Cable strength detection method and system

Abstract

The invention discloses a cable strength detection method and system, relates to the technical field of cable detection, and solves the technical problems that the metal cable detection process is not standard, the defect positioning and quantification precision is low, the contradiction between the non-metal cable detection efficiency and precision is prominent, and microscopic verification is lacked. A high-frequency arc-shaped phased array probe, a bicrystal oblique TOFD probe and an oil-based high-viscosity coupling agent are adopted, a layered focusing technology is combined, laser ultrasonic non-contact detection and ultrasonic microscope high-resolution imaging are adopted for a non-metal cable, and spiral scanning and circumferential fixed-point scanning are combined, so that the defect omission ratio in the circumferential direction is reduced; the abnormal region judgment takes a calibration test block as a reference, the misjudgment rate is reduced, the authenticity is verified through coarse scanning and locking of a core region, fine scanning and acquisition of a high-resolution image and multi-angle imaging, the defect type judgment basis is clear, and the misjudgment rate is reduced.

Description

Technical Field

[0001] This invention relates to the field of cable testing technology, specifically to a method and system for testing cable strength. Background Technology

[0002] As a core load-bearing component in fields such as lifting and transportation, ship mooring, marine engineering, and construction, the mechanical properties and structural integrity of cables directly determine operational safety. For example, the breakage of a crane cable may cause heavy objects to fall, and the failure of a ship's mooring cable may cause the ship to drift and collide. Therefore, the need for defect detection of cables runs through their entire life cycle.

[0003] Current cable inspection technologies in the industry mainly focus on two types of materials: metal cables and non-metal cables. However, due to limitations in technical approaches and equipment compatibility, a systematic classification and inspection scheme has not yet been formed. For the inspection of metal cables, traditional ultrasonic testing suffers from poor probe-to-cable-surface contact, a single scanning method, and low quantitative accuracy of defects. For the inspection of non-metal cables, infrared thermal imaging or ordinary ultrasonic testing are mostly used. Infrared thermal imaging can only identify surface or near-surface aging defects and is not sensitive enough to internal fiber micro-fractures, core layer delamination, and other defects. Ordinary ultrasonic testing requires the use of liquid coupling agents, which can easily penetrate into the fiber interior and cause material damage. In addition, the scanning step size is too large, making it difficult to capture micro-voids and micro-inclusions with a size of <50μm. Furthermore, there is a lack of a connection process between macroscopic and microscopic aspects. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a method and system for testing cable strength, which solves the problems of non-standard testing procedures for metal cables, low accuracy in defect location and quantification, prominent contradiction between efficiency and accuracy in testing non-metallic cables, and lack of microscopic verification.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for testing cable strength, which specifically includes the following steps: Step 1: Obtain the cable to be tested, determine the cable material, and classify it into metal cable and non-metal cable based on the cable material. Step 2: Clean, straighten and mark the metal cables in sequence, determine the equipment selection of the phased array system, and use a combination of spiral scanning and circumferential fixed-point scanning to scan the defective areas of the metal cables. Step 3: For the identified defect area, use ultrasonic mode analysis to extract the amplitude-time curve of a single detection point in the defect area, calculate the defect depth, and compare it with the first standard allowable value to generate metal cable detection information. Step 4: Clean and flatten the surface of the non-metallic cable, and set up a detection system including a laser ultrasonic module, an ultrasonic microscope module and a motion control platform. The laser ultrasonic module emits pulsed laser, the interferometer receives the defect reflection wave signal, and determines the suspected defect area and the core area. Step 5: Extract the signal features corresponding to the amplitude-time curve of a single detection point in the core area and classify the defect type. At the same time, calculate the defect depth and compare it with the second standard allowable value to generate non-metallic cable detection information.

[0006] As a further aspect of the present invention, the cable is classified according to its material as follows: cables with metal as their core material are classified as metal cables, and cables with natural or synthetic fibers or composite materials as their core material are classified as non-metal cables.

[0007] As a further aspect of the present invention, the method for determining the equipment selection of the phased array system is as follows: The metal cable is acquired and pre-treated, including cleaning, straightening, and marking. Cleaning involves blowing away surface dust with high-pressure air and wiping away oil and rust with alcohol or a special cleaning agent. Straightening involves slightly straightening the cable with a special fixture to ensure the surface of the detection area is flat. Marking involves dividing the detection unit according to the length and circumference of the cable. A high-frequency arc array probe is selected as the phased array probe, and a dual-crystal angle probe is selected as the TOFD probe. An oil-based high-viscosity coupling agent is also used.

