A method for measuring the width of ultrasonic angular beam in vertical cross section

Abstract

The invention relates to the technical field of ultrasonic nondestructive testing, and in particular to a method for measuring the width of an ultrasonic angular sound beam in a vertical cross section. The method comprises the following steps: Step 1: manufacturing a carbon steel test block with a length of L, a width of W, and a thickness of H, and processing an artificial reflector of a hemispherical bottom side through hole at different depths from an upper surface of the test block on the side of the end face in the length direction of the test block, wherein the diameter of the side through hole is Φ, the bottom face of the side through hole is a hemispherical surface with a diameter of Φ, the distance between the center of the hemispherical bottom circle and the end face is F, and the roughness of each inner and outer surface, the diameter tolerance of the hole and the hemisphere, the verticality of the opening and other dimensional tolerances meet certain conditions; the lateral resolution can be calculated according to the width of the angular sound beam in a vertical cross section, so as to judge the minimum detectable length of oriented defects such as unfusion, cracks, delamination, etc. perpendicular to the angle, or the accuracy of measuring the defect length using a length measurement method such as a ‑6dB method can be determined according to the width of the sound beam in a vertical cross section.

Description

Technical Field

[0001] The invention relates to the technical field of ultrasonic nondestructive testing, in particular to a method for measuring the width of an ultrasonic angular sound beam in a vertical cross section. Background Art

[0002] Ultrasonic testing technology is widely used in various industries such as special equipment, aerospace, petrochemical, shipbuilding, railways, metallurgy, machinery, etc. It is suitable for different manufacturing processes such as welding, casting, forging, etc., and can detect metal, non-metal and composite material components of various shapes such as plates, pipes, and bars. Measuring the resolution of the ultrasonic testing system is crucial for testing the performance of the ultrasonic detector and probe combination, evaluating the characteristics of the sound beam, qualitatively and quantitatively determining the defects found in the inspected workpiece, accurately measuring the geometric dimensions of the defects, and then assessing the quality grade. Whether it is conventional ultrasound, or ultrasonic testing such as phased array ultrasound, laser ultrasound, and electromagnetic ultrasound, the higher the resolution of ultrasonic testing, the easier it is to obtain the detailed characteristics of the defects, and the more accurate the quantitative and qualitative detection results of the defects. Especially in ultrasonic imaging testing, the higher the resolution of ultrasonic testing and the higher the imaging resolution, the closer it is to the true form of the defect.

[0003] The resolution of an ultrasonic testing system refers to the minimum distance between two reflectors of a certain size when it can provide separable indications. The ultrasonic testing resolution is divided into longitudinal resolution in the direction of sound wave propagation and transverse resolution perpendicular to the propagation direction. Transverse resolution is related to the beam width, which can be expressed as one-fourth of the beam width. The smaller the beam width, the higher the transverse resolution. Therefore, accurate measurement of the beam width is an effective means to evaluate the transverse resolution of the ultrasonic testing system. In various standard systems at home and abroad, for various different inspection objects, evaluating the geometric size of defects, especially the length of defects, is a common indicator for judging quality grades. It is very important to judge the minimum length of measurable defects based on the beam width (when the beam width is greater than the defect size, the beam width is measured when measuring the defect, and the defect size cannot be measured), or to judge the accuracy of measuring the defect length using length measurement methods such as the -6dB method based on the transverse resolution, and then objectively and accurately evaluate the quality grade of welds, castings, forgings or other forming process workpieces based on the acceptance criteria. In addition, accurate measurement of the sound beam width is of great significance for evaluating the sound beam coverage during the scanning process of the workpiece, so as to meet the specific requirements of different inspection standards for the sound beam coverage, achieve 100% scanning with full coverage of the sound beam, and avoid missed defects.

[0004] For workpieces such as plates and forgings that require zero-degree beam scanning and inspection, the zero-degree beam width is usually measured by placing the probe directly above the flat-bottom hole or transverse through hole, adjusting the maximum reflection amplitude to 80% of the screen height, and moving the scan left and right to reduce the maximum reflection amplitude by -6dB. The measured moving distance is the beam width. For workpieces such as welds and certain forgings that require angle beam scanning and inspection, especially when conventional ultrasonic inspection of welds using single crystal, dual crystal, longitudinal wave, and transverse wave oblique probes, especially when using phased array ultrasonic sector scanning or certain angle beam inspection, the primary wave, secondary wave, or multiple waves of certain specific angle beams can be nearly perpendicular to the interface of oriented area defects such as unfused cracks, generate higher amplitude echoes, and measure the length of the defect. Therefore, it is necessary to accurately measure the beam width of the cross section perpendicular to the angle beam, such as Figure 1 As shown in P of 101, or its lateral resolution, to evaluate the accuracy of defect length measurement.

