JPH0933379A - Method for inspecting pipe by electromagnetic wave - Google Patents

Method for inspecting pipe by electromagnetic wave

Info

Publication number
JPH0933379A
JPH0933379A JP17918595A JP17918595A JPH0933379A JP H0933379 A JPH0933379 A JP H0933379A JP 17918595 A JP17918595 A JP 17918595A JP 17918595 A JP17918595 A JP 17918595A JP H0933379 A JPH0933379 A JP H0933379A
Authority
JP
Japan
Prior art keywords
pipe
electromagnetic wave
electromagnetic waves
inspected
antenna
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP17918595A
Other languages
Japanese (ja)
Inventor
Kiichi Suyama
毅一 陶山
Takashi Imaoka
隆司 今岡
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Tokyo Gas Co Ltd
Original Assignee
Tokyo Gas Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Tokyo Gas Co Ltd filed Critical Tokyo Gas Co Ltd
Priority to JP17918595A priority Critical patent/JPH0933379A/en
Priority to KR1019960704397A priority patent/KR100233954B1/en
Priority to DE69526213T priority patent/DE69526213T2/en
Priority to CN95191631A priority patent/CN1108521C/en
Priority to PCT/JP1995/002604 priority patent/WO1996018884A1/en
Priority to US08/687,450 priority patent/US6008657A/en
Priority to EP95940470A priority patent/EP0745841B1/en
Priority to CA002180857A priority patent/CA2180857C/en
Publication of JPH0933379A publication Critical patent/JPH0933379A/en
Priority to US09/048,117 priority patent/US6005396A/en
Priority to US09/047,932 priority patent/US6008658A/en
Priority to US09/048,115 priority patent/US5990690A/en
Priority to US09/048,116 priority patent/US5966016A/en
Priority to US09/048,002 priority patent/US5963042A/en
Priority to CN03102911A priority patent/CN1431487A/en
Priority to CN03102910A priority patent/CN1431486A/en
Pending legal-status Critical Current

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Abstract

PROBLEM TO BE SOLVED: To improve the detecting precision and working easiness in the detection of a leakage position such as corroded hole generated in a pipe such as gas pipe by use of electromagnetic waves. SOLUTION: A number of emitting parts having directivity in the direction orthogonal to an axis are connected in the axial direction into a long form. For example, a long transmitting antenna 9 such as leakage coaxial cable is inserted to a range to be inspected of a pipe 1 to emit an electromagnetic wave from the inner part of the pipe, and the electromagnetic wave 7 leaked from a leakage position 6 such as a hole of the pipe to the outside is probed and received while receiving antenna 4 is moved along the pipe within the range to be inspected, thereby, the leakage position of the pipe is detected. The leakage position of the pipe can be detected by using an electromagnetic wave having a frequency lower than the cutoff frequency of the electromagnetic wave as the circular waveguide of the pipe, and when a buried pipe is inspected, the influence of the attenuation of electromagnetic wave by earth and concrete an be reduced. Since the synchronous movement of the transmitting and receiving antennas is not needed, the labor on field construction is reduced, and the generation of an inspection error is also reduced.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は電磁波を利用してガス管
等の管に生じた腐食孔等の漏洩個所を検出する検査方法
に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inspection method for detecting leak points such as corrosion holes formed in a gas pipe by using electromagnetic waves.

【０００２】[0002]

