Electromagnetic ultrasonic inspection equipment

Abstract

To provide an electromagnetic ultrasonic probe capable of performing flaw detection scanning of a subject in a direction vertical to a magnet arrangement direction.SOLUTION: An electromagnetic ultrasonic probe 10 comprises: a magnet array 13 including multiple magnets 11 which are arranged in an axial direction of piping 1 and alternately arranged to allow a radially outer side of the piping 1 to be an N pole or an S pole; and coils 14A-14D wound around the magnetic array 13 with the circumferential direction of the piping 1 as a center axis and mutually separated in the circumferential direction of the piping 1.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an electromagnetic ultrasonic probe. Child This invention relates to an electromagnetic ultrasonic inspection device equipped with the same. [Background technology]

[0002] Methods for performing flaw detection inspection of a test object using ultrasonic waves include a method using an ultrasonic probe and a method using an electromagnetic ultrasonic probe (see, for example, Patent Document 1).

[0003] The ultrasonic probe has a piezoelectric element that converts between an electric signal and an ultrasonic wave, and is in contact with the surface of the test object via a couplant. The ultrasonic probe transmits ultrasonic waves to the test object via the couplant and receives ultrasonic waves reflected by defects (more specifically, cracks, etc.) inside the test object via the couplant.

[0004] The electromagnetic ultrasonic probe of Patent Document 1 includes a magnet array having a plurality of magnets and one coil wound around the magnet array.

[0005] The multiple magnets are arranged in two rows in one direction along the surface of the subject. More specifically, the magnets in the first row are arranged so that one side in the direction perpendicular to the surface of the subject is the north pole and the other side is the south pole. The magnets in the second row are arranged so that one side in the direction perpendicular to the surface of the subject is the south pole and the other side is the north pole. The magnets in the first row and the magnets in the second row are arranged so that they alternate in the one direction. Therefore, the multiple magnets are arranged alternately so that one side in the direction perpendicular to the surface of the subject is the north pole or the south pole. This generates a static magnetic field (periodic magnetic field) in which the direction of the magnetic field alternates in the direction perpendicular to the surface of the subject.

[0006] The coil is wound around the magnet array along the surface of the subject and with its central axis in another direction perpendicular to the one direction (in other words, the direction in which the magnets are arranged).

[0007] The flaw detection device applies a transmission signal (pulse signal) to the coil of the electromagnetic ultrasonic probe, generating an eddy current in the surface layer of the object being inspected, which the coil faces. Then, due to the interaction between this eddy current and the static magnetic field created by multiple magnets, ultrasonic waves are generated in the surface layer of the object being inspected. These ultrasonic waves are propagated in the direction of the magnet arrangement at a transmission angle (specifically, an oblique angle relative to the thickness direction of the object being inspected), are reflected by defects inside the object, and return to the surface layer of the object being inspected. The flaw detection device obtains a reception signal (waveform signal) generated in the coil by the returning ultrasonic waves, by the reverse action of the above-mentioned action. This allows defects in the object to be detected. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-081235 Summary of the Invention [Problem to be solved by the invention]

[0009] Electromagnetic ultrasonic probes are expected to be fixed around pipes, for example, and to perform flaw detection inspections of pipes during operation (more specifically, when high-temperature fluid is flowing, for example). When using ultrasonic probes, it is necessary to maintain contact between the surface of the pipe and the probe, for example, by using an adhesive as a contact medium, but this is not necessary when using electromagnetic ultrasonic probes. Furthermore, if a highly heat-resistant magnet (more specifically, a samarium-cobalt magnet, for example) is used for the electromagnetic ultrasonic probe, the probe can be placed even in high-temperature environments of 200 to 300°C.

[0010] The electromagnetic ultrasonic probe of Patent Document 1 can perform flaw scanning of the subject in one direction of the probe (in other words, the magnet arrangement direction) by varying the frequency of the transmission signal applied to the coil to change the transmission angle of the ultrasonic waves. However, it cannot perform flaw scanning of the subject in other directions of the probe (in other words, the direction perpendicular to the magnet arrangement direction). Therefore, if the position of the probe is fixed, the inspection range of the probe is limited.

