JP2018189411A - Leak detection method and leak detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce noise generation and to detect leakage and its position in a pipe by moving a body along the approximate center of the pipe through which pressurized liquid flows.SOLUTION: In the leak detection method, a movable body 1 is moved together with liquid along an approximate center of a pipe B. The movable body is configured so as to collect and record the sound transmitted through the liquid when a pressurized liquid flows through the pipe and to detect its movement position in the pipe. From the data of sound transmitted through the liquid and recorded during the movement of the movable body and the detected movement position of the movable body in the pipe, a leakage position in the pipe is detected. The leakage detector A has the movable body 1 that is arranged with: a sound collection member 10 whose outside diameter is smaller than an inner diameter of a pipe and which collects sound transmitted through the liquid; a recording member 11 for recording the collected sound; and a position detection member 12 for detecting the movement position, and that moves together with the liquid. The specific gravity of the moving body is substantially the same as that of the flowing liquid.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a method and an apparatus for detecting the presence / absence of a leak in a pipeline through which a liquid having a pressure flows and a leak position.

  Pipes are laid in the ground through which liquids having various pressures, including water supply, industrial water, and agricultural water, circulate. In such a pipe line, pipes of standard size are arranged in series and a joint having a structure corresponding to the flowing liquid is configured to connect the pipes while ensuring liquid tightness. . For example, in the case of a pipeline for industrial water or agricultural water, water tightness is ensured by connecting pipe ends of fume pipes through packing. Moreover, in the case of a pipe for waterworks, watertightness is ensured by fastening bolt ends of the cast iron pipes with packing.

  On the other hand, the pipe laid in the ground intersects with the force according to the vibration by the vehicle traveling on the road surface, the force accompanying the ground subsidence, the laying direction of the pipe line in the event of an earthquake or the laying direction of the pipe line. Forces such as force in the direction are always acting. Then, these forces acting on the pipe line may cause a gap between the pipe joints to form a gap or a crack in the pipe wall.

  When gaps in the joints, cracks in the pipe wall, etc. occur in the pipe line through which the liquid with pressure flows, the liquid in circulation leaks into the ground, resulting in a problem corresponding to the nature of the liquid flowing. For example, in the case of industrial water, agricultural water, or clean water, these waters are subjected to water treatments according to their respective purposes, and waste of water costs due to water leakage. Moreover, there is a possibility that the ground around the pipeline may be softened or the soil may be changed due to water leakage from the pipeline.

  In order to deal with the problems as described above, the presence or absence of water leakage and the location of water leakage in pipes laid in the ground are investigated. Such a survey is generally performed by detecting an audible sound generated due to water leakage from the pipeline. That is, an audible sound generated when a liquid having a pressure is ejected from a gap formed in a joint between pipes or a crack formed in a pipe wall, a valve such as a gate valve or a water faucet formed in the pipe line. It is possible to determine whether or not water has leaked in the surveyed pipe line, and the position of the water leak by using a sound sensor that has been moved along the pipe line. is investigating.

  The present applicant has developed a “leak detection device and leak detection method” described in Patent Document 1 and has obtained a patent right. In this technique, a moving body equipped with a sound collecting member, a recording member, and a member for detecting a position in the pipe is moved in the pipe through which the pressure fluid flows, so that the fluid flows through the pipe. In addition, the leaking part is detected by collecting and recording the sound generated at the same time and detecting the position.

Japanese Patent No. 5583994

  In the invention described in Patent Document 1, the moving body moves along the bottom of the pipe along with the flow of the pressure fluid, and collects and records the sound during this moving process. For this reason, the outer peripheral surface of the moving body comes into contact with the bottom surface of the pipeline, and an impact sound is generated. In addition, the moving speed of the moving body becomes slower than the flow velocity of the fluid, and scratching noise is generated when the fluid passes through the outer peripheral surface of the moving body. Any sound generated in this manner is collected by the sound collecting member mounted on the moving body and recorded on the recording member.

  As described above, the impact sound generated when the moving body comes into contact with the bottom surface of the pipe line and the rubbing sound generated due to the difference between the moving speed of the moving body and the flow velocity of the fluid are all noises for leakage detection. . For this reason, it is necessary to separate noise and leakage sound from the recorded sound, and this separation work has a problem of requiring high skill.

  In addition, since the moving body moves along the bottom surface of the pipe line (position displaced from the center of the pipe line), the collected sound may be generated by the interference from the wall surface of the pipe line. In this case, it may be difficult to detect an accurate water leakage position in the pipe.

  It is an object of the present invention to reduce the occurrence of noise by moving a moving body along substantially the center of a pipeline through which a liquid having pressure flows, and to detect the presence or absence of a pipeline and the leakage position. It is in providing the detection method and the leak detection apparatus which enforces this method.

