JPH0693407A - Bearing device and drainage pump and hydraulic turbine with the same and manufacture of bearing device - Google Patents

Abstract

PURPOSE:To manufacture a bearing part excellent in wear resistance and assembling properties by thermal-spraying a thermally sprayed film consisting essentially of WC or Cr3, C2, thereafter heating it in specified conditions and forming pores with specified density on the surface of the thermally sprayed film. CONSTITUTION:The sliding face of a bearing or a sleeve is coated with the thermally sprayed film consisting essentially of WC and contg. a binder of Ni, Cr and Co. Or, it is applied with the thermally sprayed film consisting essentially of Cr3 C2 and contg. a binder of NiCr. The applied thermally sprayed film is heated at about 300 to 550 deg.C for about >=1hr to regulate its coating hardness to >=1000 in Vickers hardness. Furthermore, the density of pores having >=20mum dimension formed on the surface of the thermally sprayed film is regulated to <=15/mm<2>. Thus, ductility is imparted to the coating, its resistance to impact is increased and the fracture and peeling of the film are reduced. As for a drainage pump using this bearing device, operation in a lubricant free state is permitted even if it is used as the one for advance standby operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drainage pump and a water turbine, and in particular, it has excellent wear resistance, high reliability and assemblability suitable for a pump and a water turbine that operate without supplying clean water to a bearing portion. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing device, a drainage pump using the bearing device, a water turbine, and a method for manufacturing a bearing portion thereof.

[0002]

2. Description of the Related Art With the rapid urbanization in recent years, most of the rainfall water flows into drains, so that the drainage cannot keep up and the number of urban floods overflowing the road tends to increase. To cope with this, a drainage pump station equipped with a drainage pump system is provided, but there is a problem that the operation and maintenance cost increases with the increase of the drainage pump station, and a drainage pump system by automatic operation is being considered. The problems of this drainage pump system are high performance and high reliability, and currently, as a technology corresponding to these, a non-water supply operation technology, a large capacity, and a preceding standby operation of the pump are being studied.

The non-water-supply operation technique refers to operation without supplying clean water between the bearing and the sleeve. Since there is no clean water supply device, there is no malfunction due to failure of the clean water supply device, clean water service sensor, etc. In order to enable waterless operation technology, it is necessary to have a bearing device that does not wear even when soil and sand contained in wastewater enters.

A conventional bearing device for a waterless pump is provided with a tungsten carbide (hereinafter, referred to as "high wear resistance and corrosion resistance").
A combination of a sleeve (called WC) (sintered body) and a ceramic bearing (sintered body) has been used. Regarding the combination structure of the sleeve made of WC and the bearing made of ceramics, JP-A-60-81517 and JP-A-60-88215.
It is disclosed in the publication.

On the other hand, increasing the capacity of the pump inevitably requires increasing the diameter of the bearing. However, if the conventional bearing device is a combination of a WC sleeve and a ceramic bearing, a large-diameter sintered sleeve and a sintered bearing are required. However, the sintering technology is not sufficient,
Further, there is a problem that the weight of the parts becomes large and the assembling work becomes difficult. Therefore, a hard film coating technique for covering a film having hardness equivalent to that of ceramics has been widely studied. As an example of using a sprayed film as a hard film, a non-feed water drainage pump using a combination of a sleeve coated with a WC sprayed film and a ceramic bearing is disclosed in "Tribologist", Vol. 36, No. 144, page 144. From 14
It is specified on page 7.

[0006] The bearings for water turbines are required to have wear resistance against sediment water as well as the bearings for drainage pumps. In consideration of this point, conventional turbine bearings have a silicon carbide (hereinafter referred to as SiC
Ceramics) have been used.

In many cases, a sprayed coating is used as a hard coating on the drain pump bearing portion. However, since the sprayed film is inferior in hardness and strength to the sintered body having the same composition, a method for increasing the hardness and strength of the sprayed film has been studied. For example, 50
A technique for enhancing the adhesive strength and strength of the sprayed coating by holding a plasma sprayed coating made of% Cr-50% Ni for about 1 to 100 hours at a temperature of about 700 ° C. to 800 ° C. after thermal spraying is disclosed.
No. 7-2872. Also, nickel-
A sprayed film of 20-80% NiCr containing phosphorus (NiP) as a main component is formed on the Fe-based material, and the temperature is 600 ° C-1000 ° C.
Japanese Patent Application Laid-Open No. 60-149762 discloses a method of increasing the strength of a sprayed film by performing heat treatment at a temperature of ° C.

In the case of bearings for water turbines, the bore diameter is large, and at present, split ceramics are arranged, and like the drainage pump bearings, a hard coating structure is desired. A bearing device for a water turbine using a WC sprayed film and a chromium carbide (hereinafter referred to as Cr ₃ C ₂ ) sprayed film is “Tarbo Machine”, 80th of the 26th lecture summary (May 1991). Pp. 85-85.

The preparatory standby operation is an idle operation at a water level lower than the drainable water level before the start of drainage. When the drainable water level is reached, full-power operation is possible and a rapid increase in drainage can be responded to. it can. However, in order to perform the preceding standby operation, the bearing performs idling operation in which the sliding part does not contain drainage for a short time, so the coefficient of friction between the bearing and sleeve is extremely low, and it is required that it will not be damaged by dry sliding. To be

A preceding standby operation for performing a long idle operation,
Bearings that are compatible with waterless operation have not yet been developed,
A method of externally supplying water to the sliding portion of the bearing during idling operation has been studied and is disclosed in JP-A-55-90718.

[0011]

The wear resistance of the bearing is indispensable for draining water containing earth and sand. In the case of a waterless bearing, the wear resistance to slurry is particularly important because no clean water is supplied to protect the bearing and sleeve.
Most of the sediment particles contained in sediment water are feldspar and quartz, and the maximum hardness is Vickers hardness (hereinafter referred to as Hv).
It is about 1000 (quartz). Therefore, the hardness required for the bearing and the sleeve is Hv1000 or more.

WC, SiC, silicon nitride (hereinafter referred to as Si ₃ N ₄
The hardness of the sintered body is about 1400 for WC, about 2800 for SiC, and about 1600 for Si ₃ N _4.
Both have Hv of 1000 or more, which is sufficient in terms of hardness and is excellent in wear resistance. However, considering the sintering technology, assembling workability, and manufacturing cost, there is a limit to the size of the entire sleeve and bearing made of a sintered body of WC, SiC, or Si ₃ N ₄ . Therefore, the use of a hard coating instead of the sintered body as described above is being studied. Considering the amount of wear, the film thickness is required to be several 100 μm or more,
The hard film manufacturing method is limited. As the hard coating for the drainage pump bearing, a film having a relatively high film thickness and a high hardness, which is mainly composed of WC and Cr ₃ C ₂ , is 100 to 200 μm.
The degree of thermal spray coating is widely used. However, the thermal sprayed film mainly composed of WC and Cr ₃ C ₂ formed by the thermal spraying method has a hardness lower than that of the sintered body, which is about Hv 600 to 1000, although it depends on the material, the forming method and the conditions.

The relationship between the hardness of various conventional sprayed coatings and the wear resistance to earth and sand water will be described with reference to FIG. FIG. 21 is the wear rate measured by the element test described in the examples. The various sprayed films used were various sprayed films formed on a stainless steel (hereinafter referred to as SUS) plate for the rotating side test piece, and α-SiC was used for the stationary side test piece. Other test conditions were a surface pressure of 2 kg / cm ² and a peripheral speed of 0.5 m /
The concentration of silica sand contained in the earth and sand water is 9 wt%. still,
The details of the test piece shape and sliding method are the same as the test conditions shown in FIG.

