Ultrasonic inspection device, method, and program

Abstract

Provided is an ultrasonic testing technology for detecting defects with a high sensitivity over a wide area.　The ultrasonic testing device comprises: a registering unit (25) for defining and registering meshes (42m) obtained by dividing the interior of an inspection target into a lattice formation on the basis of position information in a coordinate system of an array probe; a first calculating unit (11) for calculating a first path length (21) from a vibrator to where a rear surface reflected wave is incident upon each mesh (42m), on the basis of shape information (24) of the inspection target (37); a second calculating unit (12) for calculating a second path length (22) of a diffracted wave from the mesh (42m) to each vibrator; a transforming unit (26) for transforming the first path length (21) and each second path length (22) into an ultrasonic wave propagation time (tm n), combining the same, and registering the same, linked to the corresponding mesh (42m); and an integrating unit (28) for acquiring a signal strength (Im n) corresponding to the propagation time (tm n) from a detected signal (41n), and outputting an integrated value (Gm) integrated for each corresponding mesh (42m).

Description

[Technical Field]

[0001] The present invention relates to an ultrasonic inspection technique for non-destructively inspecting internal defects occurring in structural members and welded parts. [Background technology]

[0002] Welded joints are widely used in a variety of applications, from civil engineering and architectural structures such as bridges to plant equipment such as tanks and piping, and even structural components for automobile and train bodies. Therefore, nondestructive testing for defects occurring at or near welds is an important technology from the perspective of the strength of structures or sealed vessels, maintaining this strength, and ensuring their safety. In particular, the quantitative evaluation of defects and measurement of their propagation behavior are becoming increasingly important for the soundness and lifespan prediction of structures. There is also a growing demand for highly accurate and efficient nondestructive testing for sizing defects and measuring their propagation behavior. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3456953 Summary of the Invention [Problem to be solved by the invention]

[0004] When using ultrasonic inspection equipment to nondestructively inspect the shape of defects in metal base materials or welds, one method is to transmit ultrasonic waves from a single, small, wide-directivity transducer and receive them with an equally small, single transducer. However, this technology has insufficient defect detection sensitivity, making it difficult to inspect materials or welds with high attenuation.

[0005] On the other hand, there is a method that improves detection sensitivity by converging and transmitting ultrasonic waves using an array probe with multiple transducers. However, this method has the problem that the received waveforms to be processed are enormous, so only defects that exist in the area directly hit by the ultrasonic waves can be detected, leaving areas where defects cannot be detected.

[0006] The embodiments of the present invention have been made in consideration of the above circumstances, and have an object to provide an ultrasonic inspection technique that can detect defects over a wide area with high sensitivity. [Means for solving the problem]

[0007] an ultrasonic inspection device according to an embodiment, the device comprising: a setting unit that sets the incident direction and focal length of an ultrasonic beam; a transmitting unit that calculates the oscillation timing of each of a plurality of transducers arranged in an array probe based on the incident direction and the focal length and transmits a pulse signal; a receiving unit that receives detection signals obtained by detecting, by each of the transducers, diffracted waves of ultrasonic waves generated by defects due to back-reflected waves of the ultrasonic beam; a registering unit that defines and registers a mesh obtained by dividing the interior of an inspection object into a lattice shape based on position information of a coordinate system of the array probe; a first calculating unit that calculates a first path length from the transducer until the back-reflected wave is incident on the mesh based on shape information of the inspection object; a second calculating unit that calculates a second path length of the diffracted wave from the mesh to each of the transducers; a converting unit that converts the first path length and each of the second path lengths into ultrasonic propagation times, combines them, and links them to the corresponding meshes to register them; an integrating unit that acquires signal strength corresponding to the propagation time from the received detection signal, and outputs an integrated value obtained by integrating the signal strength for each of the corresponding meshes; and a display unit that displays the meshes with brightness or color corresponding to each of the integrated values. [Effects of the Invention]

