JP2015145804A - Water leak detection method of underground water pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for locating leakage of a water pipe embedded in the ground.SOLUTION: A guide rope 540 is inserted into a water pipe 110 installed in an underground water facility, and leakage detection means such as an acoustic sensor 600 and an underwater camera are mounted on this guide rope and inserted into the pipe. While moving the guide rope, sound inside the pipe is recorded by the acoustic sensor and an earphone 610 or directly heard, and/or a leak location is directly visually recognized from the inside of the pipe by the underground camera. The presence of the water leak can be determined by a physical property value of raw data free from statistical processing. The occurrence location of the water leak can be deduced from hearing water leak sound directly by the earphone, and/or a location at which a water leak phenomenon is directly visually recognized can be deduced from a distance of the guide rope sent out into the pipe. The method according to the present invention can easily investigate the water pipe such as a pipe line which is embedded in the ground and unable to be easily investigated from the outside in any of a water passing state or a water cut-off state.

Description

  The present invention relates to a method for detecting a water leak location of a water pipe buried underground, and more particularly to a method for detecting the water leak location simply and accurately by a water leak detection means carried on a guide rope.

  In order to effectively utilize existing facilities in the civil engineering and agricultural civil engineering fields, and to extend the service life, asset management that conducts appropriate maintenance management by investigating old structures rather than destroying and reconstructing old structures Is regarded as important. Asset management is a collective term for technical systems and management methods for effective use of existing facilities and extending their life through functional maintenance measures based on functional diagnosis of facilities. In recent years, many structures that have been rapidly developed during the high growth period have come to a renewal period as their useful lives elapse. Asset management for the purpose of establishing the maintenance technology will become more important in the future.

  Pipelines such as water supply and agricultural pipelines are underground in structure. Since it cannot be confirmed directly, the state of the facility cannot be grasped unless the water leakage is surfaced. In order to investigate the location of water leaks in pipes buried underground in this way, conventional methods such as humans entering the pipes to investigate deterioration, listening to the sound of water leaking from the road surface where pipes are buried, etc. Has been done by.

  There are the following problems in surveys in which humans enter and visually observe. It is necessary to drain the pipe in advance. In addition, humans cannot enter small-diameter pipes of 700 mmφ or smaller. In addition, a temporary facility for investigation is required on a large scale. There are also the following problems in the survey of hearing the leak sound of pipes buried under the road surface from the road surface. The accuracy of the interview survey depends on the magnitude of the leaked sound. The ability to tell whether or not there is a leaking sound requires considerable skill. If the buried position of the pipeline is too deep, it is very difficult to detect water leakage.

  In order to mechanize human work, investigation of sound waves recorded by sound wave sensors attached to pipe facilities, investigations using underwater self-propelled robots equipped with recorders, air self-propelled robots, or objects equipped with recorders Such methods are being studied and developed.

  The accuracy of the investigation using the acoustic wave sensor depends on the magnitude of the water leakage sound. If the sensor mounting position and the water leakage location are separated, water leakage detection becomes very difficult. If the sensor mounting interval is reduced in order to increase accuracy, the sensor installation cost increases. After the survey, advanced analysis including analysis of recorded data is required, and it takes days to confirm the abnormal part. In addition, in order to identify the location of water leakage, it is necessary to directly check as a water leakage phenomenon by conducting an excavation or drilling of an abnormal location.

  Patent Documents 1 to 6 disclose techniques related to a water pipe inspection robot using an underwater robot. The range of investigation by the underwater robot is limited to about 500 m at the maximum when the tube diameter is 800 mmφ or more, and about 50 m at the 700 mmφ or less. When a video or image is acquired by a recorder, earth and sand, dust, etc. accumulated in the pipe line are moved by the screw of the robot. Therefore, a clear image and video cannot be acquired, and it is very difficult to determine the presence or absence of water leakage in the pipeline.

  The investigation by the air robot needs to drain the pipe in advance. It is difficult to implement in steep pipelines. If the groundwater level is lower than the pipeline, it is difficult to identify the location of the water leak.