  In order to solve the above problems, a leak detection method according to the present invention is a leak detection method for detecting a leak in a pipeline through which a liquid with pressure flows, and when a liquid with pressure flows. A moving body configured to collect and record the sound transmitted through the liquid and to detect a moving position in the pipe, and the liquid flowing through the pipe, is substantially at the center of the pipe. In the pipeline by the sound data of the sound transmitted through the liquid recorded in the moving process of the moving body and the detected moving position in the pipe of the moving body. The leak position is detected.

  The first leak detection device according to the present invention is a leak detection device for detecting a leak in a pipeline through which a liquid having a pressure flows, the outer diameter being smaller than the inner diameter of the pipeline, and Inside, a sound collecting member for collecting the sound transmitted through the liquid when the liquid flows through the pipe, a recording member for recording the sound collected by the sound collecting member, A position detecting member for detecting the moving position of the moving body, and a moving body that moves together with the liquid in the pipe line, and the specific gravity of the moving body is substantially the same as the specific gravity of the flowing liquid It is characterized by this.

  Furthermore, the second leak detection device according to the present invention is a leak detection device for detecting a leak in a pipeline through which a liquid having a pressure flows, the outer diameter being smaller than the inner diameter of the pipeline, and Inside, a sound collecting member for collecting the sound transmitted through the liquid when the liquid flows through the pipe, a recording member for recording the sound collected by the sound collecting member, A position detecting member for detecting a moving position in the pipe and a moving body that moves together with the liquid in the pipe line, and the moving body has a specific gravity slightly smaller than the specific gravity of the liquid. The movable body is provided with a specific gravity adjusting member that is flexible and has a length that allows the end portion to contact the bottom of the pipe.

  In any one of the above leakage detection devices, the moving body is preferably formed as a cylindrical body.

  Further, in any one of the above leakage detection apparatuses, the member for detecting the movement position in the pipeline of the moving body is configured to have a gyro and an acceleration sensor mounted on the moving body. It is preferable.

  In any one of the above leakage detection apparatuses, a member for detecting a movement position in the pipeline of the moving body is equipped with a pulse signal corresponding to a reference clock mounted on the moving body. A pipe to be detected, comprising: a transmitting member for transmitting; and a receiving member that is provided outside the pipe for detecting leakage and receives a pulse signal transmitted from the transmitting member in synchronization with the clock of the transmitting member. The moving position of the moving body in the pipe line is determined by the time difference when the receiving member receives the pulse signal transmitted from the transmitting member moving inside the road and the receiving member receives the pulse signal transmitted from the transmitting member. It is preferable that it is comprised so that can be detected.

  The leakage detection method according to the present invention is a method for detecting leakage in a pipeline through which a liquid having pressure (hereinafter simply referred to as “liquid”) flows. In this water leakage detection method, the moving body is moved along the approximate center of the pipe along with the flowing liquid, and the sound transmitted through the liquid is collected and recorded, and the moving position in the pipe is determined. Detect. And the presence and position of water leakage are detected by matching the sound data of the recorded sound with the position of the moving body.

  In particular, the moving body does not come into contact with the wall surface including the bottom of the pipe line because the moving body moves along the approximate center of the pipe line. For this reason, there is no risk of noise due to contact with the pipe wall accompanying the movement of the moving body, and the sound generated in any of the pipes interferes with other parts in the pipes. There is no risk of noise. Therefore, only sound due to water leakage can be recorded, and accurate water leakage detection can be realized.

  Further, in the first leak detection device according to the present invention, the specific gravity of the movable body in which the sound collecting member, the recording member, and the position detection member are disposed is substantially the same as the specific gravity of the liquid. It can move with the liquid along the approximate center of the path.

  In particular, when the liquid flowing through the pipe line is maintained in a laminar flow state, when the moving body is displaced from the center of the pipe line, the flow velocity of the liquid along the outer peripheral surface of the moving body is reduced to the center side of the pipe line. And on the tube wall side. For this reason, when a moving body contacts the liquid of the different flow velocity, the force to the center side of a pipe line acts, As a result, the position of the approximate center of a pipe line can be hold | maintained.

  Further, in the second leak detection device according to the present invention, the moving body in which the sound collecting member, the recording member, and the position detection member are disposed has a specific gravity slightly smaller than the specific gravity of the liquid. A specific gravity adjusting member is provided on the outer peripheral surface. Therefore, the difference between the specific gravity of the liquid and the specific gravity of the moving body can be adjusted by the specific gravity adjusting member, and the moving body can be moved together with the liquid flowing along the approximate center of the pipe line.

  Further, in any one of the above leakage detection apparatuses, when the position detection member for detecting the movement position of the moving body includes a gyro and an acceleration sensor mounted on the moving body, It is possible to detect its own movement position in the process of moving in the pipeline along with the liquid.