[0008] Embodiments of the present invention provide an ultrasonic inspection technique that detects defects over a large area with high sensitivity. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a configuration diagram of an ultrasonic inspection device according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a block diagram of a data processing unit in the ultrasonic inspection apparatus of the first embodiment. [Figure 3]3A to 3C are explanatory diagrams of an ultrasonic beam, a back-reflected wave, and a diffracted wave of ultrasonic waves in the first embodiment. [Figure 4] FIG. 3 is an explanatory diagram of a mesh defined by dividing the inside of an inspection object into a grid in the first embodiment. [Figure 5] (A) An explanatory diagram of an ultrasonic beam and back-surface reflected waves when the focal distance is set outside the back surface of an object to be inspected whose back surface is non-planar in the second embodiment, and (B) an explanatory diagram of diffracted waves generated by defects located in the mesh. [Figure 6] (A) An explanatory diagram of an ultrasonic beam and backside reflected waves in the second embodiment when the focal distance is set outside the front surface for an object to be inspected whose back surface is non-planar, and (B) an explanatory diagram of diffracted waves generated by defects located in the mesh. [Figure 7] (A) An explanatory diagram of an ultrasonic beam and a back-surface reflected wave when the focal distance is set inside the back surface and the front surface for an inspection object whose back surface is non-planar in the second embodiment, and (B) an explanatory diagram of a diffracted wave generated by a defect located in the mesh. [Figure 8] FIG. 10 is a block diagram of a data processing unit in an ultrasonic inspection apparatus according to a third embodiment. [Figure 9] (A) An explanatory diagram of an ultrasonic beam in the third embodiment, (B) an explanatory diagram of diffracted waves of ultrasonic waves generated at a defect by back-surface reflected waves, and (C) an explanatory diagram of diffracted waves generated at a defect to which the ultrasonic beam is directly incident as an incident wave. [Figure 10] FIG. 10 is a configuration diagram of an ultrasonic inspection apparatus according to a fourth embodiment of the present invention. [Figure 11] FIG. 10 is a configuration diagram of an ultrasonic inspection device according to a fifth embodiment of the present invention. [Figure 12] 3 is a flowchart illustrating steps of an ultrasonic inspection method and an algorithm of an ultrasonic inspection program according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] (First embodiment) Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Fig. 1 is a configuration diagram of an ultrasonic inspection device 10 according to the first embodiment. Fig. 2 is a block diagram of a data processing unit 20 in the ultrasonic inspection device 10 according to the first embodiment. Fig. 3 is a block diagram of an ultrasonic beam 30 according to the first embodiment. n , rear reflected wave 31 n , ultrasonic diffracted waves 32 n (321,322…32 N 4 is an explanatory diagram of a mesh 42 defined by dividing the inside of the inspection object 37 into a grid in the first embodiment. m (421,422…42 M ) is an explanatory diagram.

[0011] As shown in FIG. 1, the ultrasonic inspection device 10 emits an ultrasonic beam 30 n (301,302…30 N A setting unit 15 sets the incident direction θ (θ1, θ2) of the beam and the distance h of the focal point 39, and a plurality of transducers 35 arranged in an array probe 36 based on the incident direction θ and the focal length h. n (351,352…35 N ) and a calculation unit 16 that calculates the oscillation timing of each of the oscillators 35. n a transmitter 17 for transmitting a pulse signal 40 for oscillating each of the ultrasonic beams 30; n Back-reflected wave 31 n (311,312…31 N ) Diffraction waves of ultrasonic waves 32 generated by defects 38 n (321,322…32 N ) (Fig. 3) to the transducer 35 n (351,352…35 N ) detected signals 41 n (411,412…41 N ) and a receiving unit 18 that receives a detection signal 41 n and a display unit 19 that displays an image of the inspection result of a defect 38 in an inspection object 37.

[0012] As shown in FIG. 2 (see FIG. 4 as needed), the data processing unit 20 generates a mesh 42 that divides the inside of the inspection object 37 into a grid based on the position information of the array probe 36 in the xz coordinate system. m (421,422…42 M ) and registers it, and a registration unit 25 registers the transducer 35 based on the shape information 24 of the inspection object 37. n From Mesh 42 m Back-reflected wave 31 n a first calculation unit 11 for calculating a first path length 21 until the beam is incident; m From oscillator 35 n (351,352…35 N ) to each of the diffracted waves 32 n (321,322…32 N ) and a second calculation unit 12 for calculating the second path distance 22 of the first path distance 21 and each second path distance 22 in accordance with the propagation time t m n (t m 1,t m 2...t m N ) and combine them into the corresponding mesh 42 m and a conversion unit 26 that links to and registers the received detection signal 41. n (411,412…41 N ) to propagation time t m n (t m 1,t m 2...t m N ) corresponding to the signal strength I m n (I m 1,I m 2…I m N ) and an acquisition unit 27 that acquires the signal strength I m n The corresponding mesh 42 m Accumulated every (G m =Σ(n=1→N)I m n ) the integrated value G m (G1, G2…G M ), and an integrating unit 28 that outputs the

[0013] Returning to Figure 1, we continue the explanation. The array probe 36 has a plurality of transducers 35 arranged in a linear or matrix form. n (351,352…35 N ) and are arranged in close contact with the test object 37 via a wedge-shaped shoe 45 and an acoustic couplant (not shown), which is a liquid acoustic medium. n (351,352…35 N ) by adjusting the delay time of the oscillation timing, the ultrasonic beam 30 n (301,302…30 N The incident direction θ of the beam 30 and the distance h of the focal point 39 can be set arbitrarily.

