JP2719212B2 - Strip shape and strip crown control method in strip rolling - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a sheet shape and a sheet crown in rolling a steel sheet or other metal sheets.

[Prior Art] One of the qualities of a steel plate or a rolled metal plate used for a vehicle, a home electric appliance or the like is a plate shape, a plate crown and an edge drop.

Recently, the demands of users for plate shapes and the like have become more severe, and therefore, various rolling methods or rolling mills capable of controlling the plate shape, plate crown or edge drop have been developed. For example, a six-high rolling mill equipped with an intermediate roll shift mechanism and a work roll bender, a rolling mill in which upper and lower work rolls are crossed, and a six- or twelve-high cluster rolling in which a backup roll is divided into a plurality along the roll axis direction Mills and rolling mills that give offset and horizontal deflection to small-diameter work rolls (see "Japan Plastic Working II", Japan Plastic Working Association, August 14, 1986).
Further, the rolling mill disclosed in JP-A-60-238005,
There is provided a bading device for bearing-supporting the work roll by the inner shaft box and the outer shaft box, and applying horizontal bending to the outer shaft box with the inner shaft box as a fulcrum.

All of these rolling mills attempt to elastically deform a work roll into a required shape by a roll bending force or a roll shift to obtain a desired plate shape, plate crown or edge drop.

[Problems to be Solved by the Invention] During the rolling, the thermal crown of the work roll fluctuates, the crown of the plate supplied to the rolling mill fluctuates, and the shape of the rolled plate and the plate crown sometimes change. It fluctuates every moment. In order to prevent these fluctuations, a shape control means such as the horizontal roll bender or the vertical roll bender is used. However, these shape control means have insufficient control accuracy in order to obtain a highly-accurate plate shape or plate crown which has been particularly required recently.

Therefore, an object of the present invention is to provide a plate shape / plate crown control method capable of controlling a plate shape and a plate crown with high accuracy.

[Means for Solving the Problems] The sheet shape / sheet crown control method in sheet rolling according to the present invention provides a sheet shape or sheet crown by applying a horizontal roll bending force to at least one roll offset in the horizontal direction. In the sheet rolling for controlling the roll width, at least one of the sheet shape and the sheet crown is detected on the exit side of the rolling mill, and the horizontal roll bending force and the roll offset amount of the roll are controlled based on the detection result.

In the case of cold rolling, only the plate shape is controlled. Therefore, the sheet crown is not detected. In the case of hot rolling, at least one of the sheet shape and the sheet crown is controlled.
In any case, the relationship between the plate shape and the plate crown and the operation amount of each control operation end is previously created as an operation model formula by a rolling experiment or numerical calculation, and saved as an operation table in a control computer or the like. deep.
At the time of rolling, the operation amount of each control operation end is obtained from the detected value of the plate shape and the plate crown and the operation model formula, and each control operation end is controlled accordingly. The control operation end is the horizontal roll bender and the roll offset amount adjusting device, and another control operation end may be used. Other control operation ends include, for example, a vertical roll bender of an intermediate roll and a work roll in the case of a six-roll mill, and a vertical roll bender of a work roll in the case of a quadruple rolling mill. Also, the horizontal roll bender and the roll offset adjusting device may be provided on one of the work rolls or the intermediate roll,
It is preferable to provide both two work rolls or two intermediate rolls.

As the horizontal roll bender, for example, a known roll bender that applies a bending force by a hydraulic cylinder connected to a roll shaft is used. As the roll offset adjusting device, for example, a device including a wedge slidably inserted between a housing and a bearing box and a hydraulic cylinder for inserting and removing the wedge is used. The roll offset adjusting device can adjust the roll offset amount even during rolling. When the intermediate roll is provided with a horizontal roll bender and a roll offset adjusting device, it is desirable to provide the intermediate roll with a convex crown having a roll radius of about 0.05 to 0.3 mm. Further, it is preferable that the roll shaft is supported by a self-aligning bearing so that the roll shaft can be freely deformed when a bending force is applied.

As described above, the present invention controls the horizontal roll bending force and the roll offset amount as control of the plate shape or crown, but further controls the vertical roll bending force for at least one of the intermediate roll and the work roll. You may make it. In this case, the control range of the plate shape or the plate crown can be further expanded.