  In any one of the above leakage detection apparatuses, a position detection member for detecting the movement position of the moving body is provided outside the pipe line, and a transmission member that transmits a pulse signal mounted on the moving body. And a receiving member that receives the pulse signal transmitted from the transmitting member, the receiving member receives the pulse signal transmitted from the transmitting member that moves inside the pipe, and the pulse signal transmitted from the transmitting member is The moving position in the pipe of the moving body can be detected by the time difference when received by the receiving member.

  Therefore, in any one of the above leakage detection apparatuses, the sound that is generated in the pipeline and transmitted through the liquid is collected by the sound collection member in the process in which the moving body moves along the approximate center of the pipeline, The collected sound can be recorded on the recording member. Furthermore, the moving position of the moving body in the pipe line can be detected by the position detecting member. For this reason, the presence / absence and position of water leakage can be detected by matching the sound collected by collecting the moving body from the pipe and the detected movement position in the pipe.

It is a schematic diagram explaining the leak detection method which concerns on this invention. It is a schematic diagram explaining the structure of the leak detection apparatus which concerns on 1st Example. It is a figure explaining the movement state of the leak detection apparatus which concerns on 1st Example. It is a schematic diagram explaining the structure of the leak detection apparatus which concerns on 2nd Example. It is a figure explaining the example of the method of detecting the movement position in the pipe line of a mobile body.

  Hereinafter, the leakage detection method according to the present invention will be described. The leak detection method according to the present invention is for detecting the presence / absence of a leak in a pipeline through which liquid flows and the position of the leak when it occurs.

  The leakage detection method according to the present invention will be described with reference to FIG. In the present invention, as will be described later, when the liquid flows, the moving body constituting the leak detection device A that collects and records the sound transmitted through the liquid and detects the moving position in the pipe line 1 is moved along the approximate center of the pipe B. For this reason, the moving body 1 does not contact the bottom surface of the pipe B, and it is possible to eliminate the sound generated in such a case. Further, since the moving body 1 moves along substantially the center of the pipe B, the sound generated from the pipe wall due to leakage is directly collected via the liquid, that is, the sound before the interference is collected. It is possible to make a sound.

  Here, the approximate center of the pipeline B means that it does not have to exactly coincide with the center Ba of the pipeline B, and the range displaced from the center Ba is not limited numerically. That is, the movable body 1 does not come into contact with the bottom surface or the side surface of the pipe B, and it means a range in which sound due to leakage does not interfere.

  Then, after the moving body 1 moves through the target section in the pipe, the sound data of the sound collected and stored is matched with the moving position of the moving body 1 in the pipe B. It is possible to detect the presence or absence of leakage in the pipeline B and the position of the leakage in the case of leakage.

  That is, the sound transmitted through the liquid to the moving body moving through the pipe line includes water leak sound generated when the liquid leaks from the pipe line, scratching sound generated when the liquid contacts the pipe wall, and liquid. Sound generated when passing through the water control valve, sound generated when air accumulated inside the pipe leaks from the air valve, and rubbing sound with liquid generated when the moving body moves in the pipe There are contact sounds generated when the moving body comes into contact with the pipe wall, sounds outside the pipe line transmitted to the pipe line through the soil, and further transmitted through the liquid.

  The various sounds described above are collected and stored. And it is possible to analyze the stored sound data, extract the sound data of the water leak sound, and process the sound data other than the water leak sound as noise.

  In the present embodiment, the pipe B indicates a pipe for waterworks, and is configured by arranging a plurality of cast iron pipes 20 in series and connecting them using bolts and nuts via packing (not shown). ing. However, the leak detection method according to the present invention is not applied only to the pipe for water supply, such as a pipe through which a liquid having pressure flows, such as an industrial water pipe, an agricultural water pipe, etc. Of course, it is possible to apply to a pipeline.

  Further, it is assumed that the leaking portion 25 including a crack exists in the pipe line B.

  The pipe B as described above is provided with a valve plug C having a valve for releasing air mixed in the pipe B at an appropriate interval, a valve for closing the pipe B, or a valve 18 such as a fire hydrant. Therefore, when detecting a leak in the pipeline B, it is common to work using the valve plug C, and upstream of a section in the pipeline B where a preset leak is to be detected. The movable body 1 is inserted from the valve plug portion C of FIG. 2, and the movable body 1 is discharged from the downstream valve plug portion C.

  Therefore, the distance between the upstream valve plug portion C and the downstream valve plug portion C is the length of the pipeline B where leakage should be detected. However, the distance between the valve plug C for inserting the moving body 1 and the valve plug C for discharging the moving body 1 is not limited, and can range from several hundred m to several kilometers.

  Here, the tendency of the sound generated inside the pipe B will be described. In the portion of the pipeline B where there is no water leakage, only the sound generated when the clean water flows through the pipeline B is generated. This sound is a rubbing sound with respect to the circulating cast iron pipe 20 of the flowing water and a rubbing sound with respect to the moving body 1 of the drinking water, and the level of the sound data (hereinafter simply referred to as “sound level”) is substantially constant.

