JP3080484B2 - Rolling machine shape control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shape control device for a rolling mill.

[0002]

2. Description of the Related Art As a shape control device of a rolling mill, for example,
Those described in JP-A-55-45562, JP-A-62-214814 and the like are known. This conventional apparatus includes a shape detecting means for detecting a plate shape of a rolled material, and a calculating means for obtaining a control amount for correcting the shape of the rolled material based on data from the detecting means and outputting the control amount at a predetermined control cycle. And a plurality of shape control actuators that operate based on the control amount from the calculation means.

Referring to FIG. 3, the conventional shape control will be described by taking a roll crown actuator A and a roll bending actuator B as examples. The speeds VA and VB of the actuators A and B are set to predetermined values, respectively. Then, the control amounts ΔXiA and ΔXiA of each of the actuators A and B in a certain control cycle Ci.
It is different from XiB.

Accordingly, the movement times TiA and TA for correcting the shape of each of the actuators A and B in a certain control cycle Ci are described.
iB is also different.

[0005]

In the conventional shape control, during a certain control cycle Ci, the actuator A completes the movement of the shape control at time TiA and the actuator B completes at time TiB. When TiA and TiB are not equal, a state occurs in which the operation of one actuator A has been completed, but the other actuator B is still moving.

The shape correction is achieved when both the actuators A and B have completely moved by the control amounts ΔXiA and ΔXiB. If a delay occurs in one of them, an incomplete correction is made within the delay time. Become. That is, the delay time (T
In iB-TiA), some or all of the shape elements that should be corrected by the actuator B originally remain on the rolled material. In some cases, this remaining shape element has a bad influence on the rolled material or rolling operation.

Accordingly, the present invention provides a shape control device for a rolling mill that enables a plurality of actuators to complete their movements at the same time, eliminates residual shape elements of delayed actuators, and enables highly accurate plate shape control. The purpose is to provide.

[0008]

In order to achieve the above object, the present invention takes the following measures. That is, a feature of the present invention is that a shape detecting means for detecting a plate shape of a rolled material, and a control amount for correcting the shape of the rolled material based on data from the detecting means are obtained at predetermined control intervals. And a plurality of shape control actuators that operate based on the control amount from the calculation means, wherein the operation of each shape control actuator is terminated within the control cycle. The present invention is characterized in that an actuator speed adjusting device for controlling the speed of each actuator is provided so that the times become equal.

[0009]

According to the present invention, the speed of each actuator is controlled by the actuator speed adjusting device so that the operation end time of each shape control actuator becomes equal within the control cycle. That is, in the past, the speed of each actuator was set to a specific constant, but in the present invention, the speed of each actuator was made variable,
Since the speed is controlled so that the operation time of each actuator is the same, no operation delay occurs, and the residual shape element of the slow moving actuator is eliminated.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, a rolling mill 1 is configured as a multi-high rolling mill for plate rolling having a pair of upper and lower work rolls, an intermediate roll supporting the work roll, a backup roll supporting the intermediate roll, and the like. Has a simplified representation of its structure.

A rolled material 2 is rolled between a pair of upper and lower work rolls of the rolling mill 1. The rolled material 2 is a plate material such as a thin steel plate. The rolling mill 1 is provided with a plurality of shape control actuators for controlling the plate shape of the rolled material 2. These actuators are, for example, an actuator that shifts the intermediate roll in the axial direction, an actuator that applies bending to the intermediate roll, an actuator that controls the crown of the backup roll, and the like. Each actuator is composed of a motor, a hydraulic cylinder, and the like. In the drawing, two types of A and B actuators 3 and 4 are representatively shown.

Downstream of the rolling mill 1, a shape detecting means 5 for detecting the plate shape of the rolled material 2 is provided. The shape detecting means 5 is constituted by a plurality of shape sensors arranged in the width direction of the rolled material 2. The shape detecting means 5 and the actuators 3 and 4 are electrically connected by a calculating means 6. This calculation means 6
Are connected to a mill controller 7.

The calculation means 6 has a shape detection computer 8, a shape control computer 9, and an actuator speed adjusting device 10. The shape detection computer 8 calculates the elongation (shape) of the rolled material 2 in the width direction from the shape element detected by the shape detection means 5.
Is what you want. The shape control computer 9 calculates each control amount in the control cycle of each of the actuators 3 and 4 from the width direction shape of the rolled material 2 obtained by the shape detection computer 8 and a preset target shape. A control amount determining means 11 for determining, a maximum speed calculating means 12 for calculating a maximum moving speed of each of the actuators 3 and 4, a control amount limiting means 13 for setting the control amount to a certain value or less by the maximum moving speed. Having.