The abscissa of FIG. 21 is the Vickers hardness in cross section of the sprayed film, and the ordinate is the relative wear rate standardized with the wear rate of the WC-12% Co sintered body as a reference. The thermal sprayed film 1, the thermal sprayed film 2, and the thermal sprayed film 3 are conventional thermal sprayed films containing WC or Cr ₃ C ₂ as a main component, which are produced by a high speed flame spraying method and an explosive spraying method. As shown in FIG. 21, the abrasion resistance to earth and sand water strongly depends on the hardness of the sprayed coating, and as described above, the Vickers hardness of 1000 or more is good. Figure 21
From the results, it can be seen that the current sprayed coating cannot provide sufficient hardness and abrasion resistance against sediment water.

Generally, thermal spraying does not mean that only hard particles such as WC particles and Cr ₃ C ₂ particles are heated and sprayed, but metal particles such as Ni, Cr and Co are mixed and heated at the same time as a binder and sprayed. , Due to the dissolved metal particles W
C particles and Cr ₃ C ₂ particles are connected to form a coating film. The hardness of the sprayed film is lower than that of the sintered body, not that the hardness of the WC particles and Cr ₃ C ₂ particles in the sprayed film is low,
This is because the binder that connects the C particles and Cr ₃ C ₂ particles has defects such as voids, or the binding force between the binder and the WC particles and Cr ₃ C ₂ particles is insufficient.

Various improvements have been made to the thermal spraying method in order to increase the bonding force between the WC particles and the Cr ₃ C ₂ particles. For example, high-speed flame spraying that uses the combustion energy of flammable gas, which increases the speed of sprayed particles, and explosive spraying that uses the explosion of flammable gas have been developed. It is possible to increase the speed and form a sprayed film having higher hardness. However, it is clear from the element test shown in FIG. 18 that even the sprayed coatings obtained by each of these spraying methods do not have sufficient wear resistance to earth and sand water and their hardness is low.

In the ceramic bearings disclosed in the above-mentioned prior arts, Japanese Patent Laid-Open Nos. 60-81517 and 60-88215, it is difficult to sinter due to the large diameter of the bearing and the sleeve. No consideration has been given to the decrease in reliability and the decrease in assembly due to the increase in weight.

A waterless drainage pump ("Tribologist", Vol. 36, No. 2) using a combination of the above-mentioned conventional technique, a WC sprayed coating and a ceramic bearing (sintered body), and a WC sprayed coating and Cr ₃ Regarding the bearing structure for a water turbine using a C ₂ sprayed coating (“Tarbo Machine”, summary of the 26th lecture meeting), the hardness and resistance of the sprayed coating mainly composed of WC or Cr ₃ C ₂ No consideration was given to wear resistance and reliability.

In the above-mentioned prior art, Japanese Patent Application Laid-Open No. 57-2872 and Japanese Patent Application Laid-Open No. 60-149762, in the method for modifying a sprayed coating, the main base material Fe-based material and the thermal expansion coefficient In the case of a sprayed coating containing WC or Cr ₃ C ₂ as a main component, which is limited to a material close to the material or a material which is not deteriorated by heating and has a high hardness, the difference in thermal expansion becomes large because the heating temperature is high. As a result, the coating film breaks and it is difficult to use as it is. Furthermore, for equipment used underwater such as pumps,
The main material is limited to SUS. Therefore, when the modification of the thermal spray coating by heating shown in the above-mentioned prior art is applied, the heating temperature becomes higher than the annealing temperature of SUS of the base or the sensitization temperature for intergranular corrosion, and the hardness and corrosion resistance of the base are lowered. However, there is a problem that reliability is lowered as a result.

That is, in the above-mentioned prior art, no study has been made on the modification of the thermal spray coating containing WC, which has a large thermal expansion coefficient difference from that of the Fe-based material. Furthermore, no consideration is given to changes in hardness and corrosion resistance of the base material.

In the method of supplying water to the bearing sliding portion from the outside, which is disclosed in the above-mentioned prior art, 55-90718, the drainage station is stopped due to a malfunction of the external water supply device, and the drainage is stopped in an emergency. Possibly, there was a problem with reliability.

The present invention has been made in view of the above prior art and is applicable to a drainage pump system and a water turbine.
An object of the present invention is to provide a highly reliable bearing device having excellent wear resistance and assemblability, a drainage pump using the bearing device, a water turbine, and a method for manufacturing the bearing device.

[0023]

SUMMARY OF THE INVENTION In order to improve the wear resistance of the thermal spray coating coated on the sliding surface of the bearing device, which is the subject of the present invention, the thermal spray coating containing WC or Cr ₃ C ₂ as a main component is provided. After the thermal spraying of, the adhesive force of the thermal sprayed film does not decrease due to thermal stress,
This can be achieved by heating under a temperature condition in which the sprayed film does not deteriorate, the hardness of the underlying SUS does not extremely decrease, and the sensitization to intergranular corrosion does not occur.

The bearing device of the present invention has the following thermal spraying on the sliding surface of either or both of the bearing and the sleeve used in the bearing device provided with the bearing and the sleeve that slides with the bearing. It covers the membrane. The sprayed coating is W
A coating containing C as a main component and one or more of Ni, Cr or Co as a binder, or a coating containing a thermal spray coating containing Cr ₃ C ₂ as a main component and Ni and Cr as binders, The density of pores having a size of 20 μm or more formed on the surface of the sprayed film is 15 / mm ² or less.

Further, the coated thermal spray coating is coated 30 times after coating.
It is heated at a temperature of 0 ° C. or higher and 550 ° C. or lower for 1 hour or longer, the coating hardness is improved to a Vickers hardness of 1000 or higher, and sufficient abrasion resistance against earth and sand water is exhibited.

The material of the bearing and the sleeve covering the sprayed film may be Fe-based metal, and preferably stainless steel.

When one of the bearing and the sleeve is coated with the above sprayed film, the other is S on the sliding surface.
It may be one in which iC or Si ₃ N ₄ is arranged, or one entirely made of SiC or Si ₃ N ₄ .

The sleeve or bearing may be divided into two or more pieces.

The drainage pump or the water turbine of the present invention includes the bearing device having any one of the above features.

Furthermore, the bearing member of the present invention is a sprayed film containing WC as a main component and one or more of Ni, Cr or CO as a binder in the sliding portion of a stainless steel bearing member processed into a predetermined shape. or Cr ₃ after forming a thermally sprayed film containing Ni and Cr to C ₂ to binder as a main component, prepared by heating over 1 hour at a temperature of 300 ° C. or higher 550 ° C. or less, and then finishing operation to a predetermined size To do.

[0031]

It has been generally said that when a sprayed film containing WC and Cr ₃ C ₂ as a main component is heated, the strain which serves to increase the hardness of the coating disappears and the hardness decreases. Further, when a Fe-based material (SUS403 in the embodiment of the present invention) is used as a base material and a thermal sprayed film containing WC or Cr ₃ C ₂ having a small coefficient of thermal expansion as a main component is coated thereon, the difference in thermal expansion coefficient between the two is For this reason, it has been considered that when the film is heated after the film formation, the coating adhesive force is reduced due to thermal stress, and further, the WC particles or Cr ₃ C ₂ particles are oxidized due to the heating to deteriorate the properties of the sprayed film. Therefore, WC or Cr
It has not been considered desirable to heat the sprayed coating based on ₃ C ₂ after spraying. However, if the heating conditions are selected, the hardness can be increased without adversely affecting the sprayed film. For example, at a temperature of 300 ° C or higher and 550 ° C or lower, 1
By heating for more than a period of time, the hardness of the sprayed coating increases and it shows sufficient wear resistance against sediment water. The details of the mechanism and the examination result will be described in Examples.

