JP2002310053A - Runner of water turbine, manufacturing method for it, and water turbine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a runner of a water turbine, manufacturing method for it and a water turbine, capable of facilitating manufacture of the runner of the water turbine, heightening the assembling accuracy and restraining the manufacturing cost. SOLUTION: The runner 3 is divided by the number of vanes 4 constituting the runner 3 to manufacture a runner piece 5 formed by one vane 4 and a crown part 5a and a band part 5b attached thereto as fixing parts. A required number of the runner pieces 5 for the runner 3 are molded by casting and machined. The respective machined runner pieces 5 are combined for the total number of vanes and joined by welding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a runner of a water turbine that generates electric power by using fluid energy of water, a method of manufacturing the runner, and a water turbine.

[0002]

2. Description of the Related Art A general configuration of a water turbine will be described with reference to FIG. The running water guided from the hydraulic pipe to the water wheel 1 enters the spiral casing 2, flows through the guide vanes 6 for guiding, and is guided to the runner 3 as an impeller. The running water that has entered the runner 3 generates hydraulic power while flowing through the vanes 4 provided on the runner 3, and rotates the runner 3 about the main shaft 7. The running water that has been rotated and that has been sent out below the main shaft of the runner 3 passes through the suction pipe 8 and is discharged to the outlet. The main shaft 7 that rotates in conjunction with the runner 3 rotates a generator (not shown) provided above the main shaft 7 to generate energy such as electric power.

The runner 3 comprises a vane 4 and a crown 3a and a band 3b for supporting the vane 4. Each vane 4 molded by casting is machined and then welded to the crown 3a and the band 3b. The runner 3 of the water turbine manufactured by this manufacturing method is generally called a welding runner. Further, there is an integrated structure runner in which the vane 4 is cast-molded into the crown 3a or the band 3b so as to have an integral structure, and each part is machined and formed by a grinder and then joined.

[0004] Further, Japanese Patent Laid-Open Publication No.
According to the Francis turbine runner processing method of No. 60, a method is described in which the crown surface and the band surface are molded by casting so that every other vane is provided on each of the crown surface and the band surface. By attaching vanes every other sheet, a gap between the vanes can be obtained, a cutter of a machine tool for machining can easily enter, and a continuous cutting operation can be performed.

[0005]

In the conventional method for manufacturing and processing a runner of a water turbine, the crown, the band and the vane forming the runner are formed by casting, respectively. Large water turbines with large effective heads or flow rates also have large runners, which result in large molds, which makes molding by casting difficult. Further, when machining a large runner, it may be necessary to move the machine tool or the runner, which significantly reduces workability. Further, it is difficult to join the vane to the crown and the band, which are the fixing portions, by welding in a runner having a large number of vanes. This is because the provision of a large number of vanes narrows the gap between the vanes and hinders automatic welding by a machine. If the vane length is long,
Further, the difficulty of welding comes to the surface. Moreover, since each vane is individually welded to the crown and the band, it is difficult to secure the mounting accuracy.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and facilitates the manufacture of a runner of a water turbine, increases the accuracy of assembling the runner, further reduces the manufacturing cost, a method of manufacturing the water turbine, and a water turbine. The purpose is to provide.

[0007]

According to the first aspect of the present invention,
A runner for a water turbine, comprising: a vane; and a fixing portion for fixing the vane in an upright state. The fluid energy of water flowing from a spiral spiral casing that guides water introduced from a hydraulic pipe is converted into rotational energy. In the water turbine runner, the runner pieces obtained by dividing the runner according to the number of vanes used for the runner are joined to each other.

According to such a water turbine runner, a water turbine runner is manufactured by using runner pieces of a size divided according to the number of vanes. The term “fixing portion” as used herein refers to a crown portion that forms part of a crown, a band portion that forms part of a band, or both. The fixing part described below refers to the fixing part.

According to a second aspect of the present invention, there is provided a method of manufacturing a runner of a water turbine, comprising a vane and a fixing portion for fixing the vane in an upright state, and having a spiral shape for guiding water introduced from a hydraulic pipe. In a method of manufacturing a runner for a water turbine, which converts fluid energy of water introduced from a spiral casing into rotational energy, runner pieces in which the runner is divided according to the number of vanes used for the runner are manufactured, and these are used for welding. It is characterized by joining.