[0014] The setting unit 15 sets an inspection method in which the array probe 36 is fixed in the XZ coordinate system of the inspection object 37, and the incident direction θ or the focal length h of the focal point 39 is scanned, and the array probe 36 is scanned in the Y-axis direction of the inspection object 37. Alternatively, the incident direction θ and the focal length h can be fixed, and an inspection method in which the array probe 36 is scanned in the XY coordinate system of the inspection object 37 can also be set.

[0015] The calculation unit 16 calculates the incident direction θ and the focal length h of the transducer 35 based on the incident direction θ and the focal length h input by the setting unit 15. n (351,352…35 N The transmitter 17 calculates the delay time of each oscillation timing of the oscillators 35 based on the delay time calculated by the calculator 16. n (351,352…35 N ) to cause oscillation.

[0016] As shown in FIG. 3, an ultrasonic beam 30 is emitted from an array probe 36. n When the light is irradiated, it is incident on the surface of the inspection object 37 through the shoe 45 and is reflected on the back surface thereof to become the back surface reflected wave 31 n Here, the ultrasonic beam 30 n The back-reflected wave 31 is directed in a direction where the reflection angle is equal to the incident angle of the n is reflective.

[0017] This back-reflected wave 31 n If there is no defect 38 in the path, the reflected wave 31 reaches the surface of the inspection object 37, where it is repeatedly reflected and attenuated. n If there is a defect 38 in the path of the beam, it will be diffracted there, and a part of it will be diffracted as a diffracted wave 32 n (321,322…32 N ) as oscillator 35 n (351,352…35 N ) and the back surface reflected wave 31 n When the light is incident on the defect 38, it is diffracted or reflected at the tip and the main body of the defect 38. n The ultrasonic waves incident on the n Here we call it.

[0018] In the receiving section 18 (FIG. 1), such diffracted waves 32 n (321,322…32 N ) is incident on the oscillator 35 n (351,352…35 N ) output detection signal 41 n (411,412…41 N ) are received by these oscillators 35 n Detection signal 41 output from n The detection signal 41 is guided to the receiving unit 18 by the switch 14. n An amplifier (not shown) that amplifies the signal and an A / D converter (not shown) that converts the analog signal into a digital signal are provided.

[0019] In the data processing unit 20 shown in FIG. 2, the processing in the registration unit 25, the first calculation unit 11, the second calculation unit 12, and the conversion unit 26 is performed in advance before the transmission unit 17 and the reception unit 18 are operated.

[0020] The registration unit 25 divides the inside of the inspection object 37 into a grid-like mesh 42. m (421,422…42 M ) (Fig. 4). These meshes 42 mThese meshes 42 form the pixels of the image displayed on the display unit 19. m In the embodiment, the position information is defined in a plane coordinate system, but may also be defined in a three-dimensional coordinate system.

[0021] The first calculation unit 11 calculates the transducer 35 based on the shape information 24 of the inspection object 37. n From Mesh 42 m Back-reflected wave 31 n 3 or 4, if the inspection object 37 is a parallel plate whose front and back surfaces are flat and parallel, the important shape information 24 is the thickness value of the inspection object 37.

[0022] The calculation of the propagation time P of the first path 21 in the conversion unit 26 is performed by the oscillator 35 n The propagation time P of the path from the center of the f , the propagation time P of the path from the focus 39 to the reflection point r , from the reflection point to mesh 42 m Propagation time P of the path to m In this case, P=P f -P r +P m These propagation times P f ,P r ,P m is calculated from the position information of the coordinate system of the array probe 36 and the propagation velocity of the ultrasonic waves.

