JP2009041482A - Hydraulic machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydraulic machine not susceptible to breakage or dropping off caused by a force received by fluid and having a straightening member excellent in ease of mounting work. <P>SOLUTION: The straightening member 9 of the hydraulic machine has an arc-like cross-sectional shape, and is fixed to an outer periphery of a stay ring 4, so that a projection part of the arc directs on a flow passage 3a side of the casing 3. A support member 11 is fixed to the outer periphery of the stay ring 4, and the straightening member 9 is fixed to the support member 11. In this way, since the straightening member 9 has structure held by the stay ring 4 not connected with the casing 3 and does not transmits the force received by the straightening member 9 to the casing 3, the breakage of the casing 3 or the dropping off of the straightening member 9 is suppressed, and the installation is performed only by relatively simple process, that is, welding. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a hydraulic machine.

  In general, hydraulic machines such as water turbines and pump turbines used for hydroelectric power generation are renewed in order to repair aging deterioration, earth and sand wear, damage due to corrosion, etc. due to many years of operation, and to improve the characteristics of hydraulic machines. Is. However, in the case of hydroelectric power generation, for example, many of the main parts of the hydropower machine are embedded parts such as concrete, so the work area (space) is often limited in renewal work, and renewal work takes a lot of time. There is. For this reason, the range of repairs and updates is often limited for the purpose of reducing maintenance costs, etc. Therefore, it is desirable to reduce the number of update operations as much as possible.

When used for hydroelectric power generation, a hydraulic turbine, which is a hydraulic machine, flows water flowing down from a storage facility such as a dam or pond in a high place as pressure water into the casing in which the flow path is formed, and the turbine is connected via a staying ring. The structure has a structure in which water is introduced to a runner provided in the rotating body and the rotating body is rotated.
The casing forms a flow path, for example, in a circular shape so as to surround the periphery of the rotating body, and the staying allows water flowing through the casing to flow through the casing by a space formed between upper and lower substantially disk-shaped plates. This structure leads to the runner. The upper and lower plate members forming the staying are supported by a plurality of stay vanes to maintain the structural strength. Then, the upper and lower plate members forming the staying are fixed to the casing by means such as welding, and the front end portion thereof is fixed in a state protruding from the casing flow path in order to maintain the structural strength.

  In hydroelectric power generation, in small water turbines used in facilities where the drop of water flowing from the storage facility is small, the rectifying action can be increased by arranging the upper and lower plate members inclined from the casing toward the runner. Mold staying can be used. However, it is difficult to use bellmouth type staying for large turbines used in equipment with large water drop from the viewpoint of structural strength, so parallel plate type with upper and lower plate members arranged in parallel Staling is often used. Parallel plate type staying has less rectifying action than bell mouth type staying.For example, when flowing into the staying from the casing, the flow is disturbed at the part where the outer peripheral edge of the staying protrudes into the case. As a result, fluid loss increases, leading to performance degradation.

  Therefore, in order to suppress the occurrence of turbulence when flowing from the casing into the staying, a technique is disclosed that includes a rectifying member on the outer periphery of the staying (see, for example, Patent Document 1).

  However, for example, the rectifying member disclosed in Patent Document 1 is subjected to fluctuating stress due to the pressure of the pressure water flowing through the flow path of the casing. And when this fluctuating stress acts on the rectifying member over a long period of time, the joint portion of the rectifying member, for example, with the staying, may be fatigued.

Therefore, a region surrounded by the rectifying member, the staying, and the casing is filled with a filler such as concrete milk for reinforcement. By filling the filler such as concrete milk in this way, it is possible to prevent the fluctuating stress from acting on the rectifying member.
JP 2002-147327 A (see paragraph 0022, FIG. 3)

  As described above, by filling with a filler such as concrete milk, it is possible to prevent the fluctuating stress from acting on the rectifying member. However, the work for filling the filler and the hardening of the filler requires a considerable time. Problems such as deterioration of sex are known.

