JPH08155518A - Rolling method for sheet - Google Patents

Abstract

PURPOSE: To prevent camber in a rolling stock by making the quantity of horizontal deflection or horizontal support differentiated between an upper and a lower work roll, on the basis of the estimated position of the vertical displacement of the upper and lower work roll. CONSTITUTION: A rolling load outputted by a load cell 21, output signal from a thickness gauge 29, displacement outputted by a displacement gauge 28 for reduction cylinder, etc., are inputted in a passline variation compensator 30 for the variation of the passline to be computed. The signal of the passline variation is inputted in a device 24 for setting a horizontal cylinder position; the correction value of the upper and lower horizontal cylinders is calculated, with the control quantity for each upper and lower horizontal position differentiated for the correction value corresponding to the passline variation; and the instruction is given to servo valves 17-i, 18-i. Rolling is possible with a horizontal relative position maintained between the upper and lower work rolls, thereby preventing the camber of the rolling stock.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling method in which upper and lower small-diameter work rolls are controlled so as to be bent horizontally in a horizontal direction or at a position slightly deviated from the horizontal in a vertical direction, or are supported in a horizontal position. It is a thing.

[0002]

2. Description of the Related Art In recent years, the shape of a rolling mill in the sheet width direction has been finely and accurately corrected, and a material having a higher deformation resistance than that of a conventional material is rolled at a reduction rate substantially equal to that of the conventional material. For this purpose, the upper and lower backing rolls 5, 6, 7, 8 as a 6Hi rolling mill, or the work rolls 3, 4 supported by 5, 6 as a 4Hi rolling mill have a small diameter of 400 mm or less within the allowable range of strength. A rolling device having a work roll horizontal direction supporting device for supporting the upper and lower work rolls 3 and 4 to which a rolling load is applied in a horizontal direction or a position slightly deviated from the horizontal direction in at least the same direction as the rolling direction is provided. Being developed. The plate rolling apparatus is shown in FIG.
6A and 6B (FIG. 6B shows B- of FIG. 6A).
(It is a detailed view of 4, 10, 12, 14 cross section as seen from the arrow B.) As illustrated, the work rolls 3 and 4 that are vertically opposed to the rolling mill 1 and roll down the rolled material 2 from above and below are substantially horizontal. By supporting the work rolls 3 and 4 from the horizontal direction, the work rolls 3 and 4 are prevented from being disturbed by the horizontal deflection, and in addition to the function of rolling, the work rolls 3 and 4 are positively applied with a pushing force from a substantially horizontal direction. As a result, the horizontal restraining rolls 11 and 12 that generate the bending force of the work roll chock that supports the work rolls 3 and 4 in the horizontal direction are divided into n, and the divided i
Second roll 11-i and 11-i + 1 and 12-i and 12-i + 1
The hydraulic cylinders 13-i and 14-i embedded in the housing distribute the horizontal pushing force to the shaft portion and / or the roll end shaft between the work rolls 3 and 4 with a high degree of freedom. The horizontal bending is generated, and the horizontal bending having a high degree of freedom is converted into the bending in the plate thickness direction having a high degree of freedom along the vertical restraining rolls 7 and 8 so that the shape of the rolled material 2 is controlled. It also has a function of controlling the shape of No. 2. In the example of the rolling device 1, if the work rolls 3 and 4 are bent in the horizontal direction, the center of the roll gap between the upper and lower work rolls 3 and 4 is narrowed with respect to the roll ends, and the shape of the rolled material 2 is set to the middle. If the work rolls 3 and 4 are bent to the horizontal entering side, the roll gap between the upper and lower work rolls 3 and 4 is narrowed at the roll end with respect to the center, and the shape of the rolled material 2 can be changed. Can be changed in the direction of the ear wave.

