JPH11123427A - Method for controlling shape of rolled stock and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the magnitude of cross buckle constant over the entire length of a rolled stock by adjusting tension on the outlet side of a rolling mill in accordance with rolling speed. SOLUTION: The rolled stock 1 is rolled with a temper mill 2 and the tension on the outlet side is detected with a tension detector 8. A rolling speed detector 3 is attached on one of the work rolls of the temper mill 2. The rolling speed detected with this detector is transduced into a speed signal with a rolling-speed signal transducer 4 and inputted into a cross buckle storage/arithmetic unit 5. The calculation of proper tension is executed with this arithmetic unit 5. The tension value is fetched in a tension controller 6 as an output signal. In the tension controller 6, a tension control mechanism 7 is controlled based on the inputted tension value and necessary tension is impressed on the rolled stock 1. The pass angle of the rolled stock on the outlet side of the rolling mill is adjusted in accordance with the tension on the outlet side of the rolling mill. In the arithmetic unit 5, the tension value is calculated on the basis of the target value which is set in a cross buckle target value setting part 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to shape control in the rolling of a rolled material such as a metal strip, and more particularly to shape control on the exit side of a temper rolling mill having about one or two stands. Provided is a shape control method and apparatus suitable for controlling at least one of directional warpage.

[0002]

2. Description of the Related Art In general, in a temper rolling mill, a reduction of about 1% is applied for the purpose of preventing stretcher strain after cold rolling and annealing, imparting appropriate sheet surface roughness, and correcting the shape. Perform quality rolling. However, because of this, compressive residual stress occurs in the surface layer on the front and back surfaces of the rolled material after temper rolling, and if the residual distribution is not uniform, the cross-buckle where the plate surface of the rolled material becomes bellows, warpage in the rolling direction of the rolled material Shape defects such as (warpage in the L direction) occur.

[0003] In temper rolling, it is required that each of these shape defects be within a predetermined standard level. Regarding the L-direction warpage, an auxiliary roll that is provided on the exit side of the temper rolling mill and that can correct the warpage by adjusting the height of the rolled material from the rolling line by changing the roll height, for example, It is known to correct with an anti-corrugated roll described below.

[0004] It is known that the cross buckle is mainly caused by a buckling phenomenon caused by the roll constraining the spread of the rolled material in the roll bite in the plate width direction. It is known that the generation of this cross buckle can be controlled by adjusting the final stand rolling force of the temper rolling mill and adjusting the rolling mill exit side tension. For example, JP-A-7-24511
Japanese Patent Application Publication No. 2004-122,086 discloses that the cross buckle is adjusted by adjusting the roll output side tension or the roll reduction force based on the difference between the values measured by the strip width measuring device installed on the roll entry side and the roll exit side of the temper rolling mill. Is disclosed.

Here, the size of the cross buckle means a cross-sectional profile in the width direction when a sample of a rolled material is taken and the sample is allowed to stand on a horizontal plane, and the measured peak value or peak value / wave value is measured. Is defined by the pitch of
By the way, many temper rolling mills are batch mills, and it is necessary to accelerate / decelerate the rolling speed at the leading and trailing ends of the rolled material. In addition, in the in-line temper rolling mill applied in the continuous annealing furnace, since the transport speed of the rolled material in the annealing furnace needs to be constant even during the work roll change operation of the rolling mill, a looper is provided at the entrance side of the temper rolling mill. Is installed. for that reason,
Even in the in-line temper rolling mill, the processing is not performed at a constant speed, and a state where the speed is reduced from the steady speed can occur.

Here, if the temper rolling deviates from the steady speed, a difference occurs in the strain rate, and the shape of both the L-direction warp and the cross buckle changes, leading to quality deterioration and yield reduction. It is a problem. As a method of performing appropriate shape control in response to such a change in the rolling speed, Japanese Patent Application Laid-Open No. 61-9882 discloses a method of controlling the shape of the anti-corrugated roll disposed on the exit side of the rolling mill by adjusting the skin pass speed (control). For example, a method of controlling the rolling force according to the rolling speed is disclosed in Japanese Patent Application Laid-Open No. H4-224010 regarding the cross buckle.