The presence of pores in the sprayed coating reduces the strength of the sprayed coating itself, and also reduces the binding force between the WC particles or Cr ₃ C ₂ particles, so that the WC particles or Cr ₃ particles may slide during sliding.
The C ₂ particles fall off, which causes a decrease in wear resistance.
However, if the film is heated at a high temperature after the film is formed in order to eliminate the pores, the binder particles, the WC particles or the Cr ₃ particles as described above.
Oxidation of the C ₂ particles, decrease in the adhesive force of the sprayed film, and decrease in the hardness and corrosion resistance of the lower material, resulting in a decrease in reliability. However, according to the invention, WC or Cr
₃ C ₂ Even if the temperature and heating time are appropriately selected such that oxidation of the sprayed film, deterioration of film adhesion due to thermal stress, and hardness and corrosion resistance of lower materials do not occur, voids in the sprayed film It became clear that the hardness of the thermal sprayed film increased as the pore size decreased and the size of the pores decreased.

In particular, it has been found that when heated under the conditions of the present invention, large voids of 20 μm or more exceeding the maximum particle size of the binder particles, WC particles or Cr ₃ C ₂ particles are reduced.
Large pores of 20 μm or more are a direct cause of the dropout of WC particles or Cr ₃ C ₂ particles. Therefore 20μ
The reduction of large pores of m or more acts to improve the strength of the sprayed coating. Further, when the large pores of 20 μm or more are reduced, the ductility is imparted to the coating, the resistance to impact increases, the destruction and peeling of the coating decrease, and the reliability of the coating increases.

Further, since the pores become the corrosion generation points of the sprayed coating, the reduction of the pores makes the WC particles denser, the corrosion generated between the particles is suppressed, and the corrosion resistance to drainage is increased.

Further, even if the drainage pump of the present invention is used for the preceding standby operation, the bearing device which can be operated in the non-lubricated state is used, so that there is sufficient reliability.

Further, by forming the sleeve or the bearing into a divided structure, the manufacture becomes easy, and the effect is great especially for a large diameter one.

[0037]

Embodiments of the present invention will be described with reference to FIGS.

FIG. 1 is a vertical sectional view showing the structure of a drainage pump according to an embodiment of the present invention. Usually, the drain pump is provided with bearings at two locations, near the impeller and at the top.
The bearing device of this embodiment can be applied to both bearings. In FIG. 1, 1 is a main shaft, 2 is a sleeve attached to the main shaft, and 3 is a bearing. In this embodiment, the main shaft 1, sleeve 2 and bearing 3 are all made of SUS4.
03 was used.

Further, a pipe is installed at the drainage suction port of the casing of this pump, one end of which is supported by the rib of the casing, the other end of which is supported by the floor of the drainage pumping station and is open to the atmosphere.

In this pump, when the drainage water level is low, a pressure difference occurs between the pump internal pressure and the atmosphere, and the air is absorbed into the drainage from the pipe. As a result, the amount of flowing water is reduced, and the generation of vortices on the drainage surface causes an exciting force and contributes to pump vibration, which must be prevented. By sucking air from the pipe, it is possible to prevent the vortex from being generated even at a low water level where the vortex is likely to occur, so that stable drainage is possible.

Further, when the water level becomes sufficiently high, the pressure difference between the inside and outside of the casing decreases, and the intake from the pipe naturally stops.
Since the pressure change in the casing due to the drainage water level is used, it does not require external control and is highly reliable.

Further, by providing a valve at the open end on the atmosphere side, it is possible to control the intake amount and cancel this function.

The bearing device of this embodiment will be described with reference to FIGS. 2 is an enlarged view showing the bearing device installed on the upper portion of the drainage pump shown in FIG. 1, and FIG. 3 is a sectional view further enlarging the sliding portion of FIG. The method of manufacturing the sleeve and the bearing is S
After forming the sleeve base material 8 and the bearing base material 10 by machining in US403, quenching and tempering heat treatment are performed to increase the hardness of SUS403. The tempering temperature was set to about 700 ° C. so that SUS403 did not cause temper embrittlement during the subsequent modification of the sprayed coating. Bearing 3 after heat treatment
And Ni as a main component of WC on the sliding portion of the sleeve base material 8.
The thermal spray coatings 11 and 9 using Cr as a binder were coated by high speed flame spraying. After forming the sprayed film, a heat treatment of heating at 400 ° C. for 20 hours and holding was performed to increase the hardness of the sprayed film. After the heat treatment, the sleeve and the bearing were processed to have predetermined inner diameter and outer diameter and surface roughness. The sleeve 2 was fixed to the main shaft 1 with a detent 4.

The bearing 3 is attached to the bearing back metal 6,
It was fixed with a fixing member 7 via a bearing cushioning material 5. Further, the bearing 3 has an intrusion prevention member 1 for preventing intrusion of earth and sand into the sliding portion.
2 attached.

According to this embodiment, S is used as the sleeve base material.
Since US403 is used, the coefficient of thermal expansion matches that of the main shaft material to prevent generation of thermal stress, and since the toughness is high, a sleeve capable of stably holding the sprayed coating coated on the surface can be provided.

Further, since the hardness of the WC sprayed film is increased by heat treatment, the wear resistance is increased and the life and reliability of the bearing device are increased.

In this embodiment, the sprayed film formed on the sleeve and the bearing has been described as a sprayed film having WC as a main component and NiCr as a binder, but WC as a main component and Co as a binder. The same effect was obtained by using a thermal sprayed coating containing the above or a thermal sprayed coating containing Cr ₃ C ₂ as a main component and NiCr as a binder.

In the drainage pump of this embodiment, the bearing device exhibits stable sliding performance even under a non-lubricated condition, that is, in a non-water-supply state, and it is possible to perform better sliding after the water supply. it can.

Although the drainage pump of this embodiment is provided with the intrusion prevention member for preventing the infiltration of the sand into the sliding portion of the bearing device, even if the soil mixed in the drainage enters the sliding portion, Stable operation is possible because the sliding part has sufficient wear resistance.

Further, since good sliding performance can be obtained even in the non-lubricated state, highly reliable operation can be performed even in the use condition where the non-lubricated and lubricated states are repeated, that is, in the preceding standby operation.

FIG. 4 is a vertical sectional view of a bearing device for a pump showing another embodiment of the present invention. The sliding surface of the sleeve substrate 8 of SUS403 was coated with a sprayed film 9 containing WC as a main component and Co as a binder. Also, the bearing 1 that slides with the sleeve 2
3 was SiC. Sleeve 2 is 400 after the sprayed film is formed.
Heat treatment was performed at 20 ° C. for 20 hours to increase the hardness of the sprayed film.
The other structure is the same as that of the embodiment described in FIGS.

According to this embodiment, since the material of the bearing portion is a homogeneous and high-hardness sintered ceramic, the life of the bearing device is
Increased reliability.

In this embodiment, the sprayed film formed on the sleeve has WC as the main component and NiCr as the binder, but the main component is WC and Co.
Sprayed film with Cr as the binder or Cr ₃ C ₂ as the main component and N
The same effect was obtained by using a sprayed coating using iCr as a binder.