In such a rolling device 1, the strength of the work roll neck portion and the work roll chocks 31 (upper side not shown) and 41 for horizontally supporting the work rolls 3 and 4 are provided.
The allowable limit load of horizontal bending is limited by the radial bearing strength, and the work rolls 3 and 4 have a small diameter. Therefore, this allowable limit load is much lower than that of a normal large-diameter rolling mill. It is about 10 tons). Therefore, when the horizontal bending forces applied to the upper and lower work roll chocks 31 and 41 are different, the horizontal bending allowable limit load is likely to be reached by the difference between the upper and lower bending forces, so that the horizontal bending control range is narrowed. FIG. 7 shows a case in which the bending force is applied only to the center position of the upper work roll chock 31 and the bending force is further applied to or subtracted from the upper and lower work rolls 3 and 4. When the work roll 3 reduces the bending force, the lower work roll 4 reaches the allowable limit load first, and the target bending force cannot be applied to the other work roll that has not reached the allowable limit load. Since the strength of the equipment is dangerous, the usable range of bending force is narrower than the original range of bending force available. Further, when the rolling device 1 does not positively use the horizontal bending of the work rolls 3 and 4 for shape control and simply supports the work rolls 3 and 4 from the horizontal direction, for example, an initial setting failure, a rolling position described below. Even when the pass line changes due to, the bending forces of different magnitudes may be generated in the upper and lower work rolls 3 and 4, respectively. If the horizontal bending forces of the upper and lower work rolls 3 and 4 are different, the horizontal deflection of the upper and lower work rolls 3 and 4 is different, and the work rolls 3 and 4 are in a state of being offset in the rolling direction. Lateral rigidity changes and shape control becomes difficult, and problems such as warpage of the rolled material 2 occur. In order to eliminate such a problem, the horizontal pushing cylinder 13-0 so that the horizontal bending forces applied to the upper and lower work roll chocks 31, 41 become equal.
~ 13-n, 14-0 to 14-n must be set. In the conventional rolling mill, (1) the amount of movement of the upper and lower horizontal support devices from the reference position setting such as zero adjustment is equal. To do. (2) Make the pushing force of the upper and lower horizontal supports equal. The horizontal support device is set like this.

[0004]

Usually, the rolling hydraulic cylinder of the rolling mill is attached to either the lower part or the upper part of the rolling mill. Change occurs. For example, when the hydraulic cylinder for rolling down is located at the lower part of the rolling mill, if the hydraulic cylinder is pushed up to increase the load, the pass line rises and the work rolls 3 and 4 are temporarily offset. Therefore, if the upper work roll 3 is bent toward the exit side and the lower work roll 4 is bent toward the entrance side, the upper pushing force is increased by an amount corresponding to the bending force required to bend the upper work roll 3, so that the upper pushing force is increased. There is a difference in the pushing force up and down in the direction of increasing. That is, the pushing force on the upper side is increased by the amount of bending force required to bend the upper work roll to the exit side, and the bending force required to bend the lower work roll to the entry side is generated on the entry side in the rolling direction. The pushing force on the lower side becomes smaller as much as it is made. Not only that, the horizontal force between the work rolls acts in a direction in which the offset between the work rolls 3 and 4 is increased (the upper work roll 3 is on the outgoing side and the lower work roll 4 is on the incoming side). Further, the reaction force from the pressing rolls 5 and 6 also acts so that the upper side becomes smaller and the lower side becomes larger as the offset of the upper work roll 3 becomes smaller. Due to these forces, a vertical difference occurs in the pushing force in the direction in which the upper pushing force is reduced and the lower pushing force is increased. There is a characteristic that.

As a result, as shown in FIG. 8, the above-mentioned force acts in the direction of increasing the upward pushing force, but the above-mentioned force acts in the direction of decreasing the upward pushing force. Further, although the vertical difference of the pushing force generated by does not depend on the value of the rolling load at that time, the vertical difference of the pushing force due to changes by the rolling load. Therefore, there is a singular point rolling load in which the effect of the pushing force due to and is just balanced and the vertical pushing force does not change even if any offset between the work rolls 3 and 4 occurs. When an offset occurs between the work rolls 3 and 4, if the load is lower than the singular point load, the pushing force on the upper side becomes large, and if the load is high, the pushing force on the lower side becomes large. Further, if the work rolls 3 and 4 have a small diameter,
Since the work rolls 3 and 4 are easily bent, the vertical difference in the horizontal bending force of the work rolls, and hence the vertical difference in the horizontal pushing force, which are generated by the above-mentioned effects, are relatively small values. On the contrary, the horizontal force between the work rolls is Since it increases in inverse proportion to the roll diameter, it becomes a relatively large value in a small diameter work roll rolling device.Therefore, in the rolling device for a small diameter work roll, the singular point load described above exists within the rollable load range of the rolling device. To do. Therefore, the above horizontal push cylinder setting method has the following problems.・ If the upper and lower horizontal pushing forces are set equal, the pushing force on the side with the larger pushing force is reduced, that is, the pushing force on the side with the smaller pushing force is increased in the pulling direction of the horizontal support device. The horizontal supporting device acts in the direction of pressing, that is, in the pushing direction of the horizontal supporting device. However, when the rolling load is equal to or more than the above singular point (S point) load, the effect of is larger, so that the work roll 3 changes due to the change of the pass line. Even if an offset is temporarily generated between No. 4 and No. 4, the downward pressing force becomes large. for that reason,
Since the horizontal support device acts not in the direction of converging the offset between the work rolls 3 and 4 but in the direction of expansion,
On the contrary, there was a problem that the offset between the work rolls 3 and 4 was increased.

