Double-layer bellows defect detection method, test block and device based on ultrasonic guided waves

Abstract

The present invention provides a double-layer bellows defect detection method, test block and device based on ultrasonic guided wave, which relates to the field of flaw detection technology. The method comprises: obtaining an outer layer standard DAC curve group based on the scanning results of a plurality of first simulated defects using a waveguide probe; obtaining an inner layer standard DAC curve group based on the scanning results of a plurality of second simulated defects using a waveguide probe; detecting the outer layer defects of the target double-layer bellows based on the first circumferential scanning results of the outer layer of the target double-layer bellows using the waveguide probe and the outer layer standard DAC curve group; detecting the inner layer defects of the target double-layer bellows based on the second circumferential scanning results of the inner layer of the target double-layer bellows using the waveguide probe and the inner layer standard DAC curve group. The present invention can reduce the time and difficulty of detecting double-layer bellows defects, and improve the accuracy of detection, thereby improving the efficiency of detecting double-layer bellows defects.

Description

Technical Field

[0001] The present invention relates to the technical field of flaw detection, and in particular to a double-layer bellows defect detection method, a test block and a device based on ultrasonic guided waves. Background Art

[0002] In gas-insulated metal-enclosed switchgear (GIS) equipment, double-layer bellows are often installed at the junctions of segmented busbars to compensate for horizontal and vertical displacement caused by pipeline installation errors, thermal expansion and contraction, mechanical vibration, and uneven foundation settlement. Under the influence of complex external environments and long-term alternating operating stresses, double-layer bellows are prone to developing harmful defects such as cracks and pitting during operation. These defects can easily cause gas transmitted through the equipment to leak, seriously affecting the safe and stable operation of power grid equipment. Therefore, it is necessary to detect defects in double-layer bellows.

[0003] Existing methods for detecting defects in double-layer bellows primarily include manual visual inspection, penetrant testing based on penetrant testing technology, and flaw detection, which requires installing corresponding ultrasonic guided wave probes at the peaks and troughs of the bellows. However, manual visual inspection relies on the experience of the inspector, making it difficult to detect all defects in the bellows and resulting in low detection accuracy. Penetrant testing requires applying reagents to the entire surface of the bellows, and the penetration and imaging process takes a long time. It also places certain requirements on the light source and lighting conditions during testing, making it difficult to observe defects during testing, and the use of reagents can easily cause environmental pollution. Existing flaw detection methods require installing a large number of guided wave probes based on the number of peaks and troughs, resulting in numerous inspections. The inspection process requires a significant amount of time and steps to select the guided wave probes corresponding to the curvature surface and carefully determine their specific locations. Furthermore, when inspecting the inner layer of a double-layer bellows, the installed double-layer bellows must be removed from the corresponding equipment, further increasing the number of steps. In summary, existing methods for detecting defects in double-layer bellows are time-consuming, difficult, and have poor accuracy, resulting in low detection efficiency. Summary of the Invention

[0004] One object of the present invention is to provide a method for detecting defects in double-layer bellows using ultrasonic guided waves, to address the problems of existing methods for detecting defects in double-layer bellows, such as long detection times, high difficulty, poor detection accuracy, and thus low detection efficiency. Another object of the present invention is to provide a test block. Another object of the present invention is to provide a device for detecting defects in double-layer bellows using ultrasonic guided waves. Another object of the present invention is to provide a computer device. Another object of the present invention is to provide a readable medium.

[0005] In order to achieve the above objectives, one aspect of the present invention discloses a double-layer corrugated pipe defect detection method based on ultrasonic guided waves, comprising:

[0006] Based on the scanning results of multiple first simulated defects of the outer layer inspection test block using a waveguide probe, an outer layer standard DAC curve group is obtained; based on the scanning results of multiple second simulated defects of the inner layer inspection test block using a waveguide probe, an inner layer standard DAC curve group is obtained; the outer layer inspection test block includes a first test block double-layer bellows and multiple first simulated defects arranged on the first test block double-layer bellows; wherein the first simulated defects include multiple first circumferential grooves in a preset first circumferential groove area, multiple first through holes in a preset first through hole area, and multiple first special grooves in a preset first special groove area, respectively arranged on the outer layer of the first test block double-layer bellows; the inner layer inspection test block includes a second test block double-layer bellows and multiple second simulated defects arranged on the second test block double-layer bellows; wherein the second simulated defects include multiple second circumferential grooves in a preset second circumferential groove area, multiple second through holes in a preset second through hole area, and multiple second special grooves in a preset second special groove area, respectively arranged on the inner layer of the second test block double-layer bellows;

[0007] Based on the first circumferential scanning result of the outer layer of the target double-layer corrugated pipe using the waveguide probe and the outer layer standard DAC curve group, the outer layer defects of the target double-layer corrugated pipe are detected; based on the second circumferential scanning result of the inner layer of the target double-layer corrugated pipe using the waveguide probe and the inner layer standard DAC curve group, the inner layer defects of the target double-layer corrugated pipe are detected.

[0008] Optionally, the first circumferential grooves are respectively arranged on the inner surface of a plurality of first preset wave crests and the outer surface of a plurality of first preset wave troughs of the outer layer of the double-layer corrugated tube of the first test block.

[0009] Optionally, the first through holes are respectively arranged on a plurality of the first preset wave crests and a plurality of the first preset wave troughs of the outer layer of the double-layer corrugated tube of the first test block.

[0010] Optionally, the first special grooves include a plurality of first inclined grooves forming a first angle with the circumferential direction and a plurality of second inclined grooves forming a second angle with the circumferential direction; wherein the first angle and the second angle are acute angles.

[0011] Optionally, the first inclined grooves are respectively arranged on the inner surfaces of multiple first preset peaks and the outer surfaces of multiple first preset troughs of the outer layer of the double-layer corrugated tube of the first test block; the second inclined grooves are respectively arranged on the inner surfaces of multiple first preset peaks and the outer surfaces of multiple first preset troughs of the outer layer of the double-layer corrugated tube of the first test block.

[0012] Optionally, the circumferential spacing distance between multiple first simulated defects set at the same wave crest of the first test block double-layer corrugated tube is greater than the preset first defect spacing distance; the circumferential spacing distance between multiple first simulated defects set at the same wave trough of the first test block double-layer corrugated tube is greater than the first defect spacing distance.

[0013] Optionally, the second circumferential grooves are respectively arranged on the inner surface of multiple second preset peaks and the outer surface of multiple second preset troughs of the inner layer of the double-layer corrugated tube of the second test block.

[0014] Optionally, the second through holes are respectively arranged at a plurality of the second preset wave crests and a plurality of the second preset wave troughs of the inner layer of the double-layer corrugated tube of the second test block.

[0015] Optionally, the second special grooves include a plurality of third inclined grooves forming a third angle with the circumferential direction and a plurality of fourth inclined grooves forming a fourth angle with the circumferential direction; wherein the third angle and the fourth angle are acute angles.

[0016] Optionally, the third inclined grooves are respectively arranged on the inner surface of multiple second preset peaks and the outer surface of multiple second preset troughs of the inner layer of the double-layer corrugated tube of the second test block; the fourth inclined grooves are respectively arranged on the inner surface of multiple second preset peaks and the outer surface of multiple second preset troughs of the inner layer of the double-layer corrugated tube of the second test block.

[0017] Optionally, the circumferential spacing distance between multiple second simulated defects set at the same wave crest of the second test block double-layer corrugated tube is greater than the preset second defect spacing distance; the circumferential spacing distance between multiple second simulated defects set at the same wave trough of the second test block double-layer corrugated tube is greater than the second defect spacing distance.

[0018] Optionally, obtaining the outer layer standard DAC curve group based on the scanning results of the plurality of the first simulated defects using a waveguide probe includes:

[0019] According to the scanning results of the plurality of first simulated defects, a first circumferential groove echo gain corresponding to each first circumferential groove, a first through-hole DAC equivalent line, a first through-hole echo gain corresponding to each first through-hole, a first oblique groove echo gain corresponding to each first oblique groove, a second oblique groove DAC equivalent line, and a second oblique groove echo gain corresponding to each second oblique groove are obtained;

[0020] Obtaining a first outer layer standard DAC curve according to the first circumferential groove echo gain, the first through-hole DAC equivalent line, and the first through-hole echo gain;

[0021] Obtaining a second outer layer standard DAC curve according to the first inclined groove echo gain, the second inclined groove DAC equivalent line and the second inclined groove echo gain;

[0022] The first outer layer standard DAC curve and the second outer layer standard DAC curve are clustered to obtain an outer layer standard DAC curve group.

[0023] Optionally, obtaining a first outer layer standard DAC curve according to the first circumferential groove echo gain, the first through-hole DAC equivalent line, and the first through-hole echo gain includes:

[0024] subtracting the corresponding first through-hole echo gain from each first circumferential groove echo gain to obtain a plurality of first gain differences, and taking an average of the plurality of first gain differences as a first average gain difference;

[0025] Performing a gain operation on the first through-hole DAC equivalent line based on the first average gain difference to obtain a first quantitative line;

[0026] A gain operation is performed on the first quantitative line based on a preset first optimized gain equivalent to obtain the first outer standard DAC curve.

[0027] Optionally, obtaining a second outer layer standard DAC curve according to the first inclined groove echo gain, the second inclined groove DAC equivalent line and the second inclined groove echo gain includes:

[0028] subtracting the corresponding second inclined groove echo gain from each first inclined groove echo gain to obtain a plurality of second gain differences, and taking an average of the plurality of second gain differences as a second average gain difference;

[0029] Performing a gain operation on the second inclined groove DAC equivalent line based on the second average gain difference to obtain a second quantitative line;

[0030] A gain operation is performed on the second quantitative line based on a preset second optimized gain equivalent to obtain the second outer layer standard DAC curve.

[0031] Optionally, obtaining the inner layer standard DAC curve group based on the scanning results of the plurality of second simulated defects using a waveguide probe includes:

[0032] According to the scanning results of the plurality of second simulated defects, a second circumferential groove echo gain corresponding to each second circumferential groove, a second through-hole DAC equivalent line, a second through-hole echo gain corresponding to each second through-hole, a third oblique groove echo gain corresponding to each third oblique groove, a fourth oblique groove DAC equivalent line, and a fourth oblique groove echo gain corresponding to each fourth oblique groove are obtained;

[0033] Obtaining a first inner layer standard DAC curve according to the second circumferential groove echo gain, the second through-hole DAC equivalent line, and the second through-hole echo gain;

[0034] Obtaining a second inner layer standard DAC curve according to the third inclined groove echo gain, the fourth inclined groove DAC equivalent line and the fourth inclined groove echo gain;

[0035] The first inner layer standard DAC curve and the second inner layer standard DAC curve are clustered to obtain an inner layer standard DAC curve group.

[0036] Optionally, obtaining the first inner layer standard DAC curve according to the second circumferential groove echo gain, the second through-hole DAC equivalent line, and the second through-hole echo gain includes:

[0037] Subtracting the corresponding second through-hole echo gain from each second circumferential groove echo gain to obtain a plurality of third gain differences, and taking an average of the plurality of third gain differences as a third average gain difference;

[0038] Performing a gain operation on the second through-hole DAC equivalent line based on the third average gain difference to obtain a third quantitative line;

[0039] A gain operation is performed on the third quantitative line based on a preset third optimized gain equivalent to obtain the first inner layer standard DAC curve.

[0040] Optionally, obtaining a second inner layer standard DAC curve according to the third inclined groove echo gain, the fourth inclined groove DAC equivalent line and the fourth inclined groove echo gain includes:

[0041] subtracting the corresponding fourth inclined groove echo gain from each third inclined groove echo gain to obtain a plurality of fourth gain differences, and taking an average of the plurality of fourth gain differences as a fourth average gain difference;

[0042] Performing a gain operation on the fourth inclined groove DAC equivalent line based on the fourth average gain difference to obtain a fourth quantitative line;

[0043] A gain operation is performed on the fourth quantitative line based on a preset fourth optimized gain equivalent to obtain the second inner layer standard DAC curve.

[0044] Optionally, further including:

[0045] Before obtaining the outer layer standard DAC curve group based on the scanning results of the plurality of the first simulated defects using the waveguide probe,

[0046] A waveguide probe is axially positioned at a non-welding area of ​​a straight section of an outer end portion of the double-layer bellows of the first test block, and the waveguide probe is circumferentially moved until the first circumferential groove reflection wave heights of all first circumferential grooves, the first through-hole distances between all first through-holes and the waveguide probe, and the first through-hole reflection wave heights are collected;

[0047] The waveguide probe is placed at a non-welding area of ​​the straight section of the outer end of the double-layer corrugated tube of the first test block at the first angle to the axial direction, and the waveguide probe is moved circumferentially until the reflection wave heights of all the first inclined grooves are collected;

[0048] The waveguide probe is placed at the non-welding area of ​​the straight section of the outer end of the double-layer corrugated tube of the first test block at the second angle to the axial direction, and the waveguide probe is moved circumferentially until the distance between all the second inclined grooves and the waveguide probe and the second inclined groove reflection wave height are collected;

[0049] All of the first circumferential groove reflection wave heights, the first through-hole distance, the first through-hole reflection wave height corresponding to the first through-hole distance, the first inclined groove reflection wave height, the second inclined groove distance, and the second inclined groove reflection wave height corresponding to the second inclined groove distance are integrated into the scanning results of the multiple first simulated defects.

[0050] Optionally, further including:

[0051] Before obtaining the inner layer standard DAC curve group based on the scanning results of the plurality of the second simulated defects using the waveguide probe,

[0052] A waveguide probe is axially positioned at the sealing welding area of ​​the straight section of the outer end of the double-layer corrugated tube of the second test block, and the waveguide probe is circumferentially moved until the second circumferential groove reflection wave heights of all second circumferential grooves, the second through-hole distances between all second through-holes and the waveguide probe, and the second through-hole reflection wave heights are collected;

[0053] The waveguide probe is placed at the sealing welding area of ​​the straight section of the outer end of the double-layer corrugated tube of the second test block in a direction forming the third angle with the axial direction, and the waveguide probe is moved circumferentially until the third inclined groove reflection wave height of all third inclined grooves is collected;

[0054] The waveguide probe is placed at the sealing welding area of ​​the straight section of the outer end of the double-layer corrugated tube of the second test block in a direction forming the fourth angle with the axial direction, and the waveguide probe is moved circumferentially until the fourth inclined groove distance and the fourth inclined groove reflection wave height of all the fourth inclined grooves are collected.

[0055] All of the second circumferential groove reflection wave heights, the second through-hole distance, the second through-hole reflection wave height corresponding to the second through-hole distance, the third inclined groove reflection wave height, the fourth inclined groove distance and the fourth inclined groove reflection wave height corresponding to the fourth inclined groove distance are integrated into the scanning results of multiple second simulated defects.

[0056] Optionally, the detecting outer layer defects of the target double-layer corrugated pipe based on a first circumferential scanning result of the outer layer of the target double-layer corrugated pipe using a waveguide probe and the outer layer standard DAC curve group includes:

[0057] According to the first circumferential scanning result, a DAC detection curve of the outer circumferential groove and the through hole and a DAC detection curve of the outer inclined groove are obtained;

[0058] Obtaining a first outer layer standard DAC curve and a second outer layer standard DAC curve according to the outer layer standard DAC curve group;

[0059] Detect the corresponding first outer layer distance between the outer layer circumferential groove and the through-hole DAC detection curve, whose height is greater than the corresponding height in the first outer layer standard DAC curve, and determine the first outer layer defect position based on the first outer layer distance and the corresponding first waveguide probe circumferential position; detect the corresponding second outer layer distance between the outer layer inclined groove DAC detection curve, whose height is greater than the corresponding height in the second outer layer standard DAC curve, and determine the second outer layer defect position based on the second outer layer distance and the corresponding second waveguide probe circumferential position, so as to complete the detection of the outer layer defects of the target double-layer corrugated tube.

[0060] Optionally, the detecting inner layer defects of the target double-layer corrugated pipe based on the second circumferential scanning result of the inner layer of the target double-layer corrugated pipe using the waveguide probe and the inner layer standard DAC curve group includes:

[0061] According to the second circumferential scanning result, a DAC detection curve of the inner layer circumferential groove and through hole and a DAC detection curve of the inner layer inclined groove are obtained;

[0062] Obtaining a first inner layer standard DAC curve and a second inner layer standard DAC curve according to the inner layer standard DAC curve group;

[0063] Detect the corresponding first inner layer distance between the inner layer circumferential groove and the through hole DAC detection curve, whose height is greater than the corresponding height in the first inner layer standard DAC curve, and determine the first inner layer defect position based on the first inner layer distance and the corresponding third waveguide probe circumferential position, detect the corresponding second inner layer distance between the inner layer inclined groove DAC detection curve, whose height is greater than the corresponding height in the second inner layer standard DAC curve, and determine the second inner layer defect position based on the second inner layer distance and the corresponding fourth waveguide probe circumferential position, so as to complete the detection of the inner layer defects of the target double-layer corrugated tube.

[0064] Optionally, the outer circumferential groove and through-hole DAC detection curve is obtained by axially setting the waveguide probe in the non-sealing area of ​​the straight section of the outer end of the target double-layer corrugated tube, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle.

[0065] Optionally, the outer layer inclined groove DAC detection curve is obtained by setting the waveguide probe in the non-welding area of ​​the straight section of the outer layer end of the target double-layer corrugated tube in the direction of the first angle with the axial direction, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle.

[0066] Optionally, the inner circumferential groove and through-hole DAC detection curve is obtained by axially setting the waveguide probe in the sealing area of ​​the straight section of the outer end of the target double-layer corrugated tube, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle.

[0067] Optionally, the inner layer inclined groove DAC detection curve is obtained by setting the waveguide probe in the direction of the third angle with the axial direction in the sealing area of ​​the straight section of the outer end of the target double-layer corrugated tube, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle.

[0068] Optionally, the inner circumferential groove and through-hole DAC detection curve is obtained by axially setting the waveguide probe in the non-sealing area of ​​the straight section of the inner end of the target double-layer corrugated tube, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle.

[0069] Optionally, the inner layer inclined groove DAC detection curve is obtained by setting the waveguide probe in the non-welding area of ​​the straight section of the inner layer end of the target double-layer corrugated tube in the direction of the third angle with the axial direction, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle.

[0070] Optionally, integrating all of the first circumferential groove reflection wave heights, the first through-hole distance, the first through-hole reflection wave height corresponding to the first through-hole distance, the first inclined groove reflection wave height, the second inclined groove distance, and the second inclined groove reflection wave height corresponding to the second inclined groove distance into a scanning result of the plurality of first simulated defects includes:

[0071] Obtaining a corresponding first circumferential groove echo gain according to the first circumferential groove reflection wave height;

[0072] Obtaining a corresponding first through-hole echo gain according to the first through-hole reflection wave height;

[0073] Performing a linear fit between the first through-hole distance and the corresponding first through-hole reflection wave height to obtain a first through-hole DAC equivalent line;

[0074] Obtaining a corresponding first inclined groove echo gain according to the first inclined groove reflection wave height;

[0075] Obtaining a corresponding second inclined groove echo gain according to the second inclined groove reflection wave height;

[0076] Performing a linear fit on the second inclined groove distance and the corresponding second inclined groove reflection wave height to obtain a second inclined groove DAC equivalent line;

[0077] All of the first circumferential groove echo gains, first through-hole echo gains, first through-hole DAC equivalent lines, first inclined groove echo gains, second inclined groove echo gains, and second inclined groove DAC equivalent lines are aggregated to obtain scanning results of the plurality of the first simulated defects.

