JPH11147117A - Working roll and ceramics roll and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To clearly print geometric pattern or decorative pattern on a rolled material and to form the geometric or the decorative pattern with the difference in level of the rolled material by providing at least one part of a recessed groove part and protruded projection part on the surface of barrel part of a working roll and making the coefficient of thermal expansion on the surface of the barrel part in the specific range. SOLUTION: After applying mirror-finishing to the surface of the barrel part of the ceramics roll 1 of which the coefficient of thermal expansion of the surface of the barrel part of the working roll is 1.0-10.0×10<-6> , a negative type sensivity dry film 20 is wound on the whole surface of the barrel part. An original film 21 is arranged so as to be closely brought into to contact on the dry film 20. For the original film 21, the desirable geometric or decorative pattern, etc., is formed before closely contacting. The exposure is applied to the whole barrel part of the ceramics roll 1 and thereafter, the original film 21 is taken out and the developing is executed by atomizing sodium carbonate solution onto the whole barrel part of the ceramics roll 1. Successively, shot blasting is executed and the dry film 20 is removed with methyl ethyl keton.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work roll used for rolling a sheet material, and more particularly to a ceramic roll, a method for producing the same, and a rolling mill using the ceramic roll.

[0002]

2. Description of the Related Art There are various techniques for processing the surface of a body of a ceramic work roll for rolling a sheet material as follows.

Japanese Patent Application Laid-Open No. 64-45755 discloses a ceramic roll body for matting a rolled product and improving the adhesion of a rolled product to the ground of a rolled product in a plated product or a decorative product. A surface dulling process, that is, a method for imparting a roughness of 2 μm or more is described, and a rolling mill using the processed ceramic dull roll is described.

[0004] A ceramic roll for a wire is known in which a semicircular dent is formed in the ceramic roll, and the wire or bar is extended at the dent.

[0005] Further, as a technique for forming a geometric pattern or a decorative pattern such as characters, symbols, pictures, etc. on the surface of a rolled material,
2. Description of the Related Art In general, a technique for forming a pattern on a roll surface to transfer a desired geometric pattern or decorative pattern to a rolled product is known.

Japanese Patent Application Laid-Open No. 8-24913 discloses a difference in surface roughness (a mirror surface portion of 0.07 μm or less in Ra and a surface roughness of Ra of 0.07 μm or less).
A ceramic roll in which a pattern of a transfer pattern is formed by a rough surface portion (1 μm to 1 μm) is described. Further, in this technique, a shot blast method or an etching method is used to increase the roughness of the ceramic roll.

Further, as a technique of engraving a pattern on the surface of a metal work roll to obtain a rolled material with a pattern, Japanese Patent Application Laid-Open No.
-47016.

[0008]

In the technique disclosed in Japanese Patent Application Laid-Open No. 8-24913, a transfer pattern is formed due to a difference in roughness of the body surface of the ceramic roll.
The pattern transferred to the rolled product was thin and the outline of the pattern was blurred. In other words, if only the difference in surface roughness (mirror surface portion, rough surface portion) is transferred, the difference will not be clear when transferred, and the accuracy of the pattern transferred to the rolled material will be inferior. In addition, as the rolling of the rolled material was repeated, the difference in the difference in surface roughness disappeared, and it was difficult to maintain the transfer of the pattern for a long period of time.

Further, since the surface roughness is lowered while the surface roughness is reduced, the roughness of the rough surface portion is limited, and it is difficult to increase the difference between the mirror surface portion and the rough surface portion.

As a method of forming a semicircular dent portion on a ceramic roll, there is a method of preparing a ceramic roll material having a dent portion and sintering the material. However, this method can form a semicircular dent which is a large gentle curved surface, but it is difficult to reduce the width and depth of the dent and it is difficult to perform the sintering before sintering. Due to the formation, the dimensional accuracy was inferior. Further, it is difficult to process and form a dent on a ceramics roll after sintering due to the material properties of the ceramics. In other words, the ceramic material is very hard and brittle, so if a grinding blade or the like is used, the ceramic itself will crack,
When a polishing device or the like is used, it takes a very long time to form the dent portion, and the efficiency is low.

