JPH0616884B2 - Multi-stage rolling mill - Google Patents

Description

The present invention relates to a multi-stage rolling mill having a plurality of reinforcing rolls.

<Prior Art> In recent years, in the rolling field, from the viewpoint of improving productivity and energy saving, there has been a demand for a high pressure rolling mill capable of significantly reducing the plate thickness in one rolling step. On the other hand, there is also a strong demand for a rolling mill that can freely change the shape of the rolled sheet according to the purpose of use. As a rolling mill capable of rolling under the above high pressure, a multi-stage cluster type that can reduce the work roll diameter to a high pressure has been developed, and in this type, the control of the plate shape can be freely changed according to the purpose of use, Moreover, the multi-stage cluster rolling mill shown in FIG. 3 is provided with a mechanism capable of easily performing the operation during rolling.

This multi-stage cluster rolling mill has a pair of upper and lower work rolls 1.
And two upper and lower intermediate rolls 2 for supporting the work rolls 1, and a plurality of reinforcing rolls 3a and 3b for vertically pressing the work rolls, which are divided into five along the axial direction and are arranged symmetrically in the vertical direction. In the rolling mill, the reinforcing rolls 3a excluding the reinforcing rolls 3b at both ends of the reinforcing rolls
Are rotatably mounted on eccentric sleeps 5 attached to the reinforcing roll supporting shafts 4, respectively, and a frame for supporting the reinforcing roll supporting shafts 4 including a sector gear 6, a rack bar 7, and a hydraulic actuator 8 for rotating the eccentric sleeps 5. 9
It was installed in. Reference numeral 10 in the figure denotes a roll movement amount detector, and the eccentric sleeve 5 has a needle roller interposed between the outer ring and the inner ring.

In this multi-stage cluster rolling mill, since the work roll 1 can be downsized, there are advantages such as a small rolling load and high pressure. When the work roll 1 is bent and deformed, the hydraulic actuator 8 is driven to rotate the eccentric sleeve 5 via the sector gear 6 and the rack bar 7, and the reinforcing roll 3a is eccentrically deformed. There is also an advantage that can be offset.

Now, let us consider the load applied to the reinforcing rolls 3a and 3b during rolling. Figure 4 shows the linear pressure (load) acting on each reinforcing roll in the case of a rolled material with a relatively wide strip.
The outline of is shown. Assuming that the rolling pressure between the rolled material and the work roll 1 is evenly distributed, if the rolling pressure acts on the reinforcing rolls 3a and 3b through the intermediate roll 2, as shown in FIG. 4 (b). , The load is applied most to the central reinforcing rolls 3a, and then to the reinforcing rolls 3 on both sides thereof.
The load applied to a is increased, and the load applied to the reinforcing rolls 3b on both sides is the smallest. This inevitably occurs due to the bending rigidity of the reinforcing roll support shaft 4, and this tendency becomes more remarkable as the plate thickness of the rolled material decreases.
In addition, the same rolling bearing is usually used for the reinforcing rolls 3a and 3b in terms of compatibility.

<Problems to be Solved by the Invention> In the above-described multi-stage cluster rolling mill, the bearings supporting the reinforcing rolls 3a and 3b are the same, even though the largest load is applied to the central reinforcing roll 3a. Therefore, the bearing life of the central reinforcing roll 3a is the shortest. Therefore, the maximum rolling load of this multi-stage cluster rolling mill becomes relatively small because it is set based on the central reinforcing roll 3a.

The present invention has been made in order to effectively solve this drawback, and an object of the present invention is to provide a multi-stage rolling mill equipped with a mechanism for changing the plate shape and capable of performing high-pressure rolling.

<Means and Actions for Solving Problems> The structure of the present invention for achieving the above-mentioned object includes a pair of upper and lower work rolls, a plurality of work rolls arranged along the axial direction, and a plurality of work rolls arranged vertically. In a multi-stage rolling mill having a reinforcing roll that presses the work roll via an intermediate roll, among the divided reinforcing rolls, a reinforcing roll that receives a large load during rolling is made eccentric, and another reinforcing roll is supported. It is characterized in that it is mounted eccentrically to the shaft, and the bearing strength of the reinforcing roll that cannot be eccentric is increased, and the allowable rolling load of the reinforcing roll at the position where the maximum load is applied is increased.