  There is known a system in which a recorder records water leakage while an object incorporating a recorder for examining the inside of a pipeline moves on the water flow in the pipeline. For example, the product name Smartball System (Toa Grout Co., Ltd.) inserts a sphere with a built-in sensor into the pipeline, and records the sound in the pipeline while the sphere moves through the pipeline. Go. The location of the water leakage is identified by receiving a pulse signal sent from the sphere at intervals of 3 seconds from the outside of the tube, calculating the distance based on the time difference at the time of reception, and further determining the water leakage location. This system requires advanced analysis technology for acoustic recording, and it takes days to determine. In addition, in order to identify the location of water leakage, it is necessary to directly check as a water leakage phenomenon by conducting an excavation or drilling of an abnormal location.

JP2007-911169A JP2009-244419 JP 2009-236876 A JP2009-244414 JP2009-235880 JP 2009-237498 A

  The development of a method that can easily investigate and diagnose the degree of aging and the presence or absence of defects in a water flow facility with a water pipe buried underground is desired. However, surveys cannot be conducted directly from the outside, and there are many implementation restrictions for surveys from the inside, and there is no established water leakage survey technology.

  An object of the present invention is to provide a method that is less susceptible to restrictions when conducting an internal investigation of an underground water pipe, and that allows an effective investigation to be easily performed. In particular, the present invention is a method that allows a leak sound to be heard directly from the inside of a water pipe at the time of investigation, or to visually recognize a leak phenomenon, to detect the leak phenomenon on the spot, and to perform reconfirmation easily and simply. I will provide a.

As a result of earnestly examining the above problems, the present inventor has found that the above problems can be solved by a method for identifying a water leak location using a guide rope installed in a water pipe, and has completed the present invention. That is, the present invention is a method for detecting leakage of underground water pipes, and includes the following steps:
(1) A first gate valve provided with a float insertion means and having a rubber-coated valve is installed on a sub-valve installed in a manhole on the upstream side of the detection range of the water pipe, and on the downstream side of the detection range After the second gate valve having the float recovery means and having the rubber-covered valve is installed on another sub valve installed in the manhole, the first and second sub valves are opened.
Here, the float insertion means and the float recovery means can be operated from the outside while maintaining the watertight state in the first and second gate valves, and the first and second gate valves are covered with the rubber-coated The valve can be opened and closed while maintaining a watertight state.
(2) After opening the first gate valve and inserting the float connected with the road thread by the float insertion means, the float is sent to the flow from upstream to downstream, the second gate valve is closed, and then the float is closed. Recover the float from the recovery means,
(3) Instead of the float collecting means, a second guide rope feeding mechanism having a function of feeding out the guide rope is attached to the second gate valve, and then the guide rope is connected to the end portion of the road yarn, The two gate valve is loosened, and the road yarn and the following guide rope are sent from the downstream side to the upstream side by the cooperative operation of the float insertion means and the second guide rope sending mechanism, and the road yarn is recovered from the downstream side, Complete installation of guide ropes in water pipes,
(4) In place of the float insertion means, a first guide rope sending mechanism having a function of sending out a guide rope is attached to the first gate valve, and then a water leakage detecting means is connected to the upstream guide rope, and the second or second Moving the water leakage detection means together with the guide rope in the direction of flowing water or in the opposite direction by pulling the guide rope from one guide rope sending mechanism;
(5) Let the water leakage detection means in motion detect the water leakage location,
(6) After the detection, the water leakage detection means is recovered by winding the guide rope from the first guide rope sending means, the guide rope is removed, and
(7) After closing the first and second auxiliary valves, removing the first and second guide rope sending means, and the first and second gate valves,
The method is provided.

  It is preferable that the water leak detection means is an acoustic sensor, an underwater camera, or an underwater camera with a listening function.

  The underground water pipe is, for example, a siphon or a pipeline.

  The first and second gate valves have a sufficient diameter to allow the float to pass when the valve is opened, and can maintain a watertight state with respect to the moving road line and the guide rope when the valve is closed. preferable.

  It is preferable that the float insertion means includes a float pushing casing that is moved up and down so as to be watertight, and a pair of rolls that feed the road yarn in a watertight manner.

  The float collecting means preferably includes a float collecting net having a float collecting net at the lower end and vertically moved so as to be watertight, and a pair of rolls for winding the road yarn in a watertight manner. .

