KR20200125362A - Device and method for nondestructive inspection using acoustic signature - Google Patents

Abstract

The present invention relates to a nondestructive inspection apparatus using an acoustic signal and an inspection method thereof and, more specifically, to a nondestructive inspection apparatus using an acoustic signal to create a heat map of an inspection target by using the attenuation characteristic of the acoustic signal and detect an abnormal position by using the created heat map, and an inspection method thereof. According to the present invention, the nondestructive inspection apparatus using an acoustic signal includes the following steps of: setting information about signal attenuation based on each of a plurality of acoustic sensors installed on an inspection target; setting information about a base amplitude with respect to each position where the acoustic sensors are installed; enabling the acoustic sensors to sense an operation sound generated during the operation of the inspection target; and outputting a heat map about the inspection target created based on the operation sound, the information about the base amplitude and the information about the signal attenuation.

Description

Non-destructive inspection device and inspection method using acoustic signals {DEVICE AND METHOD FOR NONDESTRUCTIVE INSPECTION USING ACOUSTIC SIGNATURE}

The present invention relates to a non-destructive inspection apparatus and inspection method using an acoustic signal.

In more detail, it relates to a non-destructive inspection apparatus and inspection method using an acoustic signal for creating a heat map of an inspection target using the attenuation characteristic of an acoustic signal, and detecting an abnormal location using the created heat map.

Various non-destructive inspection methods are applied as a method for inspecting defects in various products such as mechanical parts.

Among them, the inspection method using acoustic inspection is widely used because it can quickly and simply test the defect of the object to be inspected.

As a prior art for a non-destructive test using an acoustic signal, Korean Patent Publication No. 10-0883446 [Document 1] discloses a technical configuration for detecting an abnormal location using a local expression method or an arrival time difference method.

However, the technique according to Document 1 has a problem that the calculation process is complicated and the result value is not precise.

As another prior art for non-destructive testing using acoustic signals, Korean Patent Publication No. 10-1847638 [Document 2] calculates the spectral density using the hit generated by the hit on the test object, and calculates the calculated spectral density. A technical configuration that analyzes the abnormality of the inspection object is posted.

The technique according to this document 2 requires a striking machine to strike an inspection object, so its structure is complicated and there is a problem in that there is a space limitation.

As another prior art for non-destructive testing using acoustic signals, in Korean Patent Publication No. 10-1546889 [Document 3], a plurality of sensors calculates the spectrum of the operating noise generated inside the boiler, and the spectrum for the plurality of sensors A technical configuration that calculates the location of the leak using the triangular diagram of is posted.

In the technique according to this document 3, there is a problem in that it is difficult to accurately calculate the leakage location.

[Document 1] Korean Patent Publication No. 10-0883446 [Document 2] Korean Patent Publication No. 10-1847638 [Document 3] Korean Patent Publication No. 10-1546889

An object of the present invention is to provide a non-destructive inspection apparatus and inspection method using an acoustic signal capable of detecting an abnormal position of an inspection object by using the attenuation characteristic of the signal.

The method of non-destructive testing using an acoustic signal according to the present invention comprises the steps of setting information on signal attenuation based on a plurality of acoustic sensors installed in an object to be inspected, and information on a base amplitude for each location where the acoustic sensor is installed. The setting step, the sound sensor sensing the operation sound generated during the operation of the test object, and the operation sound, the information on the base amplitude, and for the test object created based on the information on the signal attenuation It may include the step of outputting a heat map.

In addition, the setting of the signal attenuation information includes setting information on a signal attenuation rate according to a distance and/or a direction based on each of the acoustic sensors, and the test based on the information on the signal attenuation rate. It may include setting amplitude weights for a plurality of reference positions on the object.

In addition, the step of setting the information on the signal attenuation rate may include setting a plurality of the reference positions on the test object, and non-operational sounds generated at the reference positions when each of the acoustic sensors is not in operation of the test object. Sensing and information on the direction of the reference position based on the acoustic sensor, information on the distance between the reference position and the acoustic sensor, and information on the amplitude difference of the non-operating sound at the adjacent reference position It may include calculating the signal attenuation rate for the test object based on.

