JPH11271169A - Pipe-inspecting device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve propagation conditions in a pipe of an inspection sound that matches each inspection item and to obtain pipe inspection information according to each inspection item by setting the transmission direction of the inspection sound to be set into a pipe to be inspected so that an inclination angle can be changed for a pipe axis. SOLUTION: First, a speaker 9 is maintained in a first posture for orthogonally crosses the direction of a pipe diameter, a first inspection sound is transmitted in the direction of a second pipe, and a reflection sound between walls in the pipe is propagated in the direction of the pipe axis. A worker on the ground carries a sound-collecting tool 5 and moves in the burial direction of a pipe 2, and at the same time detects a reception sound and stores it in a storage device 8. Then, the speaker 9 is maintained in a second posture where an inspection sound transmission direction A is along the direction of a pipe axis Z, a second inspection sound is transmitted in the direction of the pipe axis, and the inspection sound is propagated in the direction of the pipe axis. A plurality of workers on the ground carry the sound-collecting tool 5, detect the direct wave of the reception sound at a position that differs from the burial direction of the pipe 2, and stores it in the storage device 8, thus obtaining the judgment data of the conditions (a burial position, a water supply position, an opening fracture part, and the like) of the pipe according to first and second sound pressure space distribution conditions of the obtained reception sound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for transmitting a test sound into a pipe to search and identify a position of the pipe concealed on a floor or a wall or a position of a cutting water generated in the pipe, or to generate a sound in the pipe. The present invention relates to a non-destructive inspection technique for a pipe using sound waves, for example, for specifying a position of an opening leaking part which is a damaged part.

[0002]

2. Description of the Related Art Various pipe inspection techniques have been proposed for the purpose of pipe inspection as described above. In such a method, as an example, the inspection sound is propagated into the pipe to be inspected, and the inspection sound is detected and detected outside the pipe, and the state of the reception sound (for example, the sound of the reception sound along the pipe axis) is detected. A method of examining the condition of a pipe from the pressure distribution) has been proposed. In the case of detecting the position of a buried pipe buried underground, the inspection sound is propagated in the pipe, and this propagated sound is moved on the ground surface in a direction perpendicular to the buried direction of the buried pipe. Receive and capture the spatial distribution of the received sound. In this case, the position where the received sound pressure is the highest can be estimated as the position of the buried pipe. Furthermore, when so-called cutting water (intruding water) is present in the buried pipe, the sound pressure distribution of the received sound is detected along the burying direction of the pipe. Therefore, the site where this significant decrease occurs,
It can be determined that it is a boundary portion between a portion where there is no water in the pipe and a portion where there is water. These inspection items are referred to as first inspection items in the present application. In such an inspection, conventionally, a so-called vertical pipe connected to a buried pipe (for a pipe buried horizontally in the ground, branches off from this pipe and is led out into the ground) In general, a speaker or the like is connected to the end of the ground side of a buried pipe in order to introduce sound waves into the buried pipe.

When there is a leak in a buried pipe buried in the ground, a so-called impulse sound is propagated in the pipe, and a direct wave of this pulse sound (first detected at a receiving position). The spatial distribution of the sound pressure (acoustic wave generated) is detected at a site on the ground side along the buried pipe. Even in this case, the position where the received sound pressure is highest can be estimated as the position where the buried pipe has a leak. Here, the reason for detecting the sound pressure of the direct wave and using it for the inspection is that the detected sound is propagated in the pipe, and, for example, when it is intended to estimate the highest part of the sound pressure as the leakage position, This is because when resonance occurs, the resonance part is easily mistaken for a leakage part. This inspection item is referred to as a second inspection item in the present application. Even when the pulse sound is propagated in the pipe as described above, conventionally, a speaker or the like is connected to the ground side end of the so-called vertical pipe connected to the buried pipe, and the We are trying to introduce sound waves. That is, conventionally, the method of inserting the test sound into the tube is substantially the same in the first test item and the second test item.

[0004]

However, when the first test item and the second test item are compared and examined, the state of propagation of the test sound (particularly, the state of occurrence of resonance) between the two items is as follows.
The inventors have found that different is preferred. That is, with respect to the first inspection item, it is preferable that strong resonance occurs in all portions of the tube, whereas with respect to the second inspection item, resonance in the radial direction of the tube does not occur. Is preferred. Considering such a situation, there is room for improvement in the conventional technology, and a tube inspection device using sound waves, particularly a mechanism mainly including a speaker that sends (inserts) sound waves into a tube. There was room for improvement in the structure. However, there is no idea to differentiate the speaker system from this point of view, as in the prior art.