According to the method for manufacturing a runner of a water turbine, each runner piece obtained by dividing the runner by the total number of vanes is manufactured. It is ideal that the runner piece has a divided shape determined in accordance with the shape of the vane, and that the fixed portions of the vane are cast into the same shape as the number of vanes by casting. However, when the shape is complicated or the shape of a part is different, it is not necessary to manufacture a runner piece of the same shape. It is desirable to lead to ease of machining. When machining is required, each runner piece is individually performed, and it is preferable that the processed portion and the processed amount are made constant by manufacturing the runner pieces into the same shape.

According to a third aspect of the present invention, there is provided a method for manufacturing a runner of a water turbine according to the second aspect, wherein the runner piece comprises:
A single vane and a separate fixed portion attached thereto are formed.These runner pieces are molded by casting for the number of vanes required for the runner, and after machining the runner pieces, the runner pieces are welded. It is characterized by joining.

According to such a method of manufacturing a runner for a water turbine, each runner piece has a mass and a size divided by the total number of vanes of the runner, and the degree of freedom increases in a manufacturing process by casting. In each runner piece molded for each vane by casting, there is no gap between the vanes. This is because the runner piece is constituted by one vane, and there is no adjacent vane.
Therefore, there is no processing obstacle that the cutter of the machine tool is difficult to insert. Further, it is ideal to facilitate machining by forming runner pieces of the same shape. Also, since each runner piece is integral with the vane, there is no need to weld the vane to the crown and band. This will easily lead to a shape that matches the design dimensions. When joining each runner piece by welding and assembling it into a runner, the welding line becomes a straight line or a constant curve, and in the case of runner pieces of the same shape, the welding line is repeated.

According to a fourth aspect of the present invention, there is provided a method of manufacturing a runner for a water turbine according to the second aspect, wherein the runner piece comprises:
Two or more vanes and associated fixed portions are formed.The runner pieces are molded by casting in a quantity that satisfies the number of vanes required for the runner, and the runner pieces are machined. It is characterized in that the pieces are joined by welding.

According to such a method for manufacturing a runner for a water turbine, molding a runner piece by using two or more vanes and a fixing portion associated therewith reduces welding lines when assembling the runner. When a runner is formed using such a runner piece, the number of vanes used for the runner is small, which is effective when there is a gap for machining between the vanes.

According to a fifth aspect of the present invention, there is provided a water turbine having a runner of a water turbine, wherein a spiral spiral casing for guiding water introduced from a hydraulic pressure pipe, and a fluid energy of the water flowing from the spiral casing are provided. In a water turbine provided with a water turbine runner for converting into rotary energy, the water turbine runner is a water turbine runner according to claim 1.

According to such a water turbine, a water turbine incorporating the runner of the water turbine having the above characteristics can be constructed.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described below with reference to FIGS. 1, 2 and 3. FIG.

FIG. 1 shows a general structure of a water turbine. The water wheel 1 includes a spiral casing 2 for guiding flowing water, a guide vane 6 for controlling the flowing water, a runner 3 rotated by the flowing water, a suction pipe 8 for discharging the flowing water passing through the runner 3, and a rotating shaft of the runner. And a main shaft 7 provided in the main body. The runner 3 includes a vane 4 for guiding flowing water, and a crown 3a and a band 3b, which are fixing portions for standing and fixing the vane.

The running water guided from the hydraulic pipe to the water turbine 1 enters the spiral casing 2 and while flowing, the flow is regulated and the flow is adjusted by guide vanes 6 for guiding. The rectified running water flows from the tip of the vane 4 constituting the runner 3 to the runner 3.
To generate hydraulic power while flowing through the vane 4,
The runner 3 is rotated about the main shaft 7. The runner 3 includes a vane 4 and a crown 3 which is a fixing portion that stands and supports the vane 4.
a and a band 3b. The main shaft 7 is provided at the center of the runner 3 and serves as a rotation axis of the runner 3. In addition, a generator (not shown) is provided on the upper portion of the main shaft 7, and the generator is configured to generate power when the main shaft 7 rotates. Rotate runner 3 and move vane 4
The running water sent downward by the main shaft of the runner 3 is discharged to the outlet through the suction pipe 8.

FIG. 2 is a view of the runner 3 of the water turbine provided at the position shown in FIG. 1 as viewed from the crown 3a side.
The runner 3 shown in FIG. 2 is composed of a runner piece 5 divided by the total number of vanes 4, and a crown-side welding surface 9.
And the band side welding surface 10 and are joined by welding.

As shown in FIG.
The number of the vanes 4 is 1.
It is formed from seven runner pieces 5. In each of the runner pieces 5, the crown 3a and the band 3b are divided by a crown side welding surface 9 and a band side welding surface 10, respectively. Each of these welding surfaces is determined in consideration of the shape of each of the vanes 4, and the crown 3 a and the band 3 b are respectively connected to the crown portion 5 constituting the runner piece 5.
a and the band portion 5b.

FIG. 3 schematically shows one of the runner pieces 5 in FIG. Reference numeral 5a denotes a crown portion 5a (fixed portion) obtained by dividing the crown 3a shown in FIG.
It is. Reference numeral 5b denotes a band portion 5b (fixed portion) obtained by dividing the band 3b shown in FIG. Reference numeral 4 denotes one vane.

Each of the vanes 4 has a three-dimensional shape in order to efficiently guide flowing water and generate hydraulic power. The crown portion 5a and the band portion 5b are integrally provided at both upper and lower ends of each of the vanes 4. Each of the runner pieces 5 is welded and joined at the crown-side welding surface 9 and the band-side welding surface 10 which are joint surfaces, and the runner 3 is formed.

Next, a method of manufacturing a runner of a water turbine will be described in detail. Each of the runner pieces 5 shown in FIG. 3 is formed by casting using a mold. Each runner piece 5
The crown 3a and the band 3b constituting the runner 3 are provided with the crown portion 5a and the band portion 5b obtained by dividing the crown 3a and the band 3b by the total number of the vanes 4, and are integrated with one of the vanes 4. I have. The divided portion is divided along the crown side welding surface 9 as shown in FIG. 2 in the crown portion 5a. In the band portion 5b, the band-side welding surface 1 shown in FIG.
It is divided along zero. Since each of the runner pieces 5 is manufactured by the total number of the vanes 4 constituting the runner 3, the same mold can be used by forming the same shape. This means that the runner piece 5
In addition to being able to manufacture with a small-scale casting facility, the molding can be facilitated and the cost of the mold can be reduced. Conventionally, since the vane 4 shown in FIG. 1 is welded to the crown 3a and the band 3b by welding, it is difficult to work in a narrow space and to maintain accuracy. However, the present invention has been solved by integrating the vanes 4 as described above.

Each of the runner pieces 5 formed by casting
Are machined to design dimensions. In the machining, the runner pieces 5 having the same shape are cut into the same shape, and the total number of the vanes 4 is repeatedly machined. The machining of each runner piece 5 eliminates a gap between the vanes 4, so that a cutter of a machine tool can be easily inserted into a cutting portion. Further, since the respective runner pieces 5 have the same shape, the same machining is performed for the total number of the vanes 4. Therefore, automation of machining can be easily achieved, and the production accuracy can be improved. Further, in one example of the present invention, the respective runner pieces 5 have been described as having the same shape, but the shape of the runner 3 may be complicated,
Alternatively, in a situation where the shape of a part is changed, it is not necessary to make the shape the same.

After the respective runner pieces 5 shown in FIG. 3 are manufactured for the total number of the vanes 4, the respective runner pieces 5 are combined into a substantially circular shape like the runner 3 shown in FIG. More specifically, the crown portion 5a is welded to the crown side welding surface 9 so as to form the crown 3a. Further, the band portion 5b is welded to the band side welding surface 10 so as to form the band 3b. As described above, since each of the welding surfaces is welded and joined, it is desirable that each of the runner pieces 5 is manufactured so as to provide a groove for welding in advance. As shown in FIG. 2, when the runner 3 is formed using the runner pieces 5 having the same shape, the welding line becomes a constant curve or straight line and is repeatedly performed, so that the welding can be easily automated. It can be aimed at.

The runner 3 in which the runner pieces are combined by welding is used to finish a welded portion, and FIG.
Is mounted on the water wheel 1 as shown in FIG. The runner 3 of the water turbine 1 can be used in a pump water turbine having a pumping function.

Water turbine 1 manufactured by the above-described manufacturing method
Is an example in which one runner piece 5 is manufactured for one vane 4 and the runner 3 is manufactured. However, when the number of vanes 4 constituting the runner 3 is small, or when there is a gap between the vane 4 and the adjacent vane 4, machining may be performed without any problem. In this case, the runner 3 can be manufactured using a runner piece 5 having two or more vanes 4.

Some of the runners 3 of the water turbine 1 do not have the band 3b as a fixed portion. However, it is also applicable to manufacture the runner 3 using the runner piece 5 even when there is no band 3b.

[0030]

As described above, according to the water turbine runner, the method of manufacturing the same, and the water turbine according to the present invention, the following effects can be obtained. According to the first aspect of the present invention, a runner piece is manufactured and combined to form a runner, so that a light-weight runner piece can be manufactured with a small-scale facility without using a large-scale facility. And eliminate welding work on the vane,
This makes it possible to provide a water turbine runner with reduced manufacturing costs.

According to the second aspect of the present invention, the runner pieces are manufactured and joined by welding to form the runner, so that the runner can be reduced in weight with a small facility without using a large facility. Pieces can be manufactured, and a runner for a water turbine can be manufactured with reduced manufacturing costs by eliminating welding work to the vanes.

According to the third aspect of the present invention, a runner piece for each vane is formed by casting, machined after molding, and then a runner is formed by welding. Processing can be performed, and the mounting position of the vane becomes the same, so that manufacturing accuracy can be increased. Further, the size of the mold can be reduced, and the production cost by casting can be suppressed. Further, the cutter of the machine tool can be easily guided to the cutting surface, and the difficult machining problem can be solved. Further, the welding line can be a straight line or a curved line on the surface of the runner, so that the welding can be automated and the manufacturing cost can be reduced.

According to the fourth aspect of the present invention, the number of runner pieces is reduced by casting two or more runner pieces for each vane, forming the runner pieces, and then forming the runners by welding. It is possible to reduce the number of welding lines when combining runners. Therefore, manufacturing costs can be reduced.

According to the fifth aspect of the present invention, a runner of a water turbine can be manufactured with high precision as described above by using the runner formed by the runner pieces, and automation in manufacturing is promoted. Is done. Therefore, it is possible to guide the performance of the turbine as planned, to facilitate the production, and to provide a water turbine with a runner of the water turbine with reduced production cost.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a water turbine according to the present invention.

FIG. 2 is a partial sectional view showing an example of a runner of the water turbine according to the present invention.

FIG. 3 is a perspective view showing an example of a shape of a runner piece according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water wheel 2 Spiral casing 3 Runner 3a Crown 3b Band 4 Vane 5 Runner piece 5a Crown part 5b Band part 6 Guide vane 7 Main shaft 8 Suction pipe 9 Crown side welding surface 10 Band side welding surface

Continuation of the front page F term (reference) 3H072 AA07 AA27 BB03 CC02 CC49

Claims (5)

[Claims] 1. A vane and a fixing portion for fixing the vane in an upright state, and convert fluid energy of water flowing from a spiral spiral casing for guiding water introduced from a hydraulic pipe into rotational energy. A runner for a water turbine, wherein runner pieces obtained by dividing the runner according to the number of vanes used for the runner are joined to each other. 2. A vane and a fixing portion for fixing the vane in an upright state, and convert fluid energy of water flowing from a spiral casing to guide water introduced from a hydraulic pipe into rotational energy. A method for producing a runner for a water turbine, comprising: producing runner pieces in which the runner is divided according to the number of vanes used for the runner; and joining these pieces by welding. 3. The runner piece is a single vane and a divided fixed portion attached to the vane. The runner pieces are molded by casting the number of vanes required for the runner, and the runner pieces are machined. 3. The method for producing a runner for a water turbine according to claim 2, wherein the runner pieces are joined by welding after processing. 4. The runner pieces are two or more vanes and divided fixed portions attached to the runner pieces. The runner pieces are molded by casting in a quantity that satisfies the number of vanes required for the runner. 3. The method according to claim 2, wherein the runner pieces are joined by welding after machining the runner pieces. 5. A water turbine comprising: a spiral casing for guiding water introduced from a hydraulic pipe; and a runner of a turbine for converting fluid energy of water introduced from the spiral casing into rotational energy. A water turbine characterized in that the runner is a runner of the water turbine according to claim 1.