JP3926668B2 - Pipe breakage detector - Google Patents

Pipe breakage detector Download PDF

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Publication number
JP3926668B2
JP3926668B2 JP2002122264A JP2002122264A JP3926668B2 JP 3926668 B2 JP3926668 B2 JP 3926668B2 JP 2002122264 A JP2002122264 A JP 2002122264A JP 2002122264 A JP2002122264 A JP 2002122264A JP 3926668 B2 JP3926668 B2 JP 3926668B2
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Japan
Prior art keywords
sound
pipe
value
detected
output devices
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JP2002122264A
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Japanese (ja)
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JP2003315319A (en
Inventor
裕一 森川
明彦 江波戸
義之 佐藤
武司 戸井
江平 藤川
信行 大久保
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Toshiba Corp
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Toshiba Corp
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  • Examining Or Testing Airtightness (AREA)
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Description

【0001】
【発明の属する技術分野】
本発明は、例えばガス管などのごとき配管の破損位置を検出する配管破損検出装置に係り、さらに詳細には、音波の腹の部分が配管の破損部分に合致すると音圧変化が大きいことを利用して配管の破損位置を検出する配管破損検出装置に関する。
【0002】
【従来の技術】
従来、例えば工場、発電所、市中等に設置されているガス管、水道管等の配管の破損位置の検出は、作業員による聴診、ハンマリング等の手作業によって一般的に行われている。
【0003】
【発明が解決しようとする課題】
従来のごとく、作業員による手作業によって配管の破損位置を検出する場合は、作業員の熟練度を要することは勿論のこと、配管の破損検査期間の合間に不測の事態が発生した場合には、そのまま配管の破損が発見されないことがある等の問題がある。
【0004】
【課題を解決するための手段】
本発明は、前述のごとき従来の問題に鑑みてなされたもので、請求項1に係る発明は、配管内部に音波を供給可能なように配置された複数の音響出力装置と、前記配管内部に当該配管の長手方向の音波が検出可能なように適宜間隔に配置された複数の音検出センサと、前記複数の音響出力装置から位相の異なる音波を出力すべく前記複数の音響出力装置の出力を制御する位相可変信号発生装置と、前記配管の正常時に前記各音検出センサで検出した検出値を基準値として記憶した記憶装置と、検査時に検出した前記各音検出センサの検出値と前記記憶装置に記憶した各音検出センサの基準値とを比較して前記配管の破損位置を判定する破損位置判定部と、を備えた構成である。
【0005】
請求項2に係る発明は、請求項1に記載の配管破損検出装置において、前記破損位置判定部は、前記各音響出力装置から出力された音波の位相差毎に、前記音検出センサの基準値と検出値との差の絶対値を演算して平均値を算出し、この算出した平均値の最小値に該当する前記音波の位相差で前記各音検出センサの前記基準値と検出値との差を求め、この求めた差の最小の音検出センサの位置付近を配管の破損位置として検出する構成である。
【0006】
【発明の実施の形態】
図1を参照するに、本発明の実施の形態に係る配管破損検出装置1は、配管3内に配置されたスピーカ等のごとき複数の音響出力装置5A,5Bを備えると共に、前記配管3内に、当該配管3の長手方向に適宜間隔に配置したマイク等のごとき複数の音検出センサS1〜S8を備えている。
【0007】
そして、前記各音響出力装置5A,5Bには、各音響出力装置5A,5Bから位相の異なる音波を出力すべく前記各音響出力装置5A,5Bの出力を制御自在の位相可変信号発生装置7が接続してある。また前記各音検出センサS1〜S8には、各音検出センサS1〜S8によって検出した音圧の検出値を信号処理し記憶する記憶装置9が接続してある。
【0008】
前記記憶装置9は、前記配管3が正常なときに前記各音響出力装置5A,5Bから種々位相を異にして音波を出力し、前記各音検出センサS1〜S8によって音圧を検出したときの各検出値を、各位相毎に各音検出センサS1〜S8の基準値として予め記憶すると共に、前記配管3の破損検出のために前記各音響出力装置5A,5Bから種々位相を異にして音波を出力したときの各音検出センサS1〜S8の各検出値を記憶するものである。
【0009】
上記記憶装置9には破損位置判定部11が接続してあり、この破損位置判定部11には表示部13が接続してある。上記破損位置判定部11は、前記記憶部9に予め格納されている基準値と破損検査時に各音検出センサS1〜S8によって検出した音圧の検出値とを比較して前記配管3の破損位置を判定するもので、その判定結果は前記表示部13に表示されるものである。
【0010】
前記位相可変信号発生装置7及び前記記憶装置9には、上記両装置7,9を制御する計測制御装置15が接続してある。
【0011】
以上のごとき構成において、配管3に損傷や破損、欠損等が生じていない正常な状態にあるときに、上記配管3内に配置した複数の音響出力装置5A,5Bから位相差0の音波を出力し、このときに前記配管3内に配置した各音検知センサS1〜S8によって検出した音圧の各検出値を、位相差0時の基準値として記憶装置9に記憶する。
【0012】
次に、位相可変信号発生装置7の制御の下に前記各音響出力装置5A,5Bから出力する音波の位相差を例えば30度にして出力して合成し、この合成音波を生じたときに各音検知センサS1〜S8によって検出した音圧の検出値を、位相差30°のときの基準値として前記記憶装置9に記憶する。同様にして、各音響出力装置5A,5Bから出力される音波の位相が、例えば60°,90°,120°,150°及び180°のときの基準値を前記記憶装置9に格納する。
【0013】
すなわち、配管3が正常な場合において、各音響出力装置5A,5Bから各種の位相差でもって音波を出力したときの音響モードでの音圧分布を、前記各音検知センサS1〜S8によって測定し、基準データとして前記記憶装置9に予め格納するものである。