[0023] The second calculation unit 12 calculates the mesh 42 m From oscillator 35 n (351,352…35 N ) to each of the diffracted waves 32 n (321,322…32 N ) is calculated. The propagation time Q of the second path 22 in the conversion unit 26 is calculated. n (Q1,Q2…Q N ) calculation is performed on mesh 42 m From each oscillator 35 n (351,352…35 N) is calculated from the position information of the coordinate system of the array probe 36 and the propagation velocity of the ultrasonic waves.

[0024] The converter 26 converts the first path length 21 and each of the second path lengths 22 into ultrasonic propagation times P and Q. n and then combine them to (P+Q n ), propagation time t m n (t m 1,t m 2...t m N ) These propagation times t m n (t m 1,t m 2...t m N ) is registered in the registration unit 25 as the corresponding mesh 42 m The above is the preliminary work before the array probe 36 is brought into contact with the surface of the inspection object 37 and the inspection is actually started. This preliminary work requires calculation of the first path distance 21 and each second path distance 22 for all the θ to be scanned, and the corresponding propagation time t m n is pre-registered in the registration unit 25.

[0025] After the test starts, transducer 35 n (351,352…35 N ) and the detection signal 41 received by the receiver 18 n (411,412…41 N ) is discrete data of the signal strength I sampled at a predetermined time interval. m n (t m 1,t m 2...t m N ) and the detection signal 41 n (411,412…41 N ) to the corresponding signal strength I m n (I m 1,I m 2…Im N ) to get the

[0026] The integrating unit 28 calculates the signal strength I m n The corresponding mesh 42 m Accumulated every (G m =Σ(n=1→N)I m n ) and integrated value G m (G1, G2…G M ) is output. Although detailed description will be omitted, the calculation in the integrating unit 28 reflects the incident direction θ and focal length h set in the setting unit 15 and the scanning information 46 of the array probe 36.

[0027] The display unit 19 displays the respective integrated values G m (G1, G2…G M ) with brightness or color corresponding to mesh 42 m (421,422…42 M ) is displayed. This allows the display unit 19 to detect defects 38 that may be present inside the inspection object 37 with high sensitivity over a wide area, and to image them as the inspection results.

[0028] In some cases, the acquisition unit 27 is provided with a Hilbert transformer (not shown). In this case, the display unit 19 displays the detection signal 41 that has been subjected to the Hilbert transform. n Image based on and raw detection signal 41 n By adding and synthesizing an image based on and an image based on, it is possible to display an image that has undergone envelope processing. By performing such envelope processing, a clearer image can be obtained.

[0029] (Second embodiment) Next, a second embodiment of the present invention will be described with reference to Figures 5 to 7. The configuration of the ultrasonic inspection device 10 according to the second embodiment is the same as that of the first embodiment shown in Figures 1 and 2. In the second embodiment, an object 37 to be inspected has a non-planar back surface.

[0030] For this reason, the shape information 24 (FIG. 2) has normal information for each minute area on the back surface, which is a non-planar shape. Based on this normal information, the ultrasonic beam 30 incident on the minute area on the back surface is n The back surface reflected wave 31 is directed in a direction where the reflection angle is equal to the incident angle of n Furthermore, in the second embodiment, the focal point 39 is not only set outside the rear surface of the inspection object 37, but can also be set at any position inside the rear surface and front surface, or outside the front surface.

[0031] FIG. 5A shows an ultrasonic beam 30 when a focal point 39 is set outside the back surface of an object 37 to be inspected, the back surface of which is non-flat. n and back-reflected wave 31 n FIG. 5(B) is an explanatory diagram of the mesh 42 m Diffracted wave 32 generated by defect 38 located at n FIG.

[0032] FIG. 6A shows an ultrasonic beam 30 when a focal point 39 is set outside the front surface of an object 37 to be inspected, the back surface of which is non-flat. n and back-reflected wave 31 n FIG. 6(B) is an explanatory diagram of the mesh 42 m Diffracted wave 32 generated by defect 38 located at n FIG.

[0033] FIG. 7(A) shows an ultrasonic beam 30 when a focal point 39 is set inside the back surface and the front surface of an inspection object 37 whose back surface is non-flat. n and back-reflected wave 31 n Fig. 7(B) is an explanatory diagram of the wave. m Diffracted wave 32 generated by defect 38 located at n FIG.

