JPS63203210A - Device for eliminating roll eccentricity - Google Patents

Abstract

PURPOSE:To eliminate variations in rolled sheet thickness caused by eccentricity of upper and lower backup rolls by subordinately treating load values by a rolling load detection means to a rotation angle by a rotation angle detection means and separately calculating an eccentrical amount of respective rolls. CONSTITUTION:Pulses generated by a pulse generator 18 directly connected to an upper backup roll 11 and a pulse generator 19 directly connected to a lower backup roll 12 are inputted to a roll eccentricity eliminator 20 and are converted into respective rotation angles of rolls 11, 12. A rolling load is also detected by a load cell 16 and is inputted to the eliminator 20. The eliminator 20 finds separately an eccentricity basic wave component and a higher harmonic wave component of the rolls 11 and 12 respectively by use of a high speed Fourier transformation method. Those components are synchronously regenerated with a rotation angle of the rolls 11, 12 and are outputted to a hydraulic draft controller 21, which controls a hydraulic device 17 to bring a rolled sheet thickness to be constant.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Field of Application) The present invention relates to a roll eccentricity removing device for removing variations in rolled sheet thickness due to eccentricity of an upper backup roll and a lower backup roll of a rolling mill. .

(Prior art) The method for measuring the eccentricity of the upper backup roll and back-up roll of a rolling machine involves a waveform memory that reads fluctuations in rolling load corresponding to the rotation angle of the rolls, converts them into eccentricity, and stores them. There is a fast Fourier transform method in which the eccentricity converted in the same manner is fast Fourier transformed and stored as fundamental wave and harmonic components.

In these methods, the rolls are brought into contact with each other (kiss roll) and rotated under a load during off-line, and the eccentricity of the rolls is measured for each of the upper backup roll and the lower backup roll based on fluctuations in rolling load.

However, this measurement during kiss rolling cannot eliminate the effects of deformation of the rolls caused by the rolling mill actually rolling the material, expansion due to heat, and the like.

Therefore, during rolling, the eccentricity of the upper backup roll and lower backup roll was measured all at once without separating them, and the weighted average of the values measured during kiss rolling was taken and used to control roll eccentricity removal.

(Problems to be Solved by the Invention) As described above, in the conventional roll eccentricity removing device, the amount of roll eccentricity measured by separating the upper backup roll and lower backup roll components during kiss rolling and the roll eccentricity measured at the same time without separating them during rolling Since the weighted average of the roll eccentricity measured by
This diameter difference is reflected in measurements during kiss rolling, but this is not reflected during rolling, making it impossible to accurately measure the amount of roll eccentricity, making it impossible to eliminate roll eccentricity.

Furthermore, off-line kiss rolling, applying a load to the rolls, rotating the rolls, and measuring the eccentricity of the rolls is actually not done very often, and is only done when the rolls are rearranged.

For this reason, it is not possible to cope with changes in the amount of roll eccentricity caused by deformation of the roll over time or wear, and it also has the disadvantage that roll eccentricity cannot be corrected.

The present invention has been made in view of these points, and includes the effects of expansion due to deformation and preheating of rolls during rolling.

Prevent roll deformation and wear over time without kiss rolling! E
+ Correspondingly, it is an object of the present invention to provide a roll eccentricity removing device capable of measuring the amount of roll eccentricity and removing roll eccentricity.

[Structure of the invention]

(Means for Solving the Problems) The present invention is realized by a configuration as shown in FIG. Here, the explanation will be based on a rolling mill comprised of work rolls 13.14 and backup rolls 11.12.

Pulses generated by the pulse generator 18 directly connected to the upper backup roll 11 and the pulse generator 19 directly connected to the lower backup roll 12 are input to the roll eccentricity removing device 20 and converted into rotation angles of the respective backup rolls 11 and 12. Ru.

Further, the rolling load during rolling is also detected by the load cell 16 and input to the roll eccentricity removing device 20. The roll eccentricity removing device 20 uses a fast Fourier transform method to separate the eccentric fundamental wave components and harmonic components of the upper backup roll 11 and the eccentric fundamental wave components and harmonic components of the lower backup roll 12 by a method described later. They are separated, regenerated in synchronization with the rotation angles of the respective backup rolls 11 and 12, and output to the hydraulic pressure reduction control device 21. The hydraulic pressure control device 21 uses this to control the hydraulic device 17 so that the gap between the rolls is constant, thereby making the thickness of the rolled plate constant. Note that 15 indicates a rolled material. The rolled material 15 moves in the direction of arrow 22.

(Function) Upper backup roll 11 and lower backup roll 12
A method for separating and measuring the eccentricity of
5911N, so it will be briefly explained here.

The pulse generators 18 and 19 used in the present invention emit two types of pulses: one mark pulse MP at the reference position during one rotation of the backup roll 11 and 12, and n pulses (hereinafter referred to as sampling pulses SP) during one rotation. .

The roll eccentricity removing device 20 according to the present invention is arranged so that the lower backup roll 1
According to the sampling pulse SP generated by the pulse generator 19 of No. 2, the rolling load ΔS0□ is sent from the load cell 16.
In addition to measuring and storing L (i is the number of samplings), the pulse generator 19 of the lower backup roll 12
The load cell 16 measures and stores the load Δ5ztj (j is the sampling number) in accordance with the sampling pulse generated by the pulse generator 18 of the backup roll 11 above the timing at which the mark pulse MP is generated.

