Full-surface coverage array spiral guided wave imaging detection device and method

Abstract

The invention discloses a full-surface coverage array spiral guided wave imaging detection device and method, and relates to the field of ultrasonic nondestructive testing. The device comprises two transducer group arrays, and each transducer group array comprises a pipeline surrounding belt, a fixing belt and n transducer groups; each transducer group comprises a shell, two fixing rings arranged side by side and two ultrasonic guided wave transducers arranged side by side; n mounting holes are formed in the pipeline surrounding belt and the fixing belt at equal intervals in the length direction; the first fixing ring in each transducer group is correspondingly connected with the mounting hole in the pipeline surrounding belt, and the transducer group can rotate around the first fixing ring; the second fixing ring in each transducer group is correspondingly connected with the mounting hole in the fixing belt, and the fixing belt can move up and down in the length direction. The two transducer group arrays are fixed at the two ends of the detected pipeline, and the transducer groups at the two ends alternately carry out transmitting and receiving and then carry out synthetic calculation, so that the spiral pipeline defect detection efficiency and precision are greatly improved.

Description

Technical Field

[0001] The present application relates to the technical field of ultrasonic nondestructive testing, and in particular to a full-surface coverage array spiral guided wave imaging detection device and method. Background Art

[0002] Spiral welded pipes are usually made by spirally rolling steel strips into tube blanks at a certain forming angle, and then welding the spiral gaps between the tube blanks. They play an irreplaceable role in long-distance pipelines. Spiral welded pipes have a long service life and strong pressure-bearing capacity. They are currently widely used in petrochemical and other fields. Spiral welded pipes will experience internal and external corrosion, weld rust, external force damage, etc. during long-term transmission. If they are not manually inspected and repaired, they will leak and break. In order to avoid personal and property losses caused by the failure of spiral welded pipes, pipelines, especially welds, must be inspected and tested regularly.

[0003] Traditional pipeline inspection equipment and methods mainly use ultrasonic flaw detectors or detectors to inspect point by point, or use ultrasonic detection to emit ultrasonic waves parallel to the pipeline axis for inspection. The point-by-point inspection method will inevitably lead to detection loopholes, fail to fully cover the pipeline, and increase the inspection time. The detection method parallel to the axial direction is more suitable for ordinary vertical pipeline welding methods, and has poor welding inspection effect on spiral pipelines. This is because the weld of the spiral pipeline is spiral, and the defect position is more likely to appear on the spiral line. The ultrasonic emission direction is perpendicular to the defect position for the best detection effect. Summary of the invention

[0004] In response to the current problems of spiral pipeline detection, such as long detection time, low detection accuracy, and cumbersome operation, the present application provides a full-surface coverage array spiral guided wave imaging detection device and method to improve the efficiency and detection accuracy of spiral pipeline defect detection.

[0005] To achieve the above objectives, this application provides the following solutions.

[0006] On the one hand, the present application provides a full-surface coverage array spiral guided wave imaging detection device, comprising: two groups of transducer group arrays; each group of the transducer group arrays comprises a pipeline surrounding belt, a fixing belt and n transducer groups; each transducer group comprises a shell, two fixing rings arranged side by side and two ultrasonic guided wave transducers arranged side by side;

[0007] The pipe wrapping belt and the fixing belt are both provided with n mounting holes arranged at equal intervals along the length direction, and the distance between two adjacent mounting holes is f; the first fixing ring in each transducer group is correspondingly connected to the mounting hole on the pipe wrapping belt and the transducer group can rotate around the first fixing ring; the second fixing ring in each transducer group is correspondingly connected to the mounting hole on the fixing belt, and the fixing belt can move up and down along the length direction.

[0008] Optionally, the distance between two adjacent mounting holes is Where D is the diameter of the pipe being measured.

[0009] On the other hand, a full-surface coverage array spiral guided wave imaging detection method is based on the full-surface coverage array spiral guided wave imaging detection device; the full-surface coverage array spiral guided wave imaging detection method comprises:

[0010] Two groups of transducer arrays are respectively fixed at two ends of the measured pipeline along the circumference of the measured pipeline, and each transducer group in each group of transducer arrays faces the measured section of the measured pipeline;

[0011] The fixed belt positions of the two transducer arrays are adjusted along the circumference of the tested pipeline respectively, so that the direction of ultrasonic guided waves transmitted / received by each transducer array in the two transducer arrays is parallel to the weld of the tested pipeline;