Further, when a pattern is engraved on the surface of a general metal work roll as described in JP-A-59-47016, a seizure phenomenon is liable to occur because the surface is not smooth but has many irregularities. , Stable rolling is difficult. In rolling, the temperature of the work roll is raised to a high temperature of 50 to 200 ° C. due to heat transfer from the rolled material and friction with the rolled material. In order to suppress this temperature rise, cooling water or the like is usually sprayed on the work roll surface to suppress the surface temperature rise. That is, the temperature of the work rolls rises and changes during rolling. Even if an accurate pattern is formed on the surface of a metal work roll due to such a rise in surface temperature and a change in temperature, the pattern itself changes due to thermal expansion, and it has been difficult to transfer an accurate pattern. Further, since the metal surface is engraved, the corners, which become the boundaries of the pattern, are rounded due to wear due to rolling, and it has been difficult to maintain clear transfer for a long time.

A first object of the present invention is to provide a work roll or a ceramic roll capable of transferring a geometric pattern, a decorative pattern or the like onto a surface of a rolled plate material with high accuracy.

A second object of the present invention is to provide a method of manufacturing a ceramic roll which can form a concave groove or a projection on the surface of the ceramic roll with high accuracy.

A third object of the present invention is to provide a rolling mill for transferring a geometric pattern, a decorative pattern, or the like onto a surface of a rolled plate with high accuracy.

[0015]

SUMMARY OF THE INVENTION A first object of the present invention is to provide:
In the work roll for rolling, the body surface of the work roll has at least one of a concave groove portion and a convex protrusion, and the body surface has a thermal expansion coefficient of 1.0 to 10.0 × 1.
It is accomplished by a 0 ^-6.

Further, a first object of the present invention is to provide a work roll for rolling, wherein at least one of a concave groove portion and a convex protrusion portion is provided on a body surface of the work roll to form a rolled surface, This is achieved by making the rolling surface a ceramic.

Alternatively, a first object of the present invention is to provide a ceramic roll for rolling, wherein at least one of a concave groove portion and a convex protrusion portion is formed on a body surface of the ceramic roll. Is achieved by

A second object of the present invention is to provide a method of manufacturing a ceramic roll for rolling, wherein after sintering, at least one of a concave groove and a convex protrusion is formed on the body surface of the ceramic roll by a shot blast method. This is achieved by forming one.

A third object of the present invention is to provide a rolling mill having upper and lower work rolls for rolling and a support roll for supporting the upper and lower work rolls, wherein at least one of the upper and lower work rolls is made of ceramic. And at least one of a concave groove portion and a convex protrusion portion is formed on the body surface.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In general, during rolling, the temperature of the surface of a work roll gradually increases due to heat transfer from a rolled material, processing heat due to rolling, and the like. Then, in order to suppress the temperature of the work roll during rolling from becoming high, cooling is performed by spraying cooling water or the like onto the work roll surface. That is, the work roll repeatedly changes the temperature during rolling, and the temperature change is performed in a range of approximately 50 to 200 ° C. That is, in the work roll, thermal expansion is repeated in an arbitrary range during rolling.

In a conventional metal work roll made of a high-speed material for printing a pattern pattern, even if an accurate pattern pattern for transfer is formed on the roll surface, the dimensional accuracy at room temperature at the time of forming the pattern pattern is not sufficient. Therefore, in the temperature range during rolling, the accuracy is lost due to thermal expansion. Further, the degree of thermal expansion due to a temperature change during rolling is large, and it is difficult to perform rolling while maintaining stable dimensional accuracy.

In the present invention, attention was paid to a temperature rise during rolling of a work roll for printing a pattern pattern and a temperature change during rolling.

FIG. 5 shows the metal material, ceramics and coefficient of thermal expansion of a conventional work roll for pattern pattern printing.
FIG. 5 shows a high-speed material as a conventional metal material and Sialon as a ceramic.

