JPS61132775A - Pelton turbine - Google Patents

Abstract

PURPOSE:To prevent shifted abrasion of bearing metal or burning by providing means for pressure feeding lubricant to the sliding face of bearing metal in the functioning direction of shifted load under shifted load operation. CONSTITUTION:A bearing system 5 constructed with plural nozzles 3 and plural bearing metals 6 arranged in an oil tank 7 to bear the turbine spindle 1 is provided. Means 13 for pressure feeding the lubricant to the sliding face of bearing metal 6 in the functioning direction of shifted load functioning onto the bearing metal 6 under shifted load operation is provided. It can pressure feed the lubricant selectively to plural bearing metals. Upon elapse of predtermined time after starting of shifted load operation, pressure feeding of lubricant is stopped.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a Pelton water turbine that supports a water turbine main shaft by a segment type bearing device composed of a plurality of bearing metals, and particularly relates to a Pelton water turbine that supports a main shaft of the water turbine by a segment type bearing device composed of a plurality of bearing metals. This paper relates to a Pelton turbine that performs unbalanced load operation.

[Technical background of the invention and its problems]

Pelton water turbines are sometimes operated with only some of the plurality of nozzles open for the purpose of improving efficiency or adjusting output during partial load operation. In such operation, eccentricity occurs in the main shaft of the water turbine, and an eccentric load acts on the bearing metal that supports this main shaft. Such an unbalanced load is
It becomes particularly large during so-called single-shot operation, when only one nozzle is open and all other nozzles are closed.

If the magnitude of this unbalanced load becomes large enough to exceed the load capacity of the oil film between the main shaft and the bearing metal, the oil film will break, causing uneven wear or burnout of the bearing metal.

8 and 9 show a conventional Pelton water turbine, in which the main shaft 1 of the water turbine has a plurality of runners 2a.

2b, 2c, and 2d are fixed, and these runners 2
A, 2b, 2c, and 2d have a plurality of nozzles 3a on the outside,
3b, 3c, and 3d are arranged.

These nozzles 3a, 3b, 3G, 3(H, t) jet streams whose flow rates are controlled by needles 4a, 4b, 4c, and 4d, respectively, to the runners 2a, 2b, 2C, and 2d.

The main shaft 1 is supported by a bearing device 5, and this bearing device 5 has a segment composed of a plurality of bearing metals 6a, 6b, 6c, . This is a type of bearing. These bearing metals 6a, 6b, 6G, .

In such a Pelton turbine, during normal operation, approximately the same amount of water is ejected from each nozzle 3a, 3b, 3c, and 3d, and the load acting on the runners 2a, 2b, 2C, and 2d due to this water flow is radially are canceled out. For this reason, each bearing metal 6a, 6b.

5c, . support.

However, as shown in FIG. 9, only the nozzle 3a is opened for one jet operation, and the remaining nozzles 3b and 3c are opened.
, 3d are all closed, the main shaft 1 becomes eccentric and a large eccentric load F is continuously applied from the main shaft 1 to the bearing metal 6a. When such a large unbalanced load F acts continuously, the oil film on the sliding surface of the bearing metal 6a breaks down, causing solid contact between the main shaft 1 and the sliding surface of the bearing metal 6a, causing wear on the sliding surface and damage to the bearing metal. uneven wear may occur, and eventually burn-in may occur. In particular, when an oil film is not formed between the main shaft and the bearing metal sliding body at the start of unbalanced load motion, and there is a boundary lubrication state of complete solid contact or partial solid contact and partial fluid contact, When load operation is started, the bearing metal and the main shaft slide in solid contact in the direction in which the unbalanced load is applied, so that the uneven wear and seizure described above occur immediately after the start of operation.

[Purpose of the invention]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a Pelton water turbine that can reliably prevent wear and seizure of the bearing metal during uneven load operation.

[Summary of the invention]

In order to achieve this object, the present invention includes a plurality of nozzles and a bearing device configured from a plurality of bearing metals provided in an oil tank and bearing the main shaft of the water turbine. A Pelton water turbine on which an unbalanced load acts, is characterized by comprising a lubricating hydraulic pressure sending means for pumping lubricating oil to the sliding surface of the bearing metal in the direction in which the unbalanced load acts during the unbalanced load operation.

[Embodiments of the invention]

An embodiment of a Pelton water turbine according to the present invention will be described below with reference to FIGS.
This will be explained with reference to the figures.

1 and 2 show an embodiment of a Pelton water turbine according to the present invention, in which a main shaft 1 of the water turbine has a plurality of runners 2a,
2b, 2G, 2d are fixed, and these runners 2a, 2
A plurality of nozzles 3a, 3b are arranged around the outer circumference of b, 2c, 2d.
, 3c, and 3d are arranged. These nozzles 3a,
3b, 3c.

