JPS5853312A - Multistage cluster rolling mill - Google Patents

Abstract

PURPOSE:To reduce the generation of edge drops and to obtain products of good shapes by splitting the backup rolls of multistage cluster rolling mills, off-centering the split rolls and loading roll bending force upon the metal chocks of work rolls. CONSTITUTION:In multistage cluster rolling mills, backup rolls 4 are split to plural rolls in the direction intersecting orthogonally with 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 said split rolls. Work rolls 2 are supported by metal chocks 8, and are made freely movable in an axial direction via joints 2b. Crowned parts 2b are provided at both ends of the effective length of the rolls 2. Further, means 11 for loading roll bending forces are provided to metal chocks 8 for the work rolls. By such mechanisms the rolls 2 and intermediate rolls 3 are bent along the rolls 4, whereby the formation of medially high shapes to a material 1 to be rolled is obviated.

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 reduce plate thickness by a large amount in one rolling from the viewpoint of improving productivity and saving energy. Requirements are also becoming increasingly strict.

There is a multi-stage cluster rolling mill that makes cold rolling under high pressure possible. This multi-stage cluster rolling mill has the advantage that the diameter of the work rolls can be reduced, so even if the rolling load is small, it can perform high-reduction rolling with 6 rolls. It becomes larger and the shape of the rolled material becomes defective. For this reason, conventional cluster rolling mills employ the following shape control means. L'l] First, the reinforcing roll is divided into a plurality of parts in 11 directions intersecting the axial direction, and the axial center position of the divided rolls obtained is relatively changed, that is, the divided roll is extruded in a convex shape with respect to the work roll. Therefore, attempts have been made to use shape control means to obtain a flat rolled material by moving intermediate rolls and work rolls that are bent in the opposite direction due to the rolling load.

However, even if the shape control means described above is adopted, if the rolled material has a narrow width, 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 transmitted to the work roll (in addition, because the work roll has a small diameter, the end of the work roll protruding from the plate material is damaged by the contact surface pressure with the middle roll). There was a problem in that the thickness of the plate near the end of the plate suddenly decreased, resulting in a defective shape (edge drops and edge wafers).

The present invention addresses the above-mentioned problems by arranging 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 in a vertically symmetrical manner. In a multi-stage cluster rolling mill arranged in A multi-stage cluster rolling mill is provided with a means for supporting the work roll so as to be displaceable in the axial direction and applying a roll pending force to a metal chock for the work roll, the object of which is to: An object of the present invention is to provide an improved multi-stage cluster rolling mill that can produce products with good shapes.

Next, the multi-stage cluster rolling mill of the present invention will be described with reference to an embodiment shown in FIGS. 1 to 6. In FIG. 1, (1) is a rolled material, which is rolled while progressing in the direction of the arrow.

In addition, f2021 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 a pair of upper and lower intermediate rolls (3) that support each of the same work rolls (3). Supporting upper and lower reinforcing rolls, (5) are metal chocks of the same reinforcing roll (4), (6) are supporting frames of the same metal chocks (5), and (9) are the same supporting frames (6)
The lowering device (7) is a metal chock for the intermediate roll (3), and is arranged so that each pair of upper and lower intermediate rolls (3) can be displaced symmetrically with respect to a vertical plane passing through the axis of the upper and lower work rolls (21). Also, (8) is the work role (2
), OI is the housing, 01) is the hydraulic cylinder for applying the pending force to the work roll]2), and O2 is the hydraulic cylinder for lifting the reinforcing roll metal chock (5). Further, the reinforcing roll (4) is, as shown in FIG.
is divided into a plurality of parts in a direction perpendicular to the axial direction of the fixed shaft (5a), and the bearing of the divided roll is eccentric with respect to the fixed shaft (5a), and when an adjustment device (not shown) is operated, the division The position of the axis of rotation of the roll is changed for each divided roll, so that the crown of the reinforcing roll (4) as a whole can be adjusted (see Fig. 5). Further, the work roll (2) is supported by a metal chock (8) held within the housing 00), and is connected to a moving device (not shown) for the work roll (2) via a joint (2b). and is movable in the axial direction of the work roll (2). In addition, crown portions (2a) are provided at both ends of the effective length cutting force (barrel length) of the work roll (2), as shown in Figure 3, and the diameter of the end portions is slightly smaller. In this multi-stage cluster rolling mill, since the work roll (2) has a small diameter, the drive device of the rolling mill is connected to the intermediate roll (3).