  Then, this invention makes it a subject to provide the hydraulic machine which has the baffle member which was hard to generate | occur | produce the failure | damage and drop | offset by the force received from pressure water, and was excellent in attachment workability | operativity.

  In order to solve the above-described problems, the present invention is characterized by including a rectifying member that has a non-restraining portion and is fixed to the staying by a support member.

  ADVANTAGE OF THE INVENTION According to this invention, the hydraulic machine which has the baffle member which was hard to generate | occur | produce by the force received from pressure water, and was excellent in attachment workability | operativity can be provided.

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings as appropriate.
First, a conventional structure will be described with reference to FIGS. 1 and 2 for comparison. FIG. 1 is a schematic cross-sectional view of a Francis turbine used for hydroelectric power generation, and FIG. 2 is a diagram showing that a conventional rectifying member is attached.

  As shown in FIG. 1, the Francis turbine 1 that is a hydraulic machine has a rotating body 2 that rotates around a rotating shaft 2 a connected to the generator G, and the rotating body 2 by rotatably holding the rotating shaft 2 a. By fixing the rotating part 2 so as to surround the rotating body 2 in a downwardly inclined manner, the rotating part 2 is provided with a water guide channel 5d that guides the pressure water flowing through the flow path 3a of the casing 3 to the rotating body 2. A stirring 4 including a casing 3 that forms a spiral-shaped channel 3a having a circular cross section and a water conduit 4c that guides the pressure water flowing through the channel 3a of the casing 3 to the water conduit 5d of the fixed portion 5. Consists of including.

  As indicated by the arrows, the pressure water flowing through the flow path 3 a of the casing 3 is guided to the rotating body 2 through the water guide path 4 c of the staying 4 and the water guide path 5 d of the fixing portion 5, and rotates the rotating body 2. To do. The pressure water that has rotated the rotating body 2 is discharged to a lower pond or the like via a suction pipe 5c that opens to the lower portion of the fixed portion 5.

As shown in FIG. 1, the staying 4 is formed by an upper plate 4a and a lower plate 4b. The outer peripheral edges of the upper plate 4 a and the lower plate 4 b are substantially circular when viewed from above, and are provided connected to the inner periphery of the casing 3. And the upper board 4a and the lower board 4b are arrange | positioned in parallel relatively, and the water conduit 4c is formed among them.
A stay vane 8 is fixed between the upper plate 4a and the lower plate 4b by means such as welding to maintain the strength of the staying 4. The stay vane 8 is a plate-like member, for example, and is provided from the outer peripheral edge side of the staying 4 toward the center side of the rotating body 2, and the upper end portion and the lower end portion are fixed to the upper plate 4a and the lower plate 4b, respectively. Is done. Note that the end of the stay vane 8 on the center side of the rotating body 2 may be fixed by being inclined in the direction of the flow of the pressure water flowing through the casing 3 from the end on the outer peripheral edge side of the stay ring 4. That is, an inclination is provided in the direction of flow from the outer peripheral edge side of the staying 4 toward the center side of the rotating body 2. Thus, the efficiency of the water conveyance from the casing 3 to the staying 4 is improved by providing the stay vane 8 with an inclination toward the flow direction. The staying 4 is preferably provided with a plurality of stay vanes 8 in the circumferential direction.

  The upper plate 4a and the lower plate 4b of the staying 4 are respectively fixed to the casing 3 by means of welding or the like, and a side surface of the casing 3 is opened between the upper plate 4a and the lower plate 4b so that the staying 4 is guided. The water channel 4 c communicates with the channel 3 a of the casing 3. With such a configuration, the pressure water flowing through the flow path 3 a of the casing 3 can flow into the water conduit 4 c of the staying 4.

