JPS6026606B2 - Roll eccentricity control method for rolling mill - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a roll eccentricity control method for a rolling mill using a roll eccentricity waveform memory method.

The roll eccentricity control of the rolling mill uses a roll eccentricity waveform memory method.
There are Fourier series method and correlation function method.

All of these are preliminary control systems that create a disturbance compensation amount by adding a function to the backup roll rotation angle and the amount of roll eccentricity. Therefore, in order to improve the accuracy of predictive control, it is necessary to predict the disturbance correctly and to create the correct amount of disturbance compensation by taking into account delays in the control system. As a control method devised for this purpose, there is a conventional method in which the amount of roll eccentricity of the backup roll is taken out and stored in advance during non-rolling, and then read out during rolling to compensate. FIG. 1 shows an overview of a conventional roll eccentricity control method.

In Fig. 1, 1 is a work roll, 2 is a backup roll (hereinafter, the upper backup roll is referred to as the upper roll 2a,
The lower backup roll is referred to as lower roll 2b), 3
numeral 4 indicates a material to be rolled, and 4 a load cell for detecting rolling force. 5
, 6 indicates a pulse generator that detects the rotation angle of the backup roll.

7 is a cylinder for reduction, and this has a displacement detection end 8 on the movable part.
is attached.

The output of this displacement detection end 8 is
The signal is then fed back to the Schilling 7, forming a position control system. Further, the output of the load cell 4 passes through a lock-on device 14, an arithmetic unit 12, and a converter 13, and enters an arithmetic unit 9, forming a so-called BISRA type control system. Further, the output of the load cell 4 passes through a lock-on device 14, enters a sampler 15, an A/D (analog-digital) converter 16, and enters a digital computer 17. The pulse generators 5 and 6 generate resolution pulses (one pulse corresponds to resolution) and one-rotation pulses 31, and the resolution pulses 30 from the pulse generator 5 are counted by the counter 18 and simultaneously counted by the sampler 15. The timing is determined and the timing for the digital computer 17 to read the output of the A/D converter 16 is provided. counter 8,
26, 21, and 25 count the pulses from the pulse generators 5 and 6, respectively, and receive glue set signals 32, 33, 34, and 35 from the digital computer 17, respectively.
will be reset. Counters 8 and 21 serve as counters that detect the rotation angles of upper roll 2a and lower roll 2b, respectively. Further, the counters 26 and 25 are respectively set to the upper roll 2.
It counts one rotation pulse from a and one rotation pulse from the lower roll 2b, and by counting the upper and lower rolls continuously from several to several tens of rotations, it detects the difference in rotation between the upper and lower rolls 2a and 2b. used for. The counter 20 counts pulses from the pulse oscillator 19, and at the same time is set and reset by the one-rotation pulse 31 from the pulse generator 5 to detect the time for one rotation of the upper roll 2a. The output of this counter 20 is input to the digital computer 17, which calculates the rotational frequency and is used to compensate for delays in the control system. 22 is a D/A (digital-to-analog) converter that converts the roll eccentricity compensation amount created by the digital computer 17 into an analog amount and inputs it to the arithmetic unit 12.

A switch 23 is interposed between the D/A converter 22 and the arithmetic unit 12. This switch 23 turns on/off the roll eccentricity control, and is operated from the console 24. Further, from this console 24, a digital computer 17 is connected.
You can also send a signal to

The operation of the follower method configured in this way is divided into two stages: one is to bring the upper and lower work rolls into contact with each other without the material 3 to be rolled, apply a predetermined load, and roll at a predetermined number of rotations. This is a process in which the eccentric waveforms of the upper and lower rolls 2a and 2b are separated and stored in the digital computer 17 while rotating the rolls. The other step is to perform roll bias D control using the stored waveform. This method has the advantage that the roll eccentricity waveform is separated in advance and predictive compensation control is performed using that waveform, allowing sufficiently stable control even when there is a plate thickness disturbance. However, the roll eccentricity waveform has the characteristic that its amplitude changes depending on the rolling force, and the rolling force when the waveform is separated and stored does not match the rolling force during actual rolling, so it is not possible to compensate only with the memorized waveform itself. Unable to obtain satisfactory control results.

The roll eccentricity waveform also changes in amplitude in response to various changes in the rolling force, but conventional methods always control with a fixed waveform stored in advance, which does not correspond to the characteristics of the actual roll eccentricity waveform. There was a 0 point.

The present invention has been made to eliminate such drawbacks in the conventional method, and in roll eccentricity control of a rolling mill, a roll eccentricity signal component during non-rolling is extracted for each backup roll arranged oppositely, and Store each extracted eccentric signal component in the computer,
The stored contents are read out in synchronization with the respective backup roll eccentricity signals during rolling, they are combined and output as a roll eccentricity control signal, and the output signal is multiplied by a function determined from the rolling force. The object of the present invention is to provide a method for controlling roll eccentricity of a rolling mill that can perform stable and effective roll eccentricity control, by using the resulting signal as an operation signal for control.

