WO2016017991A1

WO2016017991A1 - Nondestructive fatigue inspection apparatus and inspection method therefor using electromagnetic induction sensor

Info

Publication number: WO2016017991A1
Application number: PCT/KR2015/007662
Authority: WO
Inventors: 박정웅; 김국주; 김준석; 정민식; 홍동기
Original assignee: (주)라디안; 조선대학교산학협력단
Priority date: 2014-07-28
Filing date: 2015-07-23
Publication date: 2016-02-04
Also published as: KR20160013750A; KR101936367B1

Abstract

The present invention is to accurately measure a degree of fatigue, and the aim of the present invention is to easily carry out degree of fatigue inspection using an electromagnetic induction sensor that is a kind of nondestructive inspection. To achieve the aim, according to an embodiment of the present invention a degree of fatigue inspection apparatus using an electromagnetic induction sensor unit is disclosed. The inspection apparatus may comprise: a probe unit including an electromagnetic induction sensor unit having an electromagnetic induction coil thereinside for transmitting magnetic flux lines generated from the electromagnetic induction coil into the inspection region and then receiving the same, and an acceleration sensor for measuring the measurer's hand-vibrations; a control unit for applying the hand-vibration information measured by the acceleration sensor to the received magnetic flux line information; and a display unit for displaying the magnetic flux line information to which the hand-vibration information is applied.

Description

Nondestructive Fatigue Testing Device Using Electromagnetic Induction Sensor and Its Inspection Method

The present invention relates to a non-destructive fatigue testing apparatus and an inspection method using an electromagnetic induction sensor, and more specifically, to a non-destructive inspection method according to the material of welding, joint sites, such as ships, vehicles, large structures, etc. by using the electromagnetic induction sensor The present invention relates to an apparatus for inspecting fatigue and a method of inspecting the same.

For example, a ship's structure is very complicated due to various wave loads generated by the natural environment even if its route is determined. Therefore, it is very difficult to accurately predict the degree of damage to the load under these operations. Since a ship accident can lead to a large-scale human accident, property damage, etc., it is very important to accurately predict the fatigue level of the ship structure and to determine the ship's life and safety diagnosis time.

As such, the following non-destructive testing methods may be used to measure the fatigue of a ship structure.

1. In the non-destructive testing (RT) method, the principle is to use the difference in the concentration on the film due to the change in the intensity of the transmitted radiation when the product is irradiated with transparent radiation, that is, the difference in the amount of transmission lines between the sound and defect parts. It is a method to inspect the product for defects. In the case of this inspection method, only the highly trained technicians can use the radiation itself in accordance with the National Radiation Dangerous Goods Handling and Management Regulation, and it is difficult to handle and increases the time and cost. It can't be done.

2. In the case of Ultrasonic Testing (UT), the principle is that the ultrasonic energy is transmitted to the product, and the amount of ultrasonic energy reflected from the discontinuous parts existing inside, the progress time of the ultrasonic wave, etc. It is one of the most widely used nondestructive testing methods in the world. However, this method also needs to be measured by applying a gel to the ultrasonic transducer to minimize the loss of ultrasonic energy, and the distortion of the data is influenced by the influence of the amount of gel applied, the measuring angle and position of the transducer, and the surrounding environment and temperature. Due to this, there is a limitation that it is difficult to apply to measure the fatigue of the ship.

3. The principle of magnetic particle nondestructive testing (MT) is to magnetize a ferromagnetic substance and apply magnetic powder to collect or blow the magnetic field by leakage magnetic field to detect the discontinuity (defect) on or under the ferromagnetic body. It is possible to measure cracks on the surface only by checking the location, size, shape and width of the surface.

4. The principle of Penetration Testing Nondestructive Testing (PT) is that the developer does not penetrate into the discontinuities (defects) after sufficient time has passed after applying the penetration liquid to the surface of the product, and removes the excess penetrant remaining on the surface of the test object. Is a method of detecting the location, size, and indication of a defect by sucking up the penetrant. This method also can measure only the defects on the surface of the product, and it is not possible to apply the numerical value of the data, making it difficult to apply the ship fatigue test.

5. The principle of eddy current non-destructive testing (ET) is to bring the alternating current of eddy current inside the conductor when it is brought close to the test object such as metal, and the eddy current is changed in size and distribution by the influence of defect or material. It is a test method to measure cracks or defects on the surface of an object by measuring the amount of change. However, this also has the disadvantage that it is difficult to determine the exact fatigue because the surface inspection is possible, but the inspection of the inner and deep parts of the product is impossible.

According to the prior art (Korean Patent Publication No. 10-2009-0066853), it is used in a fatigue tester for performing a fatigue test on the ship membrane fatigue specimen, located on one side of the fatigue specimen, toward the fatigue specimen Lighting devices for illuminating light; And an optical sensing device positioned to face the lighting device with the fatigue test piece interposed therebetween, the optical sensing device sensing the light of the lighting device through the cracking of the fatigue test piece. And a control computer for receiving a signal and for transmitting a shutdown signal of the fatigue tester to the fatigue tester, wherein the light sensing device is a fatigue crack detection device that is a CCD camera.

However, even by such a conventional technology, it is difficult to accurately measure the fatigue according to the thickness and depth of the test object by detecting fatigue using a CCD camera.

The present invention is to accurately measure the fatigue level of a ship, a vehicle, a large building, etc., and an object of the present invention is to easily perform the fatigue test using an electromagnetic induction sensor which is a kind of non-destructive test.

According to one embodiment of the present invention, a fatigue inspection apparatus utilizing the electromagnetic induction sensor unit is disclosed. The inspection apparatus includes an electromagnetic induction coil and a probe unit including an electromagnetic induction sensor unit for transmitting and receiving a magnetic flux line generated by the electromagnetic induction coil to the inspection site, and an acceleration sensor unit for measuring and correcting the shaking of the measurer. ; A control unit for reflecting the hand shake information measured by the acceleration sensor in the received information on the magnetic flux lines; And a display unit for displaying the information on the magnetic flux lines in which the hand shake information is reflected.

The inspection apparatus may be configured to determine a degree of fatigue based on a specimen in a normal state so as to pre-measure a reference specimen having the same material and composition as the measurement specimen, to store data or to store a standard specimen of the measurement object in a space; And a reference sensor unit including a reference sensor for measuring the specimen in the steady state.

The controller may automatically determine the frequency of the magnetic flux line passing through the inspection region according to the material, thickness, or temperature of the inspection region by automatically changing the frequency of the magnetic flux line within a predetermined range after a start of inspection. Algorithm analysis software may be further included.

According to another embodiment of the present invention, a fatigue test method using the electromagnetic induction sensor unit is disclosed. The inspection method may include receiving and transmitting a flux line using an electromagnetic induction sensor unit included in the probe unit with respect to the inspection site; Measuring a camera shaker using an acceleration sensor included in the probe unit; Reflecting the hand shake information measured by the acceleration sensor in the received information on the magnetic flux lines by a controller; And determining, by the controller, whether the inspection site is normal by comparing the information on the magnetic flux line in which the hand shake information is reflected with the information on the magnetic flux line of the specimen in the normal state measured by the reference sensor.

The inspection method may further include displaying information on a magnetic flux line reflecting the hand shake information on a display unit.

The present invention can easily inspect the fatigue degree of the welding, joining portion, etc. of the ship, vehicle, large structure, etc. by utilizing the electromagnetic induction sensor.

1 shows a schematic diagram of a fatigue testing apparatus according to an embodiment of the present invention.

Figure 2 shows a conceptual diagram of the fatigue test apparatus according to an embodiment of the present invention.

FIG. 3A illustrates a state in which a magnetic flux line is generated by an electromagnetic induction sensor and transmitted after receiving the object to be inspected without fatigue and cracks according to an embodiment of the present invention.

