The problem of misalignment of hot-rolled coils in continuous casting and rolling mills is a long-term problem. The appearance of staggered layers brings inconvenience to the bundling, spraying and dispatching of steel coils, and at the same time makes the originally qualified strips become defective products after coiling, resulting in losses.
In practice, it is found that the reasons for the dislocation of hot-rolled coils are as follows:
1) The side guides are severely worn.
Since the strip steel passes through the side guide plate at a very fast speed, the working surface of the side guide plate is severely worn during the process of clamping the strip steel, so that the side guide plate cannot touch the strip steel at the set position when clamping the strip steel, resulting in a The steel moves between the guide plates on both sides, and the coiling is uneven. In this way, with the increase of the number of uneven turns, there will be staggered layers.
2) The cause of the side guide detection element.
After the position sensor is replaced, the position is not calibrated, so there is an error between the feedback position and the actual position, and then the guide plates on both sides will not be able to clamp the strip steel, so the force control cannot be activated, and the guide plates are always in the position control state when the strip steel passes, leading to misalignment; in addition, the feedback of the actual pressure value is wrong, which will also cause misalignment.
3) The problem of strip steel itself.
The side of the strip itself is uneven, if there is a sickle bend, or if there is a wave during the rolling process, the side guide plate will be subjected to a large force instantly, and the side with force control adjustment will open outwards for the protection of the equipment. , away from the strip to reduce the stress, at this time, the strip moves between the guide plates because it is not clamped, resulting in misalignment.
4) The cause of the pinch roller.
When the position deviation of the pinch rollers is too large on both sides during the coiling process of the strip or the pressure on the strip is too large, staggered layers will occur.
Measures to Solve the Problem of Hot-Rolled Coil Separation
1) Correct the position setting the value of the side guide.
When the side guide plate wears seriously, reduce the position setting the value of the side guide plate to allow the side guide plate to shrink inside to ensure that the strip is clamped; for the problem that the camber of the strip steel will cause excessive pressure on the side guide plate, set the position to Fixed value amplification.
2) Regularly replace the side guides and perform position calibration.
After the calibration is completed, it should be noted that the side guide plate should be manually opened and reversed to several positions, and the opening degree should be measured with a box ruler, and compared with the feedback value of the position sensor, in order to achieve compensation by increasing or decreasing the difference between the feedback value and the measured value In addition, the feedback values of the pressure sensors on the operation side and transmission side of the side guide plate should be carefully monitored, and attention should be paid to the recalibration and replacement of the sensor and the receiving module of the sensor.
3) Check the pinch roller regularly.
The pinch rollers are severely worn and should be replaced immediately. In addition, observe the feedback value of the pressure sensor on both sides of the pinch roller and compare it with the measurement value of the mechanical watch in the valve station. If the deviation is too large, it should be replaced in time.