KR20180130771A - System for monitoring wall-thinning of pipe and method thereof - Google Patents

Abstract

Provided are a system for monitoring a wall-thinning state of a pipe and a method thereof. The system for monitoring a wall-thinning state of a pipe according to an embodiment of the present invention comprises: a sensor portion arranged in a fluid flowing pipe by a first distance away from a location applied with an impact, and detecting a pressure wave within the pipe constituted by the impact; a display portion displaying a distribution characteristic of the pressure wave; and a control portion providing a reference bent degree in accordance with a pre-measured wall-thinning state of the pipe so as to convert the time to the frequency with respect to the detected pressure wave, control to calculate a conversion graph to display the conversion graph in the display portion, and determine a wall-thinning state of a pipe constituted by a bent degree of a specific line of the calculated conversion graph.

Description

TECHNICAL FIELD [0001] The present invention relates to a piping system for monitoring piping,

More particularly, the present invention relates to a monitoring system and method for monitoring the state of the piping of a piping system capable of monitoring the durability of the piping to a specific position with only one sensor.

In the case of a plant including a power plant, there have been reported cases of wall thinning and breakage of piping due to deterioration of piping installed at the time of initial construction. Especially, since pipe thinning and breakage accidents occurred at Mihama nuclear power plant in Japan, there is an increasing interest in techniques for understanding the decline of piping.

In the case of power plants, ultrasonic thickness measurement techniques are widely applied in the field in order to grasp the durability of piping. This method can accurately measure the pipe thickness, but it takes a lot of time because it measures a number of measurement points distributed on the pipe surface. For this reason, it is difficult to inspect the piping within the preventive maintenance period (about 30 days) at the power plant where there are thousands of inspection target pipes.

In recent years, a method of measuring the propagation velocity of a vibration wave has been studied in order to use a phenomenon in which a propagation velocity of a vibration wave propagating in a pipe is changed when a pipe is thinned, Two sensors should be used. In order to accurately measure the propagation speed, hardware having a high sampling frequency (time domain resolution) should be provided.

Furthermore, since two sensors are used, time synchronization between two sensors is required to measure the arrival time delay (or propagation speed) of a vibration wave arriving at exactly two sensors.

JP 4012237 B (September 14, 2007 Enrollment)

According to an aspect of the present invention, there is provided a system for monitoring a deceleration state of a piping, which can monitor and diagnose an overall declining state in a longitudinal direction of a pipe to a specific position using one sensor, And methods.

According to a first aspect of the present invention, there is provided a method of detecting a pressure wave in a pipeline through which a fluid flows, the method comprising: sensing a pressure wave in the pipe by a first distance from an impacted position; A display unit for displaying a dispersion characteristic of the pressure wave; And a control unit configured to perform time-frequency conversion on the sensed pressure wave to control the display unit to display a conversion graph and to display the conversion graph on the display unit, and to measure the degree of bending of the characteristic line of the conversion graph, And a controller for providing a reference bending degree according to a deceleration state of the pipe.

According to a second aspect of the present invention, there is provided a pressure sensor comprising: a sensor part disposed at a first distance from a position where an impact is excited in a pipe through which a fluid flows, and sensing a pressure wave in the pipe due to the impact; A display unit for displaying a dispersion characteristic of the pressure wave; And an ambiguity conversion unit configured to perform ambiguity conversion on the sensed pressure wave to control the display unit to display a conversion graph and to display the conversion graph on the display unit so that the slope of the characteristic line of the conversion graph is calculated, And a control unit for providing a reference slope according to the deceleration state of the pipe.

According to a third aspect of the present invention, there is provided a method comprising: impacting a pipe through which a fluid flows; Sensing a pressure wave in the pipe by the impact by a sensor portion spaced a first distance from an excited location; Performing time-frequency conversion on the sensed pressure wave; Calculating a conversion graph according to the conversion result and displaying the conversion graph on a display unit; And providing a reference bending degree according to a reduction state of the pipe measured in advance so as to determine a deceleration state of the pipe by a degree of bending of a characteristic line of the calculated conversion graph, do.