[0078] Optionally, the step of integrating all of the second circumferential groove reflection wave heights, the second through-hole distance, the second through-hole reflection wave height corresponding to the second through-hole distance, the third inclined groove reflection wave height, the fourth inclined groove distance, and the fourth inclined groove reflection wave height corresponding to the fourth inclined groove distance into a scanning result of the plurality of second simulated defects includes:

[0079] Obtaining a corresponding second circumferential groove echo gain according to the second circumferential groove reflection wave height;

[0080] Obtaining a corresponding second through-hole echo gain according to the second through-hole reflection wave height;

[0081] Performing a linear fit on the second through-hole distance and the corresponding second through-hole reflection wave height to obtain a second through-hole DAC equivalent line;

[0082] Obtaining a corresponding third inclined groove echo gain according to the third inclined groove reflection wave height;

[0083] Obtaining a corresponding fourth inclined groove echo gain according to the fourth inclined groove reflection wave height;

[0084] Performing linear fitting on the fourth inclined groove distance and the corresponding fourth inclined groove reflection wave height to obtain a fourth inclined groove DAC equivalent line;

[0085] All the second circumferential groove echo gains, second through-hole echo gains, second through-hole DAC equivalent lines, third inclined groove echo gains, fourth inclined groove echo gains and fourth inclined groove DAC equivalent lines are aggregated to obtain scanning results of multiple second simulated defects.

[0086] In order to achieve the above object, another aspect of the present invention discloses a test block, including an outer layer test block and an inner layer test block;

[0087] The outer layer inspection test block includes a first test block double-layer bellows and a plurality of first simulated defects provided on the first test block double-layer bellows;

[0088] The first simulated defects include a plurality of first circumferential grooves in a preset first circumferential groove area, a plurality of first through holes in a preset first through hole area, and a plurality of first special grooves in a preset first special groove area, which are respectively arranged on the outer layer of the double-layer bellows of the first test block;

[0089] The inner layer inspection test block includes a second test block double-layer bellows and a plurality of second simulated defects provided on the second test block double-layer bellows;

[0090] The second simulated defects include a plurality of second circumferential grooves in a preset second circumferential groove area, a plurality of second through holes in a preset second through hole area, and a plurality of second special grooves in a preset second special groove area, respectively arranged on the inner layer of the double-layer bellows of the second test block.

[0091] In order to achieve the above objectives, another aspect of the present invention discloses a double-layer corrugated pipe defect detection device based on ultrasonic guided waves, the device comprising:

[0092] A standard DAC curve generation module is configured to obtain an outer layer standard DAC curve group based on scanning results of a plurality of first simulated defects of an outer layer test block using a waveguide probe; and obtain an inner layer standard DAC curve group based on scanning results of a plurality of second simulated defects of an inner layer test block using a waveguide probe; the outer layer test block includes a first test block double-layer bellows and a plurality of first simulated defects provided on the first test block double-layer bellows; wherein the first simulated defects include a plurality of first circumferential grooves in a preset first circumferential groove area, a plurality of first through holes in a preset first through hole area, and a plurality of first special grooves in a preset first special groove area, respectively provided on the outer layer of the first test block double-layer bellows; the inner layer test block includes a second test block double-layer bellows and a plurality of second simulated defects provided on the second test block double-layer bellows; wherein the second simulated defects include a plurality of second circumferential grooves in a preset second circumferential groove area, a plurality of second through holes in a preset second through hole area, and a plurality of second special grooves in a preset second special groove area, respectively provided on the inner layer of the second test block double-layer bellows;

[0093] The bellows defect detection module is used to detect the outer layer defects of the target double-layer corrugated pipe based on the first circumferential scanning result of the outer layer of the target double-layer corrugated pipe using a waveguide probe and the outer layer standard DAC curve group; and to detect the inner layer defects of the target double-layer corrugated pipe based on the second circumferential scanning result of the inner layer of the target double-layer corrugated pipe using a waveguide probe and the inner layer standard DAC curve group.

[0094] The present invention also discloses a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the method described above is implemented when the processor executes the program.

[0095] The present invention also discloses a computer-readable medium on which a computer program is stored. When the program is executed by a processor, the method described above is implemented.

[0096] The test block provided by the present invention makes the outer layer inspection test block include a first test block double-layer bellows and a plurality of first simulated defects arranged on the first test block double-layer bellows; wherein the first simulated defects include a plurality of first circumferential grooves in a preset first circumferential groove area, a plurality of first through holes in a preset first through hole area and a plurality of first special grooves in a preset first special groove area respectively arranged on the outer layer of the first test block double-layer bellows, which can accurately simulate the groove-type defects of the outer layer of an actual double-layer bellows, namely cracks in different directions and through hole-type defects, thereby improving the accuracy of the outer layer standard DAC curve group used for detecting outer layer defects determined based on the outer layer inspection test block in subsequent steps, thereby improving the accuracy of subsequent outer layer defect detection. By making the inner layer inspection test block include a second test block double-layer bellows and a plurality of second simulated defects arranged on the second test block double-layer bellows; wherein the second simulated defects include a plurality of second circumferential grooves in a preset second circumferential groove area, a plurality of second through holes in a preset second through hole area and a plurality of second special grooves in a preset second special groove area respectively arranged on the inner layer of the second test block double-layer bellows, it is possible to accurately simulate the groove-type defects of the inner layer in the actual double-layer bellows, i.e., cracks in different directions and through-hole-type defects, thereby improving the accuracy of the inner layer standard DAC curve group used for detecting inner layer defects determined based on the inner layer inspection test block in subsequent steps, thereby improving the accuracy of subsequent outer layer defect detection.

[0097] The double-layer corrugated pipe defect detection method and detection device based on ultrasonic guided waves provided by the present invention obtain an outer layer standard DAC curve group based on the scanning results of multiple first simulated defects using a guided wave probe, and can quickly and accurately determine the outer layer standard DAC curve group as the standard outer layer detection sensitivity based on various preset outer layer simulated defects without performing complex operations, thereby indirectly reducing the time and difficulty of detecting double-layer corrugated pipe defects and improving the accuracy of detection; obtain an inner layer standard DAC curve group based on the scanning results of multiple second simulated defects using a guided wave probe, and can quickly and accurately determine the inner layer standard DAC curve group as the standard inner layer detection sensitivity based on various preset inner layer simulated defects without performing complex operations, thereby indirectly reducing the time and difficulty of detecting double-layer corrugated pipe defects and improving the accuracy of detection. By detecting the outer layer defects of the target double-layer corrugated pipe based on the first circumferential scanning result of the outer layer of the target double-layer corrugated pipe using a waveguide probe and the outer layer standard DAC curve group, it is possible to quickly and accurately detect the outer layer defects with simple operations without selecting and setting too many waveguide probes and spending more time to determine the specific setting position of the waveguide probe, thereby reducing the time and difficulty of detecting double-layer corrugated pipe defects and improving the accuracy of detection; by detecting the inner layer defects of the target double-layer corrugated pipe based on the second circumferential scanning result of the inner layer of the target double-layer corrugated pipe using a waveguide probe and the inner layer standard DAC curve group, it is possible to quickly and accurately detect the inner layer defects with simple operations without selecting and setting too many waveguide probes and spending more time to determine the specific setting position of the waveguide probe, thereby reducing the time and difficulty of detecting double-layer corrugated pipe defects and improving the accuracy of detection.

[0098] In summary, the double-layer bellows defect detection method, test block and detection device based on ultrasonic guided waves provided by the present invention can reduce the time and difficulty of detecting double-layer bellows defects and improve the accuracy of detection, thereby improving the efficiency of detecting double-layer bellows defects. BRIEF DESCRIPTION OF THE DRAWINGS

[0099] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0100] Figure 1 A schematic flow chart of a method for detecting defects in a double-layer corrugated pipe based on ultrasonic guided waves according to an embodiment of the present invention is shown;

[0101] Figure 2A schematic diagram showing an exemplary outer layer detection test block according to an embodiment of the present invention is shown;

[0102] Figure 3 A schematic diagram showing an optional step of obtaining an outer standard DAC curve group according to an embodiment of the present invention is shown;

[0103] Figure 4 A schematic diagram showing an optional step of obtaining an inner standard DAC curve group according to an embodiment of the present invention is shown;

[0104] Figure 5 A partial cross-sectional view showing an exemplary target double-layer corrugated tube according to an embodiment of the present invention;

[0105] Figure 6 A schematic diagram of a module of a double-layer corrugated pipe defect detection device based on ultrasonic guided waves according to an embodiment of the present invention is shown;

[0106] Figure 7 A schematic diagram showing the structure of a computer device suitable for implementing an embodiment of the present invention is shown.

[0107] Figure markings: 1. First circumferential groove area, 2. First through hole area, 3. First special groove area, 4. First circumferential groove, 5. First through hole, 6. First inclined groove, 7. Second inclined groove, 8. First preset peak, 9. First preset trough, 10. Non-welding area of ​​the straight section of the outer end of the target double-layer corrugated tube, 11. Welding area of ​​the straight section of the outer end of the target double-layer corrugated tube, 12. Non-welding area of ​​the straight section of the inner end of the target double-layer corrugated tube, 13. Inner layer of the target double-layer corrugated tube, 14. Outer layer of the target double-layer corrugated tube, 15. Gap. DETAILED DESCRIPTION

[0108] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not 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 efforts are within the scope of protection of the present invention.

[0109] The terms “first,” “second,” etc. used herein do not particularly refer to an order or sequence, nor are they used to limit the present invention. They are only used to distinguish elements or operations described with the same technical terms.

[0110] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0111] As used herein, "and / or" includes any and all combinations of the items mentioned.

[0112] It should be noted that the acquisition, storage, use, and processing of data in the technical solution of the present invention are in compliance with the relevant provisions of national laws and regulations.

[0113] The embodiment of the present invention discloses a double-layer corrugated pipe defect detection method based on ultrasonic guided waves.

[0114] like Figure 1 As shown, the detection method specifically includes the following steps:

[0115] S101: Based on the scanning results of multiple first simulated defects of the outer layer inspection test block using a waveguide probe, an outer layer standard DAC curve group is obtained; based on the scanning results of multiple second simulated defects of the inner layer inspection test block using a waveguide probe, an inner layer standard DAC curve group is obtained; the outer layer inspection test block includes a first test block double-layer bellows and multiple first simulated defects arranged in the first test block double-layer bellows; wherein the first simulated defects include multiple first circumferential grooves 4 in a preset first circumferential groove area 1, multiple first through holes 5 in a preset first through hole area 2, and multiple first special grooves in a preset first special groove area 3, respectively arranged in the outer layer of the first test block double-layer bellows; the inner layer inspection test block includes a second test block double-layer bellows and multiple second simulated defects arranged in the second test block double-layer bellows; wherein the second simulated defects include multiple second circumferential grooves in a preset second circumferential groove area, multiple second through holes in a preset second through hole area, and multiple second special grooves in a preset second special groove area, respectively arranged in the inner layer of the second test block double-layer bellows.

[0116] S102: Based on the first circumferential scanning result of the outer layer 14 of the target double-layer corrugated pipe using the waveguide probe and the outer layer standard DAC curve group, detect the outer layer defects of the target double-layer corrugated pipe; based on the second circumferential scanning result of the inner layer 13 of the target double-layer corrugated pipe using the waveguide probe and the inner layer standard DAC curve group, detect the inner layer defects of the target double-layer corrugated pipe.

[0117] For example, the material of the first and second test block double-layer bellows can be, but is not limited to, austenitic stainless steel or a material with the same or similar acoustic properties as an actual double-layer bellows workpiece. It should be noted that the materials of the first and second test block double-layer bellows can be determined by those skilled in the art based on actual circumstances, and the above description is merely illustrative and does not constitute a limitation.

[0118] Exemplarily, the first and second test-block double-layer bellows are each composed of two inner and outer sub-bellows layers. The wall thickness of the inner and outer sub-bellows layers is typically determined based on the actual double-layer bellows workpiece, typically but not limited to 1 mm. The thickness of the gap between the inner and outer sub-bellows layers can be, but not limited to, less than or equal to 1 mm. The first and second test-block double-layer bellows have straight end sections at both ends, which can be divided into a welded area and a non-welded area. The welded area can be understood as, but not limited to, the area where the inner and outer sub-bellows layers are welded together. In this welded area, the ends of the two sub-bellows layers are tightly welded together, leaving no gap between them. The non-welded area can be understood as, but not limited to, the area where a gap remains between the inner and outer sub-bellows layers. It should be noted that the specific structures of the first and second test-block double-layer bellows can be determined by those skilled in the art based on actual circumstances. The above description is merely an example and does not constitute a limitation.

[0119] For example, the specific wave number of the first test block double-layer corrugated tube and the second test block double-layer corrugated tube can be determined by those skilled in the art based on actual conditions, and the embodiments of the present invention do not impose any limitation thereto. Preferably, the wave number can be 5, that is, each double-layer corrugated tube has 5 peaks and 4 troughs.

[0120] For example, the waveguide probe may be, but is not limited to, an ultrasonic waveguide probe. The waveguides emitted by the waveguide probe may be, but are not limited to, longitudinal waveguides in the L(0, 2) mode. Waveguides in different modes have different propagation characteristics. It should be noted that the types of waveguide probes and waveguides can be determined by those skilled in the art based on actual conditions. The above description is for illustrative purposes only and does not constitute a limitation thereto.

[0121] Exemplarily, the waveguide frequency and wedge angle of the waveguide probe can be determined based on, but not limited to, the material, thickness and shape of the target double-layer bellows, outer layer inspection test block or inner layer inspection test block. It should be noted that the waveguide frequency and wedge angle of the waveguide probe can be determined by those skilled in the art based on actual conditions. The above description is only an example and does not constitute a limitation to this.

[0122] For example, when inspecting for defects in the outer or inner layers of a target double-layer corrugated pipe, it can also be determined whether the length of the target double-layer corrugated pipe is greater than or equal to 500 mm. If so, waveguide probes are placed at the straight sections on both ends of the target double-layer corrugated pipe to perform a one-shot, one-catch scanning test. Preferably, the waveguide probes on both sides maintain a consistent circumferential position during the scanning process to reduce losses in waveguide transmission and reception, thereby improving the accuracy of waveguide transmission and reception. If not, a waveguide probe can be placed only at the straight sections on either side of the target double-layer corrugated pipe to perform a self-transmitting, self-receiving scanning test. During scanning, the waveguide probe moves along the circumference of the corrugated pipe at the straight sections. Thus, when performing a one-shot, one-catch test, at least two waveguide probes are sufficient, while when performing a self-transmitting, self-receiving test, at least one waveguide probe is sufficient. Therefore, the number of waveguide probes required is very small, and there is no need to overthink the placement of the probes. It should be noted that the specific placement of the waveguide probes can be determined by those skilled in the art based on actual circumstances. The above description is merely an example and does not constitute a limitation.

[0123] Among them, the DAC is the abbreviation of "distance amplitude curve", and the Chinese name of the DAC curve can be but is not limited to "distance-amplitude curve", "distance amplitude correction curve", "distance-amplitude curve" or "distance-amplitude curve", etc.

[0124] For example, Figure 2 As shown, the first circumferential groove area 1, the first through hole area 2 and the first special groove area 3 can be specifically but not limited to be divided into circumferential areas in the circumferential direction, for example, Figure 2 The area between the two dashed lines is the first through-hole area 2, the area below the lower dashed line is the first circumferential groove area 1, and the area above the upper dashed line is the first special groove area 3. The division of the second circumferential groove area, the second through-hole area, and the second special groove area is similar and will not be described in detail here. It should be noted that the specific division of the first circumferential groove area 1, the first through-hole area 2, and the first special groove area 3, as well as the second circumferential groove area, the second through-hole area, and the second special groove area can be determined by those skilled in the art based on actual circumstances. The above description is only an example and does not constitute a limitation.

[0125] The test block provided by the present invention makes the outer layer inspection test block include a first test block double-layer bellows and a plurality of first simulated defects arranged on the first test block double-layer bellows; wherein the first simulated defects include a plurality of first circumferential grooves 4 in a preset first circumferential groove area 1, a plurality of first through holes 5 in a preset first through hole area 2 and a plurality of first special grooves in a preset first special groove area 3 respectively arranged on the outer layer of the first test block double-layer bellows, which can accurately simulate the groove-type defects of the outer layer of the actual double-layer bellows, namely cracks in different directions and through hole-type defects, thereby improving the accuracy of the outer layer standard DAC curve group used for detecting outer layer defects determined based on the outer layer inspection test block in subsequent steps, thereby improving the accuracy of subsequent outer layer defect detection. By making the inner layer inspection test block include a second test block double-layer bellows and a plurality of second simulated defects arranged on the second test block double-layer bellows; wherein the second simulated defects include a plurality of second circumferential grooves in a preset second circumferential groove area, a plurality of second through holes in a preset second through hole area and a plurality of second special grooves in a preset second special groove area respectively arranged on the inner layer of the second test block double-layer bellows, it is possible to accurately simulate the groove-type defects of the inner layer in the actual double-layer bellows, i.e., cracks in different directions and through-hole-type defects, thereby improving the accuracy of the inner layer standard DAC curve group used for detecting inner layer defects determined based on the inner layer inspection test block in subsequent steps, thereby improving the accuracy of subsequent outer layer defect detection.

[0126] The double-layer corrugated pipe defect detection method and detection device based on ultrasonic guided waves provided by the present invention obtain an outer layer standard DAC curve group based on the scanning results of multiple first simulated defects using a guided wave probe, and can quickly and accurately determine the outer layer standard DAC curve group as the standard outer layer detection sensitivity based on various preset outer layer simulated defects without performing complex operations, thereby indirectly reducing the time and difficulty of detecting double-layer corrugated pipe defects and improving the accuracy of detection; obtain an inner layer standard DAC curve group based on the scanning results of multiple second simulated defects using a guided wave probe, and can quickly and accurately determine the inner layer standard DAC curve group as the standard inner layer detection sensitivity based on various preset inner layer simulated defects without performing complex operations, thereby indirectly reducing the time and difficulty of detecting double-layer corrugated pipe defects and improving the accuracy of detection. By detecting the outer layer defects of the target double-layer corrugated pipe based on the first circumferential scanning result of the outer layer 14 of the target double-layer corrugated pipe using a waveguide probe and the outer layer standard DAC curve group, it is possible to quickly and accurately detect the outer layer defects with simple operations without selecting and setting too many waveguide probes and spending more time to determine the specific setting position of the waveguide probe, thereby reducing the time and difficulty of detecting double-layer corrugated pipe defects and improving the accuracy of detection; by detecting the inner layer defects of the target double-layer corrugated pipe based on the second circumferential scanning result of the inner layer 13 of the target double-layer corrugated pipe using a waveguide probe and the inner layer standard DAC curve group, it is possible to quickly and accurately detect the inner layer defects with simple operations without selecting and setting too many waveguide probes and spending more time to determine the specific setting position of the waveguide probe, thereby reducing the time and difficulty of detecting double-layer corrugated pipe defects and improving the accuracy of detection.

