JPH09122711A - Cold rolling mill - Google Patents

Abstract

PROBLEM TO BE SOLVED: To impart shear deformation in the width direction to the surface of a steel strip and to improve gloss by providing a cam device for continuously oscillating upper and lower work rolls in the opposite direction to each other in the axial direction in the rotation of the work rolls. SOLUTION: The cam device 1 is provided between one end of a roll barrel part 2 and a roll chock 4 and the cam device 1 consists of a cam 11 as a driver and a follower 10 fixed on the roll chock 4. A radial bearing 15 for rotatably supporting a roll shaft 9 in the roll chock 4 is provided and the roll can be slid in the axial direction. In this way, a rolling mill having gloss improving function can easily be obtained only by modifying the roll and the roll chock.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling mill for imparting luster to the surface of a steel strip during cold rolling, and more specifically to a function of continuously swinging upper and lower work rolls in the axial direction. The present invention relates to a cold rolling mill provided.

[0002]

2. Description of the Related Art While rolling a work roll of a cold rolling mill,
The work roll shift for axial movement is used for various purposes.

That is, 1) the work roll is processed into a special shape such as a cubic curve or an end taper, and the amount by which the upper and lower work rolls are axially shifted is adjusted according to the width of the steel strip. Control the profile and flatness of. 2) Since the wear of the roll surface at the portion where both edges of the steel strip hit is significant, the roll is shifted to disperse the wear in the axial direction. 3) At the time of roll polishing, the steel strip is subjected to relative sliding in the axial direction of the roll and the steel strip by utilizing fine irregularities called grinding marks carved in the circumferential direction on the surface thereof. Shear deformation is applied to the surface in the width direction to increase the gloss of the steel strip surface.

Japanese Unexamined Patent Publication No. 7-100503 discloses a rolling method by work roll shift for the purpose of 3) above.

[0005]

The coefficient of friction between the work roll and the steel strip in cold rolling is determined by the coefficient of friction in the rolling direction in normal rolling and the direction perpendicular to the rolling direction when the roll is axially shifted. The latter is larger when compared with the friction coefficient. That is, when the rolls are shifted, a large resistance acts due to the friction between the rolls and the steel strip and the friction between the intermediate roll or the backup roll that is in contact with the work roll. If the shift speed is increased, the equipment will be large, so in the case of a rolling mill that shifts work rolls by normal hydraulic pressure, the shift speed is 0.2
It is about mm / sec. However, in the case of the above 1) and 2), there is no need to frequently switch the shift amount during rolling, so there is no problem with the above shift speed,
A setup control method is used when rolling conditions are switched.

However, in the case of shifting in order to improve the surface gloss of the steel strip in the above 3), it is necessary to continuously shift during rolling, so the shift amount is + -25 m.
A shift speed of 0.5 to 5 mm / sec is required in m.
Therefore, the device for moving the work roll by moving the roll chock by the hydraulic pressure generally used for 1) and 2) cannot be used as it is for the purpose of 3) above, and modification is required. For example, it is necessary to review the cylinder diameter, hydraulic oil pipe diameter, mechanical component strength, etc. Further, in order to obtain a constant glossiness, it is also necessary to provide a control means for keeping the ratio of the rolling speed and the shift speed constant. Furthermore, the use of shifters for 1) and 2) for surface gloss improvement must sacrifice the original goal of the work roll shifter to control the profile or flatness of the strip.

An object of the present invention is to provide a cold rolling mill which has a function of imparting shear deformation in the width direction to the surface of a steel strip to improve gloss and can coexist with a profile and a flatness control mechanism. .

[0008]

DISCLOSURE OF THE INVENTION The inventors of the present invention are keen to develop a rolling mill having both functions of work roll shift and profile for improving the surface gloss of a steel strip and work roll shift for flatness control. As a result of the examination, if a cam device is installed between the roll and the roll chock to realize the shift for improving the surface gloss of the steel strip, the means for moving the roll chock by the conventional hydraulic cylinder and shifting the roll should be left as it is. We obtained the finding that both can be used together. The present invention has been made on the basis of such knowledge, and the gist thereof is "the upper and lower work rolls supported slidably in the axial direction, and the upper and lower work rolls in the axial direction by the rotation of the work rolls are mutually And a cam device for continuously swinging in the opposite direction, and the cam device is provided between one end of the work roll body and the roll chock ". .

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below based on Examples.

FIG. 1 is a view showing an embodiment of a roll shift device used in a rolling mill of the present invention. FIG. 1 (a) is a sectional view of a cam device provided between one end of a roll body and a roll chock. , (B) are A-A 'arrow views of (a).

Reference numeral 7 is a steel strip, and a cam device 1 is provided between one end of the roll body 2 and the roll chock. The cam device is a cam 11 serving as a driving joint and a follower joint 10 fixed to the roll chock 4. It consists of Roll chock 4
A radial bearing 15 for rotatably supporting the roll shaft 9 is provided therein and is slidable in the axial direction. For example, this can be achieved by setting the fit between the inner ring of the radial bearing and the roll shaft so that it can slide, or by using a bearing that can slide between the inner ring and the outer ring as the radial bearing. In addition, the thrust bearing 5 fixed to the roll shaft 9,
The coil spring 6 is installed between the bearing and the chock, and the cam 11 and the dependent node 10 are always in contact with each other. The cam contact portion of the subordinate node 10 is the roller 1
2, it is possible to reduce driving energy loss due to friction and prevent seizure due to heat generation.

The cam may be directly formed on the roll side surface, or only the cam may be made of another material and fixed to the roll side surface or the roll shaft. FIG. 1 (b) is a plan view of the cam, in which 13 is a peak of a mountain, 11 is a slope, and 14 is a valley bottom.

FIG. 2 is a diagram showing a concavo-convex pattern of the cam. As an example, if the average diameter of the ring-shaped portion where the cam and the subordinate contact each other is 400 mm, the cam length is 1257 mm in one round, and unevenness of 5 cycles of a triangular wave with an inclination of 0.02 is provided. If so, the amplitude becomes 2.514 mm.

FIG. 3 is a view showing another mode of the cam device. In this cam device, a part of the roll shaft 9 beside the roll body is made large in diameter, and a groove 8 serving as a cam is provided on the surface of the large diameter shaft. The other end is fixed to the roll chock so that it always comes into contact with.
In this example, the coil spring shown in FIG. 1 for maintaining the contact between the cam and the roller of the subordinate node is unnecessary.

In the rolling mill of the present invention, the rolls provided with the above-described cam device are provided vertically opposite each other between the roll body and the roll chock, and the concavo-convex pattern of the cams provided on the upper roll is provided. And the concavo-convex pattern of the cam provided on the lower roll is reversed. Therefore, the upper and lower rolls shift in opposite axial directions. Also,
Such a rolling mill may be used as a reverse rolling mill with only one stand, or may be used as a tandem rolling mill by arranging several stands.

In the rolling mill having the above-described structure, the cam follows the subordinate node, and the roll periodically swings in the axial direction as the roll rotates. Therefore, the power required to swing the roll in the axial direction is supplied by the rotational force of the roll, and no special power source is required.

The effect of improving the luster of the surface of the steel strip can be obtained if there is an axial slip of several times the pitch of the irregularities of the roll-polished mesh in the contact surface between the steel strip and the roll, which is called a rolling bite.
The amplitude of the axial swing is several mm, which is sufficient, and it can be applied to a general cold rolling mill without any trouble.

The function of improving gloss is determined by the inclination angle of the cam and can be obtained by setting the ratio of the moving distance in the rotation direction of the roll surface to the moving distance in the axial direction to a constant value, for example, 0.02 or more. In order to prevent the meandering of the steel strip due to the rocking of the roll, it is preferable that the axial moving speeds of the upper and lower work rolls are always the same in the reverse direction. In a rolling mill driven by a single upper and lower motor via a pinion gear, symmetrical rocking can be easily generated from the center of the rolling mill width direction by setting the cam devices for the upper and lower rolls.

Although not shown, a conventional hydraulic roll shift device for flatness control is a mechanism for shifting rolls by moving the roll chock in the roll axial direction by hydraulic pressure, so that the present invention can be used as it is. It can be applied to rolling mills.

[0020]

EFFECT OF THE INVENTION The rolling mill of the present invention can be easily obtained only by modifying the rolls and roll chocks of the rolling mill having no work roll shift function, and the profile of the steel strip, the roll shift for controlling the flatness, and the roll. Even a rolling mill having various functions such as a cloth can be easily made into a rolling mill having a gloss improving function by merely modifying the roll and the roll chock without impairing those functions.

[Brief description of the drawings]

FIG. 1 is a roll shift device 1 used in a rolling mill of the present invention.
FIG. 3 is a view showing an embodiment, (a) is a cross-sectional view of a cam device provided between one end of a roll body and a roll chock,
(B) is a view on arrow AA 'of (a).

FIG. 2 is a diagram showing an uneven pattern of a cam.

FIG. 3 is a diagram showing another aspect of the cam device.

[Explanation of symbols]

 1 Cam Device 2 Roll Body 3 Subordinate Node 4 Roll Chock 5 Thrust Bearing 6 Roll Shaft 8 Groove 11 Cam (Driving Node) 12 Roller 15 Radial Bearing

Claims (1)

[Claims] 1. An upper and lower work rolls supported slidably in an axial direction, and a cam device for continuously swinging the upper and lower work rolls in the axial direction and in mutually opposite directions by the rotation of the work rolls. And a cam device is provided between one end of the work roll body and the roll chock.