JPH02196167A - Leak wastewater treatment system for hydraulic machinery and usage thereof - Google Patents

Abstract

PURPOSE:To make it possible to perform the stable operation of hydraulic machinery continuously by forming an outlet end of a leak wastewater treatment system, extracting a leakage of water, out of a guide vane, collected in a runner chamber and delivering it to a draft pipe, into two-way ports different in height of each setting position. CONSTITUTION:In a vertical shaft spiral type turbine, each runner side pressure chamber 7 is formed at both sides of a runner 2 being directly connected to a turning shaft 3, and it serves as a socket leading a leakage of water out of a closed guide vane 4. In this case, a leak drainage system 6a connecting the runner side pressure chamber 7 and a vertical part of a draft pipe 5 is constituted of a leak drain pipe 12, opening an inlet end to the runner side pressure chamber 7 while provided with an outlet end with two-way ports 14a, 14b varying each height position. One side of these two-way ports 14a, 14b is opened in a range of L1<0.9XDe when an outlet diameter of the runner 2 is set to De and a distance L1 from an outlet of the runner 2 to L1, respectively, and the other is opened in a range of L2<0.95XDe when a distance from a cross section external line H of the draft pipe 5 is set to L2.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) This invention provides that when water leaks from a closed guide vane during idling operation of a runner, if left unattended, the frictional heat caused by the rotation of the runner will be released. In view of the fact that water is imparted to leakage water, wasting rotational energy, deteriorating flow characteristics, and further causing wear and tear on component equipment, 1 wastewater treatment device for hydraulic machinery that preferably extracts leakage water and Regarding usage.

(Prior Art) In hydraulic machines, especially pumps or pump-turbines, water filled in the runner is forcibly pushed down into the suction pipe during start-up operation or phase adjustment operation in order to stabilize the power system.
A so-called runner idle operation is being carried out.

To operate this runner, with the guide vane (movable guide vane for flow rate adjustment) located on the inlet side of the runner closed, high-pressure air is sent to the water in the runner chamber to push it down, and the water reaches the suction pipe. At the bottom, the runner is rotated in a gas phase, and this operation is a so-called pre-rating pre-rating operation in which the drive torque of the rotating shaft is not wasted and the rated operation is started.

During such preparatory operations, some of the operating water may leak into the runner chamber through the gaps between the guide vanes. If there is water leakage in the runner room,
Under the direct influence of the centrifugal force caused by the rotation of the runner, the leakage water gathers around the guide vanes, creating a kind of barrier by forming a dense film of water behind the guide vanes.

The barrier directly receives the frictional heat generated during the rotation of the runner and enters a heated state, which causes undesirable phenomena that induce expansion and deformation of the component equipment.

As a measure to eliminate such phenomena, for example,
(As seen in Japanese Patent Publication No. 2002, Japanese Patent Publication No. 47-38339, and Japanese Patent Application Laid-open No. 52-74736, many techniques have been disclosed for removing water leakage from guide vanes using a single drain pipe. The technique for extracting the target will now be explained in more detail using Figure 3.

This technology uses a spindle spiral water turbine as an example.
In the figure, a runner 2 directly connected to a rotating shaft 3 is arranged in the center of a spiral casing 1, and an annular row of guide vanes 4 that can be opened and closed are arranged on the inlet side of the runner 2, and an elbow-shaped guide vane 4 is arranged on the outlet side of the runner 2. A suction pipe (draft tube) 5 is arranged so as to extend to a lower pond (not shown).

The runner 2 is covered with covers on the top and bottom to form a runner side pressure chamber 7. The runner side pressure chamber 7 is equipped with a leakage treatment device 6a for removing water leakage from the guide vane 4. The 1 wastewater treatment device 6a includes a pair of 1 wastewater pipes 8a.

8b, one inlet end of which is opened in the runner side pressure chamber 7, and the other inlet end opened directly below the guide vane 4. The first drain pipes 8a and 8b extend along the suction pipe 5, and connect their respective outlet ends to the vertical line portion of the suction pipe 5 with a first valve 9as and a second valve 9b interposed therebetween.

In this configuration, when the water turbine is operated at its rated capacity, the flow rate of the working water from the spiral casing 1 is adjusted by the guide vanes 4, and the adjusted working water gives rotational energy to the runner 2, which is used to generate electricity (not shown). The machine outputs electricity, and the working water that has completed its work is sent out from the runner 2 through the suction pipe 5 to the lower pond. In addition, when starting up the water turbine or during phase adjustment operation, the working water from the spiral casing 1 is cut off by the guide vane 4, and the filled water level 11 is pushed down to the position shown in the figure, leaving the runner chamber IO empty. The runner is idled, and during this period, water leaking from the guide vane 4 is extracted using the first drain pipes 8a and 8b and sent to the suction pipe 5. In this way, leakage water is actively extracted and damage to the components that is expected to occur while the runner is idling is prevented and maintained.

(Issue to be Solved by the Invention) By the way, in the heated drainage device having the above configuration, 1 drainage pipe 8a,
Since the outlet end of 8b is connected to the vertical line part of the suction pipe 5 at a relatively upper position, the leaked water is heated by the frictional heat while the runner is idling, and the heated water is drawn out to the suction pipe 5. Due to the fact that the runner 2 is being sent out, the heated water is drawn in during the runner rotation, causing an excessive temperature rise in the runner 2 itself.

This phenomenon is particularly noticeable when the runner is idling for a relatively long period of time, such as during phase adjustment operation, and a solution to this phenomenon is required.

As one of such solutions, it is considered that the entrainment of heated water can be prevented by making the first drain pipes 8a and 8b into extension pipes 8e and 8d extending to the position shown by the broken line in the third figure.

However, extending the first drain pipe 8aJb to the broken line position causes the heated water to drag the gas phase (high-pressure air) in the runner chamber IO into the lower pond, causing the pressure in the runner chamber 10 to decrease over time. As a result, the pressure at the water surface 11 increases and eventually the runner 2 comes in contact with the water surface, making it impossible to continue the runner idling operation, or else the pressure is constantly high in order to continue the runner idling operation. Air must be added to the runner chamber 10, leading to an increase in the size of support equipment such as a compressor.

The above problems will be quantitatively explained with reference to FIGS. 4A and 4B and 5A and 5B. Figures 4A and 4B show the correspondence between the horizontal axis coordinates of the graph and the actual dimension length using the same symbols. The distance from the exit of No. 2 is ML1, and the runner exit diameter is ML1. shall be.

When the distance L1 is changed, the runner chamber l when the runner is idling
The temperature increase value Δt of O changes as shown in FIG. 4A. The solid line in this graph shows the temperature rise value when the runner is idling in the power generation direction, and the broken line shows the temperature rise value when the runner is idling in the pumping direction. Note that the temperature increase value Δt indicates the saturated value of the temperature increase from the start of the runner idle operation.

This graph shows that the temperature rise value △t is significantly different between runner idling operation in the power generation direction and runner idling operation in the pumping direction, and in the former case, the temperature rise is particularly severe; If the runner is idling, L1
It is shown that /Do changes rapidly after reaching 0.9.

In Figures 5A and 5B, the abscissa of the graph corresponds to the actual size length using the same symbol. Let the distance be L from line H. Runner room 1 by changing distance #L2
FIG. 5A is a graph of the air leakage ff1Q from 0 (the amount of air leakage here is defined as the air in the runner chamber 10 drawn into the water surface located at the bottom of the suction pipe 5). In this graph, the solid line indicates when the runner is idling in the power generation direction, and the broken line indicates when the runner is idling in the pumping direction.

As can be understood from this graph, the amount of leakage Q becomes higher when the distance ML2 is short, regardless of whether it is in the power generation direction or the pumping direction.
/D o becomes a low value around 0.85.

In this way, when the runner is idling, the position of the outlet end of the drain pipe that extracts leakage water in the suction pipe has an important influence on the operation of hydraulic machinery. desired.

This invention was developed in view of the conventional problem that the connection position of the outlet end of the drain pipe to the suction pipe deteriorates the flow characteristics due to the wear and tear of the component equipment, or leads to the increase in the size of the support equipment. The purpose of this paper is to publicize a wastewater treatment system for hydraulic machinery that allows stable operation to continue without any problems, and its usage method.

[Structure of the invention]

(Means for Solving the Problem) As a first configuration for achieving the above object, the present invention closes the guide vane during startup operation or phase adjustment operation,
In a hydraulic machine that pushes filled water down the suction pipe and rotates the runner while the runner chamber is empty, water leakage from the guide vane is extracted during the runner idle operation.
The inlet end of the drain pipe is opened in the runner side pressure chamber, and the outlet end of the first drain pipe is connected to the suction pipe with two ports at different heights, and the first outlet end has the runner outlet diameter D1. When the distance from the outlet to the one outlet end is Ll, L1/Do<0.9, and the other outlet end has a runner outlet diameter D,
When the vertical distance from the suction pipe-like transverse outline to the other outlet end is L2, the configuration satisfies the following relationships: L2/De<0.95.

The second configuration is used in a hydraulic machine that closes the guide vane during startup operation or phase adjustment operation, pushes down the filled water suction pipe, and rotates the runner while the runner chamber is empty. 1. The inlet end is opened in the same direction, and the outlet end is opened in two directions at different heights and connected to the suction pipe.
The drain pipe is configured to drain leakage water by selectively using both or one of two types of outlet ends of one drain pipe when the pressure in the empty space reaches a predetermined pressure.

Furthermore, the third configuration is that when the runner is idling in the power generation direction of the hydraulic machine, the outlet end farthest from the runner outlet of the two types of outlet ends of one drainage pipe is used to extract leaked water, and the leakage water is extracted in the pumping direction of the hydraulic machine. When the runner is running idle, leakage water is drained using the outlet end of the 2Fli type of one drain pipe that is closer to the runner outlet.

(Function) Therefore, both the temperature rise in the runner room and the amount of air leakage in the runner room can be kept within an allowable range without causing any operational problems. In other words, the increase/decrease in temperature rise and the increase/decrease in air leakage have a contradictory relationship depending on the mounting position of the outlet end of the drain pipe, so if you skillfully use the two types of outlet ends depending on the type of operation, The deadline E t in FIGS. 4A and 5A,
From E2, the value becomes the value on the right, and the hydraulic machine can continue operating without any problems.

(Example) Hereinafter, a waste water treatment device for a hydraulic machine according to the present invention and a method of using the same will be explained with reference to the drawings.

FIG. 1 is a schematic diagram showing an embodiment of the present invention, in which a chamber-shaft spiral water turbine for power generation is applied as an example of the hydraulic machine. Components that are the same as those used in the conventional example shown in FIG. 3 are given the same reference numerals.

The chamber shaft spiral water turbine applied to this embodiment has a rotating shaft 3
A guide vane 4 arranged in an annular row with the runner 2 is housed in the spiral casing 1, and the working water from the spiral casing 1 passes through the guide vane 4 and the runner 2. The hydraulic energy is converted into rotational energy, and the working water after the energy conversion is sent out to a lower pond (not shown) through an elbow-shaped suction pipe 5. In addition, runner side pressure chambers 7 are provided on both sides of the runner 2.
is formed to serve as a socket for guiding water leakage from the closed guide vane 4.

The runner side pressure chamber 7 and the vertical part of the suction pipe 5 have two openings with one position difference! It consists of one drain pipe 12 with 4a and 14b. This one drain pipe 12 is equipped with a first valve 13a and a second valve 13b at two ports 14a and 14b.

One of the two directions 14a and 14b is connected to the runner 2.
Let D be the exit diameter of the runner 2, and let the distance be Ll from the exit of the runner 2, it connects to the vertical part of the suction pipe 5 within a range of Ll<0.9xD8. The other one is connected to the vertical portion of the discharge pipe 5 at a position within the range of L2<0.95XD8, where L2 is the distance from the cross-sectional outline H of the suction pipe 5.

In this way, when water leaks from the guide vane 4, the first valve 13a1 and the second valve 13b are skillfully opened and closed, and the two-way port 14a is opened and closed.
, 14b are used to draw out leakage water.

Next, the method of using the first drain pipe Ga will be described in detail using runner idle operation as an example.

For example, when the rotational direction of the runner 2 is in the power generation direction, if water leaks from the closed guide vane 4, the first valve f3a is closed, the second valve 13b is opened, and the leaked water from the runner side pressure chamber 7 is drawn out and sucked out. Send it to tube 5.

In this case, since one of the two ports 14a and 14b is quite far from the runner 2, it is not affected by heating water leakage from the runner chamber IO. However, removing water leakage 2
Since one of the sides 14a and 14b, 14b, is extremely close to the filled water surface U, there is a concern about air leakage.
2), so it is not an amount that would cause a problem in driving.

On the other hand, when the rotational direction of the runner 2 is in the water pumping direction, if water leaks, the first valve 13a is opened, the second valve 13b is closed, and the leaked water from the runner side pressure chamber 7 is extracted and sent to the discharge pipe 5. In this case, one of the two openings 14a and 14b 14
Since there is a considerable distance between A and the filled water surface 11, the amount of air leakage is not a problem for operation. However, since the two-way port 14a is used for the runner 2, there is concern about the temperature rise in the runner chamber 10. . However, the water leak in this case is the fourth
Since the temperature rise in the runner chamber 10 is a small amount at a position behind the deadline E1 in FIG.

Note that when the rotation direction of the runner 2 is in the power generation direction and there is little water leakage from the guide vane 4, the temperature rise in the runner chamber 10 will not be a problem, so in this case, the first valve 13
It is convenient to open the valve a and close the second valve 131) to reduce leakage. In addition, if the rotational direction of the runner 2 is in the water pumping direction and leakage is not a problem, if the first valve 13a is closed and the second valve 13b is opened, the runner chamber
This is preferable in that it suppresses a temperature rise of 0.

As described above, in the embodiment according to the present invention, by skillfully using one drain pipe with two ports at different mounting positions and heights, it is possible to preferably suppress the temperature rise or air leakage in the runner room, and to constantly Stable runner idle operation can continue.

FIG. 2 is a schematic diagram showing another embodiment of the present invention.
This is an example in which another configuration is added. That is, a second leakage drain pipe 12a is arranged in parallel to the first drain pipe 12 of the first embodiment, a third valve 15b is interposed in the second leakage drain pipe 12a, and its inlet end is connected to the guide vane 4. It is installed directly below the pipe, and its protruding end is connected to the drain pipe 12. In this embodiment, water leakage from the runner side pressure chamber 7 and water leakage accumulated between the runner 2 and the guide vane 4 can be simultaneously drawn out to the suction pipe 5, thereby doubling the drainage capacity of the runner chamber 2 and raising the temperature to -. This is very convenient in terms of suppressing the In this case, the third valve I5 is used in combination with the first valve Hla or the second valve 131) as appropriate.

Although both the first and second embodiments are examples of a single-stage chamber-shaft spiral water turbine, the same effects as described above can be obtained not only in a single-stage example but also in a multi-stage example.

〔Effect of the invention〕

As explained above, in one wastewater treatment device of a hydraulic machine and its usage method according to the present invention, leakage water from a guide vane that accumulates in a runner chamber is extracted and sent to a suction pipe.
The outlet end of the wastewater treatment device has two ports with different installation heights.In this invention, the runner room temperature is 1.
It is possible to solve all the problems of the conventional technology where various problems occurred because the increase and decrease of air leakage were completely opposite to the increase and decrease of air leakage, and this has the effect of enabling stable operation in this type of field.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a hydraulic machine showing an embodiment of the present invention;
Fig. 2 is a schematic diagram of a hydraulic machine showing another embodiment of the present invention, Fig. 3 is a schematic diagram of a hydraulic machine showing a conventional embodiment, and Fig. 4 is a schematic diagram of a hydraulic machine showing a conventional embodiment.
Figure A is a graph showing the temperature rise characteristics of the runner chamber, Figure 4B is a schematic diagram of a hydraulic machine that corresponds to the dimension symbols on the abscissa in Figure 4A, and Figure 5A is the runner chamber drawn into the suction pipe filled with water. FIG. 5B, which is a graph showing gas phase air leakage characteristics, is a schematic diagram of a hydraulic machine in which the dimension symbols on the abscissa in FIG. 5A are made to correspond. 2...Runner, 4...Guide vane, 5
...suction pipe, 6a...1 wastewater treatment device, 7
...Runner side pressure chamber, lO...Runner chamber, 12...
1 drainage pipe, 14a, 14b...2 direction agent
Patent Attorney Noriyuki Ken Yudo Daishimaru Ken Diagram ρ, θS L 2/De Figure 5A Figure 5B

Claims (3)

[Claims] (1) In a hydraulic machine that closes the guide vane during start-up operation or phase adjustment operation, pushes the filled water down the suction pipe, and gives the runner rotational operation with the runner chamber empty.
During runner idle operation, the inlet end of the leakage drain pipe for drawing out leakage water from the guide vane is opened in the runner side pressure chamber, and the outlet end of the leakage drain pipe is connected to the suction pipe at two-way ports at different heights. In addition, the first outlet end has a runner outlet diameter of D
_e, the distance from the runner exit to the first exit end is L_
1, L_1/D_e<0.9, and the other outlet end has a runner outlet diameter of D_e.
A leakage water treatment device for a hydraulic machine, characterized in that the following relationship is satisfied: L_2/D_e<0.95, where L_2 is the distance from the cross-sectional outline of the suction pipe to the other outlet end. (2) In a hydraulic machine that closes the guide vane during start-up operation or phase adjustment operation, pushes the water-filled suction pipe downward, and gives rotational operation to the runner while the runner chamber is empty.
A leakage drain pipe is opened in the runner side pressure chamber with a common inlet end and two outlet ends at different heights and connected to the suction pipe. A method of using a leakage water treatment device for a hydraulic machine, characterized in that both or one of two types of outlet ends are used to draw out leakage water. (3) When the runner is idling in the power generation direction of the hydraulic machine, the outlet end farthest from the runner outlet of the two types of outlet ends of the leakage drain pipe is used to extract leakage water, and when the runner is idling in the pumping direction of the hydraulic machine. 3. The method of using a leakage water treatment device for a hydraulic machine according to claim 2, wherein the leakage water is extracted by using one of the two types of outlet ends of the leakage water pipe that is closer to the runner outlet.