JP2012127260A - Runner for hydraulic machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily apply coating by injection, etc. to a narrowed part in the inner diameter of a runner or to a blade entry, and also easily apply coating to the whole blade surface.SOLUTION: The runner for a hydraulic machine composed of an outside runner 1, a middle runner 2 and an inner runner 3, includes: fastening members 7, 8 for fastening the outer runner 1 and the middle runner 2 in a separable manner; and fastening members 9, 10 for fastening the middle runner 2 and the inner runner 3 in a separable manner.

Description

  The present invention relates to a runner used in a hydraulic machine such as a water turbine, and more particularly to a runner that is easy to process and maintain.

  In general, a relatively large number of so-called Francis type turbines are used as the hydraulic machine 1 used in the hydroelectric power generation facility. As shown in FIG. 6, the Francis type water turbine mainly includes a spiral casing 32, a runner 33, a crown 35, a runner band 36, blades 37 and 38, a guide vane 39, a speed ring 40, a stay vane 42, a suction pipe (draft). Tube) 44 and a main shaft 46. The runner 33 is connected to a generator (not shown) via the main shaft 46, while water from the upper pond (not shown) is guided to the spiral casing 32, and further, the runner 33 is arranged on the inner peripheral side of the spiral casing 32. In the process of passing through the annular speed ring 40, the stay vane 42 and the guide vane 39, the angular motion is given while increasing the speed and flows into the runner 33 to rotate the runner 33. The rotational movement of the runner 33 rotates the generator via the main shaft 46 to generate electricity. On the other hand, the water that has rotated the runner 33 flows out from the outlet side (inner peripheral side), and flows through the suction pipe 44 to the downstream basin (not shown).

  By the way, since hydraulic machines, such as a water turbine, use river water containing solids, such as earth and sand, as a working fluid, they are easy to be damaged by earth and sand wear in a runner part. In particular, in a runner shape such as a Francis type turbine, damage to the blade inlet portion where flowing water flows into the runner and the blade outlet portion where the thickness of the blade is thin and is greatly affected by wear becomes a serious problem.

  As countermeasures against damage due to such earth and sand wear, conventionally, countermeasures against earth and sand wear by coating such as painting, welding, and thermal spraying have been applied to the blade surface. In recent years, a coating technique by flame spraying (HVOF: High Velocity Oxygen Fuel) has been developed, and it is known that a high-hardness material such as tungsten carbide (WC) material is effective for earth and sand wear resistance.

  However, when performing flame spraying (hereinafter referred to as “thermal spraying”), in the case of a runner such as a Francis turbine, the narrow part and blades on the inner diameter side (blade outlet side) where the earth and sand wear is significant due to restrictions on the dimensions of the equipment. Since it is difficult to construct the entrance portion, a method of welding and assembling the crown, band, and blade after applying thermal spraying to each member has been proposed (Patent Document 1).

JP-A-8-193568

In the above-described coating method by spraying on the conventional runner, welding assembly is performed after coating. However, since the base material and the coating material are different materials and have different coefficients of thermal expansion, cracking and peeling of the coating material may occur at high temperatures. There is a problem that an annealing process for removing necessary stress cannot be performed because of the danger to occur.
Moreover, the coating damage part which generate | occur | produced after starting long-term operation had problems, such as being unable to re-repair by thermal spray coating.

  The present invention has been made to solve the above-described problems, and can easily apply coating by spraying or the like to the narrow portion on the inner diameter side of the runner or the blade inlet portion, and can easily coat the entire blade surface. It is an object of the present invention to provide a runner for a hydraulic machine that can be applied to the machine and that does not require welding of each member after spraying.

  It is another object of the present invention to provide a hydraulic machine runner that can easily repair the coating part by dividing the inner diameter side and the outer diameter side for repairing the damaged part of the coating after starting long-term operation. And

  In order to solve the above-described problem, a hydraulic machine runner according to the present invention is a hydraulic machine runner including an outer runner, an intermediate runner, and an inner runner, and is fastened to be separably fastened to the outer runner and the intermediate runner. A member and a fastening member for fastening the intermediate runner and the inner runner in a separable manner are provided.