Accordingly, an object of the present invention is to provide a pipe inspection apparatus which can realize a state of propagation of an inspection sound in a pipe, which is adapted to each of the above-mentioned inspection items, and which obtains pipe inspection information according to each inspection item. An object of the present invention is to provide a tube inspection method that can be obtained.

[0006]

To achieve the above object, a tube inspection apparatus according to the present invention is characterized by an inspection sound generating mechanism for generating an inspection sound, and an inspection sound generation mechanism for generating the inspection sound. , An inspection sound transmission direction setting mechanism for setting the transmission direction into the pipe to be inspected, the inclination direction of the inspection sound transmission direction set by the inspection sound transmission direction setting mechanism can be changed with respect to the pipe axis of the pipe. It is to be configured in. An inspection sound is generated by an inspection sound generation mechanism. Here, the generated inspection sound is transmitted into the pipe in the inspection sound transmission direction set by the inspection sound transmission direction setting mechanism. This sending direction is configured to be capable of changing the inclination angle with respect to the tube axis direction.
When inspecting an inspection item, an inspection sound is transmitted in a direction (tube diameter direction) orthogonal to the tube axis, and when inspecting the second inspection item, the inspection sound is transmitted along the tube axis (parallel). To)
An inspection sound is transmitted in the direction, and an inspection matching each item can be performed. Furthermore, as described above, not only is the tube axis perfectly perpendicular or parallel to the direction in which the inspection sound is sent out, but even if it is desired to incline slightly, the adjustment is performed well and the predetermined An inspection of the item can be performed.

In such an apparatus, as described above,
When it is desired to perform the first inspection item or the second inspection item with a relatively easy configuration, it is preferable to configure the apparatus as follows. That is, an inspection sound transmission direction setting mechanism is provided between a first posture in which the inspection sound transmission direction is a direction orthogonal to the tube axis and a second posture in which the inspection sound transmission direction is along the tube axis. In this case, the direction in which the inspection sound is transmitted can be set. With this configuration, it is possible to obtain a tube inspection device that can respond to the inspection of various items described above with a simple device configuration.

The pipe inspection method of the present invention for the second inspection item or the like for achieving the above object is as follows. In other words, the inspection sound is propagated into the pipe to be inspected, the inspection sound is received and detected outside the pipe, and the pipe inspection method for inspecting the state of the pipe from the sound pressure spatial distribution state of the received sound is performed. , Through the following procedure. That is, a pulse sound including a plurality of frequency components as an inspection sound is transmitted from the inspection sound generation mechanism in the tube axis direction of the tube, and this pulse sound (for example, impulse sound) is propagated in the tube axis direction, and the pulse sound is generated. The sound pressure spatial distribution of the direct wave is detected, and the condition of the pipe is inspected from the detected sound pressure spatial distribution. The inspection item targeted by this method is illustratively the second inspection item described above. When performing this inspection, it is preferable that resonance of the inspection sound (resonance due to gas vibration in the tube radial direction) does not occur in the tube, and a so-called compression wave is generated while forming the compression portion in the tube axis direction. When propagating, no extra resonance occurs inside the tube. Therefore, it is possible to maximize the sound pressure of the direct wave, which is the leak sound from the broken portion of the opening of the pipe. result,
By employing this method, for example, a broken portion of the opening of the pipe can be detected more reliably.

