JPH067819A - Camber and meandering control method in rolling mill - Google Patents

Abstract

PURPOSE:To effectively suppress and control the camber and the meandering of a rolling material without necessitating complicated new device, etc., especially. CONSTITUTION:An outlet side plate wedge is predicted based on a detected value (the off-center amount) of a camber and meandering sensor 12 set up on the inlet side of the rolling mill 10. A roll wedge for sufficiently to eliminating the predicted plate wedge amount is then obtained based on the relation between the roll wedge and the outlet side plate wedge obtained in advance based on this predicted outlet side plate wedge amount and the work roll balancing force is controlled based on the roll wedge, by which the increase of the camber and meandering is suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling mill, and more particularly to a camber and meandering control method in a hot rolling mill.

[0002]

2. Description of the Related Art Conventionally, camber and meandering control in hot rolling have hardly been carried out in practice, and if it is said that the rolling conditions (for example, plate thickness, plate width, steel type, heating furnace conditions, etc.) are almost the same. There is only a method of applying the leveling performance value of the operator when rolling the material at the time of setting up the next material.

However, in this method, there are actually few materials under the same rolling conditions, and because of the actual values of the operator, there are many parts that depend on human senses, and reproducibility and reliability are poor. Even if the material is the same, it is considered that the roll wear, the temperature distribution in the width direction of the material, etc. are still different, and in many cases it is not always the same condition. Since it is a value at one point in the longitudinal direction of the material, it is difficult to say that it is effectively functioning due to reasons such as being unable to cope with changes over time in camber and meandering.

In view of the above point, as a technique for controlling camber and meandering in hot rolling, Japanese Unexamined Patent Application Publication No. S59-59
-229221, 62-54511, 62-686.
19th grade has been proposed.

In Japanese Patent Laid-Open No. 59-229221, first, the load difference between the driving side and the operating side of the outlet of the upstream stand and the off-center amount of the rolled material are detected, and from this detected value, the widthwise deformation resistance difference of the rolled material is obtained. It is shown that the plate wedge amount on the side is calculated, then the off-center amount is detected by the downstream stand, and the leveling correction of the downstream stand is performed from the detected value, the width direction deformation resistance difference, and the wedge amount on the exit side. There is.

Further, in Japanese Patent Laid-Open No. 62-54511, the camber of the rolled material generated by rolling in the rough rolling mill is corrected on the upstream side of the finishing rolling mill group, and the meandering of the rolled material is controlled by the finishing rolling mill group. A camber control method to perform is shown.

Further, in Japanese Patent Laid-Open No. 62-68619, a profile meter for measuring the strip thickness distribution is provided on the inlet side of the finish rolling mill, and the cross-sectional shape on the outlet side is predicted based on the measured value of the profile meter. A technique for adjusting the leveling, bender, roll shift, or reduction distribution of the finish rolling mill from this predicted value is shown.

[0008]

However, the technique proposed in Japanese Patent Laid-Open No. 59-229221 described above is based on the result of the upstream side, and sequentially controls and corrects it on the downstream side. Since a control error is added on the side, the control becomes complicated, and in reality, there is a problem that the control cannot be completed by the time it reaches the finish rolling mill, and a camber and a meandering amount may remain. Further, the method disclosed in Japanese Patent Laid-Open No. 62-54511 or 62-68619 has a problem that it is difficult to apply it to existing equipment because it requires complicated new equipment.

The present invention has been made in view of the above problems, and provides a camber and a meandering control method which are excellent in controllability and can be easily implemented by using an existing facility. Therefore, the above problems are not solved.

[0010]

As shown in the outline of the present invention, the present invention provides a procedure for detecting the camber and meandering amount of a material on the inlet side of a rolling mill, and the detected value on the outlet side of the rolling mill. A procedure of predicting the plate wedge amount, a procedure of obtaining a roll wedge amount sufficient to eliminate the predicted plate wedge amount, and a procedure of controlling the work roll balance force on the drive side and the operating side based on the roll wedge amount. By including it, the said subject was solved.

[0011]

In the present invention, the off-center amount of the plate is first determined by the camber and the meandering sensor installed on the inlet side of the rolling mill, and the plate wedge on the outlet side is predicted from this. Then, a roll wedge amount sufficient to eliminate the predicted plate wedge amount is obtained from this predicted plate wedge amount, and the work roll balance force on the drive side and the operation side is controlled based on this roll wedge amount. As a result, it is possible to effectively suppress the increase of camber and meandering in the rolling mill without changing the existing equipment.

[0012]

Embodiments of the present invention will now be described in detail with reference to the drawings.

First, as shown in FIG. 2, a sensor 12 for detecting the camber and meandering (off-center amount) of the rolled material 14 is installed on the entrance side of the rolling mill 10.