[0007]

SUMMARY OF THE INVENTION However, Japanese Patent Application Laid-Open No. 4-2240
According to the method disclosed in Japanese Patent Publication No. 10, there is a possibility that the plate thickness may deviate from the target value, and if the plate thickness control system interferes with the rolling force control for the correction, the cross buckle control itself may lack stability. is there. In addition, the behavior of the occurrence of other shape defects, for example, L warpage, is greatly affected by the change in the rolling force, and the effect of the rolling force on the warpage is relatively unstable.

On the other hand, in the method disclosed in Japanese Patent Publication No. 61-9882, although it seems that some kind of cross buckle control is required depending on the rolling speed, the optimum control taking into account the influence of such control is considered. It does not provide a means. The present invention solves the above problems, and provides a rolling mill exit side tension control method and apparatus capable of stabilizing the size of a cross buckle in temper rolling over the entire length of a rolled material even if the rolling speed changes. One purpose. At this time,
In particular, when the rolling mill exit side tension is increased when the rolling speed is low, the L-direction warpage may become larger than an allowable range. However, this problem is solved and the L-direction warpage is simultaneously reduced over the entire length of the rolled material. The second purpose is to stabilize

That is, according to the present invention, it is possible to provide a shape control method and apparatus capable of simultaneously controlling both the L-direction warpage and the cross buckle.

[0010]

SUMMARY OF THE INVENTION The present invention provides a method for controlling the shape of a rolled material, wherein the shape of the rolled material is controlled by adjusting the tension at the exit of a rolling mill according to the rolling speed. Solves the above problem. Further, in the shape control method of the rolled material for controlling the rolling mill exit side tension according to the target cross buckle amount, the relationship between the target cross buckle amount and the rolling mill exit side tension is adjusted according to the rolling speed, The object is achieved by providing a method for controlling the shape of a rolled material, which is characterized by controlling the shape of the rolled material.

The shape control method for a rolled material is characterized in that the shape control of the rolled material is performed by adjusting the pass angle of the rolled material on the outlet side of the rolling mill in accordance with the tension on the rolling mill outlet side. Has been resolved. Further, the shape of the rolled material is controlled by adjusting the rolling mill exit side tension in accordance with the rolling speed, and adjusting the pass angle of the rolled material on the rolling mill exit side in accordance with the rolling mill exit side tension. The above problem is solved by a rolled material shape control method characterized by the following.

As an apparatus of the present invention, there is provided a roll shape control apparatus having at least a means for adjusting a rolling mill exit side tension, comprising: a rolling speed detecting means for detecting a rolling speed of a rolling mill; A cross buckle storage calculating device for calculating an appropriate tension at which the cross buckle height becomes equal to or less than a predetermined target value in accordance with the rolling speed detected in the step (a), and means for adjusting the calculated appropriate tension to the output side tension as a tension control mechanism. The above-mentioned problem is solved by applying a shape control device for a rolled material, characterized by having a tension control device for controlling the tension by outputting to a roll.

A rolled material shape control device having at least a means for adjusting a pass angle of the rolled material at a rolling mill exit side, wherein a tension detector for detecting a rolling mill exit side tension; An L-direction warp amount storage and arithmetic unit that calculates an appropriate pass angle of a rolled material in order to reduce the L-direction warpage amount to a predetermined target value or less according to the output side tension, and an L-direction warp amount storage and arithmetic unit. The above problem is solved by applying a rolled material shape control device, characterized by having a rolled material angle adjustment control device that sets the rolled material pass angle to the means for adjusting the rolled material pass angle. ing.

