JPS61235013A - Rolling mill grinding device - Google Patents

Abstract

PURPOSE:To prevent vibration of a grinding device by installing a plurality of whet stones combined in a concentric cylindrical form and by pressing side end faces of these whet stones to an outer peripheral surface of rolling mill. CONSTITUTION:A whet stone 30 is composed as a two layer form by fitting a cylindrical internal whet stone 10 and an external whet stone 20 in a concentric cylindrical form. A bearing 12 is interposed between the whet stone 10 and a shaft 16 of the external whet stone 20, and a bearing 13 is arranged between shaft 11 and 16. The internal whet stone 10 and the shaft 11 are supported freely rotatably to the external whet stone 20 and the shaft 16. By means of this mechanism, the internal whet stone 10 and the external whet stone 20 are capable to rotate in a different number of rotations, without being in contact with each other and independently. When the roll grinding is performed by rotating the whet stone 30 subserviently by the rotation of the roller, if the external whet stone 20 is worn off, the internal whet stone 10 also rotates in a different number of rotations without causing a chattering vibration. And as a result, vibration of the grinding device is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a mill roll grinding apparatus that is capable of grinding a work roll of a hot rolling mill or the like while it is installed in the rolling mill.

<Prior art> In a rolling line such as a hot rolling mill, the wear of the work roll during rolling is much greater than that of the backup roll, especially when the surface of the work roll is passed through in contact with the strip. The surface of the strip is severely roughened, and furthermore, large amounts of local wear occur in the portion where the edge of the strip passes. As a countermeasure for this,
In addition to performing scheduled rolling in which the width order of the rolled sheets was regulated, the rolls were replaced periodically, and the used roll surface was ground with a grinding device installed outside the line for reuse. In this schedule rolling, rolling is performed by determining the order of the width of the rolled strips so that the width of the rolled strips is first rolled and then the narrower width strips are rolled. If this is done, rolling can proceed without being affected by wear on the roll surface, especially local wear at the edge of the plate.

However, in such scheduled rolling, the rolls must be rearranged frequently, and it takes a lot of time to attach and detach the rolls from the rolling mill, which increases the time the workpiece is down, which seriously impedes production efficiency. . In addition, it requires a lot of labor and the raw material slabs must be prepared in accordance with the order of the widths of the rolled plates, so there are problems such as the need for a large slab storage area.

For this reason, we have developed an online roll grinding device that grinds the rolls during rolling while they remain installed in the rolling mill, extending the roll change cycle, while also enabling schedule-free rolling that is not restricted by the strip width order. Development is underway.

This online roll grinding device is built into a rolling mill by attaching a grinding device to it and grinds nine rolls. Figure 2 shows an example of its grinding method, and Figure 3 shows its side profile. As shown, the grindstone 3 is pressed against the surface of the rotating work roll 1 for grinding. Various online roll grinding methods have been proposed up to now, but in this example, the side end surface of the cylindrical grinding wheel 3 is pressed against the surface of the work roll l in an inclined state.
Sliding friction is generated when the grindstone 3 is driven to rotate as the work roll rotates ten times, thereby grinding the work roll 1. In this method, there is no need to forcibly drive the grindstone 3 to rotate, so a drive device for the grindstone 3 is not required, which is very advantageous in terms of equipment. The grindstone 3 is supported by a support shaft 4 that rotates together with the grindstone 3, and the rotation axes of the grindstone 3 and the support shaft 4 are provided at an angle that is not perpendicular to the axis of the work roll 1. Therefore, the side end surface of the grinding wheel 3 is at an angle θ with respect to the surface of the work roll 1.
and are diagonally touching.

<Problems to be solved by the invention> Grinding using a cylindrical grindstone and rotating the grindstone along with the rotational force of a rolling roll is mechanically simple and has excellent grinding performance. . However, in this method, if the grinding surface of the grindstone is worn and the contact width becomes too large, a problem arises in that the entire grinding device vibrates. When this vibration occurs, the surface of the grindstone becomes uneven and does not disappear (31), and the vibration becomes unstoppable, eventually making grinding impossible.

In other words, as the grinding progresses, the grinding surface of the whetstone wears out, and the entire surface of the grinding surface comes into contact with the outer circumferential surface of the rolling roll.As shown in FIG.
The contact width of the grinding wheel 3 fixed to the grinding wheel 3 exceeds the allowable value, and a sudden vibration occurs. The reason for this is thought to be that since the grinding surface, which is the side end surface of the grindstone 3, is annular in shape with a width, there is a difference in circumferential speed between the outer circumferential side and the inner circumferential side.

SUMMARY OF THE INVENTION An object of the present invention is to provide a grinding device that eliminates the drawbacks of conventional roll grinding devices and can perform good grinding work without generating vibrations.

