JPS6146306A - Rolling roll - Google Patents

Abstract

PURPOSE:To improve the resistance to stress of a roll by forming annular recessed parts at both-side end surfaces of a roll body and forming each part, from the recessed part to a roll neck, into a curved surface. CONSTITUTION:Annular recessed parts 4 are formed at both-side end surfaces of a body 1, and each part 4 from the recessed part 4 to a large-diameter axial part 2a is formed into a curved surface. The radius of curvature of said curved surface can be increased with the increase in the depth L of recessed part 4 and a concentration of stress to the part 4 is relaxed, but not preferable when it is to much increased, because of its effect on the deflection or roll.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a rolling roll, and particularly to a rolling roll with excellent stress resistance.

(Prior art and its problems) In general, a rolling roll supported by an oil film bearing such as a moboil bearing or a metas bearing has a roll neck portion (2) of the bearing as shown in FIG. 5(a), for example. It is tapered to make it easy to put on and take off. In addition, in the figure (
It is a 11ri roll body.

On the other hand, the pressure supported by oil film bearings such as cylindrical roller bearings and tapered roller bearings (roll neck! It is processed into a shape.

In the case of the rolling roll having the shape shown in FIG.
+ indicates that the roll neck part (21 is an oil film bearing that supports a tapered rolling roll) is processed to have a curved surface in order to prevent large bending stress, that is, stress concentration, during rolling. This has the advantage that the wall thickness of the bearing is thin, so the diameter of the round neck part (2) can be made large, and the a-lunchic can be made more compact. The drawback is that it requires low speed rolling (approximately 4,000 rpm or more) and cannot be operated at low speeds (+2 to 20 rpm).

Furthermore, oil film bearings cause plate thickness fluctuations due to key grooves and roll gap changes due to oil film fluctuations during roll rotation acceleration/deceleration, and are also a cause of disturbances in automatic plate thickness control rolling (man Ca).

For this reason, there has recently been a trend to use bearings for backup rolls in thick plate rolling mills, which can withstand high load ranges, withstand low speed rolling, and have little roll gap change.

At this time, when changing from an oil film bearing to a roller bearing,
Manufacturing new roll chocks, bearings, and rolling rolls would increase equipment costs, so the existing roll chocks were changed from oil film bearings to roller bearings, in other words, the roll necks currently used were tapered. It is advantageous to rework the shaped rolled n-ru into a straight roll neck and make it hexagonal in terms of cost.

In this case, it is better to use the installation space for the chock of a conventional oil film bearing without machining the inner diameter of the roll chock of the existing oil film bearing, or with only minor machining, to maintain the wall thickness of the chock before modification. This does not reduce the rigidity of the chock, and it can be used by simply reprocessing the crowbar neck from the tapered shape shown in No. 5 (a) to the straight shape shown in the same figure (b), without the need for major modification. , the cost I■ is 4 advantageous.

However, if the rollers are modified to be used as roller bearings without machining the inner diameter of the roll chock, the radius of curvature of the curved surface machined part at the boundary between the roll neck part and roll body (υ + 31) will be as shown in Figure 2'fE6. As shown, the half radius of curvature iR1 after processing is inevitably smaller than the radius of curvature R1 before processing.

As a countermeasure for this, for example, as shown by the two-dot chain line in FIG. By making the solid line thinner than the solid line shown in , it is possible to process a curved surface with a radius of curvature equal to or greater than that before processing.

However, increasing the length of the curved surface processing section means that the bearing section must be shortened and the roll chock must be reprocessed. Furthermore, reducing the diameter of the U-runch reduces the strength of the roll neck portion (21) and requires reworking the roll chock.

If the rollers are used for a bearing as described above without doing this, the radius of curvature will inevitably become smaller.

The above has described the reprocessing of rolling rolls when modifying the roll neck section from oil film bearings to roller bearings. The rolling is the fifth
The straight shape shown in Figure (b) is used, and the curved surface processing portion of the boundary 1 (3) is naturally designed and processed so as to be kept within the allowable stress of the roll.

However, in recent thick plate rolling, rolling is often performed at a stress that exceeds the allowable stress.

For example, cryogenic rolling for processing heat treatment, heavy reduction rolling for crimping internal defects, etc. In some cases, the rolling process exceeds the allowable load, and in such cases, a stress greater than the allowable stress naturally acts on the curved surface processed portion of the boundary section (3), and this type of situation is repeated. When the roll is returned, the curved surface processed portion is subjected to extreme stress, and cracks are generated in the portion, resulting in breakage of the roll.

One way to prevent this phenomenon is to increase the radius of curvature of the curved surface processing portion, thereby making it possible to withstand large concentrated stress.

However, it is difficult to increase the radius of curvature of the curved part of the roll neck part currently in use with a straight shape, and in some cases rolls with a large radius of curvature are manufactured. This posed the problem of requiring either a new roll chock to be manufactured or an existing roll chock to be modified, resulting in an increase in equipment costs.

(Means for Solving the Problems) The present invention has been made in view of the above-mentioned actual situation of IC], and is modified from an oil film bearing to a roller t-bearing without reworking the inner diameter of the current roll chock. When doing so, it is necessary to use a rolling roll that is suitable for reprocessing from a roll with a tapered roll neck to a straight rolling roll without reducing the strength of the current roll, or to replace the existing roller bearings with that ft. The purpose of the present invention is to provide a rolling roll suitable for use and reprocessing into a rolling roll with excellent stress resistance, and is constructed as shown below.

That is, in the rolling roll according to the present invention, in the rolling roll constituted by a roll body and a roll neck, a ring-shaped recess is formed on both end surfaces of the roll body, and a curved surface is formed from the recess to the roll neck. The gist is what was formed.

(Example) Hereinafter, a rolling roll according to the present invention will be described based on an example shown in FIGS. 1 to 3.

In the drawing, (II is a roll adjustment part that is in direct contact with the work roll, (2) is a roll neck part located at both ends of the roll body 1υ and supported by rolling bearings (not shown)), Neck part (2) is roll body U+
It is formed from a side large diameter shaft part (2&), a medium diameter shaft part (2b), and a small assembled shaft part (20), and the outer circumferential surface of each of these shaft parts is formed in a straight shape.

In the roll roll according to the present invention, the boundary part (3) between the roll body 111 and the large diameter shaft part (2&) of the roll neck part (2) of the roll roll having the shape described above has the following shape. It is something that can be achieved.

In other words, ring-shaped recesses (
4) A curved surface is formed from the recessed portion i41 to each large diameter shaft portion (2&).

The larger the depth 9) of the recess (4), the larger the radius of curvature of the curved surface, which can alleviate the stress concentration on this part, but if it is too large, the roll barrel will be damaged. This is undesirable because it affects the deflection of the material. That is, the depth aJJ is preferably within 100 cm.

In this way, by providing the recesses 141 on both end faces of the roll body (υ) and forming the recesses g141 and the large diameter shaft part (2&) into curved surfaces, the roll body (11 and the roll neck part (
The boundary +31 in 2) can be made into a curved surface with a larger radius of curvature.

For example, as shown in Fig. &12, a roll tray with a tapered roll neck (2) (11N) can be used without machining the inner diameter of the roll chock (as described above). ) 1/2) shape (solid line) for rolling bearings, conventionally the curved surface machined part has a shape as shown by the broken line in Figure 2, and the shape before machining (solid line) The radius of curvature is smaller than that of the dashed line), but by providing a recess (a) on the end face of the roll adjustment part (1J), it becomes possible to form the shape as shown by the solid line in the figure, and the shape before machining ( The radius of curvature can be equal to or greater than that (dotted chain line in the figure).

On the other hand, as shown in Fig. 3, if the stress resistance is to be improved without reworking the diameter of the roll neck part (2) of the current rolling bearing roll, that is, the inner diameter of the roll chock, a recess (41) is provided. By forming it into a curved surface, it is possible to obtain a radius of curvature larger than the shape before machining (dotted chain line in FIG. 3) (solid line in the same figure).

(Body A side) Figure 4 shows maximum load: 5000), mill motor: 3
700 cases x 2 units, roll rotation speed: 5 to 80 rpms Work roll taze: diameter φ1000■, roll body length 430
A 0+++ thick plate rolling mill is equipped with a roll neck part (2 is a teno-shaped rolling roll) as shown in FIG. A roll reworked into a L/-) shape and a roll according to the present invention are used as pull-up rolls, and the stress acting on the curved portion of each roll is calculated as the rolling load. This is the result of an investigation in relation to

The person in the figure has a diameter of roll body 11+: 1800cm, a body length:
Maximum diameter of roll neck at 4300+m: 116
0m, minimum diameter: 10100 (1, radius of curvature of boundary part 131 formed in a curved shape: 80m roll neck part (2)
B is a tapered rolling roll (the shape shown in Fig. 45), and B is a roll neck part of the rolling roll of A mentioned above with a large diameter shaft part (-bending: φ1080 mm, a medium diameter shaft part (2b)). Diameter: φ
1000 mm, reworked rolling roll with curvature radius of 170 m1c at boundary part 131 (shape shown in Figure 5 (mouth))
, a is the roll roll according to the present invention, and when reprocessing the rolled roll part (2)'g of the roll roll of the person mentioned above in the same manner as B: 3Q
A ring-shaped recess 14 with a diameter of 14 mm is formed, and an Il with a curvature of
! It is formed in one plane.

As is clear from FIG. 4, the pressure 1geI-rule (0 in FIG. 4) according to the present invention can have a larger radius of curvature than that of the conventional rolling roll (A and B in FIG. 44). Therefore, compared to conventional rolling rolls, the stress acting on the curved surface portion at the boundary +3) is significantly reduced under the same rolling load.Furthermore, with conventional rolling roll B, the maximum rolling technique at the maximum allowable stress is achieved! are 4,500) and 5,500 respectively.
), but with the rolling roll (0) according to the present invention, rj
Up to 6000) is possible.

(Effects of the Invention) As described above, the rolling roll according to the present invention has excellent pressure resistance, and for example, the rollers can be modified into roll necks for bearings without reworking the roll chock. In this case, it is possible to rework the existing rolls without damaging their strength and stress resistance, and it is also possible to improve the stress resistance of the existing rolls without having to rework the existing roll chocks for ζ rolling bearings. .

In the above explanation, the case where an existing rolling roll is reprocessed has been described, but the rolling roll of the present invention can also be used when manufacturing a new rolling roll.
: J can be made into a material with a high stress resistance and an immediate n ratio.

[Brief explanation of drawings]

°Figure 1 is a drawing showing an embodiment of the rolling roll according to the present invention, where () is a partially cutaway front view, (b)) is a side opening, and
The figure is an explanatory diagram of a case in which a rolling roll with a tapered roll neck part is modified into a press gel roll according to the present invention, and Figure 3 is an explanatory diagram of a rolling roll with a straight roll neck part.
Figure 4 is a diagram showing the relationship between stress and rolling load between the rolling roll according to the present invention and a conventional rolling roll; Figure 5 is a front view showing an example of a conventional rolling roll; The roll neck part is tapered, (B) is also a straight one, and Figure 6 (A) is an explanatory diagram when converting a roll roll with a tapered roll neck part to a straight roll. (b) An enlarged view of the beam. 111 rj, roll body, (2) roll neck,
(3) is the boundary, and 141 is the recess. ' Patent applicant Sumitomo Metal Industries, Ltd. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] (1) A rolling roll consisting of a roll body and a roll neck, characterized in that a ring-shaped recess is formed on both end faces of the roll body, and a curved surface is formed from the recess to the roll neck. rolling roll.