Next, after shifting the rotation angle difference between the upper backup roll 11 and the lower backup roll 12 by a certain position (if there is a diameter difference between the upper backup roll 11 and the lower backup roll I2, they will naturally shift during rotation), the upper backup roll 11
The rolling load ΔS1□l is measured and stored from the load cell 16 in accordance with the sampling pulse SP generated by the pulse generator 19 of the lower backup roll 12 from the timing when the mark pulse MP is generated from the pulse generator 18 of the lower backup roll 12, and the pulse of the lower backup roll 12 is From the timing when the mark pulse MP is generated from the generator 19, the rolling load Δ5zzj is measured and stored from the load cell 16 in accordance with the sampling pulse SP generated by the pulse generator 18 of the upper backup roll 11. The difference δil = ΔSx, l-5t21 δzj = ΔS*IJ S2*J for each sampling pulse of these stored data is calculated, and δ□□ and δ2j are fast Fourier transformed, respectively, to create the upper backup roll 11 and the lower backup roll. The amplitude and phase of roll eccentricity of each roll 12 are detected separately. - [Example] An example of the present invention will be described below.

(Configuration of Embodiment) FIG. 2 shows a configuration diagram of an embodiment of the roll eccentricity removing device 2o according to the present invention.

The central processing bag @30 performs sampling of the rolling load and high-speed Fourier transform, and is composed of a microprocessor and the like. The storage device 31 is used to store programs, sampling data, etc. for controlling the present roll eccentricity removing device [20].

Pulse input device! 32 is the pulse generator 18.19
is connected to input each mark pulse and sampling pulse. Each input sampling pulse is counted by a built-in counter (not shown), and the counter is reset by each mark pulse. It also generates an interrupt signal 36 to the central processing unit 30 at every sampling interval. By reading the count values of each counter, the central processing unit 30
The rotation angle of each backup roll 11, 12 can be known. Analog input device 33 is load cell 1
Input the rolling load from 6. The analog output device 34 outputs a signal to the hydraulic pressure control device 121 for removing roll eccentricity.

These central processing unit 30, storage device 31, pulse input device 32, analog input table [33, and analog output device? ! 34 are connected by an internal path 35.

Note that the input/output of operation signals to the roll eccentricity removing device 20, signals indicating the status of the rolling line, etc. are not directly related to the present invention and are therefore omitted.

(Operation of Example) First, the central processing unit 30 separately measures the eccentricity of the upper backup roll 11 and the lower backup roll 12 using the method described in (Operation). Here, since the input from the analog input device 34 is the rolling load, it is necessary to convert it into the gap value between the rolls using the Mill constant and the plasticity coefficient. Regarding the amount, the fundamental wave component and harmonic component are determined based on one revolution of each backup roll 11, 12. Since these fundamental wave components and harmonic components each consist of a real part and an imaginary part, they are converted into the amplitude and phase of a sine wave. These sine waves having amplitude and phase are synthesized from the fundamental wave to harmonics according to the rotation angle of each backup roll 11, 12, and outputted to the analog output bag @34.

(Effects of Example) In this example, the amount of eccentricity of the backup rolls 11.12 is separately measured not only during kiss rolling but also during rolling, thereby deforming the backup rolls 11.12 during rolling. It is possible to eliminate roll eccentricity in response to the effects of expansion due to heat and heat, as well as the effects of deformation and wear over time of the backup rolls 11 and 12.

(Other Embodiments) In the configuration shown in FIG. 1, the roll eccentricity removing device 20 and the hydraulic lowering device 21 are separate devices, but they can also be combined into one device.

〔Effect of the invention〕

As described above, the amount of eccentricity of the upper backup roll and lower backup roll of the rolling machine was measured at least once during rolling using the roll eccentricity removing bag [20] using fast Fourier transform. By using it for control, it is possible to remove roll eccentricity by measuring the amount of roll eccentricity in response to the effects of roll deformation and expansion due to heat during rolling, as well as the effects of roll deformation and wear over time. .

As described above, the present invention is particularly effective in systems where measurement using kiss rolls is difficult, such as continuous casting lines and cold rolling lines.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of the present invention, and FIG. 2 is a diagram showing the configuration of the roll eccentricity removing device according to the present invention. 11... Upper backup roll 12... Lower backup roll 13... Upper work roll 14... Lower work roll 15... Material 16... Load cell 17... Hydraulic device 18... Pulse generator 19...Pulse generator 20...Roll eccentricity removing device 21...Hydraulic lower control device W 30...Central processing bag Pt31...Storage device 32...Pulse input device 33...Analog Input device 34...Analog output device 35...Internal bus 36...Interrupt signal agent Patent attorney Noriyuki Chika Ken Yudo Hirofumi Mitsumata Figure 1'' Figure 2

Claims (1)

[Scope of Claims] A roll eccentricity removing device that measures the eccentricity of an upper backup roll and a lower backup roll of a rolling mill using fast Fourier transform, and removes variations in rolled plate thickness due to these eccentricities, A rotation angle detection means inputs an angle signal from a rotation angle detection device provided on each roll to determine the rotation angle of each roll, a rolling load detection means inputs a rolling load, and a load value by this means is calculated from the rotation angle. 1. A roll eccentricity removing device comprising: arithmetic means that performs processing dependent on the rotation angle by the detection means and separately calculates the amount of eccentricity of each roll.