JPH1024306A - Device for controlling cold rolling - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the degradation of the accuracy of thickness of a material to be rolled at the time of acceleration/deceleration even when conditions/ environments such as the material and thickness of the material to be rolled are variously changed. SOLUTION: When forward slip is expressed by (f), the relationship of, the circumferential speed Vi of roll and the outlet-side speed Vo is expressed by Vo=Vi(1+f). At the time of acceleration/deceleration, the disturbances due to the variation in the coefficient of friction and variation in the thickness of an oil film is appeared as the fluctuation in the outlet-side speed Vo and the relationship of the above-equation is not held. The outlet-side speed Vo1 at this time is detected with sheet speedometers 36-40 and those detected signals are outputted to thickness controllers 26-30. The detected signals from the sheet speedometer 36-39 are inputted to the thickness controllers 26-29, the control signals which are outputted to roll gap position controllers 31-34 are corrected so as to be Vo1=Vo and the roll paps of rolling rolls 1-4 are adjusted. The control signals which are outputted to a motor speed controller 14 are also corrected with the thickness controller 30 and the speed of the rolling roll 5 is adjusted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cold rolling control device.

[0002]

2. Description of the Related Art FIG. 3 is a block diagram showing a configuration of a conventional apparatus. In this figure, the material to be rolled W is NO. 1 to
NO. The stand 5 unwinds from the left to the right in the figure. Each stand has a motor 6-1
It has rolling rolls 1 to 5 driven to rotate by zero. Motors 6 to 10 are motor speed controllers 11 to 14
The motor speed controllers 11 to 14 are provided with control signals from tension controllers 15 to 18. Tension control device 15 ~
Reference numeral 18 inputs detection signals from the stand-to-stand tension control measuring devices 19 to 22, and outputs control signals to the motor speed controllers 11 to 14 based on a deviation between the detection signals and a predetermined set value. It has become.

The roll gaps of the rolling rolls 1 to 5 are controlled by roll gap position controllers 31 to 35. Roll gap position control devices 31 to
A control signal is given to the control unit 34 from the thickness control units 26 to 29. These thickness control devices 26-2
Reference numeral 9 designates input of detection signals from the thickness measuring devices 23 and 24, and outputs a control signal to the thickness control devices 26 to 29 based on a deviation between the detection signal and a predetermined set value. It has become. In addition, NO. Only at the five stands, the detection signal from the thickness measuring device 25 is input to the thickness pressure control device 30, and the thickness control device 30 outputs the thickness control signal to the motor speed control device 14. Thus, the thickness control is performed.

[0004] Next, the operation of the cold rolling control device configured as described above will be schematically described. In the cold rolling mill, the effect of the change in roll gap on the product sheet thickness depends on the NO. Of the final stand closest to the product. NO. Of the stand farthest than 5 stands. One stand is larger.
Such a phenomenon is a phenomenon caused by the rolling factors affecting each other using the tension between stands as a medium, and is peculiar to continuous rolling. When continuous rolling is performed in a steady state, the volume speed (sheet width × sheet thickness × sheet speed) is constant at any location of the rolling mill.

A feature of the cold rolling control is that rolling is performed using the tension between stands, and the rolling characteristics greatly change depending on how the tension between stands is handled. The coefficient of influence on the product sheet thickness when the tension between stands is controlled to a constant value by adjusting the roll speed is opposite to the above-described rolling characteristics. That is, NO. The influence of the change in the gap of one stand on the product thickness is small, and the NO. The effect increases as the distance to the five stands increases.

When the material thickness increases stepwise during steady rolling (in a state where rolling is performed at a constant speed), the thickness of the stand at which the material thickness variation portion arrives increases most greatly, and the thickness of the stand increases. When the changing portion arrives at the next stand, the inter-stand tension decreases, so that the plate thickness further increases.

[0007] NO. When the roll gap of one stand is enlarged, NO. The exit plate thickness of one stand increases, and the plate thickness continues to increase until the point where the plate thickness change portion passes through each stand. Then, the tension on the rear side (upstream side) of the stand where the plate thickness changing portion has arrived decreases.

