JPH10225709A - Tandem mill and method for rolling metal plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To roll a metal plate into uniform thickness throughout the entire in the width direction by surely reducing edge drop to a material to be rolled having various thickness profiles. SOLUTION: In a tandem mill, a shift/cross rolling mill which is provided with a shift operating device 12 for shifting the work rolls whose end parts are tapered in the axial direction and a cross operating device 14 for crossing upper and lower work rolls on a 1st stand is installed and also constituted so that the amount of shift and cross angle for correcting the edge drop of the material to be rolled are determined based on the detected value of the profile of a base plate and target values and also, a controller 20 with which the work rolls are shifted at the amount of shift and the upper and lower work rolls are crossed at the cross angle by respectively outputting these detected amounts of shift and cross angle to the shift operating device 12 and cross operating device 14 is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for rolling a sheet material, particularly when rolling a sheet material such as a steel sheet in cold rolling or the like, in which edge drop is improved and the thickness distribution in the width direction is made uniform over the whole. The present invention relates to a tandem rolling mill and a method of rolling a sheet material.

[0002]

2. Description of the Related Art Among the thickness deviations in the width direction occurring in a sheet material (rolled material) during rolling, a sharp decrease in the thickness at both ends in the width direction is particularly called an edge drop. In order to obtain a good material to be rolled by rolling to make the thickness distribution uniform in the width direction, it is necessary to reduce the edge drop.

[0003] As one of the control methods for reducing the edge drop generated in such a plate material, a work roll (hereinafter, sometimes abbreviated as WR) having a tapered end portion on one side of the roll is conventionally used in the axial direction. Is used.

[0004] For example, Japanese Patent Publication No. 2-34241 discloses a thickness profile of a base plate at the entry side of a rolling mill (thickness distribution in a width direction), a roll gap distribution between upper and lower work rolls, and a rolling of the roll gap distribution. Disclosed is a method of estimating a thickness profile on the exit side of a rolling mill from a transfer rate to a material, collating the estimated value with a target thickness profile, and shifting a work roll to a position where the difference between the two is minimized. Have been.

As a similar control method, Japanese Patent Publication No. 2-4
364 has a shape in which each of a pair of work rolls is provided with a tapered portion that is tapered at least at one end to improve edge drop. There is disclosed a technique for reducing the edge drop by locating and improving the geometric shape of the roll gap at the both end portions. Further, as an example of applying this technique to a row of cold tandem rolling mills, the publication discloses a rolling mill arrangement in which a work roll having the tapered portion is incorporated in at least a first stand.

[0006] In addition, the document “Sheet Crown and Edge Drop Control Characteristics” (Preprints of the 45th Lecture Meeting on Plastic Working, P40
3-406, 1994), the upper and lower work rolls are crossed together with the backup rolls on each side, so that the plate thickness is formed between the upper and lower work rolls by a parabolic roll gap generated from the center in the width direction to the plate edge. It is disclosed that there is an effect of making a profile (width direction thickness distribution) uniform.

As a technique combining a roll cloth and a roll shift for upper and lower work rolls, for example, Japanese Patent Application Laid-Open No. Sho 57-206503 discloses a roll cross type rolling mill comprising an upper roll group and a lower roll group crossing at a predetermined angle. Discloses a technique for moving the relative position of a work roll in a roll group relative to a rolled material in the roll axis direction, thereby making the wear of the work roll uniform, reducing the frequency of roll polishing, and improving the unit consumption of the roll. Have been.

Japanese Patent Application Laid-Open No. 5-185125 discloses a method for reducing a defective area of a plate shape which occurs in a process of changing a roll cross angle when changing a running distance setting when a coil passes through a welding point (plate joint). A method of operating a roll shift and a work roll bend force in accordance with a change timing of a roll cross angle is disclosed. In this method, when the rolling conditions change greatly at the welding point of the coil, the transitional state of the roll cross angle setting from the start of the roll cross angle setting change to the end of the change for the purpose of maintaining a good plate shape for the purpose of maintaining the plate shape. In the above, the shift amount of the work roll is changed, and the roll cross angle and the work roll bend with respect to the succeeding coil are determined from the roll cross angle and the work roll bend force on the optimal curve showing the relationship between the roll cross angle and the work roll bend force with respect to the preceding coil. The work roll bend force is changed according to the optimum pattern so that the roll cross angle and the work roll bend force on the optimum curve indicating the relationship of the roll bend force can be changed in the shortest time.

[0009]

However, in the techniques disclosed in Japanese Patent Publication No. 2-34364 and Japanese Patent Publication No. 2-34241, the taper of the work roll is provided by polishing before rolling. It is impossible to change the amount or shape of the taper inside. Usually, the work roll is not replaced for each rolled material (coil), but is used for rolling several tens of rolls. Therefore, in the continuous rolling of dozens of coils, when the taper amount given to the work roll is increased, the edge drop of the base plate is effective for a large rolled material, but the edge drop of the base plate is reduced. For small rolled materials, there may be portions where the plate thickness becomes excessive near the inside of the plate edge,
Conversely, when the taper amount is reduced, it is effective for a rolled material having a small edge drop of the mother plate, but it should be sufficiently improved for a rolled material having a large edge drop of the mother plate. As a result, there arises a problem that the edge drop is improved for all the coils and a uniform thickness profile cannot be obtained in the entire width direction.