[0127] In summary, the double-layer bellows defect detection method, test block and detection device based on ultrasonic guided waves provided by the present invention can reduce the time and difficulty of detecting double-layer bellows defects and improve the accuracy of detection, thereby improving the efficiency of detecting double-layer bellows defects.

[0128] In an optional embodiment, if Figure 2 As shown, the first circumferential grooves 4 are respectively arranged on the inner surface of the plurality of first preset wave crests 8 and the outer surface of the plurality of first preset wave troughs 9 of the outer layer of the double-layer corrugated tube of the first test block.

[0129] Exemplarily, the first circumferential groove 4 can be, but is not limited to, a circumferential rectangular groove whose length is parallel to the circumference. The length, width, depth and other dimensional parameters of the first circumferential groove 4 can be determined by a person skilled in the art according to actual conditions, and the embodiment of the present invention does not impose any restrictions on this. For example, the first circumferential groove 4 is 5 mm long, 0.2 mm wide, and 0.5 mm deep.

[0130] For example, the first preset peak 8 can be determined by a person skilled in the art based on actual conditions, and the present invention does not impose any limitation thereto. Preferably, the first preset peak 8 can be the first, second, or fifth peak counted from either end of the first test block double-layered corrugated tube. The peaks can be, but are not limited to, peaks determined by observing from the outside of the first test block double-layered corrugated tube.

[0131] For example, the first preset trough 9 can be determined by a person skilled in the art based on actual conditions, and the present invention does not impose any limitation thereto. Preferably, the first preset trough 9 can be the first, second, or fourth trough counted from either end of the first test block double-layered corrugated tube. The troughs can be, but are not limited to, troughs determined by observing from the outside of the first test block double-layered corrugated tube.

[0132] The inner surface specifically refers to the surface of a layer of the bellows that is closer to the axis in the radial direction of the cross section of the bellows, and the outer surface specifically refers to the surface of the layer that is farther away from the axis in the radial direction of the cross section of the bellows.

[0133] By arranging the first circumferential grooves 4 on the inner surfaces of the multiple first preset peaks 8 and the outer surfaces of the multiple first preset troughs 9 of the outer layer of the double-layer bellows of the first test block respectively, the number of first circumferential grooves 4 can be sufficient, and they can be distributed in acoustically representative places on the outer layer of the double-layer bellows of the first test block, so as to more comprehensively simulate the circumferential crack defects of the outer layer of the double-layer bellows, thereby improving the accuracy of the standard DAC curve for detection generated based on the first circumferential grooves 4 in subsequent steps, thereby indirectly improving the detection accuracy of the target double-layer bellows.

[0134] In an optional embodiment, if Figure 2 As shown, the first through holes 5 are respectively arranged on the plurality of first preset wave crests 8 and the plurality of first preset wave troughs 9 of the outer layer of the double-layer corrugated tube of the first test block.

[0135] Exemplarily, the first through hole 5 can be but not limited to a circular through hole. The size of the first through hole 5 can be determined by a person skilled in the art according to actual conditions, and the embodiment of the present invention does not limit this. For example, the first through hole 5 can be but not limited to a Φ3 through hole (i.e., a circular through hole with a diameter of 3 mm).

[0136] For example, the first preset peak 8 can be determined by those skilled in the art according to actual conditions, and the embodiments of the present invention do not limit this. Preferably, the first preset peak 8 can be the first, second, or fifth peak counted from either side end of the first test block double-layer corrugated tube.

[0137] For example, the first preset trough 9 can be determined by a person skilled in the art according to actual conditions, and the embodiments of the present invention do not limit this. Preferably, the first preset trough 9 can be the 1st, 2nd, or 4th trough counted from either side end of the first test block double-layer corrugated tube.

[0138] By respectively arranging the first through holes 5 at the plurality of first preset peaks 8 and the plurality of first preset troughs 9 of the outer layer of the double-layer bellows of the first test block, the number of first through holes 5 can be sufficient and they can be distributed in acoustically representative places on the outer layer of the double-layer bellows of the first test block, thereby being able to more comprehensively simulate the pitting corrosion and perforation defects of the outer layer of the double-layer bellows, thereby improving the accuracy of the standard DAC curve for detection generated based on the first through holes 5 in subsequent steps, thereby indirectly improving the detection accuracy of the target double-layer bellows.

[0139] In an optional embodiment, if Figure 2 As shown, the first special grooves include a plurality of first inclined grooves 6 forming a first angle with the circumferential direction and a plurality of second inclined grooves 7 forming a second angle with the circumferential direction; wherein the first angle and the second angle are acute angles.

[0140] For example, the first angle may be, but not limited to, 45°, and the second angle may be, but not limited to, 60°.

[0141] By making the first special groove include multiple first inclined grooves 6 with a first angle to the circumferential direction and multiple second inclined grooves 7 with a second angle to the circumferential direction, it is possible to simulate oblique crack defects at different angles in the outer layer of the double-layer corrugated pipe, thereby improving the comprehensiveness and accuracy of the simulation of oblique crack defects in the outer layer of the double-layer corrugated pipe, and further improving the accuracy of the standard DAC curve for detection generated based on the first inclined grooves 6 and the second inclined grooves 7 in subsequent steps, thereby indirectly improving the detection accuracy of the target double-layer corrugated pipe.

[0142] In an optional embodiment, if Figure 2 As shown, the first inclined grooves 6 are respectively arranged on the inner surfaces of the multiple first preset peaks 8 and the outer surfaces of the multiple first preset troughs 9 of the outer layer of the double-layer corrugated tube of the first test block; the second inclined grooves 7 are respectively arranged on the inner surfaces of the multiple first preset peaks 8 and the outer surfaces of the multiple first preset troughs 9 of the outer layer of the double-layer corrugated tube of the first test block.

[0143] Exemplarily, the first inclined groove 6 and the second inclined groove 7 can be, but are not limited to, rectangular grooves whose lengths form corresponding angles with the circumferential direction. The length, width, depth and other dimensional parameters of the first inclined groove 6 and the second inclined groove 7 can be determined by those skilled in the art according to actual conditions, and the embodiment of the present invention does not impose any restrictions on this. For example, the length of the first inclined groove 6 and the second inclined groove 7 is 5 mm, the width is 0.2 mm, and the depth is 0.5 mm.

[0144] For example, the first preset peak 8 can be determined by those skilled in the art according to actual conditions, and the embodiments of the present invention do not limit this. Preferably, the first preset peak 8 can be the first, second, or fifth peak counted from either side end of the first test block double-layer corrugated tube.

[0145] For example, the first preset trough 9 can be determined by a person skilled in the art according to actual conditions, and the embodiments of the present invention do not limit this. Preferably, the first preset trough 9 can be the 1st, 2nd, or 4th trough counted from either side end of the first test block double-layer corrugated tube.

[0146] By respectively arranging the first inclined grooves 6 on the inner surfaces of the plurality of first preset peaks 8 and the outer surfaces of the plurality of first preset troughs 9 of the outer layer of the double-layer bellows of the first test block, and respectively arranging the second inclined grooves 7 on the inner surfaces of the plurality of first preset peaks 8 and the outer surfaces of the plurality of first preset troughs 9 of the outer layer of the double-layer bellows of the first test block, the number of the first inclined grooves 6 and the second inclined grooves 7 can be sufficient, and they can be distributed in acoustically representative places on the outer layer of the double-layer bellows of the first test block, so as to more comprehensively simulate the inclined crack defects of the outer layer of the double-layer bellows, thereby further improving the accuracy of the standard DAC curve for detection generated based on the first inclined grooves 6 and the second inclined grooves 7 in subsequent steps, thereby indirectly improving the detection accuracy of the target double-layer bellows.

[0147] In an optional embodiment, the circumferential spacing distance between multiple first simulated defects arranged at the same wave crest of the first test block double-layer corrugated tube is greater than the preset first defect spacing distance; the circumferential spacing distance between multiple first simulated defects arranged at the same wave trough of the first test block double-layer corrugated tube is greater than the first defect spacing distance.

[0148] For example, the first defect spacing distance can be determined by those skilled in the art according to actual conditions, and the present invention does not limit this. Preferably, the first defect spacing distance is 15 mm.

[0149] By making the circumferential spacing distance between multiple first simulated defects set at the same wave crest of the first test block double-layer corrugated tube greater than the preset first defect spacing distance, and the circumferential spacing distance between multiple first simulated defects set at the same wave trough of the first test block double-layer corrugated tube greater than the first defect spacing distance, when the multiple first simulated defects are scanned with a waveguide probe, the multiple echoes generated by the waveguide probe's waveguide due to the first simulated defects will not interfere with each other, thereby improving the accuracy of the outer layer standard DAC curve group obtained as the outer layer standard sensitivity, and further improving the accuracy of detecting the outer layer defects of the target double-layer corrugated tube in subsequent steps.

[0150] In an optional embodiment, the second circumferential grooves are respectively arranged on the inner surface of multiple second preset peaks and the outer surface of multiple second preset troughs of the inner layer of the double-layer corrugated tube of the second test block.

[0151] Exemplarily, the second circumferential groove may be, but is not limited to, a circumferential rectangular groove whose length is parallel to the circumference. The length, width, depth and other dimensional parameters of the second circumferential groove may be determined by a person skilled in the art according to actual conditions, and the embodiment of the present invention does not impose any restrictions on this. For example, the length of the second circumferential groove is 5 mm, the width is 0.2 mm, and the depth is 0.5 mm.

[0152] For example, the second preset peak can be determined by a person skilled in the art based on actual conditions, and the present invention does not impose any limitation thereto. Preferably, the second preset peak can be the first, second, or fifth peak counted from either end of the second test block double-layered corrugated tube. The peak can be, but is not limited to, a peak determined by observing from the outside of the second test block double-layered corrugated tube.

[0153] For example, the second preset trough can be determined by a person skilled in the art based on actual conditions, and the present invention does not impose any limitation thereto. Preferably, the second preset trough can be the first, second, or fourth trough counted from either end of the second test block double-layered corrugated tube. The trough can be, but is not limited to, a trough determined by observing from the outside of the second test block double-layered corrugated tube.

[0154] The inner surface specifically refers to the surface of a layer of the bellows that is closer to the axis in the radial direction of the cross section of the bellows, and the outer surface specifically refers to the surface of the layer that is farther away from the axis in the radial direction of the cross section of the bellows.

[0155] By arranging the second circumferential grooves on the inner surface of multiple second preset peaks and the outer surface of multiple second preset troughs of the inner layer of the double-layer bellows of the second test block respectively, the number of second circumferential grooves can be sufficient and distributed in acoustically representative places of the inner layer of the double-layer bellows of the second test block, thereby being able to more comprehensively simulate the circumferential crack defects of the inner layer of the double-layer bellows, thereby improving the accuracy of the standard DAC curve for detection generated based on the second circumferential grooves in subsequent steps, thereby indirectly improving the detection accuracy of the target double-layer bellows.

[0156] In an optional embodiment, the second through holes are respectively provided at a plurality of the second preset wave crests and a plurality of the second preset wave troughs of the inner layer of the double-layer corrugated tube of the second test block.

[0157] Exemplarily, the second through hole may be but is not limited to a circular through hole. The size of the second through hole may be determined by a person skilled in the art according to actual conditions, and the embodiment of the present invention does not impose any restrictions on this. For example, the second through hole may be but is not limited to a Φ3 through hole (i.e., a circular through hole with a diameter of 3 mm).

[0158] For example, the second preset peak can be determined by a person skilled in the art according to actual conditions, and the embodiments of the present invention do not limit this. Preferably, the second preset peak can be the first, second, or fifth peak counted from either end of the second test block double-layer corrugated tube.

[0159] For example, the second preset trough can be determined by a person skilled in the art according to actual conditions, and the embodiments of the present invention do not limit this. Preferably, the second preset trough can be the first, second, or fourth trough counted from either side end of the second test block double-layer corrugated tube.

[0160] By respectively arranging the second through holes at the multiple second preset peaks and multiple second preset troughs of the inner layer of the double-layer bellows of the second test block, the number of second through holes can be sufficient and they can be distributed in acoustically representative places of the inner layer of the double-layer bellows of the second test block, thereby being able to more comprehensively simulate the pitting corrosion and perforation defects of the inner layer of the double-layer bellows, thereby improving the accuracy of the standard DAC curve for detection generated based on the second through holes in subsequent steps, thereby indirectly improving the detection accuracy of the target double-layer bellows.

[0161] In an optional embodiment, the second special grooves include a plurality of third inclined grooves forming a third angle with the circumferential direction and a plurality of fourth inclined grooves forming a fourth angle with the circumferential direction; wherein the third angle and the fourth angle are acute angles.

[0162] For example, the third angle may be, but not limited to, 45°, and the fourth angle may be, but not limited to, 60°.

[0163] By making the second special groove include multiple third inclined grooves with a third angle to the circumferential direction and multiple fourth inclined grooves with a fourth angle to the circumferential direction, it is possible to simulate oblique crack defects at different angles in the inner layer of the double-layer corrugated tube, thereby improving the comprehensiveness and accuracy of the simulation of oblique crack defects in the inner layer of the double-layer corrugated tube, and further improving the accuracy of the standard DAC curve for detection generated based on the third inclined groove and the fourth inclined groove in the subsequent steps, thereby indirectly improving the detection accuracy of the target double-layer corrugated tube.

[0164] In an optional embodiment, the third inclined groove is respectively arranged on the inner surface of the multiple second preset peaks and the outer surface of the multiple second preset troughs of the inner layer of the double-layer corrugated tube of the second test block; the fourth inclined groove is respectively arranged on the inner surface of the multiple second preset peaks and the outer surface of the multiple second preset troughs of the inner layer of the double-layer corrugated tube of the second test block.

[0165] Exemplarily, the third inclined groove and the fourth inclined groove can be, but are not limited to, rectangular grooves whose lengths form corresponding angles with the circumferential direction. The length, width, depth and other dimensional parameters of the third inclined groove and the fourth inclined groove can be determined by those skilled in the art according to actual conditions. The embodiment of the present invention does not impose any restrictions on this. For example, the length of the third inclined groove and the fourth inclined groove is 5 mm, the width is 0.2 mm, and the depth is 0.5 mm.

[0166] For example, the second preset peak can be determined by a person skilled in the art according to actual conditions, and the embodiments of the present invention do not limit this. Preferably, the second preset peak can be the first, second, or fifth peak counted from either end of the second test block double-layer corrugated tube.

[0167] For example, the second preset trough can be determined by a person skilled in the art according to actual conditions, and the embodiments of the present invention do not limit this. Preferably, the second preset trough can be the first, second, or fourth trough counted from either side end of the second test block double-layer corrugated tube.

[0168] By respectively arranging the third inclined groove on the inner surface of the plurality of second preset peaks and the outer surface of the plurality of second preset troughs of the inner layer of the double-layer bellows of the second test block, and respectively arranging the fourth inclined groove on the inner surface of the plurality of second preset peaks and the outer surface of the plurality of second preset troughs of the inner layer of the double-layer bellows of the second test block, the number of the third inclined grooves and the fourth inclined grooves can be sufficient, and they can be distributed in acoustically representative places of the inner layer of the double-layer bellows of the second test block, so as to more comprehensively simulate the inclined crack defects of the inner layer of the double-layer bellows, thereby further improving the accuracy of the standard DAC curve for detection generated based on the third inclined groove and the fourth inclined groove in subsequent steps, thereby indirectly improving the detection accuracy of the target double-layer bellows.

[0169] In an optional embodiment, the circumferential spacing distance between multiple second simulated defects set at the same wave crest of the second test block double-layer corrugated tube is greater than the preset second defect spacing distance; the circumferential spacing distance between multiple second simulated defects set at the same wave trough of the second test block double-layer corrugated tube is greater than the second defect spacing distance.

[0170] For example, the second defect spacing distance can be determined by those skilled in the art according to actual conditions, and the present invention does not limit this. Preferably, the second defect spacing distance is 15 mm.

[0171] By making the circumferential spacing distance between multiple second simulated defects set at the same wave crest of the second test block double-layer corrugated tube greater than the preset second defect spacing distance, and the circumferential spacing distance between multiple second simulated defects set at the same wave trough of the second test block double-layer corrugated tube greater than the second defect spacing distance, when the multiple second simulated defects are scanned with a waveguide probe, the multiple echoes generated by the waveguide probe's waveguide due to the second simulated defects will not interfere with each other, thereby improving the accuracy of the inner layer standard DAC curve group obtained as the inner layer standard sensitivity, and further improving the accuracy of detecting the inner layer defects of the target double-layer corrugated tube in subsequent steps.

[0172] In an optional embodiment, if Figure 3 As shown, the method of obtaining the outer layer standard DAC curve group based on the scanning results of the plurality of the first simulated defects using a waveguide probe includes the following steps:

[0173] S301: Based on the scanning results of the plurality of first simulated defects, the first circumferential groove echo gain corresponding to each first circumferential groove 4, the first through-hole DAC equivalent line, the first through-hole echo gain corresponding to each first through-hole 5, the first inclined groove echo gain corresponding to each first inclined groove 6, the second inclined groove DAC equivalent line and the second inclined groove echo gain corresponding to each second inclined groove 7 are obtained.

[0174] S302: Obtain a first outer layer standard DAC curve according to the first circumferential groove echo gain, the first through-hole DAC equivalent line, and the first through-hole echo gain.

[0175] S303: Obtain a second outer layer standard DAC curve according to the first inclined groove echo gain, the second inclined groove DAC equivalent line and the second inclined groove echo gain.

[0176] S304: Clustering the first outer standard DAC curve and the second outer standard DAC curve to obtain an outer standard DAC curve group.

[0177] Exemplarily, when scanning the first simulated defect, the orientation of the guided wave probe may be adjusted so that the emitted guided wave acoustic beam can be aligned with and hit the first simulated defect.

[0178] For example, the first circumferential groove echo gain can be understood as, but not limited to, an echo amplitude adjustment corresponding to the echo generated by the waveguide probe upon encountering the first circumferential groove 4. The echo amplitude adjustment is a detection parameter of the digital ultrasonic flaw detector corresponding to the waveguide probe. The first through-hole echo gain, the first inclined groove echo gain, and the second inclined groove echo gain are similarly understood and are not further described here.

