JPH11210611A - Underwater bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve reliability and safety as well as improving abrasion resistance by branching and leading out a water feeding pipe having an opening/ closing valve from an upstream side from an inlet valve of a hydraulic iron pipe, and supply water in the hydraulic iron pipe to a bearing part through the water feeding pipe. SOLUTION: A power generator 15 is directly connected to an upper part of a hydraulic turbine 13 through a coupling 14, and a hydraulic iron pipe 16 is connected to a casing 8. An inlet valve 17 is arranged in the hydraulic iron pipe 16, and a water feeding pipe 18 is branched and led out from the hydraulic iron pipe 16 to an upstream side from the inlet valve 17. The tip end of the water feeding pipe is opened to a lower part of a submerged bearing, and an opening/closing valve 19 is provided on the way of the water feeding pipe 18. The opening/closing valve 19 is opened, and thereby, water in the hydraulic iron pipe 16 is automatically supplied to a bearing, and the bearing is lubricated. Since the hydraulic pipe 18 is branched and led out at the upstream side of the inlet valve 17, lubricating water is surely supplied to the bearing when a hydraulic turbine is stopped, namely, when the inlet valve 17 is closed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an underwater bearing device for performing water lubrication in a hydraulic machine such as a water turbine or a pump turbine.

[0002]

2. Description of the Related Art FIG. 16 is a view showing an underwater bearing device of a general water turbine or a pump water turbine. A rotating shaft 2 having a lower end directly connected to a runner 1 is rotatably supported by a bearing 3. ing. The bearing 3 is disposed in a bearing housing 5 mounted on an upper cover 4, and the bearing housing 5 seals water between the outer periphery of the rotating shaft 2 above and below the bearing 3. Apparatuses 6a and 6b are provided, and a water tank 7 is provided above the bearing housing 5. The flow rate and flow direction of the fluid flowing from the casing 8 into the stay vanes 9 are adjusted by the guide vanes 11 provided between the upper cover 4 and the lower cover 10, and flow into the runner chamber 12. The generator is rotated, and the generator is rotated via a rotating shaft 2 to which the runner 1 is directly connected, to generate power.

In general, in a submerged bearing device, a rotary shaft 2 is supported by a bearing 3 disposed in a bearing housing 5 using water as a lubricant. That is,
Water is supplied between the rotating shaft 2 and the bearing 3 by a lubricant supply unit. However, since water has a lower viscosity than oil, the load capacity of the bearing 3 (the weight of the rotating shaft that can be supported by the pressure of the lubricant in the bearing) is reduced, and when the rotating shaft 2 is started or stopped, In a so-called transient state when an external force is applied to the bearing 2, the rotating shaft 2 and the bearing 3 are likely to come into contact with each other, and the sliding surface of the bearing 3 may be damaged.

For this reason, a material that can withstand contact with the rotating shaft 2 is used for the bearing 3. That is, while using a metal material such as white metal for the bearing, providing a lubricating oil supply means for supplying grease or lubricating oil, or using a soft synthetic resin such as a phenol resin for the bearing 3,
Further, a lubricating water supply means for supplying fresh water as a lubricant is provided.

[0005]

However, in a bearing device using grease or lubricating oil, there is a possibility that the grease or lubricating oil flows out of the bearing device. There's a problem. In addition, in the case where soft synthetic resin such as phenol resin is used for the bearing and fresh water is supplied as a lubricant, water containing a slurry or the like is particularly used as the lubricant because the wear resistance of the bearing is low. In such a case, there is a problem in reliability and safety due to wear of the bearing member. As a bearing device that solves this problem, a hard rubber bearing developed especially as a marine bearing has been proposed. This bearing responds to foreign substances such as slurry by deformation of rubber. However, for this bearing,
The lubricant must be continuously supplied for the purpose of eliminating foreign substances. If the supply of the lubricant is insufficient, seizure and burning may occur. Furthermore, these bearings are limited in surface pressure (load per unit area), and it is difficult to support a high-load rotating shaft. Also. In order to reduce the surface pressure, it is necessary to set the length of the bearing surface larger than the diameter of the bearing, for example, there are structural restrictions, and the degree of freedom in design is limited.

In view of the above, the present invention can always supply lubricating water to the bearing portion as required, and can improve the wear resistance and improve the reliability and safety. It is intended to obtain an underwater bearing device.