3d is a jet flow controlled by needles 4a, 4b, 4c, and 4d, respectively, from runners 2a, 2b, 2c, and 2.
d and rotate the main shaft 1.

The main shaft 1 is supported by a bearing device 5, and this bearing device 5
This is a segment type bearing consisting of a plurality of bearing metals 6a, 6b, 6C, 6d, . . . , 6h arranged with small gaps between them and the main shaft 1. These bearing metals 5a, 5b, 5c.

... 6h is immersed in lubricating oil 8 in oil tank γ, and this lubricating oil 8 is cooled by cooling corrugated pipe 9.

An oil supply hole 10 is drilled in the bearing metal 6a on which an unbalanced load F acts during unbalanced load operation. This oil supply hole 10 penetrates the bearing metal 6a and opens at its sliding surface. A feed oil pipe 11 is connected to this oil supply hole 10, and this feed oil pipe 11 is connected to a lubricating oil circulation device 13 such as a pump via an automatic opening/closing device 12 such as a solenoid valve. The lubricating oil circulation device 13 and the oil tank 7 are connected by a return oil pipe 14. This return oil pipe 14 is also provided with an automatic opening/closing device 15 such as a solenoid valve. The control device 16 controls the oil supply pressure and flow of the lubricating oil circulation device 13, and also controls the opening and closing of the automatic opening devices 12 and 15. Oil supply hole 1
0, the oil pipes 11 and 14, the automatic opening/closing devices 12 and 15, the lubricating oil circulation device 13, and the control device 16 constitute a lubricating hydraulic pressure sending means that pumps lubricating oil from the oil supply hole 10 to the sliding surface of the metal 6a.

Next, the operation of the apparatus according to the present invention described above will be explained.

During normal operation when all nozzles 3a, 3b, 3c, 3d are opened and then approximately the same amount of water is injected, the control device 16 stops the lubricating oil circulation device 13 and closes the automatic opening devices @12 and 15. . Therefore bearing metal 6
There is no pressure feeding of lubricating oil from the oil supply hole 10 of a, and the main shaft 1 is
It is supported only by the oil film wedge action between the sliding surfaces of each bearing metal 6a, 6b, 6c, . . . 6h.

As shown in FIG. 2, during unbalanced load operation with only the nozzle 3a open, the control device 16 commands the driving of the lubricating oil circulation device 13 and the opening of the automatic opening/closing devices 12 and 15.

In response to this command, the lubricating oil 8 in the oil tank 7 is pumped by the H1Wi oil circulation device 13 through the oil supply hole 10 through the return oil pipe 14 and the feed oil pipe 11 to the sliding surface of the bearing metal 6a. The load bearing capacity of the oil film due to the wedge effect of the oil film on the sliding surface of the bearing metal 6a is greatly improved by the pressure oil in the oil supply hole 10. Therefore, even if a high unbalanced load is applied from the main shaft 1 to the bearing metal 6a during unbalanced load operation, the main shaft 1
An oil film is always formed between the sliding surfaces of the bearing metal 6a and the sliding surface of the bearing metal 6a, and a fluid lubrication state is maintained, thereby preventing damage and seizure of the bearing metal 6a.

The oil pressure supplied from the oil supply hole 10 is adjusted by controlling the opening degree of the automatic opening/closing device 12.15 and the pressure and flow rate from the lubricating oil circulation device 13 according to the magnitude of the unbalanced load acting on the bearing metal 6a. Ru.

Note that the unbalanced loads in the same direction as above are applied to the nozzles 3a and 3b.

This also occurs when three bearings 3d are opened, but in this case as well, the bearing metal 6 is
This prevents damage and burn-in of a.

The above-mentioned embodiment was effective only when the acting direction of the unbalanced load was always constant, but next, another embodiment that is effective even when the unbalanced load acts in any direction is shown in Fig. 3. explain.

In Fig. 3, bearing metals 5a, 6b,...6h
Oil supply holes 10a, . . . 10h are drilled in all of the oil pipes 11a, .
・11h, automatic opening device 12a, ・Connected to the annular common pipe 17 via the 12h, and this annular common oil pipe 17
is connected to the lubricating oil circulation device 13 via a common oil pipe 18 and a common automatic opening/closing device 19. The return oil pipe 14 and automatic opening/closing device 15 are the same as those shown in FIG. The control device 16 controls all automatic opening/closing devices 12a, 12h, 1
5.19 and the circulation device 13.

With this configuration, when a certain nozzle is opened to perform unbalanced load operation, the control device 16 pumps lubricating oil to the oil supply hole of one or more bearing metals located in the direction in which the unbalanced load acts. Therefore, the individual automatic opening/closing device 12a,...
12h corresponding to the bearing metal is selected and opened, the circulation device 13 is driven, and the common automatic opening/closing device 15.19 is opened. As a result, lubricating oil is pumped only to the sliding surface of the bearing metal in the direction in which the unbalanced load is applied. This supply oil pressure is adjusted by controlling the opening degrees of the automatic opening/closing devices 12a, . . . , 12h according to the magnitude of the load that each bearing metal should bear.