Further, in the method disclosed in the above-mentioned document "Sheet Crown / Edge Drop Control Characteristics", a parabolic roll gap generated from the center of the sheet width toward the end of the sheet gradually expands. Although there is an effect of improving (plate crown), there is a problem that there is no effect of reducing an edge drop which is a thickness deviation at a plate width end.

Japanese Patent Publication No. 57-206503 aims at preventing uneven wear of a work roll, and cannot directly control edge drop. The method described in Japanese Patent Publication No. 5-185125 aims at preventing the deterioration of the plate shape in the transition period of the change of the cross angle. The edge drop is disclosed in the Japanese Patent Publication No. 2-34364 and the like. There is a problem that it is impossible to expect an improvement effect more than that of the related art.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems. In particular, in the cold rolling, the width direction of the sheet material is varied with respect to the material to be rolled having various thickness profiles generated in the hot rolling step. A sheet rolling machine and a sheet rolling method capable of reliably reducing edge drop, which is a sharp reduction in thickness, generated at both ends of the sheet, and rolling the sheet to a uniform thickness over the entire width direction. That is the task.

[0013]

According to a first aspect of the present invention, there is provided a tandem rolling mill in which a plurality of stands of a rolling mill are provided, wherein at least the first stand has a work tapered at one end of a roll. A shift cross rolling mill equipped with a shift mechanism that shifts the roll in the axial direction and a cross mechanism that crosses the upper and lower work rolls is installed, and the amount of operation required to correct the edge drop amount of the material to be rolled is The shift amount and the cross angle are obtained, the obtained shift amount and the cross angle are output to the shift mechanism and the cross mechanism, respectively, so that the work roll is shifted by the shift amount and the upper and lower work rolls are crossed by the cross angle. By providing the means, the above problem has been solved.

According to a second aspect of the present invention, in the tandem rolling mill, an edge drop correction amount required to correct an edge drop amount to a target value is calculated, and the control means calculates a shift amount, a cross angle, and a shift amount. The shift amount and the cross angle necessary for correcting the edge drop of the material to be rolled are obtained based on the three relationships of the edge drop correction amount corresponding to the operation amount.

According to a third aspect of the present invention, in the tandem rolling mill, an edge drop correction amount required to correct an edge drop amount to a target value is calculated, and the control means determines a predetermined cross angle and a transfer angle. Holding the data on the relationship with the rate, the shift amount, the transfer rate, and, based on the relationship of the edge drop correction amount corresponding to the operation amount, the shift amount and the transfer rate at which the required edge drop correction amount is obtained. Is obtained, and a cross angle at which the obtained transfer rate is obtained is obtained based on the relationship between the cross angle and the transfer rate.

According to a fourth aspect of the present invention, there is provided a sheet material rolling method for rolling a material to be rolled using the tandem rolling mill according to the first, second or third aspect of the present invention.

According to a fifth aspect of the present invention, in the method of rolling a sheet material, the edge drop amount is measured at at least two points on one side in the width direction of the material to be rolled.

First, the concept of shift and cross for upper and lower work rolls having a tapered end on one side of the roll used in the present invention will be clarified with reference to FIGS.

As shown in FIG. 1, the shift is performed by shifting a work roll having a taper at one end of a point symmetrical roll end between upper and lower work rolls, as schematically shown in FIG. In the operation to move up and down in the opposite direction,
The shift amount is the movement amount, specifically, a distance X from the plate end of the material S to be rolled to the tapered start end E as shown in FIG. 2 in which the vicinity of one end of the upper roll is enlarged. The roll taper amount is defined as EH / EL in FIG.

As shown conceptually in FIG. 3, the rolling mill is viewed from above, the cross is an operation of intersecting the upper and lower work rolls with each other. It is 1/2 of the angle formed.

The inventors of the present invention have been concerned with rolling (hereinafter also referred to as single taper WR shift rolling) in which the work roll (single taper WR) having a tapered end on one side is adjusted in the axial shift position. As a result of extensive studies, the upper and lower work rolls are crossed by a predetermined amount and rolling is performed. As a result, it has been experimentally found that when the upper and lower work rolls cross by a predetermined amount, the transfer rate represented by the formula (1) changes. Is completed.

Transfer rate = (edge drop correction amount / roll gap change amount) × 100% (1)

Here, the transfer rate will be described.
The roll gap is the distance between the upper roll and the lower roll when there is no load, and the center value in the width direction of the work roll is used as a reference value. The roll gap change amount is 0 mm with the cross angle kept constant. This is the amount of change in the roll gap when changing the roll gap to a predetermined amount.

The roll gap change amount will be described with reference to FIG. 4, for example, which conceptually shows the relationship between the roll gap and the shift amount (distance from the plate edge). Since the roll gap with the cross angle of 0 ° and the shift amount of 0 mm is always zero, the roll gap change amount when the cross angle is 0 ° and the shift amount is moved from 0 mm to 50 mm is the distance from the plate edge. At 25 mm, this is shown in FIG.
Similarly, when the cross angle is θ1 and the roll gap having the shift amount of 0 mm hits the broken line, the roll gap change amount when the roll gap is moved to 50 mm is indicated by b in FIG.