FIG. 9 shows a rolling apparatus 1, which includes work rolls 3 and 4
It shows the change in the vertical difference of the horizontal pushing force generated when there is an offset between them due to the load. When the horizontal support device is set so that the upper and lower horizontal pushing forces are equal, the upper pushing force becomes larger than the lower pushing force at a load of point S or less, so that the upper work roll 3 is placed on the entry side and the lower work is set. The horizontal support device acts so as to displace the roll 4 to the exit side, and the offset between the work rolls 3 and 4 can be eliminated.
The offset between the work rolls 3 and 4 cannot be eliminated because it is a singular point at which a vertical difference in pushing force does not occur even if there is an offset between the work rolls 3. Therefore, the upper and lower work rolls 3
It is impossible to set the values of the horizontal bending forces of the same. Further, even if the upper work roll 3 is on the exit side under a load of the point S or higher, the downward pressing force is large, so the upper work roll 3
The work rolls 3, 4 because the horizontal support device acts so as to displace the lower work roll 4 toward the entrance side.
The offset increases, and eventually rolling becomes impossible.
Therefore, it is understood that it is impossible to prevent the offset between the work rolls 3 and 4 by the control in which the vertical pressing forces are equal. If the upper and lower horizontal support device movement amounts are set equal, the upper and lower horizontal support device positions are the same regardless of the movement of the pass line.
Is displaced to the outgoing side along the upper split roll 10-i, and the lower work roll 4 is displaced to the incoming side along the lower split roll 11-i. That is, the upper work roll 3 bends toward the rolling direction outlet side and the lower work roll 4 deflects toward the rolling direction inlet side, so that an offset between the work rolls remains. The thick line in FIG. 9 is an example of measuring the vertical difference of the horizontal pushing force. The pass line rises as the load increases, and the offset between the work rolls 3 and 4 increases. Therefore, the vertical difference of the pressing force changes on a curve in which there is a different offset between the work rolls 3 and 4 depending on the rolling load, as shown by the thick line, and therefore exhibits a complicated behavior.

FIG. 10 shows a rolling mill 1 having a load of 200 tons.
The upper and lower work rolls 3, 4 are brought into contact with each other, and at this time, the positions of the upper and lower horizontal supporting devices are fixed.
This is an example of measuring the horizontal deflection of the upper and lower work rolls 3 and 4 when the vertical work load is increased and decreased by idling. As the load increases, the pass line changes upward, the upper work roll 3 is displaced to the exit side, the lower work roll 4 is displaced to the entrance side, and the difference in horizontal deflection between the upper and lower work rolls 3, 4 increases. It can be seen that the horizontal deflection difference between the upper and lower work rolls 3 and 4 is proportional to the change amount of the pass line. Furthermore, in the conventional setting of the horizontal supporting device, when the pass line P changes,
As shown in FIG. 11, the offset is different in the width direction of the work roll, and the shape becomes an ear wave more than the original lateral rigidity of the rolling mill, which makes it difficult to control the shape of the rolling mill or causes the rolled material 2 to warp. . As described above, when the horizontal bending of the work rolls 3 and 4 is used for shape control, there is a difference in the bending force applied to the upper and lower work roll chocks, so that there is a problem that the horizontal bending cannot be effectively used. is there. 11B is a horizontal deflection distribution map of the work rolls 3 and 4, and FIG. 11C is a vertical deflection distribution map thereof. The present invention has been made to solve the above problems, and provides a plate rolling method capable of setting the horizontal relative position of the upper and lower work rolls to a predetermined position regardless of changes in the pass line. The purpose is.