[0011] The object of the present invention is to provide a method for detecting flaws in a test object in a direction perpendicular to the direction of magnet arrangement. Ruden To provide a magnetic ultrasonic inspection device. [Means for solving the problem]

[0012] In order to achieve the above object, the present invention Electromagnetic ultrasonic inspection equipment a magnet array having a plurality of magnets arranged in one direction along the surface of the subject, and arranged alternately so that one side of the direction perpendicular to the surface of the subject becomes a north pole or a south pole. , and A plurality of coils are wound around the magnet array along the surface of the subject and with a central axis in another direction perpendicular to the one direction, and are spaced apart from each other in the other direction. Lu Preparation and a flaw detection device that selects a combination of a transmitting coil and a receiving coil from the plurality of coils, thereby recording a plurality of receiving signals corresponding to the combination of the transmitting coil and the receiving coil. [Effects of the Invention]

[0013] Original Clearly This allows flaw detection scanning of the subject in a direction perpendicular to the magnet arrangement direction. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a block diagram showing the configuration of an electromagnetic ultrasonic inspection device according to an embodiment of the present invention. [Figure 2] 1 is a diagram showing the structure of an electromagnetic ultrasonic probe according to an embodiment of the present invention, together with a portion of a pipe; [Figure 3]FIG. 3 is a vertical cross-sectional view taken along the line III-III in FIG. 2. [Figure 4] FIG. 4 is a vertical cross-sectional view taken along arrows IV-IV in FIG. 2. [Figure 5] 3 is an oblique cross-sectional view in the xz coordinate system of FIG. 2, showing an example of a propagation path of an ultrasonic wave in this embodiment. [Figure 6] 10A and 10B are diagrams showing data of received signals corresponding to combinations of transmitting coils and receiving coils in one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0015] An embodiment of the present invention will be described with reference to the drawings. In this embodiment, a flaw detection test of a pipe (more specifically, a weld extending in the circumferential direction of the pipe, for example) will be described as an example.

[0016] FIG. 1 is a block diagram showing the configuration of an electromagnetic ultrasonic inspection device according to this embodiment. FIG. 2 is a diagram showing the structure of an electromagnetic ultrasonic probe according to this embodiment, together with a portion of a pipe. FIG. 3 is a vertical cross-sectional view taken along arrows III-III in FIG. 2. FIG. 4 is a vertical cross-sectional view taken along arrows IV-IV in FIG. 2. FIG. 5 is an oblique cross-sectional view according to the xz coordinate system in FIG. 2, showing an example of an ultrasonic propagation path according to this embodiment. FIG. 6 is a diagram showing a plurality of received signals corresponding to combinations of transmitting coils and receiving coils according to this embodiment. Note that in FIGS. 2, 4, and 5, the surfaces of the pipes are actually curved, but are shown as flat surfaces for convenience.

[0017] The electromagnetic ultrasonic inspection device of this embodiment includes an electromagnetic ultrasonic probe 10 fixed around a pipe 1 (subject), a flaw detection device 20 that controls the electromagnetic ultrasonic probe 10 to record a plurality of received signals, a calculation device 30 that generates a flaw detection image based on the plurality of received signals recorded by the flaw detection device 20, a display device 40 (more specifically, for example, a display) that displays the flaw detection image generated by the calculation device 30, and an input device 50 (more specifically, for example, a keyboard or mouse) connected to the calculation device 30. The calculation device 30 has a ROM that stores a program, a CPU that executes processing according to the program, and a RAM that stores the processing results.

[0018] The electromagnetic ultrasonic probe 10 comprises a magnet array 13 having a resin cover 12 that covers a plurality of magnets 11 and most of the magnets except for the portions that face the piping 1, a plurality of coils 14A to 14D (four in this embodiment) wound around the magnet array 13, and a casing 15 that houses the magnet array 13 and the coils 14A to 14D.

[0019] The multiple magnets 11 are arranged in a row in the axial direction of the pipe 1 (in other words, in one direction along the surface of the pipe 1), and are alternately arranged so that the north pole or south pole faces outward in the radial direction of the pipe 1 (in other words, in the direction perpendicular to the surface of the pipe 1). This generates a static magnetic field (periodic magnetic field) in which the direction of the magnetic field alternates in the radial direction of the pipe 1. The pitch W (spacing) of the magnets 11 is the same as the width of the magnets 11.