In addition, the acoustic sensor includes a first acoustic sensor, a second acoustic sensor adjacent to the first acoustic sensor in a horizontal direction, and a third acoustic sensor vertically adjacent to the first acoustic sensor, and , A plurality of the reference positions may be set between the first acoustic sensor and the second acoustic sensor, and a plurality of the reference positions may be set between the first acoustic sensor and the third acoustic sensor.

In addition, the method may further include detecting an abnormal location of the inspection object from the heat map.

The non-destructive testing apparatus using an acoustic signal according to the present invention includes a plurality of acoustic sensors installed on an inspection object, an attenuating unit for setting information on signal attenuation based on each of the acoustic sensors, and at each location where the acoustic sensor is installed The test target based on the base amplitude unit for setting information on the base amplitude and the operating sound generated during operation of the test target sensed by the acoustic sensor, information on the base amplitude, and information on the signal attenuation. It may include a heat map unit for creating a heat map for.

In addition, the attenuation unit is based on an attenuation rate unit for setting information on a signal attenuation rate according to a distance and/or direction based on each of the acoustic sensors, and a plurality of reference positions on the test object based on the information on the signal attenuation rate. It may include a weight unit to set the amplitude weight for.

In addition, the attenuation rate unit includes information on the direction of the reference position based on the reference position unit and the acoustic sensor for setting the plurality of reference positions on the test object, information on the distance between the reference position and the acoustic sensor, and And an attenuation rate calculator that calculates the signal attenuation rate for the test object based on information on the amplitude difference of the non-operation sound at the adjacent reference position, wherein the non-operation sound is the It may be an acoustic signal generated at the reference position.

In addition, the acoustic sensor includes a first acoustic sensor, a second acoustic sensor adjacent to the first acoustic sensor in a horizontal direction, and a third acoustic sensor vertically adjacent to the first acoustic sensor, and , A plurality of the reference positions may be set between the first acoustic sensor and the second acoustic sensor, and a plurality of the reference positions may be set between the first acoustic sensor and the third acoustic sensor.

In addition, it may further include a detection unit for detecting the abnormal location of the inspection object from the heat map.

The non-destructive inspection apparatus and inspection method using an acoustic signal according to the present invention has an effect of sufficiently accurately detecting the abnormal position by calculating the abnormal position of the inspection object using the attenuation characteristic of the signal.

The non-destructive inspection apparatus and inspection method using an acoustic signal according to the present invention has an effect that by creating a heat map using the attenuation characteristics of the signal, an abnormal position of the inspection object can be accurately calculated and intuitively recognized.

1 to 3 are views for explaining a non-destructive inspection apparatus using an acoustic signal according to the present invention.
4 to 13 are views for explaining a non-destructive inspection method using an acoustic signal according to the present invention.

Hereinafter, a non-destructive inspection apparatus and inspection method using an acoustic signal according to the present invention will be described in detail with reference to the accompanying drawings.

In the present invention, various modifications may be made and various embodiments may be provided, and specific embodiments will be illustrated in the drawings and described in detail in the detailed description. This is not intended to limit the present invention to a specific embodiment, it can be understood to include all changes, equivalents, or substitutes included in the spirit and scope of the present invention.

In describing the present invention, terms such as first and second may be used to describe various elements, but the elements may not be limited by the terms. These terms may be used only for the purpose of distinguishing one component from another component. For example, without departing from the scope of the present invention, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element.

The term and/or may include a combination of a plurality of related listed items or any of a plurality of related listed items.

When a component is referred to as being "connected" or "connected" to another component, it is said that it is directly connected to or may be connected to the other component, but other components may exist in the middle. Can be understood. On the other hand, when a component is referred to as being "directly connected" or "directly connected" to another component, it may be understood that there is no other component in the middle.

The terms used in this document are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions may include plural expressions unless the context clearly indicates otherwise.

In this document, terms such as "comprises" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and one or more other features. It may be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof, does not preclude in advance.

Unless otherwise defined, all terms, including technical or scientific terms, used herein may have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms as defined in a commonly used dictionary may be interpreted as having a meaning consistent with the meaning in the context of the related technology, and unless explicitly defined in this application, interpreted as an ideal or excessively formal meaning. May not be.

In addition, the embodiments disclosed in this document are provided to more completely describe to those of ordinary skill in the art, and the shapes and sizes of elements in the drawings may be exaggerated for clearer explanation.