[0008]

A first invention of a plate rolling method according to the present invention is directed to a work roll having a small upper and lower diameter and a work roll having a smaller upper and lower diameters in the horizontal direction or at a position slightly deviated from the horizontal in the horizontal direction. When performing the control to bend to the horizontal direction or supporting at the horizontal position, the vertical displacement of the upper and lower work rolls is estimated according to the change of the rolling load or the change of the tip position of the reduction device, and the estimated upper and lower work rolls are Based on the vertical position, the control amount for bending the upper and lower work rolls in the horizontal direction or the control amount for supporting the work rolls in the horizontal direction is controlled to be different. A second aspect of the invention is to control the upper and lower small-diameter work rolls and the upper and lower small-diameter work rolls to bend in the horizontal direction at the horizontal direction or at positions slightly deviated from the horizontal in the horizontal direction, or when supporting the work roll at the horizontal position, A device for measuring the change in relative vertical position between the upper and lower work rolls is installed in the body or bearing of the upper and lower work rolls, and the output is used to bend the upper and lower work rolls in the horizontal direction or to support them in the horizontal direction. It is characterized in that control for making a difference in control amount is performed. A third aspect of the invention is to control the upper and lower small-diameter work rolls and the upper and lower small-diameter work rolls to bend in the horizontal direction at the horizontal direction or at positions slightly deviated from the horizontal in the horizontal direction, or when supporting the work roll at the horizontal direction, Equipped with a roll-down device that can be used for rolling during continuous rolling, the vertical displacement of the upper and lower work rolls is estimated according to changes in the rolling load or the position of the roll-down device, and the estimated vertical position of the upper and lower work rolls is estimated. It is characterized in that the upper and lower rolling down devices are controlled so that the average of the above does not change. A fourth aspect of the invention is to control the upper and lower small-diameter work rolls and the upper and lower small-diameter work rolls to bend in the horizontal direction at the horizontal direction or at positions slightly deviated from the horizontal in the horizontal direction, or when supporting the work roll at the horizontal position, It is equipped with a rolling down device that can be driven down during continuous rolling, and is equipped with a device for measuring changes in the relative vertical position between the upper and lower work rolls and the rolling mill housing. It is characterized in that the vertical pressing device is controlled so that the average of the vertical positions of (1) does not change.

[0009]

In the first invention of the plate rolling method according to the present invention, the upper and lower small-diameter work rolls are controlled so as to be bent in the horizontal direction at the horizontal direction or at a position slightly deviated from the horizontal direction in the horizontal direction, or the horizontal position is controlled. The vertical displacement of the upper and lower work rolls that move in response to changes in the rolling load or the tip position of the reduction device when supporting the upper and lower work rolls is estimated based on the estimated vertical position of the upper and lower work rolls. Of the vertical work roll that moves in response to changes in the rolling load or the tip position of the reduction device, because the control amount that causes the horizontal deflection of the work roll or the control amount that supports it in the horizontal direction is differentiated. This offsets each other and the horizontal relative position of the upper and lower work rolls can be set to a predetermined position regardless of the change in the pass line. In the second aspect of the invention, the upper and lower work roll cylinders are controlled when the upper and lower small diameter work rolls are bent horizontally in a horizontal direction or in a position slightly deviated from the horizontal direction in the horizontal direction or when the work rolls are supported in the horizontal position. Section or bearing section is equipped with a device that measures the change in the relative vertical position with respect to the rolling mill housing, and this output can be used to determine the difference between the control amount that causes the upper and lower work rolls to bend in the horizontal direction or the control amount that supports the horizontal direction. Since the attachment control is performed, the vertical displacement of the upper and lower work rolls that move according to changes in the rolling load or the tip position of the reduction device is offset, and the horizontal relative positions of the upper and lower work rolls are adjusted regardless of the change in the pass line. Can be set in place. In the third invention, the upper and lower small-diameter work rolls are controlled to be bent horizontally in the horizontal direction or at positions slightly deviated from the horizontal in the horizontal direction, or are used during continuous rolling when supporting the work roll in the horizontal position. Equipped with a reduction device that can drive the reduction, the vertical displacement of the upper and lower work rolls is estimated according to the change of the rolling load or the position of the reduction device, and the estimated average vertical position of the upper and lower work rolls does not change. Since the upper and lower rolling down devices are controlled as described above, the change in the pass line is corrected and the horizontal relative position of the upper and lower work rolls can be set to a predetermined position. In the fourth invention, the upper and lower small-diameter work rolls are controlled to be bent horizontally in the horizontal direction or at positions slightly deviated from the horizontal in the vertical direction, or when the work rolls are supported in the horizontal direction, they are always used during rolling. It is equipped with a rolling down device that can drive the rolling, and a device that measures the change in the relative vertical position between the upper and lower work rolls and the rolling mill housing is installed in the body or bearing of the upper and lower work rolls. Since the vertical pressing device is controlled so that the vertical line does not change, the horizontal line relative position of the upper and lower work rolls can be set to a predetermined position by correcting the change of the pass line.

