JP4600335B2 - Ultrasonic inspection method and apparatus - Google Patents

Description

  The present invention transmits / receives an ultrasonic wave to / from a subject for cracks, cracks, and defects that are supposed to occur in the material of an object to be inspected (also referred to as a subject), and receives the result of the subject from the reception result. The present invention relates to the field of inspection technology for nondestructively evaluating the state.

  Describes technologies related to nondestructive inspection using ultrasound. There are two types of ultrasonic sensors: a single transducer sensor with a fixed transmission angle of ultrasonic waves and an ultrasonic array sensor with a variable transmission angle. FIG. 2 shows an outline of the configuration of the ultrasonic array sensor. The transducer 3 constituting the ultrasonic array sensor 12 (hereinafter also simply referred to as an array sensor) is electrically connected to the delay time control device 31 and the applied voltage generation device 32. The delay time control device 31 transmits a transmission signal 11 having a time difference, and the applied voltage generation device 32 generates an application signal 13 for the array sensor in accordance with the time difference of the transmission signal 11. The ultrasonic array sensor that has received the applied signal 13 controls the generation time of the spherical wave 14 of the ultrasonic wave generated from each transducer 3, and controls the superposition position of the phase of the spherical wave 14, thereby setting the transmission angle. It is variable.

  Further, depending on the method of controlling the voltage transmission time applied to each vibrator, a focused sound field can be formed. As shown in FIG. 2, the transmission time of the applied signal 13 from the delay time control device 31, that is, the delay time is controlled in a quadratic function. The spherical wave 14 transmitted from each transducer 3 generates an interference wave 15 by phase interference. By aligning the interference wave 15 with the focusing target point 16, a focused sound field can be formed and a strong sound wave can be irradiated to the defect.

  FIG. 3 describes received signal processing. The arrival time of a sound wave generated from a reflection source such as a defect to each transducer varies depending on the position. Therefore, arrival time information is extracted from the reception signal obtained by the array sensor 12 by the reception signal processing device 33. The signal generation position calculation device 34 performs reception wave combining processing in consideration of this arrival time difference. By this combining process, the echoes from the reflection source are superimposed, so that the SN ratio of the defect echo can be improved, and the reflected signal from the defect can be detected with high sensitivity.

  Next, a sizing technique for evaluating the size of a crack will be described. When sizing by using one ultrasonic sensor 17, the end echo method is generally used as shown in FIG. This is a method of obtaining the crack size H from the relationship shown in Equation 1, where S is the thickness of the subject, θ is the transmission and reception angle, C is the speed of sound, and T is the round-trip propagation time of the ultrasonic wave 18. It is.

  When sizing using two ultrasonic sensors 17, evaluation by the TOFD (Time of Flight Diffraction) method as shown in FIG. 5 is common. This is a method for obtaining the crack size H from the relationship shown in (Equation 2), and 2L is the distance between the transmission sensor and the reception sensor.

A conventional flaw detection method using one ultrasonic array sensor 12 is disclosed in, for example, Japanese Patent Application Laid-Open No. H11-11.
It is shown in paragraph No. 0005 in No. 51915. As shown in FIG. 6, the array sensor is arranged on the inspection surface, and the normal direction of the assumed crack surface and the direction of the transducer sensor in the longitudinal direction of the array sensor are orthogonal to each other. As a result, the ultrasonic beam is deflected in the depth direction, and the reception time of the reflected wave from the crack and the diffracted wave generated from the crack tip is evaluated, so that the detection of the crack and the sizing for evaluating the depth are performed. ing. At this time, one ultrasonic array sensor also serves as transmission and reception. However, if the orientation of the crack surface normal direction and the direction of the array sensor's transducer longitudinal direction cannot be perpendicular to each other because the orientation of the crack surface cannot be confirmed from the subject surface, etc. It is difficult to detect a clear echo from

  A conventional flaw detection method using two ultrasonic array sensors 12 is shown, for example, in paragraph No. 0008 in Japanese Patent No. 3609975. As shown in FIG. 7, the ultrasonic array sensor is arranged on the inspection surface with respect to the assumed crack surface, the normal direction of the assumed crack surface and the transducers of both ultrasonic array sensors. The longitudinal direction is made orthogonal. In this case, each ultrasonic array sensor plays a role of transmission and reception, respectively. However, if the orientation of the crack surface cannot be confirmed from the surface of the subject and the normal direction of the assumed crack surface and the transducer longitudinal direction of the ultrasonic array sensor cannot be arranged perpendicularly, It is difficult to detect a clear echo from a crack.