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

In general, the cross-sectional shape of the rolled material fil is affected 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. Furthermore, since the wear and tear of the rolls appears as a comprehensive result, the more shape control means there are, the more detailed the shape control becomes possible.

Figure 4 (a) shows the contact pressure distribution between the rolls when the ratio Bit to the roll length (barrel length) C of Tadashi Iiyama is 1.0, and Figure 4 (b) shows the distribution of contact pressure between the rolls (plate 1). Roll length of Bl (t
) shows the inter-roll contact surface pressure distribution when the ratio Bit is 0.5. Since the amount of roll flattening is approximately proportional to the inter-roll contact surface pressure, Figure 4 (Iiyama If (B) is smaller than the roll length + 7 = 1, it is necessary to take corrective measures against the increase in the crown of the rolled material due to roll flattening. The part of the roll that protrudes from the edge of the plate, and the contact surface pressure between the rolls that occurs there is to bend the work roll with a small diameter in the direction of the rolled material and press the edge of the plate, and to press the edge of the plate, and to press the workpiece that comes into contact with the rolled material. Due to the uneven flatness of the roll surface, edge drops, where the thickness of the sheet suddenly decreases, occur at the ends of the cross section of the sheet.

However, the present invention is configured as described above, and the reinforcing roll (41) is pushed out in a convex shape with respect to the work roll (2), and the work roll (2) and intermediate roll (3) are rolled by a rolling cart. ), but if the width of the rolled material (1) is narrow, the convex shape of the auxiliary roll (4) cannot be sufficiently transmitted to the rolled material (1), so the pending force is applied to the work roll (2). is applied, and the work roll (2) and intermediate roll (3) are bent along the auxiliary roll (4) to prevent the rolled material (1) from forming a mid-height shape. A crown part (2a) provided at one end of the work roll (2) is provided at one end of the rolled material (1), and a crown part (2a) provided at the other end of the lower work roll (2) is provided at one end of the rolled material (1).
2a) are brought into contact with the other ends of the rolled material (1), and the crowns of the upper and lower work rolls (2) are brought into contact with the straight bodies of the upper and lower intermediate rolls (3), so that the work rolls (2) and the plate are brought into contact with each other. Since the contact pressure with the edge can be reduced, edge drop can be reduced and a product with a good shape can be obtained.

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. .

[Brief explanation of the drawing]

Fig. 1 is a side view showing an embodiment of a multi-stage cluster rolling mill according to the present invention, Fig. 2 is a front view thereof, Fig. 6 is a front view showing work rolls, and Fig. 4 shows contact surface pressure between rolls. FIG. 5 is an explanatory view showing the crown alAI adjustment state of the reinforcing roll, and FIG. 6 is an explanatory view showing the operation when rolling is performed by moving the work roll in the axial direction. +1)--1 rolled material, +21-m-work roll, (3
)-m-middle roll, 141--one reinforcing roll, +81
---Metal chock for work rolls, En-11 roll bending force loading means.

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 reinforcement At least two of the upper and lower rolls are divided eccentric rolls so that the crowns can be adjusted, crowning is formed at both ends of the effective roll length of the work roll, and the work roll is supported so as to be displaceable in the axial direction. A multi-stage cluster rolling mill characterized in that the metal chock for the work rolls is provided with a means for applying a rolling force to the rolls.