JP2001234924A - Bearing and roll shaft for molten plating device and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent vibrations even when used in a molten plating bath under a severe condition, to ensure high reliability, and to enable a low frictional coefficient and a long life, in a sliding bearing slidably supporting a roll shaft by a ceramic member. SOLUTION: A bearing bush main body 8 is shaped in a cylinder, and a plurality of columnar ceramic members 9 matched at an axis center is fitted with on a circle in a pitch diameter DP in an inner diameter side at even intervals. Each columnar ceramic member 9 is fitted with at an arrangement where a side surface is projected out by projecting height (h) from the inner peripheral surface of the bearing bush 8. Shrinkage fitting which makes the inserted columnar ceramic members 9 have no clearance at a plating bath temperature when using a bearing is effective. Columnar ceramic members 13 split in an axial direction in advance is fitted with, thereby dispersing a load and bending stress to prevent breakage, or preventing complete damage so as not to develop to the whole part if breakage is caused.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing and a roll shaft for a hot-dip plating apparatus for improving the life and sliding function of a bearing portion such as a sink roll which comes into rotation contact with a steel strip in a hot-dip metal plating bath, and its manufacture. About the method.

[0002]

2. Description of the Related Art Generally, a metal member used in a hot-dip metal plating bath is easily melted by the plating bath, and particularly, a sliding portion of a bearing is severely melted to shorten a shaft life. Conventionally, in order to prevent such erosion and extend the life of the shaft, a ceramic is further formed on the metal surface by using stainless steel as a metal member, and in recent years, Japanese Patent Application Laid-Open Nos. JP-A-5-44002, JP-A-7-4256
As disclosed in Japanese Patent Application Publication No. 2 (1993) -207, a method of attaching ceramic as a sliding member to a metal member has been put to practical use.

On the other hand, as shown in Japanese Patent Application Laid-Open No. 60-84423, a plurality of cylindrical sliding member segments formed in a columnar shape are arranged at equal intervals on the inner peripheral surface of a fixed side case of a slide bearing. Also, there has been proposed a sliding bearing having a configuration in which shrink fitting is inserted so that only the sliding surface is projected.

[0004]

However, when ceramic is attached to a metal member as a sliding member, the life of the shaft can be partially extended, but the structure for attaching to the metal member is not appropriate. Sliding parts were damaged by sludge and the like, and ceramics were suddenly damaged due to uneven strength of the pressed ceramics, so that there were problems such as lack of reliability.

[0005] Further, there is a proposal to provide a fluid lubrication condition by combining a boride-based ceramic having good wettability. However, since it is structurally in surface contact, it is difficult for the material to be easily scratched due to local load or the like involving sludge or the like. Inevitably, sufficient breakage resistance of the ceramic, long shaft life, and low friction coefficient have not been obtained.

The sliding bearing disclosed in Japanese Patent Application Laid-Open No. 60-84423 has a structure in which a ceramic cylinder is shrink-fitted to a metal member, and the shaft is slidably supported by structural line contact.
Since it is a shrink fit that is only fixed for use at room temperature or in water, severe conditions in molten metal such as in a plating bath (the possibility of entrainment of high-hardness sludge at a high temperature of 480 ° C or higher) Condition) is not considered.

[0007] Specifically, the ceramic cylinder tends to come off due to thermal expansion of the metal member due to use under high temperature, and the ceramic cylinder in the bearing may be subjected to local load or bending due to thermal deformation of the gantry holding the bearing. There has been a problem that the wire may be broken by receiving stress, or sludge tends to accumulate in a gap corresponding to the height of the sliding surface, thereby increasing wear.

Further, when the bearing is used in a plating bath at a high temperature, the thermal deformation of the bearing itself progresses, so that it is difficult for the ceramic cylinder fitted and held therein to maintain a positional relationship parallel to the roll axis. That is, it does not make line contact uniformly in the axial direction but makes partial contact. As a result, play occurs at one of the free end side and the connection end side of the roll shaft by the protrusion height of the sliding surface, causing large vibrations when the roll shaft rotates.

The present invention is directed to a sliding bearing in which a roll shaft is slidably supported by a curved surface formed on a ceramic member as a sliding surface, and prevents slippage or breakage of the ceramic member even when used in a hot-dip plating bath under severe conditions. Bearings and roll shafts for hot-dip coating equipment that can reduce wear due to sludge intrusion, prevent vibration due to sliding contact without play, and have high reliability, low friction coefficient and long life. It is an object of the present invention to provide a manufacturing method thereof.

[0010]

According to the present invention, a cylindrical inner surface is formed in a bearing for a hot-dip plating apparatus for supporting a roll shaft in a hot-dip plating bath. Metal member, and a shape having a convex curved surface in a direction toward the central axis of the cylindrical inner surface in a state where a plurality of metal members are arranged in a circumferential direction of the cylindrical inner surface, and the convex curved surface is formed at a predetermined height from the surface of the cylindrical inner surface. A ceramic member fitted to the metal member so as to protrude therefrom, and fixing means for fixing the ceramic member in its axial direction.

[0011] Thus, for example, by providing the fixing means as a bearing lid for closing the insertion hole of the ceramic member, the ceramic member can stably move in the axial direction even when used in a plating bath in which the ceramic member is more easily removed than in the atmosphere. Fixation becomes possible.

