JPS636288B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a plate thickness compensation control device for a multi-high rolling mill, and the present invention relates to a plate thickness compensation control device for a multi-high rolling mill. The purpose is to eliminate failures such as biting when biting.

FIG. 1 is a block diagram showing a conventional plate thickness compensation control device. The material to be rolled 1 is rolled by rolling rollers 2, 2a, 3, 3a,
The plate thickness is controlled to a predetermined value while advancing in the direction of arrow a through the space between 4 and 4a. 5, 6, 7 are electric motors for rotating the respective rolling rollers 2, 3, 4, 8, 9,
10 is a speed control device for each electric motor 5, 6, 7;
1, 12, 13 are respective rolling rollers 2, 2a, 3, 3
a, a lowering drive device for adjusting the interval between 4 and 4a, 1
4, 15, 16 are respective lowering drive devices 11, 12, 1
3, a rolling reduction amount control device 17 for the material to be rolled 1;
When the rolled material 1 is bitten by each of the rolling rollers 2, 2a, 3, 3a, 4, 4a (hereinafter referred to as "threading"), the material to be rolled 1 is bitten by each of the rolling rollers 2, 2a, 3, 3a,
When the rolling rollers 2, 2a, 3, 3a, and 4, 4a are detached from each other (hereinafter referred to as bottom removal)
18 is a rolling speed setting device that provides a reference value of the rolling speed to the speed controllers 8, 9, and 10; 19 is a rolling speed setting device for each rolling roller 2, 2a, 3, and 3a before the start of rolling; , 4. A rolling schedule calculation device that provides the rolling speed and rolling reduction amount of 4a to the rolling reduction amount compensating device 17 and rolling speed setting device 18, 2
0 indicates each rolling roller 2, 2a, 3, of the material 1 to be rolled.
This is a rolling state tracking device that detects the passing of sheets to 3a, 4 and 4a, and the end of the sheet.

Next, the operation will be explained. Before the start of rolling, the rolling schedule calculation device 19 gives the rolling amount and rolling speed of each rolling roller 2, 2a, 3, 3a, 4, 4a to the rolling amount compensating device 17 and rolling speed setting device 18. This is the steady state of rolling, that is, the rolled material 1 is rolled by all the rolling rollers 2, 2a, 3,
This is the rolling reduction amount and rolling speed when the rolling speed is set at the planned rolling speed. This is the steady setting value Sio・
Vio (I-th rolling mill rolling roller rolling reduction setting value Sio
and rolling speed setting value Vio).

Also, calculate in advance the amount of rolling so that the sheet thickness at the exit side of each rolling roller becomes a predetermined thickness in a state where the material 1 to be rolled passes through or falls through, and there is no front tension or rear tension of the i-th rolling roller. I'll keep it. This is referred to as Sib・Sif (the predicted rolling reduction amount in the absence of rear tension of the rolling roller of the i-th rolling mill).
Sib, the amount of reduction in the absence of forward tension.
Sif). The rolling reduction compensating device 17 stores these rolling reduction amounts Sio, Sib, and Sif transmitted from the rolling schedule calculation device 19.

The above-mentioned rolling reduction amount compensating device 17 is the rolling reduction amount control device 1
4, 15, 16 through the lowering drive device 11, 1
2.13, each rolling roller 2.2a, 3.
Set the rolling reduction amount Sif of 3a, 4 and 4a. At the same time, the rolling speed setting value Vio is given to the speed control devices 8, 9, and 10 through the rolling speed setting device 18, and the rolling roller rotation drive electric motors 5, 6, and 7 are set at a speed ratio according to the value of the rolling speed setting value Vio. It can be rotated with

In this state, the material 1 to be rolled is rolled by the rolling rollers 2 and 2a.
Then, when the rolling rollers 3 and 3a are bitten, this is detected by the rolling state tracking device 20. At this time, the reduction amount of the rolling rollers 2 and 2a is controlled through the reduction amount control device 14 so that it becomes the steady reduction setting value Sio stored in the reduction amount compensating device 17. Thereafter, when the rolling rollers 4, 4a are bitten in the same manner, the rolling position of the rolling rollers 3, 3a is controlled through the rolling amount control device 15 so that it becomes Si+1o.

Next, when the material 1 to be rolled goes through the rolling rollers 2 and 2a, when the rolling state tracking device 20 detects that the material 1 to be rolled goes through the rolling rollers 2 and 2a, the rolling reduction amount compensating device 17 - Control the rolling position of 3a through the rolling amount control device 15 so that it becomes Si+1b stored therein. Thereafter, the rolling amount of each rolling roller is similarly controlled each time the material 1 to be rolled goes through.

However, controlling the amount of reduction as described above causes fluctuations in the front tension and rear tension. For example, when the rolling position of the rolling roller is controlled in the closing direction, the front tension of the rolling roller increases and the rear tension of the rolling roller decreases. It is a well-known fact that this reduction in rear tension increases the plate thickness on the exit side of the rolling roller, reducing the effect of closing the rolling position.

Therefore, with the above-mentioned conventional plate thickness compensation control device that controls only the rolling reduction amount, accurate plate thickness compensation control cannot be performed due to changes in the tension between the rolling rollers. In particular, at times when the rolling condition suddenly changes, such as during sheet threading or tailing, not only is tension generated or lost rapidly, but the tension itself is also likely to fluctuate. For this reason, it is difficult to perform accurate plate thickness compensation control, and it is also difficult to reduce the amount of plate thickness off-gauge, but there are also inconveniences such as failure to bite during plate threading and breakage of the rolled material. Ta.

In this way, the threading and
During tail-off, the rolling state is different from that during steady state, such as the presence or absence of tension and the extremely slow rolling speed. Therefore, most of the off-gauge amount of the product appears in the area that is rolled during this threading and tailing.

In order to effectively deal with these differences and sudden changes in rolling conditions, the present invention not only controls the amount of reduction but also the tension value of the material to be rolled, so that the material to be rolled can be accurately rolled to the target thickness. This is an attempt at compensatory control.

Here, the amount of slight fluctuation in the rolling reduction of the rolling roller of the i-th rolling mill is ΔSi, and the resulting change in front tension is Δtif.
If the rear tension change is Δtib, then Ai = Δtif/ΔSi ……(1) Bi = Δtib/ΔSi ……(2) Ai and Bi obtained from the formula can be considered almost constant as long as the rolling schedule is the same. It is a value.

Further, there is the following relationship between the rolling reduction amount Sif and the steady rolling setting value Sio, such that the exit side plate thickness of the rolling roller of the i-th rolling mill becomes a predetermined plate thickness in the absence of forward tension.

Sio−Sif=fi・tif...(3) fi is the inlet plate thickness Hi, outlet plate thickness hi, material deformation resistance value ki, rear tension value tib of the rolling roller of the i-th rolling mill,
and a function consisting of various parameters of the rolling mill. Once the rolling mill is determined, it is a function of Hi, hi, ki, tib,
This can also be considered to be approximately constant depending on the rolling schedule. Similarly, Sib is Sib−Sio=−f′itib...(4) f′i is the inlet side plate thickness Hi, outlet side plate thickness hi, material deformation resistance value ki, forward tension value tif, and various parameters of the rolling mill, and once the rolling mill is determined, it is a function of Hi, hi, ki, and tif.

These values Sio, Sif, Sib, fi,
Calculate f′i, Ai, and Bi in advance. At the time of sheet passing, for example, the i-th rolling mill is set so that the rear tension of the i+1-th rolling mill roll, that is, the front tension tif of the i-th rolling mill roll, becomes the predetermined tension value tifo at the same time that the rolling roller of the i+1-th rolling mill bits the material 1 to be rolled. Start controlling the speed of the rolling mill rolling rollers.

In proportion to the rise of this forward tension tif, the rolling reduction amount of the rolling roller of the i-th rolling mill is controlled so that Si=Sif+fi·tif. At the same time, the speed of the rolling roller of the i-1st rolling mill is controlled in accordance with the variation (Si-Sif) Bi of the rear tension tib of the rolling roller of the i-th rolling mill due to the change in the rolling reduction amount Si.

Next, when the material to be rolled passes through the rolling roller of the i-1st rolling mill, the rolling reduction amount of the rolling roller of the i-th rolling mill is controlled by Si=Sio-fi'・tib,
At the same time, the speed of the rolling roller of the i-th rolling mill is changed to (Si−
Sio) Change the amount commensurate with Ai. These controls can compensate for variations in tension values. In addition, when the tension is established and the rolling roller is stable, the exit side plate thickness detection device is used to readjust the rolling reduction amount of the rolling roller, thereby allowing more accurate plate thickness compensation control. At this time as well, the speed is corrected in accordance with the amount of reduction adjustment.

It should be noted that the rolling rollers 2, 3, and 4 shown in the figure are located upstream from a pivot stand, that is, a rolling roller that serves as a reference speed and whose speed is prevented from fluctuating during rolling.

FIG. 2 is a block diagram showing an embodiment of the plate thickness control device of the present invention. 1 to 20 in the figure are numbered 1 in Figure 1.
This is the same as those shown with numbers 20 to 20, and in particular, the roll reduction amount compensating device 17 is provided with a circuit for transmitting the roll reduction amount to a tension compensation control device 21, which will be described later. In addition, the rolling schedule calculation device 19 contains the aforementioned influence coefficients Ai, Bi, fi, f′i between rolling and tension.
A computing device is provided. 21 is a tension compensation control device that monitors the tension value between each rolling roller;
Reference numerals 2, 23, and 24 indicate material plate thickness detecting devices on the exit side of each rolling roller, and 25, 26, and 27 indicate tension detecting devices that detect the tension value of the rolled material 1 between the respective rolling rollers.

Next, the operation will be explained. In this explanation, the symbol i is the rolling roller 3, 3a in FIG. 2, i-1 is the rolling roller 2, 2a, and i+1 is the rolling roller 4, 4.
Point to a. For example, tif indicates the front tension of the rolling rollers 3 and 3a.

Before the start of rolling, the rolling schedule calculation device 19 calculates various setting values Sio, tibo, and
tifo・Sib・Sif・Vio and influence coefficient Ai・Bi・fi・
f′i is calculated. Sio, Sif, Sib, fi, and f'i are transmitted to the reduction amount compensation device 17, and tibo, tifo, Ai, and Bi are transmitted to the tension compensation control device 21, and are stored during rolling of the same schedule.

Also, as described in Fig. 1, the i-th rolling roller is set to Sif/Vio (i-1,
The same applies to i+1.... ) Rolled material 1
When the roll is bitten by the rolling rollers 2, 2a and then by the rolling rollers 3, 3a, the tension is compensated so that the tension between the rolling rollers 2, 2a and the rolling rollers 3, 3a becomes a predetermined tension value tibo. The speed of the rolling roller rotation driving electric motor 5 is controlled by the output of the control device 21 via the speed setting device 18 and the speed control device 8. This tension value tib=ti−1f is the tension detection device 2
5.

At this time, in proportion to the detected value of the tension detection device 25,
The reduction amount compensator 17 instructs the reduction amount control device 14 to open the reduction drive device 11 by an amount of ti-1f·fi-1. Then rolling rollers 2 and 2a
The tension value tib between the rolling rollers 3 and 3a is a predetermined value.
tibo, and at the same time the rolling position of the rolling rollers 2, 2a becomes Si-1o, the tension monitoring loop between the rolling rollers 2, 2a and the rolling rollers 3, 3a is released.

After this, rolling rollers 2, 2a and rolling rollers 3, 3
A is monitored by a plate thickness detection device 22, and a deviation signal from the plate thickness detection device 22 is sent to a reduction amount control device 14 of the rolling rollers 2 and 2a through a reduction amount compensating device 17.
Output to. At the same time, in order to correct the tension fluctuation value between the rolling rollers 2, 2a and 3, 3a due to this output value ΔSi-1, the rolling rollers 2, 2a are adjusted to
A control signal is output from the tension compensation control device 21 to the speed control device 8 through the speed setting device 18 so that the speed corresponds to the amount of −1·ΔSi−1.

Next, when the material to be rolled 1 is bitten by the rolling rollers 4 and 4a, the tension value tif between the rolling rollers 3 and 3a and the rolling rollers 4 and 4a increases as well as between the rolling rollers 2 and 2a and the rolling rollers 3 and 3a. A control signal is outputted to the speed control device 9 of the rolling rollers 3 and 3a through the tension compensation control device 21 and the speed setting device 18 so that the predetermined tension value tifo is achieved. At this time, due to fluctuations in the speed of the rolling rollers 3 and 3a, the rolling rollers 2 and 2
The speeds of the rolling rollers 2 and 2a are similarly varied so that tension fluctuations do not occur between the rolling rollers 3 and 3a.

With the establishment of the tension value tif between the rolling rollers 3, 3a and 4, 4a, the rolling rollers 3, 3 are tightened by the amount of fi·tif according to the detected value of the tension detection device 26.
The amount of rolling a is controlled through the rolling amount compensating device 17 and the rolling amount controlling device 15, as in the case between the rolling rollers 2, 2a and rolling rollers 3, 3a. However, at this time, make sure that the tension between the rolling rollers 2, 2a and 3, 3a does not change (Si-
The speed of the rolling rollers 2 and 2a is controlled by an amount corresponding to Sif) Bi by the output of the tension compensation control device 21 via the speed setting device 18 and the speed control device 8. When the rolling rollers 3 and 3a and the rolling rollers 4 and 4a are in a steady state, the plate thickness detection device 23 starts monitoring the rolling rollers 2 and 2a and the rolling rollers 3 and 3a. Similar control is applied to the downstream side.

During tail-off, the material to be rolled 1 first passes through the rolling rollers 2, 2a, and at the same time the rolling roller 3.
The reduction amount compensating device 17 outputs an output to the reduction amount control device 15 so that the amount of reduction of 3a becomes Sib. At this time, in order to prevent the tension value tif between the rolling rollers 3, 3a and 4, 4a from fluctuating, an amount commensurate with Ai (Si-Sio) is applied to the speed controller 9 by the tension compensation controller 21 through the speed setting device 18. is output to. As the material 1 to be rolled passes through to the downstream side,
The rolling amount and speed of the rolling roller one upstream from the rolling roller from which the material 1 to be rolled has passed are controlled.

In the above embodiment, the rolling schedule calculation device 19 calculates the rolling position Sif at which the exit side plate thickness of the i-th rolling roller becomes a predetermined plate thickness, but the upstream rolling roller is controlled at the time of biting. Effects can also be expected if the value of Sif of the downstream rolling roller is derived and determined using the plate thickness detection device provided on the upstream side, and only the control is performed on the downstream side. Considering that it is easier to pass the plate on the downstream side than on the upstream side, this is actually simpler.

As described above, according to the plate thickness compensation control device of the present invention, the amount of reduction of the rolling roller and the tension value of the material to be rolled are controlled during the sheet passing and the bottom removal, and the reduction position compensation device controls the tension value of the material to be rolled during the sheet passing. The rolling reduction amount of the upstream rolling mill is controlled according to the tension of the tension detection device, and the rolling reduction amount of the downstream rolling mill is tightened by a predetermined value at the time of tailing, so that the plate of the material to be rolled is tightened. Thickness can be compensated easily and accurately. As a result, it is expected that the amount of plate thickness off-gauge will be reduced and production efficiency will be improved. Further, since the above-mentioned control of the reduction amount and tension value is all performed automatically, the work burden on the operator can be reduced. Furthermore, the thickness of the material to be rolled is detected for each rolling mill, and based on the detection signal, the rolling amount of each rolling mill is controlled so as not to change the tension of the material to be rolled. In addition, there are effects such as the ability to perform plate thickness compensation control with high precision.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a conventional plate thickness control device, and FIG. 2 is a block diagram showing an embodiment of the plate thickness control device of the present invention. 1... Material to be rolled, 2.2a, 3.3a, 4.
4a... Rolling roller, 5, 6, 7... Rotation drive electric motor, 8, 9, 10... Speed control device, 11.
12/13……Down drive device, 14/15/16
...Reduction amount control device, 17...Reduction amount compensation device,
18... Speed setting device, 19... Rolling schedule calculation device, 20... Rolling state tracking device, 21...
...Tension compensation control device, 22, 23, 24... Plate thickness detection device, 25, 26, 27... Tension detection device.

Claims (1)

[Scope of Claims] 1. A reduction amount compensating device for controlling the reduction amount of the rolling roller by driving a reduction drive device that adjusts the reduction amount of the rolling roller provided for each stand of the multi-stage rolling mill; A tension compensation control device that adjusts the speed of a rotary drive electric motor that drives a rolling roller and controls the rolling speed of the rolling roller to compensate for the thickness of a rolled material during sheet passing and tailing, When the material to be rolled passes through the i+1 stand, the speed of the rolling roller of the i-th stand is controlled so that the front tension of the i-th stand becomes a predetermined tension value, and the speed of the rolling roller of the i-th stand is controlled in proportion to the rise of the front tension of the i-th stand. The reduction amount Si is determined by the reduction amount compensator, Si = Sif + fi・tif However, Sif is the reduction amount in the absence of forward tension. fi is a function of the inlet side plate thickness, outlet side plate thickness, deformation resistance, and rear tension. tif is the forward It is tension. In order to control the rolling speed of the i-1st stand based on Bi (Si -Sif) However, Bi is the ratio of the rear tension change to the reduction amount change. When the material to be rolled falls through the bottom of the i-1st stand, the reduction amount Si of the i-th stand is controlled by the reduction amount compensator, Si=Sio−fi′・tib However, Sio is the quantitative setting of the reduction amount. The value fi′ is a function of the inlet plate thickness, outlet plate thickness, deformation resistance, and front tension. tib is the back tension. In order to control the rolling speed of the i-th stand based on Ai (Si-Sio ) However, Ai is the ratio of the front tension change to the reduction amount change. A plate thickness compensation control device for a multi-high rolling mill, characterized in that the control is performed based on the following.