  In step (2), it is preferable that the float collecting means includes an underwater camera, and the float is collected while capturing the arrival of the float with the underwater camera.

  The first and second guide rope sending means include a guide rope sending means including a pair of rolls that pull the end portions of the road thread extending from the first and second gate valves, and a road sandwiched between the rolls. It is preferable that a guide rope sandwiched between the rolls is fed into the gate valve so as to be watertight by providing a drum for winding the yarn and rotating the roll.

  According to the measurement principle of the present invention, a guide rope is passed through a water pipe installed in an underground water passage facility, and a water leak detection means such as an acoustic sensor or an underwater camera is attached to the guide rope and inserted into the pipe. And while moving a guide rope, the sound in a pipe | tube is recorded or heard directly with an acoustic sensor or an earphone, and / or a water leak location is directly visually recognized from the pipe | tube with an underwater camera. The presence or absence of water leakage can be determined from the physical property values of the raw data without statistical processing. The location of the water leakage can be identified by directly listening to the sound of the water leakage with the earphone and / or the position where the water leakage phenomenon is directly recognized by the distance of the guide rope that has been sent out. According to the method of the present invention, water pipes such as pipelines that are buried underground and cannot be easily investigated from the outside can be easily investigated in either a water flow state or a water flow stop state.

  In the conventional method of identifying the location of water leakage, analysis of the measurement record and diagnosis work are required after the investigation, and it takes a considerable number of days until the result is obtained. In addition, it was necessary to confirm the location of water leakage by trial drilling or drilling. In the present invention, it is possible to identify the location of the water leakage during the investigation by listening to the water leakage sound while conducting the investigation and visualizing the water leakage sound with a waveform or by directly visualizing the water leakage phenomenon.

  The method of this invention can catch a water leak location at a close distance by installing a guide rope. Therefore, the accuracy of specifying the water leakage location is significantly better than the conventional technology. Since the water leak detection means carried on the guide rope is easy to move upstream or downstream, it is possible to reconfirm the water leak location. Since water leakage sound and water leakage phenomenon are captured directly from the inside of the water pipe, there is no need for trial excavation and drilling work to confirm the presence or absence of the water leakage phenomenon. The detection method of the present invention can be implemented with a small number of people.

  The advantages of the present invention compared to prior art smartball systems are described below. Since the smart ball system moves while rolling, the rolling sound is recorded, and there is concern about the detection accuracy of the weak water leakage sound. In the present invention, since the water leakage detection means such as an acoustic sensor is connected to the guide rope and the acoustic sensor can be stopped, the detection environment and the detection accuracy are higher than the smart ball system in that no rolling noise is generated. It is good.

  The smart ball system collects the smart ball sensor and analyzes it to determine whether there is a leak or to check the location of the leak. take time. In addition, a confirmation survey (trial excavation and drilling work) is necessary to identify the location of water leakage. In the present invention, since the sound picked up by the abnormal point detection means and the video to be acquired are directly heard or viewed, the presence or absence of water leakage can be determined on the spot. Since the approximate position is known from the length of the guide rope that has been sent out, the location of the water leak can be identified on the spot. If the underwater camera visually observes the leak location, it will be easier to examine the repair method thereafter. Therefore, the method of the present invention is faster in analysis than the smart ball system.

  In order to perform measurement again with the smart ball system, the sensor is once taken out of the water pipe and inserted again from the upstream side for investigation. In the present invention, since the water leakage detection means such as the acoustic sensor is connected by the guide rope, the water leakage detection means such as the acoustic sensor is not collected from the inside of the pipe from upstream to downstream and from downstream to upstream. Therefore, the present invention requires less time for review as compared to the smart ball system.

  Since the progress speed of the smart ball depends on the flow velocity of the water pipe, it is difficult to predict the end time of the survey. Since there is no flow rate if water is not used, the sensor may stop. Sensor operation is impossible from the survey side. In the method of the present invention, the water leakage detection means such as an acoustic sensor is connected by a guide rope and can be operated on the investigation side. For this reason, the degree of freedom is higher than that of the smart ball system, for example, the survey time can be specified.