[0008] NO. When the roll gap of the five stands is enlarged, the moment the NO. Although the outlet plate thickness of the 5th stand increases, the NO. 4 to NO. Since the inter-stand tension of the five stands also increases, the NO. The outlet plate thickness of the four stands decreased, and NO. The exit thickness of the five stands does not change much in the end.

NO. When the roll speed of one stand is increased, NO. 1 to NO. When the tension between the stands of the two stands decreases, NO. The outlet plate thickness of one stand increases. Then, the thickness variation propagates to the final stand, and finally the NO. The exit plate thickness of the five stands increases, and the tension between stands decreases.

The intermediate stand NO. When the speed of the three stands is increased, NO. 3 to NO. The inter-stand tension of the four stands decreased, and conversely, the NO. 2 to NO. The tension between the three stands increases. At this time, NO. The exit plate thickness of the five stands changes transiently, but hardly changes eventually.

NO. If you increase the speed of 5 stands,
NO. 4 to NO. The inter-stand tension of the five stands increased, and NO. The exit thickness of the five stands is reduced. At this time, NO. Since the exit plate thickness of the four stands also decreases, N
O. The outlet thickness change part in the four stands is NO. After arriving at the 5th stand, NO. The exit plate thickness of the five stands converges to a constant value.

[0012]

The conventional cold rolling control apparatus generally performs the above-described operations, and the control state is relatively stable during steady rolling, that is, while the rolling speed is kept constant. And the plate thickness accuracy is good.

However, when the rolling roll is accelerated or decelerated, the rolling state changes and the accuracy of the thickness is reduced. In other words, in the case of cold rolling, the product thickness decreases when acceleration is performed,
Deceleration increases the product thickness. This phenomenon is mainly caused by (1) a change in friction coefficient due to a change in rolling speed, and (2)
This is caused by a change in the oil film thickness of the backup roll oil film bearing due to a change in the rolling speed. These changes are
Since they interact with each other through inter-stand tension, they exhibit complex behavior.

Conventionally, an appropriate roll gap and an inter-stand tension have been determined from an empirical rule in order to prevent a decrease in sheet thickness accuracy during acceleration / deceleration.
It changes according to the material of the material to be rolled, the plate thickness, and various other conditions. Therefore, it has been difficult for the conventional apparatus to improve the rolling accuracy of the material to be rolled over a certain level.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a cold rolling control device capable of preventing a reduction in sheet thickness accuracy of a material to be rolled during acceleration / deceleration.

[0016]

As a means for solving the above-mentioned problems, the invention according to the first aspect of the present invention is directed to a method for controlling the tension between the stands and the roll gap control of the rolling rolls. In a cold rolling control device that performs pressure control, a sheet speed meter provided on an outlet side of each stand and detects a speed of a material to be rolled, and a roll gap control during acceleration and deceleration of the rolling roll, the sheet speed meter And a roll gap position control device that takes in the detection signal from the roll gap control device.

According to a second aspect of the present invention, in the first aspect of the present invention, there is provided an acceleration / deceleration detecting means for detecting that the roll is accelerated / decelerated, and the acceleration / deceleration detecting means detects an acceleration / deceleration state. Only in this case, the roll gap position control device takes in a detection signal from the sheet speed meter.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the sheet speed meter detects the speed of the material to be rolled by emitting laser light. .

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram illustrating a configuration of the cold rolling control device of the present embodiment. FIG. 1 differs from FIG. 3 in that sheet speedometers 36 to 40 are provided on the respective exit sides of the rolling rolls 1 to 5. These speedometers 36 to 40 are
This is a type in which a laser beam is emitted to the material to be rolled W to detect the speed of the material to be rolled W, but another type may be used. The detection signals from the sheet speedometers 36 to 39 are input to sheet thickness controllers 26 to 29 which provide control signals to the roll gap position controllers 31 to 34. The detection signal of the plate speedometer 40 provided on the exit side of the five stands is input to a plate thickness control device 30 that provides a control signal to the motor speed control device 14. Then, the sheet thickness control devices 26 to 30 are adapted to correct control signals for sheet thickness control in a normal state based on the sheet speed detection signals input thereto.

