An inspection device and inspection method for inserted fillet welds of thick-walled pressure-bearing equipment

Abstract

The present invention discloses a detection method and a detection device for the fillet weld of an inserted nozzle of a thick-wall pressure-bearing device, which are applicable to the non-destructive testing technology field of pressure-bearing devices. The detection device includes a transmitting phased array probe, a receiving phased array probe, a wedge block group, an ultrasonic detector and a manual scanning frame. The detection method based on this detection device can detect various types of defects of the nozzle fillet weld, especially area-type defects such as transverse cracks. For the detection method of the inserted nozzle fillet weld, the detection device is placed inside the nozzle for circumferential scanning. The transmitting and receiving dual phased array probes reduce the detection blind area by transmitting and receiving ultrasonic signals, improve the signal-to-noise ratio through electronic scanning technology, and solve the detection problem of transverse cracks through TOFD technology.

Description

Technical Field

[0001] The present invention relates to the technical field of nondestructive testing of pressure-bearing equipment, and particularly relates to a detection device and a detection method for an inserted fillet weld of a thick-walled pressure-bearing equipment.

Background Art

[0002] The cylinder body and the nozzle of important thick-walled pressure-bearing equipment such as power station boilers usually adopt an inserted structure. This inserted structure bears welding stress, structural stress, shear force, and thermal stress generated by high-temperature fluctuations. Once a defect occurs, it may lead to equipment failure.

[0003] Defects of this inserted structure are usually detected by ultrasonic testing. Conventional ultrasonic testing techniques generally use one or a combination of the following methods for detection. The methods include: using a straight probe to detect on the inner wall of the nozzle; using an inclined probe to detect on the outer wall of the container by using the first and second waves; using an inclined probe to detect on the inner wall of the nozzle by using the first wave. However, conventional ultrasonic testing techniques have problems such as difficulty in distinguishing interference waves from defect waves, great difficulty in identifying defect signals, difficult defect positioning due to the curvature change of the reflection point, and missed detection of some welds. Ultrasonic phased array testing can control the focusing and deflection of the sound beam to achieve multi-dimensional display of the detection results. According to the structural form of the inserted nozzle fillet weld, one or several of the following methods are selected for combined detection. The methods are as follows: line scanning is adopted on the inner wall of the nozzle; sector scanning is adopted on the outer wall or the inner wall of the container; sector scanning is adopted on the inner wall of the container. However, the above ultrasonic phased array testing methods have low reliability in detecting transverse cracks in welds. In relevant standards and textbooks, ultrasonic phased array testing of transverse cracks in welds usually adopts oblique parallel scanning along the weld or parallel scanning after grinding the weld reinforcement flat. However, for transverse cracks in the inserted nozzle fillet weld of thick-walled pressure-bearing equipment, ultrasonic phased array testing has the following problems: 1) The wall thickness is relatively thick, while the diameter of the nozzle is usually small. When the sound beam reaches a certain sound path during oblique parallel scanning along the weld or parallel scanning after grinding the weld reinforcement flat, it has deviated from the circular weld; 2) The height of the inserted nozzle fillet weld of thick-walled pressure-bearing equipment is usually included in a part of the strength calculation, and its fillet weld height is relatively large, and it is very difficult to grind the reinforcement flat. Therefore, existing detection standards and processes are difficult to effectively perform ultrasonic testing on transverse cracks in the inserted nozzle fillet weld of thick-walled pressure-bearing equipment.

Summary of the Invention

[0004] The purpose of the present invention is to overcome the above-mentioned deficiencies of the prior art and provide a detection device and a detection method for an inserted fillet weld of a thick-walled pressure-bearing equipment.

[0005] To achieve the above object, the present invention provides a detection device for an inserted fillet weld of a thick-walled pressure-bearing device, comprising a transmitting phased array probe, a receiving phased array probe, a wedge block group, an ultrasonic detector, and a manual scanning frame for positioning. The transmitting phased array probe and the receiving phased array probe have the same specifications and are symmetrically installed above the wedge block group; the manual scanning frame is adsorbed on the inner wall of the nozzle and comprises a main frame, a probe mounting frame, magnetic rollers, and an encoder.

[0006] Preferably, it can be used to detect the inserted fillet weld formed by the cylinder body and the nozzle of the thick-walled pressure-bearing device.