  Moreover, as shown in FIG. 8, when inspecting a portion having a curvature, it is common to use a water immersion method in which inspection is performed in an underwater environment. At this time, if the ultrasonic array sensor 12 is to be brought into contact with the subject 5, the water between the sensor and the subject serves as an acoustic lens. When the curved surface is concave, if the subject is metal, concrete, resin, or the like, the ultrasonic wave 18 is focused on a shallow portion (circle in FIG. 8) and deep due to the relationship between the sound speed of water and the subject. It is difficult to create a strong focused sound field in a part. For this reason, the inspectable range is a very narrow range. Further, when measuring the size of the crack, it is necessary to detect the deepest position. For this reason, it is common to perform an inspection using a swinging operation that moves the sensor away from the subject and rotates the direction of the sensor, but the crack generation position is evaluated by refraction of ultrasonic waves on the inspection surface. There is a drawback that it is difficult and the operation mechanism is complicated.

  In addition, as shown in FIG. 9, in a welded portion having a curvature, depending on how stress acts on the structure, it is assumed that the direction in which the crack is generated is parallel to the weld line (Z direction) or orthogonal. Is done. From the idea shown in FIG. 4 and FIG. 5, it is necessary to rotate the direction of the sensor depending on the crack generation direction. In addition, it is known that an austenitic stainless steel weld has anisotropy. The ultrasonic wave distortion and attenuation effect disturb the ultrasonic focused sound field, and the SN ratio of echo from the crack. May weaken and ultrasonic signals from cracks may not be detected.

  On the other hand, regarding the orientation of the array sensor, Japanese Patent Application Laid-Open No. 11-51915 describes that the transducers are arranged in the weld line direction and the ultrasonic waves are deflected in the weld line direction. It is possible to improve the detection of cracks. However, since the array sensor shown here is used alone, it receives echoes from defects and scattered echoes generated by crystal grains in the metal material. Since the scattered echoes are noise, the reception sensitivity and SN ratio are received. Is not suitable for sizing.

JP 11-51915 A Japanese Patent No. 3609975

  If the orientation of the crack surface cannot be confirmed from the subject surface, the orientation of the transducer of the ultrasonic array sensor is not necessarily arranged so as to be orthogonal to the direction of the ultrasonic array sensor facing the crack surface. It may not be possible to detect a clear echo from the crack. In addition, in the inspection of a part having curvature, the inspection is performed using a swinging operation in which the sensor is moved away from the subject and the direction of the ultrasonic array sensor is rotated. There is a disadvantage that becomes complicated. In addition, since the austenitic stainless steel welded portion having a curvature has anisotropy, the signal-to-noise ratio of the signal from the crack becomes weak, and an ultrasonic signal from the crack may not be detected.

  Therefore, 1) a method for detecting a clear echo from a crack when the direction of the crack surface cannot be confirmed from the surface of the subject, 2) a method for easily evaluating cracks in the inspection of a portion having curvature, 3) There has been a demand for a method for detecting a clear echo from a crack in an austenitic stainless steel weld site having a curvature.

  An object of the present invention is to make it possible to reliably evaluate a subject in an ultrasonic examination.

  A basic method for solving the problems of the present invention is to use a transmitting ultrasonic array sensor having a plurality of transducers and a receiving ultrasonic array sensor having a plurality of transducers, to within a subject. In the ultrasonic inspection method for transmitting and receiving ultrasonic waves to and measuring the position or size of a defect in the subject based on the reception result of the ultrasonic waves, the transmitting and receiving ultrasonic array sensors are The transducer longitudinal direction of each of the transmitting and receiving ultrasonic array sensors and the direction of a straight line passing through the center position of the transducer surface of each of the transmitting and receiving ultrasonic array sensors are formed on the surface of the subject. The outer product is arranged so that the direction of the outer product is perpendicular to the normal direction of the subject surface, the distance between the transmission ultrasonic array sensor and the reception ultrasonic array sensor in the straight line direction is changed, and the transmission ultrasonic Acoustic wave array sensor Electrically scanning the ultrasonic waves generated from the subject, receiving the ultrasonic waves from the subject with the ultrasonic array sensor for reception and transmitting and receiving the ultrasonic waves, based on the reception results of the ultrasonic waves, The ultrasonic inspection method is characterized in that the position or size of a defect in the subject is measured.