It is a figure explaining the operation | work for every step of the detection method according to this invention. The schematic sectional drawing of the water flow facility which the detection method of this invention makes object is shown. FIG. 3 is a cross-sectional view of a secondary valve installed on a pipeline rising pipe in an air valve chamber under a manhole at a point A and a point B in the pipeline of FIG. 2. It is sectional drawing of the state which installed the gate valve on the subvalve of FIG. (A) is the state which closed the rubber-coated valve, (B) is the state which opened the rubber-coated valve. Sectional drawing of the float insertion means installed on the gate valve of the A point of FIG. 4 is shown. Sectional drawing of the float collection | recovery means installed on the gate valve of the B point of FIG. 4 is shown. FIG. 7 shows how the float collecting means in FIG. 6 collects a float. (A) shows a state where a float is to be secured, (B) shows a state where the float has been collected, and (C) shows a state where the float collecting means has been removed. Sectional drawing of the guide rope sending mechanism installed on the gate valve of FIG. 4 is shown. The figure shows the guide rope delivery mechanism at point B, but the guide rope delivery mechanism at point A is similar. (A) is a sectional view of a guide roll delivery mechanism including a guide roll delivery means and a drum, (B) is an enlarged longitudinal sectional view of the guide rope delivery means of (A), and (C) is The expanded sectional view of a pair of roll is shown in the XX arrow of the guide rope sending means of (B). FIG. 4 shows a state where the gate valve at point A in FIG. 4 is closed, the guide rope sending means is opened, the acoustic sensor is installed on the guide rope, and the guide rope sending means is closed again. While the guide rope is wound up by the drum of the guide rope sending mechanism at point B, a state where the water leakage point is examined by the acoustic sensor is shown. An acoustic sound waveform acquired by the acoustic sensor at a water leakage point at a distance of 190 m from point A is monitored by a personal computer at point A.

  An embodiment of the detection method of the present invention will be described in detail with reference to the accompanying drawings. However, the following examples are illustrative and do not limit the present invention. FIG. 1 represents the steps of the detection method of the present invention.

(1) Installation of gate valve The water pipe targeted by the method of the present invention is not limited as long as it is buried underground in the fields of civil engineering, agricultural civil engineering, water supply and sewerage, and the pipe diameter, shape, length, etc. There is no particular limitation. Specific examples of water pipes include pipelines, siphons, water and sewage pipes, and the like.

  FIG. 2 shows a longitudinal sectional view of a water flow facility constituted by a water pipe buried underground, its riser pipe, and the like. In the water flow facility 100, manholes 130 are usually provided at intervals of about 400 m (points A to B in FIG. 2) so that workers can access from the ground. FIG. 3 shows a cross-sectional view of the manhole 130. Under the manhole 130 is an air valve chamber 140 of the pipeline 110. A rising pipe 150 (with a diameter of 75 to 200 mmφ) branches from the pipeline 110, and a secondary valve 160 is installed at the top end of the rising pipe. The worker accesses the pipeline 110 through the auxiliary valve and the riser pipe.

  When carrying out the method of the present invention, the pipeline 110 is filled with water in both the water flow state and the water stop state, and is always under pressure. The sub-valve 160 does not have a function of taking out and inserting jigs having different diameters such as a float insertion means, a float recovery means, a road thread and a guide rope, which will be described later, while maintaining a watertight state. Therefore, in order to use the jig in a watertight state, the dedicated gate valve 200 is installed on the auxiliary valve 160. The first gate valve 200 on the auxiliary valve installed in the manhole (point A) on the upstream side of the detection range of the water pipe, and the auxiliary valve installed in the manhole (point B) on the downstream side of the detection range of the water pipe A second gate valve 200 is installed on the valve. The installation state of the gate valve is shown in FIG.

  The 1st and 2nd gate valve 200 has the pipe body 210 which has the rubber-coated valve 230 which adjusts the aperture | diameter in a pipe | tube inside. The inner diameter of the tube body is a size that allows free entry and exit of a float, float insertion means, etc., which will be described later, and is usually 75 to 200 mmφ as in the riser tube.