(2) In order to achieve the above object, according to the present invention, in a bearing for a hot-dip coating apparatus for supporting a roll shaft in a hot-dip plating bath, a metal member having a cylindrical inner surface and a cylindrical member are provided. The metal has a shape having a convex curved surface in a direction toward the central axis of the cylindrical inner surface in a state where a plurality of the convex inner surfaces are arranged in the circumferential direction of the cylindrical inner surface, and the convex curved surface protrudes to a predetermined height from the surface of the cylindrical inner surface. A ceramic member fitted to the member is provided, and the fitting of the ceramic member to the metal member is performed by shrink-fitting so that the gap with the metal member becomes zero at the plating bath temperature during use.

Thus, even in the use in a plating bath in which the temperature of the ceramic member is higher than that in the air and the ceramic member is easy to come off, the gap is reliably zero so that the ceramic member can be stably fixed.

(3) In order to achieve the above object, according to the present invention, in a bearing for a hot-dip coating apparatus for supporting a roll shaft in a hot-dip plating bath, a metal member having a cylindrical inner surface and a cylindrical member are provided. The metal has a shape having a convex curved surface in a direction toward the central axis of the cylindrical inner surface in a state where a plurality of the convex inner surfaces are arranged in the circumferential direction of the cylindrical inner surface, and the convex curved surface protrudes to a predetermined height from the surface of the cylindrical inner surface. A ceramic member fitted to the member, and the ceramic member is divided into a plurality in the axial direction.

Thus, the local load and bending stress applied to the ceramic member in the bearing due to the thermal deformation of the gantry holding the bearing can be dispersed, and the reliability and the life of the ceramic member can be improved.

(4) In order to achieve the above object, according to the present invention, in a bearing for a hot-dip coating apparatus for supporting a roll shaft in a hot-dip plating bath, a metal member having a cylindrical inner surface and a cylindrical member are provided. A plurality of cylindrical inner surfaces are arranged in the circumferential direction, and the shape of the cross section orthogonal to the central axis direction of the cylindrical inner surface is circular, and fitted to a metal member so as to protrude to a predetermined height from the surface of the cylindrical inner surface. A ceramic member to be combined, wherein the protrusion height of the ceramic member is more than 0 and 5 mm or less,
The spacing distance between the ceramic members adjacent in the circumferential direction of the cylindrical inner surface is １ ／ or more of the diameter of the ceramic members, and the spacing angle is 90 ° or less.

[0017] Thus, since the protrusion height of the ceramic member is more than 0 and not more than 5 mm, it is possible to prevent a change in the friction coefficient due to sludge, and a damage and a decrease in strength of the ceramic member. Further, since the distance between adjacent ceramic members is at least 1/3 of the diameter of the ceramic members, the ceramic members are firmly held by the metal members, and the distance between adjacent ceramic members is 90 ° or less. Accordingly, the support of the roll shaft is stabilized, so that vibration during high-speed rotation can be suppressed.

(5) In order to achieve the above object, according to the present invention, in a method for producing a bearing for a hot-dip plating apparatus for supporting a roll shaft in a hot-dip plating bath, a cylindrical inner surface is formed on a metal member. Forming a convex curved surface on the ceramic member, arranging a plurality of ceramic members in the circumferential direction of the cylindrical inner surface, and shrink-fitting the metal member such that the convex curved surface protrudes to a predetermined height from the surface of the cylindrical inner surface; It is assumed that shrink fitting is performed in a temperature range of 20 ° C. to 100 ° C. higher than the use temperature of the plating bath.

Thus, even in the use in a plating bath where the temperature of the ceramic member is higher than that in the air and the ceramic member is easy to come off, the gap is reliably zero, and the ceramic member can be stably fitted.

(6) In order to achieve the above object, according to the present invention, in a bearing for a hot-dip coating apparatus for supporting a roll shaft in a hot-dip plating bath, a metal member having a cylindrical inner surface and a cylindrical member are provided. It has a shape having a convex curved surface in a direction toward the central axis of the cylindrical inner surface in a state where a plurality of the curved inner surfaces are arranged in a circumferential direction, and is fitted to a metal member so that a predetermined amount of the convex curved surface is embedded from the surface of the cylindrical inner surface. And a ceramic member to be combined.

In this way, in the initial stage of use, the metal member is subjected to unstable sliding due to non-uniform contact, and after continued use, the ceramic member is gradually exposed by adaptation by the rotation of the roll shaft. It enables stable sliding contact and prevents vibration.

(7) In order to achieve the above object, according to the present invention, in a bearing for a hot-dip coating apparatus for supporting a roll shaft in a hot-dip plating bath, cylindrical ceramic members are juxtaposed and fixed on the same plane. It is assumed that a plurality of sliding contact plates are used, and the sliding direction of each ceramic member on each sliding contact plate is orthogonal to the axial direction of one roll shaft.

Thus, even if the positional relationship between the ceramic member and the roll shaft cannot be maintained in parallel due to the thermal deformation of the sliding contact plate, vibration can be prevented without causing backlash.