  Similarly, a basic apparatus for solving the problems of the present invention includes a transmitting ultrasonic array sensor having a plurality of transducers, a receiving ultrasonic array sensor having a plurality of transducers, and the transmitting ultrasonic waves. A delay time control device for controlling the transmission time of an electrical signal to the transducer of the array sensor, an applied voltage generator for transmitting electrical vibration to the transducer of the ultrasonic array sensor for transmission, and the ultrasonic array sensor for reception Ultrasound comprising information processing means for determining the position or size of a defect in the subject based on the reception result of the ultrasonic wave received from within the subject, and display means for displaying the processing result of the information processing means In the inspection apparatus, on the surface of the subject, the transducer passes through the longitudinal direction of the transducer of each of the ultrasonic array sensors for transmission and reception and the center position of the transducer surface of each of the ultrasonic array sensors for transmission and reception. The transmitting and receiving ultrasonic array sensors arranged so that the direction of the outer product formed by the direction of the crossing is perpendicular to the normal direction of the subject surface, and the transmitting and receiving ultrasonic array sensors are A sensor moving device that adjusts the interval between the transmitting and receiving ultrasonic array sensors by moving in the direction, a sensor position calculating device that measures the positions of the transmitting and receiving ultrasonic array sensors, and the transmitting and An ultrasonic inspection apparatus comprising a position of a receiving ultrasonic array sensor and means for calculating the position or size of the defect based on the reception result.

  According to the present invention, in an ultrasonic inspection method for evaluating the soundness of a subject using an ultrasonic array sensor, the soundness can be reliably evaluated regardless of the inclination direction of the crack 4.

  An ultrasonic inspection method according to an embodiment of the present invention uses a transmitting ultrasonic array sensor composed of a plurality of transducers and a receiving ultrasonic array sensor composed of a plurality of transducers, In the ultrasonic inspection method for evaluating the properties of the ultrasonic array sensor for transmission and the ultrasonic array sensor for reception on the same surface of the subject, the longitudinal direction of the transducer of the ultrasonic array sensor and the transducer of each ultrasonic array sensor Transmitting ultrasonic waves generated from the transmitting ultrasonic array sensor while moving the ultrasonic array sensor so that the direction of the outer product formed by the direction of the straight line passing through the center position of the plane is orthogonal to the normal direction of the subject , The ultrasonic wave generated by the reflection source in the subject is received by the receiving ultrasonic array sensor, the distance between the ultrasonic array sensors, the ultrasonic propagation time, and the ultrasonic transmission / reception Based on the time, it is characterized by measuring the position or size of the defect.

  An ultrasonic inspection apparatus according to an embodiment of the present invention includes a transmission ultrasonic array sensor configured by a plurality of transducers, a reception ultrasonic array sensor configured by a plurality of transducers, and a sensor for moving the array sensor. A moving device, a moving distance calculating device for measuring the position of the array sensor, a delay time control device for controlling the transmission time of an electric signal to the transducer of the ultrasonic array sensor for transmission, and an electric power to the transducer constituting the array sensor Applied voltage generator for transmitting vibration, received signal processing device for performing numerical operation processing on signals received by the ultrasonic array sensor for reception, test result display device for displaying test results, and data of each device In an ultrasonic inspection apparatus composed of an information processing apparatus that performs transmission and integration, on the same surface of a subject, the transducer longitudinal direction of the ultrasonic array sensor and each ultrasonic array The ultrasonic array sensor for transmission and the ultrasonic array sensor for reception are arranged so that the direction of the outer product formed by the direction of the straight line passing through the center position of the transducer surface of the sensor is orthogonal to the normal direction of the subject. In response to the electrical signal transmitted from the applied voltage generation device based on the transmission time controlled by the delay time control device while moving the ultrasonic array sensor installed in the sensor moving device, the transmission ultrasonic array sensor The ultrasonic wave that is generated by the scanning ultrasonic wave generated by receiving the ultrasonic wave that is generated by irradiating the reflection source in the subject by scanning the transmission ultrasonic wave to be generated. Based on the distance between the array sensors, the ultrasonic propagation time calculated from the received signal processing device, the ultrasonic transmission / reception angle, and the material sound velocity information, Constant and an ultrasonic inspection apparatus and displaying the inspection result display device results.