[0005] The national standard "Reference Test Blocks and Methods for Measuring the Beam Characteristics of Contact Probes for Nondestructive Ultrasonic Testing" GB / T18852-2020 provides a method for preparing the cross-sectional beam characteristic curve of an oblique probe, which can be measured on a semicircular step (HS) test block, but what is measured is the "half" beam width, and the entire beam width cannot be directly measured. Moreover, the reflector of the semicircular step test block is an arc surface, which is equivalent to the bottom surface of a cylinder, and the echo sound pressure is the same as the large flat bottom echo sound pressure. If the beam width with -6dB as the boundary is measured, this reflector can only measure the width when the overall amplitude of the reflected echo sound pressure of the entire beam cross-section at the interface drops by -6dB. This method cannot measure the boundary when the maximum sound pressure amplitude of the angular beam axis drops by -6dB, and can only be measured roughly, and what is measured is not the true beam width.

[0006] Appendix A of the national standard "Performance and Inspection of Phased Array Ultrasonic Testing Systems for Nondestructive Testing Instruments" GB / T29302-2012 provides two methods and test blocks for measuring the beam width of the phased array probe's angular sound beam in the direction of the driven axis. One method is to use a flat-bottomed hole step test block with different depths to measure the beam width of the angular sound beam in the direction of the driven axis by transmitting echoes from the flat-bottomed hole end angles, such as Figure 2 However, the beam width measured by this method is the beam width of the angle beam projected in the direction of the driven axis from the top view of the scanning plane, that is, Figure 1 The Y in 102 is not the beam width of the angle beam in the vertical plane in the driven axis direction, and the secondary wave beam width cannot be measured.

[0007] Another method is to use a test block with an inclined through hole perpendicular to the angle sound beam, and measure the width of the sound beam in the vertical cross section in the direction of the driven axis of the angle sound beam through the cylindrical reflection of the inclined through hole, such as Figure 3 shown. Figure 1The angle θ between the mid-plane 101 (the beam width projected from the top view of the angle beam) and the plane 102 (the beam width at the vertical cross section of the angle beam) is the complementary angle of the natural exit angle of the wedge. Although the beam width measured by this method is the beam width of the vertical cross section of the angle beam in the direction of the driven axis, that is, Figure 1 As shown in P of 101, the beam width of the first wave, the second wave or the multiple waves can be measured. However, this method requires the processing of through holes with different fixed inclination angles, and can only measure the beam of a certain emission angle, and cannot continuously measure beams of different angles. For the fan-shaped scanning imaging process commonly used in weld detection, it is not convenient to use this measurement method to measure the beam width of the vertical cross section of the beam at different angles. Moreover, due to the limitations of actual processing capabilities and costs, the diameter of the through hole is difficult to reach within 2mm. If the inclination angle is large or the thickness of the test block is large, it will be more difficult to process the oblique through hole, and the minimum diameter of the through hole that can be processed will be larger. Therefore, we propose a method for measuring the beam width of the vertical cross section of an ultrasonic angle beam. Summary of the invention

[0008] The object of the present invention is to provide a method for measuring the width of an ultrasonic angle beam vertical cross-section to solve the problems raised in the above background technology.

[0009] To achieve the above object, the present invention provides the following technical solutions:

[0010] A method for measuring the vertical cross-sectional sound beam width of an ultrasonic angle sound beam, using an artificial reflector with a through hole on the bottom side of a hemisphere, and a pulse ultrasonic emission method can measure the vertical cross-sectional sound beam width of an angle sound beam with continuous different emission angles or deflection angles. Taking the ultrasonic detection process represented by phased array ultrasonic weld detection as an example, the method includes the following steps:

[0011] Step 1: Make a carbon steel test block with a length of L, a width of W, and a thickness of H, and process an artificial reflector with a through hole on the bottom of the hemisphere at different depths from the upper surface of the test block on the side of the end face in the length direction of the test block. The diameter of the side through hole is Φ, and the bottom surface of the side through hole is a hemisphere with a diameter of Φ. The distance from the center of the bottom of the hemisphere to the end face is F. The roughness of each inner and outer surface, the diameter tolerance of the hole and the hemisphere, the verticality of the opening and other dimensional tolerances meet certain conditions;