(8) In order to achieve the above object, according to the present invention, in a roll shaft for a hot-dip coating apparatus supported by a bearing in a hot-dip plating bath, a roll-shaft main body formed in a cylindrical shape; It has a convex curved surface in the direction from the center axis of the cylindrical side surface to the outer periphery in a state where a plurality of cylindrical side surfaces are arranged in the circumferential direction, and the convex curved surface protrudes to a predetermined height from the surface of the cylindrical side surface And a ceramic member fitted to the roll shaft main body.

Thus, unlike the bearings described in the above (1) to (7), only the specific ceramic member is worn depending on the direction of the load applied to the roll shaft. Since all the ceramic members arranged in a plurality of directions wear uniformly, a stable sliding contact is possible and vibration can be prevented.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. First, FIG. 1 is a schematic configuration diagram of a general hot-dip plating apparatus 1 to which the bearing for a hot-dip plating apparatus of the present invention is applied. In this figure, a steel strip 2 delivered from an annealing furnace (not shown) is immersed in a plating bath 4 containing molten metal 3, and its direction is changed and supported by a sink roll 5, a collect roll 6, and a stabilizer roll 7. It is configured to be pulled up from the plating bath 4 later. These rolls are configured to rotate while receiving a load in a certain direction by contacting the steel strip 2 during operation of the apparatus. The bearing of the present invention is applied to a bearing that supports the roll shafts of these rolls that rotate while being immersed in the plating bath 4 as described above.

FIG. 2 is a front sectional view (a) and a side sectional view (b) of the bearing bush portion 8 of the hot-dip coating apparatus bearing according to the first embodiment of the present invention. In this figure, the bearing bush 8 body is a metal member located outside diameter D _B, inner diameter d _B, a cylindrical shape having a width W, were matched with the axial center on the circle in the pitch diameter D _P of the inner diameter closer A plurality of ceramic members are fitted at equal intervals. The ceramic member has a cylindrical shape having a diameter D _S and a length L (hereinafter, referred to as a cylindrical ceramic member 9), and is fitted in such a manner that each side protrudes from the inner peripheral surface of the bearing bush 8 by a protruding height h, and Since the length L of the cylindrical ceramic member 9 is the same as the length of the fitting hole on the bearing bush 8 side, the fitting is such that the end face positions on the insertion port side coincide with each other at the time of fitting.

Further, as one of the features of the bearing for a hot-dip plating apparatus of the present invention, the fitting of the cylindrical ceramic member 9 to the bearing bush 8 is firmly fixed by shrink fitting in a high-temperature atmosphere. In other words, shrink fitting in which the gap of the cylindrical ceramic member 9 is zero at the plating bath temperature when the bearing is used is effective. That is, the bearing bush 8
It is preferable that molten metal does not enter between the cylindrical ceramic member 9 and the cylindrical ceramic member 9.

As a means for fixing the cylindrical ceramic member 9 in the axial direction, a metal disk 10 having the same outer diameter and inner diameter as the bearing bush 8 is applied to the end surface of the bearing bush 8 on the side of the cylindrical ceramic member 9 insertion opening side, and a bolt 11 is formed. Stop and fix.

In the use of the bearing bush 8 having the above structure, the roll shaft 12 having a diameter D _R (that is, D _R = d _B -2h) that comes into contact with the side surfaces of all the cylindrical ceramic members 9 is inserted and melted. It will support sliding contact in the metal plating bath.

By adopting the above structure, the size of the ceramic component to be incorporated can be reduced and the structure can be simplified as compared with the conventional structure, and a structure can be obtained in which a simple compressive stress is applied.
Sudden breakage of the cylindrical ceramic member 9 can be prevented, and a highly reliable ceramic bearing structure can be obtained. In addition, since the roll shaft 12 is slidably supported by a plurality of line contacts, stable rotation can be obtained, and the fluid lubrication condition is easily generated by the entangled molten metal, so that the slidable support having a low friction coefficient is possible. is there.

Further, the shrink-fitting of the cylindrical ceramic member 9 will be described in detail. The cylindrical ceramic member 9 and the bearing bush 8 should be shrink-fitted in an actually used high-temperature plating bath without loosening. The shrink fitting temperature differs depending on the bath 4. At a temperature 20 ° C. to 100 ° C. higher than the temperature of the plating bath to be used, an extremely large baking such as about 1/100 of the diameter so that the outer diameter of the cylindrical ceramic member 9 and the fitting hole diameter of the bearing bush 8 become the same. Perform at the fitting cost. For example, zinc has a bath temperature of about 470 ° C. and thus has a temperature range of about 490 ° C. to 570 ° C., and galvaluium has a bath temperature of about 600 ° C. and has a bath temperature of about 6 ° C.
By shrink fitting so that the outer diameter of the cylindrical ceramic member 9 and the fitting hole diameter of the bearing bush 8 become the same size in a temperature range of 20 ° C. to 700 ° C., it can withstand use in a plating bath under severe conditions. It will be.

Although a large number of stainless steel materials are used for the bearing bush 8 as a metal member, it is effective in the present invention to subject this metal member to a boring treatment as a measure against erosion. It is effective to use a silicon nitride-based or boride-based material for the cylindrical ceramic member 9. The former has a difference that it is difficult to get wet with molten metal, and the latter has a difference that it is easy to get wet. However, both have high strength (bending strength: 500 MPa or more), have melting resistance to molten metal, and have high sliding strength due to high high-temperature strength. I have.