In this way, even if the direction of action of the unbalanced load changes due to changing the selection of nozzles to be opened, this can be handled by selectively opening and closing the individual automatic opening/closing devices 12a, . . . 12h.

Even in unbalanced load operation, if the magnitude of the unbalanced load is relatively small, the unbalanced load can be supported only by the oil film pressure generated by the wedge effect between the sliding surface of the bearing metal and the main shaft. However, when the water turbine is started, no oil film pressure is generated between the main shaft and the sliding bearing metal, resulting in a solid contact state or a boundary lubrication state in which some solid contact and some fluid contact occur. Therefore, in the case of unbalanced load operation where the unbalanced load is relatively small, lubricating oil is force-fed to the sliding surface of the bearing metal where the unbalanced load acts by commands from the control device 13 only at startup, and after a predetermined period of time has elapsed, the water turbine is The pumping of the lubricating oil may be stopped when the rotational speed increases and the oil film pressure due to the wedge effect becomes sufficiently large.

FIG. 4 shows an example in which a part of the oil pipe 11 connected to the oil supply hole 10 of the bearing metal 6 is made into a flexible pipe 20, and this flexible pipe 20 is interposed in the oil pipe 11 near the bearing metal 6. ing. By installing the flexible pipe 20, the bearing gap between the main shaft 1 and the bearing metal 6 can be easily finely adjusted when installing the water turbine. The bearing metal 6 is configured so that it can be rotated to some extent with respect to the bearing metal support portion 21 in order to increase the oil film pressure due to the wedge effect during rotation of the main shaft 2. If the flexible tube 20 were not present, the rotational displacement of this bearing metal would be restricted by the oil tube 11, but the presence of the flexible tube 20 frees the rotational displacement.

Fig. 5 shows an embodiment of a Pelton water turbine according to the present invention, which is equipped with a forced lubrication type bearing device, and each bearing metal 6a, . . . has an oil supply hole 10a1, . , each oil supply hole 10a,... has an oil pipe 11a,...
・ are connected, and each oil pipe 11a, . . . is connected to the automatic opening/closing device 1.
2a, . . . are connected to a lubricating oil circulation device such as a pump (not shown). Bearing metal 6a,...
The lower oil receiver 22 is connected to the circulation system by a return pipe 14.

The automatic opening/closing device 12a1... and the circulation device are controlled by a control device not shown.

During normal operation, each bearing metal 5a,
All sliding surfaces of ... are supplied with lubricating oil at the same pressure and flow rate.

During unbalanced load operation, the control device operates the automatic opening/closing devices 12a, .
... by changing the opening degree of each corresponding bearing metal 6a, ..., and adjusting the oil pressure and flow rate to the sliding surface of the bearing metal so that the resultant force of the oil pressure supplied to each bearing metal is in the opposite direction to the acting direction of the unbalanced load. The individual bearing metal 6a.

...Changes each time. Specifically, the oil pressure is set to be large and the flow m is large for the bearing metal in the direction in which the unbalanced load is applied, and the oil pressure and the flow rate are set to be small for the bearing metal in the opposite direction.

Of course, the flexible tube 20 shown in FIG. 4 can also be installed in this forced lubrication type bearing device.

Fig. 6 shows an example in which gap sensors 23a, . . . 23h are installed on each bearing metal 6a, . The spring sensors 23a, . . . , 23h detect passage of the bearing clearance between the corresponding bearing metals 6a, .

The rest of the configuration is the same as the configuration shown in FIG.

When the unbalanced load operation is started, for example, as shown in the figure, the unbalanced load F acts intermittently on the bearing metal 6a, and the amount of bearing clearance there decreases. When the control device 116 determines from the detection outputs of the gap sensors 23a, . The lubricating oil is force-fed to the sliding surface of the bearing metal 6a by controlling the opening/closing device 12a, etc. During normal operation, the bearing clearance between the bearing metals is instantaneously reduced, but this does not continue, so the above-mentioned lubricating oil is not pumped.

Figure 7 shows temperature sensor 2 on bearing metal 6a,...6h.
4a, . . . 24h are provided, and each temperature sensor 24a, . . . 24h is connected to a corresponding bearing metal 5.
The temperatures of the sliding surfaces of a, . . . , 6h are detected and sent to the control device 16. The rest of the configuration is the same as the configuration shown in FIG.