FIG. 2 shows a processing procedure in the shape control computer 9. In phase 1 of the figure,
A pre-process for performing the control calculation is performed. That is, the maximum moving speed of each of the actuators 3, 4 is calculated by the maximum speed calculating means 12. The maximum moving speed (Max) is a maximum speed at which each of the actuators 3 and 4 can move under a certain condition, and is a function of the maximum driving force (F), the rolling force (P), and the rolling speed (V) for the actuator. Is defined by

That is, the maximum movement speed Max-A of the A actuator 3 is: Max-A = f (F, P, V) The maximum movement speed Max-B of the B actuator 4 is: Max-B = g (F, P , V). These functions are given in advance.

Here, data from the mill controller 7 is used for F, P and V. In phase 2, the control amount determining means 11 calculates the control amounts ΔXiA and ΔXiB of each of the actuators 3 and 4. In the phase 3, it is determined whether or not the control amount obtained in the phase 2 exceeds the limit of the maximum moving speed obtained in the phase 1.

[0017] Here, T is the movement time of the actuator and is set in advance as a time within the control cycle. In this example,
The control cycle is T. If all the control amounts satisfy the conditional expression, the process proceeds to phase 5, and the control amounts are input to the actuator speed adjusting device 10.

If at least one of the controlled variables does not satisfy the conditional expression, the actuator cannot move within the control period for the controlled variable. The control amount is limited as follows. That is, when the control amount of the actuator does not satisfy the above-mentioned conditional expression, Di = ΔXi / Ri is obtained. Here, Di is the ratio of the control amount to the constraint value, and Ri is the limit value at which the actuator can move within the control cycle.

When the values of Di are all Di ≦ 1, the control amounts of all actuators are determined. Even if the value of Di is one, if Di> 1, only the control amount of the actuator having the maximum value of Di is determined as ΔXi = Ri, and actuators other than the actuator are set as control amount calculation targets. Returning to the phase 2, the control amount is recalculated.

The procedure for determining the control amount is repeated until there is no more actuator for which the control amount is to be calculated. The control amount from the shape control computer 9 is input to the actuator speed adjusting device 10, and the speed adjusting device 10 controls the speed of each actuator 3, 4 so that the movement completion time of each actuator 3, 4 becomes the same. Control.

That is, the moving speeds VA,
VB is output to each of the actuators 3 and 4 as VA = ΔXiA / T VB = ΔXiB / T. Since each of the actuators 3 and 4 moves at the aforementioned speed, the movement time of both actuators 3 and 4 becomes the same.

Therefore, according to the above-described embodiment, there is no residual shape element of the slow-moving actuator which occurs between the actuator which finishes moving early and the actuator which finishes moving slowly, which has conventionally occurred. Further, an actuator having a large shape correcting capability has a large amount of variation with respect to the plate thickness. When the moving speed of the actuator is high, the amount of change with respect to the plate thickness can be reduced by changing the moving speed of the actuator.

That is, since the moving speed is high, the ratio of the moving time to the control cycle is smaller than that of the other actuators. Therefore, in the shape control device according to the present invention, the moving speed of this actuator is smaller than the rate at which the moving speeds of the other actuators are reduced. At this time, the amount of fluctuation of the plate thickness per unit time by the actuator is reduced, and the speed of input fluctuation to the plate thickness control is reduced.

As a result, the accuracy of the product thickness is improved. Note that the present invention is not limited to the above embodiment, and for example, the moving time T of the actuator can be determined as follows. (ΔXiA / Max-A) and (ΔXiB /
T is the larger value of Max-B). That is, the actuator movement time when the actuator moves at the maximum movement speed is obtained for each actuator, and the maximum value among them is set as the control cycle. When T is determined in this manner, the control cycle is shortened and the control accuracy is improved.

[0025]

According to the present invention, since each actuator moves synchronously within the control period, the shape correction amount of the actuator also synchronizes, and the actuator which finishes moving earlier and which moves earlier, which has occurred conventionally, moves slowly. There is no residual shape element of the actuator that moves slowly, which is generated between the actuators to be completed, and the shape control can be performed with high accuracy.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart showing a processing procedure in a shape control computer.

FIG. 3 is an explanatory diagram showing a moving state of each actuator by conventional control.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rolling machine 2 Rolled material 3 Shape control actuator 4 Shape control actuator 5 Shape detection means 6 Calculation means 10 Actuator speed adjusting device

Claims (1)

(57) [Claims] 1. A shape detecting means for detecting a sheet shape of a rolled material, and a calculating means for obtaining a control amount for correcting the shape of the rolled material based on data from the detecting means and outputting the control amount at a predetermined control cycle. A shape control device for a rolling mill, comprising: a plurality of shape control actuators that operate based on the control amount from the calculation means.In the control cycle, the operation end time of each shape control actuator is equalized. A shape control device for a rolling mill, comprising an actuator speed adjusting device for controlling the speed of each actuator.