[0007]

According to a first aspect of the present invention, a water supply pipe having an on-off valve is branched and led out from an upstream side of an inlet valve of a penstock for supplying water to a runner chamber of a hydraulic machine. The water in the penstock is supplied to the bearing portion via the. Since lubrication water is taken directly from the penstock upstream of the inlet valve, lubricating water can always be supplied to the sliding part of the bearing even when the turbine is stopped, eliminating the need for water supply equipment. can do.

According to a second aspect of the present invention, in the first aspect, a second water supply pipe having an on-off valve is branched and led out from an upstream side of an inlet valve of the penstock, and is passed through the second water supply pipe. The water in the penstock is supplied to a space between the outside of the shaft sealing device and the inside of the upper cover.

In this case, it is possible to prevent the lubricating water from flowing out of the bearing due to a temporary negative pressure on the runner side during the operation of stopping the operation of the water turbine or the like.

According to a third aspect of the present invention, in the first and second aspects, the on-off valve is an electrically operated valve, and the electrically operated valve is an electromagnetically operated valve.
Depending on the sequence at the start and stop of the water turbine operation,
The electric operation or the opening and closing operation of the electromagnetic operation valve is performed. In this way, by incorporating the opening / closing operation of the electric operation valve or the electromagnetic operation valve into the sequence at the time of starting and stopping the operation of the turbine, several minutes to several tens of minutes before the rotation of the rotating shaft, and the rotating shaft stops. Even for several minutes to several tens of minutes, lubricating water can be reliably supplied to the bearing sliding portion.

A fourth aspect of the present invention is characterized in that the electrically operated valve or the electromagnetically operated valve is opened and closed by a flow signal from a flow meter provided in the water supply pipe or the second water supply pipe. Thus, the electrically operated valve or the like is opened and closed in accordance with the flow rate, the flow rate is controlled so as to always reach the set flow rate value, and it can be confirmed whether lubricating water is flowing.

Further, in the fifth invention, the electrically operated valve or the electromagnetically operated valve is controlled by a detection signal from a pressure sensor provided in a space between the outside of the shaft sealing device holding plate and the inside of the upper cover. It is characterized in that opening and closing are controlled.

That is, when the operation of stopping the operation of the water turbine or the like is stopped, the runner side temporarily becomes negative pressure, and accordingly, the space outside the shaft sealing device holding plate and inside the upper cover also becomes negative pressure. By detecting the negative pressure with a pressure sensor and opening and closing an electric operation valve or the like, lubricating water can be stably supplied to the bearing sliding portion.

A sixth aspect of the present invention is characterized in that the water supply pipe branched from the penstock and the second water supply pipe are provided with a water intake cover for guiding water in the penstock to the water supply pipe side. I do. Thus, in this case, the water inlet cover can reliably maintain the amount of water to the water supply pipe and the second water supply pipe during rotation of the main engine.

According to a seventh aspect of the present invention, the water supply pipe branched from the penstock and the second water supply pipe are provided with a slurry separator for separating large foreign matters contained in water. . In this case, equipment such as a rapid filtration device can be omitted.

According to an eighth aspect of the present invention, the outer peripheral surface of the rotating shaft facing the bearing is coated with a cemented carbide material or ceramics, and the bearing surface of the bearing is coated with a cemented carbide material or ceramics. It is characterized by bearings. Further, a ninth aspect of the present invention is characterized in that an electric operation valve or an electromagnetic operation valve provided in a water supply pipe is opened and closed by a water level sensor provided in a bearing housing above the bearing. Thus, the water level in the upper part of the bearing can always be kept above a certain level,
The bearing sliding portion can be filled with lubricating water.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In addition, FIG.
The same parts as in FIG. 6 are denoted by the same reference numerals, and detailed description thereof will be omitted. FIG. 1 is a view showing one embodiment of the present invention. A generator 15 is directly connected to an upper portion of a water wheel 13 via a coupling 14, and a penstock 16 is connected to a casing 8. I have. An inlet valve 17 is provided on the penstock 16 near the casing 8, and a water supply pipe 18 is branched from the penstock 16 at an upstream side of the inlet valve 17. As shown in FIG. 2, the distal end of the water supply pipe 18 penetrates through the upper cover 4 and is opened at the lower part of the underwater bearing 3. An on-off valve 19 is provided in the water supply pipe 18. . When the on-off valve 19 is opened, the water in the penstock 16 is released from the bearing 3.
Automatically supplied to the bearing to lubricate the bearing.
Moreover, since the water supply pipe 18 is branched from the penstock 16 on the upstream side of the inlet valve 17, lubricating water can be reliably supplied to the bearing even when the turbine is stopped, that is, when the inlet valve 17 is closed. . Therefore, there is no need to provide facilities such as a water supply pump and a rapid filtration device for supplying lubricating water to the bearing portion as in the related art.