[0012] Step 2: Select a phased array probe with a certain frequency, number of array elements, and array size, install the corresponding wedge, and connect the phased array ultrasound host;

[0013] Step 3: Set the workpiece thickness, material, and workpiece type in the phased array ultrasonic detector operation interface;

[0014] Step 4: Set the focus law parameters: Set the transmission and reception mode, input the basic parameters of the probe and the basic parameters of the wedge, set the number of array elements that can be excited, the sequence number of the first array element to be excited, select the sector scanning mode, set the minimum and maximum sound beam angles of the sector scanning, the angle step, the focusing mode and the focusing depth (or distance), and finally set the step offset (the distance from the front edge of the wedge to the center line of the weld) so that the primary wave covers the middle and lower part of the weld and the heat-affected zone, and the secondary wave covers the middle and upper part of the weld and the heat-affected zone, so as to ensure full coverage of the weld inspection area, thereby generating the focus law;

[0015] Step 5: Calibration: perform sound velocity calibration, then wedge delay calibration, then TCG calibration (including ACG calibration), and finally select the encoder and perform encoder calibration;

[0016] Step 6: Set the ultrasonic parameters; mainly set the starting depth and depth range of the display, display the weld detection area, and adjust the display gain;

[0017] Step 7: Set scanning parameters: mainly set the scanning starting 0 point position, scanning area range, pulse repetition frequency, maximum scanning speed, scanning step, encoder polarity;

[0018] Step 8: After applying coupling agent on the test block, scan the artificial reflector of the through hole on the bottom side of the hemisphere, collect the test data, and use the saved data to measure the sound beam width using offline analysis software.

[0019] As a preferred solution of the present invention, the length of the test block made in the step one can at least meet the coverage of the secondary wave sound path on the artificial reflector, the width of the test block can meet the scanning of the artificial reflector by the wedge block in the direction of the driven axis, and hemispherical bottom side through holes are provided on both end faces in the length direction of the test block. The diameter of the side through holes and the diameter of the hemispherical bottom surface should be smaller while meeting the processing tolerance conditions, and the roughness of each inner and outer surface should be smaller.

[0020] As a preferred solution of the present invention, in step 2, the number of channels excited simultaneously at a single time by the phased array ultrasonic detector is at least 32, and a linear array with at least 16 array elements is used.

[0021] As a preferred solution of the present invention, in step three, the thickness and material of the workpiece are set in the phased array ultrasonic detector operation interface according to the actual test piece in step 1, and the workpiece type is a welded joint.

[0022] As a preferred solution of the present invention, the step four sets the emission and reception mode to spontaneous emission and self-reception, sets the number of array elements that can be excited by the focusing law to at least 16, the fan angle step is not greater than 1°, the difference between the maximum or minimum sound beam angle in the fan scanning angle range and the natural refraction angle of the wedge should not be greater than 20°, the focusing mode is true depth focusing, the focusing depth is set to avoid being in the near field, and the step offset is adjusted so that the minimum angle and maximum angle of the primary wave can cover the middle and lower part of the weld and both sides of the heat affected zone, so that the minimum angle and maximum angle of the secondary wave outside the fusion line can cover the middle and upper part of the weld and both sides of the heat affected zone, and the primary wave and the secondary wave can cover the entire weld and the heat affected zone.

[0023] As a preferred solution of the present invention, the step five uses a carbon steel test block with a known material sonic velocity and a new wedge block.

[0024] As a preferred solution of the present invention, the fan scan display image in step six realizes a mirror display of the weld contour so that the starting depth and depth range of the observation parameter settings can at least present the detection area of ​​all welding joints within the fan scan range, adjust the display gain, and the imaging background noise echo is no higher than 20% of the screen.

[0025] As a preferred solution of the present invention, the scanning starting position 0 in step 5 and step 7 is the front view of the test block. Figure 1 The scanning area shall at least include the width of the test block, the pulse repetition frequency shall be at least 50 Hz and not more than 500 Hz, the scanning step shall not be greater than 1 mm, and the maximum scanning speed shall not cause interruptions in the scanning image.