  Each embodiment will be specifically described below with reference to the drawings. First, an embodiment according to the entire ultrasonic inspection apparatus will be described with reference to FIG. In the embodiment of the present invention, a transmitting ultrasonic array sensor 1 (hereinafter referred to as array sensor 1) and a receiving ultrasonic array sensor 2 (hereinafter referred to as array sensor 2) are arranged on the surface of a subject, The direction of the outer product formed by the longitudinal direction of the transducers 3 of the array sensors 1 and 2 and the direction of the straight line 6 passing through the center position of the transducer surface of each of the array sensors 1 and 2 (also referred to as the facing direction of the array sensors 1 and 2). The array sensors 1 and 2 are arranged so that is perpendicular to the normal direction of the subject. The transducer surface 8 is a surface composed of the longitudinal edges of the transducer and is indicated by dotted lines in the array sensors 1 and 2. The transducer 3 constituting the array sensor has a curvature in a direction orthogonal to the direction of the outer product. The effect obtained when the vibrator is arranged as in the present invention will be described later with reference to the description of the first embodiment and FIG.

  The support column 21 and the track 22 are installed on a solid foundation so that stable flaw detection can be performed when the array sensor is moved. The stage 24 in which the wheels 23 are built can move stably on the track 22. The transmitting array sensor 1 and the receiving array sensor 2 are installed on the stage 24 via a vertical arm 25 and a horizontal arm 26 that hold the sensors. The arm has a spiral groove, and can be moved up and down by the vertical arm 25 and moved horizontally by the horizontal arm 26 by motor control, and the ultrasonic wave inspection can be performed by moving the array sensor to an arbitrary position. .

  The information control unit 27 instructs the movement target position, the scanner control unit 28 issues a movement signal for the target, and the stage 24 and the arms 25 and 26 move. The movement amounts of the stage 24 and the arms 25 and 26 are measured by the encoder 29, and the sensor position calculation device 30 can obtain the positions of the array sensors 1 and 2 based on the information. From the position information of the array sensor, the distance 2L between the transmission sensor and the reception sensor in Equation 2 described above can be calculated. The position of the array sensor is sent to the information control device 27 and stored in the inspection result storage device 34.

  Next, transmission / reception of ultrasonic waves will be described. The transducers 3 constituting the transmitting array sensor 1 and the receiving array sensor 2 are electrically connected to a delay time control device 31, an applied voltage generation device 32, a reception signal processing device 33, and a signal generation position calculation device 34. Connected. Regarding the transmission control of the ultrasonic wave, the delay time control device 31 transmits a transmission signal having a time difference in response to a command from the information control device 27, and the applied voltage generation device 32 applies the applied voltage according to the time difference of the transmission signal. 13 is generated for the array sensor. In the transmitting array sensor 1 that receives the applied voltage as the applied signal 13, the transmission angle is controlled by controlling the generation time of the ultrasonic spherical wave generated from each transducer 3 and controlling the superposition position of the phase of the spherical wave. The beam profile is variable.

In addition, the arrival time of the sound wave generated when the transmission ultrasonic wave is irradiated to the reflection source such as a defect varies depending on the position of the reflection source. Therefore, arrival time information is extracted from the reception signal obtained by the reception array sensor 2 by the reception signal processing device 33. The signal generation position calculation device 34 performs reception wave combining processing in consideration of this arrival time difference. By this processing, the ultrasonic wave propagation time T and the transmission and reception angles θ in the above-described equation 2 can be obtained. This information is sent to the information control device 27, and a received wave is generated based on the above-described equation 2 using L obtained earlier and the thickness S and material sound velocity C of the subject measured in advance. The position H and the size H of the crack 4 can be obtained. The ultrasonic propagation time T, transmission and reception angle θ, reception wave generation position, and crack size H obtained in this process are stored in the inspection result storage device 35 and confirmed by the inspection result display device 36. Can do. The inspection result display device 36 may be mounted on the information control device 27. The stage 24, arms 25 and 26, information control device 27, scanner control device 28, encoder 29, sensor position calculation device 30, delay time control device 31, applied voltage generation device 32, received signal processing device 33, signal generation position The calculation device 34, the inspection result storage device 35, and the inspection result display device 36 are connected by a transmission line 37. A device having both a delay time control function and a received signal control function may be connected instead of the delay time control device 31 and the received signal processing device 33.

  Next, individual ultrasonic flaw detection methods will be described. An explanatory view of the first embodiment of the ultrasonic inspection method according to the present invention is shown in FIG. In the present invention, the transmitting array sensor 1 and the receiving array sensor 2 are arranged on the surface of the subject, and the direction of the straight line 6 passing through the longitudinal direction of the transducer 3 of each array sensor and the center position of the transducer surface of each array sensor. The array sensors 1 and 2 are arranged so that the direction of the outer product formed by is perpendicular to the normal direction of the subject. The transducer surface 8 is a surface composed of the longitudinal edges of the transducer and is indicated by dotted lines in the array sensors 1 and 2.