As described above, there are cases where the first and second inspection items are desired to be sequentially performed on a predetermined pipe. In such a case, it is preferable to adopt the following method. That is, the following method is used to propagate the inspection sound into the pipe to be inspected, receive and detect the inspection sound outside the pipe, and execute the pipe inspection method of detecting the state of the pipe from the state of the received sound. Is taken. The first inspection sound is transmitted in the radial direction of the pipe, and the reflected sound is propagated in the pipe axis direction while being reflected between the inner walls of the pipe, and the sound pressure spatial distribution state of the received sound is detected. (1) a first inspection step of obtaining a sound pressure space distribution state, and a second inspection sound is transmitted in a pipe axis direction of the pipe,
A second inspection step of transmitting the second inspection sound in the tube axis direction, detecting a sound pressure spatial distribution state of a received sound of a direct wave of the second inspection sound, and obtaining a second sound pressure spatial distribution state of the received sound; To obtain both the first sound pressure space distribution state and the second sound pressure space distribution state, and determine the state of the pipe from both. In the case where this method is adopted, in the first inspection step, a first inspection sound is transmitted in the radial direction of the pipe, and this sound is reflected in the pipe axial direction in the pipe axial direction while being reflected between the pipe inner walls. Propagate. Therefore, in this case, it is easy to generate a resonance sound according to the pipe diameter. As a result, when the spatial sound pressure distribution state of the received sound is grasped according to this method, for example, the position search of the pipe,
It is possible to obtain the first sound pressure spatial distribution state which is mainly useful for exploring the position of the pipe head. Next, in the second inspection step, a second inspection sound is transmitted in the direction of the tube axis, and this sound propagates in the direction of the tube axis as a compression wave with a low degree of resonance. Therefore, in this case, for example, if the spatial sound pressure distribution state of the sound pressure of the direct wave is grasped, the second sound pressure spatial distribution state which is mainly useful for, for example, exploring the leak position of a pipe can be obtained. . As a result, it is possible to easily obtain sound pressure data for various inspection items, which can satisfactorily cope with these item inspections, and to appropriately grasp the condition of the pipe.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a pipe inspection apparatus 1 according to the present invention will be described below with reference to the drawings, and a case where the pipe inspection method according to the present invention is executed using the pipe inspection apparatus 1 will be described. I do. 1 and 2 show a state in which the pipe inspection device 1 of the present application is used on site. A buried pipe 2 to be inspected is buried almost horizontally in the ground at the site, and a vertical pipe 3 extends from the buried pipe 2 to the ground. By the way, in the inspection, the inspection worker 4
Carries out the inspection work by bringing the pipe inspection apparatus 1 of the present application and the headphones 6 provided with the sound collector 5 to the site. The sound collector 5 is provided with a microphone 7, and the worker 4 can listen to the sound received by the microphone 7 with the headphone 6. The received sound is recorded in the recording device 8. Pipe inspection device 1 of the present application
Is basically provided with a speaker 9 introduced into a tube, and a support mechanism 10 for supporting the speaker 9 and setting the posture of the speaker 9 in the tube. That is, the speaker 9 functions as a test sound generating mechanism for generating the test sound of the present application, and the support mechanism 10 transmits the test sound generated by the test sound generating mechanism into the pipe to be tested. It has a role as an inspection sound transmission direction setting mechanism for setting the transmission direction. At the distal end of the support mechanism 10, a posture setting mechanism 12 for setting the posture of the speaker 9 with respect to the base part 11 of the support mechanism (the inclination angle of the base part 11 can be freely adjusted up to 90 degrees).
It has. Therefore, as shown in FIGS. 1 and 2, the pipe inspection apparatus 1 of the present invention is mounted on the open end 3a of the vertical pipe 3 in a state where the explosion-proof state can be maintained, and the speaker 9 is introduced into the pipe. The direction is a first posture (posture shown in FIG. 1) perpendicular to the pipe axis Z of the buried pipe 2, and a second posture (posture along the pipe radial direction) along the pipe axis Z. Therefore, it is a preferable posture that the tube axis and the center of the speaker substantially coincide with each other). Further, the posture setting mechanism 12 allows the speaker 9 to take an intermediate position between the two positions. That is, by providing the inspection sound transmission direction setting mechanism, the transmission direction of the inspection sound can be changed in the inclination angle with respect to the pipe axis Z of the pipe.

The posture that the speaker 9 can adopt will be described.
Can be selectively set between a first posture in which the direction is orthogonal to the tube axis Z and a second posture in which the inspection sound sending direction A is along the tube axis Z. The speaker 9 is provided with a test sound generating mechanism main body 100 for driving, and a continuous sound, a rhythm sound having a constant rhythm, an impulse sound, and the like are output from the speaker 9 in accordance with an outgoing signal generated therefrom. It is configured to be able to occur as. The above is the basic configuration of the pipe inspection device 1 of the present application.

