JPH0348478B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Description of the Technical Field] The present invention relates to a drain funnel installed on a floor surface from which radioactive waste liquid flows out in a nuclear power plant or the like.

[Technical background of the invention and its problems]

Drain water from pumps installed in buildings such as nuclear power plants, and radioactive waste liquids such as decontamination waste liquids flow into funnels installed on the floor of the building, and then are sent to waste liquid collection tanks and waste liquid tanks via drain piping. It will be done.

Conventionally, drain funnels in nuclear power plants and other facilities are made of steel, so they corrode easily, and the rust that develops can be carried downstream to equipment such as pumps or tanks, potentially damaging these equipment and causing damage to the facility. This increases the amount of rust generated overall and puts a burden on the disposal of radioactive waste liquid.

In addition, in order to reduce the amount of rust generated, funnels are cleaned, rust removed, and painted, but since funnels are fixed to the floor, they are difficult to clean and are difficult to clean completely. It is.

Furthermore, if rust accumulates in a part of the drain pipe and causes clogging, if water flows in from funnels connected to the same drain pipe, radioactively contaminated water may flow back from other funnels. In that case, it will be necessary to treat the water on the floor and remove radioactive contamination.

In addition, rooms where highly radioactive waste liquids are stored are controlled under negative pressure, but if the sealed water in the drain funnel dries or disappears, atmospheric pressure will be applied to the room connected to the same drain pipe. Air flows backwards from the room through the drain pipe, causing radioactive rust and dust attached to the drain pipe to fly up, contaminating the entire building with radioactivity.

Furthermore, the current situation has problems such as the need to remove the lid of the funnel each time to check the level of the sealing water.

[Purpose of the invention]

The present invention has been made to eliminate the above-mentioned problems, and its first purpose is to provide a drain funnel that can be removed for easy cleaning and inspection. .

The second purpose is to prevent the occurrence of corrosion and rust by using corrosion-resistant materials such as plastic for the funnel components, maintain the integrity of downstream pumps, tanks, etc., and reduce the amount of rust throughout the facility. It is an object of the present invention to provide a drain funnel that can reduce the amount of waste liquid and reduce the amount of waste liquid treatment.

The third purpose is to prevent the backflow of radioactively contaminated water and air, thereby eliminating the need to process water and dust and remove radioactive contamination in the event of a backflow, thereby reducing exposure, waste, and nuclear power. An object of the present invention is to provide a drain funnel that can maintain cleanliness in power plants, etc.

A fourth object is to provide a drain funnel that allows the level of sealing water to be checked without removing the lid of the funnel, thereby shortening the working time and reducing the radiation exposure of the person checking.

[Summary of the invention]

In order to solve the above problems, the drain funnel of the present invention is removably buried in the floor of a building where radioactive condensate is processed, the upper opening is closed with an openable funnel lid having a drain inflow hole, and the inside of the bottom surface is closed. a funnel main body having a double cylindrical drain pipe cover part which fits into the drain pipe and has a drain outlet therein protrudingly formed therein, and a color-coded display part that displays the color according to the water level; a stopper attached to the upper opening of the drain piping cover; a seal plug that is floatably installed in the drain piping cover and abuts the stopper when floating to close the upper opening of the drain piping cover; and the drain piping cover. A drain flow hole is formed below the top of the drain piping cover to cover the piping cover, and the lower part is fixed to the core fixing frame formed at the bottom of the funnel body, and the upper part is attached to the funnel lid via the core fixing rod. a water-sealing core fixed to the funnel body; and a water level gauge having a reflector fixed to the upper part of the float housed in the funnel body to reflect the color of the color-coded display section directly upward; Funnel body,
The lid, core, seal plug, and stopper are made of corrosion-resistant materials.

[Embodiments of the invention]

An embodiment of the drain funnel according to the present invention will be described below with reference to the drawings.