[0020] Coils 14A to 14D are wound around magnet array 13 with their central axes in the circumferential direction of pipe 1 (in other words, along the surface of pipe 1 and in another direction perpendicular to the one direction) and are spaced apart from one another in the circumferential direction of pipe 1. The pitch p (spacing) of the coils is greater than the width e of the coils.

[0021] The flaw detection device 20 and the calculation device 30 of this embodiment use a technique called Full Matrix Capture (FMC) / Total Focusing Method (TFM) or Synthetic Aperture Focusing Technique (SAFT) to perform flaw detection scanning of the pipe 1 in the circumferential direction of the pipe 1 (in other words, in the direction perpendicular to the arrangement direction of the magnets 11 of the electromagnetic ultrasonic probe 10).

[0022] The flaw detector 20 selects and controls a combination of a transmitting coil and a receiving coil from among the coils 14A to 14D of the electromagnetic ultrasonic probe 10, thereby recording a plurality of receiving signals corresponding to the combination of the transmitting coil and the receiving coil. The details will be described below.

[0023] The flaw detection device 20 includes a demultiplexer 21 that selects one of the coils 14A to 14D as a transmitting coil, a pulser 22 that applies a transmitting signal (pulse signal) to the transmitting coil selected by the demultiplexer 21, a multiplexer 23 that selects one of the coils 14A to 14D as a receiving coil, a receiver 24 that acquires a receiving signal (waveform signal) of the receiving coil selected by the multiplexer 23, and a data recording unit 25 that records a plurality of receiving signals in association with information on the combination of the transmitting coil and the receiving coil. The data recording unit 25 is configured, for example, by a hard disk or a memory.

[0024] First, demultiplexer 21 selects coil 14A as the transmitting coil. Pulser 22 applies a transmission signal to coil 14A via demultiplexer 21, generating an eddy current in the surface layer of pipe 1 facing coil 14A. Then, due to the interaction between this eddy current and the magnetic field of each magnet 11, a Lorentz force is generated in the surface layer of pipe 1 facing each magnet 11, and the displacement of the surface layer of pipe 1 due to this Lorentz force generates an elementary wave. Note that in FIG. 3, the vibration direction of the elementary wave is actually perpendicular to the paper surface, but for convenience it is shown as parallel to the paper surface.

[0025] Since the directions of the magnetic fields generated by adjacent magnets 11 are reversed by 180 degrees, the phases of adjacent elementary waves are also shifted by 180 degrees. The elementary waves generated on the surface of the pipe 1 where the coil 14A faces (in other words, where the multiple magnets 11 face each other) are in phase with each other in the direction of the transmission angle θ expressed by the following equation (1), and therefore form a composite wave (more specifically, an SH wave; hereinafter, simply referred to as ultrasonic waves) with a transmission angle θ. In the equation, λ is the wavelength of the ultrasonic waves, V is the speed of sound, and f is the frequency of the ultrasonic waves. As is clear from equation (1), the transmission angle θ of the ultrasonic waves can be set by the frequency f of the ultrasonic waves (i.e., the frequency of the transmission signal applied to the coil 14A). For example, if the frequency of the ultrasonic waves is set to f = V / W, the transmission angle θ of the ultrasonic waves becomes 30°.

[0026]

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[0027] Multiplexer 23 sequentially selects coils 14A to 14D as receiving coils. Coil 14A as a receiving coil generates a received signal from ultrasonic waves that propagate from the surface of pipe 1 facing coil 14A as a transmitting coil, are reflected by defect 2 inside pipe 1, and return to the surface of pipe 1 facing coil 14A as a receiving coil. Coil 14B as a receiving coil generates a received signal from ultrasonic waves that propagate from the surface of pipe 1 facing coil 14A as a transmitting coil, are reflected by defect 2 inside pipe 1, and return to the surface of pipe 1 facing coil 14B as a receiving coil. Coil 14C as a receiving coil generates a received signal from ultrasonic waves that propagate from the surface of pipe 1 facing coil 14A as a transmitting coil, are reflected by defect 2 inside pipe 1, and return to the surface of pipe 1 facing coil 14C as a receiving coil (see FIG. 5). Coil 14D as a receiving coil generates a receiving signal by ultrasonic waves that are propagated from the surface of the pipe 1 facing coil 14A as a transmitting coil, reflected by a defect 2 inside the pipe 1, and returned to the surface of the pipe 1 facing coil 14D as a receiving coil.

[0028] The receiver 24 receives a signal W received by the coil 14A when the coil 14A is selected as the transmitting coil. 11 , the received signal W of the coil 14B 12 , the received signal W of the coil 14C 13 , and the received signal W of the coil 14D 14 is acquired via the multiplexer 23 and output to the data recording unit 25.

[0029] Next, demultiplexer 21 selects coil 14B as the transmitting coil. Pulser 22 applies a transmitting signal to coil 14B via demultiplexer 21, generating an ultrasonic wave in the surface layer of pipe 1 that coil 14B faces.

[0030] Multiplexer 23 sequentially selects coils 14A to 14D as receiving coils. Coil 14A as a receiving coil generates a received signal from ultrasonic waves that propagate from the surface of pipe 1 opposite coil 14B as a transmitting coil, are reflected by defect 2 inside pipe 1, and return to the surface of pipe 1 opposite coil 14A as a receiving coil. Coil 14B as a receiving coil generates a received signal from ultrasonic waves that propagate from the surface of pipe 1 opposite coil 14B as a transmitting coil, are reflected by defect 2 inside pipe 1, and return to the surface of pipe 1 opposite coil 14B as a receiving coil. Coil 14C as a receiving coil generates a received signal from ultrasonic waves that propagate from the surface of pipe 1 opposite coil 14B as a transmitting coil, are reflected by defect 2 inside pipe 1, and return to the surface of pipe 1 opposite coil 14C as a receiving coil. Coil 14D as a receiving coil generates a receiving signal by ultrasonic waves that are propagated from the surface of the pipe 1 facing coil 14B as a transmitting coil, reflected by a defect 2 inside the pipe 1, and returned to the surface of the pipe 1 facing coil 14D as a receiving coil.

[0031] The receiver 24 receives the signal W received by the coil 14A when the coil 14B is selected as the transmitting coil. 21 , the received signal W of the coil 14B22 , the received signal W of the coil 14C 23 , and the received signal W of the coil 14D 24 is acquired via the multiplexer 23 and output to the data recording unit 25.

[0032] Next, demultiplexer 21 selects coil 14C as the transmitting coil. Pulser 22 applies a transmitting signal to coil 14C via demultiplexer 21, generating an ultrasonic wave in the surface layer of pipe 1 that coil 14C faces.

[0033] Multiplexer 23 sequentially selects coils 14A to 14D as receiving coils. Coil 14A as a receiving coil generates a received signal from ultrasonic waves that propagate from the surface of pipe 1 opposite coil 14C as a transmitting coil, are reflected by defect 2 inside pipe 1, and return to the surface of pipe 1 opposite coil 14A as a receiving coil. Coil 14B as a receiving coil generates a received signal from ultrasonic waves that propagate from the surface of pipe 1 opposite coil 14C as a transmitting coil, are reflected by defect 2 inside pipe 1, and return to the surface of pipe 1 opposite coil 14B as a receiving coil. Coil 14C as a receiving coil generates a received signal from ultrasonic waves that propagate from the surface of pipe 1 opposite coil 14C as a transmitting coil, are reflected by defect 2 inside pipe 1, and return to the surface of pipe 1 opposite coil 14C as a receiving coil. Coil 14D as a receiving coil generates a receiving signal by ultrasonic waves that are propagated from the surface of the pipe 1 facing coil 14C as a transmitting coil, reflected by a defect 2 inside the pipe 1, and returned to the surface of the pipe 1 facing coil 14D as a receiving coil.

[0034] The receiver 24 receives the signal W received by the coil 14A when the coil 14C is selected as the transmitting coil. 31 , the received signal W of the coil 14B 32 , the received signal W of the coil 14C 33 , and the received signal W of the coil 14D 34 is acquired via the multiplexer 23 and output to the data recording unit 25.

[0035] Next, the demultiplexer 21 selects the coil 14D as the transmitting coil. The pulser 22 applies a transmitting signal to the coil 14D via the demultiplexer 21, thereby generating an ultrasonic wave in the surface layer of the pipe 1 that the coil 14D faces.