【従来の技術】ガス管に生じた腐食孔等の漏洩個所を検
出する方法の一つとして、電磁波を利用した検出方法が
提案されている。この電磁波を利用した検査方法の第１
の方法として、図２に示すように金属製のガス管１の適
所を切断して取り付けた励振部２から送信装置３により
電磁波を励振して円形導波管と同様な態様で検査対象範
囲を伝播させ、外部において受信アンテナ４を検査対象
範囲のガス管１に沿って移動させながら漏洩個所６から
漏れてくる電磁波７を探査して、受信装置５により受信
することにより漏洩個所６を検出する方法がある。また
電磁波を利用した検査方法の第２の方法として、第１の
方法のようにガス管に電磁波を励磁するのではなく、送
信アンテナ８を、検査対象範囲のガス管１内に移動さ
せ、これと同時に受信アンテナ４を検査対象範囲の管に
沿って移動させながら漏洩個所６から漏れてくる電磁波
７を探査して、受信装置５で受信することにより漏洩個
所６を検出する方法がある。2. Description of the Related Art As one of methods for detecting a leaked portion such as a corrosion hole formed in a gas pipe, a detection method using electromagnetic waves has been proposed. The first inspection method using this electromagnetic wave
As shown in FIG. 2, as shown in FIG. 2, the electromagnetic wave is excited by the transmitter 3 from the exciter 2 which is attached by cutting the metal gas pipe 1 at an appropriate position, and the inspection target range is set in the same manner as the circular waveguide. While propagating and moving the receiving antenna 4 along the gas pipe 1 in the range to be inspected outside, the electromagnetic wave 7 leaking from the leaking point 6 is searched, and the leaking point 6 is detected by being received by the receiving device 5. There is a way. As a second method of the inspection method using electromagnetic waves, instead of exciting the electromagnetic waves in the gas pipe as in the first method, the transmitting antenna 8 is moved into the gas pipe 1 in the inspection target range, At the same time, there is a method in which the electromagnetic wave 7 leaking from the leaking point 6 is searched while the receiving antenna 4 is moved along the pipe in the inspection target range, and the leaking point 6 is detected by being received by the receiving device 5.

【０００３】[0003]

【発明が解決しようとする課題】第１の方法では、円形
導波管としてのカットオフ周波数以下の周波数の電磁波
をガス管に伝播させることができないので、埋設管等の
検査において土やコンクリート等による減衰量を低減す
るため周波数を低下させようとしてもできない場合があ
る。第２の方法では、送信アンテナと受信アンテナを同
期させて移動させることが困難であり、特に、送信アン
テナの場合は円滑な移動が困難である。そこで本発明
は、このような課題を解決することを目的とするもので
ある。In the first method, electromagnetic waves having a frequency lower than the cut-off frequency of the circular waveguide cannot be propagated to the gas pipe, so that soil, concrete or the like can be used for inspection of buried pipes. It may not be possible to reduce the frequency in order to reduce the amount of attenuation due to. According to the second method, it is difficult to move the transmitting antenna and the receiving antenna in synchronization with each other, and particularly in the case of the transmitting antenna, smooth movement is difficult. Then, this invention aims at solving such a subject.

【０００４】[0004]

【課題を解決するための手段】上述した課題を解決する
ために、本発明では、軸と直交する方向に指向性を有す
る多数の放射部を軸方向に連ねて長尺に構成した送信ア
ンテナを管の検査対象の範囲に挿入して管内から電磁波
を放射すると共に外部において受信アンテナを上記検査
対象範囲の管に沿って移動させながら、管の孔等の漏洩
個所から外部に漏洩する電磁波を探査し、受信すること
により、管の漏洩個所を検出することを提案する。In order to solve the above-mentioned problems, according to the present invention, there is provided a transmitting antenna having a long length in which a large number of radiating portions having directivity in a direction orthogonal to an axis are connected in the axial direction. While radiating electromagnetic waves from the inside of the pipe by inserting it into the inspection target area of the pipe, while moving the receiving antenna along the pipe in the above inspection target range, search for electromagnetic waves leaking outside from leakage points such as holes in the pipe Then, it is proposed to detect the leaked part of the pipe by receiving it.

【０００５】そして本発明では、上記の構成において、
送信アンテナは、指向性を軸と直交する方向に調節した
長尺のヘリカルアンテナとしたり、又は漏れ同軸ケーブ
ルとしたり、又はより対形漏れケーブルとすることを提
案する。In the present invention, in the above structure,
It is proposed that the transmitting antenna be a long helical antenna whose directivity is adjusted in a direction orthogonal to the axis, a leaky coaxial cable, or a twisted pair leaky cable.