[Operation] Since both the horizontal bending force of the roll and the roll offset amount are adjusted, the shape of the work roll can be changed in a wide range. In addition, since the sheet shape or the sheet crown is detected on the exit side of the rolling mill, and the horizontal bending force and the roll offset amount of the roll are controlled based on the detection result, a highly accurate sheet shape or sheet crown can be obtained. .

[Embodiment] FIGS. 1 and 2 show an embodiment of the present invention. FIG. 1 is a side view of a six-layer rolling mill including a block diagram of a control system, and FIG. It is a top view of the roll which has a horizontal roll bender and a roll offset adjustment apparatus, and its bearing box.

The upper and lower work rolls 3 are provided with bearing housings 4 at the roll shafts.
It is supported by. The hydraulic cylinder 6 of the vertical roll bender 5 is connected to the bearing housing 4. The vertical roll bender 5 applies a vertical bending force to the work roll 3.

The intermediate roll 7 is supported by a bearing housing 11. Bearing housing 11
Is a self-aligning bearing comprising a convex spherical inner ring 12 and a concave spherical seat 13. By supporting the roll shaft portion 8 with the self-aligning bearing, when a bending force is applied to the intermediate roll 7, the roll shaft portion 8 is freely deformed and concentration of stress is avoided. A hydraulic cylinder 16 of a horizontal roll bender 15 is connected to a portion of the intermediate roll 7 near the shaft end of the roll shaft portion 8. Also, a bearing box of the housing 1 and the intermediate roll 7
The wedge 19 of the roll offset adjusting device 18 is slidably inserted between the roll offset adjusting device 18 and the hydraulic cylinder 20 of the roll offset adjusting device 18. The hydraulic cylinders 20 work together so that when one wedge 19 moves forward, the other wedge 19 moves backward by the same distance. Also, the bearing box of the intermediate roll 7
The hydraulic cylinder 23 of the vertical roll bender 22 is connected to 11. The intermediate roll 7 is supported by a backup roll 9.

The control device 25 includes a shape detector 26 disposed on the exit side of the rolling mill.
And a sheet crown detector 27. Shape detector 26
Consists of a split roll type shape detector and a plate crown detector
27 is a mobile X-ray thickness gauge. Signals from the shape detector 26 and the sheet crown detector 27 are output to a signal processing circuit 29.
Are amplified and A / D-converted, and input to the control operation circuit 31. A target value is input to the control operation circuit 31 from the setting circuit 32 in advance and is set. Control operation circuit
In response to the signal from 31, the controller 34 outputs operation signals to the vertical roll bender 5 of the work roll 3, the horizontal roll bender 15 of the intermediate roll 7, the roll offset adjusting device 18 and the vertical roll bender 22.

In the six-high rolling mill configured as described above, the magnitude of the vertical bending force acting on the work roll 3, the magnitude of the horizontal and vertical bending forces acting on the intermediate roll 7, the roll offset amount, the plate shape, the plate The relationship between the crown and the edge drop amount is experimentally obtained for the actual machine in advance, and is stored in the control arithmetic circuit 31 as an arithmetic table.

At the start of rolling, when the sheet size, rolling amount and other rolling conditions, the target sheet shape and the sheet crown are input to the control arithmetic circuit 31, the work roll 3 becomes perpendicular bending force and the intermediate roll 7 becomes convex toward the rolling mill exit side. The curving horizontal roll bending force and vertical bending force and the offset amount on the rolling mill exit side are set. In addition, the rolling performance data of the previous coil is used for learning of the setting model.

When the rolling is started, the strip shape and the strip crown of the strip rolled on the exit side of the rolling mill are detected. Based on the detection result, the vertical bending force of the work roll 3, the horizontal and vertical bending forces of the intermediate roll 7, and the roll offset amount are adjusted, and the plate shape and the plate crown are feedback-controlled.

3 and 4 show another embodiment of the present invention. FIG. 3 is a side view of a quadruple rolling mill including a block diagram of a control system, and FIG. 4 is a horizontal roll bender and roll offset. It is a top view of the roll which has an adjustment device, and its bearing box. Devices and members similar to those shown in FIGS. 1 and 2 are denoted by the same reference numerals, and description thereof will be omitted.