3B illustrates a state in which a magnetic flux line is generated by an electromagnetic induction sensor and transmitted after being transmitted to an inspection object in which fatigue and cracks exist, according to an embodiment of the present invention.

4A and 4B illustrate graphs displayed on the display unit according to an embodiment of the present invention.

5 shows a flowchart of a fatigue test method according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail a vacuum cassette according to an embodiment of the present invention. The present invention may be modified in various ways and may have various forms (pen type, donut shape, horseshoe shape, etc.), and specific embodiments will be illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention. In describing the drawings, similar reference numerals are used for similar elements. In the accompanying drawings, the dimensions of the structures are shown in an enlarged scale than actual for clarity of the invention.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, action, component, part, or combination thereof described on the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Referring to FIG. 1, a fatigue test apparatus using an electromagnetic induction sensor unit includes a probe 101 and a main body 102. The measurer who wants to check the fatigue carries the fatigue test apparatus, scans the inspection site using the probe 101, transmits and receives the magnetic flux lines, displays the magnetic field information on the main body 102, and checks the normality of the inspection site. Determine whether or not.

Detailed configuration of the fatigue test apparatus will be further described below with reference to FIG. 2.

The fatigue test apparatus includes an acceleration sensor 201 for measuring a hand shake of an operator and an electromagnetic induction coil therein, and an electromagnetic induction sensor unit for receiving the magnetic flux lines generated by the electromagnetic induction coil after passing through the inspection part ( A probe unit 203 including 202; A control unit 204 for reflecting the hand shake information measured by the acceleration sensor in the received information on the magnetic flux lines; And a display unit 205 for displaying information on the magnetic flux lines in which the hand shake information is reflected.

If hand shake occurs when the tester scans the inspection site with the probe 203, an error may occur in the magnetic flux line received by the electromagnetic induction sensor 202. Therefore, it is necessary to correct the camera shake. In the present invention, by including the acceleration sensor 201 for measuring the hand shake of the measurer, by measuring the hand shake of the measurer can be used to correct the error of the magnetic flux lines due to hand shake.

The electromagnetic induction sensor unit 202 includes an electromagnetic induction coil therein and transmits the magnetic flux lines generated by the electromagnetic induction coil to the inspection site and receives the magnetic flux lines.

The controller 204 corrects an error due to hand shake by reflecting the hand shake information measured by the acceleration sensor 201 in the information on the magnetic flux lines received by the electromagnetic induction sensor unit 202.

The information on the magnetic flux lines whose error due to the hand shake is corrected by the controller 204 is displayed on the display unit 205.

The inspection apparatus includes a space 206 for receiving a specimen (standard specimen) in a steady state; And a reference sensor unit 208 including a reference sensor 207 for measuring the specimen in the steady state.

In order to determine whether fatigue is normal or abnormal, information about a magnetic flux line when a test region currently being scanned by a probe is in a normal state and information about a magnetic flux line of an inspection region currently being scanned by a probe is required.

The inspection apparatus includes a reference sensor unit 208 in order to obtain information on the magnetic flux lines in such a steady state. The reference sensor unit 208 is provided with a space 206 for accommodating the specimen in a steady state. A specimen (for example, iron, SUS, aluminum, cast iron, copper, etc.) of the same material as that of the material to be tested for fatigue is stored in the space 206 and the information of the magnetic flux lines in the normal state is measured by the reference sensor 207. can do.

The display unit 205 may display information on the magnetic flux lines of the inspection site and information on the magnetic flux lines of the specimen in the normal state.

FIG. 3A illustrates a state in which a magnetic flux line is generated by an electromagnetic induction sensor and transmitted after receiving the object to be inspected without fatigue in accordance with an embodiment of the present invention.

Referring to FIG. 3A, the magnetic flux lines output from the electromagnetic induction sensor unit 202 are received by the electromagnetic induction sensor unit 202 after passing through the inspection object 302. In FIG. 3A, since there are no irregularities such as fatigue, cracks, and plating peeling on the inspection object, the appearance of the magnetic flux lines is not changed and is received by the electromagnetic induction sensor unit 202.

The flux line transmitted to the inspection object is received by the electromagnetic induction sensor unit 202 when the appearance of the flux line is changed when there is a non-uniformity such as cracks, fatigue, plating peeling, etc. in the inspection object.

3B illustrates a state in which a magnetic flux line is generated by an electromagnetic inductive sensor and transmitted after being transmitted to an inspection object in which fatigue, cracks, etc. are present, according to an embodiment of the present invention.

Referring to FIG. 3B, the magnetic flux lines output from the electromagnetic induction sensor unit 202 are received by the electromagnetic induction sensor unit 202 after passing through the inspection object 302. In FIG. 3B, since irregularities such as cracks, fatigue, plating peeling, and the like exist in the inspection object, the state of the magnetic flux lines is changed and received by the electromagnetic induction sensor unit 202.

By analyzing the amplitude and phase difference of the voltage generated in the electromagnetic induction coil by the magnetic flux lines received by the electromagnetic induction sensor unit 202, it is determined whether there is a non-uniform phase such as crack, fatigue, plating peeling, etc. You can decide whether or not you pass.

For example, it can be determined that the voltage of the normal region obtains the amplitude and phase graph in advance, and based on this, the fatigue is large when a difference over the predetermined range occurs in the amplitude and phase graph of the voltage.

The magnetic flux line can be changed by adjusting the shape and number of turns of the electromagnetic induction coil in the electromagnetic induction sensor unit 202 or by adjusting the current applied to the electromagnetic induction coil, and adjust the transmission distance to the inspection object according to the change of the magnetic flux line. Can be.

The controller 204 may automatically determine the frequency of the magnetic flux line passing through the inspection region according to the material, thickness, or temperature of the inspection region by changing the frequency of the magnetic flux line within a predetermined range after a start of inspection. have.

For example, the controller 204 may automatically determine the most suitable frequency for inspecting the inspection site by sequentially changing the frequency of the magnetic flux line of the electromagnetic induction sensor unit 202 from 10 hz to 1000 MHz.

The controller 204 may process the display unit 205 to display information on the magnetic flux lines. For example, the control unit 204, on the display unit 205, sets the x-axis as the rotation angle of the inspection object from the reference point, and displays a graph on the y-axis of the voltage generated in the electromagnetic induction coil by the received magnetic flux lines. It is possible to process the voltage information of the magnetic flux lines received so as to.

Referring to FIG. 4A, in the graph, the x-axis represents the distance scanned by the inspection object, and the y-axis represents the voltage generated in the magnetic induction coil by the magnetic flux lines received from the electromagnetic induction sensor unit.

The graph indicated by 401 is the output waveform of the normal region measured in advance or measured by the reference sensor unit, and the graph indicated by 402 is the output waveform of the fatigue region, indicated by 402 because there is a difference between the predetermined reference in amplitude and phase. The test object generating the graph is divided into fatigue sites.

Referring to FIG. 4B, a graph in which the difference between the phase and the amplitude of the graph of the normal region and the fatigue region is converted into an absolute value is illustrated in FIG. 4A.

If the phase difference and amplitude difference between the voltage-distance graphs of the normal and fatigue parts according to the angles obtained in FIG. 4A are numerically expressed and displayed in a graph as in FIG. 4B, within a specific numerical value (for example, 1.0 to -1.0) The portion where the value is displayed did not cause fatigue of the welded portion, and the portion that deviates from it may be determined that the fatigue of the welded portion occurs.

For example, in the graph of FIG. 4B, the portions corresponding to 1 to 3, 6 to 14, and the like have a y value between 1.0 and -1.0, and thus this portion may be judged to have no fatigue of the welded portion. However, since

parts

4 and 15 have y values outside of 1.0 to -1.0, it can be determined that fatigue occurs at the welded part.

Therefore, according to the above graph, the fatigue part can be judged, and when the fatigue degree of the regularly occurring part is measured, cracks are generated due to the breakdown due to fatigue at some point. It can be replaced.

In FIG. 4B, the y value reflects, for example, the phase difference and amplitude difference of the voltage-distance graph at 1: 1, and sets the value of y to 1.0 when the phase difference is +20 degrees and the amplitude difference is +0.001 volt. You can decide.

This is merely an example, and the above values may be freely determined depending on the type of weldment, the field in which the weldment is to be used, and the like.

Although the x-axis is shown in FIG. 4A and 4B as distance, this may be time or the like. Even in the case of time, converting the data of FIG. 4A to the data of FIG. 4B can be easily converted according to a desired setting.

5 shows a flowchart of a method for checking fatigue quality according to an embodiment of the present invention.

Referring to FIG. 5, first, a magnetic flux line is transmitted through a magnetic flux line by using an electromagnetic induction sensor unit included in a probe unit, and then received (1). Then, measuring the hand shake of the measurer using the acceleration sensor included in the probe unit (2). Next, the control unit 3 includes reflecting the hand shake information measured by the acceleration sensor in the received information on the magnetic flux lines.

Finally, the step (4) of determining whether the inspection site is normal by comparing the information on the magnetic flux line reflecting the hand shake information with the information on the magnetic flux line of the specimen of the normal state measured by the reference sensor by the control unit can do.

The inspection method may further include the step (5) of displaying the information on the magnetic flux line reflecting the hand shake information on the display unit.

Prior to step (1), the method may further include automatically determining to transmit the magnetic flux lines at a frequency most suitable for the inspection site by automatically changing a frequency within a predetermined range for a predetermined time.

The description of the presented embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the scope of the invention. Thus, the present invention should not be limited to the embodiments set forth herein but should be construed in a scope consistent with the principles and novel features set forth herein.

The present invention has high applicability in the field of nondestructive fatigue testing.

Claims

As a fatigue test device using the electromagnetic induction sensor,

A probe unit including an electromagnetic induction coil inside the sensor and including an electromagnetic induction sensor unit for transmitting and receiving a magnetic flux line generated by the electromagnetic induction coil to an inspection part and an acceleration sensor for measuring a hand shake of the measurer;

Control unit for reflecting the hand shake information measured by the acceleration sensor to the information on the received magnetic flux line

A display unit for displaying information on a magnetic flux line reflecting the hand shake information;

To include, fatigue testing device utilizing the electromagnetic induction sensor unit.
The method of claim 1,

A space for storing specimens in the same steady state as the material to be measured; And a reference sensor for measuring the specimen in the steady state

Further comprising a reference sensor unit comprising a, fatigue testing device utilizing the electromagnetic induction sensor unit.
The method of claim 1,

The control unit,

Algorithm analysis software for automatically determining the frequency of the magnetic flux lines passing through the inspection site according to the material, thickness or temperature of the inspection site by changing the frequency of the magnetic flux lines within a predetermined range for a predetermined time after the start of inspection. Fatigue testing device.
As a fatigue test method using the electromagnetic induction sensor,

Receiving after transmitting the magnetic flux lines with respect to the inspection site using the electromagnetic induction sensor unit included in the probe unit;

Measuring a camera shaker using an acceleration sensor included in the probe unit;

Reflecting the hand shake information measured by the acceleration sensor in the received information on the magnetic flux lines by a controller; And

Determining whether the inspection site is normal by comparing the information on the magnetic flux line reflecting the hand shake information with the information on the magnetic flux line of the specimen in the normal state measured by the reference sensor by the controller;

To include, fatigue inspection method utilizing the electromagnetic induction sensor unit.
The method of claim 4, wherein

And displaying information on the magnetic flux lines in which the hand shake information is reflected, on a display unit.