Reference numeral 1 indicates a funnel body, and the funnel body 1 mainly includes a core 2 for sealing water, a funnel lid 22 that can be opened and closed to cover the upper opening, and a seal plug 1.
4. Stopper 16 and float type level meter 1
9 is included. This funnel body 1 is
A drain outlet 6 is bored inside the drain outlet 6, which is protruded toward the inside of the bottom surface in order to fit into the drain pipe.
A heavy cylindrical drain pipe cover part 7, a level meter housing cylinder 8 surrounding a float type level meter 19 provided on the side, a color-coded display part 9, a funnel handle 10 attached to the upper end of the funnel body 1, and a funnel. It is composed of a supporting part 11 and is buried in the floor 12.

The core 2 for water sealing includes a core body 2a and a core fixing rod 3.
It is composed of a core leg 4 with a gap and a space, and is fixed to the funnel body 1 by a core fixing frame 5. This core body 2a covers the drain pipe cover portion 7 and can be taken in and out from the upper opening of the funnel body 1. Moreover, the position between the core legs 4 is set below the top of the drain pipe cover part 7 for water sealing.

The seal plug 14 has a cylindrical shape with a closed upper end surface, has a specific gravity that allows it to float in water, and is placed on the drain outlet 6 by leg portions 15 having flow passage holes.

The stopper 16 is cylindrical, has an open top, a tapered opening 25 at the bottom, and has a screw 17 cut into its outer circumferential surface. The tapered opening 25 at the bottom of the stopper 16 is closed by the upper surface of the seal plug 14 coming into contact with the tapered surface.

Furthermore, a handle 18 is provided on the upper end surface, and a screw 17 is provided.
It is fixed to the drain pipe cover part 7 by.

The float type level meter 19 is composed of a float 19a, a reflector support rod 20, and a reflector 21, and is housed in a level meter housing tube 8 provided in the funnel body 1.

The funnel lid 22 has a large number of funnel holes 23, and is placed on the upper part of the funnel support part 11 so that it is flush with the floor 12.

The funnel body 1 is fixed to the floor 12 by the funnel body 1 itself and the funnel support part 11, and is fixed to the drain pipe 13 by covering the drain pipe 13 with the drain pipe cover part 7.

Next, the operation of the drain funnel having the above structure will be explained.

(B) Water flow Drain led from the pump drain piping, decontamination waste liquid piping, etc. or drain flowing onto the floor 12 passes through the funnel hole 23 of the funnel lid 22 and collects in the bottom of the funnel main body 1, and then drains into the core leg 4. It flows into the core body 2a through the gap.

As the water level 26 rises, the drain passes over the drain piping cover 7 and reaches the cavity 24 of the stopper 16.
The water passes through the gap between the legs 15 and flows downwardly, hitting the seal plug 14 and flowing into the drain pipe 13 from the drain outlet 6.

(b) Water sealing When the drain transfer is completed, the liquid level 26 inside the funnel body 1, core 2, and level meter housing tube 8 is the same as the top of the drain pipe cover 7, and remains constant unless it dries. .

In this state, a water seal is formed due to the difference in water head from the base of the core leg 4 to the water surface, and air does not flow back from the drain pipe 13 to the funnel body 1.

(c) Prevention of backflow of water and air When water tries to flow back from the drain pipe 13 to the funnel body 1, the seal plug 14 is pushed up by the water and floats on the water, causing the stopper 16
The tapered opening 25 of the pipe is in close contact with the pipe, and the flow of water is stopped.

In the unlikely event that the water accumulated inside the funnel body 1 dries and disappears, the water seal breaks, and air attempts to flow back from the drain pipe 13 to the funnel body 1, the seal plug 14 will be pushed up by the pressure of the air. , it comes into close contact with the tapered opening 25 of the stopper 16, and the flow of air is stopped.

If the pressure inside the drain pipe 13 is higher than the inside of the funnel body 1, this state continues, and when the pressure equalizes, the seal plug 14 is separated from the tapered opening 25 at the bottom of the stopper 16, and the leg 15 comes into contact with the drain outlet 6. decreases to

(d) Checking the water surface The water in the funnel body 1 and the core body 2a flows through the gap between the core legs 4, and the water in the funnel body 1 and the level meter housing cylinder 8 flows through the lower opening of the level meter housing cylinder 8. The funnel body 1, the core body 2a, and the water surface 26 in the level meter housing cylinder 8 are at the same level.

