JPS61255710A - Shape control device for cluster rolling mill - Google Patents

Abstract

PURPOSE:To improve productivity by presetting the pattern and quantity of a backup roll crown according to rolling conditions and controlling rolling down leveling and roll bender in accordance with the detected value of a sheet shape. CONSTITUTION:Backup rolls 3 of a cluster rolling mill 1 are made into a split construction and can be pushed out toward and arrow direction. A shape detector 10, disposed on the outlet side of the mill 1, detects the shape of a rolling material 2 and outputs the elongation and strain distribution beta(x) in the transverse direction of the sheet. A preset calculating device 14 presets the pattern and quantity of the optimum backup roll crown from the rolling conditions. The elongation and strain distribution beta(x) during rolling is then inputted to an orthogonal function calculating device 11 which controls a primary mode coefft. A1 and secondary mode coefft. A2 so as to make the same coincident with target values A*1, A*2. The improvement in the productivity is made possible to meet all the rolling conditions.

Description

[Detailed description of the invention] <Industrial application field> The present invention relates to a shape control device for a cluster rolling mill.

<Prior Art> As a conventional shape control technology for a rolling mill, a method of using a roll crown and a roll bender in combination in a four-high rolling mill is known. this is.

In this method, work rolls with various roll crowns are prepared in advance, the most suitable roll is selected according to rolling conditions, and fine adjustments and corrections to the shape during rolling are performed by a roll bender. However, in this method (110-rupender), because the control range is limited, it is only possible to change the rolling conditions within a narrow range for the selected work roll. Therefore, it is not possible to freely determine the rolling schedule. Productivity is bad because there is no such thing.(2)
Since the roll car 1 is simple, it is impossible to control the composite elongation, and it is difficult to obtain a good plate shape under all rolling conditions.

<Problems to be Solved by the Invention> In place of the conventional four-high rolling mill which has the above-mentioned drawbacks (1) and (2), the present invention uses a cluster rolling mill to achieve high productivity and all It is an object of the present invention to provide an apparatus that can perform good shape control regarding rolling conditions.

Means for Solving the Problems> The shape control device for a cluster rolling mill according to the present invention that achieves the above object calculates the pattern and amount of puncture roll crown suitable for the rolling conditions in response to input rolling conditions. 4. A means for presetting, a means for detecting the plate shape after rolling, and a means for determining the strain distribution of the plate shape from the detected value of the plate shape.
means for calculating each coefficient of the 4th order orthogonal function; means for controlling the rolling leveling so that the 1st order coefficient among the coefficients of the 4th order orthogonal function matches the target value; and the 2nd order coefficient of the 4th order orthogonal function. and means for controlling the roll bender so that the roll bender matches the target value. “Function” In the cluster rolling mill, the puncture-up roll crown can be set in any pattern and shape, and it is possible to apply a pending force to the roll between 6!l, t &lF' with a roll bender, so the puncture-up roll crown can be set as desired. The combination of adjustment and pending force adjustment allows for shape control over a wide range of rolling conditions.

On the other hand, when calculating each coefficient of a quartic orthogonal function corresponding to the strain distribution of the plate shape from the detected value of the plate shape after rolling, the first-order coefficient represents the magnitude of one-sided elongation, and the second-order coefficient represents the magnitude of medium elongation and Indicates the amount of edge elongation. Further, rolling leveling (creating a roll gap between the driving side and the working side) affects the size of one-sided elongation, and the pending force affects mid-elongation and edge elongation. From the above, calculate and preset the backup roll cracking pattern and IT-rolling conditions to suit the rolling conditions, control the rolling leveling so that the primary coefficient becomes the target value, and By controlling the roll bender so that the coefficient of is also the target value, high productivity and a desired plate shape can be obtained under all rolling conditions.

Example of implementation An embodiment of the present invention will be described with reference to FIGS. 1 to 4.

