JP2000154888A - Probing method for piping structure and piping probing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for probing a structure of an embedded pipe independently of the other embedded object by adopting a comparatively simple method at site. SOLUTION: When a structure of an embedded pipe 1 is probed outside of soil in which it is arranged, sound wave is propagated in the embedded pipe, propagation sound propagated through soil layers from the embedded pipe 1 is detected on a surface of soil, and frequencies of the detected sound are analyzed to probe a structure of a pipe in a piping section corresponding to the detection position based on the obtained results of frequency analysis by utilizing resonance frequency of the sound propagated in the pipe.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, a pipe buried in the ground, the structure of a pipe comprising a plurality of pipe members (for example, a pipe having a plurality of diameters, a pipe joint, etc.). The present invention relates to an exploration method of a piping structure for performing structure identification such as a type of a piping member by specifying a diameter, and an exploration apparatus that can be used when such a method is performed.

[0002]

2. Description of the Related Art Conventionally, the following method has been adopted as a technique for estimating the structure of an underground pipe as a combination of a plurality of pipe members. Method 1 Estimate the piping structure based on the buried piping drawing created when burying the piping. Method 2 At the site, a radar probe or an ultrasonic probe with transmission and detection of a probe wave is arranged at multiple points in the search area, and the position of the pipe,
Identify the structure. Method 3 Actually perform the excavation work,
Exposing the piping and specifying the structure of the piping.

[0003]

As described above, each conventional technique has the following problems. When the method 1 is adopted, if the time since the burying work has elapsed, the piping drawing may be lost or the state of the improvement work may not be reflected. In addition, there is an error in the piping drawing or details of the piping (for example, the presence or absence of a joint)
Is omitted in some cases, which is not enough to grasp the exact situation. When the method 2 is employed, since the reflection of the exploration wave is used, even if there is another buried object in the ground, the exploration wave is reflected therefrom, so that it is not always possible to detect a pipe to be found. Furthermore, when a radar wave is used as the exploration wave, if a reinforcing bar is installed in the ground, the radar is reflected by the reinforcing bar and cannot detect a pipe buried deeper than the reinforcing bar. In the method 3, since the excavation work is actually required, the labor is excessive, and depending on the site, it may not be possible to easily perform the excavation work.

Accordingly, it is an object of the present invention to provide a method capable of exploring a structure such as a buried pipe independently of other buried objects while employing a relatively simple method on site. . In addition, today, an attempt has been made to run an in-pipe traveling vehicle in a pipe to inspect the pipe condition. However, in such an in-pipe traveling, the inside diameter of a pipe at a location where the traveling vehicle is currently traveling is being examined. But you may need to know to what extent. In such a case, it is preferable that the inner diameter of the pipe at the traveling position can be determined with a relatively simple structure, but it is an object of the present application to obtain such a technique.

According to the present invention, there is provided a method for exploring a piping structure for detecting a piping structure from outside a coating layer in which the piping is provided. As described in Item 1, while propagating a sound wave in the pipe, a propagation wave propagating from the pipe through the coating layer outside the coating layer (this wave is a sound wave. Or a vibration wave of the coating layer), perform a frequency analysis of the detected detection wave, and, based on a frequency analysis result obtained, determine a pipe position at the pipe portion corresponding to the detection position. To explore the structure. In this method, sound for exploration is inserted into the pipe (the space formed in the pipe, not in the pipe material, and filled with the fluid that is the sound propagation medium) and propagated. Can be The inserted sound propagates through the pipe. When the pipe is covered with a covering layer such as soil, the sound is transmitted from the pipe to the covering layer, and the sound is transmitted to a vibration signal ( (Detected wave). Then, in the present application, the frequency analysis of the detected wave is performed. As a result, a spectrum of the detected wave can be obtained. This spectrum includes information related to the structure of the pipe at the pipe portion corresponding to the detection position. Here, "corresponding" means, for example, in the case of a buried pipe buried horizontally in soil as shown in FIG. 1, it means a pipe portion buried almost vertically below the detection position. This correspondence depends on the acoustic environment of the target, but if the general state of the target is known,
A certain degree of correspondence can be specified, and is sufficiently practical. By the way, for example, when a pipe is formed by a combination of a normal pipe and a sleeve having different inner diameters, the sound velocity of the medium in the pipe can be considered to be constant, so that the sound propagates from a pipe portion formed of these pipe members. The spectrum of the incoming sound will have peaks at different frequencies according to its inner diameter. As a result, information on the structure of the pipe, such as the diameter of the pipe and the presence of a discontinuous portion, can be obtained due to the difference in the peak positions.