【０００６】[0006]

【作用】軸と直交する方向に指向性を有する多数の放射
部が軸方向に連なった長尺の送信アンテナを管の検査対
象範囲に挿入して、夫々の放射部から電磁波を放射する
ので、受信アンテナ側のみを検査対象範囲の管に沿って
移動させて、漏洩する電磁波の探査を行うことができ
る。電磁波は、円形導波管として管内を伝播させる必要
がないので、使用できる周波数は円形導波管としてのカ
ットオフ周波数以上に制限されない。Since a long transmitting antenna in which a large number of radiating parts having directivity in the direction orthogonal to the axis are continuous in the axial direction is inserted into the inspection target range of the pipe and electromagnetic waves are radiated from the respective radiating parts, Only the receiving antenna side can be moved along the pipe in the inspection range to detect leaking electromagnetic waves. Since the electromagnetic wave does not have to propagate inside the tube as a circular waveguide, the usable frequency is not limited to the cutoff frequency as a circular waveguide or more.

【０００７】[0007]

【実施例】次に本発明の実施例を添付図面を参照して説
明する。図１は本発明の方法をガス管の漏洩個所検出に
適用した実施例の全体構成を模式的に示すものであり、
図１、図２の構成要素と同様なものには同一の符号を付
して説明は省略する。本発明では、上述したとおり、軸
と直交する方向に指向性を有する多数の放射部が軸方向
に連なった長尺の送信アンテナ９を対象とするガス管１
の検査対象範囲に挿入して、これらの放射部から電磁波
を放射し、この状態において受信アンテナ４と受信装置
５を検査対象範囲のガス管１に沿って移動させて、漏洩
する電磁波７の探査を行う。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 schematically shows the overall configuration of an embodiment in which the method of the present invention is applied to detection of a leak location in a gas pipe,
The same components as those in FIGS. 1 and 2 are designated by the same reference numerals and the description thereof will be omitted. In the present invention, as described above, the gas pipe 1 for the long transmission antenna 9 in which a large number of radiation portions having directivity in the direction orthogonal to the axis are connected in the axial direction.
Of the electromagnetic wave emitted from these radiating parts, and in this state, the receiving antenna 4 and the receiving device 5 are moved along the gas pipe 1 in the range to be inspected to search for the leaking electromagnetic wave 7. I do.

【０００８】本発明において使用する長尺の送信アンテ
ナ９の例としては、移動体通信用として利用されている
漏れ同軸ケーブルや、より対形漏れケーブルを利用する
ことができ、このようなケーブルは、従来から広く使用
されている管内探査機器等の駆動用ケーブルをガス管の
活き状態で移動可能な挿入機構等を利用してガス管１内
に挿入することができる。As an example of the long transmitting antenna 9 used in the present invention, a leaky coaxial cable used for mobile communication or a twisted pair leaky cable can be used. It is possible to insert a drive cable for a pipe exploration device or the like which has been widely used from the past into the gas pipe 1 by using an insertion mechanism or the like which can be moved in a live state of the gas pipe.

【０００９】この他、長尺の送信アンテナ９としては、
ヘリカル線１巻の長さを、放射すべき電磁波の波長より
も極めて小さくしたり、又は波長のｎ倍（ｎは２以上の
整数）として指向性を軸と直交する方向に調節したヘリ
カルアンテナを長尺に配設して構成することができ、ヘ
リカル線を絶縁物で被覆してケーブル状に構成すること
により、上述したケーブルと同様な取扱を行うことがで
きる。In addition to this, as the long transmission antenna 9,
A helical antenna in which the length of one turn of the helical wire is made extremely smaller than the wavelength of the electromagnetic wave to be radiated or n times the wavelength (n is an integer of 2 or more) is used to adjust the directivity in the direction orthogonal to the axis. It can be arranged in a long length and can be handled in the same manner as the above-mentioned cable by covering the helical wire with an insulator to form a cable.

【００１０】以上の他、送信アンテナ９は、多数の小ア
ンテナをケーブル状に連設して構成する等の適宜の構成
とすることができる。In addition to the above, the transmitting antenna 9 may have an appropriate structure such as a large number of small antennas connected in a cable.