<Example> FIG. 1 (a) has a cross section along the axial direction of a reinforcing roll (back up roll) of a multi-stage cluster rolling mill according to an embodiment of the present invention, and FIG. 1 (b) shows 1 (a) shows the details of the reinforcing roll in the center, FIG. 1 (c) shows the details of the reinforcing rolls other than the center in FIG. 1 (a), and FIG. 1 (d) shows the details. The arrow A view in FIG. 1 (c) is shown. In these drawings, only the upper reinforcing roll is shown.

In the figure, 11a and 11b are reinforcing rolls that reinforce the intermediate roll and the work roll (not shown), and are divided into five along a direction parallel to the axial direction. Reinforcing rolls 11a, 11
The support shaft 12 of b is strongly attached to the frame 13, and an eccentric sleeve 14 is fixedly fitted to the central portion of the support shaft 12 and both sides of the eccentric sleeve 14 are 2
An eccentric sleeve 15 is rotatably fitted to the position, and a reinforcing roll 11a is attached to the eccentric sleeve 14 and an eccentric sleeve 15 is provided.
Reinforcing rolls 11b are rotatably fitted in each of them. That is, the center of the reinforcing roll 11b is deviated from the center of the support shaft 12, and if the eccentric sleeve 15 rotates between the support shaft 12 and the reinforcing roll 11b, the center position of the reinforcing roll 11b also changes. is there. A special rolling bearing consisting of rollers 16 and an inner ring 17 is incorporated between the eccentric sleeve 14 and the reinforcing roll 11a, and between the eccentric sleeve 15 and the reinforcing roll 11b.
Inner ring 1 and roller 18 having a roller length and diameter smaller than roller 16
A special rolling bearing consisting of 9 and 9 is incorporated.
In the figure, 17a and 19a are oil seals. A lever 21 having a sector gear 20 formed at its end is integrally connected to the rotatable eccentric sleeve 15. Two rack bars 22 are installed in the frame 13 above the respective reinforcing rolls 11b (below the lower reinforcing rolls) in parallel with the rolling direction so as to be movable in the axial direction thereof, and the lower surface thereof. The sector gear 20 of the lever 21, which is integral with the eccentric sleeve 15 to which the reinforcing rolls 11b before and after the rolling direction are fitted, is meshed with the rack formed in FIG. Racks are also formed on the facing surfaces of the two levers 21, respectively, and pinions (not shown) are supported by the frame 13 so as to engage with the racks, and a hydraulic actuator 23 is connected to the pinions. That is, the pinion (not shown) is rotated by the drive of the hydraulic actuator 23, whereby the two rack bars 22 are moved in the opposite directions, whereby the levers 21 and the respective gears 21 meshed with the racks of the rack bars 22 by the sector gear 20. The eccentric sleeve 15 integrated with this rotates equally in the opposite direction, whereby the center of the reinforcing roll 11b is displaced, and the rolling force acting on the intermediate roll and the work roll is changed. The eccentric sleeve 14 serves as a reference for the variable eccentric sleeve 15 and is fixed at a fixed position.

In the figure, 24 is a needle bearing, which is an eccentric sleeve 15.
Is installed so that it can rotate lightly even during rolling under high pressure.

In addition, as an eccentric method of the reinforcing roll 11b, as shown in FIG.
The eccentric sleeve 25 may be provided directly on the support shaft 12 as shown in FIG. 5, or the inner ring of the bearing may be directly provided on the support shaft 26 by using the eccentric stepped support shaft 26 as shown in FIG.

In the multi-stage cluster rolling machine configured as described above, the position of the reinforcing rolls 11b, that is, the crowns of the intermediate rolls and the work rolls can be changed by rotating the eccentric sleeve 15. Can be finished into a flat material with a good flat shape.