According to a fourth aspect of the present invention, there is provided a process for producing a fluid, comprising: impacting a pipe through which a fluid flows; Sensing a pressure wave in the pipe by the impact by a sensor portion spaced a first distance from an excited location; Performing ambiguity conversion on the sensed pressure wave; Calculating a conversion graph according to the conversion result and displaying the conversion graph on a display unit; And providing a reference slope according to a reduction state of the pipe measured in advance so as to determine a declining state of the pipe by a slope of a characteristic line of the calculated conversion graph.

The monitoring system and method of monitoring the piping according to an embodiment of the present invention can reduce the number of sensors required for a large number of pipeline inspection by monitoring the aging or decaying state of the piping at a specific location by using one sensor, Can be saved.

Further, the present invention provides a result of pre-simulation according to the fatigue state of the piping so that the decaying state of the piping can be easily grasped by using the dispersion characteristic of the pressure wave, so that the aging state of the plant piping system can be detected early, Can be prevented in advance and the stability can be improved.

Further, the plurality of sensors of the present invention may be installed for each position of interest, and the state of the pipe may be monitored for each position, thereby shortening the time required for inspecting a large number of pipes to be inspected.

In addition, since a plurality of sensors are installed at a plurality of positions and the result of sensing by wireless communication is transmitted, the system maintenance and maintenance of the plant piping system can be systematically managed, thereby reducing the maintenance cost.

FIG. 1 is a schematic view showing a state in which a pipe decoupling monitoring system according to an embodiment of the present invention is installed,
FIG. 2 is a block diagram of a system for monitoring the declining state of piping according to an embodiment of the present invention,
3 is a graph showing a change in the propagation velocity according to the pipe thickness,
FIG. 4 is a graph showing response characteristics of a pressure wave in the time-frequency domain in a decelerating state monitoring system of a pipe according to an embodiment of the present invention,
5 is a graph showing a response characteristic of an ambience portion of a pressure wave in a declining state monitoring system of a pipe according to an embodiment of the present invention,
6 is a flowchart of an example of a method for monitoring the declining state of a pipe according to the embodiment of the present invention,
FIG. 7 is a flowchart of another example of a declining state monitoring system for pipes according to an embodiment of the present invention. FIG.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains. The present invention may be embodied in many different forms and is not limited to the embodiments described herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a system for monitoring the declining state of piping according to an embodiment of the present invention will be described in detail with reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view showing a state in which a pipe decoupling monitoring system according to an embodiment of the present invention is installed. FIG.

1 is a perspective view of a piping depression monitoring system according to an embodiment of the present invention. As shown in FIG. That is, the declining state monitoring system 100 of the pipe includes one sensor unit 110 at a position (x _s ) spaced a certain distance from an arbitrary position xe excited by the impact in the pipe 10, And to monitor the pipe fatigue state using the dispersive characteristic of the pressure wave caused by the fluid flowing in the pipe 10 due to the impact.

That is, the durability monitoring system 100 of the piping includes a sensor unit 110 capable of sensing the pressure wave due to the fluid flowing in the piping 10, periodically measuring the pressure wave by the exciter The signal is converted so that the dispersion characteristic can be displayed well and the overall decaying state of the inside of the pipe 10 is grasped by comparing it with the measured value (initial value) in the initial state of the pipe 10 in which the thinning has not proceeded.

When the thickness threshold (h _th ) of the pipeline 10 to be managed is set, the declining state monitoring system 100 of the piping can perform the simulation for the corresponding thickness threshold value h _th The conversion graph is calculated and the attribute of the characteristic line of the conversion graph is calculated to compare with the preset reference value or the threshold to monitor and manage the declining state of the pipe 10. [

Thus, the declining state monitoring system 100 of the piping can measure the propagation velocity of the vibration wave in the longitudinal direction of the piping 10 by using the two or more sensors with impact on the piping 10, 10, it is possible to monitor and diagnose the overall declining state in the longitudinal direction of the pipe 10 at a low cost by using one sensor, compared to the conventional method of detecting the declining state of the pipe 10.