[0034] (Third embodiment) Next, a third embodiment of the present invention will be described with reference to Fig. 8 and Fig. 9. Fig. 8 is a block diagram of a data processing unit 20 in an ultrasonic inspection device of the third embodiment. Fig. 9(A) shows an ultrasonic beam 30 in the third embodiment. n (301,302…30N 9B is an explanatory diagram of the back surface reflected wave 31. n (311,312…31 N ) Diffraction waves of ultrasonic waves 32 generated by defects 38 n (321,322…32 N 9(C) is an explanatory diagram of the ultrasonic beam 30 n is the direct incident wave 33 n Diffracted wave 32 generated by the defect 38 incident as n (321,322…32 N 8. In addition, in FIG. 8, parts having the same configuration or function as those in FIG. 2 are designated by the same reference numerals, and duplicated explanations will be omitted.

[0035] The overall configuration of the ultrasonic inspection device of the third embodiment is the same as that of the ultrasonic inspection device 10 of the first embodiment shown in Fig. 1, but the difference is that a third calculation unit 13 is added to the data processing unit 20 (Fig. 8). n Mesh 42 from the center m Ultrasonic beam 30 n Directly incident wave 33 n The third path distance 23 is calculated by the third calculation unit 13. Since the second path distance 22 and the third path distance 23 are the same, the third calculation unit 13 and the second calculation unit 12 perform substantially the same calculation. For convenience of explanation, the third calculation unit 13 is provided separately from the second calculation unit 12, but data processing can be performed by replacing the third path distance 23 with the second path distance 22 without providing the third calculation unit 13.

[0036] Detection signal 41 detected by the receiving unit 18 in the third embodiment n (411,412…41 N ) is a back surface reflected wave 31 as in the first embodiment. n (311,312…31 N ) Diffracted wave32 n (321,322…32 N ) (FIG. 9(B)) as well as the ultrasonic beam 30 n is incident as a direct incident wave 33 and is generated by a defect 38. n (321,322…32 N) (FIG. 9(C)) is also included. The conversion unit 26b of the third embodiment has a propagation time t m n (t m 1,t m 2...t m N ) and combine them to create the corresponding mesh 42 m and register it in the registration unit 25.

[0037] The integration unit 28 then calculates the back surface reflected wave 31 n and direct incident wave 33 n Signal strength based on I m n , the corresponding mesh 42 m This causes the ultrasonic beam 30 n The above explanation is for the case where the incident direction θ is fixed, but in the case where image synthesis is performed over a wider range, the following may be performed. That is, in the setting unit 15 (FIG. 1), the ultrasonic beam 30 n The incident direction θ (θ1, θ2) is set to scan each mesh 42 m The signal strength I corresponding to m n The above is integrated.

[0038] In the third embodiment, the back surface reflected wave 31 used in the first embodiment is n In addition, the direct incident wave 33 directly incident on the defect 38 n This allows a superimposed image to be displayed, taking into consideration the above. This allows a high-resolution, fine, and clear image to be obtained, further improving the effect of detecting defects with high sensitivity. n By taking into consideration the multiple reflected waves, the above-mentioned effect can be further improved.

[0039] (Fourth embodiment) Next, a fourth embodiment of the present invention will be described with reference to Fig. 10. Fig. 10 is a configuration diagram of an ultrasonic inspection device 10 according to the fourth embodiment. In Fig. 10, parts having the same configuration or function as those in Fig. 1 are designated by the same reference numerals, and duplicated explanations will be omitted.

[0040] In the ultrasonic inspection device of the fourth embodiment, an inspection is performed using a plurality of pairs of array probes 36 (36a, 36b). Then, by operating the switch 53, the pulse signal 40 and the detection signal 41 are transmitted to only one of the array probes 36. n is sent and received.

[0041] By setting the switch 53 to the first terminal 51, the pulse signal 40 and the detection signal 41 are transmitted to one of the array probes 36a. n Then, by setting the switch 53 to the second terminal 52, the pulse signal 40 and the detection signal 41 are transmitted to the other array probe 36b. n By switching the setting of the switch 53, it is possible to further improve the effect of detecting defects over a wide area with high sensitivity.

[0042] (Fifth embodiment) Next, a fifth embodiment of the present invention will be described with reference to Fig. 11. Fig. 11 is a configuration diagram of an ultrasonic inspection device 10 according to the fifth embodiment. In Fig. 11, parts having the same configuration or function as those in Fig. 1 and Fig. 10 are designated by the same reference numerals, and duplicated explanations will be omitted.

[0043] The ultrasonic inspection device of the fifth embodiment includes a scanning means 50 that scans the surface of an inspection object 37 (37a, 37b) with an array probe 36 (36a, 36b), and a drive control unit 55 for the scanning means 50. In the fifth embodiment, of the two flat-plate-shaped inspection objects 37 (37a, 37b), a weld 34 is inspected in which the lower end of one inspection object 37b is connected to the upper surface of the other inspection object 37a.