Means for Solving the Problems> The rolling roll grinding device of the present invention includes a cylindrical grindstone that is integrally provided with a rotatable rotating shaft, and a grindstone that rotates concentrically relative to the grindstone through bearings. The grinding wheel is characterized in that it comprises at least one freely supported cylindrical grindstone, and the side end surfaces of these grindstones are pressed in an inclined state against the outer circumferential surface of a drivingly rotating rolling roll.

<Operation> A plurality of grindstones combined in a concentric cylindrical shape rotate at respective circumferential speeds, the grindstone inside the claw 9 rotates at the inside speed, and the outside grindstone rotates at the outside speed. Therefore, as a result of each of the plurality of grindstones rotating at its own speed, chatter 9 caused by the speed difference is eliminated.

<Example> As shown in FIG. 1 showing the cross-sectional structure of an example of the rolling roll grinding device of the present invention and FIG. 2 showing the right side shape thereof, in this example, a cylindrical and relatively thin walled A two-layered whetstone 3 is formed by fitting the inner whetstone 10 and the outer whetstone 20 in a concentric cylindrical shape.
A shaft 11 passes through the center of the inner grindstone 10. Axis 1 of the inner whetstone 10 and the outer whetstone 20 described below
A bearing 12 is interposed between the tip flange portion of the shaft 11 and a bearing 13 between the stepped portion of the shaft 11 and the stepped portion of the shaft 16. 1
1 is rotatably supported concentrically with an outer grindstone 20 and its shaft 16, and a stopper 15 is screwed into the end of the shaft 11 with a bearing 14 interposed between it and the step of the shaft 16. ing. A shaft 16 passes through the center of the outer grindstone 20, and a stopper 17 is fitted on the outer periphery of the shaft 16.
An outer grindstone 20 is placed between the tip flange of 6 and the stopper 17.
The outer grindstone 20 is fixed to the shaft 16 by sandwiching the bottom of the shaft 16, and the pivot 16 is rotatably supported by a bearing or the like (not shown).

Therefore, the inner grindstone 10 and the outer grindstone 20 are capable of rotating independently at different rotational speeds without contacting each other. The grinding wheel 30 configured in this way is pressed against the outer circumferential surface of a work roll (not shown) with its axis of rotation obliquely, and the grinding wheel 30 is rotated by the rotational force of the work roll to eliminate the shear generated between them. Grinds the work meal using bevel friction. In this case, first, the outer grindstone 20 rotates in contact with the work roll surface, and as the grinding progresses and the grinding surface of the outer grindstone 20 becomes worn, the grinding surface of the inner grindstone 10 also comes into contact with the surface of the work roll. It comes into contact with and rotates.

Since the inner whetstone lO and the outer whetstone 20 can rotate independently from each other at different rotational speeds, each rotates at a different driven circumferential speed v1 + vt due to contact with the roll surface, and There is no large difference in circumferential speed between the outside and inside, and therefore grinding can be continued without vibrations caused by chatter.

In this embodiment, a configuration in which cylindrical grindstones are combined in two layers has been described, but the present invention is not limited to this embodiment, and can be modified according to the required diameter of the grindstone or the width of the grinding surface. , three layers, four layers, or any other multilayer structure.

<Effects of the Invention> The rolling roll grinding device of the present invention uses a cylindrical grindstone and has a simple structure that does not require a rotational drive source for the grindstone, and is highly efficient without causing chatter vibration due to wear of the grindstone. It is possible to perform high quality rolling roll surface grinding.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of one embodiment of the rolling roll grinding device of the present invention, Fig. 2 is a right side view thereof, Fig. 3 is a work conceptual diagram showing the grinding method of a conventional rolling roll grinding device, and Fig. 4 5 is a side view thereof, and FIG. 5 is an enlarged view showing the state of contact between a grindstone and a roll in a conventional grinding device. In the drawing, 1 is a work roll, 3.30 is a grindstone, 10 is an inner grindstone, 11 is a shaft, 12, 13.14 is a bearing, 1
5 is a stopper, 16 is a shaft, 17 is a stopper, and 20 is an outer grindstone. Patent applicant: Mitsubishi Heavy Industries, Ltd. (1 other person)
Sub-Agent Patent Attorney Hikaru Ishibe (and 1 other person) Figure 1, Figure 211

Claims (1)

[Claims] A cylindrical whetstone provided integrally with a rotatable rotating shaft, and at least one cylindrical whetstone supported concentrically and relatively rotatably with respect to the whetstone through bearings, and these whetstones A rolling roll grinding device characterized in that a side end surface of the rolling roll is pressed in an inclined state against the outer circumferential surface of a driving and rotating rolling roll.