JPS63280129A - Drain funnel - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention prevents air from flowing backward through a drain funnel due to a pressure difference between two rooms that share the same drain pipe in waste liquid collection equipment in a building. The present invention relates to a method, and particularly to a drain funnel suitable for use in cases where prevention of the spread of contamination is strongly required, such as in nuclear power plants.

[Conventional technology]

Conventionally, waste liquid collection equipment installed in nuclear power plant buildings is
If rust, dirt, etc. accumulate in a part of the drain piping that makes up the waste liquid collection equipment and it becomes clogged, drain flows in from part of the multiple drain funnels connected to the same drain pipe. It was invented for the purpose of preventing drain contaminated with radioactivity from flowing back from other drain funnels. In other words, a seal plug is built into the end (top) of the drain pipe that rises inside the drain funnel, and the buoyancy of the drain that flows backwards is used to plug the drain pipe and prevent other drains from flowing. This prevents the drain flowing in from the funnel from flowing backwards. Therefore, it does not have the function of preventing backflow of high-pressure air that is caused by a pressure difference between two chambers that share the same drain pipe and enters through other drain funnels and the common drain pipe. The air backflow prevention method considered in this prior art (Japanese Patent Application Laid-Open No. 60-88734) is a water sealing method, which is the same as that generally employed in the past. In other words, the structure consists of a drain funnel body, a core built into the drain funnel, and seal water stored in a liquid reservoir at the upper end of the drain pipe. In some cases, it is completely impossible to prevent the backflow of high pressure air that enters through other drain funnels and the common drain pipe due to the pressure difference between two chambers sharing the same drain pipe. It has the disadvantage of becoming.

In addition, the conventional technology described in JP-A-50-144262 has a structure in which the drain inlet is closed with a stopper, and although it is possible to prevent the backflow of odors, It does not have sufficient function or effect to prevent the backflow of high pressure air caused by the pressure difference.

[Problem that the invention seeks to solve]

The above-mentioned conventional technology is designed to prevent two chambers sharing the same drain pipe when the seal water in the water seal inside the drain funnel evaporates and the seal water decreases below a predetermined water level and the water seal function is lost. No consideration was given to preventing backflow of high-pressure air caused by the pressure difference between
There was a problem in that it was necessary to carry out a visual inspection patrol before the water level fell below a predetermined level, and to replenish seal water if necessary. It takes a huge amount of man-hours to check whether the amount of seal water in each of the huge number of drain funnels installed in a nuclear power plant is appropriate or not, and to replenish the seal water if it is found to be inappropriate. become. In addition, when inspecting and refilling the seal water in the water seal inside the drain funnel, as the work progresses from the first drain funnel to the last drain funnel, the drain funnel where the seal water was first filled will seal due to evaporation. It is not efficient as there are many cases where problems such as water shortage occurring again occur. Furthermore, in order to inspect and replenish the seal water, it is necessary for workers to enter work areas under high radiation conditions to inspect and replenish the seal water, and from the perspective of preventing radiation exposure. There was also a big problem.

The purpose of the present invention is to achieve prevention of backflow of high-pressure air from the drain funnel caused by a pressure difference between two chambers that share the same drain piping, regardless of the presence or absence of seal water in the water seal section in the drain funnel. It is something to do. That is, the object of the present invention is to provide a method for preventing backflow of air from a drain funnel that does not use a water seal method (does not require sealing water).

Furthermore, the present invention not only prevents the backflow of air from the drain funnel, but also prevents the backflow of drain containing radioactively contaminated water and the like at the same time.

[Means for solving problems]

The above object has a drain funnel main body, a funnel hole, a funnel lid removably provided at the upper part of the main body, a drain outlet and a drain flow hole provided at the lower part of the main body, and the funnel In a drain funnel whose main component is a core provided at the bottom of the lid, a drain and air backflow prevention plate is provided at the bottom of the funnel lid, and the prevention plate is brought into close contact with the drain flow hole of the core to prevent backflow. In order to prevent this, a tension member is provided between the core and the funnel lid, so that the backflow prevention plate and the funnel lid are engaged with each other. Equipment installed inside nuclear power plants, etc.

This is achieved by applying it to the collection of condensate discharged from piping, etc. Further, packing made of a rubber elastic member is provided on at least one of the cocoon heavy core or the backflow prevention plate,
Furthermore, the above object can be achieved more effectively by using a spring member, a magnet member, a shape memory alloy member, or a bimetal member as the tension member.

[Effect]

The drain funnel according to the present invention is a spring member.

a tensioning member that is a magnetic member, a shape memory alloy member, or a bimetallic member; the tensioning member engages the funnel lid, and thus senses a change in weight or temperature to open and close a drain passage hole to the drain piping; In addition, the main part is composed of a backflow prevention plate that prevents backflow of high-pressure air when it occurs due to a pressure difference between two units sharing the same drain pipe.

The inside of the drain funnel is divided into an upper part and a lower part by a core having a drain passage hole of an appropriate size in the center. Under normal conditions, the drain outlet on the core is
It is closed from below by the aforementioned backflow prevention plate which is larger in size.

When drain discharged from equipment, piping, etc. flows into the drain funnel of the present invention configured as described above, the drain initially flows into the upper part of the drain funnel, which is divided into an upper part and a lower part by a core and a backflow prevention plate. The spring member and magnet member that engage the backflow prevention plate with the funnel lid.

The tension member, which may be a shape memory alloy member or a bimetallic member, becomes immersed in the drain. As a result, the tension member changes its shape by sensing the weight or temperature change due to the inflow of drain, and the backflow prevention plate supported by the tension member opens. As a result, the drain accumulated in the upper part of the drain funnel flows out from the opened drain flow port to the lower part of the drain funnel, and is further led from the lower part of the drain funnel to the drain pipe and discharged.

In addition, if a backflow of high-pressure air occurs through the drain pipe due to a pressure difference between two units that share the same drain pipe, the drain funnel will be closed except during normal times, that is, when drain is flowing into the drain funnel. Backflow of air is prevented by a backflow prevention plate. Furthermore, as mentioned above,
The drain passage hole on the core inside the drain funnel is blocked from below by a backflow prevention plate, so even if the pressure is applied when air tries to flow back, the backflow prevention plate will not malfunction, and the drain passage hole will be closed. It remains securely occluded and backflow of air is prevented. In addition, the drain funnel of the present invention not only prevents the backflow of air, but also prevents the backflow of condensate reliably even when contaminated water or other condensate flows backflow through the drain piping, due to the same effect as the above-mentioned backflow of air. No malfunctions. Namely.

The drain funnel of the present invention does not prevent the drain from flowing in due to the action of the backflow prevention plate installed inside the drain funnel, and also reliably prevents the flow of air flowing back through the drain piping. It provides action.

〔Example〕

Hereinafter, a first embodiment of the drain funnel according to the present invention will be described.
This will be explained using FIGS.

FIG. 1 is a sectional view showing a drain funnel according to the present invention in a normal state and in a state in which backflow of air is prevented. In FIG. 1, reference numeral 1 indicates a drain funnel body 1, and a core 3 is provided in the drain funnel body 1 so as to divide the inside of the drain funnel body 1 into a drain funnel upper part 11 and a drain funnel lower part 12. It is being A drain flow hole 9 of an appropriate size is provided in the center of the core 3, and the core 3 allows drain discharged from the equipment and piping to flow into the drain funnel body 1 to quickly flow through the core 3. It is set with an appropriate inclination so as to be guided to the drain flow hole 9 located at the center of the top of the child 3. The drain flow hole 9 is opened and closed by a backflow prevention plate 7.

In particular, when in the closed state, the backflow prevention plate 7 closes the drain passage hole 9 from below, as shown in FIG. Further, the backflow prevention plate 7 is provided with a packing 8 which is a rubber member so that the drain flow hole 9 is reliably blocked. The opening and closing of the backflow prevention plate 7 is performed by the expansion and contraction of the tension member 4, and is constructed as follows. Hooks 5 are provided at both ends of the tension member 4, one end of which is fixed to a hanger 6 at the center on the backflow prevention plate 7, and the other end to a hanger 6 at the center of the funnel lid 12. Since the backflow prevention plate 7 is supported by the tension member 4 in this manner, it is opened and closed by the expansion and contraction of the tension member 4 as described above. As mentioned above, the tension member 4 and the funnel lid 12
The backflow prevention plate 7 is connected to the hook 5 and the hanger 6.
This has the advantage that maintenance can be performed very easily even when maintenance and inspection work such as replacement is required. The tension member 4 is a member that changes shape by sensing a change in weight, such as a spring member or a magnet member, and the tension member 4 itself is properly placed inside the drain flow hole 9, that is, It is set up so that everything fits together without any shortage. Furthermore, the shape of the tension member 4 is
The backflow prevention plate 7 is designed to be in a closed state under normal conditions when there is no inflow of condensate discharged from equipment and piping, and to prevent backflow when the shape changes upon sensing a change in weight due to the inflow of condensate. The plate 7 is set to be in an open state.