【0014】
その後、前記配管3の破損(欠損)検出時に、前述同様に、位相可変信号発生装置7の制御の下に各音響出力装置5A,5Bから各種の位相差でもって音波を出力し、各種の音響モードにおいて各音検出センサS1〜S8によって音圧分布を検出し、各音検知センサS1〜S8の検出値を前記記憶装置9に格納する。そして、例えば各音響出力装置5A,5Bから出力された音波の位相差0のときの各音検出センサS1〜S8の検出値を位相差0時における各音検出センサS1〜S8の前記基準値との差の絶対値を前記破損位置判定部9において演算し、かつ平均値を算出する。
【0015】
同様にして、各音響出力装置5A,5Bから出力される音波の位相差が例えば30°,60°,90°,120°,150°及び180°の各位相差毎に検出値と基準値との差の絶対値を演算しかつその平均値を算出する。
【0016】
上述のごとき処理結果を表示部13に表示するに、まず、各音響出力装置5A,5Bから位相差0で音波を出力したときの正常時の各音検出センサS1〜S8の検出値(基準値)及び音検出センサS3付近に試験的に穴等をあけてリーク有りの状態の破損状態とした場合においての位相差0での各音検出センサS1〜S8の検出値を参考的にグラフ化すると、図2に示すようになった。この図2に示す状態では、配管3の破損位置は不明である。
【0017】
そこで、前記位相可変信号発生装置7の制御の下に、前記各音響出力装置5A,5Bから出力する音波の位相を異にした音響モードで、各音響出力装置5A,5Bから出力された両音波を合成する。そして、合成音波の音圧の大きな腹の部分が前記破損(欠損)位置に合致するように、前記各音響出力装置5A,5Bから出力する音波の位相を種々異にする。出力された音波の各位相差毎に各音検出センサS1〜S8の検出値と予め設定した基準値との差の絶対値を演算し、かつ平均化してグラフ化する際、最大値を1として正規化すると、図3に示す結果が得られた。
【0018】
図3より明らかなように、図3においての最小値は、各音響出力装置5A,5Bから出力した音波の位相差が60度のときであることが分かる。すなわち、前記各音響出力装置5A,5Bから出力する音波の位相差を60度として合成したときの合成音波の腹の部分が破損位置に合致したものとして検知できる。
【0019】
そこで、破損位置を検知するために、各音響出力装置5A,5Bから位相差60度でもって音波を出力したときの音圧分布を各音検出センサS1〜S8によって検出し、その検出値と位相差60度のときの各音検出センサS1〜S8の予め設定してある基準値との差を求めグラフ化すると、図4に示すごときグラフになる。そして、図4により、前記音圧差が最小の位置として音検出センサS3の位置が求められる。すなわち、音検出センサS3の位置付近が破損位置として検知される。
【0020】
ところで、配管3の破損位置は必ずしも音検出センサに正確に対応した位置とは限らず、配管3に配置した複数の音検出センサの間である場合もある。この場合、配管3の破損位置の両隣りに位置する音検出センサの音圧差が共に小さくなるので、上記両隣りの音検出センサの音圧差の大小に対応して補間を行うことにより、配置した音検出センサの間に破損位置が位置する場合であっても、破損(欠損)位置を容易に検出することが可能なものである。
【0021】
ところで、前記説明においては、複数の音響出力装置5A,5Bを配管3の遠く離れた位置に対向するように例示して説明したが、複数の音響出力装置5A,5Bは近接して配置することも可能である。また、配管3が屈曲している場合であっても、最初に基準値を検出してデータ化し、この基準データと比較することによって欠損位置を検知するものであるから、配管3が屈曲している場合でも欠損位置を容易に検知することができる。
【0022】
【発明の効果】
以上のごとき説明より理解されるように、本発明によれば、配管内に配置した複数の音響出力装置から位相を異にした音波を出力し、両音波の合成音波の節部分が配管の破損部分と合致したことを検知することによって配管の破損位置を検出するものであるから、配管の破損検査に熟練を要することなく所望時期に破損検査を自動的に行うことができ、前述したごとき従来の問題を解消し得るものである。
【図面の簡単な説明】
【図1】本発明の実施の形態に係る配管破損検出装置の概念的構成を示す説明図である。
【図2】音波の位相差0度での音圧分布状態を示す説明図である。
【図3】破損時と正常時の音圧差の位相差毎の平均値を示す説明図である。
【図4】位相差60度での音圧分布を示す説明図である。
【符号の説明】
1 配管破損検出装置
3 配管
5A,5B 音響出力装置
7 位相可変信号発生装置
9 記憶装置
11 破損位置判定部
13 表示部
15 計測制御装置
[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pipe breakage detecting device for detecting a breakage position of a pipe such as a gas pipe, and more specifically, utilizing the fact that the sound pressure change is large when the anti-node portion of the sonic wave matches the broken part of the pipe. The present invention relates to a pipe breakage detection device that detects a breakage position of a pipe.
[0002]
[Prior art]
Conventionally, for example, detection of a broken position of a pipe such as a gas pipe or a water pipe installed in a factory, a power plant, a city, or the like is generally performed by manual work such as auscultation or hammering by an operator.
[0003]
[Problems to be solved by the invention]
As in the past, when detecting a broken position of a pipe manually by an operator, not only the skill level of the worker is required, but also if an unexpected situation occurs between pipe damage inspection periods. As a result, there is a problem that the pipe breakage may not be found as it is.
[0004]
[Means for Solving the Problems]
