JP3240331U - leak detector - Google Patents

Abstract

A leakage detection device for automatically detecting fluid leakage from a buried tank or piping is provided. A portion of an oiling pipe (11) buried underground is a double pipe (30) including a first pipe (31) used as the oiling pipe and a second pipe (32) covering the first pipe (31). A detection sensor 15 is arranged between the first pipe 31 and the second pipe 32 to detect leakage of the organic solvent. The detection sensor 15 is connected to the leak detector 21 of the leak detector panel 20 via a lead wire 25 . As a result, when the organic solvent leaks from the first pipe 31, the leak detection device 21 detects the leak with the detection sensor 15, emits a sound from the buzzer 22, and notifies the person in charge of the leak of the organic solvent. . [Selection drawing] Fig. 1

Description

The present invention relates to a leak detection device.

Some liquids contained in buried tanks or fluids flowing through pipes are considered hazardous materials. Leakage of dangerous fluid from structures such as buried tanks or pipes must be dealt with immediately, even if the leak is slight.
As such a fluid, for example, in order to detect the leakage of an organic solvent, an organic solvent leakage detection tool to which an organic solvent leakage detection agent is attached in a uniform thickness is attached to a buried tank, pipe, or the like. (See, for example, Patent Document 1).

With this organic solvent leakage detector, it is possible to easily visually confirm whether or not the organic solvent is leaking, based on the presence or absence of color development. However, the actual situation is that it is difficult to immediately deal with the leakage of the organic solvent by visual inspection by a person. This is because it is not desirable in terms of cost or the like to have a person always stationed to check for leaks.

Japanese Patent Application Laid-Open No. 2001-318020

Therefore, the present invention proposes a leakage detection device for automatically detecting fluid leakage from an embedded tank or a pipe.

A leak detection device according to one aspect of the present disclosure forms a first layer and a second layer in a state in which the fluid does not leak from the inside of a structure in which the fluid is stored or flows, and the first layer and the second layer, a detection sensor for detecting the fluid is arranged, and the detection sensor detects the fluid leaking from the first layer.

The present invention can automatically detect fluid leakage from buried tanks or pipes.

It is a figure explaining the application example of the leak detection method based on one Embodiment of this invention. It is a figure explaining the application example of the leak detection method based on other one Embodiment of this invention. It is a figure explaining the structure example of the inner surface layer of the location where the detection sensor is arranged. It is a figure explaining the example of the connection method of hollow glass fiber. FIG. 4 is a diagram for explaining an example structure of an inner surface layer at the end of a hollow glass fiber; It is a figure explaining the structural example of the penetration part which a detection sensor penetrates an inner surface layer. It is a figure explaining the example of a connection part.

EMBODIMENT OF THE INVENTION Hereafter, the form for implementing this invention is demonstrated, referring a figure.
It should be noted that the embodiment described below is merely an example including modifications, and the technical scope of the present invention is not limited to this. Various modifications are also included in the technical scope of the present invention.

FIG. 1 is a diagram illustrating an application example of a leak detection method according to an embodiment of the present invention.
The application example shown in FIG. 1 is for detecting leakage in a pipe for injecting fluid into an underground tank buried underground or for sucking fluid in an underground tank.
Fluids are considered hazardous materials. Here, the fluid is assumed to be an organic solvent such as toluene or methylcyclohexane, and is hereinafter referred to as an organic solvent. The piping for leak detection is assumed to be a lubricating pipe.

Note that toluene is an organic compound belonging to aromatic hydrocarbons, and has a structure in which one hydrogen atom of benzene is substituted with a methyl group. It is a colorless and transparent liquid, volatile at room temperature, and not only flammable, but also has an anesthetic effect on the human body and is highly toxic.
Methylcyclohexane is produced by the hydrogenation of toluene, and hydrogen can be extracted by dehydrogenation with a catalyst. Therefore, as a type of organic hydride, research is being promoted as a means of stably storing and transporting hydrogen. Less toxic than toluene.
Such organic solvents are expected to be widely used at hydrogen stations and the like. In view of the toxicity of organic solvents and the background, it is considered important to ensure early detection of leakage of organic solvents. For this reason, an organic solvent is assumed here as the fluid.

41 in FIG. 1 is a manhole. The lubricating pipe 11 is buried underground from the middle and is exposed from the underground inside the manhole 41. - 特許庁It is difficult to visually detect leakage of the organic solvent from the underground portion of the lubricating pipe 11 .
For this reason, this example is applied to automatically detect leaks occurring in the portion of the lubricating pipe 11 that is buried underground. Therefore, the part of the lubricating pipe 11 buried underground is connected to the lubricating pipe 11 by welding or the like, and the first pipe 31 (first layer) used as the lubricating pipe and the first pipe 31 are covered. It is a double pipe 30 having a second pipe 32 (second layer).