[0012] Controlling n transducer groups of the first transducer group array to simultaneously transmit ultrasonic guided wave signals, wherein the ultrasonic guided wave signals propagate spirally in the measured pipeline along a direction parallel to the weld until being received by the second transducer group array; recording the echo signals measured by the second transducer group array as the first measurement result;

[0013] When the second transducer array receives the ultrasonic guided wave signal, it immediately transmits the ultrasonic guided wave signal with the same amplitude and power in the reverse direction, which is received by the first transducer array; and the echo signal measured by the first transducer array is recorded as the second measurement result;

[0014] The fixed belt positions of the two transducer arrays are adjusted along the circumference of the tested pipeline respectively, so that the direction of ultrasonic guided waves emitted / received by each transducer array in the two transducer arrays is perpendicular to the weld of the tested pipeline;

[0015] Controlling n transducer groups of the first transducer group array to simultaneously transmit ultrasonic guided wave signals, wherein the ultrasonic guided wave signals propagate spirally in the measured pipeline along the vertical direction of the weld until being received by the second transducer group array; recording the echo signals measured by the second transducer group array as the third measurement result;

[0016] When the second transducer array receives the ultrasonic guided wave signal, it immediately transmits the ultrasonic guided wave signal with the same amplitude and power in the reverse direction, which is received by the first transducer array; and the echo signal measured by the first transducer array is recorded as the fourth measurement result;

[0017] Composite imaging is performed based on the four measurement results to generate a defect detection image.

[0018] Optionally, the two transducer arrays are respectively fixed at two ends of the measured pipeline along the circumference of the measured pipeline, and each transducer group in each transducer array faces the measured section of the measured pipeline, specifically including:

[0019] The pipeline surrounding belts of the two transducer arrays are respectively wrapped around the measured pipeline, so that the two transducer arrays are fixed along the circumference of the measured pipeline;

[0020] Fixing the first transducer array group at the left end of the pipeline to be tested, so that each transducer group in the first transducer array group faces the right side;

[0021] The second transducer array is fixed at the right end of the measured pipeline, and each transducer group in the second transducer array faces the left side.

[0022] Optionally, before adjusting the position of the fixing belt along the circumference of the measured pipeline, the method further includes:

[0023] Use the angle ruler measurement method to measure and record the spiral angle of the spiral weld of the measured pipeline in real time.

[0024] Optionally, during the four measurement processes, the amplitude and power of the transmitted ultrasonic guided wave signal are the same.

[0025] Optionally, performing synthetic imaging based on the four measurement results to generate a defect detection image specifically includes:

[0026] Perform weighted calculation on the echo amplitude of each sampling data point in the four measurement results to obtain the comprehensive measurement echo amplitude of each sampling data point;

[0027] The comprehensive measurement echo amplitude of each sampling data point is matched to the color of the corresponding pixel point according to the amplitude gradient to generate a defect detection image.

[0028] Optionally, performing weighted calculation on the echo amplitude of each sampling data point in the four measurement results to obtain a comprehensive measurement echo amplitude of each sampling data point specifically includes:

[0029] Using formula P i =0.2*A i +0.2*B i +0.3*C i +0.3*D i Calculate the comprehensive measurement echo amplitude P of the i-th sampling data point i ; Among them A i , B i , C i , D i They respectively represent the echo amplitude of the i-th sampling data point in the four measurement results.

[0030] Optionally, after generating the defect detection image, the method further includes:

[0031] Identify defect categories and locations in defect inspection images.

[0032] Optionally, after identifying the defect category and position in the defect detection image, the method further includes:

[0033] Provide maintenance reminders based on defect type and location.

[0034] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0035] The present application provides a full-surface coverage array spiral guided wave imaging detection device and method, which utilizes a dual transducer structure in a single transducer group to offset the interference in the opposite direction of the transducer emission direction, realize the unidirectional and directional emission of ultrasonic guided waves, improve the emission efficiency, and reduce power consumption. Considering that the weld of the spiral welded pipe is spiral, the defect position is more likely to appear on the spiral weld, so a rotatable transducer group structure is proposed, wherein the first fixed ring is connected to the pipeline surrounding belt, the second fixed ring is connected to the fixed belt, and the transducer group can rotate around the first fixed ring, and the rotation method is to move the fixed belt up and down, so that it can realize two detection methods parallel and perpendicular to the weld. By fixing the two groups of transducer group arrays at the two ends of the measured pipeline along the circumference of the measured pipeline respectively, the transducer groups at the two ends alternately transmit and receive, and then perform synthetic calculations, the four measurement results are respectively for the four directions of the upper, lower, left and right directions of the weld position where the defects are most likely to exist. The full-surface coverage detection is carried out in all directions, which greatly improves the defect detection accuracy. Multiple transducers in each transducer group array transmit and receive simultaneously, which simplifies the operation process compared to the phased array method, increases the transmission power of the transducer group array, and makes the sound beam more uniform and controllable. Without using a phased array, it reduces hardware requirements and usage costs, shortens the development cycle, and greatly improves defect detection efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 Schematic diagram of the structure of two groups of transducer arrays;