[0010]

【Example】

Example 1. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram showing a schematic configuration of a rolling apparatus of one demonstration example to which the present invention is applied. In the figure, reference numeral 1 denotes a rolling mill, which shows the overall configuration of this rolling mill. 2 is a rolled material.
Work rolls 3 and 4 extend the rolled material 2.
Intermediate rolls 5 and 6 directly back up the work rolls 3 and 4. Backup rolls 7 and 8 indirectly back up the work rolls 3 and 4 via the intermediate rolls 5 and 6. In this case, the upper and lower work rolls 3 and 4 are
It is formed to have a small diameter within a range that is allowable in terms of strength. Further, the upper and lower work rolls 3 and 4 are respectively provided with pressing rolls 9 and 10 which are pressed from the entering side in the sheet passing direction, and split rolls 11 which are pressed to the pressing rolls 9 and 10 in the direction of the work rolls 3 and 4. Twelve are sequentially arranged in a straight line. The split rolls 11 and 12 have a plurality of roll portions 11-i and 12-i (i = 1 to n, n = 5 in this embodiment) dispersedly arranged on their axes. The split rolls 11 and 12 have horizontal cylinders 13-i, 1 in which the ends thereof and the shaft between the rolls are arranged in the housing.
4-i (i = 0 to n, in this embodiment n = 5) rods are individually provided with pushing forces in the upper and lower work rolls 3 and 4 directions. Each horizontal cylinder 13
-i and 14-i are position detectors 15 that detect the amount of movement.
i, 16-i (i = 0 to n, n = 5 in this embodiment) are attached. The work roll horizontal support device is formed by the holding rolls 9, 10, the split rolls 11-i, 12-i, the horizontal cylinders 13-i, 14-i, and the position detectors 15-i, 16-i. . The horizontal cylinders 13-i, 14-i
Is equipped with servo valves 17-i and 18-i for supplying pressure oil.

The upper backup roll 7 has a chock 31 arranged via a load cell 21. The chock 32 of the lower backup roll 8 is pressed in the vertical direction by the hydraulic cylinder 20 for pressing, and a vertical pressing force is generated between the work rolls 3 and 4. This rolling force is detected by the load cell 21. In addition, the hydraulic cylinder for reduction 20
A displacement gauge 23 indicating the amount of vertical movement is attached to the. The servo valves 17-i and 18-i operate on the basis of the detection data obtained by the position detectors 15-i and 16-i and the data from the pass line change amount correction device 30, and a horizontal cylinder position setting device 24. Controlled by. The plate thickness of the rolled material 2 after stretching is measured by a plate thickness gauge 29.

The rolling operation by this rolling apparatus is as follows. Method Based on Elongation of Rolling Mill and Change in Plate Thickness from Initial Setting The cause of the change in the pass line is that in this embodiment, when the lower backup roll 8 is raised by the hydraulic cylinder 20 for reduction, the plate is removed. The following pass line changes occur on the upper and lower sides of the sand rolling mill 1.・ Rolling machine upper side: (a) Rolling machine elongation by applying rolling load ・ Rolling machine lower side: (b) Rolling machine elongation by applying rolling load, and (c) Plate thickness change from initial setting. And (b) can be obtained by the following. The sum of the elongations (a) and (b) of the rolling mill is the elongation of the entire rolling mill when a load is applied. The elongation increase δ of the entire rolling mill is δ = ΔP / M = (a) + (b), where the mill constant M and the load change ΔP from the standard rolling load (rolling load at initial setting) Therefore, if one of (a) and (b) is known, the other is also known. On the other hand, at the same time when the lower backup roll 8 is lifted by the hydraulic cylinder 20 for rolling down, the horizontal support device embedded in the housing also moves up. Since the upper and lower horizontal support devices are attached to the housing at substantially vertical symmetrical positions, the amounts of lift of the upper and lower horizontal support devices are substantially the same. Since the amount of elongation of the housing itself is as small as about 10% of that of the entire rolling mill, the amount of rise of the horizontal support device is also small. From the above, for example, with respect to (a), i) Ignoring the amount of rise of the horizontal support device and setting it as half of the elongation of the entire rolling mill, (a) = 1/2 × ΔP / M. ii) The amount of change on the upper side of the rolling mill and the amount of change of the horizontal direction support device with respect to the load change are measured off-line in advance, and the constant k is obtained from this by (a) = k × ΔP / M.

The above (c) can be obtained by the following. On the lower side of the rolling mill, even if the load does not change, the rolling mill moves by the amount corresponding to the change in the plate thickness (h), and the pass line changes. Therefore, it is necessary to consider the amount of change in plate thickness. As a method of obtaining the plate thickness change amount Δh, a plate thickness meter 29
It is calculated as Δh = ΔS−ΔP / M from the detected value at Δ, the change amount ΔS of the reduction device and the load change amount ΔP.

Subsequently, the horizontal cylinder position correction amount is obtained from the pass line change amount as follows. In FIG. 3, point A is the center point of the divided rolls 11 and 12, point B is the orthogonal point between the perpendiculars of the work rolls 3 and 4 and point A, point C is the original work roll center, point D is the cylinder position after correction. Work roll center, E; Work roll center after change of pass line, L
_{If 0} is the distance between AB, dPL is the path line change amount, ΔL is the horizontal support device correction amount, and angle BAC = θ ₀ , then ΔAB
C and ΔABD are right triangles and the angle B = 90 °. The cylinder position correction amount ΔL is as follows.

[0015]

[Equation 1]

Now, the angle BAC = 15 °, L ₀ = 450 mm
Assuming that, ΔL is as follows.

[0017]

[Table 1]

Therefore, by correcting the cylinder position by ΔL with respect to the change of the pass line, the work roll center is moved from the point E to the point D, and the work roll can be prevented from bending in the horizontal direction. However, this correction amount is roughly calculated by the sine of the angle from the horizontal plane of the horizontal support device (ΔL = dPL × sin 15 °), so there is almost no error, so the angle from the horizontal plane of the work roll horizontal support device is almost zero. You can give the sine of The signal of the pass run change amount calculated by the pass line change amount correction device 30 as described above is input to the horizontal cylinder position setting device 24, and the horizontal cylinder position setting device 24 calculates the vertical and horizontal cylinder correction amounts, A difference corresponding to the correction amount can be added to the upper and lower horizontal control amounts. The rolling load output from the load cell 21, the output signal from the plate thickness gauge 29, and the displacement amount output from the reduction cylinder displacement gauge 28 are input to the pass line variation correction device 30. The pass line change amount correction device 30 calculates the pass line change amount from the input signal, and further calculates and outputs the upper and lower horizontal cylinder position correction amounts for the change of the pass line. The calculation method of the pass line change amount and the calculation method of the horizontal cylinder position correction amount with respect to the pass line change are as described above. The horizontal cylinder position correction amount signal is input to the horizontal cylinder position setting device 24, and the cylinder position is adjusted so as to move the upper and lower horizontal cylinders by the respective correction amounts.
As described above, the upper and lower horizontal position control amounts are given a difference corresponding to the correction amount corresponding to the pass line change amount, and the servo valves 17-i and 18-i are instructed.

In order to carry out rolling with such a construction, first, the rolling cylinder 20 is moved to set a roll gap for obtaining a predetermined rolling amount for rolling. At this time, the amount of movement of the pass line is measured or estimated by the above method and input to the horizontal cylinder position setting device 24. The horizontal cylinder position setting device 24 calculates a horizontal direction control correction amount based on the pass line change amount, and operates the horizontal direction support device so as to make a difference between the control amounts of the upper and lower horizontal direction support devices. By performing this operation at intervals sufficiently short for control, it is possible to perform rolling while maintaining the horizontal relative position between the upper and lower work rolls.

Method for actually measuring changes in pass line A displacement gauge 28 mounted in the immediate vicinity of the restraining rolls 9 and 10 forming a horizontal support device provided in the rolling mill 1
By measuring the displacement of the upper and lower work roll chocks (not shown) or the work rolls 3 and 4, it is possible to measure the change dPL of the pass line in a state of canceling the rise of the horizontal support device due to the load change. Similarly, the horizontal cylinder correction amount ΔL is obtained from the above equation to perform horizontal position control correction.

In FIG. 4, the upper and lower work rolls are brought into contact with each other with a load of 200 ton, the positions of the upper and lower horizontal cylinders are fixed at this time, the work rolls are idled, and the vertical pressing force is increased or decreased to increase the horizontal pushing force. It is the measurement result of the vertical difference. In the conventional case, a complicated behavior appears such that the difference in the pushing force between the upper and lower sides is indicated by a mark. On the other hand, according to the present invention, it can be seen that there is almost no change in the vertical difference of the pushing force. Further, FIG. 5 shows the result of measuring the horizontal deflection of the upper and lower work rolls. According to the present invention, despite the rise of the pass line due to the change in load,
It can be seen that the horizontal deflection of the upper and lower work rolls hardly changes. As described above, according to the present invention, it is apparent that the work roll offset increase due to the change of the pass line can be prevented. In the above embodiment, the signal input to the horizontal cylinder position setting device is not only the pass line change amount correction signal according to the present invention, but also the cylinder position setting signal for the load and the horizontal cylinder position correction amount by feedback from the shape meter. Needless to say, the sum is the sum of the cylinder position setting signal by other control. Embodiment 2. FIG. FIG. 2 is an explanatory diagram showing a schematic configuration of a rolling apparatus of another demonstration example to which the present invention is applied. In the figure, the same components as those in FIG. 1 are denoted by the same reference numerals. Both of the upper and lower backup rolls 7 and 8 are provided with compression cylinders 19 and 20 in a chock so as to be vertically pressurized, whereby the work rolls 3 and 4 are vertically pressurized from above and below. It is designed to generate a rolling force. Pressure oil is supplied to the upper hydraulic cylinder 19 for pressure reduction via the servo valve 25, and hydraulic oil is supplied to the lower hydraulic cylinder 20 for pressure reduction via the servo valve 26. Servo valves 25 and 26 are hydraulic cylinders 19 for reduction.
It is controlled by a pass line change amount calculation device 27 that operates based on data from displacement gauges 22 and 23 that detect the operation amount of 20. The pass line correction with the above configuration is as follows. The pass line is calculated as follows. Each signal of the rolling load detected by the load cell 21, the rolling position change detected by the displacement gauges 22 and 23, and the strip thickness detected by the strip thickness gauge 27 is input to the pass line variation computing device 27, and the rolling mill upper side, The change amount of the lower pass line is calculated. The calculation result is output to the servo valves 25 and 26.

The cause of the change in the pass line is as follows: upper roll side: elongation on the upper side of the rolling mill + movement amount of the upper rolling reduction device (signal of the displacement gauge 29) Lower roll side: elongation on the lower side of the rolling mill + initial setting With respect to the elongation (upper side + lower side) of the entire housing of the rolling mill 1 and the change in plate thickness, the pass line change amount can be calculated in the same manner as in Example 1 separately from the change in plate thickness from time. The actual measurement of the change of the pass line above is as follows. It is detected by a work roll chock (not shown) or a displacement gauge 28, which measures the vertical relative displacement between the work rolls 3, 4 body and the housing of the rolling mill. The change amount of the pass line is measured by the displacement gauges 22 and 23, and the obtained output signal 22 is input to the servo valves 25 and 26 for setting the hydraulic cylinder position for reduction, and the positions of the reduction cylinders 19 and 20 are equal to the set value. Operate the reduction cylinder so that When rolling is performed without changing the pass line in such an operation: When the responsiveness of the rolling down device on the upper side of the rolling mill is equal to or lower than that on the lower side, the rolling down device on the upper side of the rolling mill is on the upper pass line. Using the amount of reduction corresponding to the amount of change, the lower side reduction device operates by being used for other control such as controlling the plate thickness.・ When the responsiveness of the rolling device on the upper side of the rolling mill is the same as that on the lower side,
Not only does the change of the pass line disappear, but the upper and lower rolling down devices are operated while being utilized for other control such as controlling the plate thickness. By performing this operation at intervals short enough to control the change of the pass line, the horizontal relative position between the upper and lower work rolls can be maintained while the horizontal support device is set as usual. , It is possible to carry out rolling.

[0023]

As described above, according to the present invention,
In a rolling mill with a horizontal support device for small-diameter work rolls, it is possible to prevent the horizontal relative position difference between the upper and lower work rolls from increasing due to an increase in load and maintain the horizontal relative position of the upper and lower work rolls at a predetermined value. Therefore, the shape of the rolled material can be obtained based on the lateral rigidity of the rolling device.
It is also possible to prevent the occurrence of defects such as warpage of the rolled material. Further, when the horizontal bending is used for the shape control, the horizontal bending can be effectively used because the constraint of the horizontal bending use range based on the deflection difference between the upper and lower work rolls is eliminated.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a schematic configuration of a rolling apparatus to which an embodiment of the sheet rolling method of the present invention is applied.

FIG. 2 is an explanatory diagram showing a schematic configuration of a rolling apparatus to which another embodiment of the sheet rolling method of the present invention is applied.