[0005] In the above method, when the pipe comprises a plurality of pipe members having different inner diameters, the inner diameter of the plurality of pipe members and the sonic velocity of a medium existing in the pipe may be increased. Therefore, it is preferable to specify the piping member at the piping portion corresponding to the detection position in the correspondence between the resonance frequency of the medium in the piping member and the peak position or the detection level in the obtained frequency analysis result. That is, the piping member constituting the piping is usually
Since the types are limited according to the purpose of use and the like, the inner diameter and the like of each of the limited types of piping members can be determined, and as a result, the gas type of the gas in these piping members can be determined. When the state (pressure / temperature) is specified, the resonance frequency of the medium in the tube (for example,
The resonance frequency at which resonance occurs in the tube cross-sectional direction is specified.
Therefore, the resonance frequency of the medium in the pipe member and the peak position in the obtained frequency analysis result are compared and compared, and if they match, a specific pipe position is determined based on the matching state. It can be determined that there is a high possibility that the located piping member is made of a piping member whose agreement is recognized. In this case, even when the peak cannot be recognized, a similar determination can be made by increasing the detection level (spectral intensity) near the resonance frequency.

In the above-mentioned method, the method in the case where the vehicle is covered with the coating layer has been described. It can be usefully used even when the user wants to travel. That is, in the method for searching a pipe structure for searching a structure of a pipe, as described in claim 3, while transmitting a sound wave in the pipe, a search position in the pipe different from a sound source of the sound wave. Then, it is preferable to detect a propagating sound to be propagated, perform a frequency analysis of the detected sound, and search a pipe structure at the search position from the obtained frequency analysis result. In this case, too, the sound that propagates in the pipe uses a spectrum that depends on the structure of the pipe portion corresponding to the propagation position. Also in this example, the search sound is propagated in the pipe, and the propagated sound is detected in the pipe. Since such a detection sound depends on the pipe structure at the detection position, it is possible to specify the detection position, for example, the inner diameter of the pipe, from the frequency analysis result in accordance with the above-described method. Such inner diameter data is useful in controlling the attitude and traveling of the in-pipe traveling vehicle.

The above is the method proposed by the present application, but it is preferable to adopt the following structure as a search device using such a method. That is, as described in claim 4, while including a sound transmitting device and a vibration wave detecting device, the diameter-related information on a plurality of pipe members constituting a pipe to be searched, and in the pipe A resonance frequency deriving unit for obtaining a resonance frequency of the medium in each of the pipe members based on sound velocity information of the existing medium, and performing a frequency analysis of a detection wave detected by the detection device. Means for outputting a frequency analysis result obtained by the frequency analysis means and each resonance frequency obtained for each pipe member by the resonance frequency derivation means. The transmitting device performs the insertion and transmission of the exploration sound into the pipe, and detects the sound propagating in the pipe from the outside of the coating layer in the case of claim 1 and the transmitting apparatus in the case of claim 3. Detect at different pipe locations. The detected wave thus detected is subjected to frequency analysis by frequency analysis means. Separately, the present apparatus is provided with a resonance frequency deriving unit, which includes diameter-related information on a plurality of pipe members constituting a pipe to be searched and sound velocity information on a medium present in the pipe. Is used to determine the resonance frequency of the medium in each of the pipe members. For example, the resonance frequency in the direction of the tube cross section is determined.
Then, when the frequency analysis result obtained in this way and the resonance frequency according to the structure of the pipe are output in association with each other by the output unit, the operator specifies the piping member at the exploration site based on the correspondence result. be able to.

