JPS5853308A - Multistage cluster rolling mill - Google Patents

Abstract

PURPOSE:To prevent the generation of edge drops, etc. and to obtain products of good shapes by forming split type eccentric rolls for the backup rolls of multistage rolling mills and loading roll bending force upon the metal chocks of intermediate rolls. CONSTITUTION:In multistage cluster rolling mills, backup rolls 4 are split to plural rolls in the direction intersecting orthogonally the axial direction of stationary shafts 5a and the bearings of the split rolls are off-centered. Crowns are adjusted by the entire part of the rolls 4. Crowned parts are provided in the end parts of upper and lower work rolls and intermediate rolls 3 and are moved symmetrically in an axial direction. Further, means 11, 12 for loading roll bending force are provided to metal chocks 7 for the intermediate rolls to transmit the rugged shapes formed by the backup rolls effectively to the work rolls 2. By such mechanism the products having less generation of edge drops, etc. are obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in multi-stage cluster rolling mills.

In recent years, there has been a demand for high-reduction rolling mills that can significantly reduce plate width and thickness in a single rolling process in order to improve productivity and save energy. Requirements are also becoming increasingly strict.

There is a multi-stage cluster rolling mill that enables cold rolling under high pressure. This multi-stage cluster rolling mill has the advantage of being able to reduce the diameter of the work rolls, allowing high reduction rolling even when the rolling load is small. (As a result, the shape of the rolled material becomes defective. Therefore, in conventional cluster rolling mills, the following shape control means are adopted. Namely, the reinforcing roll is divided into a plurality of parts in the direction perpendicular to the axial direction. By changing the axial center position of the divided rolls relative to each other, that is, by extruding the divided rolls in a convex shape with respect to the work rolls,
A shape control means is employed that attempts to obtain a flat rolled material by deflecting intermediate rolls and work rolls that are deflected by the rolling load in the opposite direction.

However, even if the above-mentioned shape control means is adopted, if the Iiyama of the rolling system is narrow, most of the rolling load will be applied to the center of the roll, making it difficult for the intermediate roll and work roll to bend along the reinforcing roll. The crown adjustment effect of the reinforcing roll is not easily transmitted to the work roll. Moreover, because the work roll has a small diameter, the end of the work roll that protrudes from the plate material is bent toward the plate material due to the contact surface pressure with the intermediate roll, and the thickness of the work roll near the edge of the plate material decreases rapidly. As a result, there is a problem that the shape becomes defective (edge drops and edge waves occur).

The present invention addresses the above-mentioned problems, and includes a work roll, a set of two intermediate rolls that support the work roll, and a plurality of auxiliary rolls that support each of the intermediate rolls, which are vertically symmetrically arranged. In the multi-stage cluster rolling mill, at least two upper and lower reinforcing rolls are divided eccentric rolls so that crowns can be adjusted, and the work roll and the intermediate roll are supported so as to be displaceable in the axial direction. Then! = 4 relates to a multi-stage cluster rolling mill characterized in that a means for applying a roll pending force to a metal chock for intermediate rolls is provided, and its purpose is to improve the ability to obtain products with good shape. The main feature is that it provides a multi-stage cluster rolling mill.

Next, the multi-stage cluster rolling mill of the present invention will be explained using an embodiment shown in FIGS. 1 to 7. +11 in FIG. 1 is a rolled material, which is rolled while progressing in the direction of the arrow.

12)+21 is a pair of upper and lower work rolls, (3) is a pair of upper and lower intermediate rolls that support each of the work rolls (2), and (4) is 6 of each of the same intermediate rolls (3). (5) is the metal chock of each reinforcing roll (4), (6) is the support frame of the metal chock (5), and (9) is the support frame (6) of the same metal chock (5).
), in which (7) is a metal chock for the intermediate roll (3), each pair of upper and lower intermediate rolls (3) is displaced symmetrically with respect to a vertical plane passing through the axes of the upper and lower work rolls (2). It's getting wet. Also, (8) is work roll 1
2) metal chock, 00) is the housing, Oυ(1
2 is a hydraulic cylinder for loading the roll loading force onto the intermediate roll (3), and 2 is a hydraulic cylinder for lifting the reinforcing roll metal chock (5). Further, as shown in Fig. 2, the reinforcing roll (4) is divided into several parts in a direction perpendicular to the axial direction of the fixed shaft (5a) of the reinforcing roll (4), and the bearings of the divided rolls are fixed. shaft(
5a), and when the adjusting device (shown in the figure) is operated, the rotation axis position of the divided rolls is changed one by one, and the reinforcing roll (4) as a whole is adjusted to the crown position. is now being adjusted. Further, the work roll (2) and the intermediate roll (3) are held in the housing 0■ and metal chocks (8) and (7).
), and is connected to a moving device jli (not shown) for the work roll 12) via a joint (2bX3b), and moves one of the rolls in the axial direction of the work roll (2).
Each one is movable. In addition, at both ends of the effective length 4 (barrel length) of the work roll (2) and intermediate roll (3), there are crown parts (2a) (3a) as shown in Fig. 4.
, and the diameter of the end is slightly smaller. In addition, in this multi-stage cluster rolling mill, since the work roll (2) has a small diameter, the driving device of the rolling mill is connected to the intermediate roll (3).
is connected to.