  The sub-valve 160 cannot adjust the opening diameter while maintaining a watertight state. On the other hand, in the present invention, the rubber-coated valve 230 having elasticity by the rubber coating 231 at the tip can always be sealed in a state where a road thread and a guide rope described later are sandwiched. The opening diameter of the gate valve 200 is adjusted by, for example, putting in and out the rubber-coated valve 230 as shown in FIGS. 4 (A) and 4 (B). Therefore, as shown in FIG. 4B, a valve housing chamber 220 having a space that can accommodate the rubber-coated valve 230 is provided on the side surface of the tubular body of the gate valve. When the gate valve is opened, the valve retracted from the tubular body is accommodated in the accommodation chamber.

  The rubber-coated valve 230 is moved by rotating a rod body 240 attached to the side of the rubber-coated valve and having a threaded structure through a screw hole provided in the valve housing chamber 220. The screw hole of the valve housing chamber is sealed so as to maintain a watertight state even by the movement of the rod body.

  The first and second gate valves 200 have flanges 250 on the bottom surface of the pipe body 210 that enable coupling with the sub valves. The gate valve 200 also has a flange 250 on the upper surface of the pipe that enables coupling with a float insertion means, a float recovery means, and a guide rope delivery means, which will be described later.

  After the first and second gate valves are installed on the first and second auxiliary valves, respectively, the first and second auxiliary valves are opened. Thereby, the transfer from the sub valve 160 to the gate valve 200 is completed.

(2) Float Insertion and Recovery A float 310 shown in FIG. 5 is a floating body that is used to pass the road thread 370 from point A to point B and is movable along the water flow of the water pipe. The shape of the float 310 is not particularly limited as long as it can pass through the gate valve. As shown in the figure, a tapered and wide shape is preferable in that it breaks up the water flow and easily rides the flow.

  A float insertion means 300 shown in FIG. 5 is attached on the first gate valve 200 at the point A. The float insertion means 300 can be operated from the outside while maintaining the watertight state in the first gate valve. For this purpose, the float insertion means has a tubular body 320 directly connected to the upper flange 250 of the first gate valve as its housing. A hole having a seal structure is provided in the center of the top plate of the tube body 320, and the float pushing housing 330 passes through the hole. A face body 340 for pushing the float is attached to the lower end of the housing 330.

  A roll housing chamber 360 that houses a pair of rolls 350 that guide the road yarn 370 coupled to the float 310 is provided on the side surface of the tube body 320. The road yarn 370 sandwiched between the rolls is fed out from a drum 380 installed outside the manhole.

  A float collecting means 400 shown in FIG. 6 is installed on the second gate valve 200 at the point B. The float collecting means 400 can be operated from the outside while maintaining the watertight state in the second gate valve 200. Therefore, the float collection | recovery means 400 has the shape of the pipe body 410 directly connected to the upper flange of a 2nd gate valve. A hole having a sealing structure is provided at the center of the top plate of the tube body, and the float recovery housing 420 passes through the hole. A net 430 for collecting the float 310 is attached to the lower end of the housing 420.

  In order to confirm that the float 310 has arrived from upstream, an underwater camera 440 is attached near the net 430. Visual information from the underwater camera is sent to a monitor 450 installed outside the manhole in a wired or wireless manner.

  As shown in FIG. 5, the first gate valve 200 is opened at the point A, and the float 310 with the road thread 370 is inserted by the float insertion means 300. The material of the road thread should have lightness that does not hinder the swimming of the float and tensile strength that does not break. Specific examples include polyvinylidene fluoride, fluorocarbon, polyethylene, polyamide resin (for example, trade name nylon, Zylon (registered trademark)), and the like.

  The float 310 travels from the point A to the point B on the water flow in the pipeline with the road line attached. The underwater camera 440 at point B confirms the arrival of the float. When the float 310 comes close to the point B, as shown in FIG. 7A, the float collecting means 420 is lowered into the pipeline, and the float 310 is secured in the network 430. Next, as shown in FIG. 7B, the net 430 in which the float 310 is secured is pulled up into the tube 410 and the second gate valve 200 is closed. Next, as shown in FIG. 7C, the float collecting means 400 is removed. Remove the float 310 at the end of the thread.

