Steel wire rope defect detection method and device based on variable magnetic field array

Abstract

A wire rope defect detection method and device based on a variable magnetic field array, comprising: setting at least two markers on the detected wire rope; deploying a variable magnetic field array; making a first adjustment to generate a first magnetic field; using the first magnetic field to magnetize the wire rope for the first time; performing a first detection on the wire rope to obtain a first defect feature; fine-tuning at least one characteristic parameter of all variable magnets for multiple times to generate a transition magnetic field; using the transition magnetic field to fine-tune the magnetic field of the wire rope to be detected; making a second adjustment to all variable magnets to generate a second magnetic field; using the second magnetic field to magnetize the wire rope for the second time; performing a second detection on the wire rope to obtain a second defect feature; and fusing the first defect feature and the second defect feature based on the position of the marker. The present invention can form a flexibly adjustable magnetic field to detect the wire rope under different magnetic fields, and the detection results can be mutually verified to ensure the accuracy of the detection results.

Description

Technical Field

[0001] The invention relates to the technical field of wire rope flaw detection, in particular to a wire rope defect detection method and device based on a variable magnetic field array. Background Art

[0002] As an important component widely used in lifting equipment, steel wire rope has the advantages of light weight, high tensile strength, strong bearing capacity, good flexibility, etc., and is therefore widely used in many fields. Due to the serious instability of its service environment, steel wire ropes will have defects such as broken wires, wear and corrosion during service, which may damage their own performance and cause serious safety accidents. Therefore, in order to reduce the occurrence of safety accidents and protect people's lives and property, it is very important to use appropriate non-destructive testing methods to conduct safety testing and evaluation of steel wire ropes.

[0003] In the prior art, the main non-destructive testing method for wire ropes is the magnetic flux leakage testing method. The main steps of the magnetic flux leakage testing method are to first generate a magnetic field, use the magnetic field to magnetize the wire rope, and then detect the magnetic flux leakage of the magnetized wire rope to determine whether the wