JPS6323842B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cross-roll rolling mill that eliminates the adverse effects of thrust force acting on the rolls.

In recent years, a method has been developed to control the thickness distribution of rolled products in the width direction by rolling the material by crossing upper and lower work rolls and back-up rolls, and a cross-roll rolling mill that realizes this method has been developed. Various methods have also been proposed.

In a cross-roll type rolling mill, rolling is performed by crossing the upper and lower roll groups at a required cross angle θ, so as shown in Fig. 1, the upper work roll 02
Since the circumferential speed direction V _R and the traveling direction V _S of the rolled material 01 differ by an amount equivalent to the cross angle θ, slippage occurs in the axial direction V _T and a thrust force acts on the upper work roll 02. Similarly, thrust forces of equal magnitude and opposite direction act on the lower work roll 03.

Comparing this thrust force with a conventional rolling mill, in which the upper and lower roll groups are parallel and the cross angle θ is 0, it is found that the conventional work roll has a cross angle θ
Since V T is 0, theoretically there is no slippage in the axial direction V _T and no thrust force is generated, but in actual rolling, a slight thrust force T is generated, and its value is about 1 to 5% of the rolling force P. It is. Therefore, the frictional force F in the direction of the rolling force due to the thrust force T is so small that it can be ignored.

This frictional force F is given by the following equation (1), assuming that the friction coefficient μ _S of the sliding portions in the rolling direction of the roll chock that supports the work roll is sliding friction, and μ _S =0.1 to 0.2.

F=μ _S・T = (0.001 to 0.003) P ...(1) Since it is sliding friction, the friction coefficient μ _S is large, but since the thrust force T is small, the friction force F is also small, and the hysteresis of the rolling force is also small. It is small and does not affect plate thickness control in any way and poses no problem.

On the other hand, in a cross-roll type rolling mill, the thrust force T is large and its value is about 4 to 5% of the rolling force P. This cannot be ignored, and if the roll chock is supported via a sliding part, a large thrust force The frictional force F is also large due to the force T and the sliding friction coefficient μ _S , and this frictional force F affects the rolling force when the roll is moved in the rolling force direction, increasing the hysteresis. This affects the A, G, and C plate thickness control, making it difficult to improve accuracy. Therefore, in order to improve the effect of this thrust force, it has been proposed to install wheels before and after the rolling direction of the roll chock to create rolling friction, but this is not sufficient, and in order to cross the rolls, the two wheels are parallel to the rolling direction. However, there are drawbacks such as relative displacement occurring and uneven thrust force acting on each wheel.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate such conventional drawbacks, eliminate the influence of thrust force in the direction of rolling force, and provide a cross-roll rolling mill that can support thrust force equally in the front and back of the rolling direction. The configuration of the present invention that achieves this object is to move the central axis of each roll in a horizontal plane with respect to the direction perpendicular to the rolling direction by displacing the roll yoke that supports the upper and lower work rolls and the back-up rolls back and forth in the rolling direction. In a cross-roll type rolling mill that is tilted at a tilt angle, a central part of a support arm extending forward and backward in the rolling direction is attached to the outer end of the roll chock so as to be rotatable in a horizontal plane, and wheels are attached to both ends of the support arm for rotation. The housing is characterized in that these wheels are rotatably mounted in guide grooves formed along the direction of the rolling force of the housing.

Hereinafter, one embodiment of the present invention will be described in detail based on the drawings.

2 to 5 show an embodiment of the cross-roll rolling mill of the present invention, in which FIG. 2 is a plan view of the work roll, FIG. 3 is an enlarged plan view of the main part, and FIG. A sectional view taken along the - line in the figure, Figure 5 is the 3rd
It is a - arrow direction view in a figure.

In order to support the work roll 1, a chock liner 3 having an arcuate surface protruding outward in the rolling direction is attached to each of the roll chock 2 provided at both ends thereof, and a pusher guide 5 is attached to the housing 4 so as to come into contact with the chock liner 3. A pusher bar 6 is provided which reciprocates while being guided by. This pusher bar 6 gives the work roll 1 a cross angle θ in a horizontal plane with respect to a direction perpendicular to the rolling direction, and is connected to a worm jack 7 attached to the housing 4 at the rear end of the pusher bar 6 for reciprocating motion. The cross angle θ is set by controlling the position of the pusher bar 6. In this case, the pusher bars 6 provided before and after the rolling direction move in the opposite direction by the same amount of movement, and are held in a state where they clamp the chop liner 3.