[0044] The scanning means 50 is a self-propelled type in which a pair of array probes 36 (36a, 36b) are mounted on a support structure 54. The support structure 54 is provided with a pair of drive wheels 59a that contact the upper surface of one inspection object 37a and a driven wheel 59b that contacts the upper surface of the other inspection object 37b. Magnets 57 (57a, 57b) are provided to press the wheels 59a, 59b against the upper surfaces of the respective inspection objects 37a, 37b.

[0045] Furthermore, the support structure 54 is provided with a motor 56 that rotates and drives the drive wheels 59a, and a position detector 58 that detects position information of the moved support structure 54. A drive control unit 55 sends power and a drive signal to the motor 56, and receives a signal from the position detector 58 as position information of the array probe 36 (36a, 36b).

[0046] The position information of the array probe 36 is obtained from the setting unit 15. n The incident direction θ and the focal point 39 are sent to the data processing unit 20 as scanning information 46. Furthermore, although not shown, a supply unit is provided at the portion where the array probe 36 (36a, 36b) contacts the inspection object 37 (37a, 37b) to continuously supply acoustic couplant (water), which is a liquid acoustic medium.

[0047] The steps of the ultrasonic inspection method according to the embodiment and the algorithm of the ultrasonic inspection program will be described based on the flowchart of the present invention shown in FIG. 12 (see FIGS. 1 and 2 as appropriate). First, the ultrasonic beam 30 n (301,302…30 N ) and the distance h of the focal point 39 are set (S11). As a result, the incident direction θ, the focal length h, and the scanning information 46 of the array probe 36 are set.

[0048] Also, a mesh 42 defined based on the position information of the xz coordinate system of the array probe 36 m (421,422…42 M ) is registered (S12). Then, the transducer 35 isn From Mesh 42 m Back-reflected wave 31 n The first path distance 21 until the incident light is calculated (S13). n From Mesh 42 m Ultrasonic beam 30 n Directly incident wave 33 n The third path 23 is also calculated.

[0049] Further mesh 42 m From oscillator 35 n (351,352…35 N ) to each of the diffracted waves 32 n (321,322…32 N ) are calculated (S14). Then, the first path distance 21 and each second path distance 22 are calculated based on the propagation time t m n (t m 1,t m 2...t m N ) and combine them (S15) to form the corresponding mesh 42 m (421,422…42 M ) and register it (S16).

[0050] Furthermore, if necessary, the third path 23 and each of the second path 22 may be separated by a propagation time t m n (t m 1,t m 2...t m N ) and combine them to create the corresponding mesh 42 m (421,422…42 M ) and registered. This registration information is linked to all θ (for example, θ1 to θ2 from 20° to 80° at 5° intervals) in the scanning (fan-shaped scanning) of the incident direction θ. 13 ) and focal length h, and their propagation times are pre-registered.

[0051] Next, the array probe 36 is brought into contact with the surface of the inspection object 37 and mechanically or electronically scanned (S17). n(351,352…35 N ) is emitted, and an ultrasonic beam 30 is projected from the array probe 36 onto the surface of the object 37 to be inspected. n (301,302…30 N ) is incident (S18).

[0052] Furthermore, the back-reflected wave 31 n (311,312…31 N ) Diffraction waves of ultrasonic waves 32 generated by defects 38 n (321,322…32 N ) to the transducer 35 n (351,352…35 N ) are detected (S19). n (351,352…35 N ) to detect signal 41 n (411,412…41 N ) is received (S20), and the registered propagation time t m n (t m 1,t m 2...t m N ) signal strength I m n (I m 1,I m 2…I m N ) is obtained (S21). n (331,332…33 N ) Diffraction waves of ultrasonic waves 32 generated by defects 38 n (321,322…32 N ) also vibrator 35 n (351,352…35 N ) and the registered signal strength I m n (I m 1,I m 2…I m N ) is obtained in the same way.

[0053] Next, a mesh 42 expressed in the xz coordinate system of the array probe 36 is generated as needed. m (421,422…42M ) is expanded into the XZ coordinate system of the inspection object 37 (S22). n (421,422…42 N ) the corresponding signal strength I m n (I m 1,I m 2…I m N ) is integrated into the integrated value G m (G1, G2…G M ) is output (S23). m (G1, G2…G M ) with brightness or color corresponding to mesh 42 n (421,422…42 N ) is illuminated, the inspection result of the defect 38 in the inspection object 37 is displayed as an image (S24). Then, the flow from (S18) to (S24) is repeated (S25, No, Yes, END) until the inspection is completed.