At this time, the fluid flowing through the pipe 10 may be a liquid such as cooling water or crude oil. That is, the declining state monitoring system 100 of the pipe according to the embodiment of the present invention can be applied to a cooling water pipe, a sewage water supply pipe, a water supply pipe or a crude oil supply pipe of a power plant.

Further, the fluid flowing through the pipe 10 may be a gas such as a gas or the like. That is, the system for monitoring the declining state of piping according to the embodiment of the present invention can be applied to gas piping. At this time, the declining state monitoring system 100 of the pipe performs additional signal processing before converting the sensed pressure wave because the density of the fluid is smaller than that of the liquid and the pressure wave sensed by the sensor is fine .

1, there is a propagating mode that propagates in the longitudinal direction of the pipe 10 when the fluid flows into the piping system, and this mode is a mode of propagating along the surface of the pipe 10 surrounding the fluid The vibrating wave and the fluid contained in the pipe 10 and the surface of the pipe 10 can be divided into a pressure wave that is coupled and propagated together.

At this time, the propagation velocity of the pressure wave generated in the pipe 10 can be expressed theoretically as shown in Equation (1).

Here, C _f is the sound velocity, B _f is a bulk modulus of the fluid, r is the radius of the pipe, h is the thickness of the pipe (h), E is Young's modulus (Young's modulus), ρ is the density of the pipes of the pipe material of the fluid, ω is the angular frequency (ω = 2πf).

As can be seen from Equation (1), it can be seen that the propagation velocity c of the pressure wave also changes with the thickness h of the pipe, the Young's modulus E of the material, and the frequency omega.

3 is a graph showing a change in the propagation velocity according to the pipe thickness h. 3, the diameter of the pipe 10 is 150 mm.

Since this pressure wave propagates in the longitudinal direction of the pipe 10 and the propagation velocity c changes in accordance with the thickness h of the pipe as shown in Fig. 3, when the propagation velocity c of the pressure wave is measured The degree of thinning of the pipe 10 can be grasped.

However, in order to measure the propagation velocity of the pressure wave in the pipe 10, usually two or more sensors are required. In addition, in order to accurately measure the propagation velocity, the time delay of the pressure waves reaching the two sensors must be accurately measured , And high sampling frequency (time resolution).

Furthermore, in order to measure the time delay between two sensors, time synchronization between the two sensors must be performed.

In particular, when wireless sensors other than the wired method are used, it takes a lot of time to realize synchronization, and since low-cost wireless sensors do not support most of them, expensive wireless sensors are required.

In addition, since the increase in the number of sensors in the actual plant site leads to an increase in the installation / maintenance cost, the above-mentioned matters must be considered in order to improve the applicability in the actual plant site.

1, the assumption is that with the pressure wave (p _e) by having at any point (x _e) on the pipe, the length of the pressure wave pipe 10 with at the point (x _e) And the pressure wave p _e measured at the sensor unit 110 at a position (x _s ) spaced a certain distance therefrom can be expressed by the following equation (2).

Where p _e is the magnitude of the pressure wave due to the excitation, k is the wave number of the pressure wave, ω is the angular frequency (ω = 2πf), and c is the propagation velocity of the pressure wave.

At this time, the propagation speed c in Equation (2) is expressed by Equation (1) and has a different value depending on the frequency (?). That is, it can be seen that the pressure wave has a dispersion characteristic in which the low frequency component and the high frequency component propagate at different propagation velocities.