The edge drop correction amount is the difference between the edge drop amount when rolling is performed with a roll having a shift amount of 0 mm and the edge drop amount when rolling is performed with a roll having a predetermined shift amount at a predetermined cross angle. is there. here,
The edge drop amount is a thickness deviation in the width direction at the plate end, and is defined as a deviation from the plate thickness at a certain reference position at the plate end, for example, at a position of 100 mm at the plate end.

That is, when the cross angle is set to a certain value, the one-sided taper WR shifts by 0 mm
And the amount of change in the edge drop of the sheet material after rolling by the one-side taper WR of each shift amount with respect to the amount of change in the roll gap when the plate material is moved by a predetermined amount.

FIG. 5 is a diagram showing an example in which when the upper and lower work rolls are crossed by a predetermined amount, the transfer rate expressed by the equation (1) changes. In the rolling of a steel plate for tinplate, the taper amount is 1/300. The cross angle was changed from 0 to 0.5 ° at intervals of 0.1 ° using a single taper WR, and the shift amount of the work roll was 50 m at each cross angle.
The transfer ratio at each distance from the plate edge shown on the horizontal axis when m is shown. In FIG. 5, the transfer rate in the case where the shift amount is 30 mm and the cross angle is 0.2 ° is also indicated by a broken line.

From this figure, it can be seen that, despite the work roll having the same taper amount, when the cross angle is increased, the transfer rate is increased except for a point 50 mm from the plate edge.

The reason why the transfer ratio changes in this way is that the rolling is performed by using a cross in combination with the single taper WR shift (hereinafter, also referred to as the single taper WR shift / rolling combined use of the cross), compared with the single taper WR shift alone. As the inclination of the taper part becomes steep, the rolling load at the plate edge decreases,
This is probably because the tension at the edge of the plate increases and the material fills the roll gap. Note that, even if the shift amount of the work roll is changed, if the cross angle is the same, the transfer rate except for the vicinity where the distance from the plate edge coincides with the shift amount is shown in FIG. In the case of 2 °, as shown also for the shift amount of 30 mm, it was almost the same as the value of the shift amount of 50 mm, and was irrelevant to the shift amount.

As described in detail above, by using a cloth in combination with the single taper WR shift, the transfer rate becomes variable even with a work roll having the same taper amount, which is substantially equivalent to making the taper amount variable. It turned out that an effect was obtained.

The present invention has been made on the basis of the above-mentioned findings, and has been designed to improve the edge drop by rolling using a single taper WR shift together with a cloth.

The reason why the present invention is effective will be described in further detail. Generally, when the thickness profile of the material to be rolled is a material to be rolled which has an edge drop at which the thickness is sharply reduced at the edge of the plate, When the flat roll is rolled, the thickness profile (upper side) as shown by reference numeral 601 in FIG. 6 is obtained. However, the improvement of the edge drop is insufficient. Even in the case of such a rolled material, the single taper W
According to the R shift rolling, the effect of improving the edge drop at the plate end is greater than that of the cross rolling of the flat roll, so that a good thickness profile as indicated by reference numeral 603 can be obtained. Therefore, when the taper amount of the work roll is appropriate for the edge drop amount, the single taper WR
Shift rolling is effective.

However, in the case of a type of material to be rolled in which the thickness reduction at the edge of the sheet is extremely large, if the sheet is rolled by a normal flat roll, the sheet having an extremely edge portion 701 shown in FIG. Since the thickness becomes a small thickness profile, it is necessary to increase the shift amount in order to improve this to a desired edge drop by single taper WR shift rolling using a work roll having the same taper amount as in the case of FIG. In this case, there is a thickness profile in which an excessively thick portion is generated inside as indicated by reference numeral 702. This phenomenon occurs when the taper of the work roll is small.
Since the shift amount needs to be further increased, the shift amount becomes more remarkable.

As described above, according to the single-tapered WR shift / cross roll combination of the present invention, the transfer rate increases as the cross angle increases, so that the transfer rate increases even for the rolled material having an extremely large edge drop. Without this, the effect of improving the edge drop at the plate edge can be increased, so that a plate thickness profile as shown by reference numeral 703 can be obtained without occurrence of an excessively thick portion. Therefore, the present invention is extremely effective for a rolled material having an extremely large edge drop.

When the shift amount and the cross angle are set by the single taper WR shift / cross combined rolling, the edge drop change amount with respect to the roll gap change amount determined by the work roll taper amount for each cross angle is set as a transfer rate in advance. In advance, the cross angle and the shift amount necessary for correcting the edge drop are set. The settings for these manipulated variables are
Analyze the relationship between the edge drop amount and the optimal shift amount and cross angle for each material to be rolled based on past results, make it into a table or model formula in advance, and make it based on this relationship Is also good. At this time, since rolling conditions such as rolling load and tension are factors that can affect the improvement characteristics of edge drop, these rolling conditions may be taken into consideration. In this case, more accurate cross angle and shift The amount can be set, and the accuracy of edge drop correction can be improved.

As described above, in the present invention, in the single taper WR shift rolling, the property that the transfer rate is changed by crossing the upper and lower work rolls is used, and the thickness profile before rolling and the target edge drop amount are adjusted. Accordingly, the roll cross angle that provides the optimum transfer rate is selected and set, and the appropriate roll shift amount is set under the transfer rate at the cross angle. It became possible to obtain a uniform thickness profile in the direction.