FIG. 1 is a block diagram showing the configuration of an apparatus according to an embodiment of the present invention, where 1 is a cluster rolling machine and 2 is a rolled material. First, explain the cluster rolling machine: Sult, backup roll 3,
An intermediate roll 4, a work roll 5, and a small-diameter backup roll 6 are arranged in a cluster as shown in the figure.
The backup roll 3 has a divided structure as shown in Figure @2. In addition, each of the divided backup rolls can be pushed out in the direction of the arrow shown in Figure 1 by a drive device (not shown), and the backup roll crack can be set in any pattern and negative. . Furthermore, the pending force can be applied to the intermediate roll 4 by the roll benders 21 and 22 shown in FIG. It has become.

The object of the present invention is to fully utilize the excellent shape control characteristics of a cluster rolling mill having such characteristics.

In FIG. 1, reference numeral 7 denotes a backup roll crown adjustment system, which sets the crown 97 of the pack-and-roll 3 to an arbitrary pattern and amount by commands from a preset calculation device 140. The preset calculation device 14 calculates the butter y and amount of the backup roll cracker suitable for the rolling conditions according to the input rolling conditions. Further, 8 is a roll bender system which sets the pending force of the roll bender 21, 22 to an arbitrary value according to a command from the controller 13. Further, reference numeral 9 denotes a screw down leveling system, which levels the screw down device (not shown) according to instructions from a controller 12. In addition, lO is a shape detector that detects the shape of the rolled material 2 and detects the width direction position
(both ends are normalized to ±1) and the elongation strain distribution β (element) is output. Also, the orthogonal function calculation device 11 calculates each coefficient A.-A4 of the orthogonal function using equation (1).

However, ψ0 to ψ4 are quadratic intersection functions, and each (2
) to (6).

ψ. (xl-a (21ψ
, (x) = bx (31
g+2(x5 = ax” + d
(419) 306 = ax” + Lx
(5194 bodies)-gx'+hx"+k
(6) Also, the coefficients a − k in equations (2) to (6) are determined by the orthonormal condition of equation (7).

Coefficient A of the orthogonal function obtained using the above method. -A4 is used to express the elongation strain distribution β in the plate width direction as shown in equation (8).

β(Kaiyu A0ψ.+A0ψ□+A2ψ2+A3ψ3+A
4ψ4(8) or equation (8) is expressed as shown in FIG.

As can be seen from equation (8) and FIG. 3, the coefficient A8 represents the magnitude of one-sided press, and is defined as a first-order mode coefficient. The coefficient A2 represents the magnitude of the middle elongation and edge elongation, and is defined as 6D, a second-order mode coefficient. The coefficient A3 represents the magnitude of asymmetric elongation and is defined as the third-order mode coefficient. Coefficient A4 represents the middle end extension and the size of the quarter buckle, and is defined as a fourth mode coefficient. The coefficient A0 has no physical meaning here.

Moreover, FIGS. 4(a) and 4(b) are experimental data showing the relationship between the roll bender, the rolling leveling, and the mode coefficients A8 to A4. In Fig. 4, (a) shows the pending force and the second-order and fourth-order mode coefficients A2 HA4
υ, and as the pending force increases, the secondary mode coefficient A2 changes from positive to negative, that is, from edge elongation to medium elongation. It can be seen from FIG. 4(a) that the secondary mode coefficient A2 can be controlled by operating the roll bender. It can also be seen that if control is performed so that A2=0, the fourth-order mode coefficient becomes A4ΦO, and a flat shape can be obtained. However, in order to obtain A4+O when A2=0, it is necessary to set the above-mentioned backup roll crown pattern in advance to the next optimal pattern according to the rolling conditions, especially the strip width. If the pattern is not optimal, A4 will not become so small even if A2 is controlled to 0, and a good 7-rat shape will not be obtained. In Fig. 4, (b) shows the relationship between the reduction leveling and the first and third mode coefficients AnyA3.As shown in Fig. 4(b), by operating the reduction leveling,
Next mote: It can be seen that the coefficient A1 can be controlled.