(3) Guide rope installation At point B, instead of the float collecting means 400, a second guide rope sending mechanism 500 for taking in and out the guide rope is installed. This mechanism includes a guide rope sending means 520 including a pair of rolls 510 sandwiching an end portion of a road thread extending from the second gate valve 200, and a drum 530 around which a guide rope connected to the road thread sandwiched between the rolls is wound. Prepare. The roll and drum have a take-up handle. At point B, the end of the road thread 370 and the guide rope 540 of the drum are connected (FIG. 8). The material of the guide rope is not particularly limited. The thickness of the guide rope 540 should just have the rigidity which can hold | maintain the water leak detection means mentioned later, and is 5-30 mmphi normally.

  The first and second gate valves 200 are loosened, and the road thread 370 is wound up by the float insertion means 300 at the point A. On the other hand, the guide rope 540 connected to the road line 370 is sent out by the second guide rope sending mechanism 500 at the point B. By the cooperative operation of the float insertion means 300 and the second guide rope sending mechanism 500, the road thread 370 and the guide rope 540 that follows the thread 370 are passed from the point B to the point A. When the tip of the guide rope 540 reaches the point A, the guide rope feeding at the point B is finished. This completes the installation of the guide rope in the pipeline between the points A and B.

(4) Insertion of Water Leakage Location Detection Means Instead of the float insertion means 300 at point A, a first guide rope sending mechanism 500 for installing and removing the guide rope into and from the gate valve is installed. This mechanism includes a guide rope sending means 520 including a pair of rolls 510 that pulls the end portion of the road yarn 370 extending from the first gate valve, and a drum 530 that winds up the road yarn sandwiched between the rolls. The roll and drum are appropriately equipped with a take-up handle and a distance meter for measuring the length of the guide rope sent out.

  A water leakage detecting means is connected to the guide rope 540 at the point A or the point B, preferably the point A. The water leakage detection means is not particularly limited as long as it can be used in water and has a function of detecting a water leakage location. Examples include acoustic sensors and underwater cameras. Acoustic sensors that can be used in water are commercially available as product hydrophones. These commercially available hydrosensors can be used in the method of the present invention. An underwater camera with a listening function is particularly preferable.

  The acoustic sensor 600 exemplified as the water leak detection means in FIGS. 9 and 10 picks up a water leak sound when approaching the water leak point, particularly preferably a sensor with an amplifier function for amplifying the picked water leak sound, or a waveform of the water leak sound. It has a function to transmit information on the location of water leakage to the outside wirelessly or by wire.

  The water leak sound and the waveform acquired by the acoustic sensor 600 can be listened to by a site worker at the site (point A or point B) with headphones or earphones, or monitored with an oscillograph or the like.

(5) Detection Work As shown in FIG. 10, the acoustic sensor 600 is moved by pulling the guide rope 540 with the guide rope sending mechanism 500 at the point B. The acoustic sensor 600 can be moved in the direction opposite to the flowing water direction by pulling the guide rope 540 from the guide rope sending mechanism 500 at the point A.

  While the acoustic sensor 600 is guided from the point A to the point B, the acoustic sensor is caused to perform a detection operation of the water leakage point 120 (distance of 190 m from the point A in the drawing). The method of the present invention can be carried out with or without water flow. Since there is a possibility that the acoustic sensor 600 picks up the water-passing sound when water is passed, it is preferable that water is not passed during detection work.

  As shown in FIG. 10, the water leakage sound information from the acoustic sensor 600 is heard directly from the earphone or the headphone 610 at the point A (or point B) or visualized on the monitor 620. Note that the water leakage sound and its waveform are appropriately stored in a recorder or a computer (not shown).

  When the site worker operates the guide rope 540, the acoustic sensor 600 approaches or is far from the water leak location 120. The site worker can intuitively confirm the location of the water leakage based on the perspective of the water leakage sound at that time. In addition, since the guide rope 540 can easily move upstream and downstream, it is also easy to remeasure the water leak location 120. Thus, the present method for judging the presence or absence of water leakage by listening to the water leakage sound or by looking at the waveform thereof is simple and accurate.

(6) Guide rope recovery After detection, the acoustic sensor 600 guided to the B point is recovered at the B point. The guide rope is collected by winding the guide rope 540 with the first guide roll delivery mechanism at point A or the second guide roll delivery mechanism at point B, preferably the first guide roll delivery mechanism at point A.

