JPH01313107A - Method for centering rolled stock in reversible rolling - Google Patents

Abstract

PURPOSE:To perform centering operation without reatriction of a rolled stock and to also perform stable operation by moving side guides to be closed by motors after completion of horizontal rolling, stopping the closing motion after the motors act for a set period of time by electric currents exceeding a set value, and performing open motion of the guides up to a set opening value. CONSTITUTION:At the time when a rolled stock 3 is subjected to horizontal rolling by a horizontal roll 2 and a rolling load detector 10 detects rolling completion, driving motors M1,M2 are actuated by a motor controller 9 and side guides 4 start closing motion. At the time, actual electric current values 15 of the motors M1, Md2 are compared with a set standard electric current value 11. A period of time for which the currents 15 are larger than the current value 11 is measured by a timer 8 and a closing motion finish signal 13 of the side guides 4 is sent to the controller 9 to stop the closing motion when the period reaches a set period of time 12. Further, a position of the guides 4 is detected by a position detector 19, a position detection signal 20 is sent to the controller 9 to perform opening motion of the guides 4 up to a set opening value.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for centering a rolled material in reversible rolling.

<Prior art> In horizontal rolling, rolling is not completed due to various factors such as non-uniformity in thickness and material quality in the width direction of the rolled material, improper setting of the rolling opening of the rolling rolls, etc., as shown in Fig. 4. A so-called off-center condition may occur in which the center line 21 of the subsequent rolled material 3 is not aligned with the rolling line direction 22 but is inclined. In addition, in the figure, 1 is a vertical rolling roll, and 2 is a horizontal rolling roll.

If the next pass rolling is performed without correcting this off-center, camber (lateral bending) will occur in the rolled material after rolling. Further, when a horizontal rolling mill has vertical rolling rolls on the entry side, the rolled material may hit the vertical rolling rolls, making it impossible to continue rolling or causing scratches on the vertical rolling rolls.

In order to solve this problem, conventionally, for example, Japanese Patent Laid-Open No. 61-2
22626, a method of measuring the meandering amount of the rolled material using an image sensor and individually operating a plurality of cylinders installed in the direction of the rolling line to control the position of the rolled material and centering the rolled material. , JP-A-61-21
As in Japanese Patent No. 2418, a method has been proposed in which the rolled material is fed into the horizontal rolling mill while being centered by a vertical rolling mill on the entry side of the horizontal rolling mill.

<Problems to be Solved by the Invention> However, the centering method disclosed in Japanese Patent Laid-Open No. 61-222626 requires an image sensor and also has a complicated configuration because multiple cylinders must be controlled individually. There is a problem with becoming.

Furthermore, the centering method disclosed in Japanese Patent Application Laid-Open No. 61-212418 has the problem that it cannot be implemented in a horizontal rolling mill that does not have a vertical rolling mill.

An object of the present invention is to provide a method for centering a rolled material in reversible rolling that eliminates the above-mentioned problems.

<i! ! Means for Solving the Problem> The first invention is a method for centering a rolled material in a reversible rolling mill equipped with front and rear side guides, after detecting the end of horizontal rolling with a rolling load detector, Drive the drive motor to close the side guide,
The fruit of the said drive motor! After the state in which the lt current value is greater than or equal to the preset current value continues for a preset time, the closing operation is stopped, and the side guide is then opened by a preset opening degree that is greater than the opening degree of the side guide at that time. It operates by opening.

The second invention is a method for centering a rolled material in a reversible rolling mill equipped with front and rear side guides, in which a rolling load detector detects the end of horizontal rolling, and then the side guide drive motor is driven to center the rolled material. If the guide is closed and the actual current value of the drive motor continues to be greater than or equal to the preset current value for a preset time, the closing operation is stopped and the side guide at that point is then opened. The side guide is opened by a preset opening degree, or is the actual performance of the drive motor? If the rolling load detector detects the start of the next bus rolling before the f@ value continues to be equal to or higher than the preset current value for a preset time, at that point the side guide The closing operation is stopped, and then the side guide is opened by a preset opening degree than the opening degree of the side guide at that time.

Effects> The judgment as to whether or not the side guide is actually centering the rolled material is based on the fact that the actual current value of the side guide drive motor when the rolled material is being centered by the side guide is greatly affected by the load. Since the current value increases, it can be determined based on the actual current value. That is, the actual current value is compared with a preset reference current value, and if the actual current value is larger than the reference current value, it can be determined that centering is in progress, and if not, it can be determined that centering is not in progress.

In addition, in order to prevent the rolled material from being restrained by the side guides, the time during which the actual current value is greater than the reference current value is the time during centering, so this time is measured and set in advance. When the time has elapsed, the centering of the rolled material, that is, the closing operation of the side guides, may be stopped, and then the site guides may be opened by a preset opening degree that is greater than the opening degree of the side guides at that time.

<Example> An embodiment of the present invention will be described based on the drawings.

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

In the figure, 4.5 is a side guide, M+ and Mt are drive motors for the side guide 4, and M3°M is a drive motor for the side guide 5. In addition, the drive motor M, ~
The configuration of the control system of M4 is the same as that of drive motor M+, so
It is omitted in the figure.

2 is a horizontal roll of a reversible rolling mill. When the rolled material 3 advances in the direction of the arrow 17 and is horizontally rolled by the horizontal rolls 2, and the rolling load detector 10 detects that the horizontal rolling is completed, the motor control device 9
The drive motors M, , M are driven, and the side guide 4 starts its closing operation.