The arrows shown in FIG. 1 indicate the flow of high-pressure air that is generated by a pressure difference between two chambers sharing the same drain pipe 2 and flows back through the drain pipe 2. When such a backflow of air occurs, in the drain funnel according to the present invention configured as described above, the backflow prevention plate 7 is closed in the normal state where no condensate discharged from the equipment and piping flows in.
Since it is in a closed state, it is possible to block high-pressure air from flowing back through other drain funnels and drain piping 2. Furthermore, as described above, since the backflow prevention plate 7 closes the drain passage hole 9 from below in the same direction as the flow of air flowing backward, the drain passage hole 9 is blocked by the pressure of the air flowing back. It is possible to block the air more firmly and reliably prevent backflow of air.

Figure 2 shows the drain funnel of the present invention.

FIG. 3 is a sectional view showing a state in which backflow of drain is prevented.

The arrow shown in Fig. 2 indicates that a part of the drain pipe 2 that constitutes the waste liquid collection equipment has become clogged due to accumulation of rust, dirt, etc., and as a result, other drain funnels connected to the same drain pipe have become clogged. This shows the flow of condensate flowing backwards from the The drain funnel of the present invention can also prevent such backflow of drain.

This can be reliably prevented by the same effect as in preventing backflow of air as explained in the embodiment shown in FIG.

The high-pressure air flowing back in the embodiment shown in FIG. 1 and the drain flowing back flowing back in the embodiment shown in FIG. Prevention of backflow of air and condensate as described above is extremely important.

FIGS. 3 and 4 are cross-sectional views showing the state in which the drain funnel is performing its original function of collecting and discharging drain. The drain discharged from the equipment and piping and flowing down onto the floor surface 15 passes through the funnel lid hole 13 provided in the funnel m12 at the upper part of the drain funnel body 1 to the drain funnel upper part 1 inside the drain funnel body 1.
Flows into 0. The drain flowing into the drain funnel upper part 10 passes along the upper surface of the core 3 and collects in the drain flow hole 9. In the normal state, that is, in the state where there is no drain flowing into the drain funnel, as described above, the backflow prevention plate 7
Since it is in the open state, the drain that has gathered in the drain flow hole 9 is gradually accumulated, and the tension member 4, which is set so that the entire part is accommodated in the drain flow hole 9 without any gaps, is able to drain the drain. Immersed in a pool. Drain is drain flow hole 9
When the tension member 4 is sufficiently submerged in the drain reservoir, the tension member 4, which is a spring member or a magnet member, changes its shape by sensing the change in weight. The shape changes (in this case, it stretches) by sensing changes in the shape. As a result, the backflow prevention plate 7 supported by the tension member 4 becomes open, and the drain temporarily stored in the drain funnel upper part 10 passes through the drain flow hole 9 to the drain funnel lower part 10.
1, and is further continuously drained from the drain funnel lower part 11 through the drain pipe 2 and led to the waste liquid tank.

When the flow of condensate into the drain funnel main body 1 is stopped and all the condensate that has flowed into the upper part 1o of the drain funnel is discharged to the lower part 11 of the drain funnel, the tension member 4 senses completion of discharge of the condensate and a change in weight due to disappearance. and changes shape (in this case, shrinks). As a result, the backflow prevention plate 8 supported by the tension member 4 returns to the normal state, that is, the closed state with respect to the drain flow hole 9, and the air and drain flow as shown in the embodiments of FIGS. Returns to a state where backflow of water can be prevented.

In the drain funnel according to the present invention, the tension member 4 changes shape (expands and contracts) to open and close the backflow prevention plate 7 in response to repeated inflow and discharge of drain as described above, so that when drain flows in, the tension member 4 changes its shape (expands and contracts) to open and close the backflow prevention plate 7. Air and drain from other drain funnels that attempt to discharge and flow back through the drain pipe 2 can be reliably prevented at all times.