The present invention has been made in view of the conventional problems as described above, and the invention according to claim 1 includes a plurality of acoustic output devices arranged so as to be able to supply sound waves inside the piping, and the piping. A plurality of sound detection sensors arranged at appropriate intervals so that sound waves in the longitudinal direction of the pipe can be detected, and outputs of the plurality of sound output devices to output sound waves having different phases from the plurality of sound output devices A phase variable signal generator to be controlled, a storage device that stores a detection value detected by each sound detection sensor when the piping is normal, as a reference value, a detection value of each sound detection sensor detected during inspection, and the storage device And a damage position determination unit that compares the reference value of each sound detection sensor stored in the above and determines the damage position of the pipe.
[0005]
According to a second aspect of the present invention, in the pipe breakage detecting device according to the first aspect, the breakage position determination unit is configured to generate a reference value of the sound detection sensor for each phase difference of sound waves output from the respective sound output devices. The absolute value of the difference between the detected value and the average value is calculated to calculate an average value, and the phase difference of the sound wave corresponding to the minimum value of the calculated average value between the reference value and the detected value of each sound detection sensor The difference is obtained, and the vicinity of the position of the sound detection sensor having the smallest obtained difference is detected as a damaged position of the pipe.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, a pipe breakage detection apparatus 1 according to an embodiment of the present invention includes a plurality of acoustic output devices 5 </ b> A and 5 </ b> B such as speakers arranged in a pipe 3, and the pipe 3 includes A plurality of sound detection sensors S1 to S8 such as microphones arranged at appropriate intervals in the longitudinal direction of the pipe 3 are provided.
[0007]
Each of the acoustic output devices 5A and 5B has a variable phase signal generator 7 that can control the outputs of the acoustic output devices 5A and 5B to output sound waves having different phases from the acoustic output devices 5A and 5B. Connected. The sound detection sensors S1 to S8 are connected to a storage device 9 for signal processing and storing the sound pressure detection values detected by the sound detection sensors S1 to S8.
[0008]
The storage device 9 outputs sound waves with different phases from the acoustic output devices 5A and 5B when the pipe 3 is normal, and detects the sound pressure by the sound detection sensors S1 to S8. Each detection value is stored in advance as a reference value of each sound detection sensor S1 to S8 for each phase, and the sound output device 5A, 5B has a different phase to detect sound waves for detecting damage to the pipe 3. Each detected value of each of the sound detection sensors S1 to S8 is stored.