[0026] As a preferred solution of the present invention, in step eight, the highest wave of the measured angle sound beam on the reflector is found, and the beam width is measured using the -6dB method in the C-scan view or the angle B-scan view of the unfused measured angle sound beam.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1. In the present invention, after the side through hole is processed on the surface of the test block, the bottom surface of the half-through hole is spherically formed to form an artificial reflector of the spherical half bottom surface. Since the surface is a spherical surface, different scanning directions and continuous different angle sound beam reflections can be realized. Therefore, the sound beam width of the angular sound beam with continuous different emission angles or deflection angles in the vertical cross-section can be measured, which makes up for the shortcomings of the national standard "Reference test blocks and methods for measuring contact probe sound beam characteristics for non-destructive ultrasonic testing" GB / T18852-2020 that the measurement method of the semicircular step (HS) test block is not rigorous and the measurement object cannot truly reflect the vertical cross-sectional sound beam width of the angular sound beam, and solves the problem that the national standard "Performance and inspection of phased array ultrasonic testing systems for non-destructive testing instruments" GB / T29302-2012 uses inclined angle through-hole test blocks, which is difficult to process, costly and cannot continuously measure the vertical cross-sectional sound beam width of angles at different angles, thereby filling the gap in relevant measurement standards.

[0029] 2. In the present invention, the lateral resolution can be calculated based on the width of the sound beam perpendicular to the cross-section of the angular sound beam, so as to determine the minimum detectable length of oriented defects such as lack of fusion, cracks, delamination, etc. that are perpendicular to the angle (when the sound beam width is larger than the defect size, the sound beam width is measured when measuring the defect, and the defect size cannot be measured), or the accuracy of measuring the defect length using the -6dB method and other length measurement methods based on the sound beam width is of great significance for objectively and accurately evaluating the quality grade of welds, castings, forgings or other formed workpieces according to the acceptance standards. In addition, accurate measurement of the sound beam width is of great significance for evaluating the sound beam coverage rate during the scanning process of the workpiece, so as to meet the specific requirements of different inspection standards for the sound beam coverage rate, achieve 100% full coverage of the sound beam, and avoid missed defects.

[0030] 3. In the present invention, according to the different forming processes or different sizes of the inspected workpieces such as welds, castings, forgings or others, and the different types and sizes of probes used, such as conventional single crystals and conventional double crystals, phased array linear and surface arrays and their TRL combination types, longitudinal waves and transverse waves, the material, length, width, thickness of the test block for measuring the sound beam width, and the number, distribution, size, etc. of the manhole reflectors are changed, the sound beam width of the vertical cross-section of the angle sound beam of the primary wave, secondary wave or multiple waves can be measured. It is suitable for measuring the sound beam width of different detection processes and has universal promotion significance. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the vertical cross-section sound beam width of the angle sound beam and the projection surface sound beam width;

[0032] Figure 2 It is a schematic diagram of the width of the sound beam projected on the driven axis direction of the angle sound beam measured by the flat bottom hole end angle emission echo;

[0033] Figure 3 This is a schematic diagram of the width of the acoustic beam in the direction of the driven axis of the angular acoustic beam emitted by the oblique through-hole cylinder;

[0034] Figure 4 This is the design drawing of the through hole test block on the bottom side of the ball;

[0035] Figure 5 This is a hemispherical bottom hole 302 with a depth of 30 mm, and a primary wave 45° angle acoustic beam imaging scan diagram;

[0036] Figure 6 This is a hemispherical bottom hole 302 with a depth of 30 mm and a primary wave 50° angle acoustic beam imaging scan diagram;

[0037] Figure 7 This is a hemispherical bottom hole 302 with a depth of 30 mm and a primary wave 55° angle acoustic beam imaging scan diagram;

[0038] Figure 8 This is a hemispherical bottom hole 302 with a depth of 50 mm, and a secondary wave 45° angle acoustic beam imaging scan;

[0039] Fig. 9 This is a hemispherical bottom hole 302 with a depth of 50 mm and a secondary wave 50° angle acoustic beam imaging scan diagram;

[0040] Fig.10 This is a hemispherical bottom hole 302 with a depth of 50 mm and a secondary wave 55° angle acoustic beam imaging scan. DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0042] For examples, see Figure 1-Figure 10 , the present invention provides a technical solution:

[0043] A method for measuring the width of an ultrasonic angle beam vertical cross section includes the following steps:

[0044] Step 1: Make a carbon steel test block with a length of L, a width of W, and a thickness of H, and process a spherical bottom semi-through hole artificial reflector with a length of F at different depths from the upper surface of the test block on the two end faces in the length direction of the test block, and the diameter Φ of the side through hole and the diameter Φ of the hemispherical bottom of the side through hole are not greater than 6mm. The length of the test block can at least meet the coverage of the secondary wave sound path on the artificial reflector, and the width of the test block can meet the wedge block scanning of the artificial reflector in the direction of the driven axis.

[0045] Step 2: Select a phased array ultrasonic detector with at least 32 channels of array elements for single simultaneous excitation, a phased array ultrasonic linear array probe with a center frequency not greater than 10 MHz and at least 16 array elements, and a shear wave wedge with a wedge angle of 36.2° and a natural refraction angle of 55°. Install the wedge on the probe and connect the probe to the detector.

[0046] Step 3: In the phased array ultrasonic detector operation interface, set the workpiece thickness to the actual workpiece thickness, the material to carbon steel, the workpiece type to flat butt weld, and the weld type to double V-type, so that the phased array ultrasonic detector image display interface shows the weld type to assist in defect interpretation.

[0047] Step 4: Set the focus law parameters, the acoustic wave emission and reception mode is self-transmission and self-reception, input the basic parameters of the actual array probe and wedge, set the number of array elements that can be excited to at least 16, the first array element number to be excited is 1, select the fan-shaped scanning mode, the angle step is not greater than 1°, the difference between the maximum or minimum sound beam angle in the fan-shaped scanning angle range and the natural refraction angle of the wedge should not be greater than 20°, the focusing mode is real depth focusing, and the focus depth setting should avoid being in the near field. Finally, adjust the step offset so that the minimum and maximum angles of the primary wave can cover the middle and lower part of the weld and both sides of the heat-affected zone, so that the minimum and maximum angles of the secondary wave at the fusion line can cover the middle and upper part of the weld and both sides of the heat-affected zone, and the primary and secondary waves can cover the entire weld and the heat-affected zone, thereby generating the focus law.

[0048] Step 5. Calibration: Use a test block with known material sound velocity, and do not need to perform sound velocity calibration. Use a new wedge without wedge calibration, perform TCG calibration (including ACG calibration), and finally select the encoder and perform encoder calibration.

[0049] Step 6: Set the ultrasonic parameters; set the starting depth and depth range of the display, and display the weld contour in a mirror image to ensure that at least the detection area of ​​all weld joints within the fan scan range can be presented. Adjust the gain so that the imaging background noise echo is no higher than 20% of the screen.

[0050] Step 7. Set the scanning parameters: the scanning starting point 0 is at one end of the test block in the width direction, the scanning area at least includes the width of the through hole on the bottom side of the hemisphere, the pulse repetition frequency is at least 50Hz and not more than 500Hz, the scanning step is not more than 1mm, and the combined setting of the maximum scanning speed and encoder resolution should not cause interruptions in the scanned image.

[0051] Step 8. After applying coupling agent on the test block, scan and collect test data. Use offline analysis software to analyze the saved data to find the highest wave of the measured angle sound beam on the reflector. Use the -6dB method to measure the imaging length in the C-scan view or the angle B-scan view of the unfused measured angle sound beam, thereby measuring the beam width. Specific embodiment:

[0053] Provide a more specific implementable scenario:

[0054] 1. Make a carbon steel ball bottom through-hole test block, the test block material is 20# steel, such as Figure 4 The specimen is 45mm thick, 450mm long, and 80mm wide. The depths of the artificial reflectors are 5mm and 25mm respectively. Figure 3 301 and 302. The other end of the test block in the length direction is processed with a hemispherical bottom through hole with a depth of 15mm and 35mm respectively, such as Figure 3 303 and 304. The diameter of the hemispherical bottom and the diameter of the side through hole are both 2mm, and the distance between the center of the spherical bottom and the side wall of the test block is 50mm. The surface roughness of all surfaces is 3.2, and the tolerances are: hole diameter, ±0.02mm; opening verticality, ±0.1°; other dimensions, ±0.05mm.

[0055] 2. Select a phased array ultrasonic detector with a maximum number of array elements for simultaneous excitation of 32 channels, a phased array ultrasonic linear array probe with a center frequency of 5 MHz, 32 array elements, an element width of 0.5 mm, an element gap of 0.1 mm, and a driven shaft aperture of 20 mm, and corresponding inclined wedges. The output waveform of the inclined wedges is a transverse wave, the wedge angle is 36.2°, the output angle is 55°, the first chip height is 7.97 mm, the main axis offset is 30.38 mm, the wedge driven axis width is 30 mm, and the secondary axis offset is 15 mm. Install the wedge on the probe and connect the probe to the phased array ultrasonic detector.

[0056] 3. In the phased array ultrasonic detector operation interface, set the workpiece thickness to the actual workpiece thickness of 32mm, select carbon steel as the material, the sound velocity to 5900m / s, the workpiece type to flat butt weld, the weld groove type to symmetrical double V-type, the blunt edge height of the groove to 0mm, the blunt edge offset to 3mm, the groove depth to 16, the groove angle to 74°, the weld width to 30mm, and the single-sided heat affected zone width to 5m, so that the phased array ultrasonic detector image display interface shows the weld type to assist in the interpretation of defects.

[0057] 4. Set the detection parameters without partitioning, use the primary wave to cover the weld joints in the middle and lower parts of the thickness direction, and use the secondary wave to cover the weld joints in the middle and upper parts of the thickness direction. The acoustic wave emission and reception mode is spontaneous, input the basic parameters of the array probe and the basic parameters of the shear wave wedge described in step 2 of the above implementation scenario, select the sector scanning mode, the wave type is shear wave, set the number of array elements that can be excited to 32, the sequence number of the first array element to be excited to 1, set the step offset to 30mm, set the minimum sector scanning angle to 35° and the maximum sector scanning angle to 70°, the angular resolution to 0.5°, the focusing mode to true depth focusing, and the focusing depth to 64mm, so as to generate the focusing law.

[0058] 5. Calibration: It is known that the shear wave sound velocity of the material is 3200m / s, so there is no need to perform sound velocity calibration. Use a new wedge without wedge calibration, then perform wedge delay calibration, and then perform TCG calibration (including ACG calibration).

[0059] 6. Set the ultrasonic parameters; set the starting depth of the display to 0mm and the depth range to 100mm when the minimum fan scanning angle is 35°, which can fully display the outline of the entire weld inspection area covered by the fan scanning, and set the display gain to 35dB.

[0060] 7. Set the scanning parameters: the starting point of the scan is the end of the wedge close to the width of the test piece, that is, the distance from the scan 0 point to one end of the test piece is half the width of the driven shaft of the wedge, which is 15mm, the scanning area range is 50mm, the pulse repetition frequency is 117Hz, the scanning step is 0.11mm, the maximum scanning speed is 1.0mm / s, and the encoder resolution is 8.73Steps / mm.

[0061] 8. Adjust different probe positions, and for the hemispherical bottom hole 302 with a depth of 30 mm, make the primary wave's 45°, 50°, and 55° angle sound beams obtain the maximum reflected wave amplitude respectively, simulate the situation at the fusion line on the left side of the defective weld, the left side inside the weld (volumetric defect), and the right side inside the weld, and scan and check respectively, and collect three groups of A, B, C, and S scanning images of the hemispherical hole 302, as shown in the figure. Figures 5 to 7 , save the data and use offline analysis software to analyze it. Figures 5 to 7In the C-scan view images 401, 501, 601 or the B-scan view images 402, 502, 602, the image length is measured using the -6dB method, which is the vertical cross-sectional sound beam width of the primary wave 45°, 50°, 55° angle sound beam at a depth of 30mm. The sound beam width values ​​are 4.51mm, 4.84mm, and 5.17mm, respectively, so that the corresponding lateral resolution can be calculated as 1.13mm, 1.21mm, and 1.29mm. Therefore, it can be judged that the primary wave 45° angle sound beam at the left fusion line of the weld depth of 30mm can at least distinguish defects with a length of 1.13mm perpendicular to its angle. It can be judged that the primary wave 50° angle sound beam on the left side of the weld can at least distinguish defects with a length of 1.21mm perpendicular to its angle. It can be judged that the primary wave 55° angle sound beam on the right side of the weld can at least distinguish defects with a length of 1.29mm perpendicular to its angle.