【００１１】また以上の実施例では、検査の対象をガス
管としているが、本発明は、ガス管の他、適宜の金属製
の管を検査対象とすることができるものである。Further, in the above embodiments, the object of inspection is a gas pipe, but the present invention can be applied to an appropriate metal pipe in addition to the gas pipe.

【００１２】[0012]

【発明の効果】本発明は以上のとおりであるので、電磁
波を利用してガス管等の管に生じた腐食孔等の漏洩個所
を検出する検査方法において、次のような効果がある。 管の円形導波管としての電磁波のカットオフ周波数以
下の周波数の電磁波を利用して漏洩個所の検出を行うこ
とができ、埋設管を対象とする場合、土、コンクリート
による電磁波の減衰の影響を低減することができる。 送、受信アンテナを同期させて移動させる必要がない
ので、現場施工上の労力を低減することができると共
に、検査ミス等の発生を低減することができる。As described above, the present invention has the following effects in an inspection method for detecting leak points such as corrosion holes formed in gas pipes using electromagnetic waves. The leak point can be detected by using the electromagnetic wave with a frequency lower than the cutoff frequency of the electromagnetic wave as the circular waveguide of the pipe, and when the buried pipe is targeted, the influence of the attenuation of the electromagnetic wave by the soil and concrete can be considered. It can be reduced. Since it is not necessary to move the transmitting and receiving antennas in synchronism with each other, it is possible to reduce the labor on site construction and reduce the occurrence of inspection errors and the like.

【図面の簡単な説明】[Brief description of drawings]

【図１】 本発明の方法をガス管の漏洩個所検出に適用
した実施例の全体構成の模式図である。FIG. 1 is a schematic diagram of an overall configuration of an embodiment in which the method of the present invention is applied to detection of a leak point in a gas pipe.

【図２】 電磁波を利用した従来の、ガス管の漏洩個所
検出方法の一例の全体構成を示す模式図である。FIG. 2 is a schematic diagram showing an overall configuration of an example of a conventional method for detecting a leaked portion of a gas pipe using electromagnetic waves.

【図３】 電磁波を利用した従来の、ガス管の漏洩個所
検出方法の他例の全体構成を示す模式図である。FIG. 3 is a schematic diagram showing an entire configuration of another example of a conventional leak detection method for a gas pipe using electromagnetic waves.

【符号の説明】[Explanation of symbols]

１ ガス管 ２ 励振部 ３ 送信装置 ４ 受信アンテナ ５ 受信装置 ６ 漏洩個所 ７ 漏洩電磁波 ８ 送信アンテナ ９ 長尺送信アンテナ 1 Gas Pipe 2 Excitation Unit 3 Transmitter 4 Receiving Antenna 5 Receiving Device 6 Receiving Point 6 Leakage Electromagnetic Wave 8 Transmitting Antenna 9 Long Transmitting Antenna

Claims (4)

【特許請求の範囲】[Claims] 【請求項１】 軸と直交する方向に指向性を有する多数
の放射部を軸方向に連ねて長尺に構成した送信アンテナ
を管の検査対象の範囲に挿入して管内から電磁波を放射
すると共に外部において受信アンテナを上記検査対象範
囲の管に沿って移動させながら、管の孔等の漏洩個所か
ら外部に漏洩する電磁波を探査し、受信することによ
り、管の漏洩個所を検出することを特徴とする電磁波に
よる管の検査方法1. A transmission antenna having a long length in which a large number of radiating portions having directivity in a direction orthogonal to an axis are connected in the axial direction is inserted into a range of a pipe to be inspected, and electromagnetic waves are radiated from the inside of the pipe. While moving the receiving antenna along the pipe in the range to be inspected externally, the leaking point of the pipe is detected by searching and receiving the electromagnetic wave leaking outside from the leaking point such as the hole of the pipe. Method of inspecting tubes with electromagnetic waves 【請求項２】 送信アンテナは、指向性を軸と直交する
方向に調節した長尺のヘリカルアンテナとしたことを特
徴とする請求項１記載の電磁波による管の検査方法2. The method for inspecting a pipe by electromagnetic waves according to claim 1, wherein the transmitting antenna is a long helical antenna whose directivity is adjusted in a direction orthogonal to the axis. 【請求項３】 送信アンテナは、漏れ同軸ケーブルとし
たことを特徴とする請求項１記載の電磁波による管の検
査方法3. The method for inspecting a pipe by electromagnetic waves according to claim 1, wherein the transmitting antenna is a leaky coaxial cable. 【請求項４】 送信アンテナは、より対形漏れケーブル
としたことを特徴とする請求項１記載の電磁波による管
の検査方法4. The method for inspecting a pipe by electromagnetic waves according to claim 1, wherein the transmitting antenna is a twisted pair leak cable.
JP17918595A 1994-12-16 1995-07-14 Method for inspecting pipe by electromagnetic wave Pending JPH0933379A (en)