Generally, the basic dynamic load rating C of rolling bearing is C = fe (i
· Leff · _cos α) ^7/9 × Z ^3/4 × Da ^29/27 (1)

In the formula, fe: coefficient of radial roller bearing, α: nominal contact angle, i: number of rows of rolling elements in one bearing, Z: number of rolling elements included in one row, Da: diameter of rolling element, leff : Effective length of rolling element.

Here, comparing the bearings used for the reinforcing rolls 11a and 11b, the central reinforcing roll 11a is not eccentric, so that the roll width is smaller than that of the reinforcing roll 11b by the width of the lever 21. It is widening. Since the fixed eccentric sleeve 14 is used for the reinforcing roll 11a, the inner ring 17 of the bearing has a smaller diameter than the inner ring 19 of the bearing of the reinforcing roll 11b. As a result, the roller length and diameter of the roller 16 of the bearing of the reinforcing roll 11a are larger than that of the roller 18 of the bearing of the reinforcing roll 11b. Therefore, as can be seen from the equation (1), the basic dynamic load rating of the bearing is larger in the bearing of the reinforcing roll 11a and the rigidity is also higher.

That is, the reinforcing roll 11a in the central portion where the load is relatively large
Since the bearing rigidity of is high, rolling under high pressure is possible.

Although the above-described one embodiment is applied to the multi-stage cluster type rolling mill, it can be applied to various multi-stage rolling mills as long as the reinforcing rolls for applying a pressing force to the work rolls are divided into a plurality of rolling mills.

<Effects of the Invention> In the present invention, among the divided reinforcing rolls, the reinforcing roll that receives a large load at the time of rolling is made eccentric so that the rigidity of the bearing is increased, and another reinforcing roll that receives a relatively small load is inserted through the eccentric sleeve. Since the eccentricity is possible, the maximum rolling load can be improved without changing the housing and the chuck size, and the work roll crown can be adjusted by eccentricizing the reinforcing roll with a small driving force.

[Brief description of drawings]

FIG. 1 (a) is a cross-sectional view along the axial direction of a reinforcing roll (back up roll) of a multi-stage cluster rolling mill according to an embodiment of the present invention, and FIG. 1 (b) is a center in FIG. 1 (a). FIG. 1 (c) is a detailed view of the reinforcing rolls other than the center in FIG. 1 (a), FIG. 1 (d) is a view taken in the direction of arrow A in FIG. 1 (c), Fig. 2
(a) is a sectional view of a reinforcing roll having an eccentric sleeve directly attached to a support shaft, FIG. 2 (b) is a sectional view of a supporting shaft having an eccentric stepped support shaft, and FIG. 3 (a) is a multistage Fig. 3 (b) is a schematic view of a cluster rolling mill, Fig. 3 (b) is a sectional view taken along the axial direction of the reinforcing roll, Fig. 4 (a) is a diagram showing an outline of linear pressure acting on the reinforcing roll, and Fig. 4 (b). ) Is a distribution diagram of linear pressure acting on the reinforcing roll. In the drawings, 11a and 11b are reinforcing rolls, 12 is a support shaft, 13 is a frame, 15 is an eccentric sleeve, 16 and 18 are rollers, 21 is a lever, and 22 is a rack bar.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koichi Ikariishi 1 Kawasaki-cho, Chiba City, Chiba Prefecture Inside the Kawasaki Steel Co., Ltd. (72) Inventor Makoto Suzuki 1 Kawasaki-cho, Chiba City Chiba Prefecture Kawasaki Steel Co., Ltd. Chiba Inside the steel mill

Claims (1)

[Claims] 1. A multi-stage rolling mill having a pair of upper and lower work rolls, and a plurality of reinforcing rolls which are divided into a plurality of work rolls in the axial direction and are arranged above and below to press the work rolls via intermediate rolls. A multi-stage rolling mill characterized in that, of the divided reinforcing rolls, a reinforcing roll that receives a large load during rolling is made eccentric and another reinforcing roll is eccentrically attached to a supporting roll supporting shaft.