JP2003181505A - Rolling mill - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pair cross rolling mill which can reduce the slip speed (the relative slip ratio) between a work roll and a back-up roll. <P>SOLUTION: When the back-up rolls 22, 25 are on a drive side, a back-up roll drum 22b is divided in the roll axis direction, some of roll divided parts 32, 34 are fixed to back-up roll axes 22a, 25a and made as a drive part, and the other roll divided parts 31, 33, and 35 are provided freely rotatably to the back-up roll axis and made as a non-drive part. Also, when the back-up rolls are on the driven side, the back-up roll drum is divided in the roll axis direction and the roll divided parts are made mutually, independently, and freely rotatable. Also, the axis diameter of the back-up roll axis is made to be constant or to be different in proportion to the outer diameter of each roll divided part and the diameter of a bearing interposed between the back-up roll axis and each roll divided part is made to be constant or to be different in proportion to the outer diameter of each roll divided part. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a first roll group and a second roll group.
The present invention relates to a pair cross rolling machine in which a roll group intersects in the rolling plane, and is particularly useful when applied to a large cross rolling machine having a large crossing angle.

[0002]

2. Description of the Related Art FIG. 7 is a diagram showing a configuration of a main part of a conventional pair cross rolling mill, and FIG. 8 is a diagram showing a configuration of a main part of a conventional large cross rolling mill.

As shown in FIG. 7, a conventional rolling mill has an upper roll group 3 having a work roll 1 and a backup roll 2 for reinforcing the work roll 1, a work roll 4 and the work roll 4. A lower roll group 6 having a backup roll 5 for reinforcement is provided. The work rolls 1 and 4 are work roll shafts 1a and 4a which are rotary shafts.
Both end portions of the backup roll 2 are rotatably supported by work roll chocks 7 and 8, respectively.
Both ends of backup roll shafts 2a and 5a, which are rotating shafts, are rotatably supported by backup roll chocks 9 and 10, respectively. In the illustrated example, the backup rolls 2 and 5 are the work rolls 1 and 4 on the drive side.
Is the follower. That is, backup roll axis 2
A motor (not shown) is connected to a and 5a via a connection mechanism, and the backup rolls 2 and 5 are rotationally driven by this motor. Then, the torques of the backup rolls 2 and 5 are transmitted to the work rolls 1 and 4, respectively, and the work rolls 1 and 4 also rotate.

Moreover, the upper and lower roll groups 3 and 6 hold the roll shafts 1a and 2a of the upper rolls 1 and 2 in parallel with each other,
Further, the roll shafts 4a and 5a of the lower rolls 4 and 5 also intersect each other at an angle of 2θ in the rolling plane (in the plane parallel to the rolled material 11) while being held parallel to each other. That is, it is a pair cross. In this pair cross rolling machine, thin steel strip rolling (cross rolling) is performed by inserting a rolled material 11 which is a steel plate between upper and lower work rolls 1 and 4 in the rolling direction (direction of arrow A).

Such a pair cross rolling mill is a rolled material (strip plate).
It was also developed to improve the flatness of the plate and to build a plate crown, which is a plate thickness difference in the plate width direction. Due to the bending deformation of the work rolls 1 and 4 due to the rolling load, the rolled rolled material (strip plate) has a larger plate thickness at the center of the plate width than at the end of the plate width. So, this work roll 1,
The upper and lower roll groups 3 and 6 are crossed as a pair as described above in order to cancel the bending deformation of 4 and the like, whereby the gap between the upper and lower work rolls 1 and 4 is made into a plate of a rolled material (strip plate). The strips are made uniform in the width direction and have a uniform thickness.

At present, in order to improve the product material and improve the product performance such as the deep drawability represented by the Rankford value (r value), the upper and lower roll groups 3 and 6 are intersected. Increase the angle 2θ (for example, 2θ =
Large cross rolling mills (20 °, 40 °) have also been devised. In this large cross rolling mill, the roll cylinders of the work rolls 1 and 4 are provided with a roll diameter difference given by the formula (1). (Work roll diameter difference) = L ² tan ² θ / 2D (1) L: Work roll cylinder length θ: Half of the cross angle of the upper and lower work rolls (= cross angle) D: At the center of the roll axis of the work roll cylinder diameter

That is, as shown in FIG.
A concave crown is provided on the outer peripheral surface of the roll cylinder 4 and a convex crown is provided on the outer peripheral surface of the roll cylinders of the backup rolls 2 and 5. The outer peripheral surfaces of the roll cylinders of the backup rolls 2 and 5 with the crown and the outer peripheral surfaces of the work rolls 1 and 4 are in contact with each other.

[0008]

However, in the conventional backup rolls 2 and 5, the roll cylinders are not divided in the axial direction of the rolls and rotate integrally, so that the roll cylinders of the work rolls 1 and 4 are When there is a roll diameter difference given by the above formula (1), a slip velocity is generated between the work rolls 1 and 4 and the backup rolls 2 and 5.

The slip velocity is the difference between the peripheral velocity of the backup roll and the peripheral velocity of the work roll, and is expressed by equation (2). (Sliding speed) = V _Wi −V _Bi (2) V _Wi : peripheral speed of work roll V _Bi : peripheral speed of backup roll where i represents the roll axial position of the roll cylinder,
V _Wi and V _Bi represent peripheral velocities at respective positions of the roll cylinder in the roll axis direction.

The slip velocity is different at each position in the roll axial direction, and a value obtained by dividing the slip velocity by the reference roll peripheral velocity is called a relative slip ratio.

FIG. 9 shows a backup roll diameter of 1800 mm at the central portion in the roll axial direction of the backup roll cylinder, and a work roll diameter of 6 at the central portion in the roll axial direction of the work roll cylinder.
00 mm, roll roll length of backup roll and work roll is 2000 mm, crossing angle of upper and lower roll groups 2θ = 4
It is a figure which shows the distribution of the relative slip ratio in a roll axial direction in case of 0 degree (cross angle (theta) = 20 degree) and 2 (theta) = 20 degree (cross angle (theta) = 10 degree). Note that FIG. 9 shows the relative slip ratio distribution from the central part in the roll axial direction to the end part in the roll axial direction, and the relative slip ratio distribution of the conventional rolling mill is shown by the dotted line.

According to FIG. 9, the cross angle θ of the upper and lower roll groups
= 20 °, the relative slip ratio at the end of the roll axial direction (roll body end) reaches 55%, so the conventional backup rolls 2 and 5 that rotate integrally work as work rolls 1 and 4. There is concern about seizure between the backup rolls 2 and 5. The method of calculating the relative slip ratio shown in FIG. 9 will be described below with reference to examples.

From the above formula (1), the work roll diameter difference at the end in the roll axial direction is as follows. (Work roll diameter difference) = (2000 ² × tan ² 20) / (2 × 600) = 442 mm Then, at the position of 500 mm from the central portion in the roll axial direction, the peripheral speed of the backup roll and the peripheral speed of the work roll are If they are the same, the work roll diameter difference at this 500 mm position is as follows from the above equation (1). (Work roll diameter difference) = (1000 ² × tan ² 20) / (2 × 600) = 111 mm Further, the work roll diameter difference at the central portion in the roll axial direction is 0. Therefore, the relative slip ratio at the central portion in the roll axial direction is as follows. (Relative slip rate) = (0-111) /600≈-0.1
9 → (-19%) The relative slip ratio at the end in the roll axial direction is as follows. (Relative slip ratio) = (442-111) / 600≈0.
55 → (55%)

In view of the above problems, it is an object of the present invention to provide a pair cross rolling mill capable of reducing the slip velocity (relative slip ratio) between the work roll and the backup roll.

[0015]

[Means for Solving the Problems] First to solve the above problems
The rolling mill of the invention rolls a first roll group having a first work roll and a first backup roll and a second roll group having a second work roll and a second backup roll on a rolling surface. Crossing inside, the first and second backup rolls are the driving side, the first and second work rolls are the driven side, and a concave crown is attached to the outer peripheral surface of the roll cylinder of the first and second work rolls. In a pair cross rolling mill in which the outer peripheral surfaces of the first and second backup rolls are provided with a convex crown, the roll cylinders of the first and second backup rolls are divided into a plurality of rolls in the axial direction of the rolls. Of the split parts, a part of the roll split part is a drive part fixed to a backup roll shaft that is a drive shaft,
Another roll dividing unit is a non-driving unit rotatably provided on the backup roll shaft.

Further, the rolling mill of the second invention is the rolling mill of the first invention, wherein the drive portions of the first and second backup rolls are symmetrically positioned with respect to the central portion in the roll axial direction of the backup rolls. It is characterized by being provided.

The rolling mill of the third invention is the first or second rolling mill.
In the rolling mill of the invention, the backup roll shaft has a shaft diameter at the position of each non-driving portion that is different in proportion to the outer diameter of each non-driving unit, and is interposed between the backup roll shaft and each non-driving unit. It is characterized in that the diameter of each bearing installed also differs in proportion to the outer diameter of each non-driving portion.

Further, the rolling mill of the fourth invention comprises a first roll group having a first work roll and a first backup roll, a second work roll and a second backup roll. Intersect the two rolls in the rolling plane,
And the second work roll is the driving side, the first and second backup rolls are the driven side, and the concave crown is attached to the outer peripheral surface of the roll cylinder of the first and second work rolls.
And a pair cross rolling machine having a convex crown on the outer surface of the roll cylinders of the second backup rolls, the roll cylinders of the first and second backup rolls are divided into a plurality in the roll axial direction, and the plurality of roll dividing parts It is characterized by being able to rotate independently of each other.

The rolling mill of the fifth aspect of the invention is the rolling mill of the fourth aspect of the invention, in which the backup roll shaft has a different shaft diameter at the position of each roll splitting portion in proportion to the outer diameter of each roll splitting portion. The diameter of each bearing interposed between the backup roll shaft and each roll division is also different in proportion to the outer diameter of each roll division.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram showing a configuration of a main part of a pair cross rolling mill according to an embodiment of the present invention, FIG. 2 (a) is a diagram showing a configuration of a backup roll provided in the pair cross rolling mill, and FIG. 2 (b). ) Is a cross-sectional view taken along the line BB of FIG.

As shown in FIG. 1, the rolling mill of this embodiment has an upper roll group 23 having a work roll 21 and a backup roll 22 for reinforcing the work roll 21.
And a lower roll group 2 including a work roll 24 and a backup roll 25 that reinforces the work roll 24.
6 and. The work rolls 21 and 24 are rotatably supported at both ends of the work roll shafts 21a and 24a, which are rotating shafts, by work roll chocks (not shown). Similarly, the backup rolls 22 and 25 are backup roll shafts 22a and 25a, which are rotating shafts. Both ends of each are rotatably supported by backup roll chock (not shown).

In the illustrated example, the backup roll 2
2, 25 are drive sides, and the work rolls 21, 24 are driven sides. That is, the backup roll shafts 22a, 25
A motor (not shown) is connected to a through a connection mechanism, and this motor allows the backup rolls 22, 2 to be connected.
5 is rotationally driven. When the backup rolls 22 and 25 rotate, their torques are transmitted to the work rolls 21 and 24, respectively, and the work rolls 21 and 24 also rotate.

The upper and lower roll groups 23 and 26 hold the roll shafts 21a and 22a of the upper rolls 21 and 22 in parallel with each other, and the roll shafts 2 of the lower rolls 24 and 25.
4a and 25a also cross each other in the rolling plane (in the plane parallel to the rolled material 27) while being held parallel to each other. That is, it is a pair cross. In this pair cross rolling machine, a strip material 27, which is a steel plate, is inserted between the upper and lower work rolls 21 and 24 in the rolling direction (direction from the front to the back of the paper surface of FIG. 1) to perform thin steel strip rolling (cross rolling). I do.

Moreover, in this pair cross rolling mill, the crossing angle 2θ between the upper and lower roll groups 23, 26 is increased (for example, 2θ = 2).
(0 °, 40 °), and the roll cylinders 21b, 24b of the work rolls 21, 24 are provided with the roll diameter difference given by the above formula (1). That is, the roll cylinders 21b and 24b of the work rolls 21 and 24
The outer peripheral surface of the backup rolls 22 and 25 is provided with a concave crown, and the outer peripheral surfaces of the roll cylinders 22b and 25b of the backup rolls 22 and 25 are provided with convex crowns. The outer peripheral surface of the roll cylinder and the outer peripheral surfaces of the work rolls 21 and 24 are in contact with each other.

In this embodiment, as shown in FIGS. 1 and 2, the roll cylinder 2 of the backup rolls 22 and 25 is used.
Each of 2b and 25b is divided into five in the roll axial direction (roll dividing portions 31, 32, 33, 34, 35). Moreover, some of the roll dividing parts 31 to 35 are roll dividing parts 32 and 34 which are fixed to the backup roll shafts 22a and 25b, which are drive shafts, and the other roll dividing parts 31 and 35. Reference numerals 33 and 35 are non-driving portions rotatably provided on the backup roll shafts 22a and 25a with bearings 36 interposed between the backup roll shafts 22a and 25a. In addition, the roll dividing units 32 and 34, which are drive units, have backup rolls 22, 25.
Are provided symmetrically with respect to the central part in the roll axial direction, and have the same peripheral speed.

In this case, the drive unit (roll dividing units 32, 34) of the backup rolls 22, 25 is rotated by the motor, and the work roll 2 is rotated by the rotation of the drive unit.
1, 24 are rotated, and the non-driving parts (roll dividing parts 31, 33, 35) of the backup rolls 22, 25 are rotated by the rotation of the work rolls 21, 24.

Therefore, according to the present embodiment, the backup rolls 22 and 25 are divided into five in the roll axial direction, some of the roll dividing portions 32 and 34 are used as driving portions, and the other roll dividing portions 31, 33 and 35 are formed. Is a non-driving part, the peripheral speed of the work rolls 21 and 24 and the backup roll 2
It is possible to disperse the slip velocity, which is the difference between the peripheral velocity of 2,25 and the slip velocity, to be greatly reduced as compared with the prior art. For example, the backup roll diameter at the central portion in the roll axial direction of the backup roll is 1800 mm, the work roll diameter at the central portion in the roll axial direction of the work roll is 600 mm, the roll body length of the backup roll and the work roll is 2000 mm, and the crossing angle of the upper and lower roll groups is 2θ. = 40 ° (cross angle θ = 20 °) and 2
When θ = 20 ° (cross angle θ = 10 °), the relative slip ratio in the roll axis direction is dispersed as shown by the solid line in FIG. 9 to be 21% at the maximum, which is greatly reduced compared to the conventional case. . Therefore, it is possible to prevent the seizure between the work rolls 21 and 24 and the backup rolls 22 and 25 due to slippage. The method of calculating the relative slip ratio shown in FIG. 9 will be described below with an example.

As described above, from the above formula (1), the work roll diameter difference at the ends of the work rolls 21 and 24 in the roll axial direction is 422 mm. When the backup roll is divided into 5 as described above, for example, the roll dividing unit 35
Then, assuming that the peripheral speed of the backup roll and the peripheral speed of the work roll are the same at a position 850 mm from the central portion in the roll axial direction, the work roll diameter difference at the position of 850 mm is as follows from the equation (1). Become. (Work roll diameter difference) = (1700 ² × tan ² 20) / (2 × 600) = 319 mm Therefore, the relative slip ratio at this 850 mm position is as follows. (Relative slip rate) = (442-319) / 600≈0.
21 → (21%)

In the above description, the roll dividing parts 32, 34 located symmetrically with respect to the central part in the axial direction of the roll are used as driving parts, and the other roll dividing parts 31, 33, 35 are used as non-driving parts. It is not limited to this. For example, the roll dividing portions 31 and 35, which are symmetrically positioned with respect to the central portion in the roll axial direction, may be the driving portions, and the other roll dividing portions 32, 33, and 34 may be the non-driving portions. Alternatively,
Any one of the roll dividing units 31 to 35 such as the roll dividing unit 33 and the roll dividing unit 34 (for example, the roll dividing unit 33,
It is also possible to use only the roll dividing unit 34) as a driving unit and the other roll dividing units as non-driving units.

Further, in the above, the number of roll divisions of the backup rolls 22 and 25 is set to 5 in consideration of the constraints in actual production, but the number is not necessarily limited to this, and the number of roll divisions is 5 or more. However, it may be divided into five or less.

In the above, the backup roll 22,
Although the case where 25 is the driving side and the work rolls 21 and 24 are the driven sides has been described, the present invention is conversely the work roll 2
The present invention can also be applied to the case where 1 and 24 are the driving side and the backup rolls 22 and 25 are the driven side. In the latter case, the roll cylinder 22 of the backup rolls 22, 25
b and 25b are divided into a plurality in the axial direction of the roll (for example, five divisions as shown in FIG. 2), and the plurality of roll divided portions are rotatable independently of each other. In this case, the work rolls 21 and 24 are rotated by the motor,
Backup rolls 22,25 by rotation of 1,24
Therefore, the plurality of roll dividing parts of (3) are independently rotated. In order to make the plurality of roll divisions of the backup rolls 22 and 25 rotatable independently of each other,
Backup roll axis 2 for all of these multiple roll divisions
2a, 25a may be rotatably provided by interposing a bearing or the like, or one roll division may be fixed to the backup roll shafts 22a, 25a and the other roll division may be provided for the backup roll shaft 22a. ，
It may be rotatably provided by interposing a bearing with respect to 25a.

Also in this case, the sliding speed, which is the difference between the peripheral speed of the work rolls 21 and 24 and the peripheral speed of the backup rolls 22 and 25, can be dispersed and greatly reduced as compared with the conventional case. It is possible to prevent seizure or the like between the 24 and the backup rolls 22 and 25 due to slippage.

Next, the shaft diameter of the backup roll shaft and the diameter of the bearing will be described in detail with reference to FIGS.

FIG. 3 shows a configuration in which the backup roll is on the drive side (the work roll is on the driven side) and the backup roll shaft has a constant shaft diameter. 3 (a) is a longitudinal sectional view of the backup roll, FIG. 3 (b).
FIG. 4 is a sectional view taken along the line C-C of FIG.

The backup rolls 22 and 25 shown in FIG.
Then, the backup roll cylinders 22b and 25b are divided into five in the roll axial direction (roll dividing portions 31, 32, 33, 34, 3).
5), the roll dividing parts 32 and 34 are fixed to the backup roll shafts 22a and 22b to serve as driving parts, and the roll dividing parts 31, 33 and 35 are formed into bearings 36A and 36B,
The backup roll shafts 22a and 25a are rotatably provided to the non-driving portion via 36C.

The backup rolls 22 and 2
The two backup roll shafts 22a and 22b have the same shaft diameter over the entire range of the backup roll cylinders 22b and 25b. Therefore, the diameters of the bearings 36A, 36B, 36C interposed between the backup roll shafts 22a, 25a and the roll dividing portions 31, 33, 35 are also small and the same. In this case, the backup roll shafts 22a and 25a have a simple cylindrical shape, and all the bearings 36A to 36C have a small diameter and the same diameter, so that the manufacturing cost is reduced. Although the bearings 36A to 36C are rolling bearings,
Instead of this, a slide bearing (not shown) or the like may be used.

FIG. 4 shows a configuration in which the backup roll is on the drive side (the work roll is on the driven side) and the backup roll shafts have different shaft diameters. 4 (a) is a longitudinal sectional view of the backup roll, FIG. 4 (b).
[Fig. 4] is a sectional view taken along the line DD of Fig. 4 (a).

The backup rolls 22 and 25 shown in FIG.
Then, as in the case of FIG. 3, the backup roll cylinder 22b,
25b is divided into five in the axial direction of the roll (roll dividing portions 31, 3
2, 33, 34, 35), and the roll dividing sections 32, 34
Is fixed to the backup roll shafts 22a and 22b to serve as a drive unit, and the roll dividing units 31, 33, and 35 are rotatably provided on the backup roll shafts 22a and 25a through bearings 36D, 36E, and 36F, respectively. Has become.

Then, the backup rolls 22, 2
The two backup roll shafts 22a and 22b have different shaft diameters at the positions of the roll dividing portions 31 to 35 in proportion to the outer diameters of the roll dividing portions 31 to 35. That is, the backup roll shaft portions 22a-1 and 25a at the positions of the non-driving portions (roll dividing portions 31 and 35) having a small outer diameter.
Compared with the shaft diameters of -1, 22a-5 and 25a-5, the shaft diameters of the backup roll shaft portions 22a-3 and 25a-3 at the position of the non-driving portion (roll dividing portion 33) having a large outer diameter are larger. Has become. Therefore, the backup roll shafts 22a and 25a and the roll dividing units 31, 33 and 35
Bearings 36D, 36E, 36F interposed between and
The diameter of is also different in proportion to the outer diameter of the roll dividing portions 31 to 35. That is, the bearing 36D at the position of the non-driving portion (roll dividing portions 31, 35) having the smaller outer diameter,
The diameter of the bearing 36E at the position of the non-driving portion (roll dividing portion 33) having a large outer diameter is larger than the diameter of 36F.

In this case, the bearings 36D, 36
The diameters of E and 36F are the non-driving portions (roll dividing portions 31 and 3).
3, 35), the bearing life is extended and stable rotation performance of the non-driving portion is obtained. Although the bearings 36D to 36F are rolling bearings, sliding bearings (not shown) or the like may be used instead of them.

FIG. 5 shows a structure in which the backup roll is on the driven side (the work roll is on the driving side) and the backup roll shaft has a constant shaft diameter. 5 (a) is a longitudinal sectional view of the backup roll, FIG. 5 (b).
FIG. 6 is a sectional view taken along line EE of FIG.

The backup rolls 22 and 25 shown in FIG.
Then, the backup roll cylinders 22b and 25b are divided into five in the roll axial direction (roll dividing portions 31, 32, 33, 34, 3).
5) Then, the plurality of roll dividing portions 31 to 35 are rotatably provided on the backup roll shafts 22a and 25a through the bearings 36G, 36H, 36I, 36J and 36K, so that they can be independently rotated. Has become.

The backup rolls 22, 2
The two backup roll shafts 22a and 22b have the same shaft diameter over the entire range of the backup roll cylinders 22b and 25b. Therefore, the diameters of the bearings 36G to 36K interposed between the backup roll shafts 22a and 25a and the roll dividing portions 31 to 35 are also small and the same. In this case, the backup roll shafts 22a and 25a have a simple cylindrical shape, and
Since all the bearings 36G to 36K have a small diameter and have the same diameter, the manufacturing cost is reduced. Although the bearings 36G to 36K are rolling bearings, instead of this,
A slide bearing (not shown) or the like may be used.

FIG. 6 shows a structure in which the backup roll is on the driven side (the work roll is on the driving side) and the backup roll shafts have different shaft diameters. 6 (a) is a longitudinal sectional view of the backup roll, FIG. 6 (b).
FIG. 7 is a sectional view taken along the line FF of FIG.

The backup rolls 22 and 25 shown in FIG.
Then, as in the case of FIG. 5, the backup roll cylinder 22b,
25b is divided into five in the axial direction of the roll (roll dividing portions 31, 3
2, 33, 34, 35), and the plurality of roll dividing parts 31 to 35 form bearings 36L, 36M, 36N,
Backup roll shaft 22a through 36O and 36P,
By being rotatably provided on 25a, they can be rotated independently of each other.

The backup rolls 22, 2
The two backup roll shafts 22a and 22b have different shaft diameters at the positions of the roll dividing portions 31 to 35 in proportion to the outer diameters of the roll dividing portions 31 to 35. That is, the outer diameter of each of the roll dividing portions 31 to 35 is equal to that of the roll dividing portions 31 and 3.
5, the roll dividing parts 32 and 34, and the roll dividing part 33 are increased in this order.
a-1, 22a-2, 25a-2, 22a-3, 25a
-3, 22a-4, 25a-4, 22a-5, 25a-
5 is a backup roll shaft portion 22a-1, 25a-
1, 22a-5, 25a-5, backup roll shaft portions 22a-2, 25a-2, 22a-4, 25a-4,
The backup roll shaft portions 22a-3 and 25a-3 are increased in this order.

Therefore, the backup roll shaft 22a,
The diameters of the bearings 36L to 36P provided between the roller 25a and the roll dividing portions 31 to 35 are also the same as those of the roll dividing portions 31 to 31P.
It is different in proportion to the outer diameter of 35. That is, the outer diameter of each of the roll dividing portions 31 to 35 increases in the order of the roll dividing portions 31 and 35, the roll dividing portions 32 and 34, and the roll dividing portion 33. Therefore, the bearings 36L to at the positions of the roll dividing portions 31 to 35, respectively. 36P is the bearing 36L, 3
6P, bearings 36M and 36O, and bearing N are larger in this order.

In this case, the bearings 36L to 36P
Since the diameter of the roller is different in proportion to the outer diameter of each of the roll dividing sections 31 to 35, the bearing life is extended and stable rotation performance of the non-driving section is obtained. The bearings 36L to 36P are rolling bearings, but instead of this,
A slide bearing (not shown) or the like may be used.

[0050]

As described above in detail with the embodiments of the invention, the rolling mill according to the first invention includes a first roll group having a first work roll and a first backup roll, The second work roll and the second roll group having the second backup roll intersect in the rolling plane to
And the second backup roll is on the driving side, the first and second work rolls are on the driven side, and a concave crown is attached to the outer peripheral surface of the roll cylinder of the first and second work rolls.
And a pair cross rolling machine having a convex crown on the outer surface of the roll cylinders of the second backup rolls, the roll cylinders of the first and second backup rolls are divided into a plurality in the roll axial direction, and the plurality of roll dividing parts Among them, a part of the roll dividing parts is a driving part fixed to a backup roll shaft which is a driving shaft, and another roll dividing part is a non-driving part rotatably provided on the backup roll shaft.

The rolling mill of the second invention is the rolling mill of the first invention, wherein the drive units of the first and second backup rolls are symmetrically positioned with respect to the central portion in the roll axial direction of the backup rolls. It is characterized by being provided.

Therefore, according to the rolling mill of the first or second aspect of the present invention, the slip velocity, which is the difference between the peripheral velocity of the work roll and the peripheral velocity of the backup roll, can be dispersed and reduced significantly compared to the conventional case. . Therefore, it is possible to prevent seizure or the like from occurring due to slippage between the work roll and the backup roll.

The rolling mill of the third invention is the first or second rolling mill.
In the rolling mill of the invention, the backup roll shaft has a shaft diameter at the position of each non-driving portion that is different in proportion to the outer diameter of each non-driving unit, and is interposed between the backup roll shaft and each non-driving unit. It is characterized in that the diameter of each bearing installed also differs in proportion to the outer diameter of each non-driving portion.

Therefore, according to the rolling mill of the third invention,
Since the diameter of the bearing differs in proportion to the outer diameter of each non-driving portion (roll division portion), the bearing life is extended and stable rotation performance of the non-driving portion can be obtained.

Further, the rolling mill of the fourth invention comprises a first roll group having a first work roll and a first backup roll, a second work roll and a second backup roll. Intersect the two rolls in the rolling plane,
And the second work roll is the driving side, the first and second backup rolls are the driven side, and the concave crown is attached to the outer peripheral surface of the roll cylinder of the first and second work rolls.
And a pair cross rolling machine having a convex crown on the outer surface of the roll cylinders of the second backup rolls, the roll cylinders of the first and second backup rolls are divided into a plurality in the roll axial direction, and the plurality of roll dividing parts It is characterized by being able to rotate independently of each other.

Therefore, also in the rolling mill according to the fourth aspect of the present invention, the sliding speed, which is the difference between the peripheral speed of the work roll and the peripheral speed of the backup roll, can be dispersed to be significantly reduced as compared with the conventional one. It is possible to prevent the occurrence of image sticking due to slippage between the backup roll.

The rolling mill of the fifth aspect of the invention is the rolling mill of the fourth aspect of the invention, in which the backup roll shaft has a different shaft diameter at the position of each roll splitting portion in proportion to the outer diameter of each roll splitting portion. The diameter of each bearing interposed between the backup roll shaft and each roll division is also different in proportion to the outer diameter of each roll division.

Therefore, according to the rolling mill of the fifth invention,
Since the diameter of the bearing differs in proportion to the outer diameter of each roll division, the life of the bearing is extended and stable rotation performance of the non-driving portion is obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing a main configuration of a pair cross rolling machine according to an embodiment of the present invention.

FIG. 2 (a) is a diagram showing a configuration of a backup roll provided in the pair cross rolling mill, and FIG. 2 (b) is B in FIG. 2 (a).
FIG. 6 is a cross-sectional view taken along line B-arrow.

FIG. 3 is a configuration diagram of a backup roll when the backup roll is a drive side (work roll is a driven side) and the backup roll shaft has a constant shaft diameter.

FIG. 4 is a configuration diagram of a backup roll when the backup roll is a drive side (work roll is a driven side) and the backup roll shafts have different shaft diameters.

FIG. 5 is a configuration diagram of a backup roll when the backup roll is a driven side (work roll is a driving side) and the backup roll shaft has a constant shaft diameter.

FIG. 6 is a configuration diagram of a backup roll when the backup roll is a driven side (work roll is a driving side) and the backup roll shafts have different shaft diameters.

FIG. 7 is a diagram showing a main part configuration of a conventional pair cross rolling machine.

FIG. 8 is a view showing a main configuration of a conventional large cross rolling mill.

FIG. 9 is a diagram showing a distribution of relative slip ratios in the roll axis direction.

[Explanation of symbols]

21 work roll 21a Work roll axis 21b Work roll body 22 Backup Roll 22a Backup roll axis 22a-1 to 22a-5 Backup roll shaft part 22b Backup roll body 23 Upper roll group 24 work rolls 24a Work roll axis 24b work roll cylinder 25 backup roll 25a Backup roll axis 25a-1 to 25a-5 Backup roll shaft part 25b backup roll body 26 Lower rolls 27 rolled material 31-35 Roll splitting unit of backup roll 36, 36A-36P bearings

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor, Joh Iwatani             4-6-22 Kannon Shinmachi, Nishi-ku, Hiroshima City, Hiroshima Prefecture               Inside Mitsubishi Heavy Industries Hiroshima Works (72) Inventor Norio Hashimoto             4-6-22 Kannon Shinmachi, Nishi-ku, Hiroshima City, Hiroshima Prefecture               Mitsubishi Heavy Industries Ltd. Hiroshima Research Center (72) Inventor Shirogane Shirogane             4-6-22 Kannon Shinmachi, Nishi-ku, Hiroshima City, Hiroshima Prefecture               Mitsubishi Heavy Industries Ltd. Hiroshima Research Center (72) Inventor T. Takeguchi             4-6-22 Kannon Shinmachi, Nishi-ku, Hiroshima City, Hiroshima Prefecture               Inside Mitsubishi Heavy Industries Hiroshima Works F-term (reference) 4E016 AA03 BA02 BA10 CA07 DA01                       DA04 DA15

Claims (5)

[Claims] 1. A rolling surface in which a first roll group including a first work roll and a first backup roll and a second roll group including a second work roll and a second backup roll are provided. , The first and second backup rolls are the drive side, and the first and second work rolls are the driven side.
In addition, in a pair cross rolling machine in which a concave crown is provided on the outer peripheral surfaces of the roll cylinders of the first and second work rolls and a convex crown is provided on the outer peripheral surfaces of the roll cylinders of the first and second backup rolls, And the roll cylinder of the second backup roll is divided into a plurality in the axial direction of the roll, and among the plurality of roll dividing parts, a part of the roll dividing parts is a drive part fixed to the backup roll shaft which is the drive shaft, and A rolling mill characterized in that the roll dividing unit is a non-driving unit rotatably provided on a backup roll shaft. 2. The rolling mill according to claim 1, wherein the drive parts of the first and second backup rolls are provided at symmetrical positions with respect to the central part of the backup roll in the roll axial direction. Rolling machine to do. 3. The rolling mill according to claim 1, wherein the backup roll shaft has a shaft diameter at a position of each non-driving portion which differs in proportion to an outer diameter of each non-driving portion. The rolling mill characterized in that the diameter of each bearing interposed between the non-driving portion and the non-driving portion also varies in proportion to the outer diameter of the non-driving portion. 4. An in-plane rolling method comprising: a first roll group having a first work roll and a first backup roll; and a second roll group having a second work roll and a second backup roll. , The first and second work rolls are on the drive side, and the first and second backup rolls are on the driven side,
In addition, in a pair cross rolling machine in which a concave crown is provided on the outer peripheral surfaces of the roll cylinders of the first and second work rolls and a convex crown is provided on the outer peripheral surfaces of the roll cylinders of the first and second backup rolls, And a roll cylinder of the second backup roll, which is divided into a plurality in the axial direction of the roll, and the plurality of roll dividing portions are rotatable independently of each other. 5. The rolling mill according to claim 4, wherein the backup roll shaft has a shaft diameter at the position of each roll division that is different from each other in proportion to the outer diameter of each roll division. The rolling mill characterized in that the diameters of the bearings respectively interposed between the roll divisions also differ in proportion to the outer diameters of the roll divisions.