JPH03230802A - rolling mill - Google Patents

Abstract

PURPOSE:To control roll crown in accordance with the movement of roll by forming the max. diameter part of roll crown asymmetrically to the center line in the longitudinal direction of roll and further constituting the rolls movably in the axial direction. CONSTITUTION:The roll crowns 1a, 2a of upper and lower rolls 1, 2 are formed so that the whole of roll barrels are made into convex shape and also its max. diameter parts 1c, 2c are asymmetrically formed to the center line by situating so as to be respectively shifted in the axial direction to the center in the longitudinal direction of the upper and lower rolls 1, 2. Further, the upper and lower rolls 1, 2 are constituted movably in the axial direction. Therefore, it is enough to possess the rolls with only one kind of crown instaed of that the rolls with various crowns must be possessed and roll crown can be controlled in accordance with the movement of roll.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rolling mill in which what corresponds to the initial crown of a roll can be freely changed.

[Conventional technology]

Requirements for plate thickness accuracy of rolled products are becoming stricter year by year. Among plate thickness accuracy, the longitudinal direction is at a stage where it can be fully satisfied due to advances in automatic plate thickness control, hydraulic reduction equipment, and measurement technology, but in the width direction, there is no effective control method. The main reason is that the current situation is that it cannot be controlled at will.

Of course, a roll bending device is used as a means to modify the sheet thickness distribution in the width direction of the sheet, and has achieved certain effects, but this alone is insufficient in its ability, and in cases where the material width has to be changed significantly, Situations that could not be fully controlled often occurred.

[Problem that the invention seeks to solve]

Therefore, in conventional rolling mills, in order to compensate for the drawbacks of such bending devices, as is well known, the rolls are previously provided with an initial crown. However, the initial crown given to the roll is, of course, fixed and cannot be changed freely. For this reason, each rolling operation must be replaced with a roll that has the optimal initial crown, and if there are many types of work, it is necessary to have a variety of rolls with appropriate initial crowns. It had extremely large drawbacks in terms of workability and running costs.

The object of the present invention is to eliminate the drawbacks of the prior art, and to provide controllability that allows the amount corresponding to the roll initial crown to be changed arbitrarily and to control the roll crown according to each direction of movement of the roll. This provides an excellent rolling mill.

[Means for solving problems]

The problem is that in a rolling mill in which a pair of rolls forming a roll crown whose curvature changes over the entire length of the roll barrel is arranged point-symmetrically with respect to the center of the rolling mill, the roll crown is The entire roll barrel is formed to have a convex shape, and the maximum diameter portion thereof is positioned axially offset from the longitudinal center of the roll, so that it is formed in a left-right asymmetric shape, and furthermore, This problem is solved by making the roll movable in the axial direction.

[Effect]

According to the configuration of the present invention, the curvature of the roll barrel changes over the entire length.

The roll crown is formed so that the entire roll barrel has a convex shape, and is formed in a left-right asymmetrical shape so that its maximum diameter portion is shifted in the axial direction with respect to the longitudinal center of the roll. Moreover, since the rolls are configured to be movable in the axial direction, the initial crown of the rolls relative to the rolled material can be changed by changing the direction and amount of movement of the rolls in the axial direction. A rolling mill with excellent controllability in which the plate crown of a rolled material can be freely adjusted using rolls can be obtained.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS A rolling mill that is an embodiment of the present invention shown in the drawings will be described below.

FIG. 1 and FIG. 2 are diagrams for explaining the present invention in detail.

4- As shown in FIG. 1, when rolls 1 and 2 are placed in the center of the rolling mill, the roll initial crown for a certain sheet width is Co. Note that 4 is a rolled material. If the crown curve differs from a constant curvature curve such as a circular arc, and the curvature changes over the entire length of the roll as shown in Figure 1, then the roll can be centered around the mill as shown in Figure 2. On the other hand, if it is moved by a to make it point symmetrical, the crown relative to the plate width will change as shown in C.

Here, when the curves of the crowns of the rolls 1 and 2 are hyperbolic, the relationship between the roll axial movement amount a and the crown equivalent amount C is as shown in FIG.

However, if the curvature of the roll crown is constant over the entire length of the roll, such as an arc, the crown equivalent amount C will not change even if the rolls are moved relative to each other in the roll axis direction, and for a pair of rolls, the roll initial crown will be Only one type available.

On the other hand, a system has been devised in which the work roll is moved in the axial direction in order to make the wear of the roll uniform, but this method alone cannot achieve the effect of changing the crown as the object of the present invention. As explained earlier, the curvature of the roll crown is not constant throughout the length of the barrel, i.e. the curvature of the roll crown changes over the entire length of the roll barrel. The roll crown can be changed by relatively moving the roll crown in the roll axis direction.

The present invention focuses on the above-mentioned principle, and as shown in FIG. 4, the curvature of the roll crown formed by twisting over the entire length of the roll barrel is not constant. , 2a are arranged point-symmetrically with respect to the center 3 of the rolled material, and the roll crowns la and 2a are formed so that the entire roll barrel has a convex shape. Further, the roll 1 is formed in a left-right asymmetrical shape with its maximum diameter portion being shifted in the axial direction with respect to the center of the rolling mill and the longitudinal center of the roll, respectively.
2 is configured to be relatively movable in the axial direction.

In other words, in the rolling mill of this embodiment, the roll crowns la and 2a, which are formed in a convex shape over the entire length of the roll barrel, are different from the roll crown curves of each roll 1 and 2, as shown in FIG. The symmetry axes 1c and 2c are axially shifted from the longitudinal center of the rolls, and each of these rolls 1 and 2 is
The roll crown la, 2a formed in the center of the rolling mill 3
They are arranged in a point-symmetrical relationship with respect to. In this case, in the roll movement direction, if the upper roll 1 is moved axially to the right and the lower roll 2 is moved to the left in the axial direction, the roll crown with respect to the rolled material 4 will become smaller, and if it is moved in the opposite direction, the roll crown will become larger. The ability to vary the roll crown in either direction provides control advantages.

〔Effect of the invention〕

As described above, according to the present invention, instead of having to have rolls with various types of crowns in the past, it is only necessary to have rolls with one type of crown, and the rolls can be moved in different directions. This is a rolling mill with excellent controllability that enables roll crown control, which brings great benefits in terms of economy.

[Brief explanation of drawings]

Fig. 1 is a diagram for explaining the present invention in detail, Fig. 2 is a diagram for explaining how the crown equivalent amount changes when the roll is moved in the axial direction, and Fig. 3 is a diagram showing the roll movement amount and the crown equivalent amount. FIG. 4 is an embodiment of the present invention, which shows the relationship between
FIG. 2 is a diagram showing a rolling mill equipped with rolls having asymmetrical crowns. 1...Top roll, 2...Bottom roll, la, 2a...
roll crown.

Claims (1)

[Claims] 1. A rolling mill in which a pair of rolls forming a roll crown whose curvature changes over the entire length of the roll barrel is arranged point-symmetrically with respect to the center of the rolling mill, The roll crown is formed so that the entire roll barrel has a convex shape, and is formed in a left-right asymmetrical shape so that its maximum diameter portion is shifted in the axial direction with respect to the longitudinal center of the roll. A rolling mill characterized in that the rolls are configured to be movable in the axial direction.