That is, since the fluid flows after the pipe 10 is installed, the pipe 10 is caused to have a thinning phenomenon due to friction with the pipe 10 or the like, so that the thickness of the pipe 10 gradually decreases with time . As described above, when the thickness of the pipe 10 is reduced, the flow characteristics of the fluid in the pipe 10 change, so that the dispersion characteristics of the pressure wave due to the fluid inside the pipe 10 change.

Therefore, the declining state monitoring system 100 of the pipe according to the embodiment of the present invention monitors the declining state of the pipe 10 by one sensor using the dispersion characteristic of the pressure wave propagating along the inside of the pipe 10 This paper proposes a solution. At this time, the present invention utilizes a transformation that can easily grasp the dispersion characteristic of the pressure wave.

In one example, such a dispersion characteristic can be analyzed by time-frequency analysis of the vibration response measured at one sensor unit 110. [

At this time, the time-frequency analysis of the pressure wave as shown in equation (2) can be expressed by the following equation (3).

Where * is a complex conjugate, f is the frequency, and τ is the time delay.

FIG. 4 is a graph showing response characteristics of a pressure wave in a time-frequency domain in a deceleration monitoring system of a pipe according to an embodiment of the present invention. FIG.

4 shows a simulation result of a vibration response of a pressure wave calculated at a position (x _s ) at a distance of 10 m from a point (x _e ) of a pipe 10 having a diameter of 150 mm.

 4, as shown in the second graph, as the thickness h of the pipe 10 decreases, the arrival delay time of the pressure wave increases as shown in the second graph, It can be observed that the dispersive characteristic changes as shown in Fig.

3, the propagation velocity c of the pressure wave tends to decrease as the thickness h of the pipe 10 decreases, and the dispersion characteristic gradually increases in the high frequency component of the pressure wave Can be observed.

In particular, as shown in the bottom-most graph in Fig. 4, the characteristic line (yellow) of the conversion graph representing the time-frequency response of the pressure wave indicates that a larger change in the high frequency component as the thickness h of the pipe 10 decreases . ≪ / RTI > As described above, the declining state of the pipe 10 can be grasped according to the degree of bending of the characteristic line in the time-frequency conversion graph of the pressure wave.

Meanwhile, the variation of the dispersion characteristic according to the variation of the thickness h of the pipe 10 can be more clearly seen in the ambiguity domain.

At this time, the ambiguity conversion for the pressure wave as shown in Equation (2) can be expressed by the following Equation (4).

Where * is a complex conjugate, t is time, t is time delay, and v is a frequency variation.

5 is a graph showing the response characteristics of the ambience portion of the pressure wave in the declining state monitoring system of the piping according to the embodiment of the present invention.

5 shows a simulation result of a vibration response of a pressure wave calculated at a position (x _s ) at a distance of 10 m from a point (x _e ) of a pipe 10 having a diameter of 150 mm.

As shown in the lower graph of FIG. 5, the pressure wave signal having the dispersion characteristic is expressed in the form of a characteristic line (yellow) passing through the origin in the ambiguity domain, and therefore, It is possible to effectively express the change in delay tau.

That is, as the thickness h of the piping 10 decreases, the inclination changes about the origin of the characteristic line in the ambience portion of the pressure wave. Particularly, as the thickness h of the piping 10 decreases, It can be observed that the change of the slope about the origin is large. Thus, in the ambiguity conversion graph of the pressure wave, the declining state of the pipe 10 can be grasped according to the slope with respect to the origin of the characteristic line.

As described above, the dispersion characteristic of the pressure wave in the pipe 10 can be easily grasped from the conversion graph by time-frequency conversion or ambiguity conversion.

The piping declining state monitoring system 100 using the dispersion characteristics of pressure waves is shown in Fig. FIG. 2 is a block diagram of a system for monitoring the declining state of piping according to an embodiment of the present invention.

The monitoring system 100 for monitoring the state of the pipe according to an embodiment of the present invention includes a sensor unit 110, a control unit 120, a storage unit 130, and a display unit 140.