When the unbalanced load operation is started, the bearing clearance of the bearing metal on which the unbalanced load F acts decreases, the loss there increases rapidly, and the sliding surface temperature also increases rapidly. The control device 16 determines the occurrence J3 of the unbalanced load F and the direction of its action from the detection outputs of the temperature sensors 2, 4a, . to prevent damage to the bearing metal.

These gap sensors and temperature sensors can be attached to the forced lubrication type bearing device shown in FIG. 4, or both types of sensors can be used in combination.

[Effects of the Invention] As is clear from the above description, according to the present invention, since lubricating oil is pumped to the sliding surface of the bearing metal where uneven loads act, uneven wear and seizure of the bearing metal due to uneven loads can be prevented. It can be prevented.

[Brief explanation of the drawing]

Figures 1 and 2 each show an embodiment of a Pelton turbine according to the present invention. i-side view and cross-sectional view, 3rd
The figure is a cross-sectional view showing another embodiment, FIGS. 4 and 5 are longitudinal sectional views showing other embodiments, and FIGS. 6 and 7 are respectively showing different embodiments. l Cross-sectional views, Figures 8 and 9
The figures are a vertical cross-sectional view and a cross-sectional view, respectively, showing a conventional Pelton water turbine. DESCRIPTION OF SYMBOLS 1... Water turbine main shaft, 3... Nozzle, 5... Bearing device, 6... Bearing metal, 7... Oil tank, 8... Lubricating oil, 10... Oil supply hole, 11... - Oil pipe, 12... automatic opening/closing device, 13... lubricating oil circulation device, 16... control device, 23... gap sensor, 24... temperature sensor. Applicant's agent Kiyoshi Inomata Figure 2, Figure 3 [! 1 Figure 5 Figure 6 Figure 7

Claims (1)

[Scope of Claims] 1. A bearing device comprising a plurality of nozzles and a plurality of bearing metals provided in an oil tank and supporting the main shaft of the water turbine, wherein an unbalanced load is applied to the bearing metal during unbalanced load operation. 1. A Pelton water turbine, characterized in that the Pelton water turbine is equipped with a lubricating hydraulic pressure sending means for pumping lubricating oil to the sliding surface of the bearing metal in the direction in which the unbalanced load acts during the unbalanced load operation. 2. The lubricating oil pressure sending means is capable of pumping lubricating oil to all of the plurality of bearing metals, and selectively pumps lubricating oil to the bearing metals in the direction in which the unbalanced load acts during the unbalanced load operation. A Pelton water turbine according to claim 1, characterized in that: 3. The Pelton water turbine according to claim 1 or 2, wherein the lubricant hydraulic pressure feeding means stops the pressure feeding after a predetermined time has elapsed from the start of the unbalanced load operation. 4. The lubricant oil pressure sending means has a lubricant oil feed vibrator connected to the bearing metal, and the pipe is constructed of a flexible pipe in the vicinity of the bearing metal. The Pelton water turbine according to any one of items 1 to 3. 5. A bearing device comprising a plurality of nozzles and a plurality of bearing metals and bearing the main shaft of the water turbine, and a forced oil supply device for forcibly supplying lubricating oil to each of the sliding surfaces of the plurality of bearing metals. In a Pelton water turbine in which an unbalanced load acts on the bearing metal during unbalanced load operation, the resultant force of the hydraulic pressure applied to each sliding surface of the bearing metal acts in the opposite direction to the acting direction of the unbalanced load during the unbalanced load operation. A Pelton water turbine characterized in that it is equipped with a control device for controlling oil pressure supplied to the metal sliding surface of the bearing. 6. The Pelton water turbine according to claim 5, wherein the control device performs the oil pressure control after a predetermined time has elapsed from the start of the unbalanced load operation. 7. The forced oil supply device has a pipe for supplying the lubricating oil to the sliding surface of the bearing metal, and the pipe is constructed of a flexible pipe in the vicinity of the bearing metal. Pelton water turbine according to paragraph 5 or paragraph 6. 8. In a Pelton water turbine that is equipped with a plurality of nozzles and a bearing device that is composed of a plurality of bearing metals and supports the main shaft of the water turbine, and in which an uneven load acts on the bearing metal during operation with an uneven load, A detection means for detecting the occurrence of a load, and a means for generating supply oil pressure in a direction opposite to the uneven load by force-feeding lubricating oil to at least the bearing metal sliding surface on which the uneven load acts according to the detection output of the detection means. A Pelton water wheel characterized by comprising: 9. The detection means includes a gap sensor that detects the amount of gap between the bearing metal sliding surface and the water turbine main shaft,
The Pelton water turbine according to claim 8, wherein the detection output is generated when the gap amount becomes smaller than a predetermined value. 10. Claim 8, wherein the detection means includes a temperature sensor that detects the temperature of the bearing metal sliding surface, and generates the detection output when the temperature exceeds a predetermined value. Pelton water turbine as described in section.