[0179] Exemplarily, the first through-hole DAC equivalent line may be generated by, but not limited to, the following steps:

[0180] The distance and amplitude are respectively used as the two-dimensional parameters of a preset DAC two-dimensional coordinate system, and the distances between all the scanned first through holes 5 and the waveguide probe and the corresponding reflected wave heights are obtained. The maximum wave height of the reflected wave height is adjusted to 80% of the screen height (the other reflected wave heights are also automatically adjusted proportionally or manually adjusted proportionally). Based on the distance between each first through hole 5 and the waveguide probe and the corresponding adjusted wave height, multiple corresponding points are determined in the DAC two-dimensional coordinate system, and the corresponding first through hole DAC equivalent lines are determined based on these points, wherein the first through hole DAC equivalent lines can be generated based on these points by, but not limited to, linear fitting.

[0181] It should be noted that the specific method for generating the first through-hole DAC equivalent line can be determined by those skilled in the art based on actual circumstances. The above description is merely an example and does not constitute a limitation. The method for generating the second inclined groove DAC equivalent line is similar to that for generating the first through-hole DAC equivalent line and will not be further described here.

[0182] Exemplarily, since the scanning results of multiple first simulated defects include the first circumferential groove echo gain corresponding to each first circumferential groove 4, the first through-hole DAC equivalent line, the first through-hole echo gain corresponding to each first through-hole 5, the first inclined groove echo gain corresponding to each first inclined groove 6, the second inclined groove DAC equivalent line and the second inclined groove echo gain corresponding to each second inclined groove 7, the first circumferential groove echo gain corresponding to each first circumferential groove 4, the first through-hole DAC equivalent line, the first through-hole echo gain corresponding to each first through-hole 5, the first inclined groove echo gain corresponding to each first inclined groove 6, the second inclined groove DAC equivalent line and the second inclined groove echo gain corresponding to each second inclined groove 7 can be obtained directly based on the scanning results of multiple first simulated defects.

[0183] Through steps S301 to S304, the acoustic wave characteristics of the first circumferential groove 4 and the first through-hole 5 are combined to determine a first outer layer standard DAC curve that can be used to detect both outer layer circumferential crack defects and outer layer perforation defects. This improves the detection accuracy of the first outer layer standard DAC curve and enables this standard curve to detect both outer layer circumferential crack defects and outer layer perforation defects. Furthermore, the acoustic wave characteristics of the first oblique groove 6 and the second oblique groove 7 are combined to determine a second outer layer standard DAC curve that can be used to detect outer layer crack defects with multiple oblique directions. This improves the detection accuracy of the second outer layer standard DAC curve and enables this standard curve to detect outer layer crack defects with multiple oblique directions. Therefore, while improving detection accuracy, the number of standard curves in the outer layer standard DAC curve group can be minimized, thereby indirectly reducing the number of tests performed in subsequent steps to detect outer layer defects of the bellows, and thereby indirectly improving the detection efficiency of outer layer defects of the bellows.

[0184] In an optional embodiment, obtaining the first outer layer standard DAC curve according to the first circumferential groove echo gain, the first through-hole DAC equivalent line and the first through-hole echo gain includes:

[0185] subtracting the corresponding first through-hole echo gain from each first circumferential groove echo gain to obtain a plurality of first gain differences, and taking an average of the plurality of first gain differences as a first average gain difference;

[0186] Performing a gain operation on the first through-hole DAC equivalent line based on the first average gain difference to obtain a first quantitative line;

[0187] A gain operation is performed on the first quantitative line based on a preset first optimized gain equivalent to obtain the first outer standard DAC curve.

[0188] Exemplarily, the corresponding first through-hole echo gain may be, but is not limited to, the echo gain of the first through-hole 5 disposed at the same crest or trough where the first circumferential groove 4 is located.

[0189] For example, performing a gain operation on the first through-hole DAC equivalent line based on the first average gain difference to obtain the first quantitative line may be, but is not limited to, performing a gain operation on the first through-hole DAC equivalent line by the first average gain difference to obtain the first quantitative line. For example, if the first average gain difference is 2 dB, then performing a gain operation on the first through-hole DAC equivalent line by 2 dB to obtain the first quantitative line. It should be noted that the specific implementation of performing a gain operation on the first through-hole DAC equivalent line based on the first average gain difference to obtain the first quantitative line can be determined by those skilled in the art based on actual circumstances. The above description is merely an example and does not constitute a limitation.

[0190] Exemplarily, the gain operation on the first quantitative line based on the preset first optimized gain equivalent to obtain the first outer standard DAC curve can be, but is not limited to, the first quantitative line gain is increased by the first optimized gain equivalent to obtain the first outer standard DAC curve. For example, if the first optimized gain equivalent is 6db, the first quantitative line is increased by 6db to obtain the first outer standard DAC curve. The first optimized gain equivalent can be determined by those skilled in the art according to actual conditions, and the embodiment of the present invention does not limit this. Preferably, the first optimized gain equivalent can be 6db. It should be noted that the specific implementation method of performing the gain operation on the first quantitative line based on the preset first optimized gain equivalent to obtain the first outer standard DAC curve can be determined by those skilled in the art according to actual conditions. The above description is only an example and does not constitute a limitation.

[0191] Through the above steps, the comprehensive influence of the first through hole 5 and the first circumferential groove 4 on the relevant gain and waveguide characteristics can be better considered based on the relevant flaw detection principles, thereby improving the accuracy of the obtained first quantitative line, and further gaining the first quantitative line to obtain the first outer layer standard DAC curve. It is possible to adjust the detection sensitivity when detecting defects using the first outer layer standard DAC curve according to actual needs, thereby better meeting relevant detection needs and improving detection accuracy.

[0192] In an optional embodiment, obtaining a second outer layer standard DAC curve according to the first inclined groove echo gain, the second inclined groove DAC equivalent line and the second inclined groove echo gain includes:

[0193] subtracting the corresponding second inclined groove echo gain from each first inclined groove echo gain to obtain a plurality of second gain differences, and taking an average of the plurality of second gain differences as a second average gain difference;

[0194] Performing a gain operation on the second inclined groove DAC equivalent line based on the second average gain difference to obtain a second quantitative line;

[0195] A gain operation is performed on the second quantitative line based on a preset second optimized gain equivalent to obtain the second outer layer standard DAC curve.

[0196] For example, the corresponding echo gain of the second oblique groove may be, but is not limited to, the echo gain of the second oblique groove 7 provided at the same crest or trough as the first oblique groove 6 .

[0197] For example, performing a gain operation on the second inclined groove DAC equivalent line based on the second average gain difference to obtain the second quantitative line may be, but is not limited to, performing a gain operation on the second inclined groove DAC equivalent line by the second average gain difference to obtain the second quantitative line. For example, if the second average gain difference is 3 dB, then performing a gain operation on the second inclined groove DAC equivalent line by 3 dB to obtain the second quantitative line. It should be noted that the specific implementation of performing a gain operation on the second inclined groove DAC equivalent line based on the second average gain difference to obtain the second quantitative line can be determined by those skilled in the art based on actual circumstances. The above description is merely an example and does not constitute a limitation.

[0198] Exemplarily, the gain operation on the second quantitative line based on the preset second optimized gain equivalent to obtain the second outer standard DAC curve can be, but is not limited to, the second quantitative line gain is increased by the second optimized gain equivalent to obtain the second outer standard DAC curve. For example, if the second optimized gain equivalent is 6db, the second quantitative line is increased by 6db to obtain the second outer standard DAC curve. The second optimized gain equivalent can be determined by those skilled in the art according to actual conditions, and the embodiment of the present invention does not limit this. Preferably, the second optimized gain equivalent can be 6db. It should be noted that the specific implementation method of performing the gain operation on the second quantitative line based on the preset second optimized gain equivalent to obtain the second outer standard DAC curve can be determined by those skilled in the art according to actual conditions. The above description is only an example and does not constitute a limitation.

[0199] Through the above steps, the comprehensive influence of the first inclined groove 6 and the second inclined groove 7 on the relevant gain and waveguide characteristics can be better considered based on the relevant flaw detection principles, thereby improving the accuracy of the second quantitative line obtained, and further gaining the second quantitative line to obtain the second outer layer standard DAC curve. It is possible to adjust the detection sensitivity when detecting defects using the second outer layer standard DAC curve according to actual needs, thereby better meeting relevant detection needs and improving detection accuracy.

[0200] In an optional embodiment, if Figure 4 As shown, the method of obtaining the inner layer standard DAC curve group based on the scanning results of the plurality of second simulated defects using a waveguide probe includes the following steps:

[0201] S401: Based on the scanning results of multiple second simulated defects, the second circumferential groove echo gain corresponding to each second circumferential groove, the second through-hole DAC equivalent line, the second through-hole echo gain corresponding to each second through-hole, the third inclined groove echo gain corresponding to each third inclined groove, the fourth inclined groove DAC equivalent line and the fourth inclined groove echo gain corresponding to each fourth inclined groove are obtained.

[0202] S402: Obtain a first inner layer standard DAC curve according to the second circumferential groove echo gain, the second through-hole DAC equivalent line, and the second through-hole echo gain.

[0203] S403: Obtain a second inner layer standard DAC curve according to the third inclined groove echo gain, the fourth inclined groove DAC equivalent line and the fourth inclined groove echo gain.

[0204] S404: Clustering the first inner standard DAC curve and the second inner standard DAC curve to obtain an inner standard DAC curve group.

[0205] Exemplarily, when scanning the second simulated defect, the direction of the guided wave probe can be adjusted so that the emitted guided wave acoustic beam can be aimed at and hit the second simulated defect.

[0206] For example, the second circumferential groove echo gain can be understood as, but not limited to, an echo amplitude adjustment corresponding to the echo generated by the waveguide probe upon encountering the second circumferential groove. The echo amplitude adjustment is a detection parameter of the digital ultrasonic flaw detector corresponding to the waveguide probe. The second through-hole echo gain, the third inclined groove echo gain, and the fourth inclined groove echo gain are similarly defined and are not further described here.

[0207] Exemplarily, the second through-hole DAC equivalent line may be generated by, but not limited to, the following steps:

[0208] The distance and amplitude are respectively used as the two-dimensional parameters of a preset DAC two-dimensional coordinate system, and the distances between all the scanned second through holes and the waveguide probe and the corresponding reflected wave heights are obtained. The maximum wave height of the reflected wave is adjusted to 80% of the screen height (the other reflected wave heights are also automatically adjusted proportionally or manually adjusted proportionally). Based on the distance between each second through hole and the waveguide probe and the corresponding adjusted wave height, multiple corresponding points are determined in the DAC two-dimensional coordinate system, and the corresponding second through hole DAC equivalent lines are determined based on these points, wherein the second through hole DAC equivalent lines can be generated based on these points by, but not limited to, linear fitting.

[0209] It should be noted that the specific method for generating the second through-hole DAC equivalent line can be determined by those skilled in the art based on actual circumstances. The above description is merely an example and does not constitute a limitation. The method for generating the fourth inclined groove DAC equivalent line is similar to that for generating the second through-hole DAC equivalent line and will not be further described here.

[0210] Exemplarily, since the scanning results of multiple second-simulated defects include the second circumferential groove echo gain corresponding to each second circumferential groove, the second through-hole DAC equivalent line, the second through-hole echo gain corresponding to each second through-hole, the third inclined groove echo gain corresponding to each third inclined groove, the fourth inclined groove DAC equivalent line and the fourth inclined groove echo gain corresponding to each fourth inclined groove, the second circumferential groove echo gain corresponding to each second circumferential groove, the second through-hole DAC equivalent line, the second through-hole echo gain corresponding to each second through-hole, the third inclined groove echo gain corresponding to each third inclined groove, the fourth inclined groove DAC equivalent line and the fourth inclined groove echo gain corresponding to each fourth inclined groove can be obtained directly based on the scanning results of multiple second-simulated defects.

[0211] Through steps S401 to S404, the acoustic wave characteristics of the second circumferential groove and the second through-hole are combined to determine a first inner layer standard DAC curve that can be used to detect both inner layer circumferential crack defects and inner layer perforation defects. This improves the detection accuracy of the first inner layer standard DAC curve and further enables this standard curve to detect both inner layer circumferential cracks and inner layer perforations. Furthermore, the acoustic wave characteristics of the third and fourth oblique grooves are combined to determine a second inner layer standard DAC curve that can be used to detect inner layer crack defects with multiple oblique directions. This improves the detection accuracy of the second inner layer standard DAC curve and further enables this standard curve to detect inner layer crack defects with multiple oblique directions. Therefore, while improving detection accuracy, the number of standard curves in the inner layer standard DAC curve set can be minimized, thereby indirectly reducing the number of tests performed in subsequent steps to detect inner layer defects in the bellows, and thus indirectly improving the detection efficiency of inner layer defects in the bellows.

[0212] In an optional embodiment, obtaining the first inner layer standard DAC curve according to the second circumferential groove echo gain, the second through-hole DAC equivalent line and the second through-hole echo gain includes:

[0213] Subtracting the corresponding second through-hole echo gain from each second circumferential groove echo gain to obtain a plurality of third gain differences, and taking an average of the plurality of third gain differences as a third average gain difference;

[0214] Performing a gain operation on the second through-hole DAC equivalent line based on the third average gain difference to obtain a third quantitative line;

[0215] A gain operation is performed on the third quantitative line based on a preset third optimized gain equivalent to obtain the first inner layer standard DAC curve.

[0216] Exemplarily, the corresponding echo gain of the second through-hole may be, but is not limited to, the echo gain of the second through-hole disposed at the same crest or trough where the second circumferential groove is located.

[0217] For example, performing a gain operation on the second through-hole DAC equivalent line based on the third average gain difference to obtain the third quantitative line may be, but is not limited to, performing a gain operation on the second through-hole DAC equivalent line by the third average gain difference to obtain the second quantitative line. For example, if the third average gain difference is 2.5 dB, then performing a gain operation on the second through-hole DAC equivalent line by 2.5 dB to obtain the third quantitative line. It should be noted that the specific implementation of performing a gain operation on the second through-hole DAC equivalent line based on the third average gain difference to obtain the third quantitative line can be determined by those skilled in the art based on actual circumstances. The above description is merely an example and does not constitute a limitation.

[0218] Exemplarily, the gain operation on the third quantitative line based on the preset third optimized gain equivalent to obtain the first inner standard DAC curve can be, but is not limited to, the third quantitative line gain by the third optimized gain equivalent to obtain the first inner standard DAC curve. For example, if the third optimized gain equivalent is 6db, the third quantitative line gain by 6db is obtained to obtain the first inner standard DAC curve. The third optimized gain equivalent can be determined by those skilled in the art according to actual conditions, and the embodiment of the present invention does not limit this. Preferably, the third optimized gain equivalent can be 6db. It should be noted that the specific implementation method of performing the gain operation on the third quantitative line based on the preset third optimized gain equivalent to obtain the first inner standard DAC curve can be determined by those skilled in the art according to actual conditions. The above description is only an example and does not constitute a limitation to this.

[0219] Through the above steps, the comprehensive influence of the second through hole and the second circumferential groove on the relevant gain and waveguide characteristics can be better considered based on the relevant flaw detection principles, thereby improving the accuracy of the third quantitative line obtained, and further gaining the third quantitative line to obtain the first inner layer standard DAC curve. It is possible to adjust the detection sensitivity when detecting defects using the first inner layer standard DAC curve according to actual needs, thereby better meeting relevant detection needs and improving detection accuracy.

[0220] In an optional embodiment, obtaining a second inner layer standard DAC curve according to the third inclined groove echo gain, the fourth inclined groove DAC equivalent line and the fourth inclined groove echo gain includes:

[0221] subtracting the corresponding fourth inclined groove echo gain from each third inclined groove echo gain to obtain a plurality of fourth gain differences, and taking an average of the plurality of fourth gain differences as a fourth average gain difference;

[0222] Performing a gain operation on the fourth inclined groove DAC equivalent line based on the fourth average gain difference to obtain a fourth quantitative line;

[0223] A gain operation is performed on the fourth quantitative line based on a preset fourth optimized gain equivalent to obtain the second inner layer standard DAC curve.

[0224] Illustratively, the corresponding echo gain of the fourth inclined groove may be, but is not limited to, the echo gain of a fourth inclined groove located at the same crest or trough as the third inclined groove.

[0225] For example, performing a gain operation on the fourth inclined groove DAC equivalent line based on the fourth average gain difference to obtain a fourth quantitative line may be, but is not limited to, performing a gain operation on the fourth inclined groove DAC equivalent line by the fourth average gain difference to obtain the fourth quantitative line. For example, if the fourth average gain difference is 3.5 dB, then performing a gain operation on the fourth inclined groove DAC equivalent line by 3.5 dB to obtain the fourth quantitative line. It should be noted that the specific implementation method for performing a gain operation on the fourth inclined groove DAC equivalent line based on the fourth average gain difference to obtain the fourth quantitative line can be determined by those skilled in the art based on actual circumstances. The above description is merely an example and does not constitute a limitation.

[0226] Exemplarily, the gain operation of the fourth quantitative line based on the preset fourth optimized gain equivalent to obtain the second inner standard DAC curve can be, but is not limited to, the gain of the fourth quantitative line by the fourth optimized gain equivalent to obtain the second inner standard DAC curve. For example, if the fourth optimized gain equivalent is 6db, the gain of the fourth quantitative line by 6db is obtained to obtain the second inner standard DAC curve. The fourth optimized gain equivalent can be determined by those skilled in the art according to actual conditions, and the embodiment of the present invention does not limit this. Preferably, the fourth optimized gain equivalent can be 6db. It should be noted that the specific implementation method of performing the gain operation on the fourth quantitative line based on the preset fourth optimized gain equivalent to obtain the second inner standard DAC curve can be determined by those skilled in the art according to actual conditions. The above description is only an example and does not constitute a limitation to this.

[0227] Through the above steps, the comprehensive influence of the third inclined groove and the fourth inclined groove on the relevant gain and waveguide characteristics can be better considered based on the relevant flaw detection principles, thereby improving the accuracy of the fourth quantitative line obtained, and further gaining the fourth quantitative line to obtain the second inner layer standard DAC curve. It is possible to adjust the detection sensitivity when detecting defects using the second inner layer standard DAC curve according to actual needs, thereby better meeting relevant detection needs and improving detection accuracy.

[0228] In an optional embodiment, further comprising:

[0229] Before obtaining the outer layer standard DAC curve group based on the scanning results of the plurality of the first simulated defects using the waveguide probe,

[0230] A waveguide probe is axially set at the non-welding area of ​​the straight section of the outer end of the double-layer corrugated tube of the first test block, and the waveguide probe is moved circumferentially until the first circumferential groove reflection wave heights of all first circumferential grooves 4, the first through-hole distances between all first through-holes 5 and the waveguide probe, and the first through-hole reflection wave heights are collected;

[0231] The waveguide probe is placed at the non-welding area of ​​the straight section of the outer end of the double-layer corrugated tube of the first test block at the first angle to the axial direction, and the waveguide probe is moved circumferentially until the first inclined groove reflection wave heights of all the first inclined grooves 6 are collected;

[0232] The waveguide probe is placed in the non-welding area of ​​the straight section of the outer end of the double-layer corrugated tube of the first test block at the second angle to the axial direction, and the waveguide probe is moved circumferentially until the distance between all the second inclined grooves 7 and the waveguide probe and the second inclined groove reflection wave height are collected;

[0233] All of the first circumferential groove reflection wave heights, the first through-hole distance, the first through-hole reflection wave height corresponding to the first through-hole distance, the first inclined groove reflection wave height, the second inclined groove distance, and the second inclined groove reflection wave height corresponding to the second inclined groove distance are integrated into the scanning results of the multiple first simulated defects.