The sensor unit 110 is disposed at a first distance from the position (x _e ) where the impact is excited in the pipe 10. The sensor unit 110 detects a pressure wave in the pipe 10 due to an impact applied to the pipe 10.

For example, the sensor unit 110 may be a vibration sensor such as an accelerometer or a pressure sensor such as a hydrophone capable of directly measuring a pressure wave inside the pipe 10.

The control unit 120 time-frequency converts the pressure wave detected by the sensor unit 110 as shown in Equation (3) to obtain the dispersion characteristic.

Also, the control unit 120 controls the display unit 140 to display the time-frequency conversion graph as shown in FIG.

At this time, the control unit 120 provides the degree of reference warpage according to the fatigue state of the pipe measured in advance so as to determine the decline condition of the pipe 10 by the degree of warp of the characteristic line of the calculated conversion graph.

That is, the control unit 120 displays the conversion graph on the display unit 140 so that the user can determine the deceleration state of the pipe 10 based on the conversion graph and the reference information, As shown in FIG.

Thus, since the aging state of the plant piping system can be detected early, the plant accident can be prevented in advance and the stability can be improved.

Alternatively, the control unit 120 may calculate the degree of bending of the characteristic line from the conversion graph, and compare the degree of bending of the characteristic line with the degree of standard bending stored in the storage unit 130 to calculate the thickness h of the pipe 10. At this time, the control unit 120 may calculate the thickness h of the pipe 10 by extracting the characteristic line from the converted graph by image processing, and then calculating the degree of bending of the characteristic line and comparing the degree of bending with the reference bending degree.

Thereby, the declining state monitoring system 100 of the piping can automatically determine the deceleration state of the piping 10 without determining it by the user.

The storage unit 130 may store the reference bending degree of the time-frequency conversion graph measured in advance according to the thickness h of the pipe 10. That is, by measuring the pressure wave for each thickness h of the piping 10 by pre-simulation or experiment, time-frequency conversion is performed to calculate the conversion graph, and the degree of bending of the characteristic line is calculated from the calculated conversion graph. h) can be stored as a standard degree of warpage.

The display unit 140 displays the dispersion characteristic of the pressure wave calculated by the control unit 120 so that the user can determine the deceleration state of the pipe 10 by the conversion graph.

As another example, the control unit 120 performs ambiguity conversion on the pressure wave sensed by the sensor unit 110 as shown in Equation (4) in order to grasp the dispersion characteristic to calculate a conversion graph.

In addition, the control unit 120 controls the display unit 140 to display the ambiguity conversion graph as shown in FIG.

At this time, the control unit 120 provides a reference slope according to the fatigue state of the pipe measured in advance so as to determine the declining state of the pipe 10 by the slope of the characteristic line of the calculated conversion graph.

That is, the control unit 120 displays a conversion graph on the display unit 140 so that the user can determine the deceleration state of the pipe 10 based on the conversion graph and the reference information, and simultaneously displays the conversion graph on the thickness h of the pipe 10 So as to provide the reference information according to the reference information.

Alternatively, the control unit 120 may calculate the slope of the characteristic line from the conversion graph, and compare the slope of the characteristic line with the reference slope stored in the storage unit 130 to calculate the thickness h of the pipe 10. At this time, the control unit 120 can calculate the thickness h of the pipe 10 by extracting the characteristic line from the converted graph by image processing, and then calculating the slope of the characteristic line and comparing it with the reference slope.

Thereby, the declining state monitoring system 100 of the piping can automatically determine the deceleration state of the piping 10 without determining it by the user.

At this time, the storage unit 130 may store the reference slope of the previously measured ambiguity change graph according to the thickness of the pipe 10. That is, by measuring the pressure wave for each thickness h of the piping 10 by preliminary simulation or experiment, the pressure hysteresis is converted into an ambulance, and a slope of the characteristic line is calculated from the calculated conversion graph, Can be stored as a standard reference slope.

Meanwhile, the declining state monitoring system 100 of the pipe according to the embodiment of the present invention can measure the surface vibration wave in addition to the pressure wave with one sensor unit 110.

To this end, the sensor unit 110 may be disposed at a second distance smaller than the first distance to sense the surface vibration wave of the pipe 10 further.

Since the surface vibration wave has a fast decaying characteristic, the pressure wave and the surface vibration wave can be simultaneously measured from one sensor unit 110 by disposing the sensor unit 110 at a shorter distance from the excitation position (xe).

At this time, the control unit 120 filters the surface vibration wave to separate the pressure wave and the surface vibration wave simultaneously measured by the sensor unit 110, and performs time-frequency conversion or ambiguous conversion of each of the pressure wave and the surface vibration wave .

Also, the declining state monitoring system 100 of the pipe according to the embodiment of the present invention can collectively monitor the declining state of the pipe 10 at a plurality of positions.

For this, a plurality of sensor units 110 may be provided at a plurality of predetermined positions of the pipe 10. Here, the sensor unit 110 may transmit the detection result to the control unit 120 through the wireless communication, but the present invention is not limited thereto, and the sensor unit 110 may transmit the sensing result through the wired communication.

At this time, the control unit 120 may control to display the deceleration state of the pipe 10 according to the positions corresponding to the plurality of sensor units 110. For example, the control unit 120 may divide the screen into a predetermined number of screens on the display unit 140, and control the display unit 140 to simultaneously display the conversion results for a plurality of positions.

Thus, by providing a plurality of sensors in advance in the target pipe 10 and collectively processing the deceleration state of the pipe 10 through the control unit 120 at one place like the control station, Periodic measurement and monitoring of the land surface can be carried out by unattended monitoring, thereby shortening the time required for inspecting a large number of pipes to be inspected.

Furthermore, by using a low-cost wireless sensor, it is possible to easily establish and change unattended monitoring, and it is possible to systematically manage aging and maintenance of the plant piping system, thereby reducing maintenance costs.

Also, the declining state monitoring system 100 of the pipe may further include an impact generator (not shown) having an impact on the pipe 10 at a position spaced a predetermined distance from the plurality of sensor units 110. Here, the impact generator may include a plurality of sensor units 110 at a distance at which a pressure wave can be detected.

Also, the declining state monitoring system 100 of the pipe according to the embodiment of the present invention can generate an alert for the deceleration state of the pipe 10 set in advance.

For this, the controller 120 sets the thickness h and the thickness threshold h _th of the pipe 10 calculated as described above, when the thickness threshold h _th of the pipe 10 is preset by the user It is possible to generate an alarm for the declining state of the pipe 10 by comparing.

That is, when the thickness h of the calculated pipe 10 reaches the thickness threshold h _th , the controller 120 generates an alarm to replace or repair the pipe 10, or notifies the predetermined terminal . Here, the terminal may be a computer, a mobile phone, a smart phone, and a portable device capable of communicating.

Thus, it is possible to more efficiently perform the monitoring of the declining state by automatically determining the timing of replacing or maintenance of piping as well as monitoring the declining state of the piping 10, thereby reducing the maintenance cost by reducing the input of related personnel can do.

Hereinafter, the method of monitoring the declining state of the piping of the present invention will be described with reference to Figs. 6 and 7. Fig.

Fig. 6 is a flowchart of an example of a method for monitoring the reduction state of piping according to the embodiment of the present invention.

The method of monitoring the declining state of a pipe according to an embodiment of the present invention includes a step S201 of applying impact, a step S202 of sensing a pressure wave, a step of performing time-frequency conversion S203, And displaying S204 and determining the declining state of the pipe (S205 and S206).

6, at a position (x _e ) spaced from the position (x _s ) where the sensor unit 110 is installed in the pipe 10 through which the fluid flows, the pipe 10 (Step S201).