[0062] 9. Adjust different probe positions, and for the hemispherical bottom hole 304 with a depth of 40 mm, make the 45°, 50°, and 55° angle sound beams of the secondary wave obtain the maximum reflected wave amplitude respectively, simulate the situation at the fusion line on the left side of the defective weld, the left side of the weld (volumetric defect), and the right side of the weld, and scan and check respectively, and collect three groups of A, B, C, and S scanning images of the hemispherical hole 304, as shown in Figure 1. Figures 8 to 10 , save the data and use offline analysis software to analyze it. Figures 8 to 10 In the C-scan view images 701, 801, 901 or the B-scan view images 702, 802, 902, the image length is measured using the -6dB method, which is the vertical cross-sectional sound beam width of the secondary wave 45°, 50°, 55° angle sound beam at a depth of 40mm. The sound beam width values ​​are 5.39mm, 6.16mm, and 6.6mm, respectively, so that the corresponding lateral resolution can be calculated as 1.35mm, 1.54mm, and 1.65mm. Therefore, it can be judged that at the left fusion line of the actual depth of 14mm, the secondary wave 45° angle sound beam can at least distinguish defects with a minimum length of 1.13mm perpendicular to its angle. It can be judged that the secondary wave 50° angle sound beam on the left side of the weld can at least distinguish defects with a minimum length of 1.21mm perpendicular to its angle. It can be judged that the secondary wave 55° angle sound beam on the right side of the weld can at least distinguish defects with a minimum length of 1.29mm perpendicular to its angle.

[0063] The working process of the present invention is as follows: when using the ultrasonic angle sound beam vertical cross-section sound beam width measurement method designed in the scheme, a carbon steel test block with a length of L, a width of W, and a thickness of H is made, and an artificial reflector of a hemispherical bottom side through hole is processed at different depths from the upper surface of the test block on the side of the end face in the length direction of the test block, the diameter of the side through hole is Φ, the bottom surface of the side through hole is a hemispherical surface with a diameter of Φ, the distance from the center of the hemispherical bottom circle to the end face is F, and the roughness of each inner and outer surface, the diameter tolerance of the hole and the hemisphere, the verticality of the opening and other dimensional tolerances meet certain conditions; a phased array probe of a certain frequency, number of array elements, and array size is selected, a corresponding wedge is installed, and a phased array ultrasonic host is connected; the workpiece thickness, material, and workpiece type are set in the phased array ultrasonic detector operation interface; the focusing law parameters are set: the transmitting and receiving modes are set, the basic parameters of the probe and the basic parameters of the wedge are input, the number of array elements that can be excited, the serial number of the first array element to be excited, the sector scanning mode is selected, and the sector scanning minimum Beam angle and maximum beam angle, angle step, focusing mode and focusing depth (or distance), and finally set the step offset (the distance from the front edge of the wedge to the center line of the weld) so that the primary wave covers the middle and lower part of the weld and the heat-affected zone, and the secondary wave covers the middle and upper part of the weld and the heat-affected zone to ensure full coverage of the weld detection area, thereby generating a focusing law; Calibration: perform sound velocity calibration, then wedge delay calibration, then TCG calibration (including ACG calibration), and finally select the encoder to perform encoder calibration; Set ultrasonic parameters; mainly set the starting depth and depth range of the display, you can display the weld detection area, and adjust the display gain; Set scanning parameters: mainly set the scanning starting 0 point position, scanning area range, pulse repetition frequency, maximum scanning speed, scanning step, encoder polarity; After applying coupling agent on the test block, scan the artificial reflector of the through hole on the bottom side of the hemisphere, collect detection data, and use the saved data to measure the beam width using offline analysis software.

[0064] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for measuring the vertical cross-section beam width of an ultrasonic angle beam, using an artificial reflector with a through hole on the bottom side of a hemisphere, and measuring the vertical cross-section beam width of an angle beam with different continuous emission angles or deflection angles by pulse ultrasonic emission method, taking the ultrasonic detection process represented by phased array ultrasonic weld detection as an example, the method is characterized by: The following steps are involved: Step 1: Make a carbon steel test block with a length of L, a width of W, and a thickness of H, and process an artificial reflector with a through hole on the bottom of the hemisphere at different depths from the upper surface of the test block on the side of the end face in the length direction of the test block. The diameter of the side through hole is Φ, and the bottom surface of the side through hole is a hemisphere with a diameter of Φ. The distance from the center of the bottom of the hemisphere to the end face is F. The roughness of each inner and outer surface, the diameter tolerance of the hole and the hemisphere, the verticality of the opening and other dimensional tolerances meet certain conditions; Step 2: Select a phased array probe with a certain frequency, number of array elements, and array size, install the corresponding wedge, and connect the phased array ultrasound host; Step 3: Set the workpiece thickness, material, and workpiece type in the phased array ultrasonic detector operation interface; Step 4: Set the focus law parameters: Set the transmission and reception mode, input the basic parameters of the probe and the basic parameters of the wedge, set the number of array elements that can be excited, the sequence number of the first array element to be excited, select the sector scanning mode, set the minimum and maximum sound beam angles of the sector scanning, the angle step, the focusing mode and the focusing depth (or distance), and finally set the step offset (the distance from the front edge of the wedge to the center line of the weld) so that the primary wave covers the middle and lower part of the weld and the heat-affected zone, and the secondary wave covers the middle and upper part of the weld and the heat-affected zone, so as to ensure full coverage of the weld inspection area, thereby generating the focus law; Step 5: Calibration: perform sound velocity calibration, then wedge delay calibration, then TCG calibration (including ACG calibration), and finally select the encoder and perform encoder calibration; Step 6: Set the ultrasound parameters; Mainly set the starting depth and depth range of the display, can display the weld detection area, and adjust the display gain; Step 7: Set scanning parameters: mainly set the scanning starting 0 point position, scanning area range, pulse repetition frequency, maximum scanning speed, scanning step, and encoder polarity; Step 8: After applying coupling agent on the test block, scan the artificial reflector of the through hole on the bottom side of the hemisphere, collect the test data, and use the saved data to measure the sound beam width using offline analysis software.