The connection between the lubricating pipe 11 and the double pipe 30 is made inside the connection box 10 . The lubricating pipe 11 is connected to the first pipe 31 via the flange 12 . Another flange 42 exists in the manhole 41, and the double pipe 30 is formed between the two flanges 12, 42. As shown in FIG.

The connection box 10 is also provided with a lead wire 25 and a pipe 13 into which a detection sensor 15 for detecting leakage is inserted. The detection sensor 15 is, for example, a sensor cable whose capacitance changes with an organic solvent. A sealing 14 is provided to prevent water or the like from entering the pipe 13 .

The detection sensor 15 is inserted from the flange 12 to the flange 42 between the first pipe 31 and the second pipe 32 of the double pipe 30 . Thereby, the detection sensor 15 is adapted to change the capacitance when leakage occurs in any of the first tubes 31 .

the lead wire 25; It is connected to the leak detector board 20 . Specifically, it is connected to the safety retainer 23 . The leak detector panel 20 automatically detects a leak occurring in the first pipe 31, and notifies the user when the leak is detected. For that purpose, a leakage detection device 21 and a buzzer 22 are provided.

The leakage detection device 21 detects, for example, a change in the capacitance of the detection sensor 15 as a change in voltage value via the lead wire 25, and determines whether or not leakage has occurred in the first pipe 31 from the detected voltage value. to specify. For this reason, the leakage detection device 21 is connected to a DC (Direct Current) terminal 24 to which a DC voltage is applied, and is grounded. The presence or absence of leakage is determined, for example, by comparing a threshold determined for each type of organic solvent with the detected voltage value.

When the leak detection device 21 identifies that a leak has occurred, the buzzer 22 emits a sound to notify the person in charge of the fact. This allows the person in charge to immediately respond to the leak of the organic solvent. By taking immediate action, it is possible to minimize the damage caused by leakage.

In this way, in this example, the part of the pipe where leakage should be detected is the double pipe 30, and the detection sensor 15 is arranged between the first pipe 31 and the second pipe 32 in the double pipe 30. . Thereby, the detection sensor 15 is used to automatically detect any leakage occurring in the first pipe 31 .
Therefore, even if the pipe or a part of the pipe is buried in a place where it is difficult to visually recognize, for example, in the ground, leakage can be automatically detected. In addition, when leakage is detected, the sound emitted by the buzzer 22 enables the person in charge to immediately recognize that fact, which makes it easier to minimize the amount of leaked organic solvent. As a result, the damage caused by the leaked organic solvent can be minimized.

Even if damage such as a hole or crack occurs in the first tube 31 , damage such as a hole or crack does not necessarily occur in the second tube 32 . Even if the second pipe 32 is damaged, the amount of organic solvent leaking from the second pipe 32 is smaller than the amount of organic solvent leaking from the first pipe 31 . Also from this, it is possible to further suppress the damage caused by the leakage of the organic solvent.

The type of detection sensor 15 that detects leakage is not particularly limited. The reason why the detection sensor 15, which is a sensor cable, is adopted is that even if the length of the double pipe 30 is long, it can be easily handled. The type or the like of the detection sensor 15 may be changed according to the length or area for which leakage should be detected. Since the outer second pipe 32 only needs to cover the entire first pipe 31, it may be a member that is attached after the first pipe 31 is connected by welding or the like.

FIG. 2 is a diagram illustrating an application example of a leak detection method according to another embodiment of the present invention.
The application example shown in FIG. 2 is for detecting leakage of an organic solvent stored in an underground tank buried underground. In FIG. 2, the same reference numerals are given to the same or basically the same parts as in FIG.

In this example, the leakage detector panel 20 and the connection hole 41 are connected by a pipe 61 , and the lead wire 25 is passed through the pipe 61 . Moreover, the underground tank 50 has a multilayer inner surface layer 52 (first layer) formed on the inner surface of the steel plate 51 (second layer).
A detection sensor (sensor cable) 15 is arranged between the inner surface layer 52 and the steel plate 51 . The detection sensor 15 is arranged between points A and B in FIG. Therefore, the inner surface layer 52 should be formed at least between the points A and B. The detection sensor 15 and the lead wire 25 are connected by a connection portion 45 .