In the float type level meter 19, a float 19a floating on the liquid level 26 in the level meter housing cylinder 8 provided on the side of the funnel body 1 moves up and down in accordance with the rise and fall of the liquid level, and the float 19a and the reflecting plate 21 are The reflector 21 is moved up and down via the connected reflector support rod 20, and the water level inside the funnel body 1 can be confirmed by viewing the position of the reflector 21 from directly above.

That is, by looking at the color of the part where the reflective plate 21 contacts the color-coded display section 9, which is colored in red, yellow, blue, etc. in advance according to the water level in the level meter housing tube 8, the inside of the funnel body 1 can be detected. You can check the water level.

To check the color of the part where the color-coded display section 9 and the reflective plate 21 are in contact, shine a flashlight or the like from directly above the reflector plate 21, and the light will be reflected by the reflector plate 21 and hit the color-coded display unit 9. It is reflected again, and the reflection plate 21
It is possible to see it from directly above because it is reflected again.

(e) Removal, disassembly and cleaning of funnel Funnel lid 22 that closes funnel body 1
can be removed by inserting a finger or a stick into the funnel hole 23 and lifting it.

The core 2 can be removed by pulling the core fixing rod 3 by hand as the core legs 4 come off from the core fixing frame 5.

By manually pulling the funnel handle 10, the funnel body 1 is removed from the drain pipe 13 at the drain pipe cover part 7, and the funnel support part 1 is removed.
1. The funnel body 1 can be separated from the floor 12 and removed.

The float type level meter 19 can be removed from the level meter housing tube 8 by turning the removed funnel body 1 upside down.

When the stopper 16 grips and turns the internally threaded handle 18, the threaded portion 17 rotates and can be removed from the drain pipe cover portion 7.

The seal plug 14 can be removed by removing the stopper 16 and then turning the funnel body 1 upside down.

The disassembled parts can be cleaned by washing with water or the like.

〔Effect of the invention〕

The present invention has the following effects.

Funnel body 1 and funnel lid 22,
Since the core 2, etc. can be easily attached and detached, cleaning, inspection, and maintenance can be easily performed by simply washing with water.

By using corrosion-resistant materials, corrosion and rust do not occur, so it is possible to maintain the integrity of downstream pumps and tanks, reduce the amount of rust generated throughout the facility, and reduce the effort involved in waste liquid treatment.

This eliminates the work of removing radioactively contaminated water, water, dust, and radioactive contamination when air backflows, reducing the generation of radioactive waste such as rags used for decontamination, reducing radiation exposure for workers, and reducing nuclear energy. It is possible to maintain the cleanliness of power plants, etc.

The liquid level of the sealing water can be confirmed simply by illuminating it with a flashlight or the like without removing the lid 22 that closes the funnel body 1, thereby shortening the work time and reducing the exposure of the person checking.

[Brief explanation of drawings]

The figure is a longitudinal sectional view showing one embodiment of the drain funnel according to the present invention. 1... Funnel body, 2... Core, 4... Core leg,
6...Drain outlet, 7...Drain piping cover part, 1
2...Floor, 13...Drain piping, 14...Seal plug, 16...Stopper, 19...Float type level meter, 22...Funnel lid, 23...Funnel hole.

Claims (1)

[Claims] 1. It is removably buried in the floor of the building where radioactive condensate is processed, and the upper opening is closed with an openable and closable funnel lid that has a drain inflow hole. It fits into the drain pipe on the inside of the bottom surface and has a drain outlet inside. 2.
a funnel body in which a heavy cylindrical drain pipe cover protrudes and is formed with a color-coded display part that displays colors according to the water level; a stopper attached to the upper opening of the drain pipe cover; a seal plug which is installed in the drain pipe cover part so as to be freely floating and which contacts the stopper when floating to close the upper opening of the drain pipe cover part; and a seal plug which covers the drain pipe cover part and extends below the top of the drain pipe cover part. A water-sealing core having a drain flow hole formed therein, the lower part of which is fixed to a core fixing frame formed at the bottom of the funnel body, and the upper part of which is fixed to the funnel lid via a core fixing rod; and the funnel body. a water level gauge having a reflector fixed to the upper part of the float stored in the funnel body, the lid, the core,
A drain funnel characterized in that the seal plug and stopper are made of corrosion-resistant material.