  The fixing portion 5 includes an upper cover 5a and a lower cover 5b that form a water conduit 5d. The upper plate 4a and the upper cover 5a of the staying 4 are fixed in a watertight manner, and the lower plate 4b and the lower cover 5b are fixed in a watertight manner. Is done. With such a configuration, the water conduit 4c of the staying 4 communicates with the water conduit 5d of the fixed portion 5, and the pressure water flowing through the water conduit 4c of the staying 4 flows into the water conduit 5d of the fixed portion 5. Become.

  The fixed portion 5 is provided with a guide vane 7 that is rotatable around a rotary shaft 7a that is held by the upper cover 5a and the lower cover 5b and extends in the vertical direction. The guide vane 7 is a plate-like member, and rotates (swings) perpendicularly to the direction of the pressure water flowing through the water conduit 5d of the fixing part 5, and the rotation angle (swinging angle) of the fixing part 5 It has a function of adjusting the amount of water flowing through the water conduit 5d.

  The rotating body 2 is formed with an opening so as to communicate with a water conduit 5d formed in the fixed portion 5, and the opening is provided with a plurality of runners 2b. Then, when the pressure water flowing through the water guide channel 5d of the fixed portion 5 hits the runner 2b, the pressure energy and velocity energy of the pressure water are converted into rotational kinetic energy, and the rotating body 2 rotates.

In the Francis turbine 1 configured as described above, the staying 4 and the casing 3 are joined by welding as described above. At this time, in consideration of the structural strength, the casing 3 is preferably welded to the stay ring 4 at the upper part of the stay vane 8 that supports the upper plate 4 a and the lower plate 4 b, and is joined to the inner side of the outermost periphery of the stay ring 4. A part is made. Therefore, as shown in FIG. 1, the outer peripheral edge of the staying 4 protrudes into the flow path 3 a formed inside the casing 3.
Then, the flow of pressure water is disturbed by the outer peripheral edge of the staying 4 protruding into the flow path 3 a of the casing 3, and fluid loss occurs when the pressure water flows from the flow path 3 a of the casing 3 into the water conduit 4 c of the staying 4. Becomes larger.

  Therefore, conventionally, as shown in FIG. 2, a rectifying member 9 is provided on the outer peripheral edge of the staying 4 protruding into the flow path 3 a of the casing 3. The rectifying member 9 is, for example, a plate-like member that is curved so as to draw an arc from one end to the other end of the cross-sectional shape, and is arranged so that the convex surface faces the flow path 3a side of the casing 3, and one end of the rectifying member 9 is The front end of the outer peripheral edge of the ring 4 is fixed by welding or the like, and the other end is fixed to the inside of the casing 3 by welding or the like. By providing such a rectifying member 9, the pressure water smoothly flows from the flow path 3 a of the casing 3 to the water guide path 4 c of the staying 4, thereby suppressing the occurrence of flow disturbance.

However, in the casing 3 shown in FIG. 2, a force directed from the pressure water flowing through the flow path 3 a to the outside of the flow path 3 a acts. Therefore, the rectifying member 9 fixed as shown in FIG. A force directed outward from the pressure water flowing through the flow path 3a acts. Since most of these forces change over time, the rectifying member 9 acts as a fluctuating stress and contributes to fatigue failure.
In order to prevent such fatigue failure, a filler 10 such as concrete milk is filled in an area surrounded by the casing 3, the staying 4, and the rectifying member 9 as shown in FIG. 2. By filling the filler 10 in this way, the fluctuating stress acting on the rectifying member 9 can be suppressed. Further, even if fluctuating stress is applied, the stress is not concentrated because it is dispersed by the filler 10, and it is possible to prevent breakage due to stress concentration.
However, as described above, the man-hour for filling the filler 10 is required, and there is a problem that work efficiency is deteriorated because a considerable time is required for curing the filler 10.