[0009]
A damaged position determination unit 11 is connected to the storage device 9, and a display unit 13 is connected to the damaged position determination unit 11. The breakage position determination unit 11 compares the reference value stored in advance in the storage unit 9 with the sound pressure detection values detected by the sound detection sensors S1 to S8 during the breakage inspection, and the breakage position of the pipe 3 The determination result is displayed on the display unit 13.
[0010]
A measurement control device 15 for controlling the devices 7 and 9 is connected to the phase variable signal generator 7 and the storage device 9.
[0011]
In the configuration as described above, when the pipe 3 is in a normal state in which no damage, breakage, loss or the like has occurred, sound waves having a phase difference of 0 are output from the plurality of acoustic output devices 5A and 5B arranged in the pipe 3. At this time, each detected value of the sound pressure detected by each of the sound detection sensors S1 to S8 arranged in the pipe 3 is stored in the storage device 9 as a reference value when the phase difference is zero.
[0012]
Next, under the control of the phase variable signal generator 7, the phase difference between the sound waves output from the sound output devices 5A and 5B is set to, for example, 30 degrees, and synthesized. The detected value of the sound pressure detected by the sound detection sensors S1 to S8 is stored in the storage device 9 as a reference value when the phase difference is 30 °. Similarly, a reference value when the phase of the sound wave output from each of the acoustic output devices 5A and 5B is, for example, 60 °, 90 °, 120 °, 150 °, and 180 ° is stored in the storage device 9.
[0013]
That is, when the pipe 3 is normal, the sound pressure distribution in the acoustic mode when sound waves are output from the acoustic output devices 5A and 5B with various phase differences is measured by the sound detection sensors S1 to S8. The data is stored in advance in the storage device 9 as reference data.
[0014]
After that, when the breakage (deletion) of the pipe 3 is detected, sound waves are output with various phase differences from the acoustic output devices 5A and 5B under the control of the phase variable signal generator 7, as described above, In the mode, the sound pressure distribution is detected by the sound detection sensors S1 to S8, and the detection values of the sound detection sensors S1 to S8 are stored in the storage device 9. For example, the detection values of the sound detection sensors S1 to S8 when the phase difference between the sound waves output from the acoustic output devices 5A and 5B is zero are the reference values of the sound detection sensors S1 to S8 when the phase difference is zero. The absolute value of the difference is calculated by the breakage position determination unit 9 and an average value is calculated.
[0015]
Similarly, the phase difference between the sound waves output from the acoustic output devices 5A and 5B is, for example, 30 °, 60 °, 90 °, 120 °, 150 °, and 180 ° for each phase difference. The absolute value of the difference is calculated and the average value is calculated.
[0016]
In order to display the processing results as described above on the display unit 13, first, the detection values (reference values) of the sound detection sensors S1 to S8 at the normal time when sound waves are output from the sound output devices 5A and 5B with a phase difference of 0. ) And the detection values of each of the sound detection sensors S1 to S8 at a phase difference of 0 when a hole or the like is made in the vicinity of the sound detection sensor S3 so as to be in a damaged state with a leak. As shown in FIG. In the state shown in FIG. 2, the breakage position of the pipe 3 is unknown.
[0017]
Therefore, under the control of the phase variable signal generator 7, both acoustic waves output from the acoustic output devices 5A and 5B in an acoustic mode in which the phases of the acoustic waves output from the acoustic output devices 5A and 5B are different. Is synthesized. Then, the phases of the sound waves output from the respective sound output devices 5A and 5B are made different so that the belly portion where the sound pressure of the synthesized sound wave is large matches the breakage (deletion) position. For each phase difference of the output sound wave, the absolute value of the difference between the detection values of the sound detection sensors S1 to S8 and the preset reference value is calculated and averaged to obtain a maximum value of 1. As a result, the result shown in FIG. 3 was obtained.
[0018]
As is clear from FIG. 3, it can be seen that the minimum value in FIG. 3 is when the phase difference between the sound waves output from the sound output devices 5A and 5B is 60 degrees. That is, it is possible to detect that the antinode portion of the synthesized sound wave when the phase difference of the sound wave output from each of the sound output devices 5A and 5B is synthesized at 60 degrees matches the breakage position.