Modifications of the invention are shown in FIGS. 5 and 6. In the embodiments shown in FIGS. 1 to 4, the shape of the core 3 is relatively complex, so when there is a need to make manufacturing easier or to reduce manufacturing costs, etc. The fifth
As shown in the modification of the present invention shown in the figure, the shape of the core 3 can be changed to a simple shape such as a flat disc.

Although it is possible to obtain the same functions as the embodiment of the present invention shown in FIGS. 1 to 4 in the modified example of the present invention shown in FIG. The advantage of this example is that the expansion and contraction of the tension member 4, that is, the opening and closing of the backflow prevention plate 7, can be performed more quickly as drain flows in and out.

A modification of the invention shown in FIG. 6 shows the main components of the invention, namely the funnel lid 12. Core 3° drain flow hole 9. In the 0-piece modification that is manufactured by integrating the tension member 4 and the backflow prevention plate 7, in order to allow drain to properly flow into the drain funnel main body 1 through the funnel cover hole 13, Lower part 1
1 airtightness.

In order to ensure watertightness and reliably prevent air and drain flow, a rubber seal 15 is attached to the lower part of the fitting part of the funnel lid 12. According to this modification, maintenance and inspection work such as replacing component parts of the drain funnel according to the present invention can be performed even more easily, and by simply removing and installing the funnel lid 12, It is possible to easily modify the conventional water-seal type drain funnel installed in some plants.

In the embodiment of the present invention shown in FIGS. 1 to 4, a material that changes shape (expands and contracts) by sensing changes in weight is used for the tension member 4, but in this modification, the tension member 4 is A member that changes shape (expands and contracts) by sensing changes, for example,
Even if a shape memory alloy member or a bimetal member is used, the same functions as the embodiments of the present invention shown in FIGS. 1 to 4 can be easily obtained.

〔Effect of the invention〕

According to the present invention, maintenance and inspection work such as replenishment of seal water, which was performed in conventional water-seal type drain funnels, is not required, and two rooms that share the same drain pipe can be connected. This has the effect of constantly and reliably preventing backflow of high-pressure air from other drain funnels caused by pressure differences between drain funnels. Further, according to the present invention, by the same effect as when preventing backflow by blowing air, it is also possible to prevent backflow of drain from other drain funnels flowing back through a common drain pipe.

As mentioned above, in conventional water-sealing type drain funnels, when there is no condensate flowing under normal conditions, such as in nuclear power plants, it is necessary to periodically replenish seal water to maintain functionality. The maintenance and inspection work of replenishing seal water to each of the huge number of drain funnels in nuclear power plant buildings required a large amount of work. Furthermore, there is a problem in that the maintenance and inspection work involves radiation exposure of the workers. However, the present invention has the great effect of completely eliminating the large amount of work involved in maintenance and inspection work and the radiation exposure of workers.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing the drain funnel of the present invention in a normal state and a state in which backflow of high-pressure air is prevented; Fig. 2 is a cross-sectional view showing a state in which backflow of drain is prevented; Figures 3 and 4 show the collection of drain, which is the function of the drain funnel itself. Cross-sectional views showing the state in which the discharge is performed, Figures 5 and 6
The figure is a sectional view showing another embodiment of the present invention. 1...Drain funnel body, 2 drain piping, 3.
... core, 4 ... tension member, 5 ... hook, 6 ...
・Hanger, 7...Backflow prevention plate, 8...Packing, 9...Drain flow hole, 10...Drain funnel upper part, 11...Drain funnel lower part, 12...Funnel lid, 13. ...Each funnel hole, 14...floor surface, 15...rubber seal.

Claims (1)

[Scope of Claims] 1. A drain funnel body, having a funnel hole, a funnel lid removably provided on the upper part of the main body, and a drain outlet and a drain flow hole provided on the lower part of the main body. In a drain funnel whose main component is a core provided at the bottom of the funnel lid, a drain and air backflow prevention plate is provided at the bottom of the funnel lid, and the prevention plate is connected to the drain flow hole of the core. A tension member is provided between the core and the funnel lid in order to bring the core into close contact with the funnel lid to prevent backflow, thereby engaging the backflow prevention plate and the funnel lid. drain funnel. 2. The drain funnel according to claim 1, characterized in that at least one of the core or the backflow prevention plate is provided with packing so that the space between them becomes airtight during backflow. 3. The drain funnel according to claim 2, wherein the packing is a rubber elastic member. 4. The drain funnel according to claim 1 or 2, wherein the tension member is a spring member, a magnet member, a shape memory alloy member, or a bimetal member.