FIG. 5 is a vertical sectional view of a bearing device for a pump showing another embodiment of the present invention. The present embodiment is a bearing structure that can cope with the idling operation in which the drainage water level does not reach the bearing height during the preceding standby operation. It should be noted that the detailed structure of the sleeve 2 is not shown in the figure because it shows the entire structure. W on the sliding surface of the sleeve 2 made of SUS403 material
Coating a sprayed film containing C as a main component and a NiCr binder,
After forming the sprayed film, heat treatment was performed at 400 ° C. for 20 hours to increase the hardness of the sprayed film. Also, a bearing 13 that slides with the sleeve 2
Was made of SiC, was attached to the back metal 6, and was fixed to the fixing member 7 ′ protruding from the casing via the bearing cushioning material 5. Furthermore, the baffle plate 1 is attached to the fixing member 7 '.
Fixed 7 Further, the rotary water tank 18 was fixed to the main shaft 1. Water is stored in the rotary water tank 18, and lubricating water is present in the bearing sliding portion even in idling operation in which the drainage water level does not reach the bearing height. In this structure, since earth and sand are likely to accumulate in the rotary water tank 18, the earth and sand may invade the sliding portion during operation, but the resistance of the sprayed film 11 on the sliding surface of the sleeve whose hardness has been increased by heat treatment has increased. Wearability is sufficient and there is no hindrance to operation.

FIGS. 6 and 7 are sectional views of a sleeve fixing state and a fixing portion of a pump bearing device according to another embodiment of the present invention. In this example, a sleeve divided into four in the circumferential direction was used. The four-divided sleeves 2a, 2b, 2c and 2d are made of SUS403, and after forming a sprayed film containing Cr ₃ C ₂ as a main component and NiCr as a binder on the sliding surface with the bearing, 4
The heat treatment was performed at 00 ° C. for 20 hours. The sleeve parts 2a, 2b, 2c and 2d are fixed to the main shaft 1 by bolts 14 at two axial positions. The other structure is the same as that of the embodiment described in FIGS.

The method of manufacturing and assembling the bearing portion will be described below. The sleeve parts 2a, 2b, 2c and 2d are made of SUS403, and the same heat treatment as in the above bearing manufacturing method is performed. After the heat treatment, a sprayed film WC containing WC as a main component and NiCr or Co as a binder is formed on the sliding surface of the sleeve by high-speed flame spraying. After forming the sprayed film, the sleeve is heated to 400 ° C. and kept for about 20 hours. After the heat treatment, it is fixed to the main shaft 1 and processed into a predetermined size. It should be noted that although bolts are sufficient for fixing to the main shaft 1, if an adhesive is used together, the reliability is further increased.

In this embodiment, since the sleeve has a divided structure, the work of forming the sprayed film is facilitated, and the weight of each divided sleeve is about 1/100 of that of the integrated type.
4, which makes the handling easier.

FIG. 8 is an external view including a partial cross section of a bearing of a pump bearing device according to another embodiment of the present invention. This embodiment has a structure in which sliding members 19 in which sliding portions of the bearing are divided are arranged and formed. The sliding member 19 is SUS40.
A base material 10 made of No. 3 is formed by high-speed flame spraying with a sprayed film 11 containing WC as a main component and NiCr or Co as a binder. After the sprayed film is formed, heat treatment is performed at 400 ° C. for 20 hours to perform spraying Increased the hardness of the film. Sliding member 19
Is attached to the back metal 6 via the cushioning material 5 and arranged in the bearing casing 20. The sliding member 19 is the fixing jig 2
Although it is attached to the bearing casing 20 by 1, the reliability is further increased by using an adhesive together.

In this embodiment, since the bearing sliding portion has the divided structure, the work of forming the sprayed coating is facilitated and the respective sliding members 19 are fixed through the cushioning material 5. , Effective in preventing uneven contact.

In the present invention, a sleeve made of a super hard material containing WC as a main component can be made of SUS in the present invention, and the weight can be greatly reduced. Further, unlike the super hard material, when the base material is SUS, screw holes can be drilled, and thus the handling becomes easy. In particular, when the diameter is large, the weight of the sleeve increases, and the present invention is effective. The effect of the present invention on the reduction of the weight of the sleeve is summarized in FIG. FIG. 9 is a diagram showing the correlation between the outer diameter of the sleeve (hereinafter referred to as D) and the weight of the sleeve (hereinafter referred to as W). Sleeve weight W
Since it changes depending on the outer diameter D of the sleeve, it is standardized as W / D ² . With the sleeve of the present invention, W / D ² is significantly reduced, and is 0.05 or less.

FIG. 10 shows a sectional view of a water turbine using the bearing device of the present invention as a bearing for a water turbine as another embodiment. Figure 1
In No. 0, 22 is a main shaft for a water turbine, 23 is a sleeve, and 24 is a main component of WC and NiCr is a binder.
SUS40 which was heat-treated after coating a sprayed film containing 7% by weight (hereinafter referred to as WC-27% NiCr sprayed film)
3 made sleeve, 25 is a thermal sprayed film containing 25% of heat-treated Cr ₃ C ₂ as a main component and NiCr as a binder (hereinafter, C
A bearing made of SUS403, which is coated with (r ₃ C ₂ -25% NiCr sprayed coating) and then heat-treated, is a liner 26. The coating of the spray coating on the sleeve and the bearing was performed using high-speed flame spraying. The heat-treated sprayed film has wear resistance equivalent to that of the sintered body, as shown in the element test results. Moreover, since it is easy to increase the diameter, it is effective in reducing the cost and weight of the water turbine.

In order to examine the wear resistance of the bearings used in the above examples, the change in hardness of the thermal spray coating due to the heat treatment was examined by an element test. The change in hardness of the sprayed coating due to heating is
The test was conducted in the range of 0 ° C to 600 ° C and the heating time of 1 to 30 hours. The hardness of the sprayed film was measured by a micro Vickers hardness meter and shown by Vickers hardness (hereinafter referred to as Hv). In order to avoid the influence of the base, hardness is measured on the cross section of the sprayed film,
The load was constant at 300 g.

FIG. 11 shows a part of the above measurement results,
The change in hardness when the -27% NiCr sprayed coating is heated at 400 ° C is shown. The horizontal axis represents the heating time, and the horizontal axis represents the hardness of the sprayed film. The sprayed film is formed by high-speed flame spraying, the film thickness is about 100 μm after surface polishing, and the base is SUS403. The film is quenched before spraying and tempered at about 700 ° C. In addition, since the measured values of hardness vary,
The measurement was carried out at 10 points, and the maximum and minimum values among the measured values were shown as a variation range by a line, and the average value was shown by a circle.

As shown in FIG. 11, the hardness of the sprayed coating increases with time, reaches the maximum hardness in 10 to 30 hours, and then becomes almost constant although there is variation. The highest average hardness is H
v1014 (maximum value Hv1065, minimum value Hv890)
Is. A sintered body containing WC as a main component measured under the same conditions and 12% by weight of Co as a binder (hereinafter referred to as WC-
12% Co sintered body) hardness, average value Hv131
7 (maximum value Hv1404, minimum value Hv1235) is not reached, but compared with the average value Hv727 (maximum value Hv869, minimum value Hv604) of the hardness before heat treatment, the average value is about 3
The increase is 4%, which is a significant improvement.

FIG. 12 is a part of the measurement results, and shows the change in hardness when the WC-27% NiCr sprayed film was heated at 500 ° C., as in FIG. 11. The sample forming method, the shape, and the hardness measuring method are all the same as those in FIG. 11. The hardness of the sprayed coating reaches almost the maximum hardness after heating for about 1.5 hours. The maximum value of the average hardness is Hv1115 (maximum value Hv1139, minimum value Hv1084). The average value is about 47% higher than the hardness before heat treatment, which is almost equal to that of the WC-12% Co sintered body.

