JPH10104107A - Apparatus for locating leakage position in buried pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correctly detect a leakage position with a simple machine constitution by including a valve for switching a flow path from a plurality of suction holes sucking gas in a plurality of detection holes and a gas concentration sensor in a single unit box. SOLUTION: A plurality of detection holes are drilled with required intervals on the ground where leakage of a buried pipeline is suspected, and a suction hose 2 is inserted into the respective detection holes to operate a sucker 5. When retention gas fills under the ground, a valve body 32 of a switch valve 3 is removed to operate a sucker 5 with its suction capacity maximum for sucking the retention gas from all detection holes. Thereafter the valve body 32 is mounted on the valve 3, the valve body 32 is rotated to align a connection hole 33 sequentially with respective valve holes 3a to 3f for reducing the suction capacity of the sucker 5, and gas is sucked from each detection hole for each required time (3 to 5 seconds) for detecting 4 a gas concentration and displaying 6 it. Then the vicinity of the detection hole with the highest gas concentration is located as a gas leakage position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for specifying the location of a leak in a gas buried pipe from the ground.

[0002]

2. Description of the Related Art Conventionally, a method as shown in FIG. 3 has been adopted as means for specifying a leakage position of a buried pipe. As shown in the figure, first, a detection hole A, a detection hole B, a detection hole C, a detection hole D, and a detection hole E are bored with a required interval in the vicinity where leakage is considered to be occurring in the buried pipe P. .
Detectors a, b, c, each having a gas concentration sensor and a suction device in the detection holes A, B, C, D, and E, respectively.
d and e are inserted, the concentration is detected while sucking the gas in each of the detection holes, and is displayed on the gas concentration display f. Then, it is specified that there is a leak portion Q near the detection hole B where the gas concentration is the highest, and the leak portion 2 is repaired by excavating near the detection hole B.

Further, when a long time has elapsed after the occurrence of the leakage, the leakage gas fills the whole area in the ground, so that a high gas concentration is detected in all the detection holes, and it becomes difficult to specify the leakage position. Therefore, in this case, the detection holes A, B,
Insert a suction hose into C, D, and E to operate the suction pump, discharge the gas remaining in the detection hole, and then insert a detector into the detection hole to specify the leak position. I have.

[0004]

By the way, as a device configuration for specifying a leak position as described above, a plurality of detectors,
A plurality of cables, a plurality of suction hoses, a suction pump and a gas concentration indicator are required. Therefore, the equipment configuration becomes large and not only requires a great deal of labor to transport,
Since a plurality of expensive detectors having a gas concentration sensor and a suction device are required, a problem that the device becomes expensive is derived.

[0005] Each detector is provided with a gas concentration sensor. Therefore, when many tars and the like adhere to only a certain sensor due to long-term use and an error occurs in the accuracy of the sensor, a problem arises that it is difficult to accurately specify a leak position.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, an object of the present invention is to provide a device for specifying a leak position of a buried pipe which can specify an accurate leak position with a simple device configuration.

[0007]

In order to achieve the above-mentioned object, the present invention relates to a method of piercing a plurality of detection holes in a road surface, detecting and comparing the concentration of gas staying in the detection holes, and burying the detection holes in the road surface. In a leak position specifying device for a buried pipe for specifying a leak position of a pipe line, the device is provided in communication with a plurality of suction hoses for sucking gas in each detection hole and an upstream side of the hose, and each hose A switching valve for switching an inflow path from the valve, gas concentration measuring means provided upstream of the switching valve, and a suction device provided upstream of the gas concentration measuring means. is there.

Another feature is that the switching valve and the gas concentration measuring means are housed in a single unit box.

Another feature is that display means for displaying information from the gas concentration measuring means is provided.

[0010]

According to the leak position specifying device as described above, first, a plurality of detection holes are bored at predetermined intervals on the ground near where a leak is likely to occur. Then, a suction hose is inserted into the detection hole to operate the suction device. Here, when the ground is full of gas, the stagnant gas is discharged from each detection hole via a suction hose. After that, the switching valve is set in the first detection hole, the suction operation is performed for a required time, and the gas flowing through the valve is detected by the gas concentration measuring means. Next, the valve is set in the second detection hole, and a suction operation is performed to detect the gas concentration. By operating the valve in this manner, the gas concentration of the gas sucked from all the detection holes is detected. In addition, these operations are performed in a plurality of cycles as necessary, and the gas concentration is detected with higher accuracy. Then, the data is displayed on the display means, and the vicinity of the detection hole where the high gas concentration is detected is specified as the leak position.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of an apparatus for specifying a leak position of a buried pipe according to the present invention. FIG. 1 is a schematic explanatory diagram of a device configuration of a leak position specifying device 1 of the present invention.
As shown in the figure, the specific device 1 is provided so as to communicate with a plurality of suction hoses 2 for sucking gas in each detection hole formed by drilling a hole in the ground, and an upstream side of the hoses 2. Switching valve 3 for switching the inflow path from hose 2
A gas concentration sensor 4 provided on the upstream side of the switching valve 3, a suction device 5 provided on the upstream side of the gas concentration sensor, and a display device 6 for displaying information from the gas concentration sensor. ing.

The suction hose 2 is made of a material such as vinyl having flexibility, and a nozzle 21 is provided at a distal end thereof so as to be easily inserted into a detection hole. A filter (not shown) is provided inside the nozzle 21,
Prevents suction of earth and sand in the detection hole. The rear end of the suction hose 2 is communicated with a valve hole of a switching valve 3 described later.