FIG. 3 is a diagram illustrating a structural example of the inner surface layer where the detection sensor is arranged. Note that this structural example of the inner surface layer 52 is merely an example, and any structure may be used as long as the organic solvent stored in the underground tank 50 does not leak unless a problem occurs.

As shown in FIG. 3, hollow glass fibers 501 are attached to the inner surface of a steel plate 51 in this example. The detection sensor 15 is placed in the void where the hollow glass fiber 501 is not present. A portion of the detection sensor 15 is inserted into the split tube 510 and protected.
The split tube 510 into which the detection sensor 15 is inserted is higher (thicker) than the hollow glass fiber 501 . For this reason, an oil-resistant double-sided tape 502 is attached to the hollow glass fiber 501 adjacent to the split tube 510 , and an adhesive PET film 504 is attached to the two double-sided tapes 502 .

A putty 503 is applied to the side of the double-sided tape 502 opposite to the side facing the split tube 510 . The outside of the inner surface layer 52, that is, the side that contacts the organic solvent, is formed with, for example, an ultraviolet curing type FRP (fiber reinforced plastic) 505 over the entire surface. This FRP 505 corresponds to the inner surface layer 52 in a narrow sense.

FIG. 4 is a diagram illustrating an example of a method for connecting hollow glass fibers. FIG. 5 is a diagram for explaining an example of the structure of the inner surface layer of the end portion of the hollow glass fiber.
As shown in FIG. 4, the connection of two hollow glass fibers 501 is done by sticking a PET film 504 on them. The ends of the hollow glass fibers 501 are coated with a putty 503 as shown in FIG.

FIG. 6 is a diagram for explaining an example structure of a penetrating portion through which the detection sensor penetrates the inner surface layer.
As shown in FIG. 6, the split tube 510 into which the detection sensor 15 is inserted penetrates the FRP 505 at this through portion.
FRP 505 is actually formed (eg, applied) after placement of sensing sensor 15, including, for example, split tube 510. FIG. A putty 503 is applied to stabilize the detection sensor 15 including the split tube 510 .
The FRP 505 and the split tube 510 , the detection sensor 15 and the split tube 510 , and the detection sensor 15 and the split tube 510 are each sealed by a sealing material (not shown). In this manner, the inner layer 52 is prevented from leaking unless the FRP 505 is punctured or cracked.

FIG. 7 is a diagram illustrating an example of a connecting portion;
A plurality of pipes 71 to 73 are connected to the connecting portion 45 . Both ends of the detection sensor 15 are connected to connectors 74 respectively. A lead wire 25 is connected to each connector 74 . One of the two connectors 74 is a switching connector 74 to which a communication line 75 is connected in addition to the lead wire 25 .

In this example, similarly to the double pipe 30 , the leak detector 21 of the leak detector panel 20 can automatically detect leaks occurring in the inner layer 52 of the underground tank 50 . It can be estimated that the occurrence of leakage in the inner surface layer 52 is caused by a physical force acting on the steel plate 51 or deterioration of the steel plate 51 due to rust or the like. Therefore, the occurrence of leakage in the inner surface layer 52 can be considered to be the occurrence of leakage from the steel plate 51 or the possibility of occurrence of leakage.
This example makes it possible to respond to such leaks earlier and more reliably. The inner surface layer 52 functions to reduce the amount of organic solvent leaking from the underground tank 50 even if the steel plate 51 is damaged and the organic solvent leaks from the steel plate 51 .

In this example, it is assumed that the occurrence of leakage in the existing underground tank 50 is detected, but the underground tank 50 may be buried in the future. In that case, the detection sensor 15 may be arranged between the steel plate 51 and the outer surface layer formed on the outer side thereof.

10 connection box, 11 lubrication pipe, 15 detection sensor, 20 leak detector panel, 21 leak detection device, 22 buzzer, 25 lead wire, 30 double pipe, 31 first pipe, 32 second pipe, 50 underground tank , 51 steel plate, 52 inner layer, 505 FRP.

Claims (4)

Forming the first layer and the second layer in a state in which the fluid does not leak from the inside of the structure in which the fluid is stored or flowed,
a detection sensor for detecting the fluid is disposed between the first layer and the second layer;
detecting the fluid leaking from the first layer by the detection sensor;
Leak detection device. the fluid is an organic solvent;
The leakage detection device according to claim 1. The structure is a double pipe comprising the first layer and the second layer.
The leak detection device according to claim 1 or 2. wherein the structure is an underground tank buried underground comprising the first layer and the second layer;
The leak detection device according to claim 1 or 2.

Images