[0038] Figure 2 is a schematic diagram of the structure of each transducer group in two transducer group arrays;

[0039] Figure 3 Schematic diagram of the ultrasonic guided wave emission direction of a single transducer and a combination of two transducers;

[0040] Figure 4 It is a schematic diagram of the arrangement of the mounting holes on the pipe surrounding belt and the fixing belt;

[0041] Figure 5 It is a schematic diagram of two groups of transducer arrays surrounding the pipeline to be tested along the circumferential direction;

[0042] Figure 6 A schematic diagram of the process of changing the orientation of the transducer group by moving the fixing belt;

[0043] Figure 7 Schematic diagram of the first measurement process parallel to the spiral weld direction;

[0044] Figure 8 It is a schematic diagram of the second measurement process parallel to the spiral weld direction;

[0045] Fig. 9 It is a schematic diagram of the third measurement process perpendicular to the spiral weld direction;

[0046] Fig.10 It is a schematic diagram of the fourth measurement process perpendicular to the spiral weld direction;

[0047] Fig.11 A schematic diagram of a defect detection image generated by the full surface coverage array spiral guided wave imaging detection method of the present application;

[0048] Fig.12 Schematic diagram of defect detection image generated by conventional method. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0050] The purpose of this application is to provide a full-surface coverage array spiral guided wave imaging detection device and method to improve the efficiency and accuracy of spiral pipeline defect detection.

[0051] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0052] The embodiment of the present application provides a full-surface coverage array spiral guided wave imaging detection device, comprising: two groups of transducer group arrays, in an initial non-measurement state, the first group of transducer group array structure is as follows Figure 1 As shown in part (a) of FIG. 1 , the array structure of the second transducer group is as follows: Figure 1 As shown in part (b) of the diagram, it can be seen that the two transducer arrays have the same structure, but are arranged in a mirror-symmetrical manner. Figure 1 As shown, each group of the transducer group array includes a pipe surrounding belt 1, a fixing belt 2 and n transducer groups 3.

[0053] Figure 2 Part (a) shows the structure of each transducer group in the first transducer group array, Figure 2 Part (b) shows the structure of each transducer group in the second transducer group array. Figure 2 As shown, each transducer group includes a housing 301, two fixed rings (a first fixed ring 302 and a second fixed ring 303) arranged side by side, and two ultrasonic guided wave transducers (a first ultrasonic guided wave transducer 304 and a second ultrasonic guided wave transducer 305) arranged side by side. The difference between the first transducer group array and the second transducer group array is that in the first transducer group array, Figure 2 As shown in part (a) of the invention, the two fixing rings are located on the left side of the two ultrasonic guided wave transducers (referred to as transducers); in the second transducer array, as shown in FIG. Figure 2 As shown in part (b) of the embodiment, the two fixing rings are located on the right side of the two transducers. That is to say, each transducer group structure in the first transducer group array and the second transducer group array is also arranged in mirror symmetry.