  Moreover, in the leaking part 25, the peculiar sound which is emitted when clean water ejects from the cast iron pipe 20 to the ground is generated. This sound becomes maximum at the leaking portion 25 and decreases as the distance from the leaking portion 25 increases. For this reason, the sound level is a relatively sharp triangle, and the height of the triangle and the size of the skirt are proportional to the amount of leakage.

  A procedure for detecting leakage in the pipe B having the leakage portion 25 as described above will be described.

  First, the two valve plugs C provided in the pipe B are selected, and the movable body 1 constituting the leak detection device A is connected to the valve plug C installed on the upstream side, and the mobile 1 is connected to the pipe An insertion member 21 for insertion into B is prepared, and a collection member 22 for collecting the moving body 1 that has moved through the conduit B is prepared at the downstream valve plug portion C.

  Next, after the moving body 1 is gripped by the distal end portion of the insertion device 21, the insertion device 21 is inserted into the conduit B through the valve plug portion C on the upstream side of the conduit B. In this state, the moving body 1 starts collecting sound on the basis of the elapsed time, starts recording sound, and starts detecting the moving position. Further, there is no leakage from the valve plug C when the collection member 22 is inserted into the valve plug C on the downstream side and the net-shaped collection unit provided at the tip reaches the inside of the pipe B. Keep it like that. Thereby, the preparation for detecting the leakage of the pipe B between the valve plug C on the most upstream side and the valve plug C on the most downstream side is completed.

  Next, when the gripping of the moving body 1 is released by operating the insertion member 21, the moving body 1 becomes free in the pipeline B, receives the velocity energy of the clean water flowing through the pipeline B, and receives the pipeline It moves downstream along the approximate center of B. In the process in which the moving body 1 moves along the center of the pipe B, the sound of clean water flowing through the pipe B is collected and recorded as sound data, and the moving position is detected and stored. .

  When the moving body 1 is collected by the collecting member 22 arranged in the valve plug portion C on the most downstream side, the collecting member 22 is pulled up. At this time, it is preferable to keep the state where the moving body 1 is collected by the collecting member 22, cause artificial water leakage at the valve plug C, and record the generated sound.

  The sound level recorded by this artificial water leakage becomes a magnitude corresponding to the amount of water leakage, and the shape of the sound level line is a sharply projected triangle. And the flow rate to be artificially leaked is about three types, small, medium and large, and by recording the sound generated at the time of each leakage, from about three types of different sound data corresponding to each leakage amount It is possible to record a level line.

  Next, the sound recorded by the moving body 1 pulled up from the pipe B and the moving position are compared. That is, the sound level line 30 with respect to the extension direction of the pipe line B (position of the moving body 1) is obtained by matching the recorded sound with the position of the moving body 1 on the basis of the time axis common to both. It becomes possible to make it correspond.

  Then, the sound level line 30 and the extension direction of the pipe line B are made to correspond to each other, and the change part of the sound level in the sound level line 30 is examined, so that it is estimated what state the change part is in. For example, the portion 31 is generated at the beginning, middle, and end of the sound level line 30 and is not a loud sound. Therefore, it can be estimated that the portion 31 corresponds to the valve plug portion C.

  Further, the portion 32 has a substantially linear sound level, and it can be estimated that there is no special failure in the pipe line B.

  The sound level of the portion 33 is a triangle with a sharp tip. It can be assumed that the portion 33 is clearly in an abnormal state and that the leaking portion 25 exists in the pipeline B corresponding to the apex of the portion 33. Further, the leakage at the leakage portion 25 is compared by comparing the shape of the sound level line corresponding to each flow rate when the leakage is made artificially at the valve plug portion C on the most downstream side with the shape of the portion 33. The amount can be estimated.

  Next, the configuration of the leak detection apparatus according to the present invention will be described. In the present invention, the moving body 1 constituting the leak detection device A moves along the approximate center of the pipe B together with the liquid flowing through the pipe B. However, the configuration of the moving body 1 that moves along the approximate center of the pipe B is not particularly limited, and a relationship with the specific gravity of the liquid may be set.

  For example, the moving body 1 can be moved along the approximate center of the pipe B by setting the specific gravity to be substantially the same as the specific gravity of the liquid. In this case, it is preferable that the liquid flowing through the pipe line B maintains a laminar flow state. In addition, the movable body 1 can be moved along substantially the center of the pipe B by setting the specific gravity to be slightly smaller than the specific gravity of the liquid and attaching a specific gravity adjusting member to the outer periphery.

  The shape of the moving body 1 is not particularly limited, and is preferably a cylindrical body having a length capable of accommodating each member to be disposed inside, or a cylindrical body having a substantially circular cross section. In the case of such a cylindrical body, the shape of the front and rear ends is preferably spherical. Further, although the size is not limited, it is necessary to have an outer diameter that is sufficiently smaller than the inner diameter of the target pipe B, and to be a dimension that can easily pass through the valve plug portion C. It is. Since the pipe constituting the valve plug C normally has a diameter of 75 mm, the outer diameter of the moving body 1 is preferably about 50 mm to 70 mm. Although the length corresponds to the configuration of the member to be accommodated, it is preferably about 100 mm to about 150 mm.

  In particular, in order to stabilize the posture of the moving body 1 when moving inside the pipe B, it is preferable to arrange the members accommodated therein so that the weight is concentrated in the low part. By arranging in this way, it is possible to reduce rolling that may occur during movement.

  Further, when the moving body 1 moves in the horizontal bent portion of the pipe B, a force is applied to rotate the moving body 1 in the horizontal direction. In order to counteract this force, it is preferable that the weight of the moving body 1 be configured to be distributed at both front and rear ends. By configuring in this way, it becomes easy to suppress yawing.

  Therefore, it is preferable that the moving body 1 is a cylindrical body having an appropriate length and configured so that the weight acts on both front and rear ends and the bottom.

  The leak detection device A according to the present invention is inserted into the pipe B through which the liquid flows, and moves along the substantially center of the pipe B, while the sound transmitted through the liquid when the liquid flows. Is collected by a sound collecting member, the collected sound is recorded as sound data on a recording member, and can be detected by a position detecting member for detecting a moving position in the pipe B.

  In particular, the leak detection device A is provided with a reference clock, and a device including a recording member for recording sound data and a position detection member for detecting a moving position is controlled based on a clock signal generated from the reference clock. . That is, the recording member records sound data at the same timing, and the position detection member is configured to detect the moving position of the moving body.

  The sound collecting member collects the sound that is generated when the pressure fluid flows through the pipeline where leakage should be detected and is transmitted through the liquid, and is capable of exhibiting this function. Can be used. It is preferable to use a small microphone as such a sound collecting member. Whether the sound data of the sound collected and stored by the sound collecting member is analog information or digital information is not limited, and may be any information.

  The sound collected by the sound collecting member is recorded on the recording member as sound data. The recording member in the present invention may be any member as long as it has a function of recording the collected sound, and a recorder, a storage element, or the like can be selectively used according to the type of information.

  The position detection member is for detecting the position of the water leakage detection device in the pipeline where leakage should be detected. Any device capable of exhibiting such a function can be used. As this position detection member, a member configured by combining a gyro and an acceleration sensor can be used.

  When a gyroscope and an acceleration sensor are used as the position detection member, the moving position from the point in time when the moving body constituting the leak detection device is inserted into the pipe where the leak should be detected is calculated by integrating the gyroscope and the acceleration sensor. It is stored independently or in a storage means mounted on the moving body. In this way, communication with the outside is not required for the purpose of detecting the position of the moving body, and the extension distance of the pipe line to be detected for leakage is determined by the capacity of the power source accommodated in the moving body and the collected sound. The recording capacity of the recording member to be recorded is set according to the conditions such as.

  As described above, the signals generated from the gyroscope and the acceleration sensor are preferably stored in the storage means mounted on the moving body. However, the present invention is not limited to this configuration, and may be configured to be able to communicate with the outside wirelessly. good. In this case, a receiving device, a storage device, and an arithmetic device are installed on the ground, and the moving position of the moving body can be confirmed immediately. Furthermore, if the recording member is configured to be able to communicate with the outside, the moving position of the moving body and the sound data can be matched.

  In addition, a transmitting member that transmits a pulse signal corresponding to the reference clock is mounted on the moving body, and reception that receives a pulse signal transmitted from the transmitting member in synchronization with the reference clock of the transmitting member is provided outside the pipeline. It is also possible to configure the position detection member by arranging the members.

  With the position detection member configured as described above, it is possible to detect the position of the moving body in the pipeline by the time difference when the pulse signal transmitted from the transmission member is received by the reception member. In this case, the receiving member may be provided at one place or two places along the pipeline to be detected.

  Next, the configuration of the leak detection apparatus A according to the first embodiment will be described with reference to FIGS. In this embodiment and a second embodiment to be described later, the position detection member for detecting the moving position of the moving body in the pipeline is configured using a gyro and an acceleration sensor.

  The leak detection device A shown in the figure is configured for the purpose of detecting leaks in the water supply pipe B shown in FIG. 1, and when inserted into the pipe B to be detected, the pipe B It is configured to be able to move upon receiving the velocity energy of the circulating water.

  If the pipeline for which leakage is to be detected is water such as tap water, industrial water, and agricultural water, the sound propagation is affected by the water temperature. For this reason, it is preferable that the leak detection device is configured to be able to measure and record the water temperature in addition to recording sound and detecting position.

  The leak detection apparatus A according to the present embodiment includes a water temperature measuring member (not shown) configured to measure the water temperature and store the measured water temperature.