In describing the present invention in this document, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description may be omitted.

Various embodiments described in this document may be implemented in a recording medium that can be read by a computer or a similar device using software, hardware, or a combination thereof.

According to a hardware implementation, embodiments of the present invention include application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), and processors. (processors), controllers (controllers), micro-controllers (micro-controllers), microprocessors (microprocessors), it may be implemented using at least one of an electrical unit for performing a function.

Meanwhile, according to software implementation, embodiments such as procedures and functions in the present invention may be implemented together with separate software modules that perform at least one function or operation.

Hereinafter, the first direction (DR1) crosses (vertical) with the second direction (Second Direction, DR2) and the third direction (Third Direction, DR3), and the second direction (DR2) is the third direction (DR3). ) And can be intersected (vertically).

Here, the first direction DR1 and the second direction DR2 may be collectively referred to as a horizontal direction.

In addition, the third direction DR3 may be referred to as a vertical direction.

1 to 3 are views for explaining a non-destructive inspection apparatus using an acoustic signal according to the present invention.

Referring to FIG. 1, a non-destructive inspection apparatus 1A using an acoustic signal according to the present invention (hereinafter, may be referred to as an'inspection apparatus') includes a sensor unit 10 and a sensor unit for sensing information on an inspection object. A signal processing part (20) that processes information sensed by (10) may be included.

The sensor unit 10 may include a plurality of acoustic sensors (Acoustic Sensors 10a, 10b, 10c, 10d).

The plurality of acoustic sensors 10a, 10b, 10c, and 10d may be disposed on the inspection object 2A, as shown in FIG. 2. For example, at least one acoustic sensor 10a, 10b, 10c, and 10d may be disposed on the surface of the inspection object 2A.

The plurality of acoustic sensors 10a, 10b, 10c, and 10d may sense an acoustic signal generated from the test object 2A and transmit the sensed information to the signal processor 20. For example, a plurality of acoustic sensors (10a, 10b, 10c, 10d) is an acoustic signal generated during the operation of the inspection object (2A), that is, the operating sound (Operating Acoustic Signature) and during the non-operation of the inspection object (2A). A sound signal, that is, a non-operating sound (Non-Operating Acoustic Signature) may be sensed, and the sensed information may be transmitted to the signal processor 20.

Hereinafter, the test object 2A on which the acoustic sensors 10a, 10b, 10c, and 10d are disposed will be described with a pipe-shaped product as an example, but the present invention may not be limited thereto. For example, in the present invention, the inspection object 2A may correspond to various mechanical products such as a boiler and a generator.

However, considering that the abnormal location can be more effectively determined when the non-destructive inspection device is installed in the pipe of the power plant or the pipe of the boiler using the acoustic sensor according to the present invention, the inspection object 2A is a pipe-shaped pipe. It may be desirable.

The signal processing unit 2A may include an abnormality detection unit 21, a control unit 22, a communication unit 23, an output unit 24, an alarm unit 25, a memory unit 26, and an interface unit 27. .

The control unit 22 may control the overall operation and function of the inspection apparatus 1A according to the present invention.

For example, the control unit 22 may control processing of information sensed by the acoustic sensors 10a, 10b, 10c, and 10d, and control detection of an abnormal position of the inspection object 2A.

The abnormality detection unit 21 may detect the abnormal position of the inspection object 2A based on the sensing information by the acoustic sensors 10a, 10b, 10c, and 10d under the control of the controller 22.

The abnormality detection unit 21 may include an attenuation unit 100, a base amplitude unit 200, a heat map unit 300, and a detection unit 400.

The attenuating unit 100 may generate, manage, and store information on a signal attenuation characteristic of the test object 2A.

The signal attenuation characteristic of the test object 2A may be set based on each of the acoustic sensors 10a, 10b, and 10c 10d. In consideration of this, the attenuating unit 100 may correspond to information on signal attenuation based on each of the acoustic sensors 10a, 10b, and 10c 10d.

The attenuation unit 100 may include an attenuation rate unit 110 and a weight unit 120.

The attenuation rate unit 110 may generate, manage, and store information on the attenuation rate of the test object 2A.