Priority Applications (15)

Application Number Priority Date Filing Date Title
JP17918595A JPH0933379A (en) 1995-07-14 1995-07-14 Method for inspecting pipe by electromagnetic wave
EP95940470A EP0745841B1 (en) 1994-12-16 1995-12-18 A method and apparatus for inspecting a pipe using electromagnetic radiation
CA002180857A CA2180857C (en) 1994-12-16 1995-12-18 A method for inspecting the elements of piping systems by electromagnetic waves
DE69526213T DE69526213T2 (en) 1994-12-16 1995-12-18 METHOD AND DEVICE FOR INSPECTING A TUBE WITH ELECTROMAGNETIC RADIATION
CN95191631A CN1108521C (en) 1994-12-16 1995-12-18 Electromagnetic inspection of elements of piping
PCT/JP1995/002604 WO1996018884A1 (en) 1994-12-16 1995-12-18 Electromagnetic inspection of elements of piping
US08/687,450 US6008657A (en) 1994-12-16 1995-12-18 Method for inspecting the elements of piping systems by electromagnetic waves
KR1019960704397A KR100233954B1 (en) 1994-12-16 1995-12-18 Electromagnetic inspection of elements of piping
US09/048,117 US6005396A (en) 1994-12-16 1998-03-26 Method for inspecting the elements of piping systems by electromagnetic waves
US09/048,002 US5963042A (en) 1994-12-16 1998-03-26 Method for inspecting the elements of piping systems by electromagnetic waves
US09/047,932 US6008658A (en) 1994-12-16 1998-03-26 Method for inspecting the elements of piping systems by electromagnetic waves
US09/048,115 US5990690A (en) 1994-12-16 1998-03-26 Method for inspecting the elements of piping systems BT electromagnetic waves
US09/048,116 US5966016A (en) 1994-12-16 1998-03-26 Method for inspecting the elements of piping systems by electromagnetic waves
CN03102911A CN1431487A (en) 1994-12-16 2003-01-21 Electromagnetic wave checking method for duct system
CN03102910A CN1431486A (en) 1994-12-16 2003-01-21 Electromagnetic wave checking method for duct system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP17918595A JPH0933379A (en) 1995-07-14 1995-07-14 Method for inspecting pipe by electromagnetic wave

Publications (1)

Publication Number Publication Date
JPH0933379A true JPH0933379A (en) 1997-02-07

Family

ID=16061431

Family Applications (1)

Application Number Title Priority Date Filing Date
JP17918595A Pending JPH0933379A (en) 1994-12-16 1995-07-14 Method for inspecting pipe by electromagnetic wave

Country Status (1)

Country Link
JP (1) JPH0933379A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006049303A1 (en) * 2004-11-08 2006-05-11 Sakae Co., Ltd. Method and device for inspecting filling of grout in sheath tube
JP2009511884A (en) * 2005-10-12 2009-03-19 エアバス・ドイチュラント・ゲーエムベーハー Leak detector

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006049303A1 (en) * 2004-11-08 2006-05-11 Sakae Co., Ltd. Method and device for inspecting filling of grout in sheath tube
JP2009511884A (en) * 2005-10-12 2009-03-19 エアバス・ドイチュラント・ゲーエムベーハー Leak detector
US8365581B2 (en) 2005-10-12 2013-02-05 Airbus Operations Gmbh Valve for a leak detector

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