The high-speed steel has a coefficient of thermal expansion of about 12 × 10 ⁻⁶ . Normal temperature 20 ° C, high-speed steel material temperature 50 ° C, 10
In the case of temperatures of 0 ° C., 150 ° C., and 200 ° C., the temperature differences from room temperature are 30 ° C., 80 ° C., 130 ° C., and 180 ° C., respectively.
Therefore, as shown in FIG.
3.6 × 10 ^-4 when the high-speed material temperature is 50 ° C., 9.6 × 10 ^-4 when the high-speed material temperature is 100 ° C., 15.6 × 10 ^-4 when the high-speed material temperature is 150 ° C., and 200 ° C. when the high-speed material temperature. Time 21.6
× 10 ^-4 .

If a metal working roll having a body length of 800 mm is manufactured from this high-speed steel material and used for rolling, the body length is 800 mm at room temperature and 80.2 at 50 ° C.
88 mm, 800.768 mm at 100 ° C, 80 at 150 ° C
1.248 mm, 801.728 mm at 200 ° C. In other words, when the body length is 800 mm, the length expands by 0.288 mm or more at room temperature and during rolling, and changes greatly. Also, between 50 and 200 ° C. during rolling, the length is
It fluctuates greatly between 0.288 mm and 1.728 mm.

Further, similarly to the body length, the body diameter of the work roll also changes due to a temperature rise or a temperature change. Since such a dimensional variation occurs, even if a pattern is accurately formed on the work roll body, if the rolling for printing is actually performed, the pattern pattern to be printed will be out of dimension. That is, the pattern pattern changes due to thermal expansion due to a rise in rolling temperature, and the pattern pattern changes variously due to thermal expansion fluctuation due to temperature change during rolling.

On the other hand, a sialon material, which is a kind of ceramics, has a thermal expansion coefficient that is about １ ／ that of a metal or the like.
About 3.2 × 10 ⁻⁶ . And, as shown in FIG.
0.96 × 10 ^-4 at ℃, 2.56 × 10 ^-4 at sialon temperature 100 ° C., 4.16 × 10 ^-4 at sialon temperature 150 ° C., 5.5 at sialon temperature 200 ° C.
76 × 10 ^-4 .

As in the case of the above-mentioned high speed steel, if a ceramic work roll having a body length of 800 mm is manufactured from this sialon material and used for rolling, the body length becomes
800mm at room temperature, 800.768mm at 50 ° C, 100
800.2048 mm at 80 ° C, 800.328 mm at 150 ° C,
It is 80.4608 mm at 200 ° C. That is, body length 8
In the case of 00 mm, the length expands only 0.4608 mm at most between the room temperature and the temperature during rolling, indicating a small change. Further, between 50 and 200 ° C. during rolling, the length fluctuated only within a small range of 0.0768 mm to 0.4608 mm, which was a small change.

Similarly to the body length, the body diameter of the work roll does not change much even when the temperature rises or changes. Since the dimensional variation is very small as described above, when a pattern is accurately formed on the body of the work roll and the rolling for printing is actually performed, the pattern to be printed becomes accurate.

That is, the change in the pattern pattern due to the thermal expansion due to the rise in the rolling temperature is small, and the various changes in the pattern due to the thermal expansion fluctuation due to the temperature change during the rolling are small.
Therefore, transfer (printing) with good dimensional accuracy is possible.

Here, the coefficient of thermal expansion is 1.0 to 10.0 ×
10 ^-6 is desirable. By setting it in this range, the dimensional accuracy of printing of a pattern or the like is good. The coefficient of thermal expansion of the ceramic is approximately 2.0 to 8.0 × 10 ^-6 ,
It can be seen that it is suitable for a work roll for pattern pattern printing.

As described above, since ceramics do not thermally expand much, even if various patterns are formed into concave grooves or convex protrusions, the groove width and the protrusion width are hardly affected by the temperature. Therefore, in the ceramics roll of the present invention, the pattern pattern is less affected by the temperature rise during rolling and the temperature change during rolling, so that a highly accurate pattern can be maintained and the pattern can be stably transferred to the rolled material. Recognize.

(Example 1) A ceramics roll of the present invention and a method for producing the same will be described below with reference to FIGS.