FIG. 2 is an explanatory diagram showing a state of the incoming side plate thickness Hi and the outgoing side plate thickness hi of the rolling roll, and showing the relationship between the roll peripheral speed Vi and the outgoing side speed Vo. Here, assuming that f is the advance rate, the delivery speed Vo is represented by Vo = Vi (1 + f) (1). Then, the disturbance caused by the change in the friction coefficient and the change in the oil film thickness during acceleration / deceleration appears as a change in the outlet speed Vo, and the relationship of the expression (1) is not established. The sheet speedometers 36 to 40 indicate the delivery speed Vo at this time.
1 is detected, and the detection signal is output to the sheet thickness controllers 26 to 30.

The thickness control devices 26 to 29 are provided with
The control signal outputted from the control unit 39 is input to the roll gap position controllers 31 to 34 so that Vo1 = Vo, and the roll gaps of the rolling rolls 1 to 4 are adjusted. The sheet thickness controller 30 also receives the detection signal from the sheet speed meter 40, corrects the control signal output to the motor speed controller 14 so that Vo1 = Vo, Adjust speed.

Conventionally, in order to prevent a decrease in sheet thickness accuracy at the time of acceleration / deceleration, the operation at the time of acceleration / deceleration is performed using a roll gap value or a motor speed value determined from an empirical rule based on past data. However, since the degree of disturbance varies depending on various conditions, as described above, sufficient thickness accuracy cannot be secured with this. However, as described above, correcting the control signal using the detection signal of the sheet speedometer means adjusting the roll gap value and the motor speed value according to the actual conditions and environment. , No matter how conditions or environment change,
Sufficient thickness accuracy can be ensured.

The thickness control devices 26 to 30 are always
The control may be performed by taking in the detection signals of the plate speedometers 36 to 40, but from the viewpoint of control stability, the detection signal of the plate speedometers 36 to 40 may be taken in only at the time of acceleration / deceleration. For example, acceleration / deceleration detecting means for detecting that the acceleration / deceleration control will be performed soon by inputting an acceleration / deceleration command signal or the like is provided, and based on the detection by the acceleration / deceleration detecting means, the detection signals of the sheet speedometers 36 to 40 are taken in You can do so.

[0024]

As described above, according to the present invention, even if the conditions and environment such as the material and the thickness of the material to be rolled are variously changed, the accuracy of the thickness of the material to be rolled is reduced during acceleration / deceleration. It is possible to provide a cold rolling control device capable of preventing the cold rolling.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a cold rolling control device of the present invention.

FIG. 2 is an explanatory diagram showing a relationship between a roll peripheral speed Vi and a delivery speed Vo.

FIG. 3 is a block diagram showing a configuration of a conventional cold rolling control device.

[Explanation of symbols]

 1-5 Rolling roll 6-10 Motor 11-14 Motor speed controller 15-18 Tension controller 19-22 Stand-to-stand tension controller 23-25 Plate thickness measuring device 26-30 Plate thickness controller 31-35 Roll gap position Controller 36-40 Sheet speed meter W Material to be rolled

Claims (3)

[Claims] 1. A cold rolling control device for controlling a sheet pressure of a material to be rolled by using a tension control between stands and a roll gap control of a rolling roll in combination. A sheet speed meter that detects the speed of the material, and a roll gap position control device that performs roll gap control during acceleration / deceleration of the rolling roll by taking in a detection signal from the sheet speed meter. Cold rolling control device. 2. The cold rolling control device according to claim 1, further comprising acceleration / deceleration detecting means for detecting that the roll is accelerated / decelerated, wherein said acceleration / deceleration detecting means detects an acceleration / deceleration state. only,
The roll gap position control device captures a detection signal from the plate speedometer, wherein: 3. The cold rolling control device according to claim 1, wherein the sheet speed meter detects the speed of the material to be rolled by emitting laser light. Rolling control device.