Next, a pressure wave generated in the pipe 10 is sensed by the sensor unit 110 (step S202). Here, the sensor unit 110 may be a vibration sensor such as an accelerometer, or may be a pressure sensor such as a hydrophone capable of directly measuring a pressure wave inside the pipe 10.

Next, in order to grasp the dispersion characteristic with respect to the pressure wave sensed by the sensor unit 110, time-frequency conversion is performed as shown in Equation (3) (Step S203).

Next, a conversion graph according to the result of the time-frequency conversion is calculated and displayed on the display unit 140 as shown in FIG. 4 (step S204).

Next, by providing the degree of reference warpage according to the depressed state of the pipe 10 measured in advance so as to determine the declining state of the pipe 10 by the degree of warp of the feature line of the displayed conversion graph, (Step S206).

Alternatively, when the declining state of the piping 10 is automatically determined, the degree of warping of the characteristic line of the conversion graph calculated between step S205 and step S206 is calculated (step S205). Here, after the feature lines are extracted from the converted graph by image processing, the degree of warping of the characteristic lines can be calculated.

At this time, in step S206, the thickness h of the target pipe 10 is calculated by comparing the degree of bending of the feature line of the conversion graph with the pre-calculated degree of bending according to the thickness h of the pipe 10 can do.

On the other hand, when the thickness threshold h _th of the pipe 10 is preset by the user, the determination in step S206 is performed by comparing the calculated thickness h of the pipe 10 with the thickness threshold h _th , 10) can be generated.

That is, when the thickness h of the pipe 10 calculated as described above reaches the thickness threshold h _th , it is possible to generate an alarm about the deceleration condition to replace or repair the pipe 10, It is possible to notify the terminal. Here, the terminal may be a computer, a mobile phone, a smart phone, and a portable device capable of communicating.

FIG. 7 is a flowchart of another example of a declining state monitoring system for pipes according to an embodiment of the present invention. FIG.

The method for monitoring the durability of piping according to an embodiment of the present invention includes steps S301, S302, S303, A step of displaying S304, and a step of determining the declining state of the pipe (S305 and S306).

7, at a position (x _e ) spaced from the position (x _s ) where the sensor unit 110 is installed in the pipe 10 through which the fluid flows, the pipe 10 (Step S301), and senses a pressure wave generated in the pipe 10 by the impact applied by the sensor unit 110 (step S302).

Next, in order to grasp the dispersion characteristic with respect to the pressure wave sensed by the sensor unit 110, Ambiguity conversion is performed according to Equation (4) (step S303).

Next, the conversion graph according to the result of the ambiguity conversion is calculated and displayed on the display unit 140 as shown in FIG. 5 (step S304).

Next, by providing a reference slope according to the fatigue state of the pipe 10 measured in advance so as to determine the declining state of the pipe 10 by the slope of the characteristic line of the displayed conversion graph, The land surface state is determined (step S306).

Alternatively, when the declining state of the piping 10 is automatically determined, the slope of the characteristic line of the conversion graph calculated between steps S305 and S306 is calculated (step S305). Here, the characteristic line can be extracted from the converted graph by image processing, and the slope of the characteristic line can be calculated.

At this time, in step S306, the thickness h of the target pipe 10 can be calculated by comparing the slope of the characteristic line of the converted graph with the slope calculated in advance according to the thickness h of the pipe 10 have.

On the other hand, when by a user to a preset thickness threshold value (h _th) of the pipe 10, the determination step of step S306 is the pipe compared to the thickness (h) and thickness threshold (h _th) of the output pipe 10 ( 10) can be generated.

Such a method may be implemented by a decoupling monitoring system 100 of a piping as shown in FIG. 1, and in particular may be implemented as a software program that performs these steps, Readable recording medium, or by a computer data signal coupled with a carrier wave in a transmission medium or a communication network.