Further, by utilizing the excellent edge drop improvement characteristic by the single taper WR shift / cross cloth rolling,
Optimum edge drop control according to the thickness profile before rolling is now possible, so it is possible to improve edge drop and obtain a uniform thickness profile in the width direction for various materials to be rolled. became.

[0038]

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

FIG. 8 is a side view, including a block diagram, showing a schematic configuration of the tandem rolling mill (rolling equipment) of the first embodiment according to the present invention.

The rolling equipment used in this embodiment is the first
A rolling mill (hereinafter, also simply referred to as a shift-cross rolling mill) equipped with a shift mechanism that shifts a work roll tapered at one end of the roll at the stand and a cross mechanism that crosses the upper and lower work rolls is installed. In addition, a cold tandem rolling mill consisting of six stands in total.

In the tandem rolling mill, a shift operating device 12 for shifting the work roll 10 of the first stand to a predetermined position, a cross operating device 14 for crossing the upper and lower work rolls at a predetermined angle, and each of these operating devices 12, 14
And a first stand control device 20 for outputting a control signal to the first stand.

The control device 20 controls the base plate thickness profile before rolling measured by the base plate thickness profile detection device 16 installed on the exit side of a hot rolling mill (not shown) in the preceding process. When the information and the target value after cold rolling set by the plate thickness target value setting device 18 are input, the shift amount and the cross angle that are the operation amounts of the first stand are calculated,
The shift amount and the cross angle are output to the operating devices 12 and 14, respectively, and the work roll 10 is controlled to a predetermined shift amount and a cross angle.

The control device 20 holds data on the relationship between the predetermined cross angle and the transfer ratio, and stores the relationship between the shift amount, the transfer ratio, the edge drop correction amount corresponding to the operation amount, and the aforementioned relationship. A shift amount and a cross angle for correcting the edge drop of the material to be rolled are obtained based on a relationship between the cross angle and the transfer rate.

In this embodiment, the shift of the first stand
The cross rolling mill is a four-high rolling mill including a work roll and a backup roll, and this is schematically enlarged in FIG. 9A. As described above, the upper and lower work rolls 1
Although not shown in FIG. 0, taper is provided at one end of each of the opposite rolls, and these upper and lower work rolls 10 are respectively provided with backup rolls 22 from above and below.
And only the upper and lower work rolls cross each other.

In the rolling mill of the first stand, FIG.
(B) is provided with a shift device 22 and a cross device 24 schematically showing one work roll 10, and these are operated by the shift operation device 12 and the cross operation device 14 to shift the work roll 10 or cross the work roll 10. And so on.

The drive system of the shift device 22 may be composed of a hydraulic motor, an electric motor, or the like. or,
The cross device 24 is configured to cross the upper and lower work rolls 10 by moving the chock by pushing or pulling in at the entrance and exit of the WR chock. It can also be paired with a backup roll and crossed.

In the present embodiment, the rolled material is a tinplate steel plate having a width of 900 mm, which has been pickled after rolling, and has a taper amount of 1/3.
It was rolled with a work roll of 00.

Next, the effect of rolling the steel sheet using the rolling equipment will be described with reference to FIG.

In FIG. 10, reference numeral 1001 denotes a thickness profile at the end of the steel sheet when the steel sheet is rolled by a flat roll having no taper. This steel plate
At a position 10 mm from the edge of the plate, set the target edge drop amount to 0 to
By the conventional single taper WR shift rolling of 5 μm,
In order to improve the edge drop at a control point 10 mm from the edge of the plate, a shift amount of 45 mm was required. In addition,
How to determine the shift amount of 45 mm will be described later for convenience.

Accordingly, reference numeral 1002 denotes a thickness profile when one-side taper WR shift rolling is actually performed with a shift amount of 45 mm. In this case, the desired edge drop is improved at the control point, but an excessively thick portion is generated in the vicinity of a position 20 to 30 mm inside the control point, and a uniform thickness profile cannot be obtained. . Also, with only the conventional WR cloth, even when the cross angle is increased up to 1.0 °, which is the maximum angle at which stable threading can be performed,
As shown by the reference numeral 1003 in the thickness profile, sufficient edge drop improvement was not obtained.

Next, the case where the same steel sheet is rolled with the target edge drop amount at each position of 10 mm and 25 mm from the plate edge being 0 to 5 μm according to the present embodiment will be described. In the present embodiment, the shift amount and the cross angle of the one-side taper WR set when the plate material is rolled by the rolling mill are determined as follows.

That is, the relationship between the cross angle and the transfer rate is determined in advance as shown in FIG. 5, for example, and the relationship between the shift amount, the transfer rate, and the edge drop correction amount corresponding to the operation amount is determined. Based on the relationship between the cross-angle and the transfer rate, the cross-angle at which the calculated transfer rate is obtained is calculated based on the shift amount and the transfer rate at which the required edge drop correction amount is obtained. .

Then, the work roll is shifted by the shift amount obtained as described above, and control is performed to cross the upper and lower work rolls at the cross angle.

More specifically, at the position of Y mm from the edge of the sheet, the amount of edge drop correction required for setting the rolled sheet material to the target edge drop amount is the edge drop when the roll is rolled with a normal roll from the target edge drop amount. Give the deviation minus the amount.