Next, the operation of the multi-stage cluster rolling mill will be explained.

In general, the cross-sectional shape of the rolled material (1) is determined not only by the elastic deflection of the rolls, but also by uneven flatness of the roll contact area due to uneven contact pressure between the rolls and uneven temperature of each part of the rolls. Since the wear of the crown, and even the rolls, etc. appear as a combined result, the more shape control means there are, the more finely the shape control becomes possible.

Figure 5 (a) shows the roll length (barrel length) of Iiyama (B) (
Figure 5 (b) shows the contact surface pressure distribution between rolls when the ratio Bit to 4 is 1.0, and Figure 5 (b) shows the contact surface pressure distribution between rolls when the ratio B/l to the force is 0.5. These graphs show the surface pressure distribution. Since the amount of roll flattening is approximately proportional to the contact surface pressure between rolls, as shown in Figure 5 (b), Iiyama (B) In this case, it is necessary to take corrective measures against the increase in the crown of the rolled material due to the flattening of the rolls.

Figure 6 (a) shows a situation in which edge drop occurs, where the inter-roll contact surface pressure that occurs in the part of the work roll and the intermediate roll that protrudes from the plate edge is lower than that of the work roll with a small diameter. By bending the base in the direction of the rolled material and pushing the root end, and by making the flatness of the work roll surface in contact with the rolled material uneven, the end of the plate cross section is bent as shown in Figure 6(b). An edge drop occurs where the plate thickness suddenly decreases (μ.

reference).

However, the present invention is configured as described above, and the arbitrary convex shape formed by the reinforcing roll (4) is
3) By loading the K-roll bending force, it can be effectively transmitted to the work roll (2), and by moving the one-sided intermediate roll (3) in opposite directions according to Iiyama, the intermediate The harmful restraint of the work roll (2) by the roll (31) can be removed, and as a result, the deformation of the work roll (2) in the Iiyama direction due to the rolling load is made uniform, and the mid-high crown that occurs in the rolled material (1) is eliminated. Also, due to the axial movement of the intermediate roll (3), local flattening of the work roll (2) occurs at the end of the intermediate roll (3), and the end of the work roll (2) The rolling load deforms the plate into a more convex shape, reducing edge drop.

Figure 7 shows the upper and lower intermediate rolls (3) and the work roll (
2) is moved in the axial direction according to Iiyama, and in the opposite direction vertically. That is, in this case, the crown part provided at one end of the upper work roll (2) is connected to the rolled material (1).
), the crown portion provided at the other end of the lower work roll (2) is brought into contact with the other end of the rolled material (1), and the upper and lower intermediate rolls (3) are attached to the crown portions of the upper and lower work rolls (2). The straight body of the roller is in contact with the intermediate roll (
The harmful restraint of the work roll (2) caused by 3) can be almost completely removed, and the deformation of the work roll (2) can be made uniform. Therefore, the shape control ability can be greatly improved, but in addition to this method, a pending load is also applied to the intermediate roll (3), which prevents the occurrence of medium and high crowns and edge drops in the rolled material ('11), and lfJ. (μ2) in Fig. 6 is the intermediate roll (3
) and applying a roll pending force (plate thickness accuracy in 81 directions, (μ3) is the intermediate roll (3)
This is the plate thickness accuracy in the plate rlJ (B) direction when the work roll (2) is shifted, a roll pending force is applied, and the work roll (2) is further shifted.

Although the present invention has been described above with reference to embodiments, it goes without saying that the present invention is not limited to such embodiments, and that various design modifications can be made without departing from the spirit of the present invention. . For example, in the embodiment described above, a six-high cluster rolling mill has been described, but the present invention can also be applied to a multi-stage cluster rolling mill in which an appropriate number of second intermediate rolls and sixth intermediate rolls are arranged between the reinforcing roll and the intermediate roll.

[Brief explanation of drawings]

Fig. 1 is a side view showing a multi-stage cluster rolling mill according to the present invention, Fig. 2 is a front view thereof, Fig. 3 is an explanatory view showing the crown adjustment state of the reinforcing roll, and Fig. 4 is a diagram showing the work roll and intermediate roll. FIG. 5 is an explanatory diagram showing the contact surface pressure between rolls, FIG. 6 is an explanatory diagram showing the effect of the present invention, and FIG. 7 is an illustration of rolling by moving the intermediate roll and work roll in the axial direction. FIG. fll--1 rolled material, f2)---work roll, (3
)-m-middle roll, +41--one reinforcing roll, (71
---Metal chock for intermediate roll, r-(11H12
1--One roll pending force loading means. Sub-Agent Patent Attorney Shigefumi Okamoto and 2 others Figure 3

Claims (1)

[Claims] In a multi-stage cluster rolling mill in which a work roll, a set of two intermediate rolls that support the work roll, and a plurality of auxiliary rolls that support each of the intermediate rolls are arranged vertically symmetrically, the reinforcing roll At least two upper and lower rolls each are split type eccentric rolls so that the crowns can be adjusted, and the work roll and the intermediate roll are supported so as to be displaceable in the axial direction, and a roll pending force is applied to the metal chock for the intermediate roll. A multi-cluster rolling mill characterized in that it is provided with means for.