Here, it is determined whether or not the side guide 4 is actually centering the rolled material 3.
Drive motor M+, M when centering by
Since the actual current value 15 at t increases greatly depending on the load, it can be determined based on the actual current value 15.

That is, the actual current value 15 is compared with a preset reference current value 11, and if the actual current value 15 is larger than the reference current value 11, it is determined that centering is in progress; otherwise, it is determined that centering is not in progress.

Next, if the closing operation of the side guide 4 is continued and centering is continued, the side guide 4 will eventually restrain the rolled material 1 and rolling will not be possible. It is necessary to stop the closing operation.

In order to prevent the rolled material 3 from being restrained by the side guides 4, it is sufficient to limit the centering execution time.
The actual current value 15 is the reference current value! ! The timer 8 measures the time during which the value is greater than , and the preset time 12
When this point is reached, a signal 13 instructing the centering of the rolled material 3, that is, the end of the closing operation of the side guides 4, is sent to the motor control device 9, and the closing operation of the side guides 4 is completed and stopped.

However, at this time, if only the closing operation of the side guide 4 is ended and stopped, the rolled material 3 may remain restrained by the side guide 4 as shown in FIG. 1)), in order to prevent this, after the closing operation of the side guide 4 is finished and stopped, the side guide position detector 19 detects the position of the side guide 4, and the side guide position detection signal 20 is sent to the control device. 9, and the side guide 4 is opened to a wider opening by a preset opening d (see FIG. 2 (2)).

By the method described above, it becomes possible to perform centering without restraining the rolled material 3, and the next pass rolling in the direction of the arrow 18 can be performed stably.

In the actual rolling operation, as shown in FIG. 3, the next pass rolling of the rolled material 3 may occasionally be started before the centering is completed. In such a case, even if the side guide 4 is forced to perform a centering operation, the restraining force of the horizontal rolling roll 2 on the rolled material 3 is greater, so centering cannot be performed, and the drive motor M1. Mt wastes power. To avoid this, if the rolling load detector IO detects the start of next pass rolling during centering operation,
It is preferable to stop the closing operation of the side guide 4, open the side guide 4 to a preset opening degree 2 wider than the current opening degree, and complete the centering of the side guide. be.

Although the above description has been made regarding the side guide 4, the same applies to the side guide 5.

Next, a more specific example will be described.

In a reversible rolling mill of a hot rolling line, the reference current value is 11.
be equal to the rated current value of side guide motors M, ~M4, timer setting time 12 is 2 seconds, setting opening degree d is 50 degrees,
When the method of the present invention was carried out with the set opening degree 2 set to 50 m, it was confirmed that centering of the rolled material 3 could be performed without being restrained by the side guides 4.5, making it possible to realize stable rolling operations. Ta. Note that, as a matter of course, each of the above set values may be arbitrarily set according to the characteristics of the rolling equipment.

<Effects of the Invention> As explained above, the present invention can perform reversible rolling without using a vertical rolling mill or complicated control means as in the prior art.
The rolled material can be accurately centered by a simple means, and excellent effects such as stable rolling operation and prevention of roll flaws are achieved.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of an embodiment of the present invention, and FIG.
FIG. 3 is an explanatory diagram of the operation of the side guide shown in FIG. 3, FIG. 3 is an explanatory diagram showing the restraint state of the rolled material by the horizontal rolling rolls of FIG. 1, and FIG. 4 is an explanatory diagram of the off-center state of the rolled material. DESCRIPTION OF SYMBOLS 1... Vertical rolling roll, 2... Horizontal roll of reversible rolling mill, 3... Rolled material, 4.5... Side guide, M1 to M4... Drive motor for side guide, 6・・・
・Drive motor current detector, 7... Comparator, 8... Timer, 9...
Drive motor control device, 10... Rolling load detector, 11... Current reference value, 1
2...Timer setting time, 13...Signal to notify completion of centering, 14...
Rolling load detection signal, 15... Actual motor current value, I6... Signal indicating that centering is in progress, 1
9... Side guide position detector, 20... Side guide position detection signal. Patent applicant Kawasaki Steel Corporation Figure 1 Figure 2 Figure 3 Figure 4

Claims (2)

[Claims] (1) In a method for centering rolled material in a reversible rolling mill equipped with front and rear side guides, a rolling load detector detects the end of horizontal rolling, and then the side guide drive motor is driven to close the side guides. Then, after a state in which the actual current value of the drive motor is equal to or higher than a preset current value continues for a preset time, the closing operation is stopped, and then the opening degree of the side guide at that time is set in advance. A method for centering a rolled material in reversible rolling, characterized by opening a side guide by an opening degree. (2) In a method for centering rolled material in a reversible rolling mill equipped with front and rear side guides, a rolling load detector detects the end of horizontal rolling, and then the side guide drive motor is driven to close the side guide. However, if the actual current value of the drive motor continues to be greater than or equal to the preset current value for a preset time, the closing operation is stopped, and then the opening degree of the side guide at that point is When the side guide is opened by the set opening degree, or before the actual current value of the drive motor continues for a preset time, the rolling load detector detects the next pass. When the start of rolling is detected, the closing operation of the side guide is stopped at that point, and then the side guide is opened by a preset opening degree than the opening degree of the side guide at that time. A method for centering rolled material in reversible rolling.