[0234] For example, the waveguide probe can be used, but not limited to, to scan the end straight section using a waveguide probe, and based on the characteristics of the relevant acoustic wave parameters and waveform diagram fed back by the waveguide probe to the corresponding flaw detector, it can be determined whether the waveguide probe is located in the welded area or the non-welded area, thereby positioning the waveguide probe in the non-welded area of ​​the outer end straight section of the first test block double-layer corrugated tube. It should be noted that the specific implementation method for positioning the waveguide probe in the non-welded area of ​​the outer end straight section of the first test block double-layer corrugated tube can be determined by those skilled in the art based on actual conditions. The above description is only an example and does not constitute a limitation thereto.

[0235] For example, for a first circumferential groove 4, the waveguide probe can be moved circumferentially back and forth for scanning, and the highest reflection wave height of the first circumferential groove 4 obtained by scanning is used as the corresponding first circumferential groove reflection wave height. For a first through-hole 5, the waveguide probe can be moved circumferentially back and forth for scanning, and the highest reflection wave height of the first through-hole 5 obtained by scanning is used as the corresponding first through-hole reflection wave height, and the first through-hole distance of the first through-hole 5 is the first through-hole distance corresponding to the first through-hole reflection wave height. The scanning method for obtaining the first inclined groove reflection wave height, the second inclined groove distance, and the second inclined groove reflection wave height is similar and will not be repeated here. It should be noted that, for the waveguide probe axially set in the non-weld area of ​​the outer end straight section of the double-layer corrugated tube of the first test block, the waveguide probe is moved circumferentially until the first circumferential groove reflection wave height of all first circumferential grooves 4, the first through-hole distances and the first through-hole reflection wave heights of all first through holes 5 and the waveguide probe are collected; the waveguide probe is set in the direction of the first angle to the axial direction in the non-weld area of ​​the outer end straight section of the double-layer corrugated tube of the first test block, and the waveguide probe is moved circumferentially until the first inclined groove reflection wave heights of all first inclined grooves 6 are collected; the waveguide probe is set in the direction of the second angle to the axial direction in the non-weld area of ​​the outer end straight section of the double-layer corrugated tube of the first test block, and the waveguide probe is moved circumferentially until the second inclined groove distances and the second inclined groove reflection wave heights of all second inclined grooves 7 and the waveguide probe are collected. The specific implementation method can be determined by those skilled in the art according to actual conditions. The above description is only an example and does not constitute a limitation to this.

[0236] Through the above steps, the comprehensiveness and accuracy of the scanning and acquisition of the outer layer simulation defect parameters can be improved, thereby improving the accuracy of the first outer layer standard DAC curve and the second outer layer standard DAC curve obtained based on these outer layer simulation defect parameters in the subsequent steps, and further improving the accuracy and comprehensiveness of detecting the outer layer defects of the bellows in the subsequent steps.

[0237] In an optional embodiment, further comprising:

[0238] Before obtaining the inner layer standard DAC curve group based on the scanning results of the plurality of the second simulated defects using the waveguide probe,

[0239] A waveguide probe is axially positioned at the sealing welding area of ​​the straight section of the outer end of the double-layer corrugated tube of the second test block, and the waveguide probe is circumferentially moved until the second circumferential groove reflection wave heights of all second circumferential grooves, the second through-hole distances between all second through-holes and the waveguide probe, and the second through-hole reflection wave heights are collected;

[0240] The waveguide probe is placed at the sealing welding area of ​​the straight section of the outer end of the double-layer corrugated tube of the second test block in a direction forming the third angle with the axial direction, and the waveguide probe is moved circumferentially until the third inclined groove reflection wave height of all third inclined grooves is collected;

[0241] The waveguide probe is placed at the sealing welding area of ​​the straight section of the outer end of the double-layer corrugated tube of the second test block in a direction forming the fourth angle with the axial direction, and the waveguide probe is moved circumferentially until the fourth inclined groove distance and the fourth inclined groove reflection wave height of all the fourth inclined grooves are collected.

[0242] All of the second circumferential groove reflection wave heights, the second through-hole distance, the second through-hole reflection wave height corresponding to the second through-hole distance, the third inclined groove reflection wave height, the fourth inclined groove distance and the fourth inclined groove reflection wave height corresponding to the fourth inclined groove distance are integrated into the scanning results of multiple second simulated defects.

[0243] For example, the end straight section can be scanned by using, but not limited to, a waveguide probe, and based on the characteristics of the relevant acoustic wave parameters and waveform diagram fed back by the waveguide probe to the corresponding flaw detector, it can be determined whether the waveguide probe is located in the sealing area or the non-sealing area, thereby positioning the waveguide probe to the sealing area of ​​the outer end straight section of the second test block double-layer bellows. It should be noted that the specific implementation method of positioning the waveguide probe to the sealing area of ​​the outer end straight section of the second test block double-layer bellows can be determined by those skilled in the art according to actual conditions. The above description is only an example and does not constitute a limitation to this. By setting the waveguide probe in the sealing area of ​​the outer end straight section, the waveguide emitted by it can enter the inner layer of the second test block double-layer bellows from the sealing area, thereby eliminating the need to set the waveguide probe on the inner side of the inner layer for scanning, thereby reducing the difficulty of scanning.

[0244] For example, for a second circumferential groove, the waveguide probe can be moved circumferentially back and forth for scanning, and the highest reflection wave height of the second circumferential groove obtained by scanning is used as the corresponding second circumferential groove reflection wave height. For a second through-hole, the waveguide probe can be moved circumferentially back and forth for scanning, and the highest reflection wave height of the second through-hole obtained by scanning is used as the corresponding second through-hole reflection wave height, and the second through-hole distance of the second through-hole is the second through-hole distance corresponding to the second through-hole reflection wave height. The third inclined groove reflection wave height, the fourth inclined groove distance, and the scanning acquisition method of the fourth inclined groove distance are similar and will not be repeated here. It should be noted that, for the waveguide probe axially set at the sealing welding area of ​​the outer end straight section of the second test block double-layer corrugated tube, the waveguide probe is moved circumferentially until the second circumferential groove reflection wave height of all second circumferential grooves, the second through-hole distances of all second through holes and the waveguide probe, and the second through-hole reflection wave height are collected; the waveguide probe is set at the sealing welding area of ​​the outer end straight section of the second test block double-layer corrugated tube in the direction of the third angle with the axial direction, and the waveguide probe is moved circumferentially until the third inclined groove reflection wave height of all third inclined grooves are collected; the waveguide probe is set at the sealing welding area of ​​the outer end straight section of the second test block double-layer corrugated tube in the direction of the fourth angle with the axial direction, and the waveguide probe is moved circumferentially until the fourth inclined groove distances of all fourth inclined grooves and the fourth inclined groove reflection wave height of the waveguide probe are collected. The specific implementation method can be determined by technical personnel in this field according to actual conditions. The above description is only an example and does not constitute a limitation to this.

[0245] Through the above steps, the comprehensiveness and accuracy of the scanning and acquisition of the relevant inner layer simulation defect parameters can be improved, thereby improving the accuracy of the first inner layer standard DAC curve and the second inner layer standard DAC curve obtained based on these inner layer simulation defect parameters in the subsequent steps, and further improving the accuracy and comprehensiveness of the detection of the inner layer defects of the corrugated pipe in the subsequent steps.

[0246] In an optional embodiment, the detecting of outer layer defects of the target double-layer corrugated pipe based on the first circumferential scanning result of the outer layer 14 of the target double-layer corrugated pipe using a waveguide probe and the outer layer standard DAC curve group includes:

[0247] According to the first circumferential scanning result, a DAC detection curve of the outer circumferential groove and the through hole and a DAC detection curve of the outer inclined groove are obtained;

[0248] Obtaining a first outer layer standard DAC curve and a second outer layer standard DAC curve according to the outer layer standard DAC curve group;

[0249] Detect the corresponding first outer layer distance between the outer layer circumferential groove and the through-hole DAC detection curve, whose height is greater than the corresponding height in the first outer layer standard DAC curve, and determine the first outer layer defect position based on the first outer layer distance and the corresponding first waveguide probe circumferential position; detect the corresponding second outer layer distance between the outer layer inclined groove DAC detection curve, whose height is greater than the corresponding height in the second outer layer standard DAC curve, and determine the second outer layer defect position based on the second outer layer distance and the corresponding second waveguide probe circumferential position, so as to complete the detection of the outer layer defects of the target double-layer corrugated tube.

[0250] Exemplarily, the outer circumferential groove and through-hole DAC detection curve and the outer inclined groove DAC detection curve obtained based on the first circumferential scanning result can be, but is not limited to, obtaining a first circumferential overall DAC detection curve based on the first circumferential scanning result, and then, based on the different characteristics of the circumferential groove, through-hole, and inclined groove and relevant acoustic principles, splitting the first circumferential overall DAC detection curve into the characteristics corresponding to the circumferential groove and through-hole, and the characteristics of the inclined groove, respectively, to obtain the outer circumferential groove and through-hole DAC detection curve and the outer inclined groove DAC detection curve. It should be noted that the specific implementation method for obtaining the outer circumferential groove and through-hole DAC detection curve and the outer inclined groove DAC detection curve based on the first circumferential scanning result can be determined by those skilled in the art according to actual circumstances. The above description is only an example and does not constitute a limitation thereto.

[0251] Exemplarily, since the outer standard DAC curve group includes the first outer standard DAC curve and the second outer standard DAC curve, the first outer standard DAC curve and the second outer standard DAC curve can be directly obtained according to the outer standard DAC curve group.

[0252] Exemplarily, the height corresponds to the amplitude or height of a DAC curve.

[0253] Exemplarily, the outer layer circumferential groove and the corresponding first outer layer distance whose height in the through hole DAC detection curve is greater than the corresponding height in the first outer layer standard DAC curve are detected, as follows:

[0254] In the DAC test curve, the horizontal axis of the coordinate system represents distance and the vertical axis represents height. In the outer layer circumferential groove and through-hole DAC test curve, the distance at a certain point is 310mm, and the corresponding height (amplitude or wave height, etc.) is 7dB. In the first outer layer standard DAC curve, the point with a distance of 310mm corresponds to a height of 5.5dB. Since 7dB is greater than 5.5dB, 310mm can be determined as the corresponding first outer layer distance.

[0255] In the outer layer circumferential groove and through-hole DAC test curve, the distance between another point is 280mm, and the corresponding height (amplitude or wave height, etc.) is 10dB. In the first outer layer standard DAC curve, the point at a distance of 280mm has a corresponding height of 9dB. Since 10dB is greater than 9dB, 280mm can be determined as the corresponding first outer layer distance.

[0256] It should be noted that the specific implementation method for detecting the outer layer circumferential groove and the corresponding first outer layer distance whose height in the through-hole DAC detection curve is greater than the corresponding height in the first outer layer standard DAC curve can be determined by those skilled in the art according to actual conditions. The above description is only an example and does not constitute a limitation to this.

[0257] For example, the process of detecting the second outer layer distance corresponding to a height in the outer layer inclined groove DAC test curve that is greater than the corresponding height in the second outer layer standard DAC curve is based on the same principle as the process of detecting the first outer layer distance corresponding to a height in the outer layer circumferential groove and through-hole DAC test curve that is greater than the corresponding height in the first outer layer standard DAC curve, and will not be further described here. The specific implementation of the above process can be determined by those skilled in the art based on actual circumstances and is not limited in this embodiment of the present invention.

[0258] Through the above steps, defects such as circumferential cracks, inclined cracks at different angles, and pitting perforations in the outer layer 14 of the target double-layer corrugated pipe can be determined more accurately, conveniently, and quickly without requiring more steps, further reducing the difficulty of detecting outer layer defects.

[0259] In an optional embodiment, the detecting of inner layer defects of the target double-layer corrugated pipe based on the second circumferential scanning result of the inner layer 13 of the target double-layer corrugated pipe using a waveguide probe and the inner layer standard DAC curve group includes:

[0260] According to the second circumferential scanning result, a DAC detection curve of the inner layer circumferential groove and through hole and a DAC detection curve of the inner layer inclined groove are obtained;

[0261] Obtaining a first inner layer standard DAC curve and a second inner layer standard DAC curve according to the inner layer standard DAC curve group;

[0262] Detect the corresponding first inner layer distance between the inner layer circumferential groove and the through hole DAC detection curve, whose height is greater than the corresponding height in the first inner layer standard DAC curve, and determine the first inner layer defect position based on the first inner layer distance and the corresponding third waveguide probe circumferential position, detect the corresponding second inner layer distance between the inner layer inclined groove DAC detection curve, whose height is greater than the corresponding height in the second inner layer standard DAC curve, and determine the second inner layer defect position based on the second inner layer distance and the corresponding fourth waveguide probe circumferential position, so as to complete the detection of the inner layer defects of the target double-layer corrugated tube.

[0263] Exemplarily, the DAC detection curves for the inner circumferential grooves and through-holes and the DAC detection curves for the inner inclined grooves obtained based on the second circumferential scanning results may be, but are not limited to, obtaining a second circumferential overall DAC detection curve based on the second circumferential scanning results, and then, based on the different characteristics of the circumferential grooves, through-holes, and inclined grooves and relevant acoustic principles, separating the second circumferential overall DAC detection curve into the characteristics corresponding to the circumferential grooves and through-holes, and the characteristics of the inclined grooves, respectively, to obtain the DAC detection curves for the inner circumferential grooves and through-holes and the DAC detection curves for the inner inclined grooves. It should be noted that the specific implementation method for obtaining the DAC detection curves for the inner circumferential grooves and through-holes and the DAC detection curves for the inner inclined grooves based on the second circumferential scanning results can be determined by those skilled in the art based on actual circumstances, and the above description is merely an example and does not constitute a limitation thereto.

[0264] Exemplarily, since the inner standard DAC curve group includes the first inner standard DAC curve and the second inner standard DAC curve, the first inner standard DAC curve and the second inner standard DAC curve can be directly obtained according to the inner standard DAC curve group.

[0265] Exemplarily, the height corresponds to the amplitude or height of a DAC curve.

[0266] Exemplarily, the first inner layer distance corresponding to the inner layer circumferential groove and the through hole DAC detection curve whose height is greater than the corresponding height in the first inner layer standard DAC curve is detected, as follows:

[0267] In the DAC test curve, the horizontal axis of the coordinate system represents distance and the vertical axis represents height. In the inner layer circumferential groove and through-hole DAC test curve, the distance at a certain point is 305mm, and the corresponding height (amplitude or wave height, etc.) is 6.6dB. In the first inner layer standard DAC curve, the point with a distance of 305mm has a corresponding height of 6.5dB. Since 6.6dB is greater than 6.5dB, 305mm can be determined as the corresponding first inner layer distance.

[0268] In the inner layer circumferential groove and through-hole DAC test curve, the distance to another point is 240mm, and the corresponding height (amplitude or wave height, etc.) is 12dB. In the first inner layer standard DAC curve, the point at a distance of 240mm has a corresponding height of 11.5dB. Since 12dB is greater than 11.5dB, 240mm can be determined as the corresponding first inner layer distance.

[0269] It should be noted that the specific implementation method for detecting the corresponding first inner layer distance between the inner layer circumferential groove and the through-hole DAC detection curve whose height is greater than the corresponding height in the first inner layer standard DAC curve can be determined by those skilled in the art based on actual conditions. The above description is only an example and does not constitute a limitation to this.

[0270] For example, the process of detecting the second inner layer distance corresponding to a height greater than the corresponding height in the second inner layer standard DAC curve in the inner layer inclined groove DAC test curve is based on the same principle as the process of detecting the first inner layer distance corresponding to a height greater than the corresponding height in the inner layer circumferential groove and through-hole DAC test curve in the inner layer circumferential groove and through-hole DAC test curve, and will not be further described here. The specific implementation of the above process can be determined by those skilled in the art based on actual circumstances and is not limited in this embodiment of the present invention.

[0271] Through the above steps, defects such as circumferential cracks, inclined cracks at different angles, and pitting perforations in the inner layer 13 of the target double-layer corrugated pipe can be determined more accurately, conveniently, and quickly without requiring many steps, further reducing the difficulty of detecting inner layer defects.

[0272] In an optional embodiment, if Figure 5 As shown, the outer circumferential groove and through-hole DAC detection curve is obtained by axially setting the waveguide probe in the non-sealing area 10 of the straight section of the outer end of the target double-layer corrugated tube, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle.

[0273] For example, for defects such as outer circumferential cracks and perforations, the flaw detector can be configured with a corresponding first scanning mode channel by adjusting relevant parameters of the flaw detector based on relevant physical properties and parameter characteristics. When scanning and determining the DAC detection curves for the outer circumferential grooves and through-holes, the flaw detector's configuration channel can be set to the first scanning mode channel to further improve the accuracy of the scanned DAC detection curves for the outer circumferential grooves and through-holes. It should be noted that the specific scanning and determination method for the outer circumferential grooves and through-holes DAC detection curves can be determined by those skilled in the art based on actual circumstances, and the above description is merely an example and does not constitute a limitation.

[0274] By making the outer layer circumferential groove and through hole DAC detection curve axially set the waveguide probe in the non-sealing area 10 of the straight section of the outer layer end of the target double-layer corrugated pipe, and moving the waveguide probe along the circumference of the target double-layer corrugated pipe for one circle for detection, the steps and difficulty of scanning to determine the outer layer circumferential groove and through hole DAC detection curve can be further reduced, thereby further improving the efficiency of determining the outer layer defects of the target corrugated pipe.

[0275] In an optional embodiment, the outer layer inclined groove DAC detection curve is obtained by setting the waveguide probe in the non-welding area 10 of the straight section of the outer layer end of the target double-layer corrugated pipe in a direction with the first angle to the axial direction, and moving the waveguide probe along the circumference of the target double-layer corrugated pipe for one circle.

[0276] For example, for the defects of inclined cracks with different inclination angles in the outer layer, based on the relevant physical properties and parameter characteristics, the relevant parameters of the flaw detector can be adjusted to set the corresponding second scanning mode channel, and when scanning to determine the outer layer inclined groove DAC detection curve, the configuration channel of the flaw detector is set to the second scanning mode channel to further improve the accuracy of the outer layer inclined groove DAC detection curve obtained by scanning. It should be noted that the specific scanning and determination method for the outer layer inclined groove DAC detection curve can be determined by those skilled in the art according to actual conditions. The above description is only an example and does not constitute a limitation. For example, the waveguide probe is set in the direction of the first angle with the axial direction to the non-sealing area 10 of the straight section of the outer layer end of the target double-layer corrugated pipe, and the waveguide probe is moved along the circumference of the target double-layer corrugated pipe for one circle, so that at least the outer layer inclined groove DAC detection curve can reflect the outer layer inclined crack defects at the first angle and the second angle with the circumference.