[0008] As a further aspect of the present invention, the method for scanning defective areas of metal cables is as follows: For spiral scanning, the probe is moved along the length of the cable while slowly rotating around the circumference of the cable to achieve full coverage scanning of the entire cable and generate a planar view. For circumferential fixed-point scanning, abnormal areas with abrupt changes in reflected waves are obtained in the planar view. Then, the probe is continuously scanned around the circumference to generate a cross-sectional view. At the same time, the image appearance of the area corresponding to the abnormal area in the cross-sectional view is identified. If a certain area shows continuous strong reflected waves and the amplitude exceeds the amplitude of the standard defect in the calibration block, it is judged to be a defect area.

[0009] As a further aspect of the present invention, the method for generating metal cable detection information is as follows: Draw a line through the center of the probe across the abnormal area, and then obtain the incident angle of the probe wedge. The longitudinal wave velocity c1 of the wedge and the longitudinal wave velocity c2 of the metal cable are determined according to the formula... =(c1 / c2)× Calculated Furthermore, it was deduced that the angle of refraction... ; The ultrasonic A-scan signal of the defect region is extracted, and the A-scan signal represents the amplitude-time curve of a single detection point, which is the raw data. The S-wave diffraction wave at the upper end of the defect and the P-wave diffraction wave at the lower end are identified, and the time difference between the two is calculated and denoted as . According to the formula, defect depth = (c² × ... ) / (2×cos The defect depth is calculated. The obtained defect depth is compared with the corresponding first standard allowable value, which is set by the operator. If the defect depth is less than or equal to the first standard allowable value, it is considered qualified. Conversely, if the defect depth is greater than the first standard allowable value, it is considered unqualified and the corresponding metal cable inspection information is generated simultaneously.

[0010] As a further aspect of the present invention, the specific method for constructing the detection system is as follows: The laser ultrasound module emits a laser at a 45° incident angle to irradiate the cable surface. The receiving interferometer is positioned directly above the cable surface. The ultrasonic microscope module aligns the microscope probe with the cable scanning area, maintaining a distance of 0.5-1 mm or close to the water film between the probe and the cable surface. The motion control platform uses an XYZ three-axis electric platform to drive the cable or probe to perform line scanning and surface scanning. Line scanning is performed along the length of the cable, while surface scanning covers the circumference of the cable. The scan is performed once every 10° of rotation to ensure no blind spots.

[0011] As a further aspect of the present invention, the method for determining suspected defective areas is as follows: The laser ultrasonic module emits pulsed lasers to generate a thermoelastic effect on the surface of the cable and excite longitudinal and transverse ultrasonic signals. At the same time, the laser interferometer receives and identifies the two types of key signals, performs line scanning along the length of the cable, collects one set of signals every 10 mm, records the position of the defect reflection wave, and marks the corresponding area as a suspected defect area. The suspected defect area is acquired, and a rapid coarse scan is performed with low resolution and a large scanning range to obtain a planar top view and a cross-sectional side view. Then, the lateral boundary of the suspected defect is determined by the planar top view, and the depth distribution of the defect is preliminarily determined by the cross-sectional side view. The core area of ​​the suspected defect area is marked.

[0012] As a further aspect of the present invention, the method for classifying defect types is as follows: Extract the signal features corresponding to the amplitude-time curve of a single detection point. If the signal features have two consecutive reflected waves with medium amplitude, they are classified as microcracks. If the signal features have one strong reflected wave with high amplitude, they are classified as micro-inclusions. If the signal features have one strong reflected wave with no subsequent signal, they are classified as micro-voids.