  Therefore, the present embodiment is characterized by a rectifying member that has an unconstrained portion and is fixed to the staying by a support member. (A) of FIG. 3 is a figure which shows the rectification | straightening member concerning this embodiment in a Francis turbine, (b) is a perspective view of the XX cross section in (a) of FIG. 3, FIG. 4 is FIG. In the perspective view of the XX section in (a), it is a figure showing fixing the straightening member formed with the linear member. In addition, about the member equivalent to the Francis turbine shown to FIG. 1 and FIG. 2, the same code | symbol is attached | subjected and description is abbreviate | omitted suitably.

  As shown to (a) of FIG. 3, the rectification | straightening member 9 concerning this embodiment is a plate-shaped member which cross-sectional shape makes an arc shape, for example, Comprising: A convex surface faces the flow-path 3a side of the casing 3. As shown in FIG. It is arrange | positioned and one end is welded and fixed so that the welding part 9a may be formed in the front-end | tip of the outer periphery of the staying 4. FIG. And as shown to (a) of FIG. 3, at least one end of the rectification | straightening member 9 is in the open state, without being fixed. That is, the rectifying member 9 has a non-binding portion and is held on the outer peripheral edge of the staying 4 so as not to be connected to the casing 3.

  Further, the rectifying member 9 is provided with a support member 11 on the arc-shaped concave surface side. The support member 11 is a plate-like member provided in a rib shape from one end side to the other end side of the rectifying member 9 fixed to the distal end portion of the outer peripheral edge of the staying 4, and one end thereof is a casing. 3 is fixed by means such as welding to form a welded portion 11a on the outer peripheral edge of the staying 4 protruding into the flow path 3a. That is, the rectifying member 9 is fixed to the support member 11 that is fixed to the outer peripheral edge of the staying 4. And, like the flow regulating member 9, the other end is not fixed and has a non-restraining portion, and is held on the outer peripheral edge of the staying 4 so as not to be connected to the casing 3.

  Although one end of the rectifying member 9 is fixed to the tip of the outer peripheral edge of the staying 4, this is not limited, and the rectifying member 9 is not fixed to the tip of the outer peripheral edge of the staying 4. The structure fixed only to the support member 11 may be sufficient. In this case, the rectifying member 9 is held on the staying 4 only by the support member 11.

  As described above, since the rectifying member 9 and the support member 11 are not connected to the casing 3, the rectifying member 9 is installed so as not to be connected to the casing 3.

  Here, the number of the supporting members 11 is not limited, and if the supporting members 11 are appropriately installed based on the magnitude of the fluctuating stress acting on the rectifying member 9 and the strength required for the rectifying member 9. Good.

The rectifying member 9 formed as shown in FIG. 3 (a) is held in a cantilever state only by the staying 4, and the rectifying member 9 and the casing 3 are not connected. Does not touch directly. Therefore, even if fluctuating stress is generated in the rectifying member 9 due to the flow of pressure water, it is not transmitted to the casing 3.
In general, since the member of the casing 3 is thinner and weaker than the staying 4 for weight reduction and the like, the fluctuating stress from the rectifying member 9 is not transmitted to the casing 3 having a lower strength. This will improve the durability.

Furthermore, since the casing 3 is a thin member as described above, the cross-sectional shape repeatedly expands and contracts minutely with changes in the pressure of the pressure water flowing through the flow path 3a. For example, when the casing 3 and the rectifying member 9 are connected as shown in FIG. 2 as in the conventional technique, the joint portion between the casing 3 and the rectifying member 9 is obtained by minute expansion / contraction of the sectional shape of the casing 3. Since stress concentration occurs in the surface, there is room for improvement in terms of strength.
On the other hand, in the present embodiment, as shown in FIG. 3A, the rectifying member 9 and the casing 3 are not connected, so that the rectification is performed by repeating minute expansion / reduction of the cross-sectional shape of the casing 3. The stress is not concentrated on the connecting portion between the member 9 and the casing 3, and the connecting portion is not damaged. Thus, in this embodiment, there exists an outstanding effect that damage does not generate | occur | produce in the junction part of the casing 3 and the rectification | straightening member 9.