[0277] By making the outer layer inclined groove DAC detection curve, the waveguide probe is set in the direction of the first angle with the axial direction at the non-sealing area 10 of the straight section of the outer layer end of the target double-layer corrugated pipe, and the waveguide probe is moved along the circumference of the target double-layer corrugated pipe for one circle for detection. This can further reduce the steps and difficulty of scanning to determine the outer layer inclined groove DAC detection curve, thereby further improving the efficiency of determining the outer layer defects of the target corrugated pipe.

[0278] In an optional embodiment, the inner circumferential groove and through-hole DAC detection curve is obtained by axially setting the waveguide probe in the sealing area 11 of the straight section of the outer end of the target double-layer corrugated tube, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle.

[0279] For example, for defects such as inner layer circumferential cracks and perforations, the flaw detector can be configured to have a corresponding third scanning mode channel by adjusting relevant parameters of the flaw detector based on relevant physical properties and parameter characteristics. When scanning and determining the DAC detection curves for the inner layer circumferential grooves and through-holes, the flaw detector's configuration channel can be set to the third scanning mode channel to further improve the accuracy of the scanned DAC detection curves for the inner layer circumferential grooves and through-holes. It should be noted that the specific scanning and determination method for the DAC detection curves for the inner layer circumferential grooves and through-holes can be determined by those skilled in the art based on actual circumstances, and the above description is merely an example and does not constitute a limitation.

[0280] like Figure 5 As shown, the waveguide probe is axially arranged at the sealing area 11 of the straight section of the outer end of the target double-layer corrugated pipe, so that the detection waveguide can enter the inner layer 13 of the target double-layer corrugated pipe along the sealing area without being blocked by the gap 15, thereby being able to scan the inner layer defects of the target double-layer corrugated pipe. Moreover, there is no need to set the waveguide probe inside the inner layer of the target double-layer corrugated pipe, so that for the target double-layer corrugated pipe that has been installed on the relevant equipment, it is not necessary to remove it separately when detecting its inner layer defects, thereby reducing the relevant steps and processes, thereby reducing the difficulty and time of detecting its inner layer defects, and improving the efficiency of detecting defects in the inner layer 13 of the target double-layer corrugated pipe.

[0281] By making the inner layer circumferential groove and through hole DAC detection curve be obtained by axially setting the waveguide probe at the sealing area 11 of the straight section of the outer layer end of the target double-layer corrugated tube, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle for detection, the steps and difficulty of scanning to determine the inner layer circumferential groove and through hole DAC detection curve can be further reduced, thereby further improving the efficiency of determining the inner layer defects of the target corrugated tube.

[0282] In an optional embodiment, the inner layer inclined groove DAC detection curve is obtained by setting the waveguide probe in the direction of the third angle with the axial direction at the sealing area 11 of the straight section of the outer layer end of the target double-layer corrugated tube, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle.

[0283] For example, for the defects of inclined cracks with different inclination angles in the inner layer, based on the relevant physical properties and parameter characteristics, the relevant parameters of the flaw detector can be adjusted to set the corresponding fourth scanning mode channel, and when scanning to determine the inner layer inclined groove DAC detection curve, the configuration channel of the flaw detector is set to the fourth scanning mode channel to further improve the accuracy of the scanned inner layer inclined groove DAC detection curve. It should be noted that the specific scanning and determination method for the inner layer inclined groove DAC detection curve can be determined by those skilled in the art according to actual conditions. The above description is only an example and does not constitute a limitation. For example, the waveguide probe is set in the direction of the third angle with the axial direction at the sealing area 11 of the straight section of the outer layer end of the target double-layer corrugated pipe, and the waveguide probe is moved along the circumference of the target double-layer corrugated pipe for one circle, so that at least the inner layer inclined groove DAC detection curve can reflect the inner layer inclined crack defects at the third and fourth angles with the circumference.

[0284] By making the inner layer inclined groove DAC detection curve, the waveguide probe is set in the direction of the third angle with the axial direction at the sealing area 11 of the straight section of the outer layer end of the target double-layer corrugated pipe, and the waveguide probe is moved along the circumference of the target double-layer corrugated pipe for one circle for detection. This can further reduce the steps and difficulty of scanning to determine the inner layer inclined groove DAC detection curve, thereby further improving the efficiency of determining the inner layer defects of the target corrugated pipe.

[0285] In an optional embodiment, the inner circumferential groove and through-hole DAC detection curve is obtained by axially setting the waveguide probe in the non-sealing area 12 of the straight section of the inner end of the target double-layer corrugated tube, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle.

[0286] On the basis that the target double-layer corrugated tube has been removed from the corresponding equipment, the waveguide probe can also be axially set in the non-sealed area 12 of the straight section of the inner end of the target double-layer corrugated tube to scan and determine the inner layer circumferential groove and the through-hole DAC detection curve. This can reduce the loss of the waveguide, thereby further improving the accuracy of scanning and determining the inner layer circumferential groove and the through-hole DAC detection curve, and further improving the accuracy of detecting the circumferential crack defects and perforation defects in the inner layer 13 of the target double-layer corrugated tube.

[0287] In an optional embodiment, the inner layer inclined groove DAC detection curve is obtained by setting the waveguide probe in the direction of the third angle with the axial direction at the non-welding area 12 of the inner layer end straight section of the target double-layer corrugated tube, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle.

[0288] On the basis that the target double-layer corrugated tube has been removed from the corresponding equipment, the waveguide probe can also be set in the direction of the third angle with the axial direction at the non-sealed area 12 of the straight section of the inner layer end of the target double-layer corrugated tube to scan and determine the inner layer inclined groove DAC detection curve. This can reduce the loss of the waveguide, thereby further improving the accuracy of scanning and determining the inner layer inclined groove DAC detection curve, and further improving the accuracy of detecting the inclined crack defect in the inner layer 13 of the target double-layer corrugated tube.

[0289] Among them, the flaw detector can directly generate the relevant DAC detection curve based on the feedback guided wave signal collected by the guided wave probe during a round scan.

[0290] In an optional embodiment, integrating all of the first circumferential groove reflection wave heights, the first through-hole distance, the first through-hole reflection wave height corresponding to the first through-hole distance, the first inclined groove reflection wave height, the second inclined groove distance, and the second inclined groove reflection wave height corresponding to the second inclined groove distance into a scanning result of the plurality of first simulated defects includes:

[0291] Obtaining a corresponding first circumferential groove echo gain according to the first circumferential groove reflection wave height;

[0292] Obtaining a corresponding first through-hole echo gain according to the first through-hole reflection wave height;

[0293] Performing a linear fit between the first through-hole distance and the corresponding first through-hole reflection wave height to obtain a first through-hole DAC equivalent line;

[0294] Obtaining a corresponding first inclined groove echo gain according to the first inclined groove reflection wave height;

[0295] Obtaining a corresponding second inclined groove echo gain according to the second inclined groove reflection wave height;

[0296] Performing a linear fit on the second inclined groove distance and the corresponding second inclined groove reflection wave height to obtain a second inclined groove DAC equivalent line;

[0297] All of the first circumferential groove echo gains, first through-hole echo gains, first through-hole DAC equivalent lines, first inclined groove echo gains, second inclined groove echo gains, and second inclined groove DAC equivalent lines are aggregated to obtain scanning results of the plurality of the first simulated defects.

[0298] For example, obtaining the corresponding gain according to the wave height is a conventional technical means in this field and will not be described in detail here.

[0299] Exemplarily, the linear fitting of the first through-hole distance and the corresponding first through-hole reflection wave height to obtain the first through-hole DAC equivalent line may be, but is not limited to, obtaining multiple first through-hole DAC equivalent points based on multiple first through-hole distances and the corresponding first through-hole reflection wave heights, and performing linear fitting on all first through-hole DAC equivalent points to obtain the first through-hole DAC equivalent line.

[0300] Exemplarily, the second inclined groove distance and the corresponding second inclined groove reflection wave height are linearly fitted to obtain the second inclined groove DAC equivalent line. It can be, but is not limited to, obtaining multiple second inclined groove DAC equivalent points based on multiple second inclined groove distances and corresponding second inclined groove reflection wave heights, and linearly fitting all second inclined groove DAC equivalent points to obtain the second inclined groove DAC equivalent line.

[0301] Through the above steps, the scanning results of multiple first simulated defects can have more mature data, so that when the scanning results of multiple first simulated defects are used to determine the outer layer standard DAC curve group, no more preprocessing steps are required, thereby reducing the time to obtain the outer layer standard DAC curve group, and indirectly improving the efficiency of detecting the outer layer of the target double-layer corrugated pipe.

[0302] In an optional embodiment, integrating all of the second circumferential groove reflection wave heights, the second through-hole distance, the second through-hole reflection wave height corresponding to the second through-hole distance, the third inclined groove reflection wave height, the fourth inclined groove distance, and the fourth inclined groove reflection wave height corresponding to the fourth inclined groove distance into a scanning result of the plurality of second simulated defects includes:

[0303] Obtaining a corresponding second circumferential groove echo gain according to the second circumferential groove reflection wave height;

[0304] Obtaining a corresponding second through-hole echo gain according to the second through-hole reflection wave height;

[0305] Performing a linear fit on the second through-hole distance and the corresponding second through-hole reflection wave height to obtain a second through-hole DAC equivalent line;

[0306] Obtaining a corresponding third inclined groove echo gain according to the third inclined groove reflection wave height;

[0307] Obtaining a corresponding fourth inclined groove echo gain according to the fourth inclined groove reflection wave height;

[0308] Performing linear fitting on the fourth inclined groove distance and the corresponding fourth inclined groove reflection wave height to obtain a fourth inclined groove DAC equivalent line;

[0309] All the second circumferential groove echo gains, second through-hole echo gains, second through-hole DAC equivalent lines, third inclined groove echo gains, fourth inclined groove echo gains and fourth inclined groove DAC equivalent lines are aggregated to obtain scanning results of multiple second simulated defects.

[0310] For example, obtaining the corresponding gain according to the wave height is a conventional technical means in this field and will not be described in detail here.

[0311] Exemplarily, the second through-hole distance and the corresponding second through-hole reflection wave height are linearly fitted to obtain the second through-hole DAC equivalent line. It can be, but is not limited to, obtaining multiple second through-hole DAC equivalent points based on multiple second through-hole distances and corresponding second through-hole reflection wave heights, and linearly fitting all second through-hole DAC equivalent points to obtain the second through-hole DAC equivalent line.

[0312] Exemplarily, the fourth inclined groove distance and the corresponding fourth inclined groove reflection wave height are linearly fitted to obtain the fourth inclined groove DAC equivalent line. It can be, but is not limited to, obtaining multiple fourth inclined groove DAC equivalent points based on multiple fourth inclined groove distances and corresponding fourth inclined groove reflection wave heights, and linearly fitting all fourth inclined groove DAC equivalent points to obtain the fourth inclined groove DAC equivalent line.

[0313] Through the above steps, the scanning results of multiple second-layer simulated defects can have more mature data, so that when the scanning results of multiple second-layer simulated defects are used to determine the inner layer standard DAC curve group, no more preprocessing steps are required, thereby reducing the time for obtaining the inner layer standard DAC curve group, and indirectly improving the efficiency of detecting the inner layer of the target double-layer corrugated pipe.

[0314] Based on the same principle, an embodiment of the present invention discloses a test block, including an outer layer test block and an inner layer test block;

[0315] The outer layer inspection test block includes a first test block double-layer bellows and a plurality of first simulated defects provided on the first test block double-layer bellows;

[0316] The first simulated defects include a plurality of first circumferential grooves in a preset first circumferential groove area, a plurality of first through holes in a preset first through hole area, and a plurality of first special grooves in a preset first special groove area, which are respectively arranged on the outer layer of the double-layer bellows of the first test block;

[0317] The inner layer inspection test block includes a second test block double-layer bellows and a plurality of second simulated defects provided on the second test block double-layer bellows;

[0318] The second simulated defects include a plurality of second circumferential grooves in a preset second circumferential groove area, a plurality of second through holes in a preset second through hole area, and a plurality of second special grooves in a preset second special groove area, respectively arranged on the inner layer of the double-layer bellows of the second test block.

[0319] The test block provided by the present invention makes the outer layer inspection test block include a first test block double-layer bellows and a plurality of first simulated defects arranged on the first test block double-layer bellows; wherein the first simulated defects include a plurality of first circumferential grooves in a preset first circumferential groove area, a plurality of first through holes in a preset first through hole area and a plurality of first special grooves in a preset first special groove area respectively arranged on the outer layer of the first test block double-layer bellows, which can accurately simulate the groove-type defects of the outer layer of an actual double-layer bellows, namely cracks in different directions and through hole-type defects, thereby improving the accuracy of the outer layer standard DAC curve group used for detecting outer layer defects determined based on the outer layer inspection test block in subsequent steps, thereby improving the accuracy of subsequent outer layer defect detection. By making the inner layer inspection test block include a second test block double-layer bellows and a plurality of second simulated defects arranged on the second test block double-layer bellows; wherein the second simulated defects include a plurality of second circumferential grooves in a preset second circumferential groove area, a plurality of second through holes in a preset second through hole area and a plurality of second special grooves in a preset second special groove area respectively arranged on the inner layer of the second test block double-layer bellows, it is possible to accurately simulate the groove-type defects of the inner layer in the actual double-layer bellows, i.e., cracks in different directions and through-hole-type defects, thereby improving the accuracy of the inner layer standard DAC curve group used for detecting inner layer defects determined based on the inner layer inspection test block in subsequent steps, thereby improving the accuracy of subsequent outer layer defect detection.

[0320] Based on the same principle, an embodiment of the present invention discloses a double-layer corrugated pipe defect detection device 600 based on ultrasonic guided waves. The device is implemented using test blocks, wherein the test blocks include an outer layer detection test block and an inner layer detection test block;

[0321] The outer layer inspection test block includes a first test block double-layer bellows and a plurality of first simulated defects provided on the first test block double-layer bellows;

[0322] The first simulated defects include a plurality of first circumferential grooves in a preset first circumferential groove area, a plurality of first through holes in a preset first through hole area, and a plurality of first special grooves in a preset first special groove area, which are respectively arranged on the outer layer of the double-layer bellows of the first test block;

[0323] The inner layer inspection test block includes a second test block double-layer bellows and a plurality of second simulated defects provided on the second test block double-layer bellows;

[0324] The second simulated defects include a plurality of second circumferential grooves in a preset second circumferential groove area, a plurality of second through holes in a preset second through hole area, and a plurality of second special grooves in a preset second special groove area, respectively arranged on the inner layer of the double-layer bellows of the second test block.

[0325] like Figure 6 As shown, the double-layer corrugated pipe defect detection device 600 based on ultrasonic guided waves includes:

[0326] The standard DAC curve generation module 601 is configured to obtain an outer layer standard DAC curve group based on the scanning results of the plurality of first simulated defects using a waveguide probe; and obtain an inner layer standard DAC curve group based on the scanning results of the plurality of second simulated defects using a waveguide probe;

[0327] The bellows defect detection module 602 is used to detect the outer layer defects of the target double-layer corrugated tube based on the first circumferential scanning result of the outer layer of the target double-layer corrugated tube using a waveguide probe and the outer layer standard DAC curve group; and to detect the inner layer defects of the target double-layer corrugated tube based on the second circumferential scanning result of the inner layer of the target double-layer corrugated tube using a waveguide probe and the inner layer standard DAC curve group.

[0328] In an optional embodiment, the first circumferential grooves are respectively provided on the inner surface of a plurality of first preset wave crests and the outer surface of a plurality of first preset wave troughs of the outer layer of the double-layer corrugated tube of the first test block.

[0329] In an optional embodiment, the first through holes are respectively provided at a plurality of the first preset wave crests and a plurality of the first preset wave troughs of the outer layer of the double-layer corrugated tube of the first test block.

[0330] In an optional embodiment, the first special grooves include a plurality of first inclined grooves forming a first angle with the circumferential direction and a plurality of second inclined grooves forming a second angle with the circumferential direction; wherein the first angle and the second angle are acute angles.

[0331] In an optional embodiment, the first inclined grooves are respectively arranged on the inner surface of the multiple first preset peaks and the outer surface of the multiple first preset troughs of the outer layer of the double-layer corrugated tube of the first test block; the second inclined grooves are respectively arranged on the inner surface of the multiple first preset peaks and the outer surface of the multiple first preset troughs of the outer layer of the double-layer corrugated tube of the first test block.

[0332] In an optional embodiment, the circumferential spacing distance between multiple first simulated defects arranged at the same wave crest of the first test block double-layer corrugated tube is greater than the preset first defect spacing distance; the circumferential spacing distance between multiple first simulated defects arranged at the same wave trough of the first test block double-layer corrugated tube is greater than the first defect spacing distance.

[0333] In an optional embodiment, the second circumferential grooves are respectively arranged on the inner surface of multiple second preset peaks and the outer surface of multiple second preset troughs of the inner layer of the double-layer corrugated tube of the second test block.

[0334] In an optional embodiment, the second through holes are respectively provided at a plurality of the second preset wave crests and a plurality of the second preset wave troughs of the inner layer of the double-layer corrugated tube of the second test block.

[0335] In an optional embodiment, the second special grooves include a plurality of third inclined grooves forming a third angle with the circumferential direction and a plurality of fourth inclined grooves forming a fourth angle with the circumferential direction; wherein the third angle and the fourth angle are acute angles.

[0336] In an optional embodiment, the third inclined groove is respectively arranged on the inner surface of the multiple second preset peaks and the outer surface of the multiple second preset troughs of the inner layer of the double-layer corrugated tube of the second test block; the fourth inclined groove is respectively arranged on the inner surface of the multiple second preset peaks and the outer surface of the multiple second preset troughs of the inner layer of the double-layer corrugated tube of the second test block.

[0337] In an optional embodiment, the circumferential spacing distance between multiple second simulated defects set at the same wave crest of the second test block double-layer corrugated tube is greater than the preset second defect spacing distance; the circumferential spacing distance between multiple second simulated defects set at the same wave trough of the second test block double-layer corrugated tube is greater than the second defect spacing distance.

[0338] In an optional embodiment, the standard DAC curve generating module 601 is configured to:

[0339] According to the scanning results of the plurality of first simulated defects, a first circumferential groove echo gain corresponding to each first circumferential groove, a first through-hole DAC equivalent line, a first through-hole echo gain corresponding to each first through-hole, a first oblique groove echo gain corresponding to each first oblique groove, a second oblique groove DAC equivalent line, and a second oblique groove echo gain corresponding to each second oblique groove are obtained;

[0340] Obtaining a first outer layer standard DAC curve according to the first circumferential groove echo gain, the first through-hole DAC equivalent line, and the first through-hole echo gain;

[0341] Obtaining a second outer layer standard DAC curve according to the first inclined groove echo gain, the second inclined groove DAC equivalent line and the second inclined groove echo gain;

[0342] The first outer layer standard DAC curve and the second outer layer standard DAC curve are clustered to obtain an outer layer standard DAC curve group.