FIG. 3 shows a cylindrical ceramic member 9 to be fitted.
FIG. 6 is a diagram for explaining the relationship between the number of vibrations and the magnitude of initial vibration. The test conditions were as follows: roll shaft diameter D _R = 60 mm, load P =
The weight was set to 500 kgf, and a comparative study was performed on the number of the cylindrical ceramic members 9 fitted to the bearing bush 8 on one half of the half mold. As can be seen from the figure, in order to obtain a stable rotation, the line contact between the roll shaft 12 and the cylindrical ceramic member 9 must be at least three times.
It is necessary to have more than books. In addition, even when the operating load is high, it is effective to disperse the load by adopting a configuration having a large number of line contacts, in addition to increasing the outer diameter of the cylindrical ceramic member 9 to increase the contact width.

Further, the gantry holding the bearing bush 8 having the above structure is heated to a high temperature in the plating bath, so that it is liable to be thermally deformed. Therefore, bending stress is applied to the cylindrical ceramic member 9 fixed inside, and breakage and local wear are often observed. As a countermeasure, as shown in FIG. 4, by fitting a cylindrical ceramic member 13 divided in advance in the axial direction, load and bending stress are dispersed to prevent breakage, and even if it is broken, it does not progress to the whole. An arrangement for preventing total loss is effective.

FIG. 5 is a diagram for explaining a comparison of the wear of the shaft sleeve between when the divided cylindrical ceramic member 13 is used and when the integrated cylindrical ceramic member 9 is used. In addition, the test conditions were compared using a cylindrical ceramic member having a diameter D _S = 25 mm and a length L = 100 mm using an integral type and divided into two equal parts and three equal parts. In addition, the roll shaft diameter D _R =
80mm, number of rotations = 100rpm, load P = 1000k
gf, Zn + 0.15Al plating bath component, bath temperature = 4
70-490 ° C.

As shown in the figure, it can be seen that the cylindrical ceramic member 13 divided into a large number at the beginning of rotation has a smaller wear amount. However, after a certain period of time, the shape of the roll shaft 12 wears and adapts to the shape of the bearing bush 8 to a certain extent, so that the load distribution becomes uniform, so that the progress of wear of the integral type and the split type becomes almost equal.

As a result, the greater the number of divisions of the cylindrical ceramic member 9 in the axial direction, the smaller the amount of abrasion. However, if the length is too short, the crushing strength is weakened and the member is easily damaged. Therefore, it is preferable that the division length is at least as short as its diameter. Accordingly, a configuration in which the spherical ceramic member 14 is fitted as shown in FIG. 6 is also effective.

Regarding the outer shape of the bearing bush, there is no particular difference in function and performance between the cylindrical type 8 as in the first embodiment shown in FIG. 2 and the prism type 15 as shown in FIG. There is no problem in function even if the half mold 16 is divided in the axial direction as shown in FIG. Rather, it has been found that the half mold 16 generates less molten metal sludge.

FIG. 9 is a view for explaining the effect on the amount of wear of the roll shaft sleeve by increasing or decreasing the gap between the outer surface of the roll shaft sleeve and the inner peripheral surface of the bearing bush 8, that is, the height h of the protrusion of the cylindrical ceramic member 9. It is. The test conditions were as follows: cylindrical ceramic members having a diameter D _S = 25 mm and a length L = 100 mm were arranged at regular intervals of a distance S = 10 mm, and in addition, a roll shaft diameter D _R = 80 mm and a rotation speed = 1
00 rpm, load P = 1000 kgf, plating bath component Zn + 0.15Al, bath temperature = 470-490 ° C. And increase or decrease the gap (protrusion height) h by changing the internal diameter d _B of the bearing bush, and intended to measure the wear amount corresponding thereto.

As shown in the figure, it can be seen that the abrasion increased when the gap h exceeded 6 mm. This is because sludge accumulates in this gap, and the wear increases due to its action. However, since the form of the sliding contact is line contact to the last, there is no increase in the coefficient of friction, and the function as a bearing does not decrease much.

As described above, by setting the protrusion height h of the cylindrical ceramic member 9 to be more than 0 and 5 mm or less, the accumulation of sludge is small, and the molten metal easily passes between the roll shaft surface and the cylindrical ceramic member 9. As a result, the condition of fluid lubrication can be easily achieved, and it is possible to prevent the fluctuation of the friction coefficient due to the sludge, the damage of the cylindrical ceramic member 9 and the decrease in strength.

[0043] Also with respect to the arrangement of the circumferential direction of the cylindrical ceramic member 9 of the cylindrical inner surface, the spacing distance S of the cylindrical ceramic member 9 adjacent the at least 1/3 of the diameter D _S of the cylindrical ceramic member 9 itself As a result, the structure of the metal member for firmly holding the cylindrical ceramic member 9 is secured, and the interval angle A between the adjacent cylindrical ceramic members 9 is set to 9
By setting the angle to 0 ° or less, the surface of the roll shaft 12 is brought into line contact with the plurality of cylindrical ceramic members 9, and more stable sliding contact support can be performed, so that vibration during high-speed rotation can be suppressed.

Next, FIG. 10 is a front sectional view (a) and a side sectional view (b) of a state in which the roll shaft 12 is inserted into the bearing bush 17 of the bearing for a hot-dip plating apparatus according to the second embodiment of the present invention. is there. In this figure differs from the bearing bush 8 of the first embodiment, a clearance fit to the extent that a first mold half the inner diameter d _B of the bearing bush 17 can slidably contact the outer diameter D _R of the roll shaft 12 located possible dimensions, also in the configuration in which the cylindrical ceramic member 9 by a certain increase slightly pitch diameter D _P is embedded without protruding from the inner circumferential surfaces of all the bearing bush 17.

With this configuration, in the initial stage of use, the metal member is subjected to unstable sliding due to non-uniform contact, and after continued use, the cylindrical ceramic member 9 is adapted by rotation of the roll shaft. Is gradually exposed to provide stable sliding contact. Therefore, even when the bearing bush 17 cannot maintain the positional relationship between the cylindrical ceramic member 9 and the roll shaft 12 in parallel due to thermal deformation, vibration can be prevented without rattling. The embedding depth h 'of the cylindrical ceramic member 9 from the inner peripheral surface of the bearing bush 17 is preferably about 0 to 2 mm in consideration of the familiarity of the rotation of the roll shaft.

Next, FIG. 11 shows the same as in the second embodiment.
It is the front sectional view (a) and the side sectional view (b) of the bearing bush 18 part of the bearing for the hot-dip plating apparatus which was constituted for use in a high-temperature plating bath in a third embodiment of the present invention. In this figure, the bearing bush 18 is roughly in the form of a V-block, and a plurality of cylindrical ceramic members 9 are juxtaposed on both V-slopes so as to be arranged along the vertical direction of the slope. The fitting is performed such that the side surface protrudes by h. And this bearing bush 1
When using the cylindrical ceramic member 9 on both slopes
Roll shaft 1 in the outer diameter D _R of the sides can abut size of
2 will be used.

With this configuration, even when the bearing bush 18 cannot maintain the positional relationship between the cylindrical ceramic member 9 and the roll shaft 12 in parallel due to thermal deformation, the stability of the cylindrical ceramic member 9 with respect to the roll shaft 12 can be maintained. In this way, it is possible to suppress the vibration during high-speed rotation.

As described above, since a load is always applied to each roll provided in the plating bath only in a fixed direction, the bearing bush 18 is also partially configured in the circumferential direction (merely V block). The number of slopes for slidingly supporting the roll shaft 12 is not limited to two, but may be configured to slide and support three or more.

FIG. 12 is a front sectional view (a) and a side sectional view (b) of a roll shaft 19 for a hot-dip plating apparatus according to the present invention. In this figure, the roll shaft 19 body outer diameter D _R, is in the cylindrical shape having a width W, a plurality of cylindrical ceramic member 9 to match the respective axes centered on the circle in the pitch diameter D _P of the inner diameter closer They are fitted at equal intervals. The cylindrical ceramic member 9 has a cylindrical shape having a diameter D _S and a length equal to the width W of the roll shaft 19 main body, and each of the side surfaces protrudes from the outer peripheral surface of the roll shaft 19 main body by a protruding height h ″. The fitting is in place.

[0050] Then, in the use of the roll shaft 19 in the above structure, in contact with the side surface of all of the cylindrical ceramic member 9 fitting the entire roll shaft 19 inside diameter d _B (i.e. d _B =
(D _R + 2h), and is slid in the molten metal plating bath.

With this configuration, unlike the configuration in which only a specific ceramic member is worn depending on the direction of the load applied to the roll shaft 12 when the other bearing is used, the roll shaft 19 of this embodiment Since all the plurality of cylindrical ceramic members 9 arranged in the circumferential direction of the roll shaft 19 main body are uniformly worn, stable sliding contact is possible and vibration can be prevented.

Specific examples of the bearings for the hot-dip coating apparatus of the first and second embodiments described above will be shown below, and their functions and effects will be described based on test results.

[0053]

[Embodiment 1] First, this embodiment is the first embodiment.
Model of approximately the same size as the actual
And verify its function. Each dimension in Fig. 2
As a rule, the bearing bush is made of stainless steel
Type D _B= 220mm, inner diameter d_B= 120 mm, width W = 13
0mm cylindrical shape and pitch diameter D_P= 160m
8 cylindrical ceramics at equal intervals of 45 ° on the circumference of m
A fitting hole is drilled so that the members can be fitted. Column
The ceramic member is made of Sialon and has a diameter D_S= 3
0mm, L = 100mm cylindrical shape
The fitting hole of the bush is also drilled at a depth of 100 mm. Shrink fit
In some of the eight cylindrical ceramic members
At room temperature, the other in a 500 ° C temperature atmosphere,
The outer diameter of the mic member and the fitting hole diameter of the bearing bush are the same.
As shown in the figure, the fitting at 500 ° C is 1/100 of the diameter.
Is an interference fit with an extremely large fitting allowance.

Then, as a result of returning to room temperature after shrink fitting, no damage such as cracks or cracks was found in the cylindrical ceramic member, and the end face on the insertion port side was covered with a stainless steel plate and fixed with bolts. Bearing bush was manufactured. In addition, the produced bearing bush was subjected to a boring treatment (900 ° C. × 8 hours) for imparting erosion resistance of metal, but there was no problem.