The leak detection device A is formed of a metal such as aluminum or plastic, and is a cylindrical main body 1a having a smooth outer peripheral surface and a cap 1 having a hemispherical smooth outer peripheral surface.
and a moving body 1 consisting of b. When the cap 1b is attached to the main body 1a via a packing (not shown), an accommodation space 1c for accommodating equipment necessary for detecting leakage of the pipeline is formed.

  In the accommodation space 1 c formed in the moving body 1, a sound collecting microphone 10 serving as a sound collecting member constituting the leakage detection device A, a recorder 11 for recording the sound collected by the sound collecting microphone 10, and a position detecting member 12. Are provided with a gyro 12a and an acceleration sensor 12b, a control unit 13 having a clock function and controlling the operation of the sound collecting microphone 10, the recording device 11, the position detection member 12, and the like.

  The moving body 1 in which the sound collecting microphone 10, the recording device 11, the gyro 12 a, the acceleration sensor 12 b, the control unit 13, the power supply 14, and the water temperature measuring member are housed in the housing space 1 c has a specific gravity of liquid. It is comprised substantially the same. For this reason, by inserting the moving body 1 into the pipeline B, it is possible to move downstream together with the liquid flowing through the pipeline B.

  In the present embodiment, the liquid flowing through the pipeline B maintains a laminar flow state.

  When the moving body 1 is inserted into the pipe B where the liquid flows in the laminar flow state, the moving body 1 moves along the approximate center (Ba) of the pipe B with the liquid flowing while maintaining the laminar flow state. To do. Then, in the process in which the moving body 1 moves along the approximate center of the pipe B, the sound generated from the liquid is recorded and the moving position in the pipe B is detected, so that there is no leakage and the leakage position. Can be detected.

  For example, as shown in FIG. 3, when the moving body 1 is in an eccentric position from the center Ba of the pipe B, the center Ba side of the outer peripheral surface of the moving body 1 has a large flow velocity V on the center side of the laminar flow. The flowing liquid contacts, and the liquid flowing at a small flow velocity v contacts the tube wall side. For this reason, a force in the direction of the liquid flowing at a large flow velocity V acts on the moving body 1 due to the difference in flow velocity (Vv) in contact with the moving body 1. Displaces to the center and stabilizes.

  The moving body 1 configured as described above is inserted into the pipe B from the valve plug C installed on the upstream side according to the above-described leakage detection method, and is moved along with the flowing liquid. In this movement process, sound collection is started with the elapsed time as a reference, sound recording is started, and detection of the movement position is started. When the moving body 1 reaches the valve plug portion C on the downstream side, the moving body 1 is collected by the collecting member 22 and separated from the pipe line B.

  Thereafter, by comparing the sound recorded by the moving body 1 and the moving position, the sound level line 30 with respect to the extending direction of the pipe B is made to correspond to the presence of the leaking portion 25 in the pipe B, the leak It is possible to estimate the amount of leakage at the section 25.

  For example, when the flow velocity of the liquid in the pipe B is lowered, there is a possibility that the moving body 1 may come close to and contact the wall surface of the pipe B. In order to avoid such contact, a plurality of contact members made of a linear or plate-like spring material formed in a gently curved shape may be disposed on the outer peripheral surface of the moving body 1 along the longitudinal direction. preferable. By comprising in this way, the mobile body 1 does not contact the wall surface of the pipe line B. Even if the contact member comes into contact with the wall surface and generates sound, it is constituted by a spring material formed in a curved shape, so that a large impact sound is generated or the moving body 1 is repelled by a reaction force. Nor.

  Next, the configuration of the moving body 2 constituting the leak detection apparatus A according to the second embodiment will be described with reference to FIG. In the figure, the two-dot chain line portion assumes a state in which the moving body 2 is inserted into the pipeline B. In the present embodiment, the same reference numerals are given to the same portions and portions having the same functions as those of the above-described embodiments, and the description thereof is omitted.

  The leak detection apparatus A according to the present embodiment includes a moving body 2 including a cylindrical main body 2a and a hemispherical cap 2b. A housing space 2c is formed inside the mobile body 2, and a gyro 12a, an acceleration sensor 12b, a control unit 13, a power source constituting a sound collecting microphone 10, a recording device 11, and a position detecting member 12 are formed in the housing space 2c. 14, a water temperature measuring member and the like are provided.

  The moving body 2 constituting the leakage detection device A configured as described above has a specific gravity set slightly smaller than the specific gravity of the liquid flowing through the pipe B. Therefore, when the moving body 2 is inserted into the pipeline B, the moving body 2 is levitated. For this reason, the specific gravity adjusting member 3 for preventing the floating of the moving body 2 and positioning it at the approximate center of the pipe B is provided.

  That is, a mounting portion 2d is formed on the outer peripheral surface of the main body 2a of the moving body 2, and the specific gravity adjusting member 3 is mounted on the mounting portion 2d. The specific gravity adjusting member 3 is formed of a string-like member or a flexible member such as a chain, and one end portion 3a is attached to the attachment portion 2d, and the other end portion 3b is the bottom surface of the target pipeline B. It is configured to be dragged by. Accordingly, the length of the specific gravity adjusting member 3 is set to be approximately equal to or longer than the radius of the target pipe B.