[0054] Furthermore, the embodiments can improve the inspection performance of non-destructive inspection of welds that are widely used in civil engineering and architectural structures such as bridges, plant equipment such as tanks and piping, and structural components of automobile and train bodies. In particular, the importance of quantitative evaluation of defects and measurement of their propagation behavior for predicting the soundness and lifespan of structures is increasing, and the embodiments can be applied to sizing of defects and measurement of their propagation behavior by non-destructive inspection.

[0055] According to at least one of the embodiments of the ultrasonic inspection device described above, an ultrasonic beam is focused by an array probe consisting of multiple transducers, reflected by the back surface, and then incident on a defect, and the generated diffracted waves are detected by each of the transducers, making it possible to detect defects over a wide area with high sensitivity.

[0056] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, modifications, and combinations can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, as well as the inventions described in the claims and their equivalents.

[0057] The ultrasonic inspection device described above includes a control device with a highly integrated processor such as a dedicated chip, FPGA (Field Programmable Gate Array), GPU (Graphics Processing Unit), or CPU (Central Processing Unit), a storage device such as ROM (Read Only Memory) or RAM (Random Access Memory), an external storage device such as HDD (Hard Disk Drive) or SSD (Solid State Drive), a display device such as a monitor, input devices such as a mouse and keyboard, and a communication I / F, and can be realized with a hardware configuration using a normal computer. Therefore, the components of the ultrasonic inspection device can also be realized by a computer processor and can be operated by an ultrasonic inspection program.

[0058] The ultrasound examination program may be provided by being pre-installed in a ROM or the like. Alternatively, the program may be provided by being stored in an installable or executable file format on a computer-readable storage medium such as a CD-ROM, CD-R, memory card, DVD, or flexible disk (FD).

[0059] The ultrasound inspection program according to this embodiment may be stored on a computer connected to a network such as the Internet and provided by downloading it via the network. The ultrasound inspection device may also be configured by combining separate modules that independently perform the functions of the components and are interconnected via a network or dedicated lines. [Explanation of symbols]

[0060] 10...ultrasonic inspection device, 11...first calculation unit, 12...second calculation unit, 13...third calculation unit, 14...switch, 15...setting unit, 16...calculation unit, 17...transmission unit, 18...reception unit, 19...display unit, 20...data processing unit, 21...first path length, 22...second path length, 23...third path length, 24...shape information, 25...registration unit, 26(26a, 26b)...conversion unit, 27...acquisition unit, 28...integration unit, 30 n (301,302…30 N )…ultrasonic beam, 31 n (311,312…31 N )…rear reflected wave, 32 n (321,322…32 N )...diffracted wave, 33...direct incident wave, 34...weld, 35 n (351,352…35 N )... Transducer, 36 (36a, 36b)... Array probe, 37 (37a, 37b)... Inspection object, 38... Defect, 39... Focus, 40... Pulse signal, 41 n (411,412…41 N )…detection signal, 42 m (421,422…42 M )...mesh, 45...shoe, 46...scanning information, 50...scanning means, 51...first terminal, 52...second terminal, 53...switching device, 54...support structure, 55...drive control section, 56...motor, 57 (57a, 57b)...magnet, 58...position detector, 59 (59a, 59b)...wheel, 59a...driving wheel, 59b...follower wheel, θ...incident direction, h...focal length, I m n (I m 1,I m 2…I m N )…Signal strength, G m(G1, G2…G M )…integrated value, t m n (t m 1,t m 2...t m N )…propagation time.

Claims

1. a setting unit that sets the incident direction and focal length of the ultrasonic beam; a transmitter that calculates an oscillation timing of each of a plurality of transducers arranged in the array probe based on the incident direction and the focal distance, and transmits a pulse signal; a receiving unit that receives a detection signal obtained by detecting, by each of the transducers, a diffracted wave of an ultrasonic wave generated by a defect due to a back-reflected wave of the ultrasonic beam; a registration unit that defines and registers a mesh obtained by dividing the inside of the object to be inspected into a grid based on position information of the coordinate system of the array probe; a first calculation unit that calculates a first path length from the transducer to the mesh where the back-reflected wave is incident, based on shape information of the inspection object; a second calculation unit that calculates a second path length of the diffracted wave from the mesh to each of the transducers; a conversion unit that converts the first path length and each of the second path lengths into ultrasonic propagation times, combines the combined ultrasonic propagation times, and links the combined ultrasonic propagation times to the corresponding meshes to register the combined ultrasonic propagation times; an integrating unit that acquires signal strength corresponding to the propagation time from the received detection signal and outputs an integrated value obtained by integrating the signal strength for each corresponding mesh; and a display unit that displays the mesh with brightness or color corresponding to each of the integrated values.

