A diffraction time-of-flight ultrasonic detection method and device with dual probes placed on the same side

Abstract

The present invention relates to the field of weld detection technology, and in particular to a diffraction time difference ultrasonic detection method and device with dual probes placed on the same side, comprising the following steps: S1: two ultrasonic signal sources arranged in opposite directions perform ultrasonic detection on the corresponding straight section of the workpiece to be inspected and scan the straight section to obtain a corresponding comparison spectrum; S2: two ultrasonic signal sources perform ultrasonic detection on the corresponding curved section of the workpiece to be inspected and scan the curved section to obtain a detection spectrum; the curved section has a weld, and the two ultrasonic signal sources are arranged on the same side of the weld; S3: according to the comparison spectrum obtained in step S1, a baseline is set for the detection spectrum obtained in step S2, and the detection result of the weld is obtained by analysis. The present invention not only has a fast detection speed, but also has a higher accuracy of the detection result obtained based on the reference of the comparison spectrum.

Description

Technical Field

[0001] The invention relates to the technical field of weld detection, and in particular to a diffraction time-of-flight ultrasonic detection method and device with dual probes placed on the same side. Background Art

[0002] In the manufacturing and installation process of special equipment such as boilers, pressure vessels and pressure pipelines, non-destructive testing is an important means to ensure the quality of welds. The main detection methods for buried defects include: X-ray detection, ultrasonic detection, time-of-flight diffraction ultrasonic detection (TOFD detection) and phased array detection. Among them, TOFD detection uses the diffraction waves and propagation time difference generated by the longitudinal wave with the fastest sound speed in the solid at the end of the defect to detect, locate and quantify defects. The defect size determination does not rely on the signal amplitude, and the detection results are displayed in the form of images. During the detection, a pair of longitudinal wave oblique probes with the same frequency are placed symmetrically on both sides of the weld, one as a transmitting probe and the other as a receiving probe. The longitudinal wave emitted by the transmitting probe is incident on the weld to be inspected. In the defect-free area, the receiving probe will receive the straight wave propagating along the surface of the workpiece and the bottom surface reflection wave; when there is a defect, between the above two waves, the receiving probe will receive the diffraction waves at the upper and lower ends of the defect.

[0003] However, due to structural reasons, many important welds cannot be effectively inspected by existing inspection technologies, such as the fillet welds of the downcomer, the elbow welds of thick-walled pipes, and the flange welds. The welds in these parts cannot be inspected by radiography. Ultrasonic inspection and phased array inspection can only be performed on one side, and are greatly affected by the type and orientation of the defects, and are easy to miss for area defects. TOFD inspection cannot place two probes facing each other on both sides of the weld for inspection. Therefore, in the prior art, such as CN102507734A, a prior art named a method for ultrasonic time-difference diffraction inspection of welds, discloses that the two probes are placed on the same side of the weld for inspection, but the two probes placed on the same side of the weld for inspection cannot obtain a complete inspection map, so the position and depth information of the inspection weld are obtained by performing complex calculations through a set of binary quadratic equations, but this calculation method has deviated from the means of the TOFD inspection method, and there are problems such as complex inspection means and questionable accuracy of the inspection results. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a diffraction time-of-flight ultrasonic detection method and device with two probes placed on the same side, which can use the diffraction time-of-flight ultrasonic detection method to obtain the detection result of the weld by setting the two probes on the same side relative to the weld.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A diffraction time-of-flight ultrasonic detection method with two probes placed on the same side is provided, comprising the following steps:

[0007] S1: Two ultrasonic signal sources arranged in opposite directions perform ultrasonic detection on the corresponding straight sections of the workpiece to be inspected and scan the straight sections to obtain corresponding comparison maps;

[0008] S2: Two ultrasonic signal sources perform ultrasonic detection on the corresponding curved section of the workpiece to be inspected and scan the curved section to obtain a detection spectrum; the curved section has a weld, and the two ultrasonic signal sources are arranged on the same side of the weld;

[0009] S3: Setting a baseline for the detection map obtained in step S2 according to the comparison map obtained in step S1, and analyzing to obtain the detection result of the weld.