[0013] As a further aspect of the present invention, the method for generating non-metallic cable detection information is as follows: Obtain the acoustic path difference between the upper and lower endpoints of the defect and the sample surface in the cross-sectional side view. , specific Given the time difference between the reflected waves at the upper and lower ends of the defect, the longitudinal wave velocity c3 of the non-metallic cable is obtained. According to the formula: Defect Depth = (c3 × ... The corresponding defect depth is calculated by dividing the result by 2. The obtained defect depth is compared with the corresponding second standard allowable value, and the specific value of the second standard allowable value is set by the operator. If the defect depth is less than or equal to the second standard allowable value, it is judged as qualified. Conversely, if the defect depth is greater than the second standard allowable value, it indicates that it exceeds the standard and is judged as unqualified. At the same time, the corresponding non-metallic cable inspection information is generated.

[0014] A cable strength testing system, comprising: The cable information acquisition module is used to acquire the cable to be tested, determine the cable material of the cable to be tested, and classify it into metal cable and non-metal cable according to the cable material, and transmit the information of the two separately. The metal cable inspection and analysis module is used to clean, straighten, and mark the metal cable sequentially, and to determine the equipment selection for the phased array system. It uses a combination of spiral scanning and circumferential fixed-point scanning to scan the defect area of ​​the metal cable. For the identified defect area, ultrasonic mode analysis is used to extract the amplitude-time curve of a single detection point in the defect area and calculate the defect depth. At the same time, it is compared with the first standard allowable value to generate metal cable inspection information and transmit it to the inspection information output module. The non-metallic cable inspection and analysis module is used to perform surface cleaning and leveling of non-metallic cables. It is equipped with an inspection system including a laser ultrasonic module, an ultrasonic microscope module, and a motion control platform. The laser ultrasonic module emits pulsed lasers, receives defect reflection wave signals from the interferometer, and identifies suspected defect areas. Based on the characteristics corresponding to the amplitude-time curve of a single detection point in the core area, the defect type is classified and the defect depth is calculated. At the same time, it is compared with the second standard allowable value to generate non-metallic cable inspection information and transmit it to the inspection information output module. The detection information output module is used to display the acquired detection information of metal cables and non-metal cables to the corresponding management personnel.

[0015] This invention provides a method and system for testing cable strength. Compared with the prior art, it has the following advantages: This invention targets metal cables by employing a high-frequency arc-shaped phased array probe, a dual-crystal oblique TOFD probe, and an oil-based high-viscosity coupling agent, combined with layered focusing technology, to solve the problems of poor probe fit and signal attenuation in traditional probes. For non-metallic cables, it employs laser ultrasonic non-contact detection and high-resolution imaging with an ultrasonic microscope to solve the problem of insufficient sensitivity of traditional infrared or ordinary ultrasound to internal micro-defects.

[0016] This invention combines spiral scanning and circumferential fixed-point scanning to reduce the missed detection rate of defects in the circumferential direction; the judgment of abnormal areas is based on the calibration test block to reduce the false judgment rate. The core area is locked by coarse scanning, high-resolution images are collected by fine scanning, and the authenticity is verified by multi-angle imaging. The basis for judging the defect type is clear, and the false judgment rate is reduced. Attached Figure Description

[0017] Figure 1 This is a diagram illustrating the steps and methods of the present invention; Figure 2 This is a system block diagram of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] First Embodiment Please see Figure 1 This application provides a method for testing cable strength, which specifically includes the following steps: Step 1: Obtain the corresponding cable to be tested and its corresponding cable material. Then, classify the cable into metal cables and non-metal cables according to its material. Metal cables are defined as those with metal materials as the core, including steel wire rope, steel strand, copper cable and aluminum alloy cable. Non-metal cables are defined as those with natural or synthetic fibers and composite materials as the core, including polyester cable, nylon cable, polypropylene cable and aramid cable. Step 2: Analyze and inspect the classified metal cables. Obtain the metal cables and pre-treat them, including cleaning, straightening, and marking. Cleaning involves blowing away surface dust with high-pressure air and wiping away oil and rust with alcohol or a special cleaning agent. Straightening involves slightly straightening the cables with a special clamp to ensure a smooth surface in the inspection area. Marking involves dividing the inspection area into units along the cable length and circumference, such as 100mm per unit and 8 equal parts around the circumference, to facilitate subsequent defect location. A high-frequency arc array probe is selected as the phased array probe, and a dual-crystal angled probe is selected as the TOFD probe, along with an oil-based high-viscosity coupling agent, such as industrial ultrasonic coupling grease. Next, the parameters of the phased array system are set. Specifically, the fan-shaped scanning angle is set from 0° to 70°, and focusing is performed in layers according to the cable radius. For example, for a cable with a diameter of 20mm, the focusing depth is set to 5mm, 10mm, and 15mm. A combination of helical scanning and circumferential fixed-point scanning is used for analysis. For helical scanning, the probe is moved along the length of the cable at a speed of 5-10mm / s, while simultaneously rotating slowly around the circumference of the cable by 45° for every 10mm movement, achieving full coverage scanning of the entire cable and generating a planar view. The planar view shows defects in the length-circumference area. The probe is positioned to perform a circumferential fixed-point scan, acquiring the abnormal area found in the planar view. This abnormal area indicates a sudden change in reflected wave. Then, the probe is continuously scanned around the circumference to generate a cross-sectional view, which shows the distribution of defects in the circumferential-depth direction. At the same time, the image appearance of the area corresponding to the abnormal area in the cross-sectional view is identified. If a certain area shows continuous strong reflected waves with an amplitude exceeding the amplitude of the standard defect in the calibration block, it is identified as a defect area. Its axial length and circumferential position are marked, and the length position is fixed. This indicates that the phased array ultrasound has detected an abnormality, and the ultrasound mode is switched at this time.

[0020] Step 3: For the ultrasonic mode, determine the depth range corresponding to the abnormal area based on the obtained cross-sectional view, adjust the position of the phased array ultrasonic probe and calculate the specific defect depth, and simultaneously determine the defect level. The specific processing method is as follows: Draw a line through the center of the probe across the abnormal area, and then obtain the incident angle of the probe wedge. The longitudinal wave velocity c1 of the wedge and the longitudinal wave velocity c2 of the metal cable, and the specific incident angle. The angle of incidence corresponds to the angle between the wedge and the surface being inspected, and is usually specified by the probe manufacturer. The longitudinal wave velocity c1 can be found in the material handbook or measured using an ultrasonic velocimeter. The longitudinal wave velocity c2 needs to be determined based on the cable material, according to the formula... =(c1 / c2)× Calculated Furthermore, it was deduced that the angle of refraction... ; The ultrasonic A-scan signal of the defect region is extracted, and the A-scan signal represents the amplitude-time curve of a single detection point, which is the raw data. The S-wave diffraction wave at the upper end of the defect and the P-wave diffraction wave at the lower end are identified, and the time difference between the two is calculated and denoted as . If noise exists in the signal here, wavelet transform denoising or dynamic filtering is required to ensure clear peak positions. According to the formula: Defect depth = (c² × ... ) / (2×cos The defect depth is calculated, and then the defect depth and refraction angle are combined using the formula: Spacing = Defect Depth × 2 × tan The corresponding adjustment interval is calculated, and the position is fine-tuned based on it. The obtained defect depth is compared with the corresponding first standard allowable value, which is set by the operator. If the defect depth is less than or equal to the first standard allowable value, it is considered qualified. Conversely, if the defect depth is greater than the first standard allowable value, it is considered unqualified and the corresponding metal cable inspection information is generated simultaneously.