Moreover, since the rectifying member 9 according to the present embodiment does not weld with the casing 3, it is possible to reduce the number of man-hours required for welding. Therefore, it is necessary to install or repair the Francis turbine 1 (see FIG. 1). The construction period can be shortened.
And since the rectifying member 9 is fixed to the staying 4 by the support member 11 as shown in FIG. 3A, the fluid reaction force from the pressure water flowing through the flow path of the casing 3 can be supported. The filler 10 such as concrete milk (see FIG. 2) is not necessary. Accordingly, the man-hour for filling the filler 10 and the waiting time until the filler 10 is hardened can be reduced, so that the time for installing and repairing the Francis turbine 1 can be shortened.

As shown in FIG. 3 (a), the method of attaching the rectifying member 9 is not limited. However, when the diameter of the casing 3 is large enough for the worker to work in, the worker, for example, 3, the support member 11 is fixed to the outer peripheral edge of the staying 4 to which the casing 3 is fixed in advance by a method such as welding, and the rectifying member 9 is fixed to the support member 11 by a method such as welding. A method is conceivable.
In this embodiment, since it is not necessary to fix (weld) the rectifying member 9 to the inside of the casing 3, the support member 11 is previously welded to the outer peripheral edge of the staying 4 in a state where the casing 3 is not fixed. A method of fixing the casing 3 after fixing the rectifying member 9 to the support member 11 by a method such as welding is also conceivable.

  Here, the shape of the straightening member 9 in the longitudinal direction will be considered. As shown in FIG. 3 (b), the straightening member 9 is provided along the outer wall of the casing 3 and the outermost periphery of the staying 4, so the longitudinal direction of the straightening member 9 is the outer wall of the casing 3 and the staying 4. It bends with the same radius of curvature as the outermost circumference. In particular, as shown in FIG. 2, when the filler 10 such as concrete milk is filled in the area surrounded by the casing 3, the staying 4 and the rectifying member 9, the area filled with the filler 10 is sealed. Therefore, the straightening of the straightening member 9 so that the straightening member 9 is in close contact with the staying 4 and the casing 3, that is, no gap is formed between the straightening member 9 and the staying 4 and the casing 3. It is necessary to bend the direction.

  On the other hand, in this embodiment, the rectifying member 9 is fixed to the staying 4 via the support member 11 and the rectifying member 9 does not need to be in close contact with the staying 4 and the casing 3. As shown in FIG. 4, the straightening member 9 may be formed by joining linearly formed members.

  The rectifying member 9 can be formed using, for example, a member having a semicircular cross section obtained by cutting a hollow pipe member in the longitudinal direction. And as shown in FIG. 4, in order to join a linear member and form the rectification | straightening member 9, what is necessary is just to cut | disconnect a member with a semicircular cross section suitably, and to join by welding etc., for example. This makes it easier to work on a member having a semicircular cross-section than bending it in the longitudinal direction into a shape along the outer wall of the casing 3 and the outermost periphery of the staying 4 as shown in FIG. The flow regulating member 9 can be formed in the process. Therefore, workability is improved, and an excellent effect is achieved that the work period for installing and refurbishing the Francis turbine 1 (see FIG. 1) can be shortened and the production cost can be reduced.

The rectifying member 9 (see FIG. 3A) is attached to the stay ring 4 (see FIG. 3) protruding into the flow path 3a (see FIG. 3A) of the casing 3 (see FIG. 3A). (A) may be provided over the entire circumference of the outer peripheral edge, or a structure in which the rectifying member 9 is provided only at a part of the outer peripheral edge of the staying 4 may be employed.
The pressure water flowing through the casing 3 has a higher flow rate and a higher pressure in the upstream portion than in the downstream portion. Therefore, the upstream part has a larger amount of water flowing from the flow path 3a to the water conduit 4c of the staying 4 than the downstream part, and the flow generated when pressure water flows from the flow path 3a to the water guide path 4c of the staying 4 Disturbance is also likely to occur. For this reason, for example, the rectifying member 9 may be provided only in the upstream portion of the casing 3 without being provided over the entire circumference of the outer peripheral edge of the staying 4.
Furthermore, the form which equips either the upper board 4a (refer (a) of FIG. 3) or the lower board 4b (refer (a) of FIG. 3) with the baffle member 9 may be sufficient.