FIG. 3 is an explanatory view showing a mechanism for raising a pass line of a rolling mill.

FIG. 4 is an explanatory diagram showing a relationship between a vertical difference in pushing force of a rolling device and a rolling load.

FIG. 5 is a graph showing a result of measuring horizontal deflection of upper and lower work rolls.

FIG. 6 is an explanatory diagram showing a schematic configuration of an embodiment of a conventional rolling apparatus.

FIG. 7 is an explanatory diagram showing a bending force utilization range with respect to an allowable bending force of a work roll of a conventional rolling device.

FIG. 8 is an explanatory diagram showing changes in the offset amount between work rolls of a conventional rolling mill.

FIG. 9 is an explanatory diagram showing a relationship between a vertical difference of a pressing force and a rolling load of a conventional rolling measure.

FIG. 10 is an explanatory diagram showing a relationship between a rolling load of a rolling measure and a horizontal deflection of a work roll.

FIG. 11 is an explanatory diagram showing an outline of a deflection state of a work roll with respect to a pass line of a conventional rolling device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rolling equipment 2 Rolled material 3,4 Work rolls 5,6 Holding rolls 7,8 Backup rolls 9,10 Holding rolls 11,12 Dividing rolls 13,14 Horizontal cylinders 15,16 Position detectors 17,18 Servo valves 19,20 Hydraulic cylinder for reduction 21 Load cell 22,23 Displacement meter 24 Horizontal cylinder position setting device 25, 26 Servo valve 28 Displacement meter 29 Plate thickness gauge 30 Pass line change amount correction device

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location 8315-4E B21B 37/00 116 T (72) Inventor Naoki Ikeuchi 1-chome, Marunouchi, Chiyoda-ku, Tokyo No. 2 Japan Steel Pipe Co., Ltd. (72) Inventor Hisaaki Kataoka 1-2 1-2 Marunouchi, Chiyoda-ku, Tokyo Japan Steel Pipe Co., Ltd. (72) Inventor Shigefumi Hosoya 1-2-1 Marunouchi, Chiyoda-ku, Tokyo No. Nihon Steel Pipe Co., Ltd. (72) Inventor Tatsuo Toyofuku 1-2, Marunouchi, Chiyoda-ku, Tokyo Nihon Steel Pipe Co., Ltd.

Claims (4)

[Claims] 1. Rolling is performed when controlling the upper and lower small-diameter work rolls and the upper and lower small-diameter work rolls to bend in the horizontal direction or at positions slightly deviated from the horizontal in the horizontal direction, or when supporting the horizontal position. A control that estimates the vertical displacement of the upper and lower work rolls according to the change in the load or the tip position of the reduction device, and bends the upper and lower work rolls in the horizontal direction based on the estimated vertical position of the upper and lower work rolls. A plate rolling method, characterized in that control is performed to make a difference in the amount or the control amount for supporting in the horizontal direction. 2. The upper and lower small-diameter work rolls and the upper and lower small-diameter work rolls are controlled to bend horizontally or at a position slightly deviated from the horizontal in the horizontal direction, or when the horizontal position is supported, The work roll body or bearing is equipped with a device that measures the change in the relative vertical position between the work roll and the rolling mill housing, and the output is used to support the work rolls above and below the work roll in a controlled amount or in a horizontal position. A strip rolling method characterized by performing a control that gives a difference in a control amount. 3. The upper and lower small-diameter work rolls and the upper and lower small-diameter work rolls are controlled to be bent horizontally in a horizontal direction or at a position slightly deviated from the horizontal in the horizontal direction, or when the horizontal position is supported. Equipped with a rolling device that can be driven during rolling, it estimates the vertical displacement of the upper and lower work rolls according to changes in the rolling load or the position of the rolling device, and estimates the vertical position of the upper and lower work rolls. A plate rolling method characterized by controlling the upper and lower rolling devices so that the average does not change. 4. The upper and lower small-diameter work rolls and the upper and lower small-diameter work rolls are controlled so as to be bent horizontally in the horizontal direction or at positions slightly deviated from the horizontal in the horizontal direction, or are constantly supported at the horizontal position. Equipped with a reduction device that can be driven for reduction during rolling, a device that measures the change in relative vertical position between the upper and lower work rolls and the rolling mill housing is installed in the body or bearing of the upper and lower work rolls, and the output of the upper and lower work rolls is determined by this output. A strip rolling method characterized by controlling upper and lower rolling devices so that the average of vertical positions does not change.