  With the transducer arrangement as in the present invention, the ultrasonic beam can be scanned in the X direction. In this case, flaw detection of a crack parallel to the X direction can be performed in the same manner as in the prior art. However, as shown in FIG. 11, a focused beam is applied to the crack even for a crack inclined with respect to the X direction. I can do it. In addition, the end echo is generated at a wide angle from the crack 4, but there is a spatial distribution in the intensity of the diffracted wave. The echo becomes weak and difficult to distinguish from noise. However, since the receiving array sensor 2 can perform reception in consideration of the delay time with respect to the X direction, it is weak by performing reception wave combining processing in consideration of the arrival time difference described in the background art section. Even the partial echo can increase the reception intensity, and can achieve separation from noise and improvement of the SN ratio.

  In addition, since this method is a defect evaluation method using an end echo that is a diffracted wave from the defect, its function is impaired regardless of whether the defect opening is on the sensor arrangement side, the non-sensor arrangement side, or the hollow defect. I can't. Further, in the present invention, in order to cross the ultrasonic beams from the array sensors 1 and 2, it is effective to use an array sensor having an inclined transducer surface.

  Further, when the ultrasonic inspection is actually performed, the array sensors 1 and 2 are moved in the direction of the straight line 6 which is the facing direction, and the interval between the array sensors 1 and 2 is changed. When changing the inspection position, the array sensors 1 and 2 are moved in the same direction in the direction of the straight line 6, and when an ultrasonic wave is received from a reflection source presumed to be defective, the distance between the sensors 2L and the received wave From the ultrasonic wave propagation time T, the transmission and reception angles θ obtained by the analysis, the thickness S of the subject, and the sound velocity C of the material, the received wave generation position and the size of the crack 4 based on the above-described formula 2. The height H can be obtained.

  As an example of the first embodiment, the tandem method shown in FIG. 12 is also effective. This is because the transmitting array sensor 1 and the receiving array sensor 2 are arranged so that the angle β formed by the emission direction of each main beam of ultrasonic waves is within 90 °, and the angles of the transducer surfaces are different from each other. To do. In the tandem method, an ultrasonic beam emitted from an array sensor arranged on the side closer to the crack 4 is directly applied to the tip of the crack 4. The array sensor arranged on the side far from the crack 4 receives the diffracted wave generated by hitting the tip of the crack 4. Even in this case, if the distance 2L between the sensors, the ultrasonic wave propagation time T obtained by analyzing the received wave, the transmission and reception angles θ, the plate thickness S of the subject, and the material sound velocity C are known, Expression 2 of the description Based on the received wave generation position, the size of the crack 4 can be obtained.

  FIG. 13 shows an explanatory diagram of the second embodiment of the ultrasonic inspection method according to the present invention. In the present invention, the transmitting array sensor 1 and the receiving array sensor 2 are arranged on the surface of the subject, and the direction of the straight line 6 passing through the longitudinal direction of the transducer 3 of each array sensor and the center position of the transducer surface of each array sensor. The array sensors 1 and 2 are arranged so that the direction of the outer product formed by is perpendicular to the normal direction of the subject. The second embodiment is characterized in that the vibrator 3 has a curvature. When the vibrator 3 as shown in FIG. 10 is straight, a focused beam in the YZ direction cannot be formed. However, a vibrator having a curvature can form a focused beam on the YZ plane. Thereby, the beam intensity at the focusing point can be further increased, and the SN ratio can be improved as compared with the first embodiment.

  FIG. 14 shows an explanatory diagram of the third embodiment of the ultrasonic inspection method according to the present invention. In the present invention, the transmitting array sensor 1 and the receiving array sensor 2 are arranged on the surface of the subject, and the longitudinal direction of the transducer 3 and each transducer surface 8 of each array sensor are the edges in the longitudinal direction of the transducer. The array sensor 1 and 2 are indicated by dotted lines in the plane constituted by The array sensors 1 and 2 are arranged so that the direction of the outer product formed by the direction of the straight line 6 passing through the center position of the transducer surface of the array sensor is orthogonal to the normal direction of the subject.

  The third embodiment is characterized in that the wedge 7 that can change the ultrasonic transmission angle in the YZ direction is arranged on the transducer surface of the array sensor in the first embodiment. In general array sensors, the transducer surface is often made to be parallel to the subject surface. Even in such an array sensor, if the wedge 7 is used, the refraction angle of the ultrasonic wave can be easily changed, so that the inspection can be performed under the optimum flaw detection conditions according to the depth of the subject and the crack 4. . Further, if the wedge has a curvature in the YZ plane direction, a focusing effect in the YZ plane direction can be given, and the same effect as in the second embodiment can be obtained.

  In the second and third embodiments, when actually performing the ultrasonic inspection, the array sensors 1 and 2 are scanned before and after the facing direction. When ultrasonic waves are received from a reflection source estimated to be defective, the distance 2L between the sensors, the ultrasonic wave propagation time T obtained by analyzing the received wave, the transmission and reception angles θ, and the thickness S of the subject, From the material sound velocity C, the received wave generation position and the size H of the crack 4 can be obtained based on the above-described Expression 2. The third embodiment can also be applied to the tandem method shown in FIG. 12 shown as an example of the first embodiment described above.

FIG. 15 shows an explanatory diagram of the fourth embodiment of the ultrasonic inspection method according to the present invention. FIG. 16 shows a state in FIG. 15 which is parallel to the Z direction and parallel to the normal direction N of the subject surface. In the present invention, the transmitting array sensor 1 and the receiving array sensor 2 are arranged on the surface of the subject, and the direction of the straight line 6 passing through the longitudinal direction of the transducer 3 of each array sensor and the center position of the transducer surface of each array sensor. The array sensors 1 and 2 are arranged so that the direction of the outer product formed by is perpendicular to the normal direction of the subject surface. With such a transducer arrangement, it is possible to scan the ultrasonic beam in the direction orthogonal to the Z direction while focusing the beam.

  According to this embodiment, in the case of a crack 4 as shown in FIG. 15, the deepest position of the crack 4 can be detected by scanning with an ultrasonic beam. Therefore, a mechanism for rotating the array sensor in the direction orthogonal to the Z direction is not required, the mechanism for moving the array sensor can be reduced, and the array sensor can access narrow spaces. In addition, a curvature in the XY direction is provided on the subject contact surface of the array sensor to improve the contact property. In addition, the material of the curvature part to be brought into contact with the subject of the array sensor may be a material property such as resin, metal, etc. where the acoustic impedance is between the acoustic impedance of the subject and the acoustic impedance of the contact medium. Energy transfer efficiency can be improved compared to the water immersion method, and ultrasonic waves can be strongly incident into the subject. From the above effects, according to the present invention, it is possible to form a stronger sound field than the water immersion method described in the background art section, and to receive a weak end echo from the tip of the defect with high sensitivity. .

  Such a curvature portion can be found in a T joint, a cross joint, or the like. When the joint material has acoustic anisotropy, such as an austenitic stainless steel weld, welding is performed by scanning the welding rod in the Z direction. Here, the crystal structure of the welded portion becomes a columnar crystal that grows in the normal direction of the material surface to be heat-removed. That is, it grows in the normal direction with respect to the Z direction. That is, a uniform crystal structure is obtained in the normal direction with respect to the subject surface parallel to the Z direction. Longitudinal ultrasonic waves are likely to propagate in the 45 degree direction for such a weld having a uniform crystal structure. Therefore, for example, if the transducer surface is tilted so that the transmission / reception angle θ of the ultrasonic wave in the subject shown in FIG. .

  FIG. 17 is an explanatory diagram of the fifth embodiment of the ultrasonic inspection method according to the present invention. In the present invention, the transmitting array sensor 1 and the receiving array sensor 2 are arranged on the surface of the subject, and a straight line 6 passing through the longitudinal direction of the transducer 3 of each array sensor and the center position of the transducer surface of each ultrasonic array sensor. The array sensors 1 and 2 are arranged so that the direction of the outer product formed by the direction of is perpendicular to the normal direction of the subject. The fifth embodiment is characterized in that the vibrator 3 has a curvature. When the vibrator 3 as shown in FIG. 15 is straight, a focused beam cannot be formed on the YZ plane. However, a vibrator having a curvature can form a focused beam in the YZ direction. Thereby, the beam intensity at the focal point can be further increased, and the sensitivity can be made higher than that of the fifth embodiment.

  FIG. 18 is an explanatory diagram of the sixth embodiment of the ultrasonic inspection method according to the present invention. In the present invention, the transmitting array sensor 1 and the receiving array sensor 2 are arranged on the surface of the subject, and a straight line 6 passing through the longitudinal direction of the transducer 3 of each array sensor and the center position of the transducer surface of each ultrasonic array sensor. The array sensors 1 and 2 are arranged so that the direction of the outer product formed by the direction of is perpendicular to the normal direction of the subject surface. The sixth embodiment is characterized in that a wedge 7 whose ultrasonic transmission angle can be changed in the YZ direction is arranged on the transducer surface of the array sensor, and a curvature is provided on the contact surface of the wedge with the subject. As a result, the wedge is brought into contact with the array sensor as shown in the first embodiment or the array sensor made for the inspection of the flat plate portion as shown in the present invention, so that it is equivalent to the sixth embodiment. An effect is acquired and the existing array sensor can be diverted.

  In the fourth, fifth, and sixth embodiments, the ultrasonic sensors are actually moved by moving the array sensors 1 and 2 back and forth in the frontal direction. When ultrasonic waves are received from a reflection source estimated to be defective, the distance 2L between the sensors, the ultrasonic wave propagation time T obtained by analyzing the received wave, the transmission and reception angles θ, and the thickness S of the subject, From the material sound velocity C, the received wave generation position and the size H of the crack 4 can be obtained based on the above-described Expression 2. It is also conceivable to apply this embodiment to the tandem method.

  As is clear from the above embodiments, according to the present invention, in an ultrasonic inspection method for evaluating the soundness of a subject using an ultrasonic array sensor, a transmitting ultrasonic array sensor and a receiving ultrasonic array are used. The sensor is arranged on the surface of the subject, and the direction of the outer product (X direction) formed by the longitudinal direction of the transducer of each array sensor and the direction of the straight line passing through the center position of the transducer surface of each ultrasonic array sensor is the method of the subject. The array sensor is arranged so as to be orthogonal to the line direction. Accordingly, since the ultrasonic beam can be scanned in the X direction, the focused beam can be irradiated to the crack 4 even for the crack 4 inclined with respect to the X direction. Further, since reception signal processing in consideration of the delay time can be performed in the X direction, it is possible to increase the reception intensity of weak end echoes and secure a high S / N ratio to reliably evaluate soundness.

  The present invention is used in a nondestructive inspection method and apparatus using ultrasonic waves.

It is a block diagram of the ultrasonic inspection apparatus used with the ultrasonic inspection method of this invention. It is a conceptual diagram of the focused sound field formation method using an ultrasonic array sensor. It is a conceptual diagram of the received signal processing using an ultrasonic array sensor. It is principle explanatory drawing of the edge part echo method using an ultrasonic sensor. It is a principle explanatory view of the TOFD method using an ultrasonic sensor. It is explanatory drawing of the flaw detection method at the time of using one ultrasonic sensor. It is explanatory drawing of the flaw detection method at the time of using two ultrasonic sensors. It is explanatory drawing of the flaw detection method in a curvature site | part. It is explanatory drawing of the flaw detection method in the welding site | part which has a curvature. It is explanatory drawing of the ultrasonic inspection method of the 1st Embodiment of this invention. It is explanatory drawing regarding a crack angle when arrangement | positioning of the array sensor of the 1st Embodiment of this invention. It is another explanatory drawing of the ultrasonic inspection method of a 1st embodiment of the present invention. It is explanatory drawing of the ultrasonic inspection method of the 2nd Embodiment of this invention. It is explanatory drawing of the ultrasonic inspection method of the 3rd Embodiment of this invention. It is explanatory drawing of the ultrasonic inspection method of the 4th Embodiment of this invention. It is supplementary explanatory drawing of the ultrasonic inspection method of the 4th Embodiment of this invention. It is explanatory drawing of the ultrasonic inspection method of the 5th Embodiment of this invention. It is explanatory drawing of the ultrasonic inspection method of the 6th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Transmission ultrasonic array sensor, 2 ... Reception ultrasonic array sensor, 3 ... Vibrator, 4 ... Crack, 5 ... Subject, 6 ... Straight line, 7 ... Wedge, 8 ... Transducer surface, 11 ... Transmission Signal: 12 ... Ultrasonic array sensor, 13 ... Applied signal, 14 ... spherical wave, 15 ... interference wave, 16 ... focusing point, 17 ... ultrasonic sensor, 18 ... ultrasonic wave, 21 ... post, 22 ... orbit, 23 ... wheels, 24 ... stage, 25 ... vertical arm, 26 ... horizontal arm, 27 ... information control device, 28 ... scanner control device, 29 ... encoder, 30 ... sensor position calculation device, 31 ... delay time control device, 32 ... application Voltage generating device 33... Reception signal processing device 34... Signal generation position calculating device 35 .. inspection result storage device 36 .. inspection result display device 37.

Claims (9)

Using a transmitting ultrasonic array sensor having a plurality of transducers and a receiving ultrasonic array sensor having a plurality of transducers, ultrasonic waves are transmitted and received within the subject, and the ultrasonic waves In the ultrasonic inspection method for measuring the position or size of the defect in the subject based on the reception result,
The ultrasonic array sensors for transmission and reception are arranged on the surface of the subject with the longitudinal direction of transducers of the ultrasonic array sensors for transmission and reception and the ultrasonic array sensors for transmission and reception. Arranged so that the direction of the outer product formed by the direction of the straight line passing through the center position of the transducer surface is orthogonal to the normal direction of the subject surface,
Changing the interval in the direction of the straight line between the ultrasonic array sensor for transmission and the ultrasonic array sensor for reception, and electrically scanning the ultrasonic waves generated from the ultrasonic array sensor for transmission; From the receiving ultrasonic array sensor to receive the ultrasonic wave and transmit and receive the ultrasonic wave,
An ultrasonic inspection method for measuring a position or size of a defect in the subject based on a reception result of the ultrasonic wave.   In Claim 1, The said ultrasonic wave is transmitted in the said test object from the surface which has the curvature with which the said to-be-inspected object is equipped, It passes through the surface with the curvature with which the to-be-inspected object is provided, The said ultrasonic wave is received. Characterized ultrasonic inspection method.   3. The focused ultrasonic wave according to claim 1 or 2, wherein at least one transducer of each of the transmitting and receiving ultrasonic array sensors has a curvature in a direction orthogonal to the direction of the outer product, and is focused based on the curvature. Ultrasonic inspection method characterized by performing transmission / reception.   3. The ultrasonic wave transmission / reception method according to claim 1, wherein a wedge is disposed on at least one transducer surface of each of the transmitting and receiving ultrasonic array sensors, and the ultrasonic wave is refracted by the wedge to transmit / receive ultrasonic waves. An ultrasonic inspection method characterized by that.   3. The ultrasonic wave according to claim 2, wherein a wedge having a curved surface opposite to the curved surface is disposed on at least one transducer surface of each of the transmitting and receiving ultrasonic array sensors, and the ultrasonic wave is refracted by the wedge. Ultrasonic inspection method characterized by performing transmission / reception. A transmitting ultrasonic array sensor having a plurality of transducers, a receiving ultrasonic array sensor having a plurality of transducers, and a delay for controlling a transmission time of an electric signal to the transducers of the transmitting ultrasonic array sensor Based on a time control device, an applied voltage generator for transmitting electrical vibrations to the transducer of the ultrasonic array sensor for transmission, and a reception result of ultrasonic waves received from within the subject by the ultrasonic array sensor for reception In an ultrasonic inspection apparatus comprising information processing means for obtaining a position or size of a defect in a subject and display means for displaying a processing result of the information processing means,
On the surface of the subject, the outer product formed by the longitudinal direction of the transducer of each of the transmitting and receiving ultrasonic array sensors and the direction of the straight line passing through the center position of the transducer surface of each of the transmitting and receiving ultrasonic array sensors. Each of the ultrasonic array sensors for transmission and reception arranged in such a manner that the direction thereof is orthogonal to the normal direction of the subject surface;
A sensor moving device for adjusting the interval between the transmitting and receiving ultrasonic array sensors by moving the transmitting and receiving ultrasonic array sensors in the direction of the straight line;
A sensor position calculation device for measuring the positions of the transmitting and receiving ultrasonic array sensors;
An ultrasonic inspection apparatus comprising: positions of the transmitting and receiving ultrasonic array sensors; and means for calculating the position or size of the defect based on the reception result.   7. The ultrasonic inspection apparatus according to claim 6, wherein at least one transducer of each of the transmitting and receiving ultrasonic array sensors has a curvature in a direction orthogonal to the direction of the outer product.   The ultrasonic inspection apparatus according to claim 6, wherein a wedge is arranged on at least one transducer surface of each of the ultrasonic array sensors for transmission and reception. 7. The ultrasonic inspection according to claim 6, wherein a wedge having a curved surface facing the surface of the subject is arranged on at least one transducer surface of each of the ultrasonic array sensors for transmission and reception. apparatus.

Images