[0007] Preferably, the wedge block group consists of two wedge blocks symmetrically installed on the probe mounting frame.

[0008] Preferably, the bottom surface of the wedge block is an outwardly convex arc surface that fits the inner wall of the nozzle.

[0009] Preferably, the probe mounting frame is installed at the front end of the main frame, and the probe mounting frames are symmetrically distributed about the axis of symmetry of the main frame.

[0010] Preferably, the magnetic rollers are evenly distributed on both sides of the main frame.

[0011] Preferably, the ultrasonic detector integrates TOFD and phased array functions and is connected to the transmitting phased array probe and the receiving phased array probe through probe cables.

[0012] The present invention also provides a detection method for an inserted fillet weld of a thick-walled pressure-bearing device, which uses the above detection device and comprises the following steps:

[0013] S1. Remove the sundries from the inner wall scanning area of the nozzle and place the coupling agent.

[0014] S2. Arrange the detection device on the inner wall of the nozzle, with the transmitting phased array probe and the receiving phased array probe placed above the inserted fillet weld.

[0015] S3. Turn on the ultrasonic detector. Through the transmitting phased array probe and the receiving phased array probe with the designed wafer angles and positions, the receiving phased array probe receives the sound beam of the transmitting phased array probe in the circumferential direction of the nozzle, and the semi-diffusion angle covers the width of the fillet weld.

[0016] S4. In the axial direction of the nozzle at any scanning point, the transmitting phased array probe and the receiving phased array probe perform an electronic line scan and an electronic fan scan with equal-depth focusing in the axial direction of the nozzle according to the same focusing rule, and corresponding transmitting and receiving sound beams are formed at the same focusing point.

[0017] S5. Manually rotate the manual scanning frame to make the transmitting phased array probe and the receiving phased array probe scan along the circumferential clockwise / counterclockwise direction with the wedge block group; realize the detection and defect positioning in the axial direction of the nozzle through electronic scanning, realize the detection and defect positioning in the radial direction of the nozzle through TOFD detection, and realize the detection and defect positioning in the circumferential direction through the encoder, and finally realize C-scan and 3D real-time imaging.

[0018] Preferably, the formula for the deflection angle δ of the wafer through the inner or outer boundary of the sound field is:

[0019]

[0020] The formula for the half-diffusion angle of the wafer is:

[0021]

[0022] The formula for the central position of the wafer in the width direction of the probe is:

[0023]

[0024]

[0025] In the formula, δ is the deflection angle of the wafer, β is the refraction angle of the inner or outer diffusion boundary of the ultrasonic wave on the workpiece to be inspected (β1 is the inner boundary, β2 is the outer boundary), r is the radius of the inner surface of the nozzle, l is the range of the heat-affected zone, e - 5 ≤ l ≤ e + d + 5, e is the wall thickness of the nozzle, C L1 is the longitudinal wave sound velocity of the wedge block, C L2 is the longitudinal wave sound velocity of the workpiece to be inspected, θ is the half-diffusion angle in the wedge block, d is the width of the weld, λ is the wavelength of the ultrasonic wave, f is the frequency of the acoustic wave emitted by the wafer, b is half of the width of the wafer, (x O1 , y O1 ) is the central position O1 of the transmitting wafer.

[0026] Compared with the prior art, the beneficial effects of a detection device and a detection method for an inserted fillet weld of a thick-walled pressure-bearing device provided by the present invention are as follows:

[0027] 1. The present invention adopts phased array focusing technology, and performs electronic line scanning and electronic sector scanning through electronic scanning technology in the axial direction of the nozzle. The scanning sound beam covers the entire weld thickness, and the concentrated sound energy improves the signal-to-noise ratio; the one-transmitter-one-receiver dual-probe technology is adopted to reduce the detection blind area, and longitudinal cracks, lack of penetration, lack of fusion, and volumetric defects such as pores and slag inclusions can be detected.

[0028] 2. The present invention adopts the TOFD technology. The sound beam only needs to cover the heat affected zone of the fillet weld, the sound field energy is more concentrated, the detection sensitivity is higher, and the direct wave and bottom reflection wave are effectively removed, solving the detection problem of area-type defects such as transverse cracks in fillet welds.