Information on the attenuation rate of the inspection object 2A is set based on each of the acoustic sensors 10a, 10b, 10c, and 10d, and the attenuation rate may be determined differently according to a distance and/or direction. In consideration of this, the attenuation rate unit 110 may correspond to information on a signal attenuation rate according to a distance and/or a direction based on each of the acoustic sensors 10a, 10b, 10c, and 10d.

As shown in FIG. 3, the attenuation rate unit 110 may include a reference position unit 111 and an attenuation rate calculation unit 112.

The reference position unit 111 may generate, manage, and store information on a reference position (P) for detecting an abnormal position on the inspection object 2A. In other words, the reference position part 111 may correspond to a plurality of reference positions P on the inspection object 2A. For example, the reference position unit 111 may generate, manage, and store information on the number of reference positions, vertical and horizontal positions, and distances between reference positions.

The attenuation rate calculating unit 112 may calculate a signal attenuation rate of the test object 2A. In detail, the attenuation rate calculation unit 112 includes information on the direction of the reference position P based on the acoustic sensors 10a, 10b, 10c, and 10d, the reference position P, and the acoustic sensors 10a, 10b, 10c, and 10d. The signal attenuation rate for the inspection object 2A can be calculated based on the information on the distance between) and the information on the amplitude difference of the non-operating sound at the adjacent reference position P.

The weighting unit 120 of the attenuating unit 100 may generate, manage, and store information on the amplitude weight. In detail, the weighting unit 120 may set amplitude weights for a plurality of reference positions P on the inspection object 2A based on information on the signal attenuation rate calculated by the attenuation rate calculating unit 112.

The base amplitude unit 200 of the abnormality detection unit 21 may generate, manage, and store information corresponding to the base amplitude. In detail, the base amplitude unit 200 may set information on the base amplitude for each location where the acoustic sensors 10a, 10b, 10c, and 10d are installed.

The heat map unit 300 may create a heat map based on information generated by the attenuation unit 100 and the base amplitude unit 200. In detail, the heat map unit 300 includes information on the operating sound generated during operation of the test object 2A sensed by the acoustic sensors 10a, 10b, 10c, and 10d, and the base amplitude set by the base amplitude unit 200. And a heat map for the inspection object 2A based on the information on the signal attenuation set by the attenuating unit 100.

Here, a heat map is a word that combines heat meaning heat and map meaning map, and it can be said that various information that can be expressed in colors is output as a visual graphic in the form of heat distribution on a certain image. I can.

The detection unit 400 of the abnormality detection unit 21 may detect the abnormal position of the inspection object 2A from the heat map created by the heat map unit 300.

The communication unit 23 of the signal processing unit 20 may perform a communication function under the control of the control unit 22. For example, the communication unit 23 may perform communication with an external server and/or a terminal (not shown).

Alternatively, the communication unit 23 may be in charge of communication between the signal processing unit 20 and the sensor unit 10.

The output unit 24 may output predetermined information in the form of audio and/or video. For example, although not shown, the output unit 24 may include a display part, and a heat map created by the heat map unit 300 may be output on a screen so that a user can check it using such a display unit.

When an abnormal location is detected in the inspection object 2A, the alarm unit 25 may generate, manage, and store alarm information regarding the abnormal location.

The memory unit 26 may store information such as various data and programs required for operation of the inspection apparatus 1A according to the present invention.

The interface unit 27 may perform connection with an external device. For example, it is possible to connect a mobile terminal such as a smart phone to the signal processing unit 20.

The inspection method using the inspection apparatus 1A described above will be described in detail below with reference to the accompanying drawings.

4 to 13 are views for explaining a non-destructive inspection method using an acoustic signal according to the present invention. Hereinafter, descriptions of the parts described above may be omitted. The non-destructive inspection method using an acoustic signal described below may be implemented by the inspection apparatus 1A described above. The function and operation of the inspection device 1A will be clarified through the following description.

Referring to FIG. 4, in the non-destructive inspection method using an acoustic signal according to the present invention (hereinafter, it may be referred to as an'inspection method'), a plurality of acoustic sensors 10a, 10b, 10c, and 10d are first applied to the inspection object 2A. Can be installed (S100). An example of a method of installing the acoustic sensors 10a, 10b, 10c, and 10d on the inspection object 2A has been described in FIG. 2 above.

Thereafter, information on signal attenuation may be set based on the acoustic sensors 10a, 10b, 10c, and 10d installed in the test object 2A (S200).

The step of setting information on signal attenuation (S200) may include a step of setting a signal attenuation rate (S210) and a step of setting an amplitude weight (S220).

In the step of setting the signal attenuation rate (S210), information on the signal attenuation rate according to a distance and/or direction may be set based on each of the acoustic sensors 10a, 10b, 10c, and 10d.

In step S220 of setting the amplitude weight, the amplitude weights for the plurality of reference positions P may be set.

The step of setting information on the signal reduction (S200) will be described in more detail with reference to FIGS. 5 to 9.

Referring to FIG. 5, in the step of setting the signal attenuation rate (S210 ), at least one reference position P on the test object 2A may be set (S211 ). Here, the reference position P may be referred to as a position virtually set in order to set information on signal attenuation of the object 2A.

For example, as shown in FIG. 6, the acoustic sensor may include a first acoustic sensor 10a, a second acoustic sensor 10b, a third acoustic sensor 10c, and a fourth acoustic sensor 10d.

Here, the second acoustic sensor 10b is disposed adjacent to the first acoustic sensor 10a in a horizontal direction (the first direction DR1 or the second direction DR2), and the third acoustic sensor 10c is 1 is disposed adjacent to the acoustic sensor 10a in the vertical direction (the third direction DR3), and the fourth acoustic sensor 10d has the third acoustic sensor 10c and the horizontal direction (the first direction DR1 or the first They may be disposed adjacent to each other in two directions DR2. In addition, the fourth acoustic sensor 10d may be positioned adjacent to the second acoustic sensor 10b in a vertical direction (the third direction DR3).

Here, a plurality of reference positions P are set between the first acoustic sensor 10a and the second acoustic sensor 10b, and a plurality of reference positions P are set between the first acoustic sensor 10a and the second acoustic sensor 10b. The reference position P of may be set.

In addition, a plurality of reference positions P are set between the second acoustic sensor 10b and the fourth acoustic sensor 10d, and a plurality of reference positions P are also set between the third acoustic sensor 10c and the fourth acoustic sensor 10d. The reference position P of may be set.

The horizontal interval dh between adjacent reference positions P may be set equally. In addition, the vertical interval dv between adjacent reference positions P may be set equally. In this case, calculation may be easy.

Considering the shape, surface curvature, and size of the inspection target (2A), the horizontal distance (dh) between adjacent reference positions (P) is different from the horizontal distance (dh) between adjacent reference positions (P). It could also be possible. Of course, it may be possible to make the vertical distance dv between adjacent reference positions P different from the vertical distance dv between other adjacent reference positions P.

Hereinafter, for convenience of explanation and understanding, it is assumed that the horizontal distance dh between adjacent reference positions P is the same, and the vertical distance dv between adjacent reference positions P is the same. .

In FIG. 6, at least one of the acoustic sensors 10a, 10b, 10c, and 10d adjacent to each other in the horizontal direction (the first direction DR1 or the second direction DR2) or the vertical direction (the third direction DR3) Although only the case of setting the reference position P is described, the present invention may not be limited thereto. For example, as in the case of FIG. 7, at least one reference position P is set in a diagonal direction between the first acoustic sensor 10a and the fourth acoustic sensor 10d, and the second acoustic sensor 10b It may be possible to set at least one reference position P in a diagonal direction between the and the third acoustic sensor 10c.

In this way, after setting the reference position P in the inspection object 2A, as shown in FIG. 8, vibration (shock) may be applied to the reference position P. Then, the acoustic sensors 10a, 10b, 10c, and 10d may sense the acoustic signal generated by the vibration applied to the reference position P (S212).

In detail, vibration may be applied to each of the reference positions P in a state in which the inspection object 2A is not operated, that is, in a non-operating state. At this time, the generated sound signal may be referred to as a non-operating sound (Non-Operating Acoustic Signature). In consideration of this, it can be seen that the acoustic sensors 10a, 10b, 10c, and 10d sense the non-operation sound generated at the reference position P of the test object 2A.

In FIG. 8, the movement of the non-operation sound occurring at a predetermined reference position P is indicated by arrows.

Thereafter, a signal attenuation rate may be calculated in consideration of distance information, direction information, and information about an amplitude difference (S213).

In detail, information on the direction of the reference position (P) based on the acoustic sensors (10a, 10b, 10c, 10d), and the distance between the reference position (P) and the acoustic sensors (10a, 10b, 10c, 10d). The signal attenuation rate for the inspection object 2A can be calculated based on the information and information on the amplitude difference of the non-operational sound at the adjacent reference position P.

If this calculation method is summarized by Equation, it may correspond to Equation 1 (Eq 1) shown in FIG. 8.

In Equation 1, r is the attenuation rate, n is the number of reference positions (P), d is the distance between the reference positions (P), and A _i is the acoustic signals 10a, 10b, 10c, and 10d acquired from the i-th acoustic sensor. Can mean the amplitude of ).

The result calculated according to Equation 1 may be set as the signal attenuation rate of the object 2A (S214).

Referring to FIG. 9, when the inspection object 2A has a pipe shape such as a pipe, the signal attenuation pattern is in the vertical direction (the third direction DR3) and the signal attenuation pattern is in the horizontal direction (the first direction DR1 or the second direction DR2). )) can be more stable compared to the signal attenuation pattern. In other words, the signal attenuation pattern in the vertical direction (the third direction DR3) can be said to be relatively linear compared to the signal attenuation pattern in the horizontal direction (the first direction DR1 or the second direction DR2). .

In consideration of this, the distance dh between the reference positions P in the horizontal direction (the first direction DR1 or the second direction DR2) in order to more accurately detect the abnormal position in the inspection object 2A, that is, The vertical distance dh may be smaller than the distance dv between the reference positions P in the vertical direction (the third direction DR3), that is, the vertical distance dv.

In other words, the reference position P in the horizontal direction can be set more densely than in the vertical direction.

In this way, in the step of setting information on signal attenuation (S200), information on the amplitude weight may be set (S220) after the signal attenuation rate of the object 2A is calculated and set.

In detail, in the step of setting the amplitude weight (S220), the amplitude weights for the plurality of reference positions P on the inspection object 2A may be set based on the information on the signal attenuation rate set by the method described in detail above. .

The amplitude weight may be set based on each of the acoustic sensors 10a, 10b, 10c, and 10d. In addition, the amplitude weight may have a pattern that decreases as the distance from the acoustic sensors 10a, 10b, 10c, and 10d increases.

For example, as in the case of FIG. 10, the amplitude weight corresponding to the reference position P is 1, 0.8, 0.6, 0.4 as the distance increases based on the respective acoustic sensors 10a, 10b, 10c, and 10d. It is possible to have the value of

If vibration occurs at a position close to the first acoustic sensor 10a, the amplitude of the acoustic signal sensed by the first acoustic sensor 10a is relatively large, but on the contrary, the second acoustic sensor 10b and the third acoustic The amplitude of the acoustic signal sensed by the sensor 10c and/or the fourth acoustic sensor 10d may be relatively small.

In consideration of this, it may be desirable to separately set an amplitude weight for each of the acoustic sensors 10a, 10b, 10c, and 10d.

If the method of calculating the amplitude weight is summarized in Equation, it may correspond to Equation 2 (Eq 2) posted in FIG. 10.

In Equation 2, E _i is the amplitude weight, x and y are the target positions, x _i and y _i are the positions of the i-th acoustic sensor, r _h is the signal attenuation rate in the horizontal direction, and r _v is the signal attenuation rate in the vertical direction. Can mean

The result calculated according to Equation 2 may be set as an amplitude weight (S220).

Base amplitude information may be set (S300) after the step of setting information on signal attenuation (S200) described above. In detail, information on the base amplitude may be set for each location where the acoustic sensors 10a, 10b, 10c, and 10d are installed.

Here, the base amplitude information may mean an amplitude of an acoustic signal generated during the normal operation of the test object 2A. In other words, the base amplitude information may mean the background sound (background noise) of the inspection object 2A.

In order to set the information on the base amplitude, test operation may be performed for a predetermined time before normal operation of the inspection object 2A.

It is possible to sense the acoustic signal generated during the test operation period, and to set information on the amplitude of the sensed acoustic signal as information on the base amplitude.

Then, the operating sound (Operating Acoustic Signature) may be sensed (S400).