Furthermore, it can be seen that by controlling A1=0, the third-order mode coefficient also becomes A3ΦO.

The controller 12 performs appropriate arithmetic processing, such as PI calculation, on the difference between the target value A14) of the primary mode coefficient and the detected value Al of the primary mode coefficient by calculation, and the reduction repeller outputs a command value to the system 9. It is something to do. Similarly, the controller 13 outputs a command value to the roll bender servo system 8 from the target value A2' of the secondary mode coefficient and the calculated secondary mode coefficient detected value A2. Further, the preset calculation device 14 calculates a crown adjustment pattern and amount suitable for the rolling conditions, and outputs a command value for the backup roll crown adjustment servo system 70. Here, the optimal pattern is a pattern such that A4-'0 when A2=0, as described above, and is determined by the rolling conditions, especially the sheet width. Well, the optimal amount is A when the pending force is the initial setting value, for example, the middle value of the pending force adjustment range.
It is a value such that 2=0, and is determined by the rolling conditions, especially the rolling blade. The relationship between rolling conditions and the optimal pattern and amount of backup roll crown can be experimentally determined in advance.
It is also possible to calculate using a mathematical model.

The operation of the apparatus in the above embodiment is as follows: First, before rolling starts, rolling conditions are input into the preset calculation device 14, and the optimal backup roll crown pattern and amount are calculated by the method described above, and the pack-and-roll crown adjustment servo is operated. Series 7
command to preset the Punk Up Roll Crown.

Next, during rolling, the elongation strain distribution β (element) in the board width Calculate the first mode coefficient A2, and calculate the first mode and the second mode coefficient A2.
Obtain the detected value of the next mode coefficient. In addition, for the primary mode, A14I given as the target value and the detected value Al
The difference between the
Feedback control is performed so that 1”=A, .

Similarly, for the secondary mode, the target value A, * and the detected value A2
The difference between the roll bender 2-
& system 8, and performs feedback control so that A2"=A2. Through the above operations, for example, the target value AI
If " = A," = 0, then a flat shape can be obtained.

<Effects of the Invention> (1) According to the present invention, it is possible to precent the optimal pack-and-roll crown pattern and amount for all rolling conditions, so the rolling schedule can be freely determined. High productivity.

(2) Backup roll crown preset and mode coefficient A1. In combination with the feedback-control of A2, p, the mode coefficient A0 under all rolling conditions
~A4 can be set to a target value, for example, 0, and a good plate shape can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing a simple embodiment of the present invention, Fig. 2 is a schematic diagram of the roll section of a cluster rolling mill, Fig. 3 is a conceptual diagram of a 4th order cross function, Fig. 4 (a), ( b) is a graph of experimental data representing the shape control characteristics of the cluster rolling mill. In the drawing, 1...Cluster rolling mill, 2...Rolled material, 3...
Backup roll, 4... Intermediate roll, 5...
・Work roll, 6...Small diameter backup lower...Punk unroll crank 9 adjustment servo system, 8.
・Roll bending system, 9 ・Dressing level sensor 10 ・Shape detector, 11 ・Orthogonal function calculation device, 12 ・Control 5, 13 ・
... Controller, 14... Preset calculation device,
21... Roll bender, 22... Roll penta

Claims (1)

[Claims] A means for calculating and presetting the pattern and amount of backup roll crown suitable for the rolling conditions in response to the input of rolling conditions, a means for detecting the shape of the plate after rolling, and a means for determining the strain distribution of the plate shape from the detected value of the plate shape. means for calculating each coefficient of the corresponding quartic orthogonal function, and one of the coefficients of the quartic orthogonal function;
A cluster rolling mill comprising means for controlling rolling reduction leveling so that the next coefficient matches the target value, and means for controlling the roll bender so that the second-order coefficient of the fourth-order orthogonal function matches the target value. shape control device.