FIG. 3 is a view showing another embodiment of the present invention. An electric operation valve or an electromagnetic operation valve 20 is provided instead of the on-off valve 19. The opening and closing action of the solenoid operated valve is incorporated in the sequence at the time of starting and stopping the operation of the turbine. That is, the operation valve is opened several minutes to several tens of minutes before the start of rotation of the rotary shaft at the start of turbine operation, and is kept open from several minutes to several tens minutes after the stop of the rotary shaft at the time of stop of turbine operation. It is like that. Thus, lubricating water can be supplied to the bearing within a predetermined time before the start and stop of the rotating shaft,
The rotation of the rotating shaft without lubricating water is reliably prevented.

FIG. 4 is a view showing another embodiment, in which a water supply pipe 18 is provided with an electrically operated valve or an electromagnetically operated valve 20.
Is provided, and a flow meter 21 is provided. The electric operation valve or the electromagnetic operation valve 20 is controlled to open and close by a flow signal detected by the flow meter 21. That is, the amount of water flowing through the water supply pipe 18 is set, and the electrically operated valve or the electromagnetically operated valve 2 is controlled so as to reach the set flow rate.
0 is operated.

Accordingly, the flow rate of the lubricating water can always be set to a desired flow rate, and the occurrence of a shortage of the lubricating water is reliably prevented. As shown in FIG. 5, a space 2 outside the holding plate of the shaft water sealing device 6b and inside the upper cover 4 is provided.
2, a pressure sensor 23 may be installed, and the pressure sensor 23 may be used to open and close the electrically operated valve or the electromagnetically operated valve 20.

When the operation of stopping the operation of the water wheel or the like is stopped, the guide vane 11 is closed and the inlet valve 17 is closed, so that the water flowing to the runner 1 is cut off.
The place where there is no water temporarily becomes a negative pressure state. On the other hand, the turbine and the generator are rotating due to the inertial force, and the bearing 3
In order to prevent the lubricating water inside from leaking to the place where the pressure is negative, it is necessary to provide a multilayer seal 24 in the shaft sealing device 6b. However, in the present embodiment, since the pressure reduction state is sensed by the pressure sensor 23 and the electric operation valve or the electromagnetic operation valve 20 is opened and closed, a large amount of lubricating water is supplied according to the pressure reduction, Even if the lubricating water leaks from the seal 24, the lubricating water can be stably supplied to the bearing.

FIG. 6 is a view showing still another embodiment of the present invention, in which a second water supply pipe 25 is provided separately from a water supply pipe 18 from the penstock 16 upstream of an inlet valve 17 of the penstock 16. Is derived. This second water pipe 2
As shown in FIG. 7, the tip of 5 is opened in a space 22 inside the holding plate of the shaft water sealing device 6 b and inside the upper cover 4, and is opened and closed in the middle of the second water supply pipe 25. Valve 26
Is provided. By opening the on-off valve 26, water can be supplied to the space 22 even when the turbine is stopped, that is, even when the inlet valve 17 is closed.
The leakage of lubricating water from the part can be reduced.

By the way, as shown in FIG.
Instead of 6, an electrically operated valve or an electromagnetically operated valve 27 may be provided, and the opening / closing operation of the electrically operated or electromagnetically operated valve 27 may be incorporated into the sequence at the time of starting and stopping the operation of the turbine. . Thus, as in the case of the water supply pipe 18 shown in FIG. 3, the operation valve is opened a few minutes to several tens minutes before the rotation shaft starts to rotate, and is opened for a few minutes to several tens minutes after the operation of the turbine is stopped. In the meantime, the space 22 can be refilled with water. Also,
FIG. 9 is a view showing another embodiment shown in FIG. 8, in which a flow meter 28 is provided in the second water supply pipe 25, and a flow signal from the flow meter 28 supplies an electrically operated valve or a valve. The opening and closing operation of the electromagnetic operation valve 27 is performed.
Therefore, a predetermined flow rate of water can be supplied into the space 22 through the second water supply pipe 25. Further, the electrically operated valve or the electromagnetically operated valve 27 is provided with a pressure sensor 2 provided in the space 22 as shown in FIG.
The opening / closing operation may be performed by 3. Therefore, in this case, when the space 22 is to be brought into a negative pressure state during the operation of stopping the operation of the water turbine or the like, the electric operation valve or the electromagnetic operation valve 27 is opened and the hydraulic iron pipe 16 is inserted into the space 22. From the seal 24, and the amount of lubricating water leaking from the seal 24 can be reduced.