The upper and lower work rolls 3 are supported by the self-aligning difficult bearing box 11 at the roll shaft portion 5. A hydraulic cylinder 16 of a horizontal roll bender 15 is connected to the work roll 3 near the shaft end of the roll shaft 5. A wedge of a roll offset adjusting device 18 is provided between the housing 1 and the bearing housing 11.
19 is slidably inserted. A wedge 19 is slidably inserted. A hydraulic cylinder 20 is connected to an end of the wedge 19. Further, the hydraulic cylinder 6 of the horizontal roll bender 5 is connected to the bearing housing 11.
The hydraulic cylinders 6, 16, and 20 are all controllers 34
The operation is controlled by.

The operation of the quadruple rolling mill configured as described above is the same as that of the above-described six-high rolling mill except for controlling the shape of the intermediate roll.

Here, a specific example in which a steel sheet is rolled by the six-layer rolling mill will be described.

Rolling machine configuration Work roll: Roll diameter 550mm, Roll trunk length 1820mm Intermediate roll: Roll diameter 400mm, Roll trunk length 1820mm Roll offset amount 0-40mm, Horizontal bending force ± 40TON Roll crown 0.16mm radiation crown Backup roll: Roll diameter 1420mm , Roll body length 1820mm Rolled plate Material: ordinary steel Plate thickness: 2.7mm → 0.6mm Plate width: 1500mm Rolling conditions Rolling rate: 30% Rolling speed: 1500m / min In the above cold rolling, the vertical belting force of the work roll, The horizontal and vertical bending force of the intermediate roll and the roll offset amount were controlled. As a result, the plate shape could be controlled within a plate steepness of 0.5% or less, and a steel plate having a good plate shape and a good sheet crown could be rolled.

[Effects of the Invention] According to the present invention, a sheet shape or a sheet crown is detected on the exit side of a rolling mill, and both the horizontal bending force and the roll offset amount of the roll are controlled based on the detection result. Plate shape and plate crown can be obtained.

[Brief description of the drawings]

FIG. 1 and FIG. 2 show an embodiment of the present invention.
FIG. 1 is a side view of a six-type rolling mill including a block diagram of a control system, FIG. 2 is a plan view of a roll having a horizontal roll bender and a roll offset adjusting device of the above-described rolling mill, and a bearing box thereof, and FIG. FIGS. 4A and 4B show another embodiment of the present invention. FIG. 3 includes a block diagram of a control system.
FIG. 4 is a side view of the heavy rolling mill, and FIG. 4 is a plan view of a roll having a horizontal roll bender and a roll offset adjusting device of the rolling mill of FIG. 3 and a bearing box thereof. DESCRIPTION OF SYMBOLS 1 ... Housing, 3 ... Work roll, 5 ... Vertical roll bender, 6 ... Hydraulic cylinder, 7 ... Intermediate roll, 9 ... Backup roll, 11 ... Bearing box, 15 ...
Horizontal roll bender, 16 hydraulic cylinder, 18 roll offset adjustment device, 19 wedge, 20 hydraulic cylinder, 22 vertical roll bender, 23 hydraulic cylinder, 25 control device, 26 … Shape detector, 27 ……
Plate crown detector, 29 ... signal processing circuit, 31 ... control arithmetic circuit, 32 ... setting circuit, 34 ... controller.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Matsuo Ataka 1-1-1 Edamitsu, Yawatahigashi-ku, Kitakyushu-shi, Fukuoka Nippon Steel Corporation 3rd Technical Research Institute (56) References JP-A-58-116916 (JP, A) JP-A-61-103610 (JP, A) JP-A-62-238014 (JP, A)

Claims (1)

(57) [Claims] In a sheet rolling for controlling a sheet shape or a sheet crown by applying a horizontal roll bending force to at least one roll which is offset in the horizontal direction, the sheet shape and the sheet crown are selected on the exit side of the rolling mill. And controlling the horizontal roll bending force and the roll offset amount based on the detection result.