(7) Removal of gate valve The first and second auxiliary valves 160 are closed, the first and second guide rope delivery mechanisms 500 are removed, and finally the first and second gate valves 200 are removed.

100 Water flow facility 110 Pipe line (water pipe)
120 Water leakage point 130 Manhole 140 Air valve chamber 150 Rise pipe 160 Sub valve 200 First and second gate valve 210 Tubular body 220 Rubber-coated valve housing chamber 230 Rubber-coated valve 231 Rubber-coated 240 Rod body 250 Flange 300 Float insertion means 310 Float 320 Tubular 330 Float pushing housing 340 Face body 350 Roll 360 Roll storage chamber 370 Road thread 380 Drum 400 Float collection means 410 Tubing 420 Float collection housing 430 Net 440 Underwater camera 450 Monitor 500 First and second guides Rope delivery mechanism 510 Roll 520 Guide rope delivery means 530 Drum 540 Guide rope 600 Acoustic sensor (water leakage detection means)
610 Earphone or headphone 620 Monitor

Claims (8)

A method for detecting leakage of underground water pipes, the following steps:
(1) A first gate valve provided with a float insertion means and having a rubber-covered valve is installed on the first subvalve installed in the manhole on the upstream side of the detection range of the water pipe, and downstream of the detection range On the other subvalve installed in the side manhole, the first and second subvalves are opened after the second gate valve having the float recovery means and having the rubber-coated valve is installed,
Here, the float insertion means and the float recovery means can be operated from the outside while maintaining the watertight state in the first and second gate valves, and the first and second gate valves are covered with the rubber-coated The valve can be opened and closed while maintaining a watertight state.
(2) After opening the first gate valve and inserting the float connected with the road thread by the float insertion means, the float is sent to the flow from upstream to downstream, the second gate valve is closed, and then the float is closed. Recover the float from the recovery means,
(3) Instead of the float collecting means, a second guide rope feeding mechanism having a function of feeding out the guide rope is attached to the second gate valve, and then the guide rope is connected to the end portion of the road yarn, The two gate valve is loosened, and the road yarn and the following guide rope are sent from the downstream side to the upstream side in cooperation with the float insertion means and the second guide rope delivery mechanism, and the road yarn is recovered from the upstream side, Complete installation of guide ropes in water pipes,
(4) In place of the float insertion means, a first guide rope sending mechanism having a function of sending out a guide rope is attached to the first gate valve, and then a water leakage detecting means is connected to the upstream guide rope, and the second or second Moving the water leakage detection means together with the guide rope in the direction of flowing water or in the opposite direction by pulling the guide rope from one guide rope sending mechanism;
(5) Let the water leakage detection means in motion detect the water leakage location,
(6) After the detection, the water leakage detection means is collected by winding the guide rope from the first or second guide rope sending mechanism, and the guide rope is removed; and
(7) After closing the first and second auxiliary valves, removing the first and second guide rope delivery mechanisms and the first and second gate valves;
Said method.   The method according to claim 1, wherein the water leakage detection means comprises an acoustic sensor, an underwater camera, or an underwater camera with a listening function.   The method according to claim 1 or 2, wherein the underground water pipe is a siphon or a pipeline.   The first and second gate valves have a caliber sufficient to pass a float when the valve is opened, and maintain a watertight state with respect to the moving road line and the guide rope when the valve is closed. The method according to any one of claims 1 to 3.   The said float insertion means is a method as described in any one of Claims 1-4 which comprises the pair of rolls which send out the float-pushing housing | casing which can be moved up and down so that it can be watertight, and a road thread so that watertightness is possible.   The float collecting means includes a float collecting net that has a float collecting net at the lower end and is movable up and down in a watertight manner, and a pair of rolls that wind up the road yarn in a watertight manner. The method as described in any one of 1-5.   In step (2), the float collecting means includes an underwater camera, and the float is collected while capturing the arrival of the float with the underwater camera. Method.   The first and second guide rope delivery mechanisms each include a guide rope delivery means including a pair of rolls that pull between the ends of the road yarn extending from the first and second gate valves, and a road sandwiched between the rolls. The drum according to any one of claims 1 to 7, wherein the guide rope sandwiched between the rolls is fed into the gate valve in a watertight manner by rotating the roll and having a drum for winding the yarn. Method.