Further, there is provided a rolled material shape control device having at least a means for adjusting the tension on the exit side of the rolling mill and a means for adjusting a pass angle of the rolled material on the exit side of the rolling mill, wherein the apparatus detects the rolling speed of the rolling mill. Rolling speed detecting means, a cross buckle storage calculating device for calculating an appropriate tension such that the cross buckle height becomes equal to or less than a predetermined target value according to the rolling speed detected by the rolling speed detecting means, A tension control device that outputs a tension to the control mechanism to control the tension, and a L that calculates an appropriate pass angle of the rolled material to reduce the amount of warpage in the L direction to a predetermined target value or less according to the tension output by the tension control device. It has a direction warpage amount storage arithmetic device, and a rolled material angle adjustment control device that sets the rolled material path angle calculated by the L direction warpage amount storage arithmetic device to the means for adjusting the rolled material pass angle. Solves the above problems by applying the shape control of the rolled material, characterized in that.

Here, it is preferable for the application of the present invention that the rolled material angle adjusting means is an anti-corrugated roll and the rolled material angle adjustment control device is an anti-corrugated roll position control device.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Based on various investigations and analysis in the operation of a temper rolling mill, the present inventors can adjust the change in the amount of cross buckle due to the change in rolling speed by controlling the output tension on the rolling mill. I found something. FIG. 2 illustrates this. FIG. 2 is a graph showing the relationship between the rolling mill exit side tension and the cross buckle height, and the rolling speed is 50 mp.
The graph shows two typical examples: a low speed at m and a high speed at a rolling speed of 1200 mpm.

When the target value of the cross buckle size is set, an appropriate rolling mill exit side tension at each rolling speed is determined based on the graph data of FIG. 2 so as to reach the set target value. It can be calculated. This makes it possible to set an appropriate rolling mill exit side tension that follows the rolling speed in the unsteady state of the temper rolling, and to keep the size of the cross buckle constant over the entire length of the rolled material. It was.

FIG. 5 is a graph showing the relationship between the rolling speed and the rolling mill exit side tension when the cross buckle height is set at a certain set target value. When the cross buckle height is to be constant over the entire length of the rolled material, it is sufficient to set the rolling mill exit side tension in accordance with the rolling speed based on FIG. Further, the present inventors have found that the amount of warpage in the L direction has a stable correspondence with the tension on the exit side of the rolling mill based on the same investigation and analysis. FIG. 3 shows a typical example.
The graph shows the relationship between the amount of warpage in the L direction and the tension on the exit side of the rolling mill when the rolling speed is 50 mpm.

As described above, the tension on the exit side of the rolling mill is adjusted to control the cross buckle, but this also changes the amount of warpage in the L direction. In the present invention, the control of the magnitude of the cross buckle and the adjustment of the L-direction warpage are performed at the same time, and the control of managing the L-direction warpage within the target value is also performed simultaneously. The control of the amount of warpage in the L direction is performed by lowering and rising the anticorrugated roll installed on the exit side of the rolling mill and adjusting the pass angle of the rolled material.

The rolled material pass angle refers to the angle of the rolled material with respect to a horizontal rolling line caused by the material being lowered and raised by an anticorrugated roll. It is known that the roll position of the anticorrugated roll and the amount of warpage in the L direction are proportional to each other when the rolling speed is constant. FIG. 4 is a graph showing the relationship at a rolling speed of 600 mpm as a representative example.

That is, the anti-corrugated roll is lowered and raised to change the height position relative to the roll of the final stand of the rolling mill, and the pass angle, which is the angle of the rolled material from the horizontal pass line with respect to the anti-corrugated roll, is increased or decreased. By doing so, the amount of warpage in the L direction can be controlled. Here, the anti-corrugated roll is lowered and raised in the direction of decreasing the pass angle of the anti-corrugate roll when the tension on the rolling mill exit side is increased, and in the direction of increasing the pass angle of the anti-corrugated roll when the tension on the rolling mill exit side is decreased. Let it do. Thus, the amount of warpage of the rolled material in the L direction can be controlled simultaneously with controlling the size of the cross buckle.