Since the necessary edge drop correction amount has a relationship of roll gap change amount × transfer rate = edge drop correction amount, the roll gap change amount required for edge drop correction is required roll gap change amount = necessary edge. It is expressed by drop correction amount / transfer rate.

Therefore, the necessary edge drop correction amount is substituted into the term of the edge drop correction amount in the above equation (1),
Edge drop correction amount ED10 at 10mm position from plate edge,
Assuming that the edge drop correction amount ED25 at a position 25 mm from the plate end is the relationship between the roll gap change amount G, the transfer rate R, and the edge drop correction amount ED, the roll gap change amount G is determined by the work roll taper amount. Since the transfer rate R is determined only by the shift amount X and the transfer rate R is determined by the cross angle θ without depending on the shift amount X, the following equation (2) is used.
It is represented by the relationship of equation (3).

ED10 = G10 (X) · R10 (θ) (2) ED25 = G25 (X) · R25 (θ) (3)

The cross angle θ and the shift amount X satisfying the above conditions
Is determined based on FIG.

Next, a method of determining the shift amount and the cross angle suitable for correcting the edge drop will be described with reference to FIG.
This will be specifically described with reference to FIG.

FIG. 2 schematically shows the relationship between the work roll and the plate material S. Assuming that the shift position is X (mm), the roll gap change amount Gy ( Gm = (1/300) × (X−10) × 1000 at 10 mm from the plate edge (4) 10 ≦ X At a position 25 mm from the plate edge, G25 = (1/300) × ( X−25) × 1000 (5) 25 ≦ X. Note that x1000 in the above equations (4) and (5) is
This is a coefficient for setting the unit to μm.

In the case of flat roll rolling, the amount of edge drop correction at a position 10 mm from the plate edge is 33 μm from FIG. 10 and the amount of edge drop correction at a position 25 mm from the plate edge is 10 μm from FIG. From the above, at the roll gaps G10 and G25, Y
The transfer ratio Ry required to correct the edge drop at the mm position is: R10 = 33 / G10 at the position of 10 mm from the plate edge, (6) R25 = 10 / G25 at the position of 25 mm from the plate end ( 7)

From the relations of the above equations (4) to (7), the transfer ratio at the positions of 10 mm and 25 mm from the edge of the plate is:
When the shift amount X is 33 mm, the transfer rate is 10
When the shift amount is smaller than 33 mm, the transfer rate is larger than the above value, and when the shift amount is larger than 33 mm, the transfer rate is smaller than the above value.

On the other hand, from the relationship between the distance from the plate edge and the transfer rate with respect to the predetermined cross angle shown in FIG. 5, the cross angle is sequentially increased by a small amount, and the distance from the plate edge is obtained. The transfer rates at the positions of 10 mm and 25 mm have the relationship shown in Table 1 below.

[0064]

[Table 1]

That is, when the cross angle is 0.3 °, the transfer rate is 42% at a position 10 mm from the plate edge and 25 m from the plate edge.
It is 35% at the m position, which coincides with the transfer rate when the shift amount X is 33 mm. Therefore, the shift amount is 3
3 mm and the cross angle are determined to be 0.3 mm.

In the conventional single taper WR shift rolling alone, the thickness correction amount at the position of 10 mm from the end of the plate is also 33 μm from FIG. 10 and the transfer rate Ry is the cross angle shown in FIG. Since it is 28% from the value in the case of 0 °, the shift position X (mm) for correcting the plate thickness is:
When obtained from the following equation (8), the above 45 mm is obtained.

0.28 = 33 / G10 (8) G10 = (1/300) × (X−10) × 1000 10 ≦ X

As described in detail above, in the single taper WR shift / cross cloth rolling of the present embodiment, a desired edge drop is improved at the control point, and a uniform thickness profile is obtained even at other widthwise positions. To this end, it has been found that, when the shift amount X is 33 mm, a transfer rate of about 42% at the control point (10 mm from the plate edge) and a transfer rate of about 35% at a position 25 mm from the plate edge are required.

Therefore, in the present embodiment, as described above,
As the transfer rate closest to the above-mentioned transfer rate, the transfer rate at the cross angle of 0.3 ° is selected from FIG. 5, and the single taper WR shift is set such that the shift amount is 33 mm at the cross angle of 0.3 °. By performing cross-rolling,
As shown by reference numeral 1004 in FIG. 10, the edge drop was improved and a uniform thickness profile could be obtained without an excessively thick portion even inside the control point.

As described above, according to the present embodiment, it is possible to improve the edge drop which cannot be achieved by the conventional single taper WR shift rolling or simple cross rolling. As a result, the entire width direction can be improved. It has become possible to obtain a uniform plate profile over a wide range.

Next, a second embodiment according to the present invention will be described.

The rolling equipment used in the present embodiment, although not shown in its entirety, is a whole in which a six-high rolling mill including a work roll, an intermediate roll and a backup roll is installed as a shift cross rolling mill of the first stand. 5 is a cold tandem rolling mill of 5 stands, and the first embodiment is different from the first embodiment except that the base plate thickness profile detecting device 16 shown in FIG. Is substantially the same as

FIG. 11 schematically shows a six-high rolling mill which is a feature of the present embodiment installed on the first stand, and the upper and lower work rolls 10 are rolled in the same manner as in the first embodiment. Are tapered at one end, and a shift mechanism and a cross mechanism for the work roll 10 are provided. These upper and lower work rolls are supported by an intermediate roll 22 and a backup roll 20 from upper and lower directions. I have.