[0010] Another technical solution adopted by the present invention is:

[0011] A diffraction time-of-flight ultrasonic testing device with dual probes placed on the same side, comprising a fixing frame, an adjustment block and a probe clamping frame;

[0012] The fixing frame is provided with more than two first sliding grooves distributed along the circumference, and the first sliding grooves are in an arc shape adapted to the circumference;

[0013] The adjusting block is arranged on the fixing frame with a gap between the adjusting block and the fixing frame, and the fixing frame is provided with a second sliding groove matching the first sliding groove at a position corresponding to the first sliding groove;

[0014] A clamping portion for fixing two ultrasonic signal sources is provided at one end of the probe clamping frame, and a connecting portion respectively connected to the adjusting block and the fixing frame is provided at the other end of the probe clamping frame, and the connecting portion is located in the gap between the adjusting block and the fixing frame, and a latch is provided on the connecting portion, and the latch is movably inserted in the first slide groove and the second slide groove respectively.

[0015] The beneficial effects of the present invention are:

[0016] The present invention provides a diffraction time difference ultrasonic detection method and device with dual probes placed on the same side. In step S1, two ultrasonic signal sources are first used to scan the corresponding straight section of the workpiece to be inspected to obtain a corresponding comparison spectrum. The obtained comparison spectrum is consistent with the spectrum obtained by the traditional diffraction time difference ultrasonic detection method, so that a clear straight wave and bottom surface reflection wave can be obtained from the comparison spectrum as a reference line. Then, through step S2, the two ultrasonic signal sources are placed on the same side of the weld corresponding to the curved section of the workpiece to be inspected to perform ultrasonic detection and obtain a detection spectrum. The comparison spectrum is compared to the detection spectrum to set the baseline. After the detection spectrum is set with the baseline, it can be read through spectrum analysis, so as to quickly obtain the detection result of the corresponding weld in the detection spectrum. The present invention not only has a fast detection speed, but also has a higher accuracy of the detection result obtained based on the reference of the comparison spectrum. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a flowchart of the steps of a diffraction time-of-flight ultrasonic detection method in which two probes are placed on the same side of the present invention;

[0018] Figure 2 It is a schematic diagram of the arrangement positions of two ultrasonic signal sources in a diffraction time-of-flight ultrasonic detection method in which two probes are placed on the same side of the present invention;

[0019] Figure 3 It is a schematic diagram of the arrangement positions of two ultrasonic signal sources in a diffraction time-of-flight ultrasonic detection method in which two probes are placed on the same side of the present invention;

[0020] Figure 4 A comparison spectrum obtained in step S1 of a simulated flat plate test block containing defects using a diffraction time-of-flight ultrasonic testing method with two probes placed opposite to each other;

[0021] Figure 5 The detection spectrum is obtained in step S2 of a double-probe diffraction time-of-flight ultrasonic detection method in which two probes are placed on the same side of a defective simulated flat plate test block;

[0022] Figure 6 It is a structural schematic diagram of a diffraction time-of-flight ultrasonic detection device with two probes placed on the same side of the present invention;

[0023] Figure 7 It is a schematic structural diagram of a fixing frame of a diffraction time-of-flight ultrasonic detection device with dual probes placed on the same side of the present invention;

[0024] Figure 8 It is a structural schematic diagram of an adjustment block of a diffraction time-of-flight ultrasonic detection device with dual probes placed on the same side of the present invention;

[0025] Fig. 9It is a schematic structural diagram of a probe clamping frame of a diffraction time-of-flight ultrasonic detection device with two probes placed on the same side according to the present invention;

[0026] Description of labels:

[0027] 1. Ultrasonic signal source; 11. Sound wave transmitting probe; 12. Sound wave receiving probe;

[0028] 2. Workpiece to be inspected;

[0029] 3. Welding seam; 31. Welding seam defects;

[0030] 4. fixing frame; 41. first fixing part; 42. second fixing part; 411. first sliding groove; 412. first screw hole;

[0031] 5. adjusting block; 51. through hole; 52. second slide groove;

[0032] 6. Probe clamping frame; 61. Clamping portion; 62. Connecting portion; 63. Latch;

[0033] 7. Encoder. DETAILED DESCRIPTION

[0034] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in combination with the implementation modes and the accompanying drawings.