FIG. 13 is also a part of the measurement results. When a sprayed film containing WC as a main component and 12 wt% of Co as a binder (hereinafter referred to as WC-12% Co sprayed film) was heated at 400 ° C. Shows the change in hardness. The WC-12% Co sprayed film was also formed by high-speed flame spraying similar to the samples of FIGS. 11 and 12, and the film thickness was about 100 μm after surface polishing.
The base is heat-treated SUS403. Sample shape,
The hardness measurement method is also the same as in FIGS.
In the case of the WC-12% Co sprayed coating, the hardness increases with time, reaches the maximum hardness in 10 to 20 hours, and slightly decreases in 25 hours. The maximum hardness is Hv946 (maximum value Hv1149, minimum value Hv792) on average. Hardness before heat treatment, average value Hv584 (maximum value Hv652, minimum value Hv652
v490), the average value is about 62% increase.
Also, even when heated at 500 ℃, WC-27% N
The hardness change was similar to that of the iCr sprayed film, and the maximum hardness was reached by heating for about 1 hour.

FIG. 14 is also a part of the measurement results, showing Cr ₃ C ₂
The hardness change when a -25% NiCr sprayed coating is heated at 400 ° C is shown. The Cr ₃ C ₂ -25% NiCr sprayed film was also formed by high-speed flame spraying similar to each sample used in the measurement of FIGS. 11, 12 and 13 described above, and the film thickness was about 1 after surface polishing.
00 μm, the base is heat-treated SUS403. The shape of the sample and the method for measuring the hardness are also shown in FIGS.
Same as 3. For Cr ₃ C ₂ -25% NiCr sprayed coating, the hardness gradually increases with time. The maximum value of the average hardness after heating for 25 hours is Hv958 (maximum value Hv
1043 and the minimum value Hv905). Hardness before heat treatment, average value Hv791 (maximum value Hv817, minimum value Hv
744), the average increase is about 21%.
It does not increase remarkably as much as -27% NiCr sprayed film and WC-12% Co sprayed film. Also, when heated at 500 ℃,
The hardness gradually increases with time as in the case of heating at 400 ° C., but the ratio is larger.

As described above, WC-27% NiCr sprayed film, WC
The hardness of the -12% Co sprayed film and the Cr ₃ C ₂ -25% NiCr sprayed film is remarkably improved by heating at 400 to 500 ° C, and the hardness is almost equal to the hardness of the sintered body of WC-12% Co. . It is considered that by heating at 400 ° C. to 500 ° C., the bonding force between the WC particles or Cr ₃ C ₂ particles in the sprayed coating and the binder was increased and became almost equal to the sintered body.

Heating temperature 200 ° C. to 600 ° C., heating time 1
The results of the examination in the range of up to 30 hours are summarized below. When the heating temperature is 300 ° C. or lower, the hardness of the sprayed coating increases, but the rate of increase is extremely small and industrially difficult to use. Therefore, the heat treatment temperature is 300 ° C. or higher, preferably 350 ° C. or higher. However, the F used for the pump
The e-based material has a thermal expansion coefficient of approximately 12 to 17 × 10 to ⁶ / ° C., and the WC or Cr ₃ C ₂ based thermal spray coating has a thermal expansion coefficient of approximately 5 to 5.
Since it is 7 × 10 to ⁶ / ° C., if the heating temperature is too high, thermal stress is generated due to the difference in the coefficient of thermal expansion between the sprayed film and the base, and the adhesive force of the film is reduced. Peeling occurs. Further, when heat treatment is performed in the atmosphere, oxidation of the sprayed film occurs and wear resistance is reduced. Therefore, WC or Cr
_{As long as a 3} C ₂ -based spray coating is used, the heat treatment temperature is 550 ° C.
Hereafter, it is preferably 500 ° C. or lower. The sprayed film is preferably heated in an inert gas or in vacuum to prevent oxidation.

In FIG. 15, W sprayed to a thickness of about 200 μm
A metallographic photograph of a C-27% NiCr sprayed film heated at 400 ° C., surface-polished to a thickness of about 100 μm, further heated, and polished again to a mirror-finished state is shown. The final film thickness is about 90 μm. (A) is a photograph of an untreated sprayed coating, (B) is a photograph of a sprayed coating that has been heated for 10 hours, and (C) is a photograph of a sprayed coating that has been heated for 20 hours. All magnifications are 100 times.

Since the observation is performed without etching, W
No difference between the C particles and the binder NiCr can be observed, and all are observed as a white base. The areas that are scattered and appear black are holes. Comparing (A), (B) and (C), the number of holes decreases and the size also decreases with the heat treatment time. The sample used for the test is a SUS403 plate (26 mm
Since it was cut from a sprayed film formed on a surface of (× 26 mm), the difference in the number of holes was not caused by the spraying conditions, but was decreased by the heat treatment.
Incidentally, WC-12% Co sprayed coating or Cr ₃ c ₂ -25% Ni
The same phenomenon was observed in the Cr sprayed film.

FIG. 16 shows the WC-27% NiCr sprayed film 4
The relationship between the heating time and the density of pores having a size of 20 μm or more observed on the surface when heated at 00 ° C. is shown. still,
The method of observing the holes on the surface is the same as the method shown in FIG. On the other hand, when the structure of the WC-27% NiCr sprayed film was observed with a scanning electron microscope, it was found that WC particles and NiCr
The average particle size of the binder particles is about 10 μm, and is 20 μm or less at the maximum. Therefore, if the number of pores is not more than a few μm, it has little effect on the falling of WC particles. But 20
If the thickness is more than μm, the WC particles may fall off, which is a direct cause of lowering the strength of the sprayed coating. Therefore, in the measurement of pores this time, only particles having a particle diameter of 20 μm or more were measured.
Hereafter, all the holes are referred to as holes having a diameter of 20 μm or more.

As shown in FIG. 16, when the heating temperature is 400 ° C., the number of voids sharply decreases after heating for 15 hours or more. This change in pore density matches the change in hardness shown in FIG. That is, it is considered that the change in hardness of the sprayed film due to heating is caused by the density of pores in the sprayed film.

The relationship between the pore density and the hardness was determined from the change in hardness and the change in pore density with heating time shown in FIGS. 12 and 16 and is shown in FIG. When the hole density is 30 holes / mm ² or less, the hardness starts to increase, and when the hole density is 15 holes / mm ² or less, the hardness becomes desirable for the pump bearing portion. Therefore, in the sprayed film to be arranged on the pump bearing portion, the density of pores having a size of 20 μm or more existing on the surface is 15 / mm ² or less, preferably 10 / mm ² or less. Incidentally, WC-12% Co sprayed coating, the similar phenomenon in the Cr ₃ C ₂ -25% NiCr sprayed coating was observed.

The following element tests were conducted to examine the wear resistance of bearings and sleeves using the heat-treated sprayed coating against earth and sand water. A part of the method and the result will be described with reference to FIGS. FIG. 18 shows the shape of the test piece and the sliding method. The rotating side test piece 15 shown in (A) and the fixed side test piece 16 shown in (B) are immersed in water containing silica sand, assuming earth and sand water, and the rotating side test piece is rotated as shown in (C). Then, a predetermined surface pressure is applied and sliding is performed. After sliding for a predetermined time, the wear amount of both samples was measured. The amount of wear was measured by measuring the thickness of the rotating test piece 15 before and after the test and by measuring the surface shape of the stationary test piece 16 before and after the test with a surface roughness meter. The condition range examined was a surface pressure of 1 to 10 kg / cm ² , a peripheral speed of about 0.5 to 5 m / s, and a silica sand concentration of 0.1 to 10 wt%.
Is. It should be noted that in order to reduce the effect of the silica sand itself being worn, the sand water is changed every 3.6 km of sliding, and the silica sand is changed between the two test pieces every time the sand water is changed so that the sand sand is easily caught between the two test pieces. And the sliding test was repeated.

FIG. 19 is a part of the results of examining the wear resistance of the heat-treated sprayed film by the above test. The horizontal axis represents the sliding distance, and the vertical axis represents the average amount of wear of the rotating test piece. Fixed side test piece is α-SiC, rotating side test piece is WC-27% Ni
It is a Cr sprayed film, has a film thickness of about 100 μm, and the base is SUS403 which has been subjected to quenching and tempering heat treatment. Regarding the heat treatment conditions for the sprayed film, refer to the results in FIG. 12 and 400 ° C. × 2
It was set to 0 hours. As comparative materials, a WC-12% Co sintered body and an untreated WC-27% NiCr sprayed film were tested as rotating side test pieces under the same conditions. Other test conditions are a surface pressure of 2 kg / cm ² , a peripheral speed of 0.5 m / s, and a silica sand concentration of 9 wt%.

In FIG. 19, the line (1) indicated by-▲-is the heat-treated WC-27% Ni which is the bearing member of the present invention.
Change in wear amount of Cr sprayed film, line (2) shown by-○-is a conventional bearing member which is a comparative material WC-12% Co
The wear amount change of the sintered body, and the line (3) indicated by -Δ- is the wear amount change of the unheated WC-27% NiCr sprayed coating which is the comparative material. The wear rate of the non-heat-treated WC-27% NiCr sprayed coating is about three times that of the WC-12% Co sintered body, while the heat-treated WC-27% NiCr sprayed coating is almost the same. Indicates the wear rate. That is, 400 ° C x 20
By the heat treatment for a long time, the wear amount of the WC-27% NiCr sprayed coating against the earth and sand water was reduced to about 1/3. This decrease in the amount of wear is considered to be due to the increase in hardness of the thermal spray coating shown in FIG. 12 due to the heat treatment. From the relationship between the hardness and the wear rate of the sprayed coating shown in FIG. 21, the wear resistance of the heat-treated sprayed coating is a reasonable value. Although not shown in FIG. 19, WC-27% heat-treated at 400 ° C. for 20 hours
The combination of NiCr sprayed coating and Si ₃ N ₄ also shows good wear resistance. Si ₃ N ₄ used for the fixed-side test piece showed excellent wear resistance over SiC.

According to the same test, the WC-12% Co sprayed film also exhibits the effect of improvement by the same heat treatment. However, in the case of WC-12% Co sprayed film, WC-27% NiCr
Since the hardness does not increase as much as the sprayed film, it does not reach the wear resistance of the WC-12% Co sintered body or the heat-treated WC-27% NiCr sprayed film. Further, Co, which is the binder, is inferior in corrosion resistance to NiCr, and therefore wear due to corrosion may occur. In the heat-treated WC-12% Co sprayed film under these conditions, the pore density on the surface is reduced, so that even the Co binder has improved wear resistance against corrosive wear. However, the corrosion resistance to salty wastewater such as seawater is still insufficient. Therefore, the bearing using the WC-12% Co sprayed film cannot be used depending on the use environment.

According to a similar test, Cr ₃ C ₂ -25% N
The iCr sprayed film also has improved wear resistance. However, WC-2
The wear resistance is not significantly improved as compared with the 7% NiCr sprayed coating and the WC-12% Co sprayed coating. This, Cr ₃ C ₂ -25% N
The hardness of the iCr sprayed film itself is essentially WC-27% NiC
This is because the effect is small even if the heat treatment is performed, because it is not as high as the r sprayed film and the WC-12% Co sprayed film.

The results shown in FIG. 19 and the case where the heat-treated WC-27% NiCr sprayed film was used for both the fixed-side and the rotation-side test pieces and the heat-treated WC-27% Ni for the rotation-side test piece.
Cr sprayed coating, the heat treatment on the fixed side test piece already Cr ₃ C ₂ -25
Along with the results obtained when the% NiCr sprayed coating was used, the respective wear rates are collectively shown in FIG.

FIG. 20 shows the wear rates of both the fixed-side and the rotating-side test pieces during the test time of 60 hours. The test conditions are the same as the test of FIG. The relative wear rate on the vertical axis is 1.0 based on the wear rate of each of the test pieces on the rotation side and the fixed side of (A) which is a combination of a WC-12% Co sintered body and α-SiC. And the wear rate of each sample is shown as a relative value. In the bar graph, the shaded side is the wear rate of the rotating side test piece, and the non-shaded side is the wear rate of the stationary side test piece.

The combination (A) is a combination of the WC-12% Co sintered body and α-SiC, and is the result of the curve (2) in FIG. (B) is a combination result of the unheated WC-27% NiCr sprayed film and the α-SiC shown in the curve (3) of FIG. 19. (C) is the heat-treated WC-27% N which is the bearing member of the present invention shown in the curve (1) of FIG.
It is a result of combination of iCr sprayed film and α-SiC.
(D) is a heat-treated WC-2 which is the bearing member of the present invention.
7% NiCr sprayed coating and heat treated WC-27% NiCr
As a result of combination with the sprayed film, (E) is a heat-treated WC-27.
% NiCr sprayed coating and heat-treated Cr ₃ C ₂ -25% NiC
This is the result of combination with the r sprayed film. The heat treatment conditions for the sprayed coating are all 400 ° C. × 20 hours.

As described with reference to FIG. 19, the combination (C) is the combination (A) for both the fixed side and the rotating side test pieces.
That is, it shows almost the same wear resistance as the combination of the WC-12% Co sintered body and α-SiC. Even in the combination of (D) in which the heat-treated WC-27% NiCr sprayed film was used for both the fixed side and rotating side test pieces, the rotating side and fixed side test pieces were almost the same as the WC-12% Co sintered body. Showed wear resistance.

Heat treatment WC-27% N of fixed side test piece
The iCr sprayed film showed excellent wear resistance equal to or higher than α-SiC. The hardness of α-SiC is an average value Hv2704 (maximum value Hv2874, minimum value Hv2591), which is much higher than that of the heat-treated WC-27% NiCr sprayed film. Nevertheless, the WC-27% NiCr sprayed coating is α-S
It is considered that the reason why the wear resistance is superior to that of iC is due to the ductility of the both, that is, the difference in fracture toughness. α-S
The fracture toughness of iC is about 3.9 (MN / m · √m),
About 13 (MN of WC-27% NiCr sprayed film after heat treatment)
/ M · √m). Heat treated WC-27% Ni
It is considered that the excellent fracture toughness of the Cr sprayed coating affected the wear resistance more than the hardness, and exhibited the above-mentioned excellent wear resistance. The fracture toughness is measured by the Vickers indentation method.

Heat treated WC-27% N on the rotating side test piece
iCr sprayed film, fixed side test piece heat treated Cr ₃ C ₂ -2
The combination (E) using the 5% NiCr sprayed coating showed a result that the relative wear rate of the rotating side test piece was almost the same as the combination (C) and (D). However, the wear rate of the heat-treated Cr ₃ C ₂ -25% NiCr sprayed film of the fixed side test piece was
The value was higher than that of α-SiC or the heat-treated WC-27% NiCr sprayed film. It is considered that this is because, as shown in FIG. 14, the hardness of the Cr ₃ C ₂ -25% NiCr sprayed film does not significantly increase even if the heat treatment is performed. However, under the condition that the temperature of the waste water is high, the Cr ₃ C ₂ -25% NiCr sprayed film showed wear resistance equal to or higher than that of the WC-27% NiCr sprayed film. This is Cr ₃ C ₂ -25% NiC
This is considered to be because the hardness of the r sprayed film did not decrease much at high temperatures. Therefore, depending on the usage environment, heat-treated WC-2
7% NiCr sprayed coating and heat-treated Cr ₃ C ₂ -25% Ni
The combination of Cr sprayed coatings becomes good.