In the present embodiment, the material to be rolled is a SUS steel plate having a width of 1200 mm, which is pickled after rolling and annealed, and
The edge drop control point is 0 mm from the plate edge, that is, the plate edge, and the target edge drop amount is 0 to 5 μm. The work roll had a taper amount of 1/400, and the transfer rate was as shown in FIG.

Next, the effect of rolling the steel sheet using the rolling equipment will be described with reference to FIG.

In FIG. 13, reference numeral 1301 denotes a thickness profile at the end of the steel sheet when the steel sheet is rolled by a flat roll having no taper. This steel plate
In order to improve the edge drop at the above-mentioned control point by the conventional single taper WR shift rolling, the details are omitted, but if the calculation is performed in the same manner as in the first embodiment, the shift amount needs to be 45 mm.

Accordingly, reference numeral 1302 denotes a thickness profile in the case where one-side taper WR shift rolling is actually performed with a shift amount of 45 mm. In this case as well, the desired edge drop is improved at the control point, but an excessively thick portion occurs near the position 10 to 20 mm inside the control point, and a uniform thickness profile was not obtained. . Also, WR
With the cloth alone, as shown by the reference numeral 1303, the thickness profile when the cross angle was increased to 1.0 °, which is the maximum angle at which stable threading can be performed, was not able to obtain a sufficient improvement in edge drop.

Next, the rolling according to the present embodiment applied to the same steel plate will be described. Single taper WR of this embodiment
In the combined shift and cross rolling, calculation was performed according to the same principle as that of the first embodiment. As a result, a desired edge drop was improved at the control point, and a uniform thickness profile was obtained even at other width direction positions. For this purpose, it has been found that, when the shift amount X is 22 mm, a transfer rate of about 50% is required at the control point (0 mm from the plate edge) and about 40% at a position 15 mm from the plate edge.

Therefore, in the present embodiment, the transfer rate closest to the transfer rate is the cross angle of 0.5 ° from FIG.
The transfer rate at the time of (1) is selected.
By performing the single-tapered WR shift / cross cloth rolling with a shift amount of 20 mm at 5 °, as shown by reference numeral 1304 in FIG. Could be obtained.

As described above, according to the present embodiment, similarly to the case of the first embodiment, it is possible to improve the edge drop which cannot be achieved by the conventional single taper WR shift rolling or simple cross rolling. And as a result,
It has become possible to obtain a uniform plate profile over the entire width.

Next, a third embodiment according to the present invention will be described.

In this embodiment, the shift of the first stand
The cross rolling mill is a four-high rolling mill including a work roll and a backup roll, and this is schematically shown in FIG. The upper and lower work rolls 10 are similarly tapered at the ends on one side of the opposite rolls. These upper and lower work rolls are supported by backup rolls 22 from above and below, respectively. The rolls are substantially the same as in the first embodiment except that the rolls are integrally crossed.

In the present embodiment, the material to be rolled, the edge drop control point, the target edge drop amount, the taper amount of the work roll, and the transfer rate are all the same as those in the first embodiment.

Next, the effect of rolling the steel sheet using the rolling equipment will be described with reference to FIG.

In FIG. 15, reference numerals 1501 and 150
2 are the same as the reference numerals 1001 and 1002 shown in FIG. 10 of the first embodiment, and the desired edge drop is improved at the control point. In the vicinity, an excessively thick portion occurs, and a uniform thickness profile is not obtained. Also, WR
With the cloth alone, the improvement in edge drop was very small as shown by reference numeral 1503 in the sheet thickness profile when the cross angle was increased to 1.0 °, which is the maximum angle at which stable threading was possible.

Next, the rolling according to the present embodiment applied to the same steel sheet will be described. Single taper WR of this embodiment
In the combined rolling with shift and cloth, as in the first embodiment, in order to improve the desired edge drop at the control point and to obtain a uniform thickness profile at other positions, the shift amount is set to 33 mm and the control point is set to 33 mm. (10m from board edge
(m position), a transfer rate of 42% was required, and a transfer rate of about 35% was required at a position 25 mm from the edge of the plate.

Therefore, in this embodiment, the transfer rate at the cross angle of 0.3 ° is selected from FIG. 5 as the transfer rate closest to the transfer rate.
By performing the single-tapered WR shift / cross cloth combined rolling in which the shift amount is 33 mm in °, reference numeral 1 in FIG.
As indicated by reference numeral 504, a uniform thickness profile was obtained without an excessive thickness portion even inside the control point.

As described above, according to the present embodiment as well, it is possible to improve the edge drop which cannot be achieved by the conventional single taper WR shift rolling or simple cross rolling, and the uniformity can be obtained over the entire width direction. It has become possible to obtain a good plate profile.

Next, a fourth embodiment according to the present invention will be described.