[0021] Step 4: Analyze and test the classified non-metallic cables. Obtain the non-metallic cables and perform pretreatment, including surface cleaning and smoothing. Specifically, the surface of non-metallic cables is prone to oil, dust, or fiber debris; therefore, wipe the surface with anhydrous ethanol to avoid corrosion and remove impurities. If there are obvious bumps or roughness on the surface, gently sand it with fine sandpaper to remove only surface burrs without damaging the internal fibers, ensuring the stability of laser incident and ultrasonic reception. Simultaneously, build a corresponding detection system, including a laser-ultrasound module, an ultrasonic microscope module, and a motion control platform. Specifically, the laser-ultrasound module emits a laser at a 45° incident angle to irradiate the cable surface, and the receiving interferometer is directly facing the cable surface (meaning the angle between the receiving interferometer and the transmitting end is 90°). The ultrasonic microscope module aligns the microscope probe with the cable scanning area, controlling the distance between the probe and the cable surface to be 0.5-1mm or close to the waterline. For testing the cross-section of a cable, the cable needs to be cut and the cross-section ground to make the probe parallel to the cross-section. The motion control platform uses an XYZ three-axis electric platform to drive the cable or probe to perform line scanning and surface scanning. The line scanning direction is along the length of the cable, and the step size is 100-500μm, which is adjusted according to the possible distribution density of defects. The surface scanning covers the circumference of the cable and is performed once every 10° rotation to ensure no blind spots. The laser ultrasonic module emits pulsed lasers to generate a thermoelastic effect on the surface of the cable and excite longitudinal and transverse ultrasonic signals. At the same time, the laser interferometer receives two types of key signals and performs identification and analysis. Line scanning is performed along the length of the cable, and one set of signals is collected every 10mm. The position of the defect reflection wave is recorded, and the corresponding area is marked as a suspected defect area. The defect reflection wave represents the reflection wave generated when the ultrasound encounters internal fiber breakage or delamination. Then, microscopic verification is performed using an ultrasonic microscope. The suspected defect area is acquired and quickly coarsely scanned with low resolution and a large scanning range, such as scanning the suspected area and its surrounding 1-2 mm, to obtain a planar top view and a cross-sectional side view. Then, the lateral boundary of the suspected defect is determined by the planar top view, such as its position and range in the xy plane. The depth distribution of the defect is initially determined by the cross-sectional side view, such as its distance from the sample surface and whether it penetrates through. The core area of ​​the suspected defect area is marked. For the obtained core area, a fine scan is performed using high-resolution parameters, acquiring A-scan signals and high-resolution cross-sectional side views. The A-scan signal represents the amplitude-time curve of a single detection point and is the raw data. At the same time, the core area is scanned from different angles. If the imaging in all directions shows a consistent defect morphology, the authenticity of the defect is further confirmed. Step 5: Based on the A-scan signal corresponding to the core area and to determine the defect type, extract the amplitude-time curve signal features of a single detection point. If the A-scan has two consecutive reflected waves with moderate amplitude, it is classified as a microcrack. If the A-scan has one strong reflected wave with high amplitude, it is classified as a micro-inclusion. If the A-scan has one strong reflected wave with no subsequent signal, it is classified as a micro-void. Then, based on the ultrasonic propagation law, calculate the critical dimensions of the defect and obtain the acoustic path difference between the upper and lower endpoints of the defect and the sample surface in the cross-sectional side view. , specific Given the time difference between the reflected waves at the upper and lower ends of the defect, the longitudinal wave velocity c3 of the non-metallic cable is obtained. According to the formula: Defect Depth = (c3 × ... The corresponding defect depth is calculated by dividing the result by 2. The obtained defect depth is compared with the corresponding second standard allowable value, and the specific value of the second standard allowable value is set by the operator. If the defect depth is less than or equal to the second standard allowable value, it is judged as qualified. Conversely, if the defect depth is greater than the second standard allowable value, it indicates that it exceeds the standard and is judged as unqualified. At the same time, the corresponding non-metallic cable inspection information is generated.

[0022] Second Embodiment Please see Figure 2 This application provides a cable strength testing system, including: a cable information acquisition module, a metal cable testing and analysis module, a non-metal cable testing and analysis module, and a testing information output module, and combined with... Figure 2 It can be seen that the information between the above functional modules is transmitted in one direction only; The cable information acquisition module is used to acquire the cable to be tested, determine the cable material of the cable to be tested, and classify it into metal cable and non-metal cable according to the cable material, and transmit the information of the two separately. The specific processing method is the same as the processing process in step one. The metal cable inspection and analysis module is used to clean, straighten, and mark the metal cable in sequence, and to determine the equipment selection of the phased array system. It uses a combination of spiral scanning and circumferential fixed-point scanning to scan the defect area of ​​the metal cable. For the identified defect area, ultrasonic mode analysis is used to extract the amplitude-time curve of a single detection point in the defect area and calculate the defect depth. At the same time, it is compared with the first standard allowable value to generate metal cable inspection information and transmit it to the inspection information output module. The specific processing method is the same as the processing process in steps two and three. The non-metallic cable inspection and analysis module is used to perform surface cleaning and flattening on non-metallic cables. It is equipped with an inspection system including a laser ultrasonic module, an ultrasonic microscope module, and a motion control platform. The laser ultrasonic module emits pulsed lasers, receives defect reflection wave signals from the interferometer, and identifies suspected defect areas. It extracts the signal features corresponding to the amplitude-time curve of a single detection point in the core area and classifies the defect type. At the same time, it calculates the defect depth and compares it with the second standard allowable value to generate non-metallic cable inspection information and transmits it to the inspection information output module. The specific processing method is the same as the processing in steps four and five. The detection information output module is used to display the acquired detection information of metal cables and non-metal cables to the corresponding management personnel.