It is also preferable to employ the following structure as the exploration device. That is, as described in claim 5, a sound transmission device and a vibration wave detection device, and the diameter-related information about a plurality of pipe members constituting a pipe to be searched, and in the pipe A resonance frequency deriving unit for obtaining a resonance frequency of the medium in each of the pipe members based on sound velocity information of the existing medium, and performing a frequency analysis of a detection wave detected by the detection device. Means, the peak position in the frequency analysis result obtained by the frequency analysis means,
When the resonance frequency deriving means is any one of the resonance frequencies obtained for each pipe member, the pipe part corresponding to the detection position for detecting the detection wave may be a pipe member corresponding to the resonance frequency. It is provided with a judging means for judging that the degree is high. Also in the case of this configuration, the transmitting device inserts and transmits the exploration sound into the pipe, and the sound propagating in the pipe is detected by the detecting device from the outside of the coating layer in the case corresponding to claim 1, and the case corresponding to claim 3. Is detected at a position in the pipe different from that of the transmitting device. The propagation sound thus detected is subjected to frequency analysis by frequency analysis means. Separately, the present apparatus is provided with a resonance frequency deriving unit, which includes diameter-related information on a plurality of pipe members constituting a pipe to be searched and sound velocity information on a medium present in the pipe. Is used to determine the resonance frequency of the medium in each of the pipe members.
For example, the resonance frequency in the direction of the tube cross section is determined. In the apparatus according to the fifth aspect, the judging means may determine whether a peak position in a frequency analysis result obtained by the frequency analyzing means is one of resonance frequencies obtained for each pipe member by the resonance frequency deriving means. In such a case, the configuration is such that it is determined that there is a high possibility that the pipe portion corresponding to the detection position for detecting the detection wave is a pipe member corresponding to the resonance frequency. Therefore, the correspondence between the spectrum and the resonance frequency is automatically determined, and the determination result that the candidate of the piping member is estimated can be obtained.
Also in this case, the structure of the piping can be estimated using the resonance frequency.

In the exploration described so far,
The sound wave is actively propagated in the pipe, and the sound wave is used to detect the sound of the pipe at the search position (detected wave including the detected sound) based on the frequency analysis result. Although the diameter, pipe type, and the like are determined, for example, in a relatively high-pressure gas pipe, the gas to be supplied is always flowing, and as a result, a sound generated by such a gas flow is generated. , Exists in the tube. Such a sound naturally contains a resonance component that depends on the piping structure (for example, the piping diameter) at the site. Therefore, it is also possible to use the sound existing in the exploration unit for the purpose of the exploration of the present application based on different factors from such exploration. In this case, as described in claim 6, corresponding to the description of claim 3 described above, when exploring the structure of the pipe, the propagation sound propagating in the pipe is detected at the search position. , The frequency of the detected sound is analyzed, and the structure of the pipe at the search position can be searched from the obtained frequency analysis result. In this case, without propagating sound waves in the tube,
Detects noise, etc. existing in the pipe, and based on this sound,
The structure of the piping can be explored in the same manner as described above.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a state in which the structure of a gas pipe 1 buried underground is being searched by applying the method for searching for a pipe structure of the present application. In this method, sound waves propagating in the pipe 1 are used for exploration.

In the exploration of the piping of the present application, an exploration apparatus 2 having a configuration unique to the present application is used. First, an outline of the search device 2 will be described. The search device 2 includes a search device main body 3, a speaker 4, and a vibration pickup (a type of vibration wave detection device) 5 as main components. Here, the speaker 4 is an explosion-proof type, and is configured to be attachable to the tube end 6 exposed on the ground. The speaker 4 is configured to be driven to generate a predetermined sound wave in response to a sound generation command from the search device main body, and to send a pulse sound including at least a plurality of frequency components into a tube to be searched. . Next, the vibration pickup 5 will be described. A plurality of vibration pickups 5 are provided, and a ground vibration pickup 5a is disposed on the ground surface side and picks up vibration sound transmitted from underground. In the example shown in FIG.
The sound receiving information picked up by these vibration pickups is sent to the search device main body 3 side for use later.