The present embodiment comprises the same tandem rolling mill as that of the first embodiment, that is, six stands in which a first stage is provided with a four-stage shift cross rolling mill provided with work rolls having the same taper amount. Using a tandem rolling mill,
Rolling under the following rolling conditions, each rolling mill (stand)
The edge drop amount was examined on the output side, and the result is shown in FIG. As a comparative example, a tandem rolling mill in which substantially the same shift / cross rolling mill is arranged only on the fourth stand is used, and as a conventional example, a tandem rolling machine in which all stands are made of flat work rolls that do not shift or cross. In the case of rolling with a rolling mill, the edge drop amount on the exit side of each rolling mill was similarly examined, and the results are also shown in FIG.

(Rolling Conditions) In each case, the rolled material is a tinplate steel plate having a width of 900 mm, as in the first embodiment.

(1) Method of this embodiment (single taper WR shift / cross rolling only on first stand) Taper amount 1/300 Shift amount 33 mm cross angle 0.3 ° (2) Comparative example (single taper WR only on fourth stand) shift·
Cross rolling) Taper amount 1/300 Shift amount 50mm Cross angle 0.5 °

Either of the above (1) and (2), the one-sided taper W
Even in R shift cross rolling, the edge drop control point is
They are 10 mm and 25 mm from the plate edge. Further, the shift amount and the cross angle are determined so as to be close to the target edge drop within a range that does not deteriorate the sheet passing property such as the plate shape.

In the graph of FIG. 16 showing the edge drop amount on the base plate and each stand exit side, reference numeral 1601 denotes the result of the conventional example (all stand flat roll rolling), and reference numeral 1602 denotes the method of the present embodiment (first embodiment). Reference numeral 1603 indicates the result of a single taper WR shift / cross rolling only for one stand, and reference numeral 1603 indicates the result of a comparative example (single taper WR shift / cross rolling only for the fourth stand).

From FIG. 16, it is effective to improve the edge drop in the first stand in order to obtain a uniform thickness profile in the width direction with reduced edge drop on the exit side of the final stand. You can see that. This is considered because the edge drop is formed from the inside of the sheet width as the thickness of the entry side sheet of the material to be rolled is larger.

Next, a fifth embodiment according to the present invention will be described.

The tandem rolling mill according to the present embodiment is a cold tandem rolling mill composed of five stands in total, and four stages, each of which shifts and crosses only a work roll, to the first, second and third stands. Shift cross rolling mills are arranged.

In the present embodiment, rolling was performed using this tandem rolling mill under the following conditions. Also, as Comparative Example 1,
As a comparative example 2, 6 stands were added to the final 5th stand as a comparative example 2 by using a tandem rolling mill consisting of 5 stands, in which the 2nd, 3rd and 4th stands were also made up of 4 shift cross rolling mills.
Rolling was performed by a tandem rolling mill in which a shift cross rolling mill consisting of steps was arranged, and as a conventional example, a five-stand tandem rolling mill consisting of flat rolls in which all stands did not shift or cross. FIG. 17 shows the edge drop amount at a position 5 mm from the plate width on the exit side of each rolling mill (stand) when rolling is performed by each of these tandem rolling mills.

(Rolling conditions) In any case, the SUS having a sheet width of 1250 mm was pickled and annealed after hot rolling.
304 steel plate.

The edge drop control points in the single taper WR shift / cross rolling are 5 mm and 20 mm from the plate edge.

(1) Method of this embodiment (3 stand single taper WR shift / cross rolling) Taper amount Shift amount Cross angle First stand: 1/400, 42 mm, 0.5 ° Second stand: 1/400, 38 mm , 0.4 ° Third stand: 1/400, 35 mm, 0.4 ° (2) Comparative example 1 (3-stand single taper WR shift / cross rolling) Taper amount Shift amount Cross angle Second stand: 1/400, 40 mm, 0.5 ° Third stand: 1/400, 35 mm, 0.3 ° Fourth stand: 1/400, 35 mm, 0.3 ° (3) Comparative example 2 (final stand single taper WR shift cross rolling ) Taper amount Shift amount Cross angle Fifth stand: 1/400, 50mm, 0.5 °

The taper amount does not adversely affect the surface properties (gloss, etc.) of the steel sheet and is determined as an amount effective for edge drop control. The shift amount and the cross angle do not deteriorate the sheet passing property such as the plate shape. Within range, we decided to get closer to the target edge drop.

In FIG. 17, a graph showing the edge drop amount on the base plate and each stand exit side is indicated by reference numeral 17.
01 is a conventional example (all stand flat roll rolling), reference numeral 1702 is the method of the present embodiment (single taper WR shift cross rolling at the first to third stands), and reference numeral 1703 is comparative example 2 (fifth stand). Reference numeral 1704 indicates Comparative Example 1 (single taper WR shift / cross rolling at the second to fourth stands).

In order to obtain a uniform thickness profile in the width direction with reduced edge drop on the exit side of the final stand, at least the stand including the first stand is rolled by a shift cross rolling mill to improve the edge drop. Is effective. In this case, as compared with the comparative example in which the first stand does not employ the single taper WR shift / cross-rolling, the edge drop is obtained by performing the single taper WR shift / cross-rolling in the first to third stands as in the method of the present embodiment. It can also be seen that it is effective for improving.

This is considered to be because, also in the present embodiment, the edge drop is formed from the inside of the sheet width as the entry side sheet thickness of the material to be rolled is larger.