A pipe 2 will be described below using the pipe inspection apparatus 1 of the present application.
The case where the inspection is performed will be described for each of the inspection items described above. 1. In the case of inspecting the first inspection item In this case, as shown in FIG.
Is maintained in a first position orthogonal to the pipe diameter direction, and a first inspection sound is sent out in the pipe diameter direction of the pipe 2 so that the reflected sound generated while mainly reflecting between the pipe inner walls is reflected in the pipe axis direction. To be propagated. By doing so, within the pipe, the resonance sound propagates in the pipe. In this case, it is effective to use a continuous sound having a constant frequency. On the other hand, on the ground, worker 4
Carries the sound collector 5 and detects the received sound while moving in the direction in which the pipe 2 is buried. This result is stored in the recording device 8 and used for the later analysis. With this operation, the sound pressure spatial distribution state of the received sound can be detected, and the first sound pressure spatial distribution state of the received sound can be obtained. This detection result can be used for checking the buried position of the buried pipe 2 and for checking the presence or absence of a cutting water. Thus, the first inspection step is completed. 2. In the case of inspecting the second inspection item In this case, as shown in FIG.
Is maintained in the second posture in which the inspection sound transmission direction A is along the tube axis Z direction (in this case, the speaker 9 is in a posture that is bent with respect to the support mechanism base end portion 11).
The second inspection sound is transmitted in the tube axis direction, and the inspection sound is propagated in the tube axis direction. By doing so, in the tube, the generation of the resonance sound is suppressed, and the inspection sound propagates in the tube. More specifically, a pulse sound (for example, Qingdao pulse sound which is a kind of impulse sound) including a plurality of frequency components as an inspection sound is transmitted in the tube axis direction of the tube, and the pulse sound is propagated in the tube axis direction. Let it. On the other hand, on the ground, the plurality of workers 4 bring the sound collecting device 5 and detect the direct waves of the received sound at different positions in the burying direction of the pipe 2. This result is stored in the recording device 8 and used for the later analysis. Therefore, by this operation, the sound pressure spatial distribution state of the direct wave of the pulse sound can be detected, and the second sound pressure spatial distribution state of the received sound can be obtained from the detected sound pressure spatial distribution state. This detection result can be used for the detection of the broken portion 20 of the opening of the tube. Thus, the second inspection step ends.

As a result, both the first sound pressure space distribution state and the second sound pressure space distribution state are obtained, and from both of them, the judgment data such as the state of the pipe (burial position, pouring water position, position of the damaged portion of the opening) and the like. Can be obtained.

FIGS. 3 to 6 show differences in impulse responses when the test sound is inserted in different states when the above-described inspection method is performed. FIGS. 3 and 4 show 200A (200
5 and 6 show the impulse response (upper part) and the frequency characteristics (lower part) of the 50A (50φ) polyethylene pipe due to the difference in the sound insertion direction (sound transmission direction from the speaker side) with respect to the steel pipe of FIG. . 3 and 5 correspond to the case where the test sound is transmitted from the speaker in the tube axis direction, and FIGS. 4 and 6 correspond to the case where the test sound is transmitted from the speaker in the tube diameter direction. In any of the figures, in the comparison of the sound wave insertion direction (the sound transmission direction from the speaker side), it can be seen that the resonance has a larger resonance peak when the test sound transmission direction is in the tube diameter direction. . Therefore,
By appropriately adjusting the sending direction of the inspection sound with respect to the tube axis direction, an inspection result suitable for various purposes can be obtained.

[Another Embodiment] (A) In the above embodiment, the pipe inspection apparatus 1
Is shown with a support mechanism 10 for supporting the speaker 4, but the speaker itself is attached to the pipe end of the pipe to be inspected, and the attitude of the speaker with respect to the pipe axis or the like is changed, so that the speaker is transmitted into the pipe. It is also possible to change the sending direction of the inspection sound to be performed. FIG. 7 shows an example of this configuration. As shown in the drawing, the pipe inspection apparatus 1 is configured to be directly attachable to the end of the buried pipe 2 in an explosion-proof state, and includes an apparatus main body 14 having a space 13 for accommodating a speaker therein. Have been. Further, in this device main body 14, in a state where the buried pipe 2 is connected to the buried pipe connecting portion 15 of the device main body 14, the speaker 90 is connected to the device main body internal space 1.
3, the generated sound sending direction B may take an alternate manner between a posture (first posture) orthogonal to the tube axis Z and a posture (second posture) parallel to the tube axis Z. It is configured to be able to. In this example, the device main body 14 and a mechanism provided in the device main body 14 and capable of changing the position of the speaker (specifically, a mounting mechanism of the speaker 90 provided to face the buried pipe connection portion 15) The mounting mechanism for mounting the speaker 90 in a posture orthogonal to the pipe axis direction determined at the buried pipe connection part 15) constitutes the inspection sound transmission direction setting mechanism. Here, it is configured to function as a resonance box for the detected sound in the apparatus main body 14, and when the first posture is taken, the light is reflected in the vertical direction (vertical direction) of FIG. While repeating
An inspection sound is transmitted into the tube. On the other hand, in the second posture, the central axis of the speaker 90 is configured to coincide with the tube axis Z, and the sound wave generated from the speaker 90 is
As it is, it is transmitted within the pipe as a compression wave.