[0054] like Figure 3 As shown in part (a) of FIG. 1 , a conventional ultrasonic transducer uses a single transducer, and when performing detection, ultrasonic guided wave sound beams in two directions appear. However, the present application uses two ultrasonic guided wave transducers arranged side by side to achieve unidirectional emission of ultrasonic guided wave sound beams, such as Figure 3 As shown in parts (b) and (c) of the measurement. This is because the transmission direction of a single transducer is bidirectional, and the ultrasonic waves transmitted in two directions will be returned when encountering an obstacle. In this way, when the receiving end receives the return signal, it not only receives the echo signal in the direction of the object being measured, but also receives the echo signals in other directions, which affects the measurement result. The transducer group 3 of the present application can realize unidirectional transmission, because in each transducer group 3, the two transducers have the same direction and the same amplitude. After multiple transmission measurements, by adjusting the phase difference of the transmission signals of the two transducers, the ultrasonic guided waves emitted by the first transducer 304 in each transducer group 3 in its direction and back will be offset by the back ultrasonic guided waves of the second transducer 305, so that the transducer group 3 can realize unidirectional transmission, for example Figure 3Part (b) of FIG. 1 shows that the two transducers are emitted to the right, corresponding to Figure 2 The transducer group structure shown in part (a) of FIG. Figure 2 The transducer group structure shown in part (b) of FIG. 1 can emit ultrasonic guided wave sound beams to the left of the two transducers, such as Figure 3 As shown in part (c) of the embodiment of the present invention, by arranging two transducers in the transducer group 3 side by side, the influence of the emission of a single transducer on the transducer group array is reduced, and unidirectional sound beam emission can be achieved, thereby improving the measurement accuracy.

[0055] The pipeline surrounding belt 1 and the fixing belt 2 of the present application are both made of flexible materials. Figure 4 Part (a) shows the structure of the pipe surrounding belt 1 in the first transducer array. Figure 4 Part (b) shows the structure of the pipe surrounding belt 1 in the second transducer array. Figure 4 As shown in parts (a) and (b), the pipe surrounding belt 1 has n mounting holes 101 arranged at equal intervals along the length direction, and the distance between two adjacent mounting holes 101 is f. The pipe surrounding belts 1 in the two transducer arrays are arranged in mirror symmetry. Figure 4 Part (c) shows the structure of the fixing belt 2, as shown in FIG. Figure 4 As shown in part (c), the structures of the fixing belts 2 in the two transducer arrays are completely the same, and n mounting holes 201 are arranged at equal intervals along the length direction on the fixing belt 2, and the distance between two adjacent mounting holes 201 is also f. n is a positive integer.

[0056] See also Figure 1 When used in combination, for the first transducer group array or the second transducer group array, the first fixing ring 302 in each transducer group 3 is connected to the mounting hole 101 on the pipe surrounding belt 1, and the transducer group 3 can rotate around the first fixing ring 302. The second fixing ring 303 in each transducer group 3 is connected to the mounting hole 201 on the fixing belt 2, and the fixing belt 2 can move up and down along its length.

[0057] like Figure 5As shown, during actual measurement, the first transducer array 6 and the second transducer array 7 are respectively fixed at both ends of the measured pipeline (referred to as pipeline or pipeline) 4 along the circumference of the measured pipeline, and the middle part of the two transducer arrays is the measured section of the measured pipeline 4. For the first transducer array 6 or the second transducer array 7, by surrounding the respective pipeline surrounding belt 1 around the measured pipeline 4 along the circumference, the n transducer groups 3 in each transducer array can be arranged at equal intervals along the circumference of the measured pipeline (the fixing belt 2 is not shown for convenience of display). In some embodiments, the first fixing ring 302 in each transducer group 3 can be installed on the pipeline surrounding belt 1 by passing through the mounting hole 101 on the pipeline surrounding belt 1 and clamping, while making the transducer group 3 rotatable relative to the first fixing ring 302. Similarly, each transducer group 3 is clamped on the mounting hole 201 of the fixing belt 2 through the second fixing ring 303. At this time, by adjusting the fixing belt 2 to move up and down along the circumference of the pipeline 4, the orientation of the transducer group can be changed as a whole with the first fixing ring 302 as the rotation center, thereby changing the emission direction of the ultrasonic guided wave.

[0058] Taking the first transducer array 6 as an example, Figure 6 As shown in part (a) of FIG. 1 , if the fixing belt 2 is moved downward along the circumference of the pipeline (which is also the length direction of the fixing belt 2), the transducer group 3 can rotate clockwise, the direction of the transducer group 3 moves downward, and the emission direction of the ultrasonic guided wave (toward the right in the illustrated embodiment) also moves downward. Figure 6 As shown in part (b), if the fixing belt 2 is moved upward along the circumference of the pipeline, the transducer group 3 can rotate counterclockwise, the direction of the transducer group 3 moves upward, and the emission direction of the ultrasonic guided wave also moves upward. Figure 6 In the embodiment shown, the first fixing ring 302 is shown to be located on the left side of the second fixing ring 303. In practical applications, the first fixing ring 302 can also be arranged on the right side of the second fixing ring 303, which is equivalent to placing the first fixing ring 302 on the right side of the second fixing ring 303. Figure 6 The fixing belt 2 is placed on the left. If the fixing belt 2 is moved downward, the transducer group 3 is moved upward. Therefore, the two fixing rings of the present application are not limited to the relative positions shown in the figure. In other embodiments, the first fixing ring 302 can also be set to the right of the second fixing ring 303. Or, Figure 2 As shown in part (b), two fixing rings are arranged on the right side of the two transducers. No matter how they are arranged, the principle of changing the orientation of the transducer group 3 by moving the fixing belt 2 up and down is not affected. By changing the orientation of the transducer group 3, the directional emission of the ultrasonic guided wave sound beam can be achieved.