[0036] Multiplexer 23 sequentially selects coils 14A to 14D as receiving coils. Coil 14A as a receiving coil generates a received signal from ultrasonic waves that propagate from the surface of pipe 1 opposite coil 14D as a transmitting coil, are reflected by defect 2 inside pipe 1, and return to the surface of pipe 1 opposite coil 14A as a receiving coil. Coil 14B as a receiving coil generates a received signal from ultrasonic waves that propagate from the surface of pipe 1 opposite coil 14D as a transmitting coil, are reflected by defect 2 inside pipe 1, and return to the surface of pipe 1 opposite coil 14B as a receiving coil. Coil 14C as a receiving coil generates a received signal from ultrasonic waves that propagate from the surface of pipe 1 opposite coil 14D as a transmitting coil, are reflected by defect 2 inside pipe 1, and return to the surface of pipe 1 opposite coil 14C as a receiving coil. Coil 14D as a receiving coil generates a receiving signal by ultrasonic waves that are propagated from the surface of the pipe 1 facing coil 14D as a transmitting coil, reflected by a defect 2 inside the pipe 1, and returned to the surface of the pipe 1 facing coil 14D as a receiving coil.

[0037] The receiver 24 receives the signal W received by the coil 14A when the coil 14D is selected as the transmitting coil. 41 , the received signal W of the coil 14B 42 , the received signal W of the coil 14C 43 , and the received signal W of the coil 14D 44 is acquired via the multiplexer 23 and output to the data recording unit 25.

[0038] The data recording unit 25 records the above-mentioned received signals together with information on the combination of the corresponding transmitting coil and receiving coil. However, the combination of the transmitting coil and receiving coil may be changed as necessary, for example, when it is desired to limit the examination area or when there is a defective coil.

[0039] The calculation device 30 extracts and sums the intensities (amplitudes) of multiple received signals corresponding to each position inside the pipe 1, based on the propagation time of the ultrasonic waves corresponding to the combination of the transmitting coil and the receiving coil when it is assumed that the ultrasonic waves are reflected at that position, and generates a flaw detection image showing the distribution of the summed intensities. The details will be described below.

[0040] For example, assuming that defect 2 exists at position (xi, zi) inside pipe 1 as shown in Figure 5, ultrasonic waves generated on the surface of pipe 1 facing the transmitting coil propagate along propagation path F1, and the ultrasonic waves reflected by defect 2 propagate along propagation path F2, returning to the surface of pipe 1 facing the receiving coil. If the position of the surface of pipe 1 facing the transmitting coil is (xm, zm), the propagation time τmi of the ultrasonic waves on propagation path F1 is given by the following equation (2). Also, if the position of the surface of pipe 1 facing the receiving coil is (xn, zn), the propagation time τni of the ultrasonic waves on propagation path F2 is given by the following equation (3). Therefore, the propagation time of ultrasonic waves on propagation path (F1+F2) is given by (τmi+τni).

[0041]

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[0042]

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[0043]

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[0044] The calculation device 30 calculates, for each position (xi, zi) inside the pipe 1, the intensities W of the multiple received signals corresponding to the position (xi, zi) based on the propagation time (τmi+τni) of the ultrasonic waves corresponding to the combination of the transmitting coil and the receiving coil. nm (τmi+τni) are extracted and summed. That is, the intensity (summed value) Si corresponding to the position (xi, zi) inside the pipe 1 is calculated using the above formula (4) (however, in this embodiment, N=4). Then, the intensity Si is converted into pixel values ​​to generate a flaw detection image showing the distribution of the intensity Si. The calculation device 30 outputs the generated flaw detection image to the display device 40 for display.

[0045] As described above, in this embodiment, flaw detection scanning of the pipe 1 can be performed in the circumferential direction of the pipe 1 (in other words, in the direction perpendicular to the arrangement direction of the magnets 11 of the electromagnetic ultrasonic probe 10). Therefore, even if the position of the electromagnetic ultrasonic probe 10 is fixed, inspection can be performed over a wide range. Furthermore, when multiple electromagnetic ultrasonic probes 10 are arranged in the circumferential direction of the pipe 1, the intervals between them can be increased.

[0046] It is preferable that the pitch p of the coils of the electromagnetic acoustic probe 10 satisfies the condition of the following formula (5). σ in the formula is the representative deflection angle of the ultrasonic waves in the xz coordinate system (see FIG. 5). This makes it possible to suppress artifacts due to so-called grating lobes.

[0047]

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[0048] Furthermore, the flaw detection device 20 of this embodiment includes a demultiplexer 21 that selectively connects the coils 14A to 14D of the probe 10 to a pulser 22, and a multiplexer 23 that selectively connects the coils 14A to 14D of the probe 10 to a receiver 24. Therefore, the flaw detection device 20 can be made smaller and more cost-effective than when the demultiplexer 21 is not provided and multiple pulsers are provided that are connected to the coils 14A to 14D, respectively, or when the multiplexer 23 is not provided and multiple receivers are provided that are connected to the coils 14A to 14D, respectively.

[0049] Although not specifically described in the above embodiment, the flaw detector 20 may vary the frequency of the transmission signal applied to the transmission coil to vary the transmission angle θ of the ultrasonic waves. That is, flaw detection scanning of the pipe 1 may be performed in the axial direction of the pipe 1 (in other words, the arrangement direction of the magnets 11).

[0050] Furthermore, in the above embodiment, the calculation device 30 has been described as outputting the flaw detection image to the display device 40 for display, but this is not limited to this. For example, the image may be output to a printer for printing, or may be output to a storage medium for storage.

[0051] In the above embodiment, the electromagnetic ultrasonic probe 10 is described as having four coils 14A to 14D, but this is not limiting. The electromagnetic ultrasonic probe 10 may have two, three, or five or more coils. Regardless of the number of coils, it is possible to maintain the distance between the coils and the surface of the pipe 1, and therefore it is possible to maintain sensitivity.

[0052] Furthermore, in the above embodiment, the case where the multiple magnets 11 are arranged in a row in the axial direction of the pipe 1 has been described as an example, but this is not limiting and the magnets 11 may be arranged in multiple rows in the axial direction of the pipe 1. Furthermore, in the above embodiment, the test object is described as being the pipe 1 as an example, but this is not limiting and the test object may be, for example, a flat plate. [Explanation of symbols]

[0053] 1 Piping (test object) 10 Electromagnetic ultrasound probe 11 Magnet 13 Magnet array 14A~14D Coil 20 Flaw detection equipment 30 Computing equipment

Claims

1. an electromagnetic ultrasonic probe including: a magnet array having a plurality of magnets arranged in one direction along the surface of the subject, and arranged alternately so that one side of the direction perpendicular to the surface of the subject is a north pole or a south pole; and a plurality of coils wound around the magnet array with a central axis in another direction along the surface of the subject and perpendicular to the one direction, and spaced apart from each other in the other direction; a flaw detection device that selects a combination of a transmitter coil and a receiver coil from the plurality of coils, and records a plurality of reception signals corresponding to the combination of the transmitter coil and the receiver coil; An electromagnetic ultrasonic inspection device comprising:

2. An electromagnetic ultrasonic probe comprising: a magnet array having a plurality of magnets arranged in one direction along the surface of the subject, and arranged alternately so that one side of the direction perpendicular to the surface of the subject is a north pole or a south pole; and a plurality of coils wound around the magnet array with a central axis in another direction along the surface of the subject and perpendicular to the one direction, and spaced apart from each other in the other direction; a flaw detection device including a demultiplexer that selects one of the plurality of coils as a transmitting coil, a pulser that applies a transmitting signal to the transmitting coil selected by the demultiplexer, a multiplexer that selects one of the plurality of coils as a receiving coil, and a receiver that acquires a receiving signal from the receiving coil selected by the multiplexer; An electromagnetic ultrasonic inspection device comprising:

3. 3. The electromagnetic ultrasonic inspection device according to claim 2, The flaw detection device includes a data recording unit that records a plurality of reception signals in association with information on a combination of the transmission coil and the reception coil, The electromagnetic ultrasonic inspection device further comprises:

4. The electromagnetic ultrasonic inspection device according to claim 1 or 3, a calculation device that extracts and sums the intensities of the plurality of reception signals corresponding to each position inside the subject based on the propagation time of the ultrasound corresponding to the combination of the transmission coil and the reception coil when it is assumed that the ultrasound is reflected at the position; The electromagnetic ultrasonic inspection device further comprises:

5. 5. The electromagnetic ultrasonic inspection device according to claim 4, The computing device generates a flaw detection image showing the distribution of the combined intensities. An electromagnetic ultrasonic inspection device characterized by:

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