[0035] Please refer to Figures 1 to 5 In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0036] A diffraction time-of-flight ultrasonic detection method with two probes placed on the same side is provided, comprising the following steps:

[0037] S1: Two ultrasonic signal sources arranged in opposite directions perform ultrasonic detection on the corresponding straight sections of the workpiece to be inspected and scan the straight sections to obtain corresponding comparison maps;

[0038] S2: Two ultrasonic signal sources perform ultrasonic detection on the corresponding curved section of the workpiece to be inspected and scan the curved section to obtain a detection spectrum; the curved section has a weld, and the two ultrasonic signal sources are arranged on the same side of the weld;

[0039] S3: Setting a baseline for the detection map obtained in step S2 according to the comparison map obtained in step S1, and analyzing to obtain the detection result of the weld.

[0040] From the above description, it can be seen that the beneficial effect of the present invention is that: the present invention provides a diffraction time difference ultrasonic detection method and device with dual probes placed on the same side, by first using two ultrasonic signal sources in step S1 to scan the corresponding straight section of the workpiece to be inspected to obtain a corresponding comparison spectrum, the obtained comparison spectrum is consistent with the spectrum obtained by the traditional diffraction time difference ultrasonic detection method, so that a clear straight wave and bottom surface reflection wave can be obtained from the comparison spectrum as a reference line. Then through step S2, the two ultrasonic signal sources are placed on the same side of the weld corresponding to the curved section of the workpiece to be inspected to perform ultrasonic detection and obtain a detection spectrum, the comparison spectrum is compared to the detection spectrum to set the baseline, and after the detection spectrum is set with the baseline, it can be read through the spectrum analysis, so as to quickly obtain the detection result of the corresponding weld in the detection spectrum. The present invention not only has a fast detection speed, but also has a higher accuracy of the detection result obtained based on the reference of the comparison spectrum.

[0041] Furthermore, according to the thickness of the workpiece to be inspected and the incident angle parameters of the two ultrasonic signal sources, the spacing parameter between the two ultrasonic signal sources is calculated, and the positions of the two ultrasonic signal sources are set according to the spacing parameter; the calculation formula of the spacing parameter between the two ultrasonic signal sources is as follows:

[0042]

[0043] PCS is the distance between the two ultrasonic signal sources, t is the workpiece thickness, and α is the incident angle of the ultrasonic signal source.

[0044] Furthermore, the two ultrasonic signal sources disposed opposite to each other synchronously move a preset distance along the surface of the workpiece to be inspected, and the moving directions of the two ultrasonic signal sources disposed opposite to each other are perpendicular to the direction of a line connecting the two ultrasonic signal sources disposed opposite to each other.

[0045] From the above description, it can be seen that the two ultrasonic signal sources arranged opposite to each other can be synchronously moved along the surface of the workpiece to be inspected by a preset distance as needed. Preferably, the two ultrasonic signal sources arranged opposite to each other move one circle along the surface of the workpiece to be inspected, so that the entire comparison map is more complete.

[0046] Furthermore, the propagation angle between the two ultrasonic signal sources is adjusted so that the distance from the incident point of the sound beam of the ultrasonic signal source to the intersection point of the sound beams of the two ultrasonic signal sources is equal to half of the distance between the two ultrasonic signal sources in step S1.