The above results are summarized below.

When a heat-treated WC-27% NiCr sprayed coating is used for the sleeve and combined with a SiC or Si ₃ N ₄ bearing, good wear resistance and sliding characteristics are obtained. In this case, since SiC and Si ₃ N ₄ increase in strength when a compressive stress is applied, it is better to use SiC or Si ₃ N ₄ on the bearing side of the structure supported by the back metal by shrink fitting. Heat treated WC-27%
When NiCr sprayed film is used for both sleeve and bearing,
Shows excellent wear resistance and sliding properties. in this case,
Similarly, a WC sprayed coating using Co as a binder can also obtain excellent wear resistance, but when the waste water contains salt, it is difficult to use due to corrosion. When the heat-treated WC-27% NiCr sprayed film and the heat-treated Cr ₃ C ₂ -25% NiCr sprayed film are used for the sleeve and the bearing, the heat-treated WC-27% N
The wear resistance as good as that of the combination of the iCr sprayed coatings cannot be obtained. However, when the drainage temperature is high, it shows better characteristics. In this case, either WC-
A 27% NiCr sprayed coating may be provided and does not affect the characteristics.

Therefore, in the bearing structure of the present invention, the wear resistance of the sliding surface of the sleeve and the bearing is almost the same as that using the WC-12% Co sintered body for the bearing, and the weight of the parts of the sleeve and the bearing is large. Assembling is excellent because there are few Further, since the sleeve and the bearing have high toughness, there is no occurrence of damage due to impact, resulting in high reliability. Therefore, the rotating machine using the bearing structure of the present invention, such as a pump and a water turbine, has high reliability.

In each of the above embodiments, high speed flame spraying was used as the sprayed film forming method, but explosive spraying, reduced pressure plasma spraying, laser spraying, plasma spraying may be used, and the manufacturing method is not limited. . The hardness before heat treatment is preferably high, and high speed flame spraying and explosive spraying capable of forming a sprayed film of high hardness are desirable.

Although SUS403 is used as the material for the sleeve base material and the bearing base material in each of the above embodiments, any material that can be used in water may be used. Considering the coefficient of thermal expansion of the sprayed film containing WC or Cr ₃ C ₂ as a main component, SUS403 is more preferable than SUS304 having a large coefficient of thermal expansion. Also, considering the deterioration of corrosion resistance of SUS due to heat treatment, SUS304L or S containing less carbon
US316L is preferred.

In each of the above embodiments, NiC is used as the binder.
r and Co are used, and the content rates are 12 wt% and 25 wt
%, 27 wt%, but the content is not limited as long as the characteristics of the sprayed film are satisfied.

[0092]

According to the present invention, WC or Cr ₃ C ₂
By heating the sprayed film containing as a main component under predetermined conditions, the bonding force between the WC particles, Cr ₃ C ₂ particles and the binder is increased, and as a result, the pores of the sprayed film are reduced and the hardness is an average value. It is increased by about 50 to 60%, and the wear resistance to earth and sand water is improved to about three times that before the heat treatment. This characteristic is almost the same as the ceramic sintered body such as WC-12% Co.
o Instead of the sleeve and the bearing made of a sintered body, a sleeve and a bearing in which a metal surface is coated with a sprayed film can be used.

As a result, it is possible to manufacture a large-diameter bearing and sleeve which could not be manufactured with the sintered body of WC, SiC and Si ₃ N ₄ .

Further, the weight of the bearing and the sleeve is reduced regardless of the diameter, so that the assemblability is significantly improved.

Further, instead of the sintered body of WC, SiC, and Si ₃ N _{4 having} low toughness, stainless steel can be used as the base material, so that the reliability of the bearing and the sleeve is increased. Therefore, the reliability of pumps and turbines using this bearing device is increased.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a drainage pump structure according to an embodiment of the present invention.

FIG. 2 is a partial cross-sectional perspective view showing a bearing device according to an embodiment of the present invention.

FIG. 3 is a vertical sectional view of a bearing device according to another embodiment of the present invention.

FIG. 4 is a vertical sectional view of a bearing device according to another embodiment of the present invention.

FIG. 5 is a vertical sectional view of a bearing device according to another embodiment of the present invention.

FIG. 6 is a perspective view showing a sleeve structure according to another embodiment of the present invention.

7 is a cross-sectional view taken along the line AA of FIG.

FIG. 8 is a partial cross-sectional perspective view showing a bearing according to another embodiment of the present invention.

FIG. 9 is a relationship diagram showing the correlation between the outer diameter D and the weight W / (outer diameter D) ² of the sleeve of another embodiment of the present invention.

FIG. 10 is a cross-sectional view showing a water turbine structure of another embodiment of the present invention.

FIG. 11 is a diagram showing a change in hardness of a WC-27% NiCr sprayed coating when heated at 400 ° C.

FIG. 12 is a view showing a change in hardness of a WC-27% NiCr sprayed coating when heated at 500 ° C.

FIG. 13 is a diagram showing a change in hardness of a WC-12% Co sprayed film when heated at 400 ° C.

FIG. 14: 400 ° C. of Cr ₃ C ₂ -25% NiCr sprayed film
It is a figure which shows the hardness change at the time of heating.

FIG. 15 is a metallographic photograph showing the state of change of the WC-27% NiCr sprayed coating when heated at 400 ° C.

FIG. 16 is a graph showing the relationship between the pore density of the WC-27% NiCr sprayed coating and the heating time when the sprayed coating is heated at 400 ° C.

FIG. 17 is a relationship diagram between the sprayed film surface pore density and the hardness when the WC-27% NiCr sprayed film is heated at 400 ° C.

FIG. 18 is a diagram showing a shape of a wear test piece and a sliding method.

FIG. 19 is a WC-12% Co sintered body by an abrasion test, an unheated WC-27% NiCr sprayed film and a heat-treated WC-.
It is a relationship diagram of a sliding distance and a wear amount of a 27% NiCr sprayed coating.

FIG. 20 is a comparative wear rate comparison diagram of various material combinations including a heat-treated WC-27% NiCr sprayed coating and a heat-treated Cr ₃ C ₂ -25% NiCr sprayed coating.

FIG. 21: Hardness of each conventional sprayed film and WC for sediment water
It is a figure which shows the relative wear rate on the basis of a -12% Co sintered compact.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Main shaft, 2 ... Sleeve, 3 ... Bearing, 4 ... Sleeve stopper, 5 ... Bearing cushioning material, 6 ... Bearing back metal,
7, 7 '... Fixing member, 8 ... Sleeve base material, 9, 11 ... Thermal spray film, 10 ... Bearing base material, 13 ... Ceramic bearing, 14
... Split sleeve fixing bolts, 15, 16 ... Wear test pieces,
17 ... Baffle plate, 18 ... Rotating water tank, 19 ... Sliding member, 20 ... Bearing casing, 21 ... Fixing jig, 22 ...
Turbine spindle 23, sleeve stopper, 26 liner.

Front page continuation (72) Kenji Otani, Kenjicho, Tsuchiura, Ibaraki Prefecture, 603, Tsuchiura Plant, Hiritsu Manufacturing Co., Ltd. (72) Koji Aizawa, 502, Jinmachi, Tsuchiura, Ibaraki, Institute of Mechanical Research, Ltd. (72) Inventor Mitsuaki Haneda, 502 Jinritsu-cho Machinery Research Center, Tsuchiura-shi, Ibaraki Machinery Research Laboratories, Ltd.