[0019]
Therefore, in order to detect the breakage position, the sound pressure distribution when each sound output device 5A, 5B outputs a sound wave with a phase difference of 60 degrees is detected by each sound detection sensor S1 to S8, and the detected value and level are detected. When the difference from the reference value set in advance for each of the sound detection sensors S1 to S8 when the phase difference is 60 degrees is obtained and graphed, a graph as shown in FIG. 4 is obtained. Then, according to FIG. 4, the position of the sound detection sensor S3 is obtained as the position where the sound pressure difference is minimum. That is, the vicinity of the position of the sound detection sensor S3 is detected as a damaged position.
[0020]
By the way, the breakage position of the pipe 3 is not necessarily the position corresponding to the sound detection sensor accurately, and may be between a plurality of sound detection sensors arranged in the pipe 3. In this case, since the sound pressure difference between the sound detection sensors located on both sides of the damaged position of the pipe 3 is reduced, the arrangement is performed by performing interpolation according to the magnitude of the sound pressure difference between the sound detection sensors on both sides. Even when the breakage position is located between the sound detection sensors, the breakage (deletion) position can be easily detected.
[0021]
By the way, in the above description, the plurality of sound output devices 5A and 5B have been exemplified and described so as to face far away positions of the pipe 3, but the plurality of sound output devices 5A and 5B are arranged close to each other. Is also possible. Even if the pipe 3 is bent, the reference value is first detected and converted into data, and the missing position is detected by comparing with the reference data. Even when it is present, the defect position can be easily detected.
[0022]
【The invention's effect】
As will be understood from the above description, according to the present invention, sound waves having different phases are output from a plurality of acoustic output devices arranged in the pipe, and the joint portion of the combined sound waves of both the sound waves is damaged in the pipe. Because it detects the breakage position of the pipe by detecting that it matches the part, it can automatically perform the breakage inspection at a desired time without requiring skill in the pipe breakage inspection. The problem can be solved.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a conceptual configuration of a pipe breakage detection apparatus according to an embodiment of the present invention.
FIG. 2 is an explanatory diagram showing a sound pressure distribution state when a sound wave has a phase difference of 0 degree.
FIG. 3 is an explanatory diagram showing an average value for each phase difference of a sound pressure difference at the time of breakage and normal time.
FIG. 4 is an explanatory diagram showing a sound pressure distribution at a phase difference of 60 degrees.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Piping breakage detection apparatus 3 Piping 5A, 5B Sound output device 7 Phase variable signal generation device 9 Memory | storage device 11 Damaged position determination part 13 Display part 15 Measurement control apparatus

Claims (2)

配管内部に音波を供給可能なように配置された複数の音響出力装置と、前記配管内部に当該配管の長手方向の音波が検出可能なように適宜間隔に配置された複数の音検出センサと、前記複数の音響出力装置から位相の異なる音波を出力すべく前記複数の音響出力装置の出力を制御する位相可変信号発生装置と、前記配管の正常時に前記各音検出センサで検出した検出値を基準値として記憶した記憶装置と、検査時に検出した前記各音検出センサの検出値と前記記憶装置に記憶した各音検出センサの基準値とを比較して前記配管の破損位置を判定する破損位置判定部と、を備えたことを特徴とする配管破損検出装置。A plurality of sound output devices arranged so as to be able to supply sound waves inside the pipe, and a plurality of sound detection sensors arranged at appropriate intervals so that sound waves in the longitudinal direction of the pipe can be detected inside the pipe, A phase variable signal generator for controlling the outputs of the plurality of sound output devices to output sound waves having different phases from the plurality of sound output devices, and a detection value detected by each sound detection sensor when the piping is normal Damage position determination for determining the damage position of the pipe by comparing the storage device stored as a value, the detection value of each sound detection sensor detected at the time of inspection with the reference value of each sound detection sensor stored in the storage device And a pipe breakage detecting device. 請求項1に記載の配管破損検出装置において、前記破損位置判定部は、前記各音響出力装置から出力された音波の位相差毎に、前記音検出センサの基準値と検出値との差の絶対値を演算して平均値を算出し、この算出した平均値の最小値に該当する前記音波の位相差で前記各音検出センサの前記基準値と検出値との差を求め、この求めた差の最小の音検出センサの位置付近を配管の破損位置として検出する構成であることを特徴とする配管破損検出装置。2. The pipe breakage detection device according to claim 1, wherein the breakage position determination unit calculates an absolute difference between a reference value and a detection value of the sound detection sensor for each phase difference of sound waves output from the sound output devices. An average value is calculated by calculating a value, and a difference between the reference value and the detection value of each sound detection sensor is obtained from the phase difference of the sound wave corresponding to the minimum value of the calculated average value. A pipe breakage detecting device characterized in that the vicinity of the minimum sound detection sensor position is detected as a pipe breakage position.
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