[0343] In an optional embodiment, the standard DAC curve generating module 601 is configured to:

[0344] subtracting the corresponding first through-hole echo gain from each first circumferential groove echo gain to obtain a plurality of first gain differences, and taking an average of the plurality of first gain differences as a first average gain difference;

[0345] Performing a gain operation on the first through-hole DAC equivalent line based on the first average gain difference to obtain a first quantitative line;

[0346] A gain operation is performed on the first quantitative line based on a preset first optimized gain equivalent to obtain the first outer standard DAC curve.

[0347] In an optional embodiment, the standard DAC curve generating module 601 is configured to:

[0348] subtracting the corresponding second inclined groove echo gain from each first inclined groove echo gain to obtain a plurality of second gain differences, and taking an average of the plurality of second gain differences as a second average gain difference;

[0349] Performing a gain operation on the second inclined groove DAC equivalent line based on the second average gain difference to obtain a second quantitative line;

[0350] A gain operation is performed on the second quantitative line based on a preset second optimized gain equivalent to obtain the second outer layer standard DAC curve.

[0351] In an optional embodiment, the standard DAC curve generating module 601 is configured to:

[0352] According to the scanning results of the plurality of second simulated defects, a second circumferential groove echo gain corresponding to each second circumferential groove, a second through-hole DAC equivalent line, a second through-hole echo gain corresponding to each second through-hole, a third oblique groove echo gain corresponding to each third oblique groove, a fourth oblique groove DAC equivalent line, and a fourth oblique groove echo gain corresponding to each fourth oblique groove are obtained;

[0353] Obtaining a first inner layer standard DAC curve according to the second circumferential groove echo gain, the second through-hole DAC equivalent line, and the second through-hole echo gain;

[0354] Obtaining a second inner layer standard DAC curve according to the third inclined groove echo gain, the fourth inclined groove DAC equivalent line and the fourth inclined groove echo gain;

[0355] The first inner layer standard DAC curve and the second inner layer standard DAC curve are clustered to obtain an inner layer standard DAC curve group.

[0356] In an optional embodiment, the standard DAC curve generating module 601 is configured to:

[0357] Subtracting the corresponding second through-hole echo gain from each second circumferential groove echo gain to obtain a plurality of third gain differences, and taking an average of the plurality of third gain differences as a third average gain difference;

[0358] Performing a gain operation on the second through-hole DAC equivalent line based on the third average gain difference to obtain a third quantitative line;

[0359] A gain operation is performed on the third quantitative line based on a preset third optimized gain equivalent to obtain the first inner layer standard DAC curve.

[0360] In an optional embodiment, the standard DAC curve generating module 601 is configured to:

[0361] subtracting the corresponding fourth inclined groove echo gain from each third inclined groove echo gain to obtain a plurality of fourth gain differences, and taking an average of the plurality of fourth gain differences as a fourth average gain difference;

[0362] Performing a gain operation on the fourth inclined groove DAC equivalent line based on the fourth average gain difference to obtain a fourth quantitative line;

[0363] A gain operation is performed on the fourth quantitative line based on a preset fourth optimized gain equivalent to obtain the second inner layer standard DAC curve.

[0364] In an optional embodiment, the system further includes a first simulated defect scanning result determination module, configured to:

[0365] Before obtaining the outer layer standard DAC curve group based on the scanning results of the plurality of the first simulated defects using the waveguide probe,

[0366] A waveguide probe is axially positioned at a non-welding area of ​​a straight section of an outer end portion of the double-layer bellows of the first test block, and the waveguide probe is circumferentially moved until the first circumferential groove reflection wave heights of all first circumferential grooves, the first through-hole distances between all first through-holes and the waveguide probe, and the first through-hole reflection wave heights are collected;

[0367] The waveguide probe is placed at a non-welding area of ​​the straight section of the outer end of the double-layer corrugated tube of the first test block at the first angle to the axial direction, and the waveguide probe is moved circumferentially until the reflection wave heights of all the first inclined grooves are collected;

[0368] The waveguide probe is placed at the non-welding area of ​​the straight section of the outer end of the double-layer corrugated tube of the first test block at the second angle to the axial direction, and the waveguide probe is moved circumferentially until the distance between all the second inclined grooves and the waveguide probe and the second inclined groove reflection wave height are collected;

[0369] All of the first circumferential groove reflection wave heights, the first through-hole distance, the first through-hole reflection wave height corresponding to the first through-hole distance, the first inclined groove reflection wave height, the second inclined groove distance, and the second inclined groove reflection wave height corresponding to the second inclined groove distance are integrated into the scanning results of the multiple first simulated defects.

[0370] In an optional embodiment, the system further includes a second simulated defect scanning result determination module, configured to:

[0371] Before obtaining the inner layer standard DAC curve group based on the scanning results of the plurality of the second simulated defects using the waveguide probe,

[0372] A waveguide probe is axially positioned at the sealing welding area of ​​the straight section of the outer end of the double-layer corrugated tube of the second test block, and the waveguide probe is circumferentially moved until the second circumferential groove reflection wave heights of all second circumferential grooves, the second through-hole distances between all second through-holes and the waveguide probe, and the second through-hole reflection wave heights are collected;

[0373] The waveguide probe is placed at the sealing welding area of ​​the straight section of the outer end of the double-layer corrugated tube of the second test block in a direction forming the third angle with the axial direction, and the waveguide probe is moved circumferentially until the third inclined groove reflection wave height of all third inclined grooves is collected;

[0374] The waveguide probe is placed at the sealing welding area of ​​the straight section of the outer end of the double-layer corrugated tube of the second test block in a direction forming the fourth angle with the axial direction, and the waveguide probe is moved circumferentially until the fourth inclined groove distance and the fourth inclined groove reflection wave height of all the fourth inclined grooves are collected.

[0375] All of the second circumferential groove reflection wave heights, the second through-hole distance, the second through-hole reflection wave height corresponding to the second through-hole distance, the third inclined groove reflection wave height, the fourth inclined groove distance and the fourth inclined groove reflection wave height corresponding to the fourth inclined groove distance are integrated into the scanning results of multiple second simulated defects.

[0376] In an optional embodiment, the bellows defect detection module 602 is configured to:

[0377] According to the first circumferential scanning result, a DAC detection curve of the outer circumferential groove and the through hole and a DAC detection curve of the outer inclined groove are obtained;

[0378] Obtaining a first outer layer standard DAC curve and a second outer layer standard DAC curve according to the outer layer standard DAC curve group;

[0379] Detect the corresponding first outer layer distance between the outer layer circumferential groove and the through-hole DAC detection curve, whose height is greater than the corresponding height in the first outer layer standard DAC curve, and determine the first outer layer defect position based on the first outer layer distance and the corresponding first waveguide probe circumferential position; detect the corresponding second outer layer distance between the outer layer inclined groove DAC detection curve, whose height is greater than the corresponding height in the second outer layer standard DAC curve, and determine the second outer layer defect position based on the second outer layer distance and the corresponding second waveguide probe circumferential position, so as to complete the detection of the outer layer defects of the target double-layer corrugated tube.

[0380] In an optional embodiment, the bellows defect detection module 602 is configured to:

[0381] According to the second circumferential scanning result, a DAC detection curve of the inner layer circumferential groove and through hole and a DAC detection curve of the inner layer inclined groove are obtained;

[0382] Obtaining a first inner layer standard DAC curve and a second inner layer standard DAC curve according to the inner layer standard DAC curve group;

[0383] Detect the corresponding first inner layer distance between the inner layer circumferential groove and the through hole DAC detection curve, whose height is greater than the corresponding height in the first inner layer standard DAC curve, and determine the first inner layer defect position based on the first inner layer distance and the corresponding third waveguide probe circumferential position, detect the corresponding second inner layer distance between the inner layer inclined groove DAC detection curve, whose height is greater than the corresponding height in the second inner layer standard DAC curve, and determine the second inner layer defect position based on the second inner layer distance and the corresponding fourth waveguide probe circumferential position, so as to complete the detection of the inner layer defects of the target double-layer corrugated tube.

[0384] In an optional embodiment, the outer circumferential groove and through-hole DAC detection curve is obtained by axially setting the waveguide probe in the non-welding area of ​​the straight section of the outer end of the target double-layer corrugated tube, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle.

[0385] In an optional embodiment, the outer layer inclined groove DAC detection curve is obtained by setting the waveguide probe in the non-welding area of ​​the straight section of the outer layer end of the target double-layer corrugated tube in the direction of the first angle with the axial direction, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle.

[0386] In an optional embodiment, the inner circumferential groove and through-hole DAC detection curve is obtained by axially setting the waveguide probe in the sealing area of ​​the straight section of the outer end of the target double-layer corrugated tube, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle.

[0387] In an optional embodiment, the inner layer inclined groove DAC detection curve is obtained by setting the waveguide probe in the direction of the third angle with the axial direction in the sealing area of ​​the straight section of the outer end of the target double-layer corrugated tube, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle.

[0388] In an optional embodiment, the inner circumferential groove and through-hole DAC detection curve is obtained by axially setting the waveguide probe in the non-sealing area of ​​the straight section of the inner end of the target double-layer corrugated tube, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle.

[0389] In an optional embodiment, the inner layer inclined groove DAC detection curve is obtained by setting the waveguide probe in the non-welding area of ​​the straight section of the inner layer end of the target double-layer corrugated tube in the direction of the third angle with the axial direction, and moving the waveguide probe along the circumference of the target double-layer corrugated tube for one circle.

[0390] In an optional embodiment, the first simulated defect scanning result determination module is configured to:

[0391] Obtaining a corresponding first circumferential groove echo gain according to the first circumferential groove reflection wave height;

[0392] Obtaining a corresponding first through-hole echo gain according to the first through-hole reflection wave height;

[0393] Performing a linear fit between the first through-hole distance and the corresponding first through-hole reflection wave height to obtain a first through-hole DAC equivalent line;

[0394] Obtaining a corresponding first inclined groove echo gain according to the first inclined groove reflection wave height;

[0395] Obtaining a corresponding second inclined groove echo gain according to the second inclined groove reflection wave height;

[0396] Performing a linear fit on the second inclined groove distance and the corresponding second inclined groove reflection wave height to obtain a second inclined groove DAC equivalent line;

[0397] All of the first circumferential groove echo gains, first through-hole echo gains, first through-hole DAC equivalent lines, first inclined groove echo gains, second inclined groove echo gains, and second inclined groove DAC equivalent lines are aggregated to obtain scanning results of the plurality of the first simulated defects.

[0398] In an optional embodiment, the second simulated defect scanning result determination module is configured to:

[0399] Obtaining a corresponding second circumferential groove echo gain according to the second circumferential groove reflection wave height;

[0400] Obtaining a corresponding second through-hole echo gain according to the second through-hole reflection wave height;

[0401] Performing a linear fit on the second through-hole distance and the corresponding second through-hole reflection wave height to obtain a second through-hole DAC equivalent line;

[0402] Obtaining a corresponding third inclined groove echo gain according to the third inclined groove reflection wave height;

[0403] Obtaining a corresponding fourth inclined groove echo gain according to the fourth inclined groove reflection wave height;

[0404] Performing linear fitting on the fourth inclined groove distance and the corresponding fourth inclined groove reflection wave height to obtain a fourth inclined groove DAC equivalent line;

[0405] All the second circumferential groove echo gains, second through-hole echo gains, second through-hole DAC equivalent lines, third inclined groove echo gains, fourth inclined groove echo gains and fourth inclined groove DAC equivalent lines are aggregated to obtain scanning results of multiple second simulated defects.

[0406] Since the principle of solving the problem by the double-layer corrugated pipe defect detection device 600 based on ultrasonic guided waves is similar to the above method, the implementation of the double-layer corrugated pipe defect detection device 600 based on ultrasonic guided waves can refer to the implementation of the above method and will not be repeated here.

[0407] The systems, devices, modules, or units described in the above embodiments may be implemented by computer chips or entities, or by products having certain functions. A typical implementation device is a computer device. Specifically, the computer device may be, for example, a personal computer, a laptop computer, a cellular phone, a camera phone, a smartphone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or a combination of any of these devices.

[0408] In a typical example, a computer device specifically includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the method described above is implemented.

[0409] Reference below Figure 7 , which shows a schematic structural diagram of a computer device 700 suitable for implementing an embodiment of the present application.

[0410] like Figure 7 As shown, computer device 700 includes a central processing unit (CPU) 701, which can perform various appropriate tasks and processes according to a program stored in a read-only memory (ROM) 702 or a program loaded from a storage portion 708 into a random access memory (RAM) 703. Various programs and data required for the operation of system 700 are also stored in RAM 703. CPU 701, ROM 702, and RAM 703 are connected to each other via a bus 704. An input / output (I / O) interface 705 is also connected to bus 704.

[0411] The following components are connected to the I / O interface 705: an input section 706 including a keyboard, a mouse, and the like; an output section 707 including devices such as a cathode ray tube (CRT), a liquid crystal display (LCD), and a speaker; a storage section 708 including devices such as a hard disk; and a communication section 709 including a network interface card such as a LAN card or a modem. The communication section 709 performs communication processing via a network such as the Internet. A drive 710 is also connected to the I / O interface 705 as needed. Removable media 711, such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory, is installed in the drive 710 as needed, so that computer programs read therefrom can be installed in the storage section 708 as needed.

[0412] In particular, according to embodiments of the present invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of the present invention include a computer program product comprising a computer program tangibly embodied on a machine-readable medium, the computer program including program code for executing the methods illustrated in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication section 709 and / or installed from removable media 711.

[0413] Computer-readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. The information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media (transitory media), such as modulated data signals and carrier waves.

[0414] For the convenience of description, the above devices are described as being divided into various units according to their functions. Of course, when implementing this application, the functions of each unit can be implemented in the same or multiple software and / or hardware.

[0415] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0416] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0417] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 The steps for the function specified in one or more boxes.

[0418] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0419] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0420] The present application may be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform specific tasks or implement specific abstract data types. The present application may also be practiced in distributed computing environments where tasks are performed by remote processing devices connected through a communications network. In a distributed computing environment, program modules may be located in local and remote computer storage media, including storage devices.

[0421] The various embodiments in this specification are described in a progressive manner. Similar parts between the various embodiments can be referred to in conjunction with each other. Each embodiment focuses on the differences between the other embodiments. In particular, the system embodiments are generally similar to the method embodiments, so the description is relatively simple. For relevant parts, refer to the description of the method embodiments.

[0422] The foregoing is merely an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. A double-layer corrugated pipe defect detection method based on ultrasonic guided waves, characterized in that: The method comprises: Based on the scanning results of multiple first simulated defects of the outer layer inspection test block using the waveguide probe, an outer layer standard DAC curve group is obtained; based on the scanning results of multiple second simulated defects of the inner layer inspection test block using the waveguide probe, an inner layer standard DAC curve group is obtained; the outer layer inspection test block includes a first test block double-layer bellows and multiple first simulated defects arranged on the first test block double-layer bellows; wherein the first simulated defects include multiple first circumferential grooves in a preset first circumferential groove area, multiple first through holes in a preset first through hole area, and multiple first special grooves in a preset first special groove area, respectively arranged on the outer layer of the first test block double-layer bellows; the inner layer inspection test block includes a second test block double-layer bellows and multiple second simulated defects arranged on the second test block double-layer bellows; wherein the second simulated defects include multiple second circumferential grooves in a preset second circumferential groove area, multiple second through holes in a preset second through hole area, and multiple second special grooves in a preset second special groove area, respectively arranged on the inner layer of the second test block double-layer bellows; Based on the first circumferential scanning result of the outer layer of the target double-layer corrugated pipe using the waveguide probe and the outer layer standard DAC curve group, the outer layer defects of the target double-layer corrugated pipe are detected; based on the second circumferential scanning result of the inner layer of the target double-layer corrugated pipe using the waveguide probe and the inner layer standard DAC curve group, the inner layer defects of the target double-layer corrugated pipe are detected; The method of detecting outer layer defects of the target double-layer corrugated pipe based on the first circumferential scanning result of the outer layer of the target double-layer corrugated pipe using a waveguide probe and the outer layer standard DAC curve group includes: According to the first circumferential scanning result, a DAC detection curve of the outer circumferential groove and the through hole and a DAC detection curve of the outer inclined groove are obtained; According to the outer layer standard DAC curve group, a first outer layer standard DAC curve and a second outer layer standard DAC curve are obtained; Detect the corresponding first outer layer distance between the outer layer circumferential groove and the through hole DAC detection curve, whose height is greater than the corresponding height in the first outer layer standard DAC curve, and determine the first outer layer defect position based on the first outer layer distance and the corresponding first waveguide probe circumferential position, detect the corresponding second outer layer distance between the outer layer inclined groove DAC detection curve, whose height is greater than the corresponding height in the second outer layer standard DAC curve, and determine the second outer layer defect position based on the second outer layer distance and the corresponding second waveguide probe circumferential position, so as to complete the detection of the outer layer defects of the target double-layer corrugated pipe; The method of detecting inner layer defects of the target double-layer corrugated pipe based on the second circumferential scanning result of the inner layer of the target double-layer corrugated pipe using the waveguide probe and the inner layer standard DAC curve group includes: According to the second circumferential scanning result, a DAC detection curve of the inner circumferential groove and the through hole and a DAC detection curve of the inner inclined groove are obtained; According to the inner layer standard DAC curve group, a first inner layer standard DAC curve and a second inner layer standard DAC curve are obtained; Detect the corresponding first inner layer distance in the inner layer circumferential groove and through-hole DAC detection curve whose height is greater than the corresponding height in the first inner layer standard DAC curve, and determine the first inner layer defect position based on the first inner layer distance and the corresponding circumferential position of the third waveguide probe, detect the corresponding second inner layer distance in the inner layer inclined groove DAC detection curve whose height is greater than the corresponding height in the second inner layer standard DAC curve, and determine the second inner layer defect position based on the second inner layer distance and the corresponding circumferential position of the fourth waveguide probe, so as to complete the detection of inner layer defects of the target double-layer corrugated tube.

2. The method according to claim 1, characterized in that The first circumferential grooves are respectively arranged on the inner surface of a plurality of first preset wave crests and the outer surface of a plurality of first preset wave troughs of the outer layer of the double-layer bellows of the first test block.

3. The method according to claim 2, characterized in that The first through holes are respectively arranged at a plurality of the first preset wave crests and a plurality of the first preset wave troughs of the outer layer of the double-layer corrugated tube of the first test block.

4. The method according to claim 3, characterized in that The first special grooves include a plurality of first inclined grooves that form a first angle with the circumferential direction and a plurality of second inclined grooves that form a second angle with the circumferential direction; wherein the first angle and the second angle are acute angles.

5. The method according to claim 4, characterized in that The first inclined grooves are respectively arranged on the inner surface of the plurality of first preset wave crests and the outer surface of the plurality of first preset wave troughs of the outer layer of the double-layer corrugated tube of the first test block; The second inclined grooves are respectively arranged on the inner surface of the plurality of first preset wave peaks and the outer surface of the plurality of first preset wave troughs of the outer layer of the double-layer corrugated tube of the first test block.

