Leak detection device, leak detection method and program

Patent metadata

Field	Value
Publication number	US-2015253215-A1
Application number	US-201314431803-A
Country	US
Kind code	A1
Filing date	Sep 27, 2013
Priority date	Sep 28, 2012
Publication date	Sep 10, 2015
Grant date	—

Abstract

A leak detection device is provided which comprises: in order to suppress effects of extraneous vibration and improve accuracy of leak detection, a first detection unit ( 6 ) which detects vibration in a first direction and output a first signal S 1 representing a magnitude of the vibration in the first direction, the first detection unit ( 6 ) being installed to a pipe ( 2 ) in which fluid ( 5 ) flows; a second detection unit ( 7 ) which detects vibration in a second direction different from the first direction and output a second signal S 2 representing a magnitude of the vibration in the second direction, the second detection unit ( 7 ) being installed to the pipe ( 2 ); and a signal processing unit ( 10 ) which performs an arithmetic operation processing using the first signal S 1 and the second signal S 2.

First claim

1 . A leak detection device comprising: a first detection unit that detects vibration in a first direction and outputs a first signal S 1 that represents a magnitude of the vibration in the first direction, the first detection unit that is installed to a pipe in which fluid flows; a second detection unit that detects vibration in a second direction different from the first direction and outputs a second signal S 2 that represents a magnitude of the vibration in the second direction, the second detection unit that is installed to the pipe; and a signal processing unit that performs an arithmetic operation processing using the first signal S 1 and the second signal S 2 .

2 . The leak detection device according to claim 1 , wherein the first direction is a longitudinal direction of the pipe and the second direction is a direction perpendicular to the first direction.

3 . The leak detection device according to claim 1 or 2 , wherein, using a third signal F 1 that represents each frequency of a magnitude of vibration in the first direction calculated using the first signal S 1 and a fourth signal F 2 representing each frequency of a magnitude of vibration in the second direction calculated using the second signal S 2 , the signal processing unit generates, according to LS=F 1 −F 2 , a signal LS that represents each frequency of a difference obtained by subtracting each frequency of the magnitude of the vibration in the second direction in the fourth signal F 2 from the magnitude of the vibration in the first direction in the third signal F 1 and performs, using the signal LS, at least one of processing, a process of determining a presence or absence of a leak of fluid from the pipe and a process of identifying a leak position.

4 . The leak detection device according to claim 1 , wherein, using K 1 ×F 1 which is a signal obtained by correcting a magnitude of vibration in the first direction in a third signal F 1 using the third signal F 1 that represents each frequency of the magnitude of the vibration in the first direction calculated using the first signal S 1 and a first amplification factor K 1 which is a predetermined constant and K 2 ×F 2 which is a signal obtained by correcting a magnitude of vibration in the second direction in a fourth signal F 2 using the fourth signal F 2 that represents each frequency of the magnitude of the vibration in the second direction calculated using the second signal S 2 and a second amplification factor K 2 which is a predetermined constant, the signal processing unit generates, according to LS=K 1 ×F 1 −K 2 ×F 2 , a signal LS that represents each frequency of a difference obtained by subtracting each frequency of a magnitude of vibration of K 2 ×F 2 from a magnitude of vibration of K 1 ×F 1 and performs, using the signal LS, at least one of processing, a process of determining a presence or absence of a leak of fluid from the pipe and a process of identifying a leak position.

5 . The leak detection device according to claim 1 , wherein, using C 1 ×F 1 which is a signal obtained by correcting each frequency of a magnitude of vibration in the first direction in the third signal F 1 using the third signal F 1 that represents each frequency of the magnitude of the vibration in the first direction calculated using the first signal S 1 and a first amplification factor C 1 which is a variable to be determined by each frequency and C 2 ×F 2 which is a signal obtained by correcting each frequency of a magnitude of vibration in the second direction in the fourth signal F 2 using the fourth signal F 2 that represents each frequency of the magnitude of the vibration in the second direction calculated using the second signal S 2 and a second amplification factor C 2 which is a variable to be determined by each frequency, the signal processing unit generates, according to LS=C 1 ×F 1 −C 2 ×F 2 , a signal LS that represents each frequency of a difference obtained by subtracting each frequency of a magnitude of vibration of C 2 ×F 2 from a magnitude of vibration of C 1 ×F 1 and performs at least one of processing, a process of determining a presence or absence of a leak of fluid from the pipe and a process of identifying a leak position using the signal LS.

6 . The leak detection device according to claim 1 , wherein the first and second detection units are installed to the pipe directly or via a mechanism through which vibration propagates.

7 . The leak detection device according to claim 6 , wherein a plurality of the first detection units are installed to the pipe along a longitudinal direction thereof, the second detection unit is installed between a first first detection unit and a second first detection unit among the plurality of the first detection units, and the signal processing unit performs an arithmetic operation processing using the first signal S 1 output by the first first detection unit and the second signal S 2 output by the second detection unit and also performs an arithmetic operation processing using a first signal S 1 output by the second first detection unit and the second signal S 2 .

8 . The leak detection device according to claim 1 , the leak detection device comprising a sensor that detects vibration in at least two axial directions, wherein the first detection unit and the second detection unit are configured of the sensor.

9 . A leak detection method comprising: detecting vibration in a first direction by controlling a sensor installed to a pipe in which fluid flows and outputting a first signal S 1 representing a magnitude of the vibration in the first direction; detecting vibration in a second direction different from the first direction by controlling a sensor installed to the pipe and outputting a second signal S 2 representing a magnitude of the vibration in the second direction; and a signal processing step of performing an arithmetic operation processing using the first signal S 1 and the second signal S 2 .

10 . A program for causing a computer to function as: a first detection means for detecting vibration in a first direction by controlling a sensor installed to a pipe in which fluid flows and outputting a first signal S 1 representing a magnitude of the vibration in the first direction; a second detection means for detecting vibration in a second direction different from the first direction by controlling a sensor installed to the pipe and outputting a second signal S 2 representing a magnitude of the vibration in the second direction; and a signal processing means of performing an arithmetic operation processing using the first signal S 1 and the second signal S 2 .

Assignees

• Nec Corp

Inventors

• Tomiyama Mizuho
• Takahashi Masatake

Classifications

• G01M3/243 Primary

  for pipes · CPC title

• F17D5/06

  using electric or acoustic means · CPC title

• G01M3/16 Primary

  using electric detection means ({G01M3/045,} G01M3/06, G01M3/12, G01M3/20, G01M3/24, G01M3/26 take precedence) · CPC title

• G01M3/24

  using infrasonic, sonic or ultrasonic vibrations · CPC title