[0047] From the above description, it can be seen that the intersection of the sound beams of the two ultrasonic signal sources is located at the center line of the weld. The sound beam incident point of the ultrasonic signal source is set to a distance from the intersection of the sound beams of the two ultrasonic signal sources equal to half of the spacing between the two ultrasonic signal sources. The corresponding diffraction wave signal of the weld defect in the obtained detection spectrum has higher clarity.

[0048] Please refer to Figures 6 to 9 , the present invention also provides a diffraction time-of-flight ultrasonic detection device with two probes placed on the same side, comprising a fixing frame, an adjustment block and a probe clamping frame;

[0049] The fixing frame is provided with more than two first sliding grooves distributed along the circumference, and the first sliding grooves are in an arc shape adapted to the circumference;

[0050] The adjusting block is arranged on the fixing frame with a gap between the adjusting block and the fixing frame, and the fixing frame is provided with a second sliding groove matching the first sliding groove at a position corresponding to the first sliding groove;

[0051] A clamping portion for fixing two ultrasonic signal sources is provided at one end of the probe clamping frame, and a connecting portion respectively connected to the adjusting block and the fixing frame is provided at the other end of the probe clamping frame, and the connecting portion is located in the gap between the adjusting block and the fixing frame, and a latch is provided on the connecting portion, and the latch is movably inserted in the first slide groove and the second slide groove respectively.

[0052] From the above description, it can be seen that the beneficial effect of the present invention is that: the connecting part of the probe clamping frame is arranged in the gap between the adjusting block and the fixed frame, and the connecting part is inserted in the first slide groove and the second slide groove by a pin, so that the probe clamping frame can move relative to the adjusting block and the fixed frame, so that the sound beam angles of the two ultrasonic signal sources can be adjusted by adjusting the positional relationship between the two clamping parts, so that the two ultrasonic signal sources can achieve the spacing and angle adjustment between the two ultrasonic signal sources according to the detection setting requirements, ensuring that the ultrasonic signal source and the detection surface can be in good contact when detecting a curved workpiece to be inspected.

[0053] Furthermore, the number of the first sliding grooves is two, and the two first sliding grooves are symmetrically arranged on the fixing frame.

[0054] It can be known from the above description that the two first slide grooves are symmetrically arranged on the fixing frame, so that the two clamping parts can adjust the spacing and angle relative to the first slide groove simultaneously towards or away from each other with reference to the symmetry axis.

[0055] Furthermore, the length of the second slide groove on the adjustment block is smaller than the length of the first slide groove, and one end of the second slide groove close to the symmetry axis overlaps with one end of the first slide groove close to the symmetry axis;

[0056] Two latches are arranged on the connecting portion of the probe clamping frame, one of the latches is movably inserted in the first sliding groove, and the other of the latches is movably inserted in the second sliding groove.

[0057] From the above description, it can be seen that the probe clamping frame moves along the arc direction corresponding to the first slide groove and the second slide groove through two pins to adjust the spacing and angle between the two probe clamping frames, so that the longitudinal wave oblique probes arranged on the two probe clamping frames form a certain angle along the circumferential direction, so that they can better form good contact with the detection surface of the curved surface of the workpiece to be detected.

[0058] Furthermore, the fixing frame includes a first fixing part, the two first sliding grooves are both arranged on the first fixing part, and the first fixing part is provided with a first screw hole at the position of the symmetry axis between the two first sliding grooves; a through hole adapted to the first screw hole is provided at the center of the adjusting block, and the first screw hole is connected to the through hole by adjusting the first section of the screw.

[0059] It can be known from the above description that the adjusting block and the fixing frame are fixed by means of screws connecting the first screw holes and the through holes, and the distance between the adjusting block and the fixing frame is set by means of the screws.

[0060] Furthermore, the fixing frame includes a second fixing portion, and an encoder is provided on the second fixing portion;

[0061] The second fixing part includes two connecting frames, the two connecting frames are respectively connected to the first fixing part, and the two connecting frames are respectively provided with connecting holes for the encoder body to pass through, and the encoder body is respectively embedded in the two connecting holes.