Next, the configuration of the search apparatus main body 3 will be described. The exploration apparatus body 3 includes Qingdao pulse generating means 31 storing predetermined information for generating Qingdao pulse sounds from the speaker 4, and frequency analyzing means 32 for performing frequency analysis of the sound detected by each vibration pickup 5. I have. Further, the exploration apparatus main body 3 is provided with a resonance frequency deriving means 33, and according to the inner diameter information of each of a plurality of pipe members constituting a separately input pipe and the sound velocity related information of the fluid in the pipe, the resonance frequency derivation means 33 is provided. It is configured so that the resonance frequency in the tube cross section direction can be obtained. Each vibration pickup 5 output from the frequency analysis means 32
Display means 34 for displaying both the frequency analysis result of the detection wave (vibration sound) detected by the above and the resonance frequency related to each pipe member 1a which is the output from the resonance frequency derivation means 33. Therefore, for example, as shown in FIG. 3, both the frequency analysis result of the detection wave detected by each vibration pickup 5 and the mark (arrow) indicating a specific frequency corresponding to the resonance frequency separately obtained,
It is displayed on the display means 34. In addition, the exploration apparatus main body 3 includes a frequency analysis result of a detection wave detected by each vibration pickup 5 output from the frequency analysis means 32 and a pipe member 1 a output from the resonance frequency derivation means 33. When the peak position P in the frequency analysis result obtained by the frequency analysis means 32 is any one of the resonance frequencies obtained for each pipe member 1a by the resonance frequency derivation means 33 based on the related resonance frequency. Further, there is provided a judging means 35 for judging that there is a high possibility that the pipe portion corresponding to the detection position for detecting the detection wave is a pipe member corresponding to the resonance frequency.
Therefore, based on the estimation result by the judging means 35, it is possible to estimate what kind of pipe member the pipe portion from which the detection wave detected by the vibration pickup 5 is emitted.

The structure of the resonance frequency deriving means 33 will be further described.
This will be described in detail below. Tube cross section in this means 33
The resonance frequency f in the direction (cross section in the direction traversing the tube) is
Is determined by f = C × U_mn/ (2πa) where C is the speed of sound in the pipe (m / s), and the gas content in the pipe
And the temperature and pressure in the pipe are determined according to a known formula.
You. A is a pipe radius (m). And U _mnIs a table
The value depends on the resonance mode as shown in FIG.
Exists. The information of gas type, gas pressure and temperature is calculated by
This is reference information when deriving.

[0014]

[Table 1]

Each resonance mode corresponds to the vibration pattern shown in FIG. A specific numerical example is as follows.
For methane at ° C., the speed of sound is 434.1 (m / s); for air, the speed of sound is 334.5 (m / s).
At this time, the resonance frequency in the tube having a tube radius of 0.1 (m) is from 1337, 2187, 2732, 2
999, ... Hz. In addition, the air is 10
30, 1685, 2105, 2310,... Hz. Table 2 shows an example of calculation derivation in the case of air under the above conditions. The resonance frequency is calculated on the assumption that the temperature is 20 ° C.

[0016]

[Table 2]

Therefore, the resonance frequency that causes resonance in the direction of the cross section in the so-called pipe corresponds to an infinite number of modes,
An infinite number exists discretely. Then, the resonance frequency deriving means 33 can derive the resonance frequency of each of these resonance frequencies individually in accordance with the on-site conditions corresponding to the inner diameter of the pipe member.

The above is the basic configuration of the exploration apparatus 2 of the present invention. The exploration method to be used is directed to the gas pipe 1 (an example of an embedded pipe) buried in the front road of each home 7. The case will be described. FIG. 1 shows a city gas piping system B that supplies city gas to each household 7.
That is, each household 7 is provided with a low-pressure gas pipe 9 buried in a front road 8 thereof.
From (an example of the pipe 1), the pipe drawn into the premises of each home 7 via the pull-in pipe 10 is first sent out to the above-ground portion as a standing pipe 11, and then the gas supply position ( (Not shown). A so-called gas meter (not shown) is provided at a predetermined position of the standing pipe 11. In the exploration work, a gas meter (not shown) is removed from the upright 11 to use the upright 11 described above.
The speaker 4 is attached to one tube end 6. The speaker 4 receives the information from the Qingdao pulse generation means 31 described above and receives a control command, and sends a Qingdao pulse, which is a pulse sound containing a plurality of frequency components, into the tube. Here, the Qingdao pulse is a pulse sound including a plurality of frequency components, and is a sound that can be transmitted to an acoustic system to obtain an impulse response of the acoustic system.
Measurement technology vol. 12-4 pp. 35-43 (198
This is described in detail in 4). Further, as will be understood from the description, this Qingdao pulse is an optimized Qingdao pulse or TPS (Time-Stretched P).
ulse), which is a signal obtained by extending a time signal having a flat power spectrum in a predetermined frequency range on the time axis. Morphologically, it is close to an impulse sound, and its frequency range generally ranges from 0 to 10 kHz.

On the other hand, a plurality of ground-side vibration pickups a are arranged on the ground along the buried positions of the gas pipes 1 prepared in advance. Therefore, the vibration pickups 5a can pick up vibration sounds (detection waves) leaking into the ground from the pipe portions corresponding to the respective detection areas. Information from the front-side vibration pickup 5a in each place is collected in the exploration device main body 3, and is analyzed in the frequency domain by the frequency analysis means 32, and a frequency analysis result (spectrum) of a detected wave corresponding to each position is obtained. . On the other hand, the information of the piping member 1a constituting the piping and the information on the internal medium are separately input to the exploration apparatus main body 3 by the input means. Here, the so-called inner diameter of the pipe member 1a is one important input condition. Further, information relating to the gas existing in the pipe is input. That is, at least the gas type, gas pressure, and temperature of the gas in the pipe are input. In accordance with such input information, the resonance frequency deriving means 33 calculates a resonance frequency corresponding to each pipe member. As described above, in the display means, the spectrum of the detection signal detected at the position of each vibration pickup 5 and the resonance frequency are displayed in a state where the worker 12 can compare and contrast. Is done. One mode of the display state is shown in FIGS. In these drawings, the solid line indicates the spectrum intensity, and → indicates the frequency (resonance frequency) derived by the resonance frequency deriving means 33. On the other hand, at the same time, in the judgment means, the peak position P of the spectrum is compared with a separately determined resonance frequency, and if a coincident frequency exists, the peak position P is at a position corresponding to the position of the vibration pickup 5. The determination that the piping member 1a is highly likely to be the corresponding piping member 1a in frequency is output.

Hereinafter, the working procedure will be specifically described. 1 The worker 12 arrives at a work site 13 as shown in FIG. At this point, a burying map indicating the burying position of the gas pipe 1 near the site is prepared. Therefore, the approximate buried position and direction of the pipe 1 are known in advance. Further, the structure (information including the inner diameter) of the plurality of pipe members 1a constituting the pipe is known in advance. If such information is difficult to obtain, use an underground radar (not shown)
The position of the pipe 1 is confirmed, and the pipe 1 is located at least above the buried pipe on the ground side. Further, with respect to the type of gas in the pipe and the pressure and temperature thereof, for example, whether or not city gas is supplied, and measurement results of the pressure and temperature in the pipe are obtained. The gas type, pipe pressure, temperature, and the like obtained in this manner are input to the exploration apparatus 2, and the resonance frequencies for the plurality of pipe members 1 a can be obtained in advance by the resonance frequency deriving unit 33. 2. A gas meter (not shown) of a specific home 7 is removed from the standpipe 11, and the speaker 4 is attached to the end 6. 3. On the other hand, a plurality of ground-side vibration pickups 5a are arranged at positions on the buried pipe that are known in advance. 4. After completing such a preparation stage, the Qingdao pulse generating means 31 operates to cause the speaker 4 to transmit the Qingdao pulse sound (band 0 to 10 kHz) into the tube. 5. The Qingdao pulse sound propagating in the pipe is sequentially propagated in a direction away from the speaker 4 on the sound emitting side. In this state, on the ground side, the detected-wave sound receiving data is collected by the front-side vibration pickups 5a arranged at the positions on the pipes along the installation direction. 6 The detection signal detected by the ground side vibration pickup 5a is sent to the exploration device main body 3, and the frequency analysis means 3
2, the spectrum intensity is specified as the spectrum data as shown in FIGS. 7. Then, the resonance frequency information obtained as described above and the spectrum of the detection signal detected by each vibration pickup are sent to the display device 37 provided in the exploration apparatus main body 3, and the operator visually confirms it. it can. On the other hand, when the spectrum has a peak portion P, when the frequency of the peak portion P and the resonance frequency obtained separately overlap, the specific pipe member corresponding to the frequency is located at the corresponding pipe portion at the sound receiving position. The estimation data indicating that the pipe member is a certain pipe member is output by the judging means 35.