  According to the present invention, coating by spraying or the like can be easily applied to the narrow part on the inner diameter side of the runner or the blade inlet, and coating on the entire blade surface can be easily performed, and each after spraying It is possible to eliminate the need for welding the members. In addition, for repairing a damaged part of the coating after the start of long-term operation, the repair of the coating can be easily performed by using the runner as a split structure.

The lineblock diagram of the runner concerning a 1st embodiment. (A) is a block diagram of the runner which concerns on 2nd Embodiment, (b) is AA sectional drawing. (A) is a block diagram of the runner which concerns on 3rd Embodiment, (b) is BB sectional drawing. (A) is a block diagram of the runner which concerns on 4th Embodiment, (b) is CC sectional drawing. The top view of the runner concerning a 5th embodiment The whole runner block diagram.

Embodiments of a hydraulic machine runner according to the present invention will be described below with reference to the drawings.
[First Embodiment]
The runner according to the first embodiment will be described with reference to FIG.
(Constitution)
The runner according to the first embodiment includes an outer runner 1, an intermediate runner 2, and an inner runner 3. The outer runner 1 and the intermediate runner 2 are detachably fastened by fastening members 7 and 8 such as bolts via fastening holders 4 and 5. The intermediate runner 2 and the inner runner 3 are fastened to each other by fastening members 9 and 10 such as bolts.

  By adopting such a fastening structure, a structure equivalent to a conventional runner and a hydraulic performance equivalent to those of a conventional runner are realized. The runner integrated with these fastening structures is fastened to a main shaft 12 of a water turbine by a runner fastening member 11 made of bolts or the like, and the main shaft 12 is directly connected to a generator or a generator motor not shown.

  The outer runner 1 includes an outer runner blade 1a, an outer runner crown 1b integrated with the outer runner blade 1a, and an outer runner band 1c. The intermediate runner 2 comprises an intermediate runner blade 2a and an intermediate runner crown 2b and an intermediate runner band 2c integrated with the intermediate runner blade 2a, and the inner runner 3 is integrated with the inner runner blade 3a and the inner portion thereof by welding. The runner crown 3b and the inner runner band 3c are used. A positioning member 13 such as a knock pin is inserted between the intermediate runner 2 and the inner runner 3.

(Function)
In the first embodiment configured as described above, the outer runner 1 and the inner runner 3 are separable from the intermediate runner 2, and are fitted by a step provided on the positioning member 13 and the holder 5 during reassembly. The state at the time of assembly can be easily reproduced by the action of.

  In addition, by dividing the runner into three parts inside and outside, it is possible to apply coating from both sides to the narrow part on the inner diameter side where the blade width is short, and the workability is also improved because there is no inner diameter side part on the outer diameter side. improves. Thereby, the coating of the blades, the crown, and the entire band portion can be easily performed.

  In addition, since the coating operation such as thermal spraying on the narrow portion on the blade inner diameter side can be performed after welding assembly and stress relief annealing, the wear resistance of the runner can be improved while maintaining the material strength of the conventional runner.

  Furthermore, when repairing damaged parts of the coating, the outer runner 1 and the inner runner 3 with significant earth and sand wear can be disassembled so that the coating can be easily repaired by thermal spraying. Thus, the initial assembly state can be easily reproduced, so that the original runner structure and the hydraulic performance can be reliably and easily restored.

(effect)
As described above, according to the first embodiment, the outer runner and the inner runner can be easily separated and reassembled, thereby improving the workability of the coating operation by thermal spraying and the like, and improving the material strength of the runner. While being held, the wear resistance can be improved. In addition, the damaged portion of the coating can be easily repaired by disassembling the outer runner and the inner runner.

[Second Embodiment]
A runner according to the second embodiment will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the structure same as 1st Embodiment, and the overlapping description is abbreviate | omitted.

  The runner of the hydraulic machine according to the second embodiment is provided with the fastening member insertion holes 14 and 15 in the outer runner 1, and the intermediate runner 2 by the fastening members 7 and 8 such as bolts inserted into the insertion holes 14 and 15. And the outer runner 1 are joined.

  As a result, similar to the first embodiment, coating by thermal spraying or the like can be easily applied to the narrow portion on the inner diameter side or the blade inlet portion, and coating on the entire blade surface can be easily performed. In addition, for repairing a damaged part of the coating, it is possible to easily repair the coating by using a split runner structure.

[Third Embodiment]
A runner according to a third embodiment will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the structure same as said embodiment, and the overlapping description is abbreviate | omitted.

  The runner of the hydraulic machine according to the third embodiment has deformation preventing members 16 and 17 made of knock pins or the like at the joints between the blades of the outer runner 1, the intermediate runner 2 and the inner runner 3. One or more are inserted.

  As a result, it is possible to suppress the deformation due to the water pressure of the blade joint in the water turbine operation state, and it is possible to perform a stable operation without lowering the efficiency even during a large flow operation with a large load on the blade.

[Fourth Embodiment]
A runner according to the fourth embodiment will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the structure same as said embodiment, and the overlapping description is abbreviate | omitted.

  In the runner according to the fourth embodiment, the joints between the blades of the outer runner 1, the intermediate runner 2, and the inner runner 3 are stepped as shown in FIG. It is configured.

  Thereby, similarly to the third embodiment, it is possible to suppress deformation due to the water pressure of the blade joint in the water turbine operation state, and stable operation can be performed without a decrease in efficiency even during large flow operation with a large blade load. It becomes possible.

[Fifth Embodiment]
A runner according to a fifth embodiment will be described with reference to FIG. In addition, the same code | symbol is attached | subjected to the structure same as said embodiment, and the overlapping description is abbreviate | omitted.

The runner according to the fifth embodiment has a structure in which the runner is divided into a plurality of portions in the circumferential direction and the flange portions 18 to 21 of the divided runners are fastened by bolts or the like (not shown).
Thereby, the size of each divided runner becomes small, and it becomes possible to put in a DLC (diamond-like carbon) coating furnace whose hardness is much higher than that of river sediment. Therefore, by applying DLC to the runner component, it is possible to realize a runner structure that does not permanently wear earth without repair.
In the present embodiment, the runner is divided into four parts. However, the present invention is not limited to this, and can be divided into an arbitrary number.

  As mentioned above, although several embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, combinations, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 1 ... Outer runner, 1a ... Outer runner blade, 1b ... Outer runner crown, 1c ... Outer runner band, 2 ... Intermediate runner, 2a ... Intermediate runner blade, 2b ... Intermediate runner crown, 2c ... Intermediate runner band, 3 ... Inner runner DESCRIPTION OF SYMBOLS 3a ... Inner runner blade | wing, 3b ... Inner runner crown, 3c ... Inner runner band, 4, 5 ... Fastening holder, 7, 8, 9, 10 ... Fastening member, 11 ... Runner fastening member, 12 ... Turbine spindle, 13 ... Positioning member, 14, 15 ... Fastening member, 16, 17 ... Deformation preventing member, 18, 19, 20, 21 ... Flange.

Claims (7)

  A hydraulic machine runner comprising an outer runner, an intermediate runner, and an inner runner, the fastening member fastening the outer runner and the intermediate runner in a separable manner, and the fastening member fastening the intermediate runner and the inner runner in a separable manner A hydraulic machine runner characterized by comprising:   The hydraulic machine runner according to claim 1, wherein a fastening member that detachably fastens the outer runner and the intermediate runner is fastened to the outer runner and the intermediate runner via a fastening holder.   The hydraulic machine runner according to claim 1, wherein an insertion hole for a fastening member is provided in the outer runner, and the outer runner and the intermediate runner are detachably fastened by a fastening member inserted into the insertion hole.   The runner of a hydraulic machine according to any one of claims 1 to 3, wherein a positioning member is provided at a joint portion of each runner blade of the outer runner, the intermediate runner, and the inner runner.   The hydraulic machine runner according to claim 4, wherein the positioning member is a pin connecting the runner blades.   The hydraulic machine runner according to any one of claims 1 to 3, wherein a joint portion of each runner blade of the outer runner, the intermediate runner, and the inner runner has a step structure.   The runner for a hydraulic machine according to any one of claims 1 to 6, wherein the runner is divided into a plurality of pieces in the circumferential direction.

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