Claims (19)

[Claims] 1. A bearing device comprising a bearing and a sleeve that slides on the bearing. At least one of the bearing and the sleeve has a sliding surface whose main component is WC and is a binder. Is made of a metal coated with a sprayed film containing any one or more of Ni, Cr or Co, and the density of pores having a size of 20 μm or more formed on the surface of the sprayed film is 15 / mm ^2. The bearing device is characterized by the following. 2. A bearing device comprising a bearing and a sleeve that slides on the bearing, wherein either the bearing or the sleeve has a WC as a main component on its sliding surface as a binder. It is made of metal coated with a sprayed film containing one or more of Ni, Cr or Co, and the other is made of SiC or Si ₃ N ₄ , or has WC as a main component on the sliding surface and Ni as a binder. It consists of a sprayed film containing one or more of Cr or Co, a sprayed film containing Cr ₃ C ₂ as a main component and Ni and Cr as a binder, and a metal with either SiC or Si ₃ N ₄ arranged. The density of pores having a size of 20 μm or more formed on the surface of the sprayed film is 15 / mm ²
The bearing device is characterized by the following. 3. A bearing device comprising a bearing and a sleeve that slides on the bearing, wherein at least one of the bearing and the sleeve has a sliding surface whose main component is WC. Is made of a metal coated with a sprayed film containing any one or more of Ni, Cr or Co, and the sprayed film is heated at a temperature of 300 ° C. or more and 550 ° C. or less for 1 hour or more after coating, and the thermal spraying is performed. Vickers hardness of the film is 1000
The bearing device as described above. 4. A bearing device comprising a bearing and a sleeve that slides on the bearing, wherein the sliding surface of the sleeve has WC as a main component and Ni, Cr or Co as a binder. It is made of a metal coated with one or more sprayed coatings, and the ratio W / D ² of the weight W in kg unit to the outer shape D in cm unit is 0.05 or less. Bearing device. 5. The method according to any one of claims 1 to 4,
A bearing device, wherein the sprayed film thickness is 100 μm or more and 200 μm or less, and the sliding portion of the sleeve and / or the bearing is divided into two or more. 6. A casing comprising: a casing through which drainage flows; and a main shaft which is supported by a bearing device in the casing and has an impeller arranged in a part thereof to rotate. In a drainage pump in which at least one place is operated without supplying clean water from the outside, one or both of the bearings and the sleeves constituting the bearing device are coated with a sprayed film. The drainage pump is characterized in that the sprayed film has a density of pores having a size of 20 μm or more formed on its surface of 15 / mm ² or less. 7. A casing comprising a casing through which drainage flows, and a main shaft supported by a bearing device in the casing and having an impeller arranged in a part thereof to rotate. In a drainage pump in which at least one place is operated without supplying clean water from the outside, one or both of the bearings and the sleeves constituting the bearing device are coated with a sprayed film. The drainage pump, wherein the sprayed film is heated at a temperature of 300 ° C. or higher and 550 ° C. or lower for 1 hour or longer after being coated, and the Vickers hardness of the sprayed film is 1000 or higher. 8. A casing having a casing through which drainage flows, and a main shaft supported by a bearing device in the casing and having an impeller arranged in a part thereof to rotate, the bearing device comprising: In a drainage pump in which at least one place is operated without supplying clean water from the outside, a sliding surface of a sleeve constituting the bearing device is coated with a sprayed film, and its kg unit Weight W and cm
A drainage pump having a ratio of W / D ² of 0.05 or less with respect to the outer shape D of the unit. 9. A bearing comprising: a casing through which drainage flows; and a main shaft which is supported by a bearing device in the casing and has an impeller arranged in a part thereof to rotate. In a drainage pump in which at least one place is operated without supplying clean water from the outside, one or both of the bearings and the sleeves constituting the bearing device are coated with a sprayed film. The density of the pores having a size of 20 μm or more formed on the surface of the sprayed film is 15 / mm ² or less, and further, on the outer peripheral side of the main shaft, of the bearing and the bearing fixing member. A drainage pump, characterized in that a water storage tank having an open upper portion is fixed so as to surround the lower end surface and the outer peripheral side. 10. The spray coating according to claim 6, wherein the sprayed film contains WC as a main component and Ni or C as a binder.
Any one of r and Co containing one or more, or one containing Cr ₃ C ₂ as a main component and Ni and Cr in the binder, and having a film thickness of 100 μm or more, 20
A drainage pump having a diameter of 0 μm or less, wherein the sliding portion of the sleeve and / or the bearing is divided into two or more. 11. A bearing having a casing in which a fluid flows, and a main shaft supported by a bearing device in the casing and having a runner arranged in a part thereof to rotate, the bearing device comprising: In at least one of the water turbines that is operated by supplying the fluid, at least one of the bearing and the sleeve constituting the bearing device or both sliding surfaces are coated with a sprayed film. A water turbine, wherein the sprayed film has a density of pores having a size of 20 μm or more formed on its surface of 15 holes / mm ² or less. 12. A bearing comprising: a casing in which a fluid flows; and a main shaft supported by a bearing device in the casing and having a runner arranged in a part thereof to rotate. In at least one of the water turbines that is operated by supplying the fluid, at least one of the bearing and the sleeve constituting the bearing device or both sliding surfaces are coated with a sprayed film. The water spray turbine is characterized in that the sprayed film is heated at a temperature of 300 ° C. or higher and 550 ° C. or lower for 1 hour or longer after being coated, and the Vickers hardness of the sprayed film is 1000 or higher. 13. A casing comprising a casing in which a fluid flows, and a main shaft supported by a bearing device in the casing and having a runner arranged in a part thereof to rotate, the bearing device comprising: The sliding surface of the constituent sleeves is coated with a sprayed film, and the ratio W / D ² of the weight W in kg unit to the outer shape D in cm unit is 0.05 or less. Water turbine. 14. The spray coating according to claim 11, wherein the sprayed film contains WC as a main component and Ni as a binder.
A water turbine which is either one containing one or more of Cr or Co or one containing Cr ₃ C ₂ as a main component and Ni and Cr in a binder. 15. After coating the sliding portion of the metal bearing member with a sprayed coating containing WC as a main component and one or more of Ni, Cr and CO on a binder, 300 ° C. or higher 55
A method of manufacturing a bearing member, which comprises heating at a temperature of 0 ° C. or lower for 1 hour or more, and then finishing working to a predetermined size. 16. A sliding portion of a metal bearing member is coated with a sprayed film containing Cr ₃ C ₂ as a main component and Ni and Cr as a binder, and then heated at a temperature of 300 ° C. or higher and 550 ° C. or lower for 1 hour or longer. Then, the method for producing a bearing member is characterized by finishing the product into a predetermined size. 17. A sliding member having a surface coated with a sprayed film, characterized in that the density of holes having a size of 20 μm or more formed on the surface of the sprayed film is 15 holes / mm ² or less. Sliding member. 18. The thermal spray coating according to claim 17, wherein the WC is a main component and the binder contains one or more of Ni, Cr and Co, and the Cr ₃ C ₂ main component is a binder. A sliding member comprising one of Ni and Cr. 19. A pump for performing a preceding standby operation provided for draining water discharged during rainfall, comprising a bearing device that is in a non-lubricated state during a standby operation and is lubricated by drainage during a drain operation. The bearing device is a bearing,
The bearing casing and the sleeve are provided, and the sleeve has WC as a main component on the surface of stainless steel and NI and Cr as the binder.
Alternatively, the drainage pump is characterized in that a thermal spray coating containing at least one or a plurality of Co is applied, and the bearing is configured by combining divided ceramic pieces.