The results of verification that can take the above method will be described below. FIG. 2 shows the structure of the piping used for the verification. The pipes consist of five 100A cast iron tubes A1, A
2, A3, and A4 were connected by four sleeve joints C, and the pipe 1 was buried at a buried depth of 50 cm. FIG. 3A shows the measurement result immediately above the ground portion (ground surface) of the 100A cast iron pipe indicated by A2 in the figure.
Looking at the frequency characteristics of the detected sound at this position,
Resonance occurs at 0 Hz, which agrees with the theoretical value in the case of a pipe radius of 0.05 m and air. FIG. 3B shows the frequency characteristics of the vibration on the ground surface at a position moved 80 cm from the center of the sleeve joint C to the side A2. In this result, together with the resonance of the tube, a peak P appears on the lower side of this frequency by one step, and it can be understood from the relationship with the inner diameter of the joint that the peak P is caused by the joint. As shown in FIG.
6 shows the frequency characteristics of the detected sound just above the sleeve joint C (the ground surface). Resonance occurs around 1500 Hz different from FIG. This resonance frequency does not match the theoretical value of the cast iron tube. The decrease in the resonance frequency means an increase in the apparent tube diameter, which coincides with the shape (expanded diameter) of the sleeve joint C.

[Other Embodiments] (A) In the above embodiment, the Qingdao pulse sound was used. However, in the application of the present invention, a pulse sound composed of sounds of a plurality of frequency components is used. , Any sound can be used. Further, for example, it is preferable to use a sound including almost all frequency components called so-called impulse sound and white noise. Further, a rectangular wave or a triangular wave that emits a sound wave only during a predetermined time period can be used. The above-described resonance frequency has mainly been described with reference to the center frequency. However, such a resonance frequency means all or any of the resonance frequencies required in a situation in the field. May be. Further, it is assumed that the resonance frequency has a predetermined band range. (B) In the above embodiment, the structure of the piping is searched from the peak position (resonance frequency) in the spectrum of the detected wave (including sound) in the frequency analysis result. Instead, the piping structure can be confirmed by observing an increase in the spectrum intensity (detection level) in a specific frequency band. That is, for example, when a plurality of pipes having different pipe diameters are connected, a peak is formed at a frequency portion depending on the pipe diameter,
When a bent pipe having a large diameter is connected to a predetermined straight pipe, the resonance frequency shifts with an increase in the diameter, and a predetermined band (predetermined frequency band) associated with the bending structure is observed. A band-like increase in spectral intensity can be found. For example, in the example corresponding to FIG. 3C, if the joint has a bent shape,
You can find the peak drop around. Therefore, in this way, it is possible to determine whether the pipe is a bent pipe and furthermore, whether or not the pipe is expanded. Therefore, in the method of the present invention, at least a straight pipe having a different pipe diameter, identification of a straight pipe, a bent pipe, and the like can be determined. (C) In the above embodiment, the structure in which sound waves are positively sent into the pipe to be searched has been described. However, for example, a gas flow is present in the pipe, and noise caused by this flow is transmitted to the in-pipe traveling vehicle. This noise can be used, for example, when it can be detected by a detection device provided. That is, such a noise contains an acoustic component representing the structure of the tube at the detection position. That is, by detecting this noise and performing frequency analysis to obtain a spectrum of the noise, it is possible to detect a resonance frequency component based on a tube diameter or the like at the detection position. Therefore, by detecting such a component, the structure of the tube can be clarified.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a state in which the structure of a gas pipe is being explored using the pipeline inspection device of the present application.