As mentioned above, although the example which applied the straightening member 9 (refer FIG. 3) concerning this invention to the Francis turbine 1 (refer FIG. 1) was shown, application of the straightening member 9 concerning this invention is limited to the Francis turbine 1 is not.
5 is a diagram showing an example in which the rectifying member according to the present invention is applied to a Francis pump turbine, and FIG. 6 is a diagram showing an example in which the rectifying member according to the present invention is applied to a mixed-flow turbine. These are figures which show the example which applied the baffle member concerning this invention to the Kaplan turbine.

As shown in FIG. 5 to FIG. 7, even if the used turbines are different types such as Francis pump turbine 1a (see FIG. 5), mixed flow turbine 1b (see FIG. 6) and Kaplan turbine (see FIG. 7). Since the shape of the joint between the staying 4 and the casing 3 is the same as that of the Francis turbine 1 shown in FIG. 1, the outer peripheral edge of the staying 4 protrudes into the flow path 3 a of the casing 3.
Therefore, for example, the rectifying member 9 having the same shape as the rectifying member 9 shown in FIG. And the same effect as the case of the Francis turbine 1 (refer FIG. 1) that an improvement of workability | operativity, shortening of a work period, and reduction of production cost is possible is produced.

It is a schematic sectional drawing of the Francis turbine used for hydroelectric power generation. It is a figure which shows having attached the conventional rectification | straightening member. (A) is a figure which shows the rectification | straightening member concerning this embodiment in a Francis turbine, (b) is a perspective view of the XX cross section in (a) of FIG. In the perspective view of the XX section in Drawing 3 (a), it is a figure showing fixing the straightening member formed with the linear member. It is a figure which shows the example which applied the rectification | straightening member concerning this invention to the Francis pump turbine. It is a figure which shows the example which applied the rectification | straightening member concerning this invention to a mixed flow turbine. It is a figure which shows the example which applied the baffle member concerning this invention to the Kaplan turbine.

Explanation of symbols

1 Francis turbine (hydraulic machinery)
DESCRIPTION OF SYMBOLS 2 Rotating body 3 Casing 3a Flow path 4 Staying 4a Upper plate 4b Lower plate 4c, 5d Water conduit 7 Guide vane 8 Stay vane 9 Rectification member 11 Support member

Claims (3)

A parallel plate type staying in which an upper plate and a lower plate having a circular outer periphery are arranged in parallel, and water flows between the upper plate and the lower plate to form a water conduit,
Around the staying is formed a spiral flow path in which water flows in the circumferential direction, and the staying is fixed so that the outer peripheral edges of the upper plate and the lower plate protrude into the flow path, and A casing that opens between the outer peripheral edges of the upper plate and the lower plate protruding into the flow path, and communicates the flow path and the water conduit;
A rectifying member that rectifies the flow of water flowing into the water conduit from the flow path, and a hydraulic machine that rotates a rotating body by the water flow,
The rectifying member is fixed to a support member that is fixed to the outer peripheral edge of the staying protruding into the flow path, and the rectifying member and the support member are not connected to the casing and are connected to the outer peripheral edge of the staying. A hydraulic machine characterized by being held.   The hydraulic machine according to claim 1, wherein the rectifying member is provided on an entire periphery or a part of an outer peripheral edge of the staying.   The hydraulic machine according to claim 1, wherein the rectifying member is provided on both or either of the upper plate and the lower plate.

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