In this case, the computer-readable recording medium includes all kinds of recording apparatuses in which data that can be read by a computer system is stored. For example, ROM, RAM, CD-ROM, DVD- A floppy disk, a hard disk, an optical data storage device, or the like.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

10: Piping 100: Persistent state monitoring system of piping
110: sensor unit 120:
130: storage unit 140: display unit

Claims (12)

A sensor unit disposed at a first distance from an impacted position of the pipe through which the fluid flows and sensing a pressure wave in the pipe due to the impact;
A display unit for displaying a dispersion characteristic of the pressure wave; And
And a control unit for performing time-frequency conversion on the sensed pressure wave to control the display unit to display a conversion graph and to display the conversion graph on the display unit, A control unit for providing a reference bending degree according to the durability of the piping;
Wherein said piping system comprises: The method according to claim 1,
Further comprising a storage section for storing the reference bending degree of a time-frequency conversion graph corresponding to a thickness of the pipe measured in advance,
Wherein the control unit calculates the degree of bending of the characteristic line and calculates the thickness of the pipe by comparing the degree of bending with the degree of the standard bending. A sensor unit disposed at a first distance from an impacted position of the pipe through which the fluid flows and sensing a pressure wave in the pipe due to the impact;
A display unit for displaying a dispersion characteristic of the pressure wave; And
And a control unit for performing an ambiguity conversion on the sensed pressure wave to control the display unit to display the conversion graph and to display the conversion graph on the display unit, A control unit for providing a reference slope according to a reduction state of the pipe;
Wherein said piping system comprises: The method of claim 3,
Further comprising: a storage unit for storing the reference slope of the ambiguity conversion graph according to a thickness of the pipe measured in advance,
Wherein the control unit calculates the slope of the characteristic line and calculates the thickness of the pipe by comparing with the reference slope. The method according to claim 1 or 3,
Wherein the sensor unit is disposed at a second distance smaller than the first distance to further detect a surface vibration wave of the pipe,
Wherein the controller filters the surface vibration wave from the sensing result of the sensor unit and further performs time-frequency conversion or ambiguous conversion of the surface vibration wave. The method according to claim 1 or 3,
Wherein the plurality of sensor units are provided at a plurality of predetermined positions of the pipe, and the sensing result is transmitted to the control unit through wireless communication. The method according to claim 6,
Wherein the control unit controls the display unit to display the deceleration state of the pipe for each position corresponding to the plurality of sensor units. The method according to claim 6,
Further comprising: an impact generator for impacting the pipe at a position spaced a predetermined distance from the plurality of sensor units. The method according to claim 2 or 4,
The control unit sets a predetermined thickness threshold value of the pipe and compares the determined thickness of the pipe with the threshold value to generate an alarm to replace the pipe when the thickness of the pipe reaches the threshold value, A system for monitoring the durability of piping to be notified. The method according to claim 2 or 4,
Wherein the fluid is a liquid or a gas. Impacting the piping through which the fluid flows;
Sensing a pressure wave in the pipe by the impact by a sensor portion spaced a first distance from an excited location;
Performing time-frequency conversion on the sensed pressure wave;
Calculating a conversion graph according to the conversion result and displaying the conversion graph on a display unit; And
Providing a reference bending degree according to a deceleration state of the pipe measured in advance so as to determine a deceleration state of the pipe by a degree of bending of a characteristic line of the calculated conversion graph;
The method comprising the steps of: Impacting the piping through which the fluid flows;
Sensing a pressure wave in the pipe by the impact by a sensor portion spaced a first distance from an excited location;
Performing ambiguity conversion on the sensed pressure wave;
Calculating a conversion graph according to the conversion result and displaying the conversion graph on a display unit; And
Providing a reference slope according to a reduction state of the pipe measured in advance so as to determine a declining state of the pipe by a slope of a characteristic line of the calculated conversion graph;
The method comprising the steps of:

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