FIG. 10 is a view showing another embodiment of the present invention, in which a water supply pipe 1 branched and led out from a penstock 16 is shown.
An intake cover 29 that opens toward the upstream side of the penstock 16 is provided at the branch portion 8. Therefore, when the inlet valve 17 is closed, water can be taken into the water supply pipe 18 by the water pressure in the penstock 16, and when the inlet valve 17 is open, the penstock 16 is The flow direction of part of the water flowing inside is changed,
It is taken into the water supply pipe 18. Therefore, the inlet valve 17
It is possible to reliably supply a predetermined amount of lubricating water from the penstock 16 to the bearing portion irrespective of the open / closed state of the bearing.

In the above example, the water supply pipe 18 is provided with the water inlet cover 29 at the branch part. However, the water supply pipe cover may be provided at the branch part of the second water supply pipe 25. The amount of water supply into the space 22 can be secured.

FIG. 11 is a view showing still another embodiment of the present invention, in which a water supply pipe 18 inserted into a penstock 16 is provided.
Is provided with a slurry separator at the tip opening. That is, a truncated cone 31 is attached to the distal end opening of the water supply pipe 18 via the support plate 30. The truncated cone 31 has a shape that gradually expands toward the downstream side, and the water supply pipe 18 is provided between the rear end face of the truncated cone 31 and the front end opening of the water supply pipe 18.
An annular gap 32 is formed which opens in a direction perpendicular to the axis of.

However, the slurry having a large particle diameter mixed in the water flowing in the penstock 16 flows in the outer peripheral direction along the inclined surface of the truncated cone 31, and the slurry having the large particle diameter is separated from the separated water. From the annular gap 32 to the water supply pipe 18
And the water is supplied to the bearing. That is,
The annular gap 32 is small, and the cross section of the flow path in the portion where the truncated cone 31 is provided is reduced by the truncated cone 31. Water passing near the truncated cone 31 has a high flow velocity and is mixed into the water. The slurry is flowing in the outer peripheral direction of the penstock along the inclined surface of the truncated cone 31, and only the water at the center flows into the water supply pipe 18 from the annular gap 32. Therefore, the slurry having a large particle size does not flow to the bearing portion, and good bearing lubrication characteristics can be obtained.

FIG. 12 is a diagram showing a modification of FIG.
A water supply pipe 18 having a distal end inserted into the penstock 16 projects to the side of the penstock 16, and the penstock 16 is arranged substantially linearly. Therefore, the flow direction of the slurry-mixed water does not change at the branch portion of the water supply pipe 18, and the inflow of the slurry into the water supply pipe 18 can be further reduced.

FIG. 13 is a view showing still another embodiment of the present invention. A sleeve 33 is provided on the outer periphery of the rotating shaft 2 at a position facing the bearing 3.
Is coated with a cemented carbide material or ceramics. On the other hand, the inner peripheral surface of the bearing 3 is also coated with a cemented carbide material or ceramics 34.
It is itself formed of ceramics. Thus, by combining with the above embodiments, the wear resistance of the sleeve 33 and the bearing 3 can be further improved.

FIG. 14 is a view showing still another embodiment of the present invention, in which a water level sensor 35 is provided in the bearing housing 5 above the bearing 3. The detection signal of the water level sensor 35 causes the electric operation valve or the electromagnetic operation valve 20 to open and close. Therefore, when the bearing portion is not filled with the lubricating water, the electrically operated valve or the electromagnetically operated valve 20 is opened, the lubricating water is supplied to the bearing portion, and the bearing sliding portion is in a non-lubricated state. Nothing.

In each of the above embodiments, an example in which the same shaft sealing device 6b provided in the lower portion of the bearing 3 as the conventional one is used has been described. Since the lubricating water can be sufficiently secured, the shaft sealing device can be simplified, and the holding plate 36 of the shaft sealing device 6b can be reduced as shown in FIG. Therefore, the axial distance between the support part by the bearing 3 and the runner 1 can be shortened, and the shaft runout of the water turbine can be reduced.

[0032]

Since the present invention is constructed as described above, it does not require a water supply device for the bearing device, that is, a water supply pump or a rapid filtration device, and reliably supplies lubricating water to the bearing sliding surface. Thus, it is possible to prevent the bearing sliding portion from being in a non-lubricated state. Therefore, the shaft sealing device can be simplified, and the wear resistance of the bearing portion can be improved, and a high-performance and highly reliable underwater bearing device can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention.