Although the present invention has been specifically described above, the present invention is not limited to the above-described embodiment, and can be variously modified without departing from the gist thereof.

For example, it goes without saying that the present invention can be applied even when the edge drop control point is at least 35 mm from the plate edge.

The specific configuration of the rolling equipment applicable to the present invention is not limited to the one described in the above embodiment.

For example, the rolling mill is not limited to a four- or six-high rolling mill, but may be a two-high rolling mill or the like. The number of stands is not limited to the six or five stands described in the embodiment, and may be a single stand. Optional.

The stand provided with the shift-cross mechanism for the tapered work roll is not limited to the first stand, and may be any stand. It may be.

The work roll may be a pair cross rolling mill that crosses the backup roll in pairs.

The plate material to be rolled is not limited to a steel plate, but may be another metal plate such as an aluminum plate or a copper plate.

[0113]

As described above, according to the present invention,
Edge drops can be reliably reduced for rolled materials having various thickness profiles, and a more uniform width-direction thickness distribution can be obtained as compared with the conventional rolling technology.

[Brief description of the drawings]

FIG. 1 is a front view conceptually showing a work roll.

FIG. 2 is an explanatory diagram showing a relationship between a shift position of a work roll and a plate material.

FIG. 3 is a plan view showing a cross angle of a work roll.

FIG. 4 is an explanatory view conceptually showing a roll gap change amount due to a shift;

FIG. 5 is a diagram showing a transfer rate when a work roll is rolled crossing a shift.

FIG. 6 is a graph showing an effect of improving edge drop of a material to be rolled in which a thickness reduction at a plate edge is relatively large

FIG. 7 is a diagram showing an effect of improving edge drop of a material to be rolled in which a thickness reduction at a plate edge is extremely large

FIG. 8 is an explanatory diagram showing a schematic configuration of a rolling facility applied to the first embodiment according to the present invention.

FIG. 9 is a schematic side view schematically showing a four-high rolling mill according to the first embodiment.

FIG. 10 is a diagram showing the effect of improving edge drop according to the first embodiment;

FIG. 11 is a schematic side view schematically showing a six-high rolling mill according to a second embodiment of the present invention.

FIG. 12 is a diagram showing a transfer rate of a SUS steel plate to be rolled in the second embodiment.

FIG. 13 is a diagram showing the effect of improving edge drop according to the second embodiment.

FIG. 14 is a schematic side view schematically showing a four-high rolling mill according to a third embodiment of the present invention.

FIG. 15 is a diagram showing the effect of improving edge drop according to the third embodiment;

FIG. 16 is a diagram showing the effect of improving edge drop according to the fourth embodiment;

FIG. 17 is a diagram showing the effect of improving edge drop according to the fifth embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Work roll 12 ... Shift operation device 14 ... Cross operation device 16 ... Base plate profile detection device 18 ... Sheet thickness profile target value setting device 20 ... Control device 22 ... Shift device 24 ... Cross device

Continued on the front page (51) Int.Cl. ⁶ Identification code FI B21B 38/02 B21B 37/00 116J 116M (72) Inventor Hisao Imai 1 Kawasaki-cho, Chuo-ku, Chiba-shi, Chiba Chiba Works Chiba Works (72) Inventor Tomohiro Kaneko 1 Kawasaki-cho, Chuo-ku, Chiba-shi, Chiba Chiba Works, Ltd. (72) Inventor Yasuhiro Yamada 1 Kawasaki-cho, Chuo-ku, Chiba-shi, Chiba Chiba Works

Claims (5)

[Claims] 1. A tandem rolling mill provided with a plurality of rolling mills, wherein at least a first stand is provided with a shift mechanism for axially shifting a work roll having a tapered end on one side of the roll, and a shift mechanism for vertically shifting the roll. A shift cross rolling mill equipped with a cross mechanism that crosses the work rolls is provided, and the shift amount and the cross angle are calculated as the operation amounts required to correct the edge drop amount of the material to be rolled. Tandem rolling, comprising a control means for outputting a shift amount and a cross angle to the shift mechanism and the cross mechanism, respectively, shifting a work roll to the shift amount, and crossing upper and lower work rolls at the cross angle. Machine. 2. The method according to claim 1, wherein an edge drop correction amount required to correct the edge drop amount to a target value is calculated, and wherein said control means corresponds to a shift amount, a cross angle, and these operation amounts. A tandem rolling mill, wherein a shift amount and a cross angle required to correct an edge drop of the material to be rolled are obtained based on three relationships of an edge drop correction amount. 3. The method according to claim 1, further comprising calculating an edge drop correction amount required to correct the edge drop amount to a target value, wherein the control means stores data on a relationship between a predetermined cross angle and a transfer rate. The shift amount, the transfer rate, and the shift amount and the transfer rate at which the required edge drop correction amount is obtained are obtained based on the relationship between the edge drop correction amount corresponding to the operation amount, and A tandem rolling mill, wherein a cross angle at which the obtained transfer rate is obtained is obtained based on a relationship between the cross angle and the transfer rate. 4. A method for rolling a sheet material, comprising rolling a material to be rolled using the tandem rolling mill according to claim 1, 2 or 3. 5. The method according to claim 4, wherein the edge drop amount is determined for one side in the width direction of the material to be rolled.
A method for rolling a plate material, wherein the measurement is performed at at least two points.