2. The method for measuring the width of an ultrasonic angle beam vertical cross section according to claim 1, characterized in that: The length of the test block made in the step 1 can at least meet the coverage of the secondary wave sound path on the artificial reflector, the width of the test block can meet the scanning of the artificial reflector by the wedge block in the direction of the driven axis, and hemispherical bottom side through holes are provided on both end faces in the length direction of the test block. The diameter of the side through holes and the diameter of the hemispherical bottom surface should be smaller while meeting the processing tolerance conditions, and the roughness of each inner and outer surface should be smaller.

3. The method for measuring the width of an ultrasonic angle beam vertical cross section according to claim 1, characterized in that: In the step 2, the number of channels excited simultaneously at a single time by the phased array ultrasonic detector is at least 32, and a linear array with at least 16 array elements is used.

4. The method for measuring the width of an ultrasonic angle beam vertical cross section according to claim 1, characterized in that: In the step 3, the thickness and material of the workpiece are set in the phased array ultrasonic detector operation interface according to the actual test piece in step 1, and the workpiece type is a welded joint.

5. The method for measuring the width of an ultrasonic angle beam vertical cross section according to claim 1, characterized in that: The step 4 sets the transmitting and receiving mode to spontaneous transmission and self-reception, sets the number of array elements that can be excited by the focusing law to at least 16, the fan angle step is not greater than 1°, the difference between the maximum or minimum sound beam angle in the fan scanning angle range and the natural refraction angle of the wedge should not be greater than 20°, the focusing mode is true depth focusing, the focusing depth is set to avoid being in the near field, and the step offset is adjusted so that the minimum angle and maximum angle of the primary wave can cover the middle and lower part of the weld and both sides of the heat affected zone, so that the minimum angle and maximum angle of the secondary wave outside the fusion line can cover the middle and upper part of the weld and both sides of the heat affected zone, and the primary wave and the secondary wave can cover the entire weld and the heat affected zone.

6. The method for measuring the width of an ultrasonic angle beam vertical cross section according to claim 1, characterized in that: Step 5 uses a carbon steel test block with known material sonic velocity and a new wedge.

7. The method for measuring the width of an ultrasonic angle beam vertical cross section according to claim 1, characterized in that: The fan scan display image in step six realizes a mirror display of the weld contour so that the starting depth and depth range of the observation parameter settings can at least present the detection area of ​​all weld joints within the fan scan range, and the display gain is adjusted so that the imaging background noise echo is no higher than 20% of the screen.

8. The method for measuring the width of an ultrasonic angle beam vertical cross section according to claim 1, characterized in that: The scanning starting position 0 in step 5 and step 7 is the edge of one side of the front view of the test block, the scanning area range at least includes the width range of the test block, the pulse repetition frequency is at least 50 Hz and not more than 500 Hz, the scanning step is not more than 1 mm, and the maximum scanning speed is set so as not to cause interruptions in the scanned image.

9. The method for measuring the width of an ultrasonic angle beam vertical cross section according to claim 1, characterized in that: In the step eight, the highest wave of the measured angle sound beam on the reflector is found, and the beam width is measured using the -6 dB method in the C-scan view or the angle B-scan view of the measured angle sound beam without fusion.

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