2. 2. The ultrasonic inspection device according to claim 1, The setting unit sets the incident direction of the ultrasonic beam to scan.

3. The ultrasonic inspection device according to claim 1 or 2, An ultrasonic inspection device, wherein the shape information includes information that the back surface of the inspection object has a non-planar shape.

4. The ultrasonic inspection device according to any one of claims 1 to 3, The array probe is placed on the front surface of the test object and the rear surface of the test object. An ultrasonic inspection device in which the focal point is set at any position outside the back surface, inside the back surface and front surface, or outside the front surface.

5. The ultrasonic inspection device according to any one of claims 1 to 4, A third calculation unit is further provided to calculate a third path length of a directly incident wave of the ultrasonic beam from the transducer to the mesh, the conversion unit converts the third path length and each of the second path lengths into the propagation time of the ultrasonic wave, combines them, and links them to the corresponding mesh to register them; the receiving unit also receives the detection signal of the diffracted wave generated by the defect in response to the directly incident wave, The integrating unit is an ultrasonic inspection device that integrates the signal strength based on the back-reflected wave and the directly incident wave for each corresponding mesh.

6. The ultrasonic inspection device according to any one of claims 1 to 5, The detection signal is subjected to Hilbert transformation and envelope processing, and the mesh is displayed.

7. The ultrasonic inspection device according to any one of claims 1 to 6, An ultrasonic inspection device comprising a switch that transmits the pulse signal to and receives the detection signal from only one of a plurality of pairs of the array probes.

8. The ultrasonic inspection device according to any one of claims 1 to 7, a scanning means for mechanically scanning the array probe over the surface of the inspection object; a drive control unit for the scanning means.

9. setting an incident direction and a focal distance of an ultrasonic beam; calculating an oscillation timing of each of a plurality of transducers arranged in the array probe based on the incident direction and the focal distance, and transmitting a pulse signal; receiving a detection signal obtained by detecting, by each of the transducers, a diffracted wave of an ultrasonic wave generated by a defect due to a back-reflected wave of the ultrasonic beam; a step of defining and registering a mesh obtained by dividing the inside of the object to be inspected into a grid based on position information of the coordinate system of the array probe; calculating a first path length from the transducer to the mesh where the back-reflected wave is incident based on shape information of the inspection target; calculating a second path length of the diffracted wave from the mesh to each of the transducers; a step of converting the first path length and each of the second path lengths into ultrasonic propagation times, combining the first path length and each of the second path lengths, and linking and registering the second path length and the second path length to the corresponding mesh; A step of acquiring a signal strength corresponding to the propagation time from the received detection signal, and outputting an integrated value obtained by integrating the signal strength for each corresponding mesh; and displaying the mesh with brightness or color corresponding to each of the integrated values.

10. On the computer, setting an incident direction and a focal distance of an ultrasonic beam; calculating an oscillation timing of each of a plurality of transducers arranged in the array probe based on the incident direction and the focal distance, and transmitting a pulse signal; a step of receiving a detection signal obtained by detecting, by each of the transducers, a diffracted wave of an ultrasonic wave generated by a defect due to a back-reflected wave of the ultrasonic beam; a step of defining and registering a mesh obtained by dividing the inside of the object to be inspected into a grid based on position information of the coordinate system of the array probe; a step of calculating a first path length from the transducer to the mesh where the back-reflected wave is incident, based on shape information of the inspection object; calculating a second path length of the diffracted wave from the mesh to each of the transducers; a step of converting the first path length and each of the second path lengths into ultrasonic propagation times, combining the first path length and each of the second path lengths, and linking and registering the second path length and the second path length to the corresponding mesh; A step of acquiring a signal strength corresponding to the propagation time from the received detection signal, and outputting an integrated value obtained by integrating the signal strength for each corresponding mesh; and a step of displaying the mesh with brightness or color corresponding to each of the integrated values.

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