On the other hand, the thrust force T acting on the work roll 1
In order to support the thrust force, the roll chock 2 on the side where the thrust force acts
Support parts 2a, 2b are formed in two stages, upper and lower, protruding outward at the outer end of the support parts 2a, 2b.
A support arm 8 is inserted between the support arms 2b, and the center portion of the support arm 8 is attached via a bush 12 with a pin joint 11 located in the vertical direction so as to be rotatable in a horizontal plane. Wheels 10 are attached to both ends of the support arm 8 in the rolling direction at symmetrical positions with respect to the pin joint 11 via self-aligning rolling bearings 9. The wheels 10 each have an L-shaped clamp plate whose base end is rotatably attached to the outer surface of a pusher guide 5 attached to the housing 4 and the pusher guide 5 with a pin, and whose tip is parallel to the pusher guide 5. It is mounted in a guide groove 15 extending in the direction of the rolling force formed by the inner surface of the roller 13 and is capable of rolling. This guide groove 15
As shown in FIG. 2, the clamp plate 13 forming the work roll 1 is opened and closed by a hydraulic cylinder 14 whose base end is attached to the housing 4, so that the work roll 1 can be easily rearranged.

With this configuration, the thrust force T acting on the work roll 1 is transmitted from the support parts 2a, 2b of the roll chock 2 to the support arm 8 via the pin joint 11, and is further transmitted to the wheels at both ends of the support arm 8. 10 and is supported by a clamp plate 13 forming a guide groove 15 attached to the housing 4.

Since the roll chock 2 is supported via the wheels 10 in this way, its frictional state becomes rolling friction, and the frictional force F in the direction of the rolling force is the rolling friction coefficient μ _R
The rolling friction coefficient μ _R is the sliding friction coefficient μ _S of the conventional sliding part.
(=0.1~0.2), and its value is μ _R =
It is about 0.005 to 0.01, and even if the thrust force T is as large as 4 to 5% of the rolling force P, the friction force F is small as given by the following equation (2).

F=μ _R・T = (0.0002 to 0.0005) P ...(2) Therefore, the friction force F generated by the thrust force T is smaller than the friction force of sliding friction shown by the conventional formula (1). It has little effect on the hysteresis of rolling force and does not affect plate thickness control.

In addition, the thrust force T transmitted to the roll chock 2 is supported by a rotatable support arm 8 via a pin joint 11 and wheels 10 attached to both ends of this support arm 8 via self-aligning rolling bearings 9. When the cross angle θ is applied to the work roll 1 by the pusher bar 6, the roll chock 2 moves in an arc, resulting in a relative displacement in the roll axis direction on both sides of the work roll 1 in the rolling direction of the roll chock 2, that is, on both sides of the work roll 1 in FIG. However, since the wheels 10 are always kept parallel to the clamp plate 13 of the housing 4 by the support arm 8 and the self-aligning rolling bearing 9, the thrust forces on the left and right wheels 10 are equalized and balanced. Ru.

In the above embodiment, the work roll was explained among the roll groups, but a backup roll may be configured in the same way, and it goes without saying that the work roll that is paired with the illustrated work roll is provided at the opposite end. stomach. Moreover, although a self-aligning type rolling bearing is preferable as the rolling bearing to which the wheel 10 is attached, a general rolling bearing can also be used.

As specifically explained above in conjunction with the embodiments, according to the present invention, even in a cross-roll type rolling mill, it is possible to reduce the frictional force in the rolling force direction due to the thrust force acting on the rolls, and the frictional force in the rolling force direction can be reduced. The hysteresis that affects the rolling force during roll movement is reduced, so AGC plate thickness control is not adversely affected and plate thickness can be controlled with high precision. In addition, the thrust force acting on the rolls can be evenly supported in the front and back of the rolling direction, so that no unreasonable force is applied to the rolling bearings that support the wheels, extending the life of the bearings.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the thrust force acting on the rolls of a cross-roll rolling mill, and FIGS. 2 to 5 show an embodiment of the cross-roll rolling mill of the present invention.
Fig. 2 is a plan view of the work roll portion, Fig. 3 is an enlarged plan view of the main part, Fig. 4 is a sectional view taken along the - line in Fig. 3, and Fig. 5 is a - arrow view in Fig. 3. It is a diagram. In the drawings, 1 is a work roll, 2 is a roll chock, 2a, 2b are support parts, 4 is a housing, 5 is a pusher guide, 6 is a pusher bar, 8 is a support arm, 9 is a self-aligning rolling bearing, 10 is a wheel, 1
1 is pin joint, 13 is clamp plate,
15 is a guide groove.

Claims (1)

[Claims] 1. A cross-roll rolling mill in which the central axis of each roll is tilted in a horizontal plane with respect to the direction perpendicular to the rolling direction by displacing the roll jocks that support the upper and lower work rolls and back-up rolls back and forth in the rolling direction. At this time, the center portion of a support arm extending forward and backward in the rolling direction is rotatably attached to the outer end of the roll chock in a horizontal plane, and wheels are rotatably attached to both ends of the support arm, while these wheels are attached to the lower end of the housing. A cross-roll rolling mill characterized in that the rolling mill is rotatably mounted in a guide groove formed along the direction of force.