[0023] Some of the data in the above formulas are numerical calculations with dimensions removed, and the contents not described in detail in this specification are all prior art known to those skilled in the art.

[0024] The above embodiments are only used to illustrate the technical methods of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical methods of the present invention without departing from the spirit and scope of the technical methods of the present invention.

Claims

1. A method for testing cable strength, characterized in that, The method specifically includes the following steps: Step 1: Obtain the cable to be tested, determine the cable material, and classify it into metal cable and non-metal cable according to the cable material. Step 2: Clean, straighten and mark the metal cables in sequence, determine the equipment selection of the phased array system, and use a combination of spiral scanning and circumferential fixed-point scanning to scan the defective areas of the metal cables. Step 3: For the identified defect area, use ultrasonic mode analysis to extract the amplitude-time curve of a single detection point in the defect area, calculate the defect depth, and compare it with the first standard allowable value to generate metal cable detection information. Step 4: Clean and flatten the surface of the non-metallic cable, and set up a detection system including a laser ultrasonic module, an ultrasonic microscope module and a motion control platform. The laser ultrasonic module emits pulsed laser, the interferometer receives the defect reflection wave signal, and determines the suspected defect area and the core area. Step 5: Extract the signal features corresponding to the amplitude-time curve of a single detection point in the core area and classify the defect type. At the same time, calculate the defect depth and compare it with the second standard allowable value to generate non-metallic cable detection information.

2. The cable strength testing method according to claim 1, characterized in that, Based on the material of the cable, cables with metal as the core material are classified as metal cables, while cables with natural or synthetic fibers or composite materials as the core material are classified as non-metallic cables.

3. The method for testing cable strength according to claim 1, characterized in that, The method for determining the equipment selection for a phased array system is as follows: The metal cable is acquired and pre-treated, including cleaning, straightening, and marking. Cleaning involves blowing away surface dust with high-pressure air and wiping away oil and rust with alcohol or a special cleaning agent. Straightening involves slightly straightening the cable with a special fixture to ensure the surface of the detection area is flat. Marking involves dividing the detection unit according to the length and circumference of the cable. A high-frequency arc array probe is selected as the phased array probe, and a dual-crystal angle probe is selected as the TOFD probe. An oil-based high-viscosity coupling agent is also used.

4. The cable strength testing method according to claim 1, characterized in that, The method for scanning defective areas of metal cables is as follows: For spiral scanning, the probe is moved along the length of the cable while slowly rotating around the circumference of the cable to achieve full coverage scanning of the entire cable and generate a planar view. For circumferential fixed-point scanning, abnormal areas with abrupt changes in reflected waves are obtained in the planar view. Then, the probe is continuously scanned around the circumference to generate a cross-sectional view. At the same time, the image appearance of the area corresponding to the abnormal area in the cross-sectional view is identified. If a certain area shows continuous strong reflected waves and the amplitude exceeds the amplitude of the standard defect in the calibration block, it is judged to be a defect area.

5. The cable strength testing method according to claim 1, characterized in that, The method for generating metal cable detection information is as follows: Draw a line through the center of the probe across the abnormal area, and then obtain the incident angle of the probe wedge. The longitudinal wave velocity c1 of the wedge and the longitudinal wave velocity c2 of the metal cable are determined according to the formula... =(c1 / c2)× Calculated Furthermore, it was deduced that the angle of refraction... ; The ultrasonic A-scan signal of the defect region is extracted, and the A-scan signal represents the amplitude-time curve of a single detection point, which is the raw data. The S-wave diffraction wave at the upper end of the defect and the P-wave diffraction wave at the lower end are identified, and the time difference between the two is calculated and denoted as . According to the formula, defect depth = (c² × ... ) / (2×cos The defect depth is calculated. The obtained defect depth is compared with the corresponding first standard allowable value, which is set by the operator. If the defect depth is less than or equal to the first standard allowable value, it is considered qualified. Conversely, if the defect depth is greater than the first standard allowable value, it is considered unqualified and the corresponding metal cable inspection information is generated simultaneously.