FIG. 2 is a diagram showing a state of a gas pipe used for verification.

FIG. 3 is a diagram showing a frequency analysis result of a propagation sound from various parts of a pipe;

FIG. 4 is an explanatory diagram of a vibration pattern corresponding to each mode.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gas pipe 2 Exploration apparatus 4 Speaker 5 Vibration pickup 5a Ground vibration pickup 32 Frequency analysis means 33 Resonance frequency derivation means 34 Display device 35 Judgment means

Continued on the front page (72) Inventor Seiichi Ito 4-1-2 Hirano-cho, Chuo-ku, Osaka-shi, Osaka Inside Osaka Gas Co., Ltd. (72) Inventor Masaki Kishi 4-1-2, Hirano-cho, Chuo-ku, Osaka-shi, Osaka No. Osaka Gas Co., Ltd. (72) Inventor Masao Aoki 1-3-7301 Migatadai, Nishi-ku, Kobe-shi, Hyogo F-term (reference) 2D063 BA00 5J083 AA04 AB12 AC05 AD07 AE10 AF04 BA01 BA14 BE11 BE43 CA02 EB04

Claims (6)

[Claims] 1. A method for exploring a piping structure in which a structure of a piping is searched from outside a coating layer in which the piping is provided, wherein a sound wave is propagated in the piping, and a sound is transmitted from the piping outside the coating layer. A pipe for detecting a propagating wave propagating through the coating layer, performing a frequency analysis of the detected detection wave, and exploring a pipe structure at a pipe portion corresponding to a detection position from the obtained frequency analysis result. How to explore the structure. 2. When the pipe is composed of a plurality of pipe members having different inner diameters, a resonance frequency of a medium in the pipe member is obtained from an inner diameter of the plurality of pipe members and a sound velocity of a medium existing in the pipe. A method for searching a piping structure for identifying a piping member at a piping portion corresponding to the detected position in correspondence with a peak position or a detection level in the obtained frequency analysis result. 3. A method for exploring a pipe structure for exploring a structure of a pipe, wherein a sound wave is propagated in the pipe, and a propagation sound propagated at a search position in the pipe different from a sound source of the sound wave. And a frequency analysis of the detected sound, and a piping structure exploring method for exploring a piping structure at the exploration position from an obtained frequency analysis result. 4. A device comprising a sound transmitting device and a vibration wave detecting device, based on diameter-related information relating to a plurality of pipe members constituting a pipe to be searched and sound speed information of a medium present in the pipe. A resonance frequency deriving unit that obtains a resonance frequency of a medium in each of the pipe members; and a frequency analysis unit that performs a frequency analysis of a detection wave detected by the detection device. Frequency analysis result obtained by
A piping exploration apparatus including an output unit that outputs each resonance frequency obtained for each piping member by the resonance frequency deriving unit in association with each other. 5. A device comprising a sound transmitting device and a vibration wave detecting device, based on diameter-related information on a plurality of pipe members constituting a pipe to be searched and sound speed information of a medium present in the pipe. A resonance frequency deriving unit that obtains a resonance frequency of a medium in each of the pipe members; and a frequency analysis unit that performs a frequency analysis of a detection wave detected by the detection device. When the peak position in the frequency analysis result obtained by the above is any one of the resonance frequencies obtained for each pipe member by the resonance frequency deriving means, a pipe portion corresponding to the detection position for detecting the detection wave is And an exploration apparatus provided with a judging means for judging that there is a high possibility that the pipe member corresponds to the resonance frequency. 6. A method for exploring a pipe structure for exploring a structure of a pipe, wherein a propagation sound propagating in the pipe is detected at a search position,
A method for exploring a piping structure, wherein a frequency analysis of a detected sound is performed, and a structure of the piping at the exploration position is explored from a frequency analysis result obtained.