[0059] In view of the problems of long detection time, low detection accuracy and complicated operation in current spiral pipeline detection, this application proposes a new detection method, which uses ultrasonic guided wave detection technology to arrange multiple transducer groups at equal intervals along the 4 circumferences of the tested pipeline to form a double-row transducer array, such as Figure 1 and Figure 5 As shown. The number of transducer groups n is determined according to the pipe diameter D, and the calculation formula of the transducer group spacing (that is, the distance between two adjacent mounting holes of the pipe surrounding belt 1 or the fixing belt 2) f is as follows:

[0060]

[0061] Wherein D is the diameter of the measured pipe 4 , and n is the number of the transducer groups 3 .

[0062] Each time measurement is performed, two groups of transducer arrays are arranged along the circumference of the pipeline on both sides of a section of the pipeline (or pipeline) 4 to be measured, and the orientation of the transducer group 3 is arranged perpendicular to the spiral weld (weld) and parallel to the weld. In each arrangement, the left and right transducer arrays transmit and receive alternately, and the four measurement results are synthesized and calculated to obtain the final defect detection image.

[0063] The present application adopts a double-row ultrasonic guided wave transducer arrangement, uses phase difference to form directional ultrasonic guided waves for detection, adds a transducer group structure with adjustable direction, improves the compatibility of the weld direction, and can detect spiral welds perpendicular to the weld and parallel to the weld in sequence. By using the transducers arranged on both sides of the pipeline to transmit and receive alternately, and then synthesize and calculate the detection results, the detection accuracy of spiral welds can be greatly improved.

[0064] Based on the full surface coverage array spiral guided wave imaging detection device, the present application also proposes a full surface coverage array spiral guided wave imaging detection method. In some specific embodiments, the full surface coverage array spiral guided wave imaging detection method specifically includes the following steps 1 to 9.

[0065] Step 1: Use the angle ruler measurement method to measure the helical angle of the spiral weld 5 on the pipeline 4 in real time and record it. Subsequently, the overall orientation of the transducer group 3 (parallel or perpendicular to the weld 5) is arranged with reference to the helical angle.

[0066] Step 2: If Figure 7As shown, the first transducer array 6 is fixed to the left end of the measured pipe 4, and the second transducer array 7 is fixed to the right end of the measured pipe 4, by surrounding the entire transducer array on the pipe 4 with the pipe surrounding belt 1, so as to ensure that the number of transducer groups 3 in the first transducer array 6 and the second transducer array 7 are the same and the positions correspond one to one. It should be noted that the ultrasonic guided wave sound beams emitted by the two transducer arrays are in different directions, the first transducer array 6 is toward the right, and the second transducer array 7 is toward the left, so that both transducer arrays are toward the middle measured section.

[0067] Step 3: If Figure 7 and Figure 8 As shown, after fixing the two transducer group arrays, adjust the fixing belt 2 of the first transducer group array 6 to move upward along the circumference of the pipeline 4, so that each transducer group 3 rotates counterclockwise to drive it to move upward until the direction of the ultrasonic guided wave sound beam it emits is parallel to the weld 5; correspondingly, adjust the fixing belt 2 of the second transducer group array 7 to move downward along the circumference of the pipeline 4, so that each transducer group 3 rotates counterclockwise to drive it to move downward until the direction of the received ultrasonic guided wave sound beam is parallel to the weld 5.

[0068] Step 4: Control the n transducer groups 3 of the first transducer group array 6 to simultaneously emit ultrasonic guided wave sound beams, and excite directional guided wave signals parallel to the spiral weld direction along the entire surface of the pipe 4. The ultrasonic guided wave will propagate spirally in the pipe 4 along the parallel direction of the weld until it is received by the second transducer group array 7. The echo signal received by the second transducer group array 7 is recorded by the PC end and recorded as the first measurement result.

[0069] Step 5: When step 4 is completed and the second transducer array 7 receives the ultrasonic guided wave signal, it immediately transmits the ultrasonic guided wave sound beam with the same amplitude and power in the reverse direction, which is received by the first transducer array 6. Figure 8 As shown. The echo signal received by the first transducer array 6 is recorded by the PC as the second measurement result. The two measurements have the same amplitude and power. The first transducer array 6 and the second transducer array 7 transmit and receive alternately, forming two measurements in completely opposite directions. The upper and lower sides of the spiral weld defect position can be accurately measured, and the imaging result is more accurate.

[0070] Step 6: After the first two measurements, Fig. 9 and Fig.10As shown, the fixing belt 2 of the first transducer group array 6 is adjusted to move downward along the circumference of the pipeline 4, so that each transducer group 3 rotates clockwise to drive it to move downward until the direction of the ultrasonic guided wave sound beam it emits is perpendicular to the weld 5; correspondingly, the fixing belt 2 of the second transducer group array 7 is adjusted to move upward along the circumference of the pipeline 4, so that each transducer group 3 rotates clockwise to drive it to move upward until the ultrasonic guided wave sound beam emission and reception directions of the transducer group 3 are both perpendicular to the spiral weld 5.

[0071] Step 7: Control the first transducer array 6 to transmit and the second transducer array 7 to receive, so that the transducer group 3 can achieve directional transmission perpendicular to the weld. The result is recorded by the PC as the third measurement result.

[0072] Step 8: When step 7 is completed, the second transducer array 7 receives the ultrasonic guided wave signal, and the second transducer array 7 immediately transmits the ultrasonic guided wave sound beam with the same amplitude and power in the reverse direction, which is received by the first transducer array 6. Fig.10 The result is recorded by the PC as the fourth measurement result. These two measurements have the same amplitude and power as the previous two measurements, and are also transmitted and received alternately by the first transducer array 6 and the second transducer array 7, forming two measurements in completely opposite directions, which can accurately measure the left and right sides of the spiral weld defect position, and the imaging result is more accurate.

[0073] Step 9: The four measurement results are imaged and synthesized to generate a defect detection image. The defect type and location in the defect detection image can be further identified, and maintenance reminders can be given based on the defect type and location.

[0074] The present application performs four measurements on a single section of the measured pipeline 4, wherein when the ultrasonic guided wave emission direction is parallel to the weld direction, the first group of transducer arrays 6 emit and the second group of transducer arrays 7 receive, which is recorded as the first measurement result, and the second group of transducer arrays 7 emit and the first group of transducer arrays 6 receive, which is recorded as the second measurement result; when the ultrasonic guided wave emission direction is perpendicular to the weld direction, the first group of transducer arrays 6 emit and the second group of transducer arrays 7 receive, which is recorded as the third measurement result, and the second group of transducer arrays 7 emit and the first group of transducer arrays 6 receive, which is recorded as the fourth measurement result. Of course, in practical applications, the order of the four measurements is not limited. If the measurement order is adjusted, it is only necessary to adjust the imaging synthesis method accordingly according to the inventive concept of the present application.

[0075] The measured echo data is converted from ultrasonic echo signals to electrical signals through the transducer, and the electrical signals are converted into digital signals through the ADC chip and recorded on the PC. Set the sampling data points for each time to 40,000 data points. The first measurement results are recorded as A0, A1 to A39999 in sequence; the second measurement results are recorded as B0, B1 to B39999 in sequence; the third measurement results are recorded as C0, C1 to C39999 in sequence; and the fourth measurement results are recorded as D0, D1 to D39999 in sequence. The four measurement results are synthesized into a waveform point according to different weights. Because the possibility of detecting defects perpendicular to the defect position is greater than that parallel to the defect position, the third and fourth measurement results perpendicular to the weld have a weight of 0.6, and the first and second measurement results parallel to the weld have a weight of 0.4. Then, the echo amplitude of each sampling data point in the four measurement results can be weighted by formula (2) to obtain the comprehensive measurement echo amplitude of each sampling data point:

[0076] P i =0.2*A i +0.2*B i +0.3*C i +0.3*D i (2)

[0077] Among them A i , B i , C i , D i Respectively represent the echo amplitude of the i-th sampling data point in the four measurement results. i is the comprehensive measured echo amplitude of the i-th sampling data point. 0≤i≤39999.

[0078] After all the data points of the final four measurement results are calculated, the final 40,000 points are synthesized and the comprehensive measurement echo amplitude P of each sampling data point is calculated. i According to the amplitude gradient matching to the RGB color of the corresponding pixel point, the corresponding defect detection image can be generated and displayed on the PC interface as an RGB image. The imaging method of this application adopts RGB display. The PC receives the echo data and calculates the comprehensive measurement echo amplitude P of each data point. i , the echo amplitude is matched with the color according to the amplitude gradient. The lower the amplitude, the closer the color is to blue (or other colors), and the higher the amplitude, the lighter the color. Therefore, the defect area can be determined based on the light-colored area.

[0079] In a specific embodiment, the method of the present application is finally used to obtain the following Fig.11 The imaging results shown in the figure show that the measured spiral welded pipe has welding failure defects inside the pipe (light-colored area in the figure). Fig.12 As shown, compared Fig.11 and Fig.12 It can be seen that in the defect detection image measured using the method of the present application, the defect contour and shape are clearer and the detection result is more accurate.

[0080] Compared with conventional pipeline detection equipment and methods, the full-surface coverage array spiral guided wave imaging detection device and method of the present application has at least the following advantages:

[0081] 1) The sound beam emission of the traditional ultrasonic transducer is a bidirectional emission mode. When multiple transducers form an ultrasonic detection array, the traditional emission mode will interfere with the surrounding transducers, reduce the emission efficiency, and affect the power consumption. This application uses a double-row transducer array and uses the phase difference method to offset the interference in the opposite direction of the spiral line, thus realizing a unidirectional and directional ultrasonic guided wave beam.

[0082] 2) Compared with the phased array detection method, this application adopts a rotatable transducer group structure to adapt to a variety of spiral angles. Multiple transducers in each transducer group array transmit and receive simultaneously, which simplifies the operation process compared to the phased array method, increases the transmission power of the transducer group array, and makes the sound beam more uniform and controllable.

[0083] 3) Traditional ultrasonic testing equipment usually uses a one-time excitation and one-time reception method for calculation. This application uses transducer groups on both sides to alternately transmit and receive ultrasonic guided waves of the same amplitude and power. Two measurements in completely opposite directions can accurately measure the conditions on both sides of the defect position (up and down or left and right). With the rotatable transducer group, the detection is respectively perpendicular to the weld direction and parallel to the weld direction. Through four measurements, the measurement results of four directions of a defect position can be obtained, and then synthetic imaging can be performed based on this, which can significantly increase the detection accuracy.

[0084] 4) The guided wave detection technology used in this application is the most widely used technology in the field of non-destructive testing in long-distance detection scenarios such as pipelines. Compared with traditional ultrasonic detection methods, the advantage of long guided wave transmission distance is particularly prominent and is more suitable for pipeline detection.

[0085] 5) Considering that the weld of the spiral pipeline is spiral and the defect position is more likely to appear on the spiral line, this application has two detection methods perpendicular to the pipeline and parallel to the pipeline. By fixing two sets of transducer arrays at both ends of the tested pipeline along the circumference of the tested pipeline, the transducer groups at both ends are alternately transmitted and received, and then the synthesis calculation is performed. The four measurement results are respectively for the four directions of the upper, lower, left and right directions of the weld position where the defects are most likely to exist. All-round full-surface coverage detection is performed, and finally the detection results are synthesized according to different weights, which greatly improves the defect detection accuracy.

[0086] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A full surface coverage array spiral guided wave imaging detection device, characterized in that: include: Two groups of transducer arrays; each group of the transducer arrays includes a pipe surrounding belt, a fixing belt and n transducer groups; each transducer group includes a housing, two fixing rings arranged side by side and two ultrasonic guided wave transducers arranged side by side; The pipe wrapping belt and the fixing belt are both provided with n mounting holes arranged at equal intervals along the length direction, and the distance between two adjacent mounting holes is f; the first fixing ring in each transducer group is correspondingly connected to the mounting hole on the pipe wrapping belt and the transducer group can rotate around the first fixing ring; the second fixing ring in each transducer group is correspondingly connected to the mounting hole on the fixing belt, and the fixing belt can move up and down along the length direction.

2. The full surface coverage array spiral guided wave imaging detection device according to claim 1, characterized in that: The distance between two adjacent mounting holes is Where D is the diameter of the pipe being measured.

3. A full surface coverage array spiral guided wave imaging detection method, characterized in that: A full-surface-covered array spiral guided wave imaging detection device based on any one of claims 1-2; the full-surface-covered array spiral guided wave imaging detection method comprises: Two groups of transducer arrays are respectively fixed at two ends of the measured pipeline along the circumference of the measured pipeline, and each transducer group in each group of transducer arrays faces the measured section of the measured pipeline; The fixed belt positions of the two transducer arrays are adjusted along the circumference of the tested pipeline respectively, so that the direction of ultrasonic guided waves transmitted / received by each transducer array in the two transducer arrays is parallel to the weld of the tested pipeline; Controlling n transducer groups of the first transducer group array to simultaneously transmit ultrasonic guided wave signals, wherein the ultrasonic guided wave signals propagate spirally in the measured pipeline along a direction parallel to the weld until being received by the second transducer group array; recording the echo signals measured by the second transducer group array as the first measurement result; When the second transducer array receives the ultrasonic guided wave signal, it immediately transmits the ultrasonic guided wave signal with the same amplitude and power in the reverse direction, which is received by the first transducer array; and the echo signal measured by the first transducer array is recorded as the second measurement result; The fixed belt positions of the two transducer arrays are adjusted along the circumference of the tested pipeline respectively, so that the direction of ultrasonic guided waves emitted / received by each transducer array in the two transducer arrays is perpendicular to the weld of the tested pipeline; Controlling n transducer groups of the first transducer group array to simultaneously transmit ultrasonic guided wave signals, wherein the ultrasonic guided wave signals propagate spirally in the measured pipeline along the vertical direction of the weld until being received by the second transducer group array; recording the echo signals measured by the second transducer group array as the third measurement result; When the second transducer array receives the ultrasonic guided wave signal, it immediately transmits the ultrasonic guided wave signal with the same amplitude and power in the reverse direction, which is received by the first transducer array; and the echo signal measured by the first transducer array is recorded as the fourth measurement result; Composite imaging is performed based on the four measurement results to generate a defect detection image.

4. The full surface coverage array spiral guided wave imaging detection method according to claim 3 is characterized in that: The two transducer arrays are respectively fixed at two ends of the measured pipeline along the circumference of the measured pipeline, and each transducer group in each transducer array faces the measured section of the measured pipeline, specifically including: The pipeline surrounding belts of the two transducer arrays are respectively wrapped around the measured pipeline, so that the two transducer arrays are fixed along the circumference of the measured pipeline; Fixing the first transducer array group at the left end of the pipeline to be tested, so that each transducer group in the first transducer array group faces the right side; The second transducer array is fixed at the right end of the measured pipeline, and each transducer group in the second transducer array faces the left side.

5. The full surface coverage array spiral guided wave imaging detection method according to claim 3, characterized in that: Before adjusting the position of the fixing belt along the circumference of the measured pipeline, the method further comprises: Use the angle ruler measurement method to measure and record the spiral angle of the spiral weld of the measured pipeline in real time.

6. The full surface coverage array spiral guided wave imaging detection method according to claim 3, characterized in that: During the four measurements, the amplitude and power of the transmitted ultrasonic guided wave signals are the same.

7. The full surface coverage array spiral guided wave imaging detection method according to claim 3, characterized in that: The method of performing synthetic imaging based on the four measurement results to generate a defect detection image specifically includes: Perform weighted calculation on the echo amplitude of each sampling data point in the four measurement results to obtain the comprehensive measurement echo amplitude of each sampling data point; The comprehensive measurement echo amplitude of each sampling data point is matched to the color of the corresponding pixel point according to the amplitude gradient to generate a defect detection image.

8. The full surface coverage array spiral guided wave imaging detection method according to claim 7, characterized in that: The weighted calculation of the echo amplitude of each sampling data point in the four measurement results to obtain the comprehensive measurement echo amplitude of each sampling data point specifically includes: Using formula P i =0.2*A i +0.2*B i +0.3*C i +0.3*D i Calculate the comprehensive measurement echo amplitude P of the i-th sampling data point i ; Among them A i , B i , C i , D i They respectively represent the echo amplitude of the i-th sampling data point in the four measurement results.

9. The full surface coverage array spiral guided wave imaging detection method according to claim 3, characterized in that: After the defect detection image is generated, the method further includes: Identify defect categories and locations in defect inspection images.

10. The full surface coverage array spiral guided wave imaging detection method according to claim 9, characterized in that: After the defect category and position in the defect detection image are identified, the method further includes: Provide maintenance reminders based on defect type and location.

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