These bearing bushes were set at 470 ° C. to 500
After performing the immersion test in the Zn bath at 5 ° C. five times, the fitting portion was verified. No particular problem was found at the shrink fitting portion, but the Zn bath penetrated into the portion inserted at room temperature. . In the case of long-term use, this may cause a local drop of the inner surface of the hole. The penetration of the Zn bath is less in the fitting portion at 500 ° C. than in the normal temperature fitting, and it can be used stably for a long time.

[Example 2] In this example, the model of the first embodiment was manufactured and tested on an actual machine. The dimensions were the same as those in Example 1 described above, and the shrink-fitting temperature of the cylindrical ceramic member was also set at 500 ° C. However, the cylindrical ceramic member is of a two-part type to prevent breakage due to local load, and the height h of the cylindrical ceramic member protruding from the inner peripheral surface of the bearing bush is determined by fluctuations in the friction coefficient due to accumulated sludge and damage to the cylindrical ceramic member. The thickness was set to 2 mm in consideration of prevention. The materials of the cylindrical ceramic member and the bearing bush were Sialon and SUS316L, respectively. The manufactured bearing bush was subjected to a boring treatment (90
0 ° C. × 8 hours). The sleeve on the roll side to be slid was fitted with a Co-Cr-W sprayed sleeve on the surface of SUS316L, and the slide was a combination of sialon and sprayed.

When a conventional bearing is used in a hot-dip Zn plating bath, it is generally sufficient to endure for about 2 weeks to about 20 days. However, in the case of the bearing of the present embodiment, it can be used for one month, and the bearing bush and the cylinder can be used. Good performance results were obtained without damage such as cracking or chipping of the ceramic member.

[Embodiment 3] In this embodiment, a material was produced by changing the material of the above-mentioned Embodiment 2, and a trial use for an actual machine was performed. The dimensions, shrink fitting temperature, and other structures and surface treatments were the same as those in Example 2 above. Only the materials of the cylindrical ceramic member and the roll shaft sleeve were changed to TiB ₂ and Sialon, and the sliding was performed using a combination of Sialon and TiB ₂ . did. The results of use in the hot-dip Zn plating bath endured one month of use, and good performance results were obtained without damage such as cracking or chipping of the bearing bush or the cylindrical ceramic member.

[Embodiment 4] This embodiment was manufactured by changing the shrink fitting temperature of the above-mentioned Embodiment 2 and was used as a trial for an actual machine. The dimensions, materials, and other structures and surface treatments were the same as in Example 2 above. Only the shrink fitting temperature for all the cylindrical ceramic members was 750 ° C., and the outer diameter of the cylindrical ceramic members and the fitting hole diameter of the bearing bush were the same. It was made to become. About 700
The results of use in a hot-dip Al plating bath at a temperature of 1 ° C. endured one month of use, and good performance results were obtained without damage such as cracking or chipping of the bearing bush or the cylindrical ceramic member.

Example 5 In this example, a trial was performed on an actual machine in order to confirm the effects of the second embodiment. Pitch diameter of the arrangement of the cylindrical ceramic member inner diameter d _B of the bearing bush as almost the same as the outer shape D _R of the roll shaft D _P = 161 mm
The dimensions were the same as in Example 1 except for the above, and the shrink fitting of the cylindrical ceramic member was performed at the same 500 ° C. so that the outer diameter of the cylindrical ceramic member and the fitting hole diameter of the bearing bush were the same.

The cylindrical ceramic member was divided into two parts to prevent breakage due to local load. The embedding depth of the cylindrical ceramic member with the inner circumferential surface of the bearing bush is approximately 0.5mm by a pitch diameter D _P and 1mm larger than the size of the first embodiment. The materials of the cylindrical ceramic member and the bearing bush are Sialon and S, respectively.
US316L. The manufactured bearing bush was subjected to a boring treatment (holding at 900 ° C. × 8 hours) in the same manner as in Example 1 above. SUS316 for the roll side shaft that slides
A sleeve subjected to Co-Cr-W spraying was fitted on the surface of L, and sliding was a combination of sialon and spraying.

The result of use in a molten Zn bath is that it can be used for one month, and good results such as breakage and breakage of the bearing bush and the cylindrical ceramic member can be obtained. The vibration is 1/5 as compared with the embodiment.
The results were as follows, and the sliding was stable throughout.

[0063]

According to the present invention, for example, by providing the fixing means as a bearing lid for closing the insertion hole of the ceramic member,
Even when the ceramic member is used in a plating bath in which the ceramic member is more likely to come off than in the atmosphere, the ceramic member can be stably fixed in the axial direction.

Further, according to the present invention, even when the ceramic member is used in a plating bath in which the temperature is higher than that in the air and the ceramic member is easy to come off, the gap is reliably zero so that the ceramic member can be stably fixed. Become.

Further, according to the present invention, local load and bending stress applied to the ceramic member in the bearing due to thermal deformation of the gantry holding the bearing can be dispersed, and the reliability and the life of the ceramic member can be improved. It becomes possible.

Further, according to the present invention, since the protrusion height of the ceramic member is more than 0 and 5 mm or less, it is possible to prevent fluctuation of the friction coefficient due to sludge and damage / reduction of strength of the ceramic member. Further, since the distance between adjacent ceramic members is at least 1/3 of the diameter of the ceramic members, the ceramic members are firmly held by the metal members, and the distance between adjacent ceramic members is 90 ° or less. Accordingly, the support of the roll shaft is stabilized, so that vibration during high-speed rotation can be suppressed.

Further, according to the present invention, the ceramic member can be stably fixed even when used in a plating bath which is at a higher temperature than in the air and from which the ceramic member is easily removed.

Further, according to the present invention, even when used in a plating bath in which the temperature of the ceramic member is higher than that in the air and the ceramic member is easily removed, stable shrink-fitting of the ceramic member having no gap can be surely performed. .

Further, according to the present invention, in the initial stage of use, the metal member is subjected to unstable sliding due to non-uniform contact, and after continued use, the cylindrical ceramic member is removed by the familiarity of the roll shaft rotation. It is gradually exposed to allow stable sliding contact and vibration can be prevented.

According to the present invention, even when the bearing bush cannot maintain the positional relationship between the cylindrical ceramic member and the roll shaft in parallel due to thermal deformation, vibration can be prevented without rattling.

Further, according to the present invention, unlike a configuration in which only a specific ceramic member is worn by the direction of a load applied to the roll shaft as in the case of a bearing, a plurality of ceramic members are arranged in the circumferential direction of the cylindrical side surface. Since all the cylindrical ceramic members are configured to be uniformly worn, stable sliding contact is possible and vibration can be prevented.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a general hot-dip plating apparatus to which a bearing for a hot-dip plating apparatus of the present invention is applied.

FIG. 2 is a front sectional view (FIG. 2a) and a side sectional view (FIG. 2b) of a bearing bush portion of the hot-dip plating apparatus bearing according to the first embodiment of the present invention.

FIG. 3 is a diagram illustrating the relationship between the number of cylindrical ceramic members and the magnitude of initial vibration.

FIG. 4 is a side sectional view of a bearing bush portion in which a cylindrical ceramic member divided in the axial direction is fitted.

FIG. 5 is a diagram illustrating a comparison of wear of a shaft sleeve when a divided cylindrical ceramic member is used and when an integrated cylindrical ceramic member is used.

FIG. 6 is a side sectional view of a bearing bush portion fitted with a spherical cylindrical ceramic member.

FIG. 7 is a front sectional view of a bearing bush having a prismatic outer shape.

FIG. 8 is a front sectional view of a bearing bush having a half-cylindrical outer shape.

FIG. 9 is a view for explaining the influence on the wear amount of the roll shaft sleeve due to the increase and decrease of the protrusion height h of the cylindrical ceramic member.

FIG. 10 is a front sectional view (FIG. 10a) and a side sectional view (FIG. 10b) of a bearing bush portion of a bearing for a hot-dip plating apparatus according to a second embodiment of the present invention.

FIG. 11 is a front sectional view (FIG. 11a) and a side sectional view (FIG. 11b) of a bearing bush of a bearing for a hot-dip plating apparatus according to a third embodiment of the present invention.

FIG. 12 is a front sectional view (FIG. 12a) and a side sectional view (FIG. 12b) of a roll shaft for a hot-dip plating apparatus according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Hot-dip plating apparatus 2 Steel strip 3 Hot-dip metal 4 Plating bath 5 Sink roll 6 Collect roll 7 Stabil roll 8 Bearing bush of 1st embodiment (cylindrical type) 9 Cylindrical ceramic member (integral type) 10 Metal disk 11 Bolt 12 Roll shaft 13 Cylindrical ceramic member (split type) 14 Spherical ceramic member 15 Bearing bush (square column type) 16 Bearing bush (half split type) 17 Bearing bush of the second embodiment 18 Bearing bush of the third embodiment 19 Roll according to the present invention Shaft D _B Bearing bush outer diameter d _B Bearing bush inner diameter D _P pitch diameter D _S Ceramic outer diameter D _R Roll shaft outer diameter L Length W Width S Distance between cylindrical ceramic members A Distance between cylindrical ceramic members h Inner peripheral surface Projection height from h 'Embedded depth from inner peripheral surface h''Projection height from outer peripheral surface

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Junji Sakai 7-1-1, Komikamachi, Koichi-cho, Hitachi City, Ibaraki Prefecture F-term in Hitachi Research Laboratory, Hitachi, Ltd. 3J011 AA02 BA02 BA13 SD01 4K027 AA02 AA22 AB42 AD17

Claims (16)