The operating sound may mean an acoustic signal generated in an operating state in which the test object 2A is normally operated.

Up to the step (S300) of setting information on the base amplitude described above may be regarded as a preparatory step (test step or setup step) before normal operation of the inspection target 2A.

In addition, after step S300 may be referred to as an operation step.

In consideration of this, it can be seen that the operation sound is sensed by using the acoustic sensors 10a, 10b, 10c, and 10d while normally operating the inspection target 2A in the operation stage after the preparation stage.

Thereafter, the signal processing unit 20 may create a heat map based on the information on the operating sound sensed by the acoustic sensors 10a, 10b, 10c, and 10d (S500).

In detail, the heat map unit 300 of the signal processing unit 20 may create a heat map for the inspection object 2A based on the information on the operating sound, the base amplitude, and the signal attenuation.

11 shows an example of a heat map.

As shown in FIG. 11, the heat map may have a visual image form in the form of a heat distribution.

If the method of creating such a heat map is summarized in an equation, it may correspond to equation 3 (Eq 3) posted in FIG. 11.

In Equation 3, H(x, y) is the heat map value of x and y coordinates, E _i (X, Y) is the amplitude weight for the x and y coordinates of the ith acoustic sensor, and A _i is the ith acoustic sensor The amplitude of the signal acquired from, B _i, may mean the base amplitude of the i-th acoustic sensor.

In Equation 4, i is set from 1 to 4 assuming that the number of acoustic sensors is four. When the number of acoustic sensors is changed, the range of the i value may also be changed.

A heat map may be created using the result calculated according to Equation 3, and the created heat map may be converted into an R, G, and B color image and output to be checked on the screen (S600).

The user (operator, manager) can accurately check the location where the leak or crack occurred in the inspection target 2A, that is, the abnormal location by looking at the output heat map.

In addition, the user can use the output heat map to identify the type of abnormality, for example, whether a leak has occurred or whether a crack has not occurred but damage has been accumulated.

As described above, in the non-destructive inspection apparatus and inspection method using an acoustic signal according to the present invention, not only can the abnormal location of the inspection object 2A be accurately identified, but also the type or degree of the abnormality can be easily confirmed by using a heat map.

A heat map of the relatively normal inspection object 2A is posted in Fig. 12A, and a heat map of the inspection object 2A in which an abnormality has occurred is posted in Fig. 12B.

When (A) and (B) of FIG. 12 are compared, (A) shows that the heat distribution is relatively even, and (B) shows that the heat distribution is skewed to the lower right on the heat map.

12B may mean that there is an abnormality such as leakage occurring in the lower right portion of the heat map.

In addition, the type or degree of abnormality can be easily identified from the color on the heat map. For example, if the color of a specific part on the heatmap is close to red, that part means that the change in the attenuation rate of the signal is greater, which may mean that the damage of the part is greater than that of other parts .

Meanwhile, after the heat map creation step (S500), the detection unit 400 of the signal processing unit 20 analyzes the created heat map to automatically detect an abnormality in the inspection target 2A (S700).

For example, the detection unit 400 may analyze a heat map to generate information on an abnormal location, an abnormality type, and an abnormality degree.

Referring to FIG. 13, it is assumed that the color of the lower right of the heat map unit 300 is close to yellow as shown in (A).

In this case, the detection unit 400 may generate information that there is an abnormality in the lower right corner of the heat map by analyzing the heat distribution and color of the heat map.

Then, the alarm unit 25 of the signal processing unit 20 may output alarm information in response to information generated by the detection unit 400.

An example of information on abnormality detection generated by the detection unit 400 is posted in FIG. 13B.

12 to 13 are for explaining an example of a heat map and an example of detection information, and the present invention may not be limited thereto.

As described above, it will be understood that the technical configuration of the present invention described above can be implemented in other specific forms without changing the technical spirit or essential features of the present invention by those skilled in the art.

Therefore, the above-described embodiments are to be understood as illustrative and not limiting in all respects, and the scope of the present invention is indicated by the claims to be described later rather than the detailed description described above, and the meaning and scope of the claims And all changes or modified forms derived from the equivalent concept should be interpreted as being included in the scope of the present invention.

