Defect analysis device, defect analysis method, and program

Patent metadata

Field	Value
Publication number	US-9804053-B2
Application number	US-201314431809-A
Country	US
Kind code	B2
Filing date	Sep 13, 2013
Priority date	Sep 28, 2012
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

The present invention provides a defect analysis device including: an excitation unit ( 107 ) that imparts vibrations of a plurality of frequencies to a fluid ( 110 ) flowing through a pipe ( 108 ); a first detector ( 106 ) that, when the excitation part ( 107 ) is imparting vibrations, detects vibrations emanating from the pipe ( 108 ); and a signal processing unit ( 101 ) that extracts a feature quantity from a vibration waveform acquired by the first detector ( 106 ), and uses the extracted feature quantity to estimate the extent of a defect formed in the pipe ( 108 ).

First claim

The invention claimed is:

1. A defect analysis device including:
vibration means for applying vibration with a plurality of frequency components to at least one of fluid flowing in a pipe and the pipe,
first detection means for detecting the vibration applied by the vibration means, and
signal processing means for extracting a feature amount from a vibration waveform acquired by the first detection means and for estimating a degree of defect formed in the pipe by using the extracted feature amount.

2. The defect analysis device according to claim 1 , wherein
the signal processing means extracts at least one of a peak frequency and a sharpness of a peak as the feature amount.

3. The defect analysis device according to claim 1 , wherein
the signal processing means estimates at least one of a size of a hole formed in the pipe and an amount of fluid which leaks to the outside of the pipe through the hole formed in the pipe as a degree of defect formed in the pipe.

4. The defect analysis device according to claim 1 , wherein
the defect analysis device further includes reference data storage means for storing reference data in which the feature amount is associated with information indicating the degree of defect formed in the pipe, and
the signal processing means retrieves the reference data by using the feature amount as a key and estimates the degree of defect formed in the pipe.

5. The defect analysis device according to claim 4 , wherein
the defect analysis device further includes pipe information acquisition means for acquiring information about the pipe in which defect exists,
the reference data storage means stores the reference data for each of the information about the pipe, and
the signal processing means specifies the reference data to be retrieved by using the information about the pipe acquired by the pipe information acquisition means and retrieves the specified reference data by using the feature amount as the key.

6. The defect analysis device according to claim 1 , wherein
the vibration means applies the vibration to at least one of the fluid flowing in the pipe in which defect is detected and the pipe, and
the first detection means detects the vibration radiated to the outside of the pipe through the defect.

7. The defect analysis device according to claim 1 , wherein
the vibration means is installed on the outer surface of the pipe or the outer surface of a branch pipe connected to the pipe.

8. The defect analysis device according to claim 1 , wherein
the pipe is installed under the ground, and
the first detection means is installed on the surface of the ground and detects the vibration that is radiated to the outside of the pipe and reaches the surface of the ground.

9. The defect analysis device according to claim 8 , wherein
the first detection means is configured to be moved to a plurality of different locations on the surface of the ground and to detect the vibration at each of a plurality of the installation locations, and
the signal processing means uses a plurality of vibration waveforms acquired at each of a plurality of the installation locations by the first detection means and specifies the location of the defect formed in the pipe.

10. The defect analysis device according to claim 1 , wherein
the defect analysis device further includes second detection means for detecting at least one of the vibration propagating through the pipe and the vibration propagating through the fluid flowing in the pipe, and
the signal processing means detects the formation of defect in the pipe by using the vibration detected by the second detection means.

11. The defect analysis device according to claim 10 , wherein
the second detection means is installed on the outer surface of the pipe or the outer surface of the branch pipe connected to the pipe.

12. The defect analysis device according to claim 10 , wherein
the defect analysis device includes a plurality of the second detection means and the plurality of the second detection means are installed at a predetermined interval, and
the signal processing means specifies a coarse indication of the location of the defect formed in the pipe by using the vibration detected by the plurality of the second detection means.

13. The defect analysis device according to claim 10 , wherein
when the signal processing means detects the formation of defect in the pipe, the vibration means applies the vibration and the first detection means detects the vibration applied by the vibration means.

14. A defect analysis method in which a computer processor executes the steps of:
applying vibration with a plurality of frequency components to at least one of fluid flowing in a pipe and the pipe,
detecting the applied vibration with the plurality of frequency components,
extracting a feature amount from a vibration waveform acquired in detecting the applied vibration, and
estimating a degree of defect formed in the pipe by using the extracted feature amount.

15. The defect analysis method according to claim 14 , wherein
in extracting the feature amount, at least one of a peak frequency and a sharpness of a peak is extracted as the feature amount.

16. The defect analysis method according to claim 14 , wherein the computer processor further executes the steps of:
detecting at least one of the vibration propagating through the pipe and the vibration propagating through the fluid flowing in the pipe, and
detecting the formation of defect in the pipe by using the detected vibration.

17. The defect analysis method according to claim 16 , wherein
when the formation of defect in the pipe is detected, application of vibration is started and the applied vibration is detected.

18. A non-transitory computer-readable medium, storing a program which when executed by a computer causes the computer to perform a method comprising:
applying vibration with a plurality of frequency components to at least one of fluid flowing in a pipe and the pipe,
detecting the vibration applied by the vibration means,
extracting a feature amount from a vibration waveform acquired by the computer, and
estimating a degree of defect formed in the pipe by using the extracted feature amount.

19. The non-transitory computer-readable storage medium, storing the program according to claim 18 , which when executed by the computer, further causes the computer to perform the steps of:
detecting at least one of the vibration propagating through the pipe and the vibration propagating through the fluid flowing in the pipe, and
detecting the formation of defect in the pipe by using the detected vibration.

20. The non-transitory computer-readable medium, storing the program according to claim 19 , which when executed by the computer, further causes the computer to perform the steps of:
applying the vibration, and
detecting the applied vibration after detecting the formation of the defect in the pipe.

Assignees

• Nec Corp

Inventors

• Takahashi Masatake
• Tomiyama Mizuho
• Sasaki Yasuhiro

Classifications

• G01N29/341

  with time characteristics · CPC title

• G01M3/243 Primary

  for pipes · CPC title

• F17D5/06

  using electric or acoustic means · CPC title

• G01M3/00

  Investigating fluid-tightness of structures · CPC title

• G01M5/0025 Primary

  of elongated objects, e.g. pipes, masts, towers or railways (G01M5/0058 takes precedence) · CPC title