Next, a typical block configuration of a shape control device to which the present invention is applied will be described with reference to FIG. Rolled material 1
Is rolled by the temper rolling mill 2, and the output side tension is detected by the tension detector 8 on the output side of the rolling mill. Here, temper rolling mill 2
The rolling speed detector 3 is attached to one of the work rolls.

On the exit side of the tension detector 8, the pass angle of the rolled material 1 is adjusted by the anti-corrugating roll 11, and then, the tension control mechanism 7 applies the tension on the exit side of the rolling mill. The rolling speed detected by the rolling speed detector 3 is converted into a speed signal by a rolling speed signal converter 4 and input to a cross buckle storage arithmetic unit 5. 2 or 5 stored in advance in the cross buckle storage arithmetic unit 5.
Is calculated based on the relationship described above, and the tension value is taken into the tension control device 6 as an output signal. The tension control device 6 controls the tension control mechanism 7 based on the input tension value to adjust the necessary tension to the rolled material 1.
Is applied.

Here, in the cross buckle storage arithmetic unit 5, the tension value is calculated based on the cross buckle target value set by the cross buckle target value setting unit 10. On the other hand, the tension value detected by the tension detector 8 is
It is taken into the tension signal converter 9 and converted into a tension signal. The converted tension signal is sent to the cross buckle storage operation device 5 and the L-direction warp amount storage operation device 13, respectively, and is used as a reference signal for control. .

The L-direction warpage amount storage arithmetic unit 13 is based on the tension signal input from the tension signal converter 9 and the position signal of the anti-corrugated roll position detector 12 based on the relationship previously stored in FIG. Anti-corrugated roll 11
Is calculated, and the height position is sent to the anti-corrugating roll control device 14 as a control signal as described above.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG.
In the rolling speed pattern in the longitudinal direction of the rolled material as shown in (a), that is, in the pattern of the batch processing of the rolled material which is accelerated at the leading end of the rolled material, becomes a steady speed, and then is decelerated at the trailing end of the rolled material. The height of the cross buckle is shown in FIG.
As shown in the figure, it was possible to control to a constant value within the target range. At the same time, the amount of warpage in the L direction could be controlled to a constant value within the target range as shown in FIG.

On the other hand, FIG. 7 shows a case where this control is not performed, that is, a case where the tension is kept at a low level regardless of the speed. In the case of the rolling speed pattern shown in FIG. 7 (a), when the rolling speed falls below a certain speed,
As shown in FIG. 7B, the height of the cross buckle exceeds the target range. In this case, most of the L warpage is within the target range because the tension is stable while the tension is low.
However, when tension is applied to the cross buckle to control the cross buckle particularly at the unstable part where the rolling mill enters and exits, FIG.
As shown in (c), the L warpage increases accordingly (when the anti-corrugated roll position is constant).

[0028]

According to the present invention, it is possible to make the size of the cross buckle constant over the entire length of the rolled material. Further, by performing the cross buckle control, it becomes possible to simultaneously control the L-direction warpage, which tends to worsen, and it is also possible to suppress the L-direction warpage to a constant value over the entire length of the rolled material. Was.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a shape control device according to the present invention.

FIG. 2 is a graph showing a relationship between a rolling mill exit side tension and a cross buckle height.

FIG. 3 is a graph showing a relationship between a rolling mill exit side tension and an L-direction warpage amount.

FIG. 4 is a graph showing the relationship between the position of the anti-corrugated roll and the amount of warpage in the L direction.

FIG. 5 is a graph showing a relationship between a rolling speed and a rolling mill exit side tension.

FIG. 6 is a graph for explaining a control result in the present invention, in which (a) is a graph showing a rolling speed pattern from a rolling material entering a rolling mill to an exit thereof. (B) is a graph which shows the control result of the cross buckle height from the entrance of a rolling material to the exit of a rolling mill. (C) is a graph which shows the control result of the amount of L-direction warpage from the entrance of a rolling material to the exit of a rolling mill.