In the switching valve 3, a plurality of valve holes 3a, 3b, 3c, 3d, 3e, 3f are opened along the circumference at the end face, and gas flowing from the opening communicates with the inside of the valve. Passages 3a ', 3b', 3c ', 3d', 3e ',
It is introduced through 3f ′, flows into the valve body chamber, and is discharged from the discharge port 31. A valve body 32 is detachably mounted in the valve body chamber. The valve body 32 is formed in a circular shape, and has a conduction hole 33 formed therein.
It is rotatably mounted in the valve 3. By rotating the valve body 32, the conduction hole 33 selectively coincides with the outlet of the communication passage, and the valve holes 3a, 3b, 3c, 3d, 3
It is configured such that it is possible to select which of the valve holes e and 3f performs the suction operation. Further, since the valve body 32 is detachable, when the valve body 32 is removed from the valve 3 and a sealing member is attached outside the valve 3, the valve holes 3a, 3b,
Suction is possible from all of 3c, 3d, 3e, and 3f.

A detection passage 41 communicates with the discharge port 31. A gas concentration sensor 4 is provided in the detection passage 41. The gas concentration sensor 4 detects the gas concentration of the gas flowing in the detection passage 41,
The detected information is transmitted to the display device 6 described later via the signal cable 42.

Here, the switching valve 3, the detection passage 41 and the gas concentration sensor 4 are housed in a single unit box as the distribution jig 7, and are configured to be easily carried. Although not shown, the switching valve 3
Is large (there is a large number of valve holes and the valve itself is large), a moving wheel may be attached to the distribution jig 7.

The suction device 5 has an explosion-proof function so that it does not explode even if the gas is sucked, and its suction port communicates with the detection passage 41. The suction device 5 has a function of adjusting the suction capacity.
The suction amount can be changed according to the situation.

The display device 6 has a built-in control mechanism such as a memory and a CPU, and has a function of organizing information transmitted from the gas concentration sensor 4 and displaying the information on a display unit such as a liquid crystal display in a graph or numerical value. Have.

Next, the operation of the leak position specifying device configured as described above will be described with reference to FIG. First, a detection hole A, B, C, D is formed by boring a hole at a required interval in the ground near the leaked point Q of the buried pipeline P. Next, the tip nozzle 21 of the suction hose 2 in the valve hole 3a is detected in the detection hole A, the tip nozzle 21 of the suction hose 2 in the valve hole 3b is detected in the detection hole B, and the tip nozzle 21 of the suction hose 2 in the valve hole 3c is detected. The tip nozzle 21 of the suction hose 2 of the valve hole 3d is inserted into the detection hole D into the hole C. When a long time has passed since the leakage occurred and the ground is full of gas, the valve element 32 of the switching valve 3
Is removed, and the suction device 5 is operated while maximizing the suction capacity,
A suction operation is performed from all the detection holes A, B, C, and D. Then, after performing the suction operation for the required time, the suction device is stopped.

After a lapse of the required time, the valve body 32 is mounted on the valve 3, and the valve body 32 is rotated to connect the conduction hole 33 to the valve hole 3a.
The suction operation is performed for a required time (3 to 5 seconds) by reducing the suction capacity of the suction device 5. Then, the gas concentration of the sucked gas is detected by a gas concentration sensor, and the data is transmitted to the display device 6. Next, the valve body 32 is rotated again so that the conduction hole 33 is aligned with the valve hole 3b, and a suction operation is performed to transmit the concentration data to the display device 6. Similarly, the gas concentration in the detection holes C and D is detected. These operations are performed for a plurality of cycles, and the average value of the respective density data in the detection holes A, B, C, and D is displayed on the display device 6. Then, the vicinity of the detection hole B where the highest concentration is obtained is specified as a leakage point.

In the present embodiment, the switching valve 3 is described using the rotary valve 32. However, the present invention is not limited to this, and a switching valve having another structure may be used.

[0021]

As described above, according to the apparatus for specifying the location of a leak in a buried pipe according to the present invention, since the equipment configuration is small, the labor for transportation and installation is reduced. In addition, since a single gas concentration measuring means is used, the cost of the entire apparatus is reduced. Also, unlike using a plurality of gas concentration measuring means, there is no error due to each measuring means. Can be constructed.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory diagram of a leak position specifying device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating the operation of the leak position specifying device according to the embodiment of the present invention.

FIG. 3 is an explanatory view of a conventional example.

[Explanation of Signs] 1 Leakage position specifying device 2 Suction hose 21 Nozzle 3 Switching valve 31 Outlet 32 Valve body 33 Conducting hole 4 Gas concentration sensor 41 Detection passage 42 Cable 5 Suction device 6 Display device 7 Distribution jig P Buried pipeline Q Leak location

Claims (3)

[Claims] 1. A leak position specifying device for a buried pipe for drilling a plurality of detection holes in a road surface and detecting and comparing the concentration of gas staying in the detection holes to specify a leak position of a pipe buried under the road surface. In the above device, the plurality of suction hoses for sucking gas in each detection hole, a switching valve provided in communication with an upstream side of the hose, and for switching an inflow path from each hose, and an upstream side of the switching valve And a suction device provided on the upstream side of the gas concentration measuring means. 2. The leak position specifying device for a buried pipe according to claim 1, wherein said switching valve and said gas concentration measuring means are housed in a single unit box. 3. The apparatus according to claim 1, further comprising display means for displaying information from said gas concentration measuring means.
2. The leak position specifying device for a buried pipe according to 2.