FIG. 2 is a sectional view showing a configuration of a submerged bearing unit of the device shown in FIG.

FIG. 3 is a diagram showing another embodiment of the present invention.

FIG. 4 is a diagram showing still another embodiment of the present invention.

FIG. 5 is a sectional view showing a configuration of a submerged bearing according to another embodiment of the present invention.

FIG. 6 is a diagram showing another embodiment of the present invention.

FIG. 7 is a sectional view of the underwater bearing in the embodiment shown in FIG. 6;

FIG. 8 is a diagram showing another embodiment of the present invention.

FIG. 9 is a view showing another example of the embodiment of FIG. 8;

FIG. 10 is a sectional view showing an example of a water intake of a water supply pipe.

FIG. 11 is a sectional view showing an example in which a slurry separator is provided in a water supply pipe.

FIG. 12 is a view showing another modification of FIG. 11;

FIG. 13 is a cross-sectional view of a submerged bearing unit showing still another embodiment of the present invention.

FIG. 14 is a cross-sectional view of an underwater bearing according to still another embodiment of the present invention.

FIG. 15 is a cross-sectional view of an underwater bearing according to another embodiment of the present invention.

FIG. 16 is a sectional view showing a schematic configuration of a conventional underwater bearing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Runner 2 Rotating shaft 3 Bearing 5 Bearing housing 6a, 6b Shaft sealing device 8 Casing 16 Hydraulic iron pipe 17 Inlet valve 18 Water supply pipe 19, 26 On-off valve 20, 27 Electric or solenoid operated valve 21, 28 Flow rate Total 22 Space 23 Pressure sensor 24 Seal 25 Second water supply pipe 29 Intake cover 31 Truncated cone 32 Gap 35 Water level sensor

Claims (10)

[Claims] 1. A hydraulic machine such as a water wheel or a pump water wheel.
In an underwater bearing device using water as a lubricant, a water supply pipe having an on-off valve is branched and led out from an upstream side of an inlet valve of a penstock for supplying water to a runner chamber of the hydraulic machine, and the water supply pipe is provided therethrough. An underwater bearing device wherein water in a penstock is supplied to a bearing portion. 2. A second water supply pipe having an on-off valve is branched and led out from an upstream side of an inlet valve of the penstock, and water in the penstock is supplied to the outside of the shaft sealing device through the second water supply pipe. The underwater bearing device according to claim 1, wherein the underwater bearing device is supplied to a space between the upper cover and the inside of the upper cover. 3. The on-off valve is an electrically operated valve or an electromagnetically operated valve, and the on / off operation of the electrically operated valve or the electromagnetically operated valve is performed according to a sequence of starting and stopping the operation of the turbine. The underwater bearing device according to claim 1 or 2, wherein: 4. An on-off valve is an electrically operated valve or an electromagnetically operated valve, and said on / off valve is operated by a flow signal from a flow meter provided in said water supply pipe or the second water supply pipe. 3. The underwater bearing device according to claim 1, wherein the valve is operated to open and close. 5. The valve according to claim 1, wherein the on-off valve is an electrically operated or electromagnetically operated valve. The underwater bearing device according to claim 1, wherein the on-off control of an operation valve or an electromagnetic operation valve is performed. 6. The water in the penstock is supplied to the water supply pipe or the second water supply pipe by branching out the penstock from the penstock.
The underwater bearing device according to any one of claims 1 to 5, further comprising a water intake cover for guiding the water supply pipe toward the water supply pipe. 7. The water supply pipe and the second water supply pipe branched from the penstock are provided with a slurry separator for separating large foreign matters contained in water.
The underwater bearing device according to claim 1. 8. A slurry separator is provided such that a gap is formed between the slurry separator and a tip end of a water supply pipe inserted into a penstock so as to open in a direction perpendicular to an axis of the water supply pipe. The underwater bearing device according to claim 7, wherein the underwater bearing device is a truncated cone. 9. An outer peripheral surface of the rotary shaft facing the bearing is coated with a cemented carbide material or ceramics.
The underwater bearing device according to any one of claims 1 to 8, wherein the bearing surface of the bearing is coated with a cemented carbide material or ceramics, or the bearing is a ceramic bearing. 10. A water level sensor is provided in a bearing housing above a bearing, and an electric operation valve or an electromagnetic operation valve provided in a water supply pipe is opened and closed by a water level signal detected by the water level sensor. The underwater bearing device according to claim 1, wherein: