JP5677618B2 - Pressure water level meter and pressure water level meter maintenance method - Google Patents

Description

  The present invention relates to a pressure water level meter and a pressure water level meter maintenance method, and more particularly to a pressure level meter suitable for installation in a water intake dam of a flow-type power plant and a pressure level suitable for maintaining a pressure water level meter from sediment accumulation. It relates to water level meter maintenance methods.

  The flow-type power plant uses many pressure water level meters to control the gate opening and closing by measuring the water level of intake dams and waterways, and the pressure water level meter is an important civil engineering facility in the flow-type power plant. It is.

Such a pressure water level meter includes a water level detection sensor 111 and a cylindrical wave breaker 112, as in the pressure water level meter 110 shown in FIGS. 2 (a) and 2 (b).
Here, since the water level detection sensor 111 is a precision instrument, the water level detection sensor 111 is inserted into the wave breaker 112 and attached to the bottom surface of the wave breaker 112 so as not to be directly affected by flowing water or damage caused by earth and sand. Yes.
The breakwater tube 112 has an outer diameter of about 40 mm, is inserted into the water so that the bottom surface reaches the bottom of the intake dam, and is fixed to the concrete retaining wall 1 of the intake dam with a plurality of bolts B.
Water guide holes 112a are formed on the circumferential surface and bottom surface of the wave breaker 112. Water is introduced into the wave breaker 112 from the water feed holes 112a, and the water level detection sensor 111 detects the pressure from the water surface. The water level is measured (numerical value display).

However, as shown in FIG. 2B due to water discharge, earth and sand accumulate around the wave breaker 112, and when earth and sand flows into the wave breaker 112 from the water guide hole 112a of the wave breaker 112 and accumulates, As a result of poor tracking of the water level inside the wave tube 112, a water level measurement error by the water level detection sensor 111 becomes large, causing malfunction of an automatic control device that performs gate opening / closing control of the intake dam.
In order to remove the sediment accumulated in the breakwater pipe 112, the breakwater pipe 112 is fixed to the concrete retaining wall 1. Therefore, the power plant is stopped, the water intake dam and the waterway are drained, The removal work of the sediment accumulated in the wave tube 112 must be performed, which causes power generation trouble and requires a large amount of cost for the removal work.
Therefore, a measure for preserving the pressure water level meter 110 from sediment accumulation is desired.

The following methods have been proposed as countermeasures against sediment accumulation by water level gauges.
(1) The maintenance method of the throwing water level meter at the pump station described in Patent Document 1 below The throwing water level meter can be secured at all times by eliminating the measurement obstacles caused by sedimentation and other sediments. In the pump station where the built-in water level gauge is installed, there is a spout near the lower end of the throw-in type water level gauge, and there are water inlets on the discharge side of the pump and on the water distribution pipe side, respectively. By installing a maintenance pipe that is inserted, and controlling the opening and closing of the motor-operated valve so that a part of the pump discharge water is used during pump operation and the in-site water is used during backup, The earth and sand can be removed without fail.
(2) Water level meter device described in Patent Document 2 below In order to easily and reliably measure the water level of the water tank, the wave breaker is composed of a fixed wave breaker and a movable wave breaker, and the moveable wave breaker By moving up and down to cover or expose the water level gauge, the water flow is made to act on the water level gauge as necessary so that the accumulated sludge can be removed.
(3) Opening and closing the opening at the lower end of the cylindrical body so that sediments such as earth and sand and dust accumulated inside can be easily discharged. An open / close lid is provided at the lower end of the cylindrical body so as to be freely openable / closable, and the open / close lid is remotely opened and closed by remote control means.

JP-A-9-138154 JP 2006-317235 A JP 2007-078561 A

However, in the maintenance method of the throw-in type water level gauge in the pump station described in the above-mentioned Patent Document 1, the sedimentation sediment is installed by using the discharge water pressure of the pump by installing the outlet of the maintenance pipe in the vicinity of the lower part of the breakwater pipe. Therefore, there is a problem that the installation of pumps and the like becomes excessive, and it is not practical in a small-scale hydropower station considering cost effectiveness.
In the water level gauge device described in the above-mentioned Patent Document 2, sedimentary sludge and the like can be removed by configuring the wave breaker tube with a fixed wave breaker tube and a movable wave breaker tube. There is a problem that this method cannot be used in a usage pattern in which a pressure gauge is installed in the vicinity of a concrete retaining wall of a water intake dam of an inflow-type power plant where the momentum of running water is weak in order to remove sludge.
In the float-type water level gauge wave breaker described in Patent Document 3, the deposit accumulated in the wave breaker tube is discharged by opening the open / close lid provided at the lower end of the cylindrical body. Although it is effective in the float type water level meter in which the detection sensor is located above the water surface, there is a problem in that it is not effective in the pressure water level meter in which the water level detection sensor is positioned at the lower end of the wave preventing tube.

  An object of the present invention is to provide a pressure water level meter and a pressure water level meter maintenance method capable of suppressing sediment accumulation with a simple configuration.

The pressure water level meter of the present invention is a pressure water level meter (10) to be installed in the vicinity of a wall (1) where the momentum of flowing water is weak, and is attached to a water level detection sensor (11) and to the wall so that it can be pulled out. And an inner wave breaker tube (12) on which the water level detection sensor is attached to the bottom surface part, and an outer wave breaker tube (13) installed so as to surround the inner wave breaker tube, The outer wave breaker tube prevents the earth and sand from being deposited around the inner wave breaker tube, and prevents the earth and sand from entering the inner wave breaker tube from the water introduction hole (12a) of the inner wave breaker tube. To do.
Here, the outer anti-wave tube, the cleaning space for cleaning the suspended sediment deposited entered between the outer breakwater tube inner breakwater tube and the outer anti-wave tube from the open surface of the securing You may be made the size which can be done.
The filled between the inner breakwater tube and the outer breakwater tube and suspended sediment may enter between the opening surface of the outer breakwater tube with inner breakwater tube and the outer breakwater tube A synthetic resin drainage material (14) that suppresses accumulation and ensures water permeability may be further provided.
The synthetic resin drainage material may be wound around an outer periphery of the inner wave breaker so as to be pulled out together with the inner wave breaker.
The synthetic resin drainage material may be a three-dimensional network structure in which a large number of gaps are formed so as to allow water to pass but not allow floating sediment to pass.
The outer breaker tube has a size that can secure a cleaning work space for cleaning the suspended earth and sand that has entered between the inner breaker tube and the outer breaker tube from the opening surface of the outer breaker tube. May be made smaller.
The wall may be a concrete retaining wall (1) of a water intake dam of a pour-type power plant, and the outer wave breaker may be flush with a water intake port of the water intake dam.
The pressure water level meter maintenance method of the present invention is a pressure water level meter maintenance method for maintaining a pressure water level meter (10) installed in the vicinity of a concrete retaining wall (1) of a water intake dam of a pouring power plant from sediment accumulation. An inner wave breaker pipe (12) having a water level detection sensor (11) attached to the bottom surface thereof is detachably attached to the concrete retaining wall, and has an outer wall with the same height as the intake dam of the intake dam. A wave tube (13) is installed so as to surround the inner breaker tube, and the outer breaker tube prevents the sediment from being deposited around the inner breaker tube. The soil is prevented from entering the inner wave breaker.
A synthetic resin drainage material (14) having water permeability is wound around the inner breaker tube so as to be pulled out together with the inner breaker tube and filled between the inner breaker tube and the outer breaker tube. Te may be prevented from being deposited enters between suspended sediment from the opening face of the outer breakwater tube and said inner breakwater tube and outer breakwater tube.
The synthetic resin drainage material may be a three-dimensional network structure in which a large number of gaps are formed so as to allow water to pass but not allow floating sediment to pass.

The pressure water level meter and the pressure water level meter maintenance method of the present invention have the following effects.
(1) By providing a fixed outer wave breaker so that the water level detection sensor surrounds the inner wave breaker installed on the bottom surface, the outer wave breaker prevents sediment from being deposited around the inner wave breaker. Therefore, sediment accumulation around the inner wave breaker can be prevented with a simple configuration.
Also, by filling synthetic resin drainage material between the inner and outer breaker tubes, suspended earth and sand can be separated from the inner and outer breaker tubes from the opening surface (upper surface) of the outer breaker tube . Since it is possible to suppress accumulation in between, it is possible to further prevent sediment accumulation around the inner wave breaker with a simple configuration.
(2) By enabling the inner breaker tube to be pulled out, the earth and sand removal work inside the breaker tube, which could not have been carried out without stopping the power generation (dam water stoppage), can be carried out even during power generation, thus reducing the overflow power. Can do.
(3) By enabling the inner breaker tube to be pulled out, replacement of synthetic resin drainage material and removal of earth and sand in the inner breaker tube can be performed safely on a flat part with good workability. be able to. Further, since the appearance inspection of the water level detection sensor can be easily performed, the life of the water level detection sensor can be extended.

It is a figure which shows the structure of the pressure level meter 10 by one Example of this invention, (a) is a top view of the pressure level meter 10 attached to the concrete retaining wall 1, (b) is the concrete retaining wall 1 It is the side view which showed the attached pressure water level gauge 10 in the cross section, (c) is a figure for demonstrating the attachment method to the concrete retaining wall 1 of the inner side wave-breaking pipe 12. FIG. It is a figure which shows the structure of the conventional pressure water level meter 110, (a) is a top view of the conventional pressure water level meter 110 attached to the concrete retaining wall 1, (b) is attached to the concrete retaining wall 1. It is the side view which showed the conventional pressure water level meter 110 in the cross section.

  For the above purpose, the water level detection sensor can be pulled out of the inner wave breaker installed on the bottom surface, the outer wave breaker is provided so as to surround the inner wave breaker, the inner wave breaker and the outer wave breaker It was realized by filling synthetic resin drainage between the two.

Embodiments of a pressure water level meter and a pressure water level meter maintenance method of the present invention will be described below with reference to the drawings.
As shown in FIGS. 1 (a) to 1 (c), a pressure water level gauge 10 according to an embodiment of the present invention has a wall having a weak momentum of flowing water such as a concrete retaining wall 1 of a water intake dam of a pouring power plant. The water level detection sensor 11, the cylindrical inner wave breaker 12, the cylindrical outer wave breaker 13 placed so as to surround the inner wave breaker 12, and the inner wave breaker are installed in the vicinity. A synthetic resin drainage 14 filled between the wave tube 12 and the outer wave breaker tube 13 is provided.

  Here, similarly to the water level detection sensor 111 shown in FIGS. 2 (a) and 2 (b), the water level detection sensor 11 is not directly affected by flowing water or damaged by the earth and sand. It is inserted in and attached to the bottom surface of the inner wave breaker 12.

The inner wave breaker 12 has an outer diameter of about 40 mm, is inserted into the water so that the bottom surface reaches the bottom of the intake dam, and has a water introduction hole 12a on the peripheral surface and the bottom surface. It is the same as the wave breaker 112 shown in 2 (a) and (b).
However, as shown in FIG. 1 (c), the inner wave breaker 12 is attached to the concrete retaining wall 1 of the intake dam so that it can be pulled out by the attachment member 15 at a portion above the water surface of the inner wave breaker 12. It differs from the wave preventing tube 112 shown in FIGS. 2 (a) and 2 (b).
Here, the attachment member 15 is attached to a place where the worker can reach from the concrete retaining wall 1, and is composed of two semi-annular members whose front ends can be coupled with bolts B. The gripping part and the attachment part for attaching the attachment member 15 to the concrete retaining wall 1 with the bolt B, with the end part of the gripping part fixed to the tip part. The two semi-annular members are made of a thin metal plate in order to give elasticity so that the inner wave breaker 12 can be taken in and out between the tips of the two semi-annular members.
As a result, the worker inserts the inner wave breaker tube 12 into the water so that the bottom surface reaches the water bottom of the intake dam, and then the inner wave breaker tube 12 from between the front ends of the two semi-annular members of the mounting member 15. The inner wave-breaking tube 12 can be attached to the concrete retaining wall 1 by inserting the end portions of the two semi-annular members with the bolt B. Further, the worker removes the bolt B from the tip ends of the two semi-annular members of the mounting member 15, pulls out the inner wave breaker tube 12 from between the tip portions of the two semi-annular members, The wave breaker 12 can be pulled out together with the synthetic resin drainage material 14.
The gripping portion of the mounting member 15 is an annular member, and the inner surface is fixed to the outer peripheral surface of the inner wave preventing tube 12 and the mounting portion can be detached from the concrete retaining wall 1 so that the worker can attach the mounting member 15 to the concrete retaining wall. After removing from 1, the inner wave breaker 12 may be pulled out together with the synthetic resin drainage material 14 by pulling up the inner wave breaker 12.

Outer breakwater tube 13 and synthetic resin drainage material 14, sediment of the inner breakwater tube 12 is deposited on the periphery of the inner breakwater tube 12 the water guide holes 12a from for suppressing entering the inner breakwater tube 12 Is.

Here, the outer wave breaker tube 13 is for suppressing sedimentation of earth and sand from the lateral direction, and has an inner diameter of about 150 mm.
In addition, since the outer wave breaker 13 is higher than the water level of the intake dam, an error occurs in the water level measurement by the water level detection sensor 11, so that it is not higher than the water level of the intake dam (for example, 3m).

The synthetic resin drainage material 14 suppresses sedimentation of floating earth and sand from the opening surface (upper surface) of the outer wave breaker tube 13 between the inner wave breaker tube 12 and the outer wave breaker tube 13 and also allows water permeability. In order to ensure and allow water to flow into the inner wave breaker tube 12 from the water guide hole 12 a of the inner wave breaker tube 12, it is filled between the inner wave breaker tube 12 and the outer wave breaker tube 13.
That is, the synthetic resin drainage material 14 is a three-dimensional network having a large number of gaps randomly formed so as to allow water to pass but not to catch floating earth and sand, such as the Hettimaron (registered trademark) body manufactured by Shinko Nylon Co., Ltd. It is a structure.

Further, since synthesis the resin drainage material 14 accumulated is suspended sediment, synthetic resin drainage materials 14 are wound around the outer periphery of the inner breakwater tube 12, so as to be periodically replaced and pull with the inner breakwater tube 12 Has been.

However, even if the synthetic resin drainage material 14 is not filled between the inner wave-breaking tube 12 and the outer wave-breaking tube 13, earth and sand around the inner wave-breaking tube 12 can be obtained by installing the outer wave-breaking tube 13. Deposition can be prevented to some extent. However, in this case, since the suspended sediment is deposited between the opening surface of the outer breakwater tube 13 the inner breakwater tube 12 and the outer breakwater tube 13, results will require periodic cleaning, cleaning In order to secure a working space, it is necessary to make the inner diameter of the outer wave breaker 13 about 1.5 m.
In addition, since it is not necessary to secure this cleaning work space by filling the synthetic resin drainage material 14, the inner diameter of the outer wave breaker tube 13 can be reduced to about 150 mm, which is smaller than the size capable of securing the cleaning work space.

  In the pressure water level gauge 10 configured as described above, even if it is installed near the concrete retaining wall 1 of the intake dam of a flow-type power plant where the momentum of flowing water is weak, earth and sand accumulate in the inner wave breaker 12. Therefore, the water level can be accurately measured by the water level detection sensor 11.

  In the above description, the inner wave-breaking tube 12 and the outer wave-breaking tube 13 are cylindrical, but may be rectangular as long as they are tubular.

DESCRIPTION OF SYMBOLS 1 Concrete retaining wall 10,110 Pressure level meter 11,111 Water level detection sensor 12 Inner wave-breaking pipe 12a, 112a Water guide hole 13 Outer wave-breaking pipe 14 Synthetic resin drainage material 15 Mounting member 112 Wavebreaking pipe B Bolt

Claims (10)

A pressure water level meter (10) for installation near the wall (1) where the momentum of running water is weak,
A water level detection sensor (11);
An inner wave breaker tube (12) attached to the wall in a detachable manner and the water level detection sensor attached to a bottom surface;
An outer wave breaker (13) installed so as to surround the inner wave breaker,
Sediment is prevented from entering the inner wave breaker tube from the water introduction hole (12a) of the inner wave breaker tube so that the outer wave breaker tube does not accumulate sediment around the inner wave breaker tube,
A pressure water level gauge characterized by that. The outer breaker tube has a size that can secure a cleaning work space for cleaning the suspended earth and sand that has entered between the inner breaker tube and the outer breaker tube from the opening surface of the outer breaker tube. The pressure water level gauge according to claim 1, wherein The filled between the inner breakwater tube and the outer breakwater tube and suspended sediment may enter between the opening surface of the outer breakwater tube with inner breakwater tube and the outer breakwater tube The pressure water level meter according to claim 1, further comprising a synthetic resin drainage material (14) that suppresses accumulation and ensures water permeability. The pressure water level meter according to claim 3, wherein the synthetic resin drainage material is wound around an outer periphery of the inner wave breaker so as to be pulled out together with the inner wave breaker.   The pressure water level meter according to claim 3 or 4, wherein the synthetic resin drainage material is a three-dimensional network structure in which a large number of gaps are formed so as to allow water to pass but not allow floating sediment to pass. The outer breaker tube has a size that can secure a cleaning work space for cleaning the suspended earth and sand that has entered between the inner breaker tube and the outer breaker tube from the opening surface of the outer breaker tube. The pressure water level gauge according to any one of claims 3 to 5, wherein the pressure water level meter is also made smaller. The wall is a concrete retaining wall (1) of a water intake dam of a pouring power plant,
The outer wave breaker is flush with the intake dam of the intake dam,
The pressure water level gauge according to any one of claims 1 to 6, wherein A pressure water level meter maintenance method for protecting a pressure water level meter (10) installed near a concrete retaining wall (1) of a water intake dam of a flow-type power plant from sediment accumulation,
An inner wave breaker tube (12) having a water level detection sensor (11) attached to the bottom surface is removably attached to the concrete retaining wall,
An outer wave breaker (13) having the same height as the intake dam of the intake dam is installed so as to surround the inner wave breaker;
Sediment is prevented from entering the inner wave breaker tube from the water introduction hole (12a) of the inner wave breaker tube so that the outer wave breaker tube does not accumulate sediment around the inner wave breaker tube,
A pressure water level meter maintenance method characterized by the above. A synthetic resin drainage material (14) having water permeability is wound around the inner breaker tube so as to be pulled out together with the inner breaker tube and filled between the inner breaker tube and the outer breaker tube. Te, suspended sediment is characterized by inhibiting the entering and depositing it between the outer breakwater tube inner breakwater tube and the outer breakwater tube from the opening face of the pressure level according to claim 8 Total maintenance method.   The pressure water level meter maintenance method according to claim 9, wherein the synthetic resin drainage material is a three-dimensional network structure in which a large number of gaps are formed so as to allow water to pass but not allow floating sediment to pass.

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