[Claims] 1. A bearing for a hot-dip coating apparatus for supporting a roll shaft in a hot-dip bath, wherein a metal member having a cylindrical inner surface is formed, and a plurality of metal members are arranged in a circumferential direction of the cylindrical inner surface. A ceramic member having a shape having a convex curved surface in a direction toward a central axis of the cylindrical inner surface, the ceramic member being fitted to the metal member such that the convex curved surface projects to a predetermined height from the surface of the cylindrical inner surface; Fixing means for fixing the ceramic member in the axial direction thereof. 2. A bearing for a hot-dip coating apparatus for supporting a roll shaft in a hot-dip plating bath, comprising: a metal member having a cylindrical inner surface formed therein; and a plurality of metal members arranged in a circumferential direction of the cylindrical inner surface. A ceramic member fitted to the metal member so as to have a convex curved surface in a direction toward the central axis of the cylindrical inner surface, and the convex curved surface protruding to a predetermined height from the surface of the cylindrical inner surface. A bearing for a hot-dip plating apparatus, wherein the fitting of the ceramic member to the metal member is performed by shrink-fitting so that a gap with the metal member becomes zero at a plating bath temperature during use. 3. A hot-dip coating apparatus bearing for supporting a roll shaft in a hot-dip plating bath, wherein the metal member has a cylindrical inner surface formed therein, and a plurality of the metal members are arranged in a circumferential direction of the cylindrical inner surface. A ceramic member fitted to the metal member so as to have a convex curved surface in a direction toward the central axis of the cylindrical inner surface, and the convex curved surface protruding to a predetermined height from the surface of the cylindrical inner surface. A bearing for a hot-dip plating apparatus, wherein the ceramic member is divided into a plurality in the axial direction. 4. A bearing for a hot-dip coating apparatus for supporting a roll shaft in a hot-dip plating bath, wherein: a metal member having a cylindrical inner surface formed therein; and a plurality of metal members arranged in a circumferential direction of the cylindrical inner surface. A ceramic member fitted to the metal member so as to have a convex curved surface in a direction toward the central axis of the cylindrical inner surface, and the convex curved surface protruding to a predetermined height from the surface of the cylindrical inner surface. The projecting height of the ceramic member is more than 0 and 5 mm or less, and the distance between the adjacent ceramic members in the circumferential direction of the cylindrical inner surface is 1/3 of the diameter of the ceramic member.
A bearing for a hot-dip plating apparatus, wherein the bearing is arranged at an interval angle of 90 ° or less. 5. A method of manufacturing a bearing for a hot-dip coating apparatus for supporting a roll shaft in a hot-dip plating bath, comprising: forming a cylindrical inner surface on a metal member; forming a convex curved surface on a ceramic member; A plurality of the ceramic members are arranged in a circumferential direction and shrink-fitted to the metal member such that the convex curved surface protrudes from a surface of the cylindrical inner surface to a predetermined height. ~ 100 ° C
A method for manufacturing a bearing for a hot-dip plating apparatus, comprising shrink-fitting in a high temperature range. 6. A bearing for a hot-dip coating apparatus for supporting a roll shaft in a hot-dip bath, wherein a metal member having a cylindrical inner surface is formed, and a plurality of metal members are arranged in a circumferential direction of the cylindrical inner surface. A ceramic member fitted to the metal member so as to have a convex curved surface in a direction toward the central axis of the cylindrical inner surface, and the convex curved surface is buried by a predetermined amount from the surface of the cylindrical inner surface. Features Bearings for hot dip coating equipment. 7. The bearing for a hot-dip plating apparatus according to claim 6, further comprising fixing means for fixing the ceramic member in an axial direction thereof. 8. The bearing for a hot-dip plating apparatus according to claim 6, wherein the fitting of the ceramic member to the metal member is performed so that a gap with the metal member becomes zero at a plating bath temperature during use. A bearing for a hot-dip plating apparatus characterized by being fitted and fixed. 9. The bearing for a hot-dip plating apparatus according to claim 6, wherein the ceramic member is divided into a plurality of members in the axial direction. 10. The bearing for a hot-dip plating apparatus according to claim 6, wherein the burying depth of the ceramic member is 0 to 2 mm from the surface of the cylindrical inner surface, and the interval angle is 90 ° C.
A bearing for a hot-dip plating apparatus, which is arranged as follows. 11. A bearing for a hot-dip coating apparatus for supporting a roll shaft in a hot-dip plating bath, wherein a plurality of sliding contact plates in which cylindrical ceramic members are juxtaposed and fixed on the same plane are used. Wherein the axial direction of each of the ceramic members is slidably supported in an arrangement perpendicular to the axial direction of one of the roll shafts. 12. A roll shaft for a hot-dip coating apparatus supported by a bearing in a hot-dip plating bath, wherein the roll-shaft main body formed in a cylindrical shape and a plurality of the cylindrical shaft side surfaces are arranged in a circumferential direction. A shape having a convex curved surface in a direction from the central axis of the cylindrical side surface toward the outer periphery, and is fitted to the roll shaft main body such that the convex curved surface protrudes to a predetermined height from the surface of the cylindrical side surface. A bearing for a hot-dip plating apparatus, comprising: a ceramic member. 13. The roll shaft for a hot-dip plating apparatus according to claim 12, further comprising fixing means for fixing the ceramic member in an axial direction thereof. 14. The roll shaft for a hot-dip plating apparatus according to claim 12, wherein the fitting of the ceramic member to the roll shaft main body is such that a gap with the roll shaft main body is zero at a plating bath temperature during use.
A roll shaft for a hot-dip plating apparatus, which is fixed by shrink fitting so that 15. The roll shaft for a hot-dip plating apparatus according to claim 12, wherein the ceramic member is divided into a plurality of members in the axial direction. 16. The roll shaft for a hot-dip coating apparatus according to claim 12, wherein a protruding height of the ceramic member is more than 0 and 5 mm or less, and the ceramic members adjacent to each other in a circumferential direction of the cylindrical side surface are arranged. The spacing distance is 1/3 of the diameter of the ceramic member
A roll shaft for a hot-dip plating apparatus, wherein the roll shaft is arranged at an interval angle of 90 ° or less.