FIG. 1 is a sectional view of a ceramic roll according to one embodiment of the present invention, and FIG. 2 is a development view of a body portion of the ceramic roll according to one embodiment of the present invention.
FIG. 4 is a manufacturing process diagram of a ceramic roll according to one embodiment of the present invention, and FIG. 4 is an enlarged cross-sectional view of a groove portion on a body surface of the ceramic roll according to one embodiment of the present invention.

First, a method for producing a ceramics roll will be described. The ceramic used in this example is Sialon ceramics. The chemical formula of this sialon ceramic is represented by Si ₆ -2AlzOzNg-z,
Is 0 to 4.2 and is called β-sialon.

As shown in FIG. 4, the production process of the ceramics roll in this embodiment includes a granulation process 11, a powder compacting process 1
2, sintering process 13, shaft portion forming process 14, trunk portion polishing process 1
5 and a groove processing step 16 are sequentially performed.

In the granulation step 11, a β-sialon powder with z = 0.5 was used, a small amount of a binder was added, methanol was added, and the mixture was wet-kneaded and granulated by a spray-drying method.

In the compacting step 12, after granulation, a cold isostatic method was applied to compact into a column having a diameter of 105 mm and a length of 900 mm.

In the sintering step 13, after the compacting,
After degreasing by maintaining at a temperature of 40 ° C. for 40 hours, sintering was performed at a high temperature of 1700 ° C. in a nitrogen atmosphere to obtain a sintered body of Sialon ceramics.

In the shank forming step 14, after sintering, the metal cap 2
Is provided. The metal cap 2 is provided to improve processing accuracy. First, as shown in FIG.
Small diameter portion 5 in the roll axis direction at both ends of ceramics roll 1
To form That is, small-diameter portions are formed at both ends of the ceramic roll 1. Then, the metal pipe 4 is wound around the small diameter portion in a coil spring shape. The metal cap 2 having an inner diameter slightly smaller than the winding diameter of the metal pipe 4 was heated to about 800 ° C., thermally expanded, and fitted and fixed from above the metal pipe 4. . The metal cap 2 had a concave shape in the roll axis direction and was made of SUS304. The metal cap 2 was provided with a processing center hole 3 used for polishing the body. Further, a through hole 7 was provided in the center hole 3 in the roll axis direction.
By providing this center hole 3, the polishing accuracy of the body surface of the ceramic roll can be improved, and by providing the through hole 7, air can be removed at the time of fitting, and shrink fitting can be improved. In addition, the inner surface of the center hole 3 of the metal cap 2 is subjected to build-up welding of stellite having hardness higher than that of the metal cap, and the life of the center hole when polishing the surface of the body of the ceramics roll. Can be extended.

In the body polishing step 15, the body surface of the ceramic roll 1 was polished by pressing both centers using the center hole 3. Here, first, after performing cylindrical grinding using a diamond grindstone to rough-process to a predetermined size, finish polishing with loose abrasive is performed, and the powder compacting step 1 is performed.
The body diameter φ7 is about 80% of the size in 2.
Rolls having a size of 0 mm, a body length of 600 mm, and a total length of 720 mm were manufactured. As a result, it was possible to obtain a ceramic roll having high processing accuracy. That is, a mirror finish with a surface roughness Ra of 0.05 μm or less could be realized with high dimensional accuracy with a roundness of 1 μm or less and a cylindricity of 5 μm or less.

In the groove processing step 16, a groove was formed on the mirror-finished ceramic roll body surface by shot blasting. Conventionally, shot blasting is used simply for changing the surface roughness in the processing of ceramic rolls and metal rolls. In particular, for dulling, it is widely used because a uniform rough surface can be obtained. Has been used.

In this embodiment, a hard and brittle ceramic roll is subjected to groove grinding using a shot blast method. Hereinafter, a specific method will be described.

In this embodiment, the character ROLL is used as an example of a geometric pattern or a decorative pattern. In this example, after the body surface of the ceramic roll 1 was mirror-finished, a negative photosensitive dry film 20 having a thickness of 100 μm was wound around the entire body of the ceramic roll 1. And the dry film 2
The original film 21 was provided in close contact with the original film 21. Here, a character pattern of ROLL, which is an example of a desired geometric pattern or decorative pattern, is formed on the original film 21 before the close contact. The character pattern ROLL includes a curved portion (circle portion), a straight line portion, an intersection portion, a corner portion, and the like, and the respective transfer effects can be confirmed. The size of one character of this character pattern was 3 mm × 3 mm. FIG. 4A shows an enlarged sectional view of this state.