[0029] 3. The present invention combines the phased array detection results, TOFD detection results and encoder to achieve more accurate positioning and quantification of defects. Through the phased array detection results, the positioning of defects in the weld thickness direction and the quantification of defect height are achieved; through the TOFD detection results, the positioning of defects along the weld width direction and the quantification of defect length are achieved; through the encoder of the manual scanning frame, the defect conditions in the circumferential direction are dynamically presented, and the positioning of defects in the circumferential direction and the quantification of defect width are achieved.

[0030] 4. The present invention adopts a split wedge block group. On the basis of realizing multiple functions such as curved surface matching, sound beam coverage and dual-probe detection, the two independent wedge blocks in the wedge block group are separately assembled with the phased array probe, which is convenient for replacement after the wedge block is worn, and adjusting the wedge block curvature can adapt to different inner diameters of the nozzle and the range of the heat affected zone of the nozzle fillet weld.

[0031] The features and advantages of the present invention will be described in detail through embodiments in conjunction with the drawings.

Description of the Drawings

[0032] Figure 1 It is a schematic structural diagram of a detection device for an inserted fillet weld of a thick-walled pressure-bearing device according to an embodiment of the present invention.

[0033] Figure 2 It is a schematic structural diagram of a transmitting phased array probe, a receiving phased array probe and a wedge block group according to an embodiment of the present invention.

[0034] Figure 3 It is a schematic diagram of the sound field structure of a phased array and TOFD probe device in the present invention.

[0035] Figure 4 It is a partially enlarged schematic diagram of the sound field structure of a phased array and TOFD probe device in the present invention.

[0036] Figure 5 It is a three-dimensional schematic diagram of line scanning in the present invention.

[0037] Figure 6 It is a two-dimensional schematic diagram of line scanning in the present invention.

[0038] Figure 7 It is a three-dimensional schematic diagram of sector scanning in the present invention.

[0039] Figure 8 It is a two-dimensional schematic diagram of sector scanning in the present invention

[0040] Figure 9This is a schematic diagram of defect detection and detection results according to the TOFD principle in the present invention.

[0041] In the figure: 1. Nozzle; 2. Magnetic roller; 3. Probe mounting bracket; 4. Inserted fillet weld; 5. Cylinder; 6. Transmitting phased array probe; 7. Wedge block group; 8. Receiving phased array probe; 9. Encoder; 10. Main frame; 11. Ultrasonic detector.

Specific implementation manner

[0042] To make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the drawings and embodiments. However, it should be understood that the specific embodiments described herein are only used to explain the present invention and do not limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessarily confusing the concepts of the present invention.

[0043] In the description of the present invention, it should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0044] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present invention is usually placed during use. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more, unless otherwise specifically defined. "Several" means one or more, unless otherwise specifically defined.

[0045] In the description of the present invention, it should also be noted that, unless otherwise clearly specified and defined, the terms "arranged", "installed", "connected", and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium, and it may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0046] Referring to Figure 1 , an embodiment of the present invention provides a detection device for an inserted fillet weld of a thick-walled pressure-bearing device, including a transmitting phased array probe 6, a receiving phased array probe 8, an ultrasonic detector 11, a wedge block group 7, and a manual scanning frame for positioning. The transmitting phased array probe 6 and the receiving phased array probe 8 have the same specifications and are symmetrically installed above the wedge block group 7 to achieve dual-probe detection. The manual scanning frame is adsorbed on the inner wall of the nozzle and includes a main frame 10, a probe mounting frame 3, magnetic rollers 2, and an encoder 9 to push the scanning of the detection device.

[0047] Referring to Figure 1 , in an optional embodiment, the detection device can be used to detect transverse cracks and other types of defects in the inserted fillet weld 4 formed by the cylinder 5 and the nozzle 1 of the thick-walled pressure-bearing device.

[0048] Referring to Figure 1 , in an optional embodiment, the probe mounting frame 3 is installed at the front end of the main frame 10 and is symmetrically distributed about the axis of symmetry of the main frame 10. The magnetic rollers 2 are strong magnetic rollers and are evenly distributed on both sides of the main frame 10 to adsorb the manual scanning frame on the inner wall of the nozzle 1. The encoder 9 is installed at the center front end of the probe mounting frame 3 and is communicatively connected to the ultrasonic detector 11 to locate the detection position.

[0049] Referring to Figure 1 and Figure 2 , in an optional embodiment, the wedge block group 7 is composed of two wedges symmetrically installed on the probe mounting frame. The bottom surface of the wedge block group 7 is an outward convex arc surface that fits the concave arc surface of the nozzle to achieve surface matching; the probe mounting surfaces of the wedge block group 7 are two symmetric surfaces, and their height, spacing, and inclination angle are determined by calculating the wafer position and deflection angle. The length of the wedge is adapted to the length of the probe, and through electronic line scanning and sector scanning techniques, it is ensured that the entire weld thickness can be covered by the scanning sound beam; the width of the wedge is adapted to the width of the probe, and the sound propagation path can be completely propagated within the wedge to achieve that the sound field can cover the entire weld width.

[0050] Referring to Figure 1, in an optional embodiment, the ultrasonic detector 11 integrates TOFD and phased array functions and is connected to the transmitting phased array probe 6 and the receiving phased array probe 8 through a probe cable.

[0051] A detection method for the inserted fillet weld of a thick-walled pressure-bearing device uses the above detection device and includes the following steps:

[0052] S1. Remove the sundries in the inner wall scanning area of the nozzle 1 and place a coupling agent.

[0053] S2. Arrange the detection device on the inner wall of the nozzle 1, and place the transmitting phased array probe 6 and the receiving phased array probe 8 above the inserted fillet weld 4.

[0054] S3. Turn on the ultrasonic detector 11. Through the transmitting phased array probe 6 and the receiving phased array probe 8 with the designed wafer angles and positions, make the receiving phased array probe 8 receive the sound beam of the transmitting phased array probe 6 in the circumferential direction of the nozzle 1, and the semi-diffusion angle covers the width of the inserted fillet weld 4.

[0055] S4. In the axial direction of the nozzle at any scanning point, the transmitting phased array probe 6 and the receiving phased array probe 8 perform an electronic line scan and an electronic fan scan with equal-depth focusing in the axial direction of the nozzle according to the same focusing rule, and form corresponding transmitting and receiving sound beams at the same focusing point.

[0056] S5. Manually rotate the manual scanning frame to make the transmitting phased array probe 6 and the receiving phased array probe 8 scan along the circumferential clockwise / counterclockwise direction with the wedge block group 7. Realize the detection and defect location in the axial direction of the nozzle 1 through electronic scanning, realize the detection and defect location in the radial direction of the nozzle 1 through TOFD detection, and realize the detection and defect location in the circumferential direction through the encoder 9, and finally realize C-scan and 3D real-time imaging.

[0057] Among them, the formula for the wafer deflection angle δ through the inner or outer boundary of the sound field is:

[0058]

[0059] The formula for the wafer semi-diffusion angle is:

[0060]

[0061] The formula for the central position of the wafer in the width direction of the probe is:

[0062]

[0063]

[0064] In the formula, δ is the deflection angle of the wafer, β is the refraction angle of the internal or external diffusion boundary of the ultrasonic wave on the workpiece to be inspected, β1 is the internal boundary, β2 is the external boundary, r is the radius of the inner surface of the nozzle, l is the range of the heat affected zone, e - 5 ≤ l ≤ e + d + 5, e is the wall thickness of the nozzle, C L1 is the longitudinal wave sound velocity of the wedge, C L2 is the longitudinal wave sound velocity of the workpiece to be inspected, θ is the half-diffusion angle in the wedge, d is the width of the weld, λ is the wavelength of the ultrasonic wave, f is the frequency of the acoustic wave emitted by the wafer, b is half of the width of the wafer, (x O1 , y O1 ) is the center position O1 of the emitting wafer.

[0065] The detection method will be specifically introduced through different attached drawings.

[0066] Referring to Figure 3 , the wafers of the transmitting phased array probe 6 are incident at a certain angle in the circumferential direction (passive aperture direction), generating a diffused longitudinal wave at a certain angle in the wedge and refracting into the workpiece. The wafers of the receiving phased array probe 8 are symmetrically arranged with the wafers of the transmitting phased array probe 6 in the circumferential direction, receiving the diffracted echo in the workpiece. To detect the transverse crack of the inserted fillet weld 4, the positions and deflection angles of the probe wafers are designed so that the sound field covers the weld to be inspected and the heat affected zone.

[0067] Figure 4 In

[0068]

[0069] , the weld to be inspected and the heat affected zone (S1 - S2) are used as the target areas for the diffusion and refraction of the longitudinal wave sound field. The inner boundary (O1P1) of the diffused sound field exactly covers the target area S1, and the outer boundary (O1P2) exactly covers the target area S2. The wafer deflection angle δ can be calculated according to the formula by the inner boundary or the outer boundary of the sound field.

[0070] In the present invention, the wafer deflection angle δ is 0°, the acoustic beam radiated by the wafer is vertically incident on the wedge, and the incident acoustic beam is deflected through the contact curved surface between the wedge and the inner surface of the nozzle. The inner boundary O1P1 and the outer boundary O1P2 of the diffused sound field are horizontally symmetric.

[0071] Calculate the half-diffusion angle of the acoustic wave radiated by the wafer in the wedge at the current frequency in the width direction of the probe. The formula is

[0072] By calculating the intersection points of the diffused sound field and the inner wall of the nozzle, the equations of the inner boundary O1P1 and the outer boundary O1P2 are obtained respectively, and the intersection point of the two equations is the center position O1 of the emitting wafer.

[0073]

[0074]

[0075] The center position O2 and deflection angle of the wafer of the receiving phased array probe 8 are horizontally symmetric with those of the wafer of the transmitting phased array probe 6. Applying the above calculation method to the position and angle calculation of the transmitting phased array probe 6 and the receiving phased array probe 8 can make the diffused sound beam cover the weld width and improve the detection sensitivity.

[0076] During detection, debris on the inner wall scanning area of the nozzle 1 should be removed and ultrasonic coupling agent should be applied. The detection device is arranged on the inner wall of the nozzle 1, and the manual scanning frame is manually pushed to make the detection device scan along the circumferential direction, including two directions: clockwise and counterclockwise. As Figure 5 and Figure 6 shown, in the axial direction of the nozzle (the direction of the active aperture) at any scanning point, the transmitting phased array probe 6 and the receiving phased array probe 8 perform electronic line scanning according to the same focusing rule, and corresponding transmitting and receiving sound beams are formed at the same focusing point. Each group of array elements in the transmitting phased array probe 6 emits ultrasonic waves that are superimposed to form a new wavefront and are focused at a specific position; when the emitted ultrasonic waves are incident on a defect, a pulse reflection signal will be generated; this reflection signal is received by the receiving phased array probe 8. Through the one-transmitting and one-receiving dual-probe technology and the focusing method, not only the blind area is reduced, but also the sound energy concentration area is utilized to improve the signal-to-noise ratio, and longitudinal cracks, lack of penetration, lack of fusion, and volumetric defects such as pores and slag inclusions can be detected. The detection signals obtained by the receiving phased array probe 8 are imaged through two ultrasonic imaging methods: 1) Synthesizing and imaging all signals according to the phased array principle; 2) Imaging the signals of one-time transmission and reception according to the TOFD principle, and taking the line scanning in the direction of the active aperture as the axial movement of the probe to replace the axial scanning of the conventional TOFD probe.

[0077] Figure 5 In , the inner wall of the nozzle 1 is flush with the inner wall of the cylinder 5 and there is a chamfer, and the focusing method of the electronic line scanning cannot completely cover the weld on the inner wall side of the cylinder 5. Therefore, electronic fan scanning is required. As Figure 7 and Figure 8 shown, in order to make the sound beam cover the weld on the inner wall side of the cylinder 5, the transmitting phased array probe 6 and the receiving phased array probe 8 simultaneously adopt electronic fan scanning with equal depth focusing in the axial direction, and corresponding transmitting and receiving sound beams are also formed at the same focusing point. The detection signals obtained by the receiving phased array probe 8 are still imaged through two ultrasonic imaging methods: phased array and TOFD. By combining the electronic line scanning and the electronic fan scanning technologies, the sound beam focusing area covers the weld thickness, and the positioning of defects in the weld thickness direction and the quantification of the defect height are realized.

[0078] The TOFD detection principle is as follows Figure 9 shown. The inner wall of the nozzle 1 is concave and the near-surface area is far from the heat-affected zone, so the sound beam does not need to cover the near surface; the side of the cylinder 5 is a non-detection area of the base material, and the sound beam does not need to cover the outer surface and the near outer surface. This method removes the reflected waves from the inner and outer surfaces, has no detection blind spots, and requires a smaller sound beam divergence angle. At the location without defects, the receiving probe will not receive reflected signals; at the location with defects (such as Figure 9 the thick black line part in), the receiving probe will receive the diffraction wave signals from the upper and lower ends of the defect, and can intuitively display the upper and lower end points of the defect in a graphical manner at the same time. The sound field coverage range is only the heat-affected zone and the TOFD imaging method, the sound field energy is more concentrated, the detection sensitivity is higher, the reflected waves from the inner and outer surfaces are effectively removed, and area-type defects such as transverse cracks can be detected.

[0079] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, or improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A detection method for inserted fillet welds of thick-walled pressure-bearing equipment, characterized in that: Inserted fillet weld inspection device for thick-walled pressure-bearing equipment, the device includes a transmitting phased array probe (6), a receiving phased array probe (8), a wedge block group (7), an ultrasonic detector (11) and a manual scanning frame for positioning; the transmitting phased array probe (6) and the receiving phased array probe (8) have the same specifications and are symmetrically installed above the wedge block group (7); the manual scanning frame is adsorbed on the inner wall of the nozzle (1), including a main frame (10), a probe mounting frame (3), magnetic rollers (2) and an encoder (9), and can be used to detect the inserted fillet weld (4) formed by the cylinder body (5) and the nozzle (1) of the thick-walled pressure-bearing equipment. The wedge block group (7) is composed of two wedges symmetrically installed on the probe mounting frame (3), and the bottom surface of the wedge is an outward convex arc surface that fits the inner wall of the nozzle (1); the method includes the following steps: S1. Remove debris from the inner wall scanning area of the nozzle (1) and place a coupling agent. S2. Arrange the inspection device on the inner wall of the nozzle (1), and place the transmitting phased array probe (6) and the receiving phased array probe (8) above the inserted fillet weld (4). S3. Turn on the ultrasonic detector (11). Through the transmitting phased array probe (6) and the receiving phased array probe (8) with the designed wafer angles and positions, make the receiving phased array probe (8) receive the sound beam of the transmitting phased array probe (6) in the circumferential direction of the nozzle (1), and the semi-diffusion angle covers the width of the inserted fillet weld (4). S4. In the axial direction of the nozzle (1) at any scanning point, the transmitting phased array probe (6) and the receiving phased array probe (8) perform an electronic line scan and an electronic fan scan with equal-depth focusing according to the same focusing rule in the axial direction of the nozzle, and form corresponding transmitting and receiving sound beams at the same focusing point. S5. Manually rotate the manual scanning frame to make the transmitting phased array probe (6) and the receiving phased array probe (8) scan along the circumferential direction in the clockwise and counterclockwise directions with the wedge block group (7); realize the detection and defect positioning in the axial direction of the nozzle (1) through electronic scanning, realize the detection and defect positioning in the radial direction of the nozzle (1) through TOFD detection, and realize the detection and defect positioning in the circumferential direction through the encoder (9), and finally realize C-scan and 3D real-time imaging; the formula for the wafer deflection angle δ through the inner or outer boundary of the sound field is: The formula for the wafer semi-diffusion angle is: The formula for the central position of the wafer in the width direction of the probe is: Wherein, δ is the deflection angle of the wafer, β is the refraction angle of the internal or external diffusion boundary of the ultrasonic wave on the workpiece to be inspected, β1 is the internal boundary, β2 is the external boundary, r is the radius of the inner surface of the nozzle, l is the range of the heat affected zone, e - 5 ≤ l ≤ e + d + 5, l1 is e - 5, l2 is e + d + 5, e is the wall thickness of the nozzle, C L1 is the longitudinal wave sound velocity of the wedge, C L2 is the longitudinal wave sound velocity of the workpiece to be inspected, θ is the half-diffusion angle in the wedge, d is the width of the weld, λ is the wavelength of the ultrasonic wave, f is the frequency of the acoustic wave emitted by the wafer, b is half of the width of the wafer, (x O1 , y O1 ) is the center position O1 of the transmitting wafer.

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