[0062] It can be seen from the above description that the encoder body is disposed between the two connecting frames and embedded in the two connecting holes, which can reduce the wear of the encoder body.

[0063] Please refer to Figures 1 to 3 , Embodiment 1 of the present invention is:

[0064] A diffraction time-of-flight ultrasonic detection method with two probes placed on the same side is provided, comprising the following steps:

[0065] S1: Two ultrasonic signal sources 1 arranged in opposite directions perform ultrasonic detection on the corresponding straight sections of the workpiece 2 to be inspected and scan the straight sections to obtain corresponding comparison maps;

[0066] Specifically, the two ultrasonic signal sources arranged opposite to each other are a pair of longitudinal wave oblique probes with the same frequency, and one of the two longitudinal wave oblique probes serves as an acoustic wave transmitting probe 11 to transmit longitudinal waves to the inspected weld, and the other serves as an acoustic wave receiving probe 12 to receive the straight wave propagating along the surface of the workpiece, the bottom surface reflected wave, and the diffraction waves at the upper and lower ends of the defect.

[0067] Two ultrasonic signal sources arranged opposite to each other are respectively clamped and fixed by a probe clamp and placed on a scanning frame, and the distance between the two ultrasonic signal sources is adjusted by the probe clamp. Specifically, according to the thickness of the workpiece to be inspected and the incident angle parameters of the two selected ultrasonic signal sources, the distance parameter between the two ultrasonic signal sources is calculated, and the positions of the two ultrasonic signal sources are set according to the distance parameter. The calculation formula of the distance parameter between the two ultrasonic signal sources is as follows:

[0068] Among them, PCS is the distance between the two ultrasonic signal sources, t is the workpiece thickness, and α is the incident angle of the ultrasonic signal source.

[0069] The detection surface of the workpiece to be inspected is preferably an arc surface, and the workpiece to be inspected includes a tubular, a tube-tube or a tube-plate shape. Preferably, the workpiece to be inspected is tubular, and the connection direction between the two ultrasonic signal sources arranged opposite to each other is perpendicular to the axial direction of the workpiece to be inspected. The two ultrasonic signal sources are respectively connected to the TOFD instrument, and the scanning frame drives the two ultrasonic signal sources arranged opposite to each other to move synchronously along the surface of the workpiece to be inspected by a preset distance, and the moving direction of the two ultrasonic signal sources arranged opposite to each other is perpendicular to the connection direction between the two ultrasonic signal sources arranged opposite to each other. Preferably, the two ultrasonic signal sources arranged opposite to each other are arranged around the circumference of the tubular workpiece to be inspected, and the corresponding comparison map is obtained by scanning.

[0070] Please refer to Figure 4 In principle, step S1 adopts the traditional diffraction time-difference ultrasonic testing method. An ultrasonic signal source serving as a sound wave transmitting probe transmits sound waves to the position of the workpiece to be inspected between the two ultrasonic signal sources and transmits longitudinal wave signals along the surface and inside of the workpiece to be inspected, while the other ultrasonic signal source serving as a sound wave receiving probe receives the straight-through waves and bottom-surface reflected waves propagating along the surface of the workpiece to be inspected. The comparison spectrum reflects the complete straight-through waves and bottom-surface reflected waves propagating along the surface of the workpiece to be inspected.

[0071] S2: Two ultrasonic signal sources perform ultrasonic detection on the corresponding curved section of the workpiece to be inspected and scan the curved section to obtain a detection spectrum; the curved section has a weld 3, and the two ultrasonic signal sources are arranged on the same side of the weld;

[0072] Specifically, the bent section of the workpiece to be inspected includes the connection position of the bent pipe and the straight pipe or the position of the angle bend of the boiler downtube. The wall thicknesses of the bent section and the straight section of the workpiece to be inspected are equal. The bent section has a weld, which is a corner weld of the boiler downtube, a butt weld between the bent pipe and the straight pipe, or a flange weld. The above welds all have the problem that two ultrasonic signal sources cannot be placed opposite to each other on both sides of the weld, so two ultrasonic signal sources are set on the same side of the weld for detection. And the connection direction between the two ultrasonic signal sources on the same side of the weld is in the same direction as the axial direction of the workpiece to be inspected. The probe is also clamped and fixed by a probe clamp and then placed on the scanning frame. It is synchronously moved along the weld track of the workpiece to be inspected for one circle to scan and obtain a detection spectrum.

[0073] Please refer to Figure 5 , the detection spectrum shows that when the two ultrasonic signal sources are arranged on the same side of the weld, the ultrasonic signal source as the sound wave receiving probe cannot receive the through wave and the bottom surface reflected wave propagating along the surface of the workpiece to be inspected, but the receiving probe receives the diffraction signal of the weld defect 31 propagating along the surface of the workpiece to be inspected, and the defect diffraction signal is stronger and more obvious in the detection spectrum.

[0074] S3: Setting a baseline for the detection map obtained in step S2 according to the comparison map obtained in step S1, and analyzing to obtain the detection result of the weld.

[0075] Specifically, the clear through wave and bottom reflection wave obtained in the comparison spectrum are used as the baseline. Since the comparison spectrum and the detection spectrum detect the same workpiece in different intervals, the through wave and bottom reflection wave in the comparison spectrum are used as the baseline to set the baseline in the detection spectrum, which makes up for the defect of the detection spectrum without a baseline. When analyzing the detection results of the weld, the TOFD detection method is used to first observe the phase relationship between the defect diffraction wave and the through wave to determine the type of defect, such as: upper surface open type, lower surface open type and buried type, and then determine the depth, width and length of the defect by moving the coordinates, and locate and quantify the defects in the weld.

[0076] In this embodiment, step S2 also includes: adjusting the propagation angle between the two ultrasonic signal sources so that the distance from the incident point of the sound beam of the ultrasonic signal source to the intersection point of the sound beams of the two ultrasonic signal sources is equal to half of the distance between the two ultrasonic signal sources in step S1.

[0077] See also Figures 6 to 9The present invention also provides a diffraction time difference method ultrasonic detection device with two probes placed on the same side, comprising a fixing frame 4, an adjustment block 5, a probe clamping frame 6 and an encoder 7. The fixing frame comprises a first fixing portion 41 and a second fixing portion 42, the cross section of the first fixing portion is rectangular, and the first fixing portion is provided with two first slide grooves 411 distributed along the circumference, and the first slide groove is in an arc shape adapted to the circumference. The two first slide grooves are symmetrically arranged, and the symmetry axes of the two first slide grooves are coaxial with the central axis of the first fixing portion. The first fixing portion is provided with a first screw hole 412 at the position of the symmetry axis of the two first slide grooves. The second fixing portion comprises two connecting frames, the two connecting frames are arranged at intervals, and one end of the two connecting frames is respectively connected to the two ends of one end surface of the first fixing portion. The two connecting frames are respectively provided with coaxially arranged connecting holes. The connecting hole is adapted to the encoder, and the two ends of the encoder body are respectively embedded in the two connecting holes.

[0078] The adjustment block is arc-shaped, and the adjustment block is arranged on the first fixing part of the fixing frame in a stacked manner, and there is a gap between the adjustment block and the fixing frame. Specifically, a through hole 51 adapted to the first screw hole of the fixing frame is provided at the center position of the adjustment block, and the first screw hole and the through hole are connected by an adjusting first section screw. The adjustment block and the fixing frame are fixed by the adjusting first section screw, and the size of the gap between the adjustment block and the fixing frame can be adjusted by tightening the adjusting first section screw. The adjustment block is provided with a second slide groove 52 adapted to the first slide groove at the position corresponding to the first slide groove. The length of the second slide groove is less than the length of the first slide groove, and the end of the second slide groove close to the axis of symmetry overlaps with the end of the first slide groove close to the axis of symmetry.

[0079] There are two probe clamps, one end of which is provided with a clamping portion 61 for fixing two ultrasonic signal sources 1, and the other end of which is provided with a connecting portion 62 respectively connected to the adjusting block and the fixing frame. The probe clamp is in a U-shape, and coaxially arranged screw holes are respectively arranged on the two oppositely arranged side walls of the U-shape corresponding to the probe clamp. The two ultrasonic signal sources are a pair of longitudinal wave oblique probes with the same frequency, and the longitudinal wave oblique probes are adapted to the U-shape corresponding to the probe clamp. The longitudinal wave oblique probes are embedded in the groove of the U-shape corresponding to the clamp, and the longitudinal wave oblique probes are provided with fixing holes corresponding to the screw holes. The longitudinal wave oblique probes are fixed to the probe clamp by screwing. The connecting portion of the probe clamp is located in the gap between the adjusting block and the fixing frame, and two latches 63 are arranged on the connecting portion, one of which is movably inserted in the first slide groove, and the other is movably inserted in the second slide groove. The latch inserted in the first slide groove is arranged away from the symmetry axis of the two first slide grooves, and the latch inserted in the second slide groove is arranged close to the symmetry axis of the two first slide grooves. Specifically, the latch is a second adjustment screw, and the two probe clamps are respectively moved along the arc direction corresponding to the first slide groove and the second slide groove by the latch to adjust the spacing and angle between the two probe clamps, so that the longitudinal wave oblique probes arranged on the two probe clamps form a certain angle along the circumferential direction, so as to better form good contact with the detection surface of the curved surface of the workpiece to be detected.

[0080] In summary, the present invention provides a diffraction time difference ultrasonic detection method with dual probes placed on the same side. In step S1, two ultrasonic signal sources are first used to scan the corresponding straight section of the workpiece to be inspected to obtain a corresponding comparison spectrum. The obtained comparison spectrum is consistent with the spectrum obtained by the traditional diffraction time difference ultrasonic detection method, so that a clear straight wave and bottom surface reflection wave can be obtained from the comparison spectrum as a reference line. Then, through step S2, the two ultrasonic signal sources are placed on the same side of the weld corresponding to the curved section of the workpiece to be inspected to perform ultrasonic detection and obtain a detection spectrum. The comparison spectrum is compared to the detection spectrum to set the baseline. After the detection spectrum is set with the baseline, it can be read through spectrum analysis, so as to quickly obtain the detection result of the corresponding weld in the detection spectrum. The present invention not only has a fast detection speed, but also has a higher accuracy of the detection result obtained based on the reference of the comparison spectrum. The present invention provides a diffraction time-difference ultrasonic detection device with two probes placed on the same side, wherein the connecting portion of the probe clamping frame is arranged in the gap between the adjusting block and the fixing frame, and the connecting portion is inserted into the first slide groove and the second slide groove by a latch, so that the probe clamping frame can move relative to the adjusting block and the fixing frame, thereby being able to adjust the sound beam angles of the two ultrasonic signal sources by adjusting the positional relationship between the two clamping portions, so that the two ultrasonic signal sources can achieve the spacing and angle adjustment between the two ultrasonic signal sources according to the detection setting requirements, ensuring that the ultrasonic signal source is in good contact with the detection surface when detecting a workpiece to be inspected with a curved surface.

[0081] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A diffraction time-of-flight ultrasonic detection method with two probes placed on the same side, characterized in that: The following steps are involved: S1: Two ultrasonic signal sources arranged in opposite directions perform ultrasonic detection on the corresponding straight sections of the workpiece to be inspected and scan the straight sections to obtain corresponding comparison maps; S2: Two ultrasonic signal sources perform ultrasonic detection on the corresponding curved section of the workpiece to be inspected and scan the curved section to obtain a detection spectrum; the curved section has a weld, and the two ultrasonic signal sources are arranged on the same side of the weld; S3: Setting a baseline for the detection spectrum obtained in step S2 according to the comparison spectrum obtained in step S1, wherein the baseline is the through wave and the bottom surface reflected wave of the comparison spectrum, and analyzing to obtain the detection result of the weld.

2. According to claim 1, a diffraction time-of-flight ultrasonic detection method with two probes placed on the same side is characterized in that: Step S1 is specifically as follows: According to the thickness of the workpiece to be inspected and the incident angle parameters of the two ultrasonic signal sources, the spacing parameter between the two ultrasonic signal sources is calculated, and the positions of the two ultrasonic signal sources are set according to the spacing parameter; the calculation formula of the spacing parameter between the two ultrasonic signal sources is as follows: PCS is the distance between the two ultrasonic signal sources, t is the thickness of the workpiece to be inspected, and α is the incident angle of the ultrasonic signal source.

3. According to claim 1, a diffraction time-of-flight ultrasonic detection method with two probes placed on the same side is characterized in that: Step S1 also includes: Two ultrasonic signal sources disposed opposite to each other synchronously move a preset distance along the surface of the workpiece to be inspected, and the moving directions of the two ultrasonic signal sources disposed opposite to each other are perpendicular to the direction of the line connecting the two ultrasonic signal sources disposed opposite to each other.

4. The method of ultrasonic detection by time-of-flight diffraction with dual probes placed on the same side according to claim 1, characterized in that: Step S2 also includes: The propagation angle between the two ultrasonic signal sources is adjusted so that the distance from the incident point of the sound beam of the ultrasonic signal source to the intersection point of the sound beams of the two ultrasonic signal sources is equal to half of the distance between the two ultrasonic signal sources in step S1.

5. The method of ultrasonic detection by time-of-flight diffraction with dual probes placed on the same side according to claim 1, characterized in that: The detection result of step S3 is specifically: Locate and quantify defects in welds.

6. A diffraction time-of-flight ultrasonic detection device with two probes placed on the same side, characterized in that: It includes a fixing frame, an adjusting block and a probe clamping frame; The fixing frame is provided with more than two first sliding grooves distributed along the circumference, and the first sliding grooves are in an arc shape adapted to the circumference; The adjusting block is arranged on the fixing frame with a gap between the adjusting block and the fixing frame, and the adjusting block is provided with a second sliding groove matching the first sliding groove at a position corresponding to the first sliding groove; One end of the probe clamping frame is provided with a clamping portion for fixing two ultrasonic signal sources, and the other end of the probe clamping frame is provided with a connecting portion respectively connected to the adjusting block and the fixing frame, and the connecting portion is located in the gap between the adjusting block and the fixing frame, and the connecting portion is provided with a latch, and the latch is movably inserted in the first slide groove and the second slide groove respectively; the number of the first slide grooves is two, and the two first slide grooves are symmetrically arranged on the fixing frame; The fixing frame comprises a first fixing part, the two first sliding grooves are both arranged on the first fixing part, the first fixing part is provided with a first screw hole at the position of the symmetry axis between the two first sliding grooves; the center of the adjusting block is provided with a through hole adapted to the first screw hole, and the first screw hole is connected to the through hole by a first screw; The length of the second slide groove on the adjustment block is less than that of the first slide groove, and an end of the second slide groove close to the symmetry axis overlaps with an end of the first slide groove close to the symmetry axis; Two latches are arranged on the connecting portion of the probe clamping frame, one of the latches is movably inserted in the first sliding groove, and the other of the latches is movably inserted in the second sliding groove.

7. The ultrasonic detection device of time-of-flight diffraction method with two probes placed on the same side according to claim 6, characterized in that: The fixing frame comprises a second fixing portion, and an encoder is provided on the second fixing portion; The second fixing part includes two connecting frames, the two connecting frames are respectively connected to the first fixing part, and the two connecting frames are respectively provided with connecting holes for the encoder body to pass through, and the encoder body is respectively embedded in the two connecting holes.

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