The thickness of the character, that is, the thickness of the concave groove to be formed, was 0.38 to 0.4 mm.

In the state shown in FIG. 4A, the entire ceramic roll body was exposed. Thereafter, the original film 21 was removed, and a 1% sodium carbonate solution was sprayed on the entire body of the ceramic roll and developed to expose the character pattern portion. As a result, FIG.
As shown in the enlarged sectional view of (b), the dry film 20 does not exist in the character pattern portion, and the dry film 20 remains in portions other than the character pattern portion.
Was formed on the roll surface.

The original film 21 for forming such a character pattern can easily form various patterns, and various geometric patterns or decorative patterns can be formed on the original film 21. , Dry film 2
Various pattern patterns according to 0 can be easily formed on the roll surface.

Next, in the state of FIG. 4B, shot blast is performed. In order to uniformly process the entire surface, the process was performed while rotating the ceramics roll 1 about the roll axis. The shots used were SiC abrasive grains having an average particle size of 90 μm. In addition, the type of the shot is determined in consideration of the material of the ceramic roll 1 of this embodiment.
SIC (hardness: about Hv1600)
Hv2400). By using such a shot, a groove can be efficiently formed.

After the shot was jetted, the dry film was removed with methyl ethyl ketone on the surface of the body of the ceramics roll 1.
A concave groove 9 having a depth of 12 to 0.14 mm and a width of 0.38 to 0.4 mm
Could be provided. In this embodiment, the concave groove is described, but the same applies to the formation of the convex protrusion. Here, the depth of the concave groove 9 is set to about 0.1 mm. The depth is set according to a desired printing pattern, but is preferably 0.1 μm or more. If it is less than 0.1 μm, the steps of the concave grooves and the convex protrusions are not clear, and even if rolling for transfer (printing) is performed, the boundary of the pattern is not clear, and it is 0.1 μm or more. Is desirable. In addition, it is desirable that the level difference is not more than about one half of the roll radius in view of the strength of the roll. However, the roll strength, the roll diameter, and the like should be determined according to the desired amount of unevenness of the pattern.

FIG. 2 is a developed view of a body portion of a ceramics roll on which a character pattern is formed in the present embodiment. This is developed based on the lines A, B, C, and D shown in the cross section of the roll in FIG. In this manner, a sign obtained by inverting the sign of the desired ROLL to be printed on the rolled material is formed on the roll body.

The angle .theta. Between the side surface of the concave groove 9 and the surface of the body of the ceramic roll 1 is approximately 90 degrees, and the tip A of the corner is not rounded. It was a shape. In this embodiment, since the ceramics roll 1 is used, the wear resistance is excellent, the tip A of the corner is hard to be worn, and the sharpness can be maintained for a long time. Furthermore, since the concave groove 9 and the convex protrusion are formed by shots, the roughness of the formed portion does not become excessively rough.
Appropriate hardness can be secured. For example, it is possible to make the surface as rough as the mirror-finished surface of the body surface.

Here, the negative photosensitive dry film 2
The thickness of 0 is desirably about 100 μm. If it is too thin, the hard film hits and the dry film 20 is removed, and a desired pattern cannot be obtained. If the thickness is too large, the dry film 20
It is difficult for shots to enter the gaps between the pattern patterns to be formed, and the efficiency of groove formation is poor. Therefore, it is desirable to select the thickness of the dry film 20 in consideration of the shot size and the shot hardness so as to improve the processing efficiency.

In this embodiment, the concave groove 9 has been described, but the same applies to the formation of the convex protrusion.

In this embodiment, the integrated ceramic roll is described. However, a roll having a composite structure of metal and ceramic may be used. For example, a ceramics layer may be formed on the surface of a columnar metal material serving as the roll axis. Various methods such as a sleeve type and a thermal spraying method can be applied as a method for forming the ceramic layer.

Next, a case where the ceramic roll 1 manufactured according to the present embodiment is used in a rolling mill will be described. FIG. 6 shows a four-high rolling mill according to one embodiment of the present invention, and FIG. 7 shows a six-high rolling mill according to one embodiment of the present invention.

The four-high rolling mill shown in FIG.
7, an upper work roll 31 and a lower work roll 32 for rolling a plate, and an upper work roll 31 and a lower work roll 32
Upper reinforcing roll 35 which is a supporting roll for supporting
And a lower reinforcing roll 36 are provided. In the present embodiment, the ceramic roll 1 in which the character pattern is formed on the body surface is applied to the upper work roll 31. And
The lower work roll 32 was a ceramic roll having no character pattern formed on the body surface. The shafts of the upper work roll 31 and the lower work roll 32 are rotatably supported by bearings 41 and 42 for the upper work roll and lower work roll, respectively. , Each bearing 4 for upper reinforcing roll
5 and a lower reinforcing roll bearing 46 so as to be rotatable.

The rolling load is applied to the rolled sheet material 49 from the upper work roll 31 via the upper reinforcing roll 35 by a rolling device 48 attached to the housing 47. In the rotary drive mechanism of the present embodiment, the upper work roll 31 and the lower work roll 32 are made of ceramics having poor rigidity, and have a small diameter, so that the work rolls are not driven directly but indirectly. That is, the reinforcing roll drive system was used.

In such a four-high rolling mill, when the pattern pattern provided on the upper work roll 31 is transferred to the rolled plate material by rolling the rolled plate material 49, a highly accurate pattern pattern can be obtained. In other words, the work roll was cooled during rolling, but even when the roll surface temperature changed in the range of about 50 to 200 ° C., a good pattern pattern with good precision could be stably obtained. . In addition, since it is made of ceramics, it has excellent wear resistance, and printing and rolling can be performed stably for a long period of time. Furthermore, seizure hardly occurs, and there are few rolling accidents due to seizure, and stable rolling can be performed for a long period of time.

The work roll used in this embodiment has a step of 0.1 μm or more on the rolled surface of its body. That is, there is a step of 0.12 to 0.14 mm here. Generally, when such a step exists, a seizure phenomenon occurs more frequently than a smooth surface, and rolling is interrupted. However, in this embodiment, since the body surface of the work roll is formed of ceramics, the seizure phenomenon can be significantly suppressed, and stable rolling can be performed for a long period of time.

As a result of rolling with the character pattern ROLL, the curved part (circle part), the straight part, the intersection part, the corner part and the like were well transferred, and the outline of each part was clearly transferred. In the present embodiment, the concave groove is described, but the same applies to the convex protrusion.

Next, a case where the present invention is applied to a six-high rolling mill will be described.

The six-high rolling mill shown in FIG.
7, an upper work roll 31 and a lower work roll 32 for rolling a plate, and an upper work roll 31 and a lower work roll 32
Upper intermediate roll 33 which is a support roll for supporting
And an upper reinforcing roll 35 that supports the upper intermediate roll 33 and the lower intermediate roll 34.
And a lower reinforcing roll 36 are provided. In the present embodiment, the ceramic roll 1 in which the character pattern is formed on the body surface is applied to the upper work roll 31. And
The lower work roll 32 was a ceramic roll having no character pattern formed on the body surface. The shafts of the upper work roll 31 and the lower work roll 32 are rotatably supported by a bearing 41 for the upper work roll and a bearing 42 for the lower work roll, respectively. , Each bearing for upper intermediate roll 4
3 and the lower intermediate roll bearing 44 so as to be rotatable, and the shaft portions of the upper reinforcing roll 35 and the lower reinforcing roll 36 are rotatably supported by the upper reinforcing roll bearing 45 and the lower reinforcing roll bearing 46, respectively. .

The rolling load is applied to the rolled sheet material 49 from the upper work roll 31 via the upper reinforcing roll 35 and the upper intermediate roll 33 by the rolling device 48 attached to the housing 47. In the rotary drive mechanism of the present embodiment, the upper work roll 31 and the lower work roll 32 are made of ceramics having poor rigidity, and have a small diameter, so that the work rolls are not driven directly but indirectly. That is, the intermediate roll driving system was used.

The upper work roll 31 and the lower work roll 32 are provided with work roll benders 52, respectively, and the upper intermediate roll 33 and the lower intermediate roll 34 are provided with intermediate roll benders 50 and 51, respectively. Was. That is, the upper intermediate roll 33 and the lower intermediate roll 34 can be provided with positive and negative bender forces.

In such a six-high rolling mill, when the pattern pattern provided on the upper work roll 31 is transferred to the rolled sheet material by rolling the rolled sheet material 49, a highly accurate pattern pattern can be obtained. In other words, the work roll was cooled during rolling, but even when the roll surface temperature changed in the range of about 50 to 200 ° C., a good pattern pattern with good precision could be stably obtained. . In addition, since it is made of ceramics, it has excellent wear resistance, and printing and rolling can be performed stably for a long period of time. Furthermore, seizure hardly occurs, and there are few rolling accidents due to seizure, and stable rolling can be performed for a long period of time.

In the present embodiment, a four-high rolling mill or a six-high rolling mill is shown, but the present invention can be applied to other rolling mills such as other high rolling mills.

As described above, according to the present embodiment, the following effects can be obtained.

(1) The surface of the body of the work roll has at least one of a concave groove and a projection, and the surface of the body has a thermal expansion coefficient of 1.0 to 10.0 × 10 ^-6 . In some cases, a geometric pattern, a decorative pattern, or the like can be accurately transferred onto the surface of a rolled sheet material.

(2) In a work roll for rolling, a roll surface is formed on the body surface of the work roll by providing at least one of a concave groove portion and a convex protrusion portion, and the roll surface is made of ceramics. Thereby, a geometric pattern, a decorative pattern, or the like can be accurately transferred onto the surface of the rolled sheet material. Further, rolling (printing) for stable transfer for a long period of time can be performed.

(3) Since the depth of the concave groove or the height of the convex protrusion is 10 μm or more, the boundary of the transferred (printed) geometric pattern or decorative pattern is clearly distinguished. It is possible to transfer a pattern with clear dimensional accuracy.

(4) In a ceramic roll for rolling, at least one of a concave groove portion and a convex protrusion portion is formed on the surface of the body of the ceramic roll, so that a geometric pattern or decoration is formed on the surface of the rolled sheet material. Patterns and the like can be accurately transferred. Further, rolling (printing) for stable transfer for a long period of time can be performed.

(5) After sintering, at least one of the concave groove portion and the convex protrusion portion is formed on the surface of the body of the ceramic roll by a shot blast method.
A concave groove or a convex protrusion can be accurately formed on the surface of the ceramic roll. (6) In a rolling mill having upper and lower work rolls for rolling and a support roll for supporting the upper and lower work rolls, at least one body surface of the upper and lower work rolls is made of ceramic, and a concave groove is formed on the body surface. By forming at least one of the projections and the projections, it is possible to obtain a rolling mill that transfers a geometric pattern, a decorative pattern, or the like to the surface of a rolled plate with high accuracy.

(Embodiment 2) Groove processing step 16 of Embodiment 1
Example 1 using a SiC abrasive having an average particle size of 90 μm while rotating the roll by the shot blast method in Example 1.
Shot blasting was performed by taking 12.5 times the processing time as compared with. Then, as a result of removing the dry film with methyl ethyl ketone, a deep groove of 1.50 to 1.52 mm could be formed in the pattern portion where the shot was applied.

As the pattern, a pattern as shown in FIG. 8 was formed. FIG. 8 is a roll development diagram in which a pattern is formed. In the present embodiment, the concave groove portion 9 indicated by the black portion was formed at a low step, and the other body surface was the mirror surface portion 8 which was finished and polished to a mirror surface. Of course, they may be formed in reverse depending on the desired pattern. For example, the step indicated by the black portion may be raised as a convex protrusion, and the surface of the other body may be lowered by shot processing.

When this roll was used as a work roll of a rolling mill in which the work roll was rotated by the rotation of an intermediate roll to perform rolling, a pattern due to unevenness of the step could be formed on the rolled material.

It should be noted that the ceramic roll 1 manufactured by the working of Examples 1 and 2 is used for a long period of time with little wear because the ceramics have essentially high hardness and wear resistance. Can be. Also, 1.5
Even if a step of 0 to 1.52 mm was formed, it was found that the seizure phenomenon hardly occurred and the seizure resistance was excellent.

As described above, according to the present embodiment, a geometric pattern or a decorative pattern can be clearly printed on a rolled material, and the geometric pattern or the decorative pattern can be formed by a step of the rolled material. Since the ceramic roll has high hardness and wear resistance, it can be used for a long period of time.

[0078]

According to the ceramic roll of the present invention,
There is an effect that a geometric pattern, a decorative pattern, or the like can be accurately transferred onto the surface of the rolled sheet material.

According to the method for manufacturing a ceramics roll of the present invention, there is an effect that a concave groove can be accurately formed on the surface of the ceramics roll.

According to the rolling mill of the present invention, there is an effect that a geometric pattern or a decorative pattern or the like can be accurately transferred onto the surface of a rolled sheet material.

[Brief description of the drawings]

FIG. 1 is a sectional view of a ceramic roll according to an embodiment of the present invention.

FIG. 2 is a development view of a ceramic roll body portion according to one embodiment of the present invention.

FIG. 3 is a manufacturing process diagram of a ceramic roll according to an embodiment of the present invention.

FIG. 4 is an enlarged sectional view of a concave groove portion in a process of manufacturing a ceramic roll according to an embodiment of the present invention.

FIG. 5 is a diagram showing a thermal expansion effect of a ceramics roll according to an embodiment of the present invention.

FIG. 6 shows a four-high rolling mill according to an embodiment of the present invention.

FIG. 7 shows a six-high rolling mill according to an embodiment of the present invention.

FIG. 8 is a development view of a ceramic roll body portion according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Ceramic roll, 2 ... Metal cap, 3 ... Center hole, 4 ... Metal pipe, 5 ... Small diameter part, 6 ... Escape part, 7 ... Through-hole, 8 ... Mirror surface part, 9 ... Concave groove part, 11 ...
Granulation process, 12: compacting process, 13: sintering process, 14
... Shaft part forming step, 15 ... Body part polishing step, 16 ... Groove part processing step, 20 ... Dry film, 21 ... Original film, 3
1 upper work roll, 32 lower work roll, 33 upper intermediate roll, 34 lower intermediate roll, 35 upper reinforcement roll, 3
6 ... Lower reinforcing roll, 41 ... Bearing for upper work roll, 42 ...
Bearing for lower work roll, 43 ... Bearing for intermediate roll, 44 ...
Bearing for lower intermediate roll, 45 ... Bearing for upper reinforcing roll, 46
... bearings for lower reinforcing rolls, 47 ... housing, 48 ... press-down devices, 49 ... rolled plate materials, 50, 51 ... bender devices for intermediate rolls.

Claims (7)

[Claims] 1. A work roll for rolling, wherein the surface of the body of the work roll has at least one of a concave groove and a projection, and the coefficient of thermal expansion of the surface of the body is 1.0.
A work roll having a size of from 10.0 to 10 ^-6 . 2. A work roll for rolling, wherein at least one of a concave groove portion and a convex protrusion portion is provided on a body surface of the work roll to form a rolled surface, and the rolled surface is made of ceramics. The work roll that is the feature. 3. The work roll according to claim 1, wherein a depth of the concave groove or a height of the convex protrusion is 10 μm or more. 4. A ceramic roll for rolling, wherein at least one of a concave groove portion and a convex protrusion portion is formed on the body surface of the ceramic roll. 5. The ceramic roll according to claim 4, wherein the depth of the concave groove or the height of the convex protrusion is 10 μm or more. 6. A method of manufacturing a ceramic roll for rolling, wherein after sintering, at least one of a concave groove portion and a convex protrusion portion is formed on a surface of a body portion of the ceramic roll by a shot blast method. Method for producing a ceramic roll. 7. A rolling mill having upper and lower work rolls for rolling and a support roll for supporting the upper and lower work rolls,
A rolling mill, wherein at least one of the upper and lower work rolls is made of ceramic and at least one of a concave groove and a convex is formed on the surface of the body.