  Further, a flange 2e for receiving the energy of the flowing liquid is formed on the outer peripheral surface of the main body 2a of the moving body 2. Although the number of the flanges 2e is not limited, four flanges 2e are formed in this embodiment.

  When the moving body 2 constituting the leak detection apparatus A configured as described above is inserted into the pipe B, the moving body 2 maintains a posture in which the specific gravity adjusting member 3 is on the lower side. Further, the end 3 b side of the specific gravity adjusting member 3 is brought into contact with the bottom surface of the pipe B and dragged.

  In this embodiment, the specific gravity of the moving body 2 constituting the leak detection device A is set to 0.8 to 0.9 times the specific gravity of the liquid. When the moving body 2 is inserted into the pipe B, buoyancy according to the unit volume weight density of the liquid and the volume of the moving body 2 acts on the moving body 2. For this reason, assuming the moving speed of the liquid flowing in advance, when the moving body 2 moves along with the liquid along the approximate center of the pipe B, the end 3b of the specific gravity adjusting member 3 is in contact with the bottom surface. Assuming an angle (about 45 degrees) of the specific gravity adjusting member 3, the material is set so that the underwater weight of the specific gravity adjusting member 3 corresponding to the length of 45 degrees is equal to the buoyancy acting on the moving body 2. . The length of the end portion 3b of the specific gravity adjusting member 3 that is in contact with the bottom surface of the pipe B is about 1/4 to 1/3 of the 45 degree length of the specific gravity adjusting member 3. Is preferred.

  By setting the specific gravity adjusting member 3 as described above, when the moving body 2 is inserted into the pipe B, the moving body 2 moves along the approximate center of the pipe B, and the specific gravity adjusting member provided on the lower side. 3 is dragged by bringing the end 3b side into contact with the bottom surface, and the portion in the liquid is inclined at about 45 degrees.

  The specific gravity of the mobile body 2 constituting the leakage detection device A configured as described above is adjusted by the specific gravity adjusting member 3, and the end 3 b of the specific gravity adjusting member 3 is in contact with the bottom surface of the pipe B. For this reason, even if the liquid which distribute | circulates the pipe line B is a laminar flow state or a turbulent flow state, it is possible to move along the approximate center of the pipe line B.

  As in the first embodiment, the presence of the leakage portion 25 in the pipeline B and the amount of leakage in the leakage portion 25 are estimated in the process of moving along the approximate center of the pipeline B. Is possible.

  Next, another example of detecting the movement position of the mobile body 1 constituting the leak detection apparatus A in the pipeline B will be described with reference to FIG.

  In this example, a pulse signal is transmitted from the moving body 1 or 2 (hereinafter referred to as “moving body 1”) that moves in the pipe B, and this pulse signal is received outside the pipe B. The amount of movement is measured by detecting the time difference between the pulse signals transmitted in the process of moving in the road. For this reason, the moving body 1 is equipped with a transmitting member (not shown) for transmitting a pulse signal, and a receiving member for receiving the pulse signal constituting the position detecting member outside the pipe B. A receiving device 19 having the above is arranged.

  That is, a control unit (13) having a clock function is mounted on the moving body 1, and a sound wave, an ultrasonic wave, a radio wave, or the like is transmitted with a certain time interval corresponding to the reference clock of the control unit. A transmission member is mounted. The receiving device 19 includes a receiving member that receives a pulse signal transmitted from the moving body 1, a clock function that is synchronized with a control unit mounted on the moving body 1, and a recording function that records the pulse signal received by the receiving member. The control unit is arranged. And the position detection member (12) has these transmission members and reception members, and is comprised.

  The transmitting member and the receiving member described above are driven synchronously (corresponding to a reference clock), the pulse signal transmitted from the transmitting member is received by the receiving member, the time difference between the received pulse signals is measured, and the water temperature is simultaneously measured. Measure. It is possible to measure the moving amount of the moving body 1 by correcting the measured time difference data with the propagation velocity corresponding to the liquid water temperature. Then, by integrating the measured movement amount, it is possible to detect the movement position of the moving body 1 in the pipeline B.

  The receiving device 19 is disposed in a valve plug portion C disposed in the pipe B that is outside the pipe B. The number of the receivers 19 arranged in the pipe B is not particularly limited, but it is preferably installed at both ends of the pipe B where leakage should be detected, and the length of the pipe B to be detected It is preferable to set the number of arrangements accordingly.

  Each valve plug C is provided with a valve 18 having a function of extracting air mixed into the pipe B and a function of preventing liquid leakage. The valve 18 is caught inside the pipe B and collected at the top of the valve plug C. It is configured to be able to release fresh air. A small microphone 19a is provided inside the lid of the valve 18 of the selected valve plug C, and the small microphone 19a and the receiving device 19 are connected by a communication line 19b.