FIG. 7 is a graph for explaining a case where the present invention is not carried out, and FIG. 7 (a) is a graph showing a rolling speed pattern from entering a rolling mill to exiting a rolling material. (B) is a graph which shows the control result of the cross buckle height from the entrance of a rolling material to the exit of a rolling mill. (C) is a graph which shows the control result of the amount of L-direction warpage from the entrance of a rolling material to the exit of a rolling mill.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rolled material 2 Temper rolling mill 3 Rolling speed detector 4 Rolling speed signal converter 5 Cross buckle memory arithmetic unit 6 Tension controller 7 Tension control mechanism 8 Tension detector 9 Tension signal converter 10 Cross buckle target value setting unit 11 Anti-corrugated roll 12 Anti-corrugated roll position detector 13 L-direction warpage storage arithmetic unit 14 Anti-corrugated roll controller

Claims (8)

[Claims] 1. A method for controlling the shape of a rolled material, comprising adjusting a rolling mill exit side tension in accordance with a rolling speed. 2. A method for controlling a shape of a rolled material for controlling a rolling mill outlet side tension in accordance with a target cross buckle amount, wherein a relationship between the target cross buckle amount and the rolling mill outlet side tension is adjusted in accordance with a rolling speed. A method for controlling the shape of a rolled material, characterized in that: 3. A method for controlling the shape of a rolled material, comprising adjusting a pass angle of a rolled material on the roll-out side according to the roll-out side tension. 4. A rolled material characterized by adjusting a rolling mill outlet side tension in accordance with a rolling speed, and adjusting a pass angle of a rolled material on a rolling mill outlet side in accordance with the rolling mill outlet side tension. Shape control method. 5. A rolling material shape control device having at least a roll-side output tension adjusting means on the rolling mill outlet side, comprising: a rolling speed detecting means for detecting a rolling speed of the rolling mill; A cross buckle storage arithmetic unit that calculates an appropriate tension at which the cross buckle height is equal to or less than a predetermined target value according to the detected rolling speed, and a tension control device that outputs the calculated appropriate tension to a unit that controls the output side tension. And a shape control device for a rolled material. 6. A rolled material shape control device having at least a means for adjusting a pass angle of a rolled material at a rolling mill exit side, wherein the tension detector detects a rolling mill exit side tension; Rolling direction warpage amount storage / calculation device for calculating an appropriate rolled material pass angle in order to reduce the amount of warpage in the rolling direction to a predetermined target value or less according to the output side tension, and a warpage amount storage / calculation device for the rolling direction A rolled material angle adjustment control device that sets the rolled material pass angle calculated in the above step as a means for adjusting the rolled material pass angle. 7. A rolled material shape control device having at least means for adjusting a rolling mill outlet side tension and means for adjusting a rolled material pass angle on the rolling mill outlet side, wherein a rolling speed of the rolling mill is detected. Rolling speed detecting means, a cross buckle storage calculating device for calculating an appropriate tension at which the cross buckle height is equal to or less than a predetermined target value according to the rolling speed detected by the rolling speed detecting means; and A tension control device that controls the tension by outputting the output side tension to a means for adjusting the tension, and an appropriate rolled material to reduce the amount of warpage in the rolling direction to a predetermined target value or less according to the tension output by the tension control device. Rolling direction warp amount storage arithmetic unit for calculating pass angle, and rolled material angle for setting the rolled material pass angle calculated by the rolling direction warpage amount storage arithmetic unit to means for adjusting the rolled material pass angle Key An apparatus for controlling the shape of a rolled material, comprising: 8. The shape control of a rolled material according to claim 6, wherein the rolled material angle adjusting means is an anti-corrugated roll, and the rolled material angle adjustment control device is an anti-corrugated roll position control device. apparatus.