Therefore, even in the case of this device configuration,
By appropriately setting the direction B of the inspection sound and the direction of the tube axis Z, the first inspection step and the second inspection step referred to in the present application can be performed, and a good inspection of the tube can be performed. In this configuration, a pair of speakers taking the first and second postures may be provided in a fixed state in advance.

With respect to the case where the method of the present invention is adopted, the test sound includes a general continuous sound, a sound having a specific rhythm,
Sound of a specific frequency or the like can be used. Such a sound is particularly preferable when the speaker takes the first posture referred to in the present application. On the other hand, when taking the second posture described in the present application, it is preferable to use the sound pressure of a direct wave, so that it is preferable to use the pulse sound as the inspection sound, but sounds such as chirp waves and white noise can also be used. . Furthermore, on the sound reception detection side,
In addition to the above-described microphone, the detection may be performed by a piezoelectric vibration sensor, a stethoscope, or, in some cases, a human ear.
Furthermore, in the present application, it is preferable to use a speaker having high directivity as much as possible from the above-mentioned use situation,
It is better to use cones with high directivity

[Brief description of the drawings]

FIG. 1 is a diagram showing a use state (when resonance is used) of a tube inspection apparatus of the present application.

FIG. 2 is a diagram showing a use state of the tube inspection apparatus of the present application (when resonance is not desired).

FIG. 3 is a diagram showing the results of a verification test on a 200A steel pipe according to the present invention when an inspection sound is transmitted in the pipe axis direction.

FIG. 4 is a diagram showing the results of a verification test on a 200A steel pipe according to the present invention when an inspection sound is transmitted in the pipe diameter direction.

FIG. 5 is a diagram showing the results of a verification test on a 50A polyethylene pipe according to the present invention when an inspection sound is transmitted in the pipe axis direction.

FIG. 6 is a diagram showing the results of a demonstration experiment on a 50A polyethylene pipe according to the present invention when an inspection sound is transmitted in the pipe diameter direction.

FIG. 7 is a diagram showing another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipe inspection apparatus 2 Buried pipe (tube) 9 Speaker 12 Posture setting mechanism A Transmission direction of inspection sound B Transmission direction Z Pipe axis direction

Claims (4)

[Claims] An inspection sound generating mechanism for generating an inspection sound;
An inspection sound transmission direction setting mechanism for setting a direction of transmission of the inspection sound generated by the inspection sound generation mechanism into the pipe to be inspected, wherein the inspection sound is set by the inspection sound transmission direction setting mechanism. A pipe inspection device in which a sending direction is configured to be able to change an inclination angle with respect to a pipe axis of the pipe. 2. A method according to claim 1, wherein a direction in which the test sound is transmitted is a direction perpendicular to the tube axis, and a second position in which the test sound is transmitted along the tube axis. 2. The tube inspection apparatus according to claim 1, wherein the inspection sound sending direction in the inspection sound sending direction setting mechanism can be selectively set. 3. A pipe inspection method for transmitting an inspection sound into a pipe to be inspected, receiving and detecting the inspection sound outside the pipe, and inspecting the state of the pipe from a sound pressure spatial distribution state of the received sound. A pulse sound including a plurality of frequency components as the inspection sound is transmitted from the inspection sound generation mechanism in the tube axis direction of the tube, and the pulse sound is propagated in the tube axis direction. A pipe inspection method for detecting a sound pressure spatial distribution state of a wave and inspecting a state of the pipe from the detected sound pressure spatial distribution state. 4. A pipe inspection method for transmitting an inspection sound into a pipe to be inspected, receiving and detecting the inspection sound outside the pipe, and detecting a state of the pipe from a state of the received sound, wherein the method comprises: The first inspection sound is transmitted in the pipe radial direction, and the reflected sound is propagated in the pipe axis direction while being reflected between the pipe inner walls, and the sound pressure spatial distribution state of the received sound is detected. First
A first inspection step of obtaining a sound pressure spatial distribution state; a second inspection sound is transmitted in a tube axis direction of the tube, and the second inspection sound is propagated in a tube axis direction, and a direct wave of the second inspection sound is transmitted. Performing a second inspection step of detecting a sound pressure spatial distribution state of the received sound to obtain a second sound pressure spatial distribution state of the received sound. The first sound pressure spatial distribution state and the second A pipe inspection method for obtaining both of a sound pressure space distribution state and inspecting a pipe state from the both.