6. The method for testing cable strength according to claim 1, characterized in that, The specific method for setting up the detection system is as follows: The laser ultrasound module emits a laser at a 45° incident angle to irradiate the cable surface. The receiving interferometer is positioned directly above the cable surface. The ultrasonic microscope module aligns the microscope probe with the cable scanning area, maintaining a distance of 0.5-1 mm or close to the water film between the probe and the cable surface. The motion control platform uses an XYZ three-axis electric platform to drive the cable or probe to perform line scanning and surface scanning. Line scanning is performed along the length of the cable, while surface scanning covers the circumference of the cable. The scan is performed once every 10° of rotation to ensure no blind spots.

7. The method for testing cable strength according to claim 1, characterized in that, The method for identifying suspected defect areas is as follows: The laser ultrasonic module emits pulsed lasers to generate a thermoelastic effect on the surface of the cable and excite longitudinal and transverse ultrasonic signals. At the same time, the laser interferometer receives and identifies the two types of key signals, performs line scanning along the length of the cable, collects one set of signals every 10 mm, records the position of the defect reflection wave, and marks the corresponding area as a suspected defect area. The suspected defect area is acquired, and a rapid coarse scan is performed with low resolution and a large scanning range to obtain a planar top view and a cross-sectional side view. Then, the lateral boundary of the suspected defect is determined by the planar top view, and the depth distribution of the defect is preliminarily determined by the cross-sectional side view. The core area of ​​the suspected defect area is marked.

8. The cable strength testing method according to claim 1, characterized in that, The method for classifying defect types is as follows: Extract the signal features corresponding to the amplitude-time curve of a single detection point. If the signal features have two consecutive reflected waves with medium amplitude, they are classified as microcracks. If the signal features have one strong reflected wave with high amplitude, they are classified as micro-inclusions. If the signal features have one strong reflected wave with no subsequent signal, they are classified as micro-voids.

9. The method for testing cable strength according to claim 1, characterized in that, The method for generating non-metallic cable detection information is as follows: Obtain the acoustic path difference between the upper and lower endpoints of the defect and the sample surface in the cross-sectional side view. , specific Given the time difference between the reflected waves at the upper and lower ends of the defect, the longitudinal wave velocity c3 of the non-metallic cable is obtained. According to the formula: Defect Depth = (c3 × ... The corresponding defect depth is calculated by dividing the result by 2. The obtained defect depth is compared with the corresponding second standard allowable value, and the specific value of the second standard allowable value is set by the operator. If the defect depth is less than or equal to the second standard allowable value, it is judged as qualified. Conversely, if the defect depth is greater than the second standard allowable value, it indicates that it exceeds the standard and is judged as unqualified. At the same time, the corresponding non-metallic cable inspection information is generated.

10. A cable strength testing system for performing the cable strength testing method according to any one of claims 1-9, characterized in that, include: The cable information acquisition module is used to acquire the cable to be tested, determine the cable material of the cable to be tested, and classify it into metal cable and non-metal cable according to the cable material, and transmit the information of the two separately. The metal cable inspection and analysis module is used to clean, straighten, and mark the metal cable sequentially, and to determine the equipment selection for the phased array system. It uses a combination of spiral scanning and circumferential fixed-point scanning to scan the defect area of ​​the metal cable. For the identified defect area, ultrasonic mode analysis is used to extract the amplitude-time curve of a single detection point in the defect area and calculate the defect depth. At the same time, it is compared with the first standard allowable value to generate metal cable inspection information and transmit it to the inspection information output module. The non-metallic cable inspection and analysis module is used to perform surface cleaning and leveling of non-metallic cables. It is equipped with an inspection system including a laser ultrasonic module, an ultrasonic microscope module, and a motion control platform. The laser ultrasonic module emits pulsed lasers, receives defect reflection wave signals from the interferometer, and identifies suspected defect areas. Based on the characteristics corresponding to the amplitude-time curve of a single detection point in the core area, the defect type is classified and the defect depth is calculated. At the same time, it is compared with the second standard allowable value to generate non-metallic cable inspection information and transmit it to the inspection information output module. The detection information output module is used to display the acquired detection information of metal cables and non-metal cables to the corresponding management personnel.

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