An embodiment of the present invention will be described below.

In FIG. 2, the amount of roll eccentricity compensation created by the digital computer 17 is passed through the D/A converter 22 to the function multiplier 2.
7 and is input to the arithmetic unit 12.

The function multiplier 27 performs a correction operation on the signal from the D/A converter and the signal 36 given from the load cell 4 through the converter 38 to create a correct amount of eccentricity compensation. FIG. 4 illustrates a specific example of this new control method. This diagram illustrates the function between the maximum amplitude of the roll eccentricity waveform and the rolling force. Here, if the first roll eccentricity waveform memory (no material to be rolled) is performed with a rolling force of 100 moN, the maximum amplitude of the roll eccentricity waveform at that time is 50 mm from Fig. 4, so the function multiplication The function shown in Figure 5 can be found as a function to be given to the vessel. The function multiplier 27 receives the pushing force signal 36 from the load cell 4 through the converter 38 and calculates a correct correction value. For example, in FIG. 5, when the rolling force is 50 degrees oN, the compensation value stored in the digital computer 17 is multiplied by a ratio of 0.94 to determine the correct compensation value. Here, the compensation value is corrected only with respect to the amplitude, and the control signal is output by correctly advancing the phase in consideration of the delay in the control system, which is similar to the subordinate method. Further, the function multiplier described above can be replaced with software calculation in the digital computer 17, and the function multiplier can be omitted as shown in FIG. In this case, it is necessary to provide a line that supplies the rolling force signal 17 directly to the digital computer 17.

In the roll eccentricity control system shown in FIG.
It is assumed that rolling is performed using ron. At this time, the roll eccentricity waveform entrusted to the digital computer 17 in advance is the one with a rolling force of 100 plates on, so the maximum amplitude is 50 degrees, but the roll eccentricity waveform that actually appears The maximum amplitude of is 47〃, as determined from the relationship shown in FIG. Therefore, if the 50 peaks are used as the operation signal as a compensation value for roll eccentricity control, it will result in overcompensation, and correct compensation cannot be performed. However, if a reduction force of 500 Ton is applied to the function multiplier 27 from the load cell 4 through the converter 38, the function generator 27 will generate 50 m x 0.94 = 47 m based on the relationship shown in Figure 5. The corrected operation signal 47 is given to the calculator 12. Perform control to correctly cancel out the eccentricity of the roll. Furthermore, even if the shoring force to the higuchi changes due to operational needs, the function calculator 27 continues to perform the calculations described above in response to the change, and provides the correct compensation signal to perform effective roll eccentricity control. I can do it. That is, according to the present invention, in roll eccentricity control of a rolling mill, a roll eccentricity signal component during non-rolling is extracted for each backup roll arranged facing each other, and the extracted eccentricity signal component and each other are stored in a computer. This memory content is read out in synchronization with the rotation angle of each backup roll during rolling, combined and output as a roll eccentric control signal, and the output signal is multiplied by a correction value determined from the rolling force. , the gist is that control is performed using the resulting signal as an operation signal.

Therefore, even if there is a change in the amplitude of the roll eccentricity signal due to a change in the rolling force, it can be correctly compensated for, and a reduction in control performance due to overcompensation or undercompensation can be avoided, and extremely accurate roll control can be achieved. A method for controlling eccentricity can be provided.

[Brief explanation of drawings]

Figure 1 is a diagram showing the method of controlling the roll eccentricity of the follower, Figure 2 is
FIG. 3 is a diagram showing the configuration of an embodiment of the present invention, FIG. 4 is a diagram showing the relationship between the rolling force and the maximum amplitude of the roll eccentricity waveform,
Figure 5 is. FIG. 6 is a diagram showing the relationship between the rolling force and the correction ratio when storing the roll eccentricity waveform. 1...Work roll, 2...Backup roll, 4...Load cell, 5, 6...Pulse generator, 17...Digital computer. Rudder map

Claims (1)

[Claims] 1. In the roll eccentricity control of the rolling mill, the roll eccentricity signal component during non-rolling is extracted for each back-up roll arranged facing each other, each extracted eccentricity signal component is stored in a computer, and the stored contents are is read out in synchronization with the rotation angle of each back-up roll during rolling, they are combined and output as a roll eccentric control signal, and the output signal is multiplied by a function determined from the rolling force. A method for controlling eccentricity of a rolling mill roll, characterized in that control is performed by using a signal generated by the input signal as an operation signal.