Next, the outgoing strip wedge of the rolling mill 10 is predicted from the camber and meandering value (off-center amount) measured by the sensor 12. The prediction of the plate wedge is performed by applying the measured value to the graph of off-center amount-plate wedge as shown in FIG. In the graph of FIG. 3, the relationship between the off-center amount and the outgoing side plate wedge is obtained in advance from the analysis result of the rolling simulation and the experimental result of the actual machine.

In this embodiment, in this way, the work side balance amount of the driving side and the operating side, which is sufficient (cannot generate), to predict the outgoing side plate wedge amount of the rolling mill and cancel the outgoing side plate wedge amount. And control so as to obtain this balance force. This balancing power is usually constant,
It can be controlled by making it transformable like a work roll vendor. The method of controlling the balance force is specifically based on the following ideas and methods.

(1) It can be considered that the mechanism in which the plate wedge is generated on the exit side of the rolling mill is that the roll is wedged as a result of the load difference between the driving side and the operating side caused by the camber and meandering. From this, it is possible to prevent the plate wedge by forcibly setting the roll wedge, which is the reverse of the plate wedge.

(2) Therefore, the method of determining the set amount of the roll wedge at this time becomes a problem, but as shown in FIG. 4, the relationship between the roll wedge and the outlet plate wedge can be known in advance. , Take advantage of this. Figure 4
Similar to FIG. 3, it is obtained by the rolling simulation analysis and the experimental result in the actual machine, and shows the transfer rate of the roll wedge. By using this FIG. 4, for example, when the predicted exit side wedge has a value of a and the roll wedge is set to the plate wedge and the operating side and the drive side is set to b in the opposite direction, the exit side plate wedge becomes zero. It will be.

(3) The difference between the work roll balance forces on the operating side and the driving side for specifically realizing the roll wedge amount determined by (2) is determined as follows. That is, the difference in balance force is generated by increasing the balance pressure in the direction in which the wedge is desired to be attached on the operating side or the driving side from the force due to the reference pressure. The relationship between the balance force difference and the roll wedge is shown in FIG. The relationship in FIG. 5 is also obtained from the rolling simulation analysis and the experimental result, as in FIGS. 3 and 4. If this relationship is used, if the roll wedge is known, the pressure increase value for causing the difference in balance force can be easily found.

If the above-mentioned operations are continuously carried out in the bar by using an online computer, it is possible to effectively suppress the change of the exit board wedge (without requiring a complicated new equipment). It becomes possible to prevent the increase of camber and meandering. To summarize the above operation,
It becomes like FIG.

FIG. 6 shows measured values of the off-center amount (camber, meandering amount) of the rolled material on the inlet side and the outlet side of the rolling mill when the present control method is applied to the actual rolling mill. In the figure,
The black dots indicate the measured values when this control method is not used, and the black dots surrounded by circles indicate the measured values when this control method is implemented. As is clear from the figure, when the present control method is not implemented, the larger the off-center amount on the input side, the greater the off-center amount on the output side accordingly. However, when rolling is performed after implementing this control method, even if the off-center amount on the inlet side is large, the off-center amount on the outlet side is stable at a very low value (not increasing).
I understand. In this way, it was confirmed that the present control method was very effective by the investigation using the actual machine.

[0021]

As described above, according to the present invention, the camber and meandering of the rolled material can be ensured easily and at low cost by a slight improvement of the current rolling mill without requiring complicated new equipment. The excellent effect of being able to suppress it is obtained.

[Brief description of drawings]

FIG. 1 is a flow chart showing the gist of the present invention.

FIG. 2 is a diagram showing an installation relationship between a rolling mill and a meandering sensor.

FIG. 3 is a diagram showing the relationship between the amount of meandering and the outlet plate wedge.

FIG. 4 is a diagram showing the relationship between the roll wedge and the outlet plate wedge.

FIG. 5 is a diagram showing the relationship between the difference between the work roll balance force on the driving side and the operating side and the roll wedge.

FIG. 6 shows a case where this control method is applied and a case where this control method is not applied.
A diagram showing the relationship between the input off-center amount and the output off-center amount for comparison

[Explanation of symbols]

 10 ... Rolling machine 12 ... Meandering sensor 14 ... Rolling material (rolled material)

Claims (1)

[Claims] 1. A procedure for detecting a material camber and a meandering amount on the inlet side of a rolling mill, a procedure for predicting a sheet wedge amount on the outlet side of the rolling mill from the detected values, and a method for canceling the estimated sheet wedge amount. A method for controlling a camber and meandering in a rolling mill, comprising: a procedure for obtaining a sufficient roll wedge amount; and a procedure for controlling a work roll balance force on a driving side and an operating side based on the roll wedge amount.