  For this reason, the pulse transmitted from the transmitting member mounted on the movable body 1 is released by opening the valve 18 of the valve plug C where the receiving device 19 is disposed and releasing the accumulated air and filling it with a liquid having pressure. The signal can be collected by the small microphone 19a. In addition, the collected sound can be recorded in the control unit by transmitting it to the receiving device 19 via the communication line 19b.

  Therefore, a pulse signal is transmitted from the moving body 1 moving in the pipe B, the pulse signal is received by the receiving device 19, and a time difference between the pulse signals transmitted in the process of moving in the pipe of the moving body 1 is detected. By doing so, it is possible to detect the movement position.

  The leak detection device and the leak detection method of the present invention can be used for a water pipeline and an oil pipeline as long as a liquid having a pressure flows therethrough.

A Leakage detection device B Pipe line C Valve plug portion 1, 2 Moving body 1a, 2a Body 1b, 2b Cap 1c, 2c Housing space 2d Mounting portion 2e Flange 3 Specific gravity adjusting member 3a, 3b End portion 10 Sound collecting microphone 11 Recording machine DESCRIPTION OF SYMBOLS 12 Position detection member 12a Gyro 12b Acceleration sensor 13 Control part 14 Power supply 18 Valve 19 Receiver 19a Small microphone 19b Communication line 20 Cast iron pipe 21 Insertion member 22 Collection member 25 Leakage part 30 Sound level line 31-33 part

Claims (10)

A leak detection method for detecting a leak in a pipeline through which a liquid with pressure flows.
A moving body configured to collect and record the sound transmitted through the liquid when the liquid with pressure flows and detect the moving position in the pipe is provided in the pipe. The sound data of the sound transmitted through the liquid recorded in the moving process of the moving body and the movement of the detected moving body in the pipe along with the flowing liquid along the center of the pipe. A leak detection method characterized by detecting a leak position in a pipe line according to a position. A leak detection device for detecting a leak in a pipeline through which a liquid with pressure flows.
A sound collecting member that collects sound transmitted through the liquid when the outer diameter is smaller than the inner diameter of the pipe and the liquid flows inside the pipe, and the sound collecting member collects the sound. A recording member for recording the generated sound and a position detection member for detecting a moving position in the pipe, and a moving body that moves with the liquid in the pipe,
The leak detection apparatus according to claim 1, wherein the specific gravity of the moving body is substantially the same as the specific gravity of the flowing liquid.   The leakage detection device according to claim 2, wherein the liquid having the pressure flows through the pipe while maintaining a laminar flow state.   4. The leak detection device according to claim 2, wherein the moving body is formed as a cylindrical body.   5. The member for detecting a moving position of the moving body in a pipeline has a gyro and an acceleration sensor mounted on the moving body. The leak detection device described in the above.   The member for detecting the moving position in the pipe of the moving body is a transmitting member that is mounted on the moving body and transmits a pulse signal corresponding to a reference clock, and a pipe for detecting leakage And a receiving member that receives a pulse signal transmitted from the transmitting member in synchronization with the clock of the transmitting member, and a pulse signal transmitted from the transmitting member that moves inside the pipe to be detected Is received by the receiving member, and the moving position in the pipeline of the moving body can be detected by the time difference when the pulse signal transmitted from the transmitting member is received by the receiving member. The leak detection device according to any one of claims 2 to 4. A leak detection device for detecting a leak in a pipeline through which a liquid with pressure flows.
A sound collecting member that collects sound transmitted through the liquid when the outer diameter is smaller than the inner diameter of the pipe and the liquid flows inside the pipe, and the sound collecting member collects the sound. A recording member for recording the generated sound and a position detection member for detecting a moving position in the pipe, and a moving body that moves with the liquid in the pipe,
A specific gravity adjusting member having a specific gravity slightly smaller than the specific gravity of the liquid, having flexibility on an outer peripheral surface of the movable body, and having a length at which an end portion contacts the bottom of the pipe A leak detection device characterized in that is provided.   The leakage detection device according to claim 7, wherein the moving body is formed as a cylindrical body.   The member for detecting the movement position in the pipe line of the said mobile body is comprised including the gyroscope and acceleration sensor mounted in this mobile body, The structure of Claim 7 or 8 characterized by the above-mentioned. Leak detection device.   The member for detecting the moving position in the pipe of the moving body is a transmitting member that is mounted on the moving body and transmits a pulse signal corresponding to a reference clock, and a pipe for detecting leakage And a receiving member that receives a pulse signal transmitted from the transmitting member in synchronization with the clock of the transmitting member, and a pulse signal transmitted from the transmitting member that moves inside the pipe to be detected Is received by the receiving member, and the moving position in the pipeline of the moving body can be detected by the time difference until the pulse signal transmitted from the transmitting member is received by the receiving member. The leak detection device according to claim 7 or 8.

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