1A: Non-destructive inspection device
2A: Inspection target
10: sensor unit
20: signal processing unit
10a, 10b, 10c, 10d: acoustic sensor
21: abnormality detection unit
22: control unit
23: communication department
24: output
25: alarm unit
26: memory unit
27: interface unit
100: attenuation part
111: reference position part
112: attenuation rate calculation unit
200: base amplitude part
300: heat map section
400: detection unit

Claims (10)

Setting information on signal attenuation, respectively, based on a plurality of acoustic sensors installed in the test object;
Setting information on the base amplitude for each location where the acoustic sensor is installed;
Sensing, by the acoustic sensor, an operating sound generated during operation of the test object; And
Outputting a heat map for the inspection object created based on the operating sound, information on the base amplitude, and information on the signal attenuation;
Non-destructive inspection method using an acoustic signal comprising a. The method of claim 1,
Setting the information on the signal attenuation comprises:
Setting information on a signal attenuation rate according to a distance and/or a direction based on each of the acoustic sensors; And
Setting amplitude weights for a plurality of reference positions on the inspection object based on the information on the signal attenuation rate;
Non-destructive inspection method using an acoustic signal comprising a. The method of claim 2,
Setting information on the signal attenuation rate comprises:
Setting a plurality of the reference positions on the inspection object;
Sensing, by each of the acoustic sensors, a non-operation sound generated at the reference position in a non-operation state of the test object; And
Based on the information on the direction of the reference position with respect to the acoustic sensor, information on the distance between the reference position and the acoustic sensor, and information on the amplitude difference of the non-operating sound at the adjacent reference position, the Calculating the signal attenuation rate for the test object;
Non-destructive inspection method using an acoustic signal comprising a. The method of claim 3,
The acoustic sensor
A first acoustic sensor, a second acoustic sensor adjacent to the first acoustic sensor in a horizontal direction (Horizontal Direction) and a third acoustic sensor adjacent to the first acoustic sensor in a vertical direction (Vertical),
A plurality of the reference positions are set between the first acoustic sensor and the second acoustic sensor,
A non-destructive inspection method using an acoustic signal, characterized in that a plurality of the reference positions are set between the first acoustic sensor and the third acoustic sensor. The method of claim 1,
Non-destructive inspection method using an acoustic signal, characterized in that the step of detecting the abnormal position of the inspection object from the heat map. A plurality of acoustic sensors installed on the test object;
An attenuator configured to set information on signal attenuation based on each of the acoustic sensors;
A base amplitude unit configured to set information on a base amplitude for each location in which the acoustic sensor is installed; And
A heat map unit for creating a heat map for the inspection object based on the operation sound generated during operation of the inspection object sensed by the acoustic sensor, information on the base amplitude, and information on the signal attenuation;
Non-destructive inspection device using an acoustic signal comprising a. The method of claim 6,
The attenuation unit
An attenuation rate unit for setting information on a signal attenuation rate according to a distance and/or direction based on each of the acoustic sensors; And
A weighting unit configured to set amplitude weights for a plurality of reference positions on the test object based on information on the signal attenuation rate;
Non-destructive inspection device using an acoustic signal comprising a. The method of claim 7,
The attenuation rate part
A reference position unit for setting a plurality of reference positions on the inspection object; And
The inspection based on information on the direction of the reference position with respect to the acoustic sensor, information on the distance between the reference position and the acoustic sensor, and information on the amplitude difference of the non-operating sound at the adjacent reference position An attenuation rate calculator that calculates the signal attenuation rate for an object;
Including,
The non-operational sound is a non-destructive inspection apparatus using an acoustic signal, characterized in that the sound signal generated at the reference position in the non-operation state of the test object. The method of claim 8,
The acoustic sensor
A first acoustic sensor, a second acoustic sensor adjacent to the first acoustic sensor in a horizontal direction (Horizontal Direction) and a third acoustic sensor adjacent to the first acoustic sensor in a vertical direction (Vertical),
A plurality of the reference positions are set between the first acoustic sensor and the second acoustic sensor,
A non-destructive testing apparatus using an acoustic signal, characterized in that a plurality of the reference positions are set between the first acoustic sensor and the third acoustic sensor. The method of claim 9,
Non-destructive inspection apparatus using an acoustic signal, characterized in that it further comprises a detection unit for detecting the abnormal position of the inspection object from the heat map.

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