations are large, the monitoring can be canceled.

For thickness fluctuations within 20ym, the speed should be below 500 meters, and the fluctuations above 20ym and the speed below 300 meters.

3. Чем вызвано появление трещины на кромке?

1. The roughness of the edge of the roll is low.

2. There is a color difference on the edge of the strip.

3. The total deformation is too high, and the final pass reduction is too large, which may cause edge cracks after rolling.

4. The raw materials are bulging and cracking.

5. Pickling and trimming are not good.

4. How to control the cracked edge and the broken belt?

When the cracked edge is serious, reduce the bending force of the work roll, reduce the rolling speed, and reduce the exit tension. The tension on the edge of the strip is reduced, and the cracked edge will not be pulled off. If it is found that the edge of the strip is bulging, replace the work roll in time.

5. During the rolling process, what is the reason for the deviation of the belt outline? How to deal with it?

During the rolling process, the deviation of the strip generally occurs when the strip is worn or the tail is flicked. The main reasons for the deviation of the strip are as follows:

1. Due to the incoming material, the shape of the incoming material is not good, and there are serious side waves or wrong sides, so that the centering device of the uncoiler cannot be adjusted accurately and timely, resulting in the deviation of the strip in the first pass. The measures to be taken are: The rolling speed should not be too high, adjust the position of the reduction side in time or stop in time.

2. Operation reasons Due to the unreasonable adjustment of the swing by the operation pressure, the strip steel runs off.

3. Electrical reasons Due to the sudden reduction or disappearance of the coiler tension during the rolling process, the strip runs off and the strip is broken.

4. Due to the serious taper of the roll after grinding, it is difficult to find the pressing, which increases the difficulty of operating the pressing and swinging during the rolling. Broken belt.

5. The failure of the unwinding centering device, the pollution of the lamp tube or the receiving device, etc., make the deviation device fail and cause the first deviation.