6. The method according to claim 5, characterized in that The circumferential spacing distance between multiple first simulated defects arranged at the same wave crest of the double-layer corrugated tube of the first test block is greater than the preset first defect spacing distance; the circumferential spacing distance between multiple first simulated defects arranged at the same wave trough of the double-layer corrugated tube of the first test block is greater than the first defect spacing distance.

7. The method according to claim 1, characterized in that The second circumferential grooves are respectively arranged on the inner surface of a plurality of second preset wave crests and the outer surface of a plurality of second preset wave troughs of the inner layer of the double-layer bellows of the second test block.

8. The method according to claim 7, characterized in that The second through holes are respectively arranged at a plurality of the second preset wave crests and a plurality of the second preset wave troughs of the inner layer of the double-layer corrugated tube of the second test block.

9. The method according to claim 8, characterized in that The second special grooves include a plurality of third inclined grooves forming a third angle with the circumferential direction and a plurality of fourth inclined grooves forming a fourth angle with the circumferential direction; wherein the third angle and the fourth angle are acute angles.

10. The method according to claim 9, characterized in that The third inclined grooves are respectively arranged on the inner surface of multiple second preset peaks and the outer surface of multiple second preset troughs of the inner layer of the double-layer corrugated tube of the second test block; the fourth inclined grooves are respectively arranged on the inner surface of multiple second preset peaks and the outer surface of multiple second preset troughs of the inner layer of the double-layer corrugated tube of the second test block.

11. The method according to claim 10, characterized in that The circumferential spacing distance between multiple second simulated defects arranged at the same wave crest of the double-layer corrugated tube of the second test block is greater than the preset second defect spacing distance; the circumferential spacing distance between multiple second simulated defects arranged at the same wave trough of the double-layer corrugated tube of the second test block is greater than the second defect spacing distance.

12. The method according to claim 4, characterized in that The outer layer standard DAC curve group is obtained based on the scanning results of the plurality of the first simulated defects using the waveguide probe, including: According to the scanning results of the plurality of the first simulated defects, a first circumferential groove echo gain corresponding to each first circumferential groove, a first through-hole DAC equivalent line, a first through-hole echo gain corresponding to each first through-hole, a first inclined groove echo gain corresponding to each first inclined groove, a second inclined groove DAC equivalent line, and a second inclined groove echo gain corresponding to each second inclined groove are obtained; Obtaining a first outer layer standard DAC curve according to the first circumferential groove echo gain, the first through-hole DAC equivalent line and the first through-hole echo gain; Obtaining a second outer layer standard DAC curve according to the first inclined groove echo gain, the second inclined groove DAC equivalent line and the second inclined groove echo gain; The first outer layer standard DAC curve and the second outer layer standard DAC curve are clustered to obtain an outer layer standard DAC curve group.

13. The method according to claim 12, characterized in that The first outer layer standard DAC curve is obtained according to the first circumferential groove echo gain, the first through-hole DAC equivalent line and the first through-hole echo gain, including: Subtract the first through-hole echo gain from each of the first circumferential groove echo gains to obtain a plurality of first gain differences, and take an average of the plurality of first gain differences as a first average gain difference; Performing a gain operation on the first through-hole DAC equivalent line based on the first average gain difference to obtain a first quantitative line; A gain operation is performed on the first quantitative line based on a preset first optimized gain equivalent to obtain the first outer layer standard DAC curve.

14. The method according to claim 12, characterized in that The step of obtaining a second outer layer standard DAC curve according to the first inclined groove echo gain, the second inclined groove DAC equivalent line and the second inclined groove echo gain comprises: Subtract the corresponding second inclined groove echo gain from each first inclined groove echo gain to obtain a plurality of second gain differences, and take an average value of the plurality of second gain differences as a second average gain difference; Performing a gain operation on the second inclined groove DAC equivalent line based on the second average gain difference to obtain a second quantitative line; A gain operation is performed on the second quantitative line based on a preset second optimized gain equivalent to obtain the second outer layer standard DAC curve.

15. The method according to claim 4, characterized in that The inner layer standard DAC curve group is obtained based on the scanning results of the plurality of the second simulated defects using the waveguide probe, including: According to the scanning results of the plurality of second simulated defects, a second circumferential groove echo gain corresponding to each second circumferential groove, a second through-hole DAC equivalent line, a second through-hole echo gain corresponding to each second through-hole, a third inclined groove echo gain corresponding to each third inclined groove, a fourth inclined groove DAC equivalent line, and a fourth inclined groove echo gain corresponding to each fourth inclined groove are obtained; Obtaining a first inner layer standard DAC curve according to the second circumferential groove echo gain, the second through-hole DAC equivalent line and the second through-hole echo gain; Obtaining a second inner layer standard DAC curve according to the third inclined groove echo gain, the fourth inclined groove DAC equivalent line and the fourth inclined groove echo gain; The first inner layer standard DAC curve and the second inner layer standard DAC curve are clustered to obtain an inner layer standard DAC curve group.

16. The method according to claim 15, characterized in that The first inner layer standard DAC curve is obtained according to the second circumferential groove echo gain, the second through-hole DAC equivalent line and the second through-hole echo gain, including: Subtract the corresponding second through-hole echo gain from each second circumferential groove echo gain to obtain a plurality of third gain differences, and take an average of the plurality of third gain differences as a third average gain difference; Performing a gain operation on the second through-hole DAC equivalent line based on the third average gain difference to obtain a third quantitative line; A gain operation is performed on the third quantitative line based on a preset third optimized gain equivalent to obtain the first inner layer standard DAC curve.

17. The method according to claim 15, characterized in that The step of obtaining a second inner layer standard DAC curve according to the third inclined groove echo gain, the fourth inclined groove DAC equivalent line and the fourth inclined groove echo gain comprises: Subtract the corresponding fourth inclined groove echo gain from each third inclined groove echo gain to obtain a plurality of fourth gain differences, and take an average of the plurality of fourth gain differences as a fourth average gain difference; Performing a gain operation on the fourth inclined groove DAC equivalent line based on the fourth average gain difference to obtain a fourth quantitative line; A gain operation is performed on the fourth quantitative line based on a preset fourth optimized gain equivalent to obtain the second inner layer standard DAC curve.

18. The method according to claim 4, characterized in that Further including: Before obtaining the outer layer standard DAC curve group based on the scanning results of the plurality of the first simulated defects using the waveguide probe, A waveguide probe is axially arranged at the non-sealing area of ​​the straight section of the outer end of the double-layer bellows of the first test block, and the waveguide probe is circumferentially moved until the first circumferential groove reflection wave heights of all first circumferential grooves, the first through hole distances of all first through holes and the waveguide probe, and the first through hole reflection wave heights are collected; The waveguide probe is set at the non-sealing area of ​​the straight section of the outer end of the double-layer bellows of the first test block in the direction of the first angle with the axial direction, and the waveguide probe is moved circumferentially until the first inclined groove reflection wave heights of all the first inclined grooves are collected; The waveguide probe is set at the non-sealing area of ​​the straight section of the outer end of the double-layer bellows of the first test block in the direction of the second angle with the axial direction, and the waveguide probe is moved circumferentially until the distance between all the second inclined grooves and the second inclined grooves of the waveguide probe and the second inclined groove reflection wave height are collected; All of the first circumferential groove reflection wave heights, the first through-hole distance, the first through-hole reflection wave height corresponding to the first through-hole distance, the first inclined groove reflection wave height, the second inclined groove distance and the second inclined groove reflection wave height corresponding to the second inclined groove distance are integrated into the scanning result of the plurality of the first simulated defects.

19. The method according to claim 9, characterized in that The method further comprises: Before obtaining the inner layer standard DAC curve group based on the scanning results of the plurality of the second simulated defects using the waveguide probe, A waveguide probe is axially arranged at the sealing welding area of ​​the straight section of the outer end of the double-layer bellows of the second test block, and the waveguide probe is circumferentially moved until the second circumferential groove reflection wave heights of all second circumferential grooves, the second through hole distances of all second through holes and the waveguide probe, and the second through hole reflection wave heights are collected; The waveguide probe is arranged at the sealing welding area of ​​the straight section of the outer layer end of the double-layer bellows of the second test block in a direction forming the third angle with the axial direction, and the waveguide probe is moved circumferentially until the third inclined groove reflection wave height of all the third inclined grooves is collected; The waveguide probe is set at the sealing welding area of ​​the straight section of the outer end of the second test block double-layer bellows in a direction that forms the fourth angle with the axial direction, and the waveguide probe is moved circumferentially until the fourth inclined groove distances between all the fourth inclined grooves and the waveguide probe and the fourth inclined groove reflection wave heights are collected; All of the second circumferential groove reflection wave heights, the second through-hole distance, the second through-hole reflection wave height corresponding to the second through-hole distance, the third inclined groove reflection wave height, the fourth inclined groove distance and the fourth inclined groove reflection wave height corresponding to the fourth inclined groove distance are integrated into the scanning result of multiple second simulated defects.

20. The method according to claim 1, characterized in that The outer circumferential groove and through hole DAC detection curve is obtained by axially setting the waveguide probe in the non-sealing area of ​​the straight section of the outer end of the target double-layer corrugated pipe, and moving the waveguide probe along the circumference of the target double-layer corrugated pipe for one circle.

21. The method according to claim 4, characterized in that The outer layer inclined groove DAC detection curve is obtained by setting the waveguide probe in the direction of the first angle with the axial direction in the non-welding area of ​​the straight section of the outer layer end of the target double-layer corrugated pipe, and moving the waveguide probe along the circumference of the target double-layer corrugated pipe for one circle.

22. The method according to claim 1, characterized in that The inner circumferential groove and through hole DAC detection curve is obtained by axially setting the waveguide probe in the sealing area of ​​the straight section of the outer end of the target double-layer corrugated pipe, and moving the waveguide probe along the circumference of the target double-layer corrugated pipe for one circle.

23. The method according to claim 9, characterized in that The inner layer inclined groove DAC detection curve is obtained by setting the waveguide probe in the direction of the third angle with the axial direction at the sealing area of ​​the straight section of the outer layer end of the target double-layer corrugated pipe, and moving the waveguide probe along the circumference of the target double-layer corrugated pipe for one circle.

24. The method according to claim 1, characterized in that The inner layer circumferential groove and through hole DAC detection curve is obtained by axially setting the waveguide probe in the non-sealing area of ​​the straight section of the inner layer end of the target double-layer corrugated pipe, and moving the waveguide probe along the circumference of the target double-layer corrugated pipe for one circle.

25. The method according to claim 9, characterized in that The inner layer inclined groove DAC detection curve is obtained by setting the waveguide probe in the direction of the third angle with the axial direction in the non-welding area of ​​the straight section of the inner layer end of the target double-layer corrugated pipe, and moving the waveguide probe along the circumference of the target double-layer corrugated pipe for one circle.

26. The method according to claim 12, characterized in that The step of integrating all the first circumferential groove reflection wave heights, the first through-hole distance, the first through-hole reflection wave height corresponding to the first through-hole distance, the first inclined groove reflection wave height, the second inclined groove distance, and the second inclined groove reflection wave height corresponding to the second inclined groove distance into a scanning result of the plurality of the first simulated defects includes: Obtaining a corresponding first circumferential groove echo gain according to the first circumferential groove reflection wave height; Obtaining a corresponding first through-hole echo gain according to the first through-hole reflection wave height; Performing a linear fit between the first through hole distance and the corresponding first through hole reflection wave height to obtain a first through hole DAC equivalent line; According to the first inclined groove reflection wave height, obtaining the corresponding first inclined groove echo gain; According to the reflection wave height of the second inclined groove, a corresponding second inclined groove echo gain is obtained; Performing a linear fit on the second inclined groove distance and the corresponding second inclined groove reflection wave height to obtain a second inclined groove DAC equivalent line; All of the first circumferential groove echo gains, first through-hole echo gains, first through-hole DAC equivalent lines, first inclined groove echo gains, second inclined groove echo gains, and second inclined groove DAC equivalent lines are aggregated to obtain scanning results of the plurality of the first simulated defects.

27. The method according to claim 15, characterized in that The step of integrating all the second circumferential groove reflection wave heights, the second through-hole distance, the second through-hole reflection wave height corresponding to the second through-hole distance, the third inclined groove reflection wave height, the fourth inclined groove distance, and the fourth inclined groove reflection wave height corresponding to the fourth inclined groove distance into a scanning result of the plurality of second simulated defects includes: According to the reflection wave height of the second circumferential groove, a corresponding second circumferential groove echo gain is obtained; Obtaining a corresponding second through-hole echo gain according to the second through-hole reflection wave height; Performing a linear fit on the second through hole distance and the corresponding second through hole reflection wave height to obtain a second through hole DAC equivalent line; According to the third inclined groove reflection wave height, obtaining a corresponding third inclined groove echo gain; According to the fourth inclined groove reflection wave height, a corresponding fourth inclined groove echo gain is obtained; Performing linear fitting on the fourth inclined groove distance and the corresponding fourth inclined groove reflection wave height to obtain a fourth inclined groove DAC equivalent line; All of the second circumferential groove echo gains, second through-hole echo gains, second through-hole DAC equivalent lines, third inclined groove echo gains, fourth inclined groove echo gains and fourth inclined groove DAC equivalent lines are aggregated to obtain scanning results of multiple second simulated defects.

28. A test block, characterized in that: It includes an outer layer test block and an inner layer test block; The outer layer inspection test block includes a first test block double-layer bellows and a plurality of first simulated defects arranged on the first test block double-layer bellows; Wherein the first simulated defect comprises a plurality of first circumferential grooves in a preset first circumferential groove zone, a plurality of first through holes in a preset first through hole zone and a plurality of first special grooves in a preset first special groove zone, respectively arranged on the outer layer of the double-layer bellows of the first test block; the first circumferential grooves are respectively arranged on the inner surface of a plurality of first preset wave crests and the outer surface of a plurality of first preset wave troughs of the outer layer of the double-layer bellows of the first test block; the first through holes are respectively arranged on a plurality of first preset wave crests and a plurality of first preset wave troughs of the outer layer of the double-layer bellows of the first test block; the first special grooves comprise a plurality of first inclined grooves at a first angle to the circumferential direction and a plurality of second inclined grooves at a second angle to the circumferential direction; the first angle and the second angle are acute angles; The inner layer inspection test block includes a second test block double-layer bellows and a plurality of second simulated defects arranged on the second test block double-layer bellows; The second simulated defect includes a plurality of second circumferential grooves in a preset second circumferential groove area, a plurality of second through holes in a preset second through hole area, and a plurality of second special grooves in a preset second special groove area, respectively arranged in the inner layer of the double-layer bellows of the second test block; the second circumferential grooves are respectively arranged on the inner surface of a plurality of second preset wave peaks and the outer surface of a plurality of second preset wave troughs of the inner layer of the double-layer bellows of the second test block; the second through holes are respectively arranged on a plurality of second preset wave peaks and a plurality of second preset wave troughs of the inner layer of the double-layer bellows of the second test block; the second special grooves include a plurality of third inclined grooves having a third angle with the circumferential direction and a plurality of fourth inclined grooves having a fourth angle with the circumferential direction; the third angle and the fourth angle are acute angles.

29. A double-layer corrugated pipe defect detection device based on ultrasonic guided waves, characterized in that: The device comprises: A standard DAC curve generation module, for obtaining an outer layer standard DAC curve group based on the scanning results of multiple first simulated defects of an outer layer inspection test block using a waveguide probe; and obtaining an inner layer standard DAC curve group based on the scanning results of multiple second simulated defects of an inner layer inspection test block using a waveguide probe; the outer layer inspection test block includes a first test block double-layer bellows and multiple first simulated defects arranged on the first test block double-layer bellows; wherein the first simulated defects include multiple first circumferential grooves in a preset first circumferential groove area, multiple first through holes in a preset first through hole area, and multiple first special grooves in a preset first special groove area, respectively arranged on the outer layer of the first test block double-layer bellows; the inner layer inspection test block includes a second test block double-layer bellows and multiple second simulated defects arranged on the second test block double-layer bellows; wherein the second simulated defects include multiple second circumferential grooves in a preset second circumferential groove area, multiple second through holes in a preset second through hole area, and multiple second special grooves in a preset second special groove area, respectively arranged on the inner layer of the second test block double-layer bellows; A bellows defect detection module, for detecting outer layer defects of the target double-layer bellows based on a first circumferential scanning result of the outer layer of the target double-layer bellows using a waveguide probe and the outer layer standard DAC curve group; and for detecting inner layer defects of the target double-layer bellows based on a second circumferential scanning result of the inner layer of the target double-layer bellows using a waveguide probe and the inner layer standard DAC curve group; The method of detecting outer layer defects of the target double-layer corrugated pipe based on the first circumferential scanning result of the outer layer of the target double-layer corrugated pipe using a waveguide probe and the outer layer standard DAC curve group includes: According to the first circumferential scanning result, a DAC detection curve of the outer circumferential groove and the through hole and a DAC detection curve of the outer inclined groove are obtained; According to the outer layer standard DAC curve group, a first outer layer standard DAC curve and a second outer layer standard DAC curve are obtained; Detect the corresponding first outer layer distance between the outer layer circumferential groove and the through hole DAC detection curve, whose height is greater than the corresponding height in the first outer layer standard DAC curve, and determine the first outer layer defect position based on the first outer layer distance and the corresponding first waveguide probe circumferential position, detect the corresponding second outer layer distance between the outer layer inclined groove DAC detection curve, whose height is greater than the corresponding height in the second outer layer standard DAC curve, and determine the second outer layer defect position based on the second outer layer distance and the corresponding second waveguide probe circumferential position, so as to complete the detection of the outer layer defects of the target double-layer corrugated pipe; The method of detecting inner layer defects of the target double-layer corrugated pipe based on the second circumferential scanning result of the inner layer of the target double-layer corrugated pipe using the waveguide probe and the inner layer standard DAC curve group includes: According to the second circumferential scanning result, a DAC detection curve of the inner circumferential groove and the through hole and a DAC detection curve of the inner inclined groove are obtained; According to the inner layer standard DAC curve group, a first inner layer standard DAC curve and a second inner layer standard DAC curve are obtained; Detect the corresponding first inner layer distance in the inner layer circumferential groove and through-hole DAC detection curve whose height is greater than the corresponding height in the first inner layer standard DAC curve, and determine the first inner layer defect position based on the first inner layer distance and the corresponding circumferential position of the third waveguide probe, detect the corresponding second inner layer distance in the inner layer inclined groove DAC detection curve whose height is greater than the corresponding height in the second inner layer standard DAC curve, and determine the second inner layer defect position based on the second inner layer distance and the corresponding circumferential position of the fourth waveguide probe, so as to complete the detection of inner layer defects of the target double-layer corrugated tube.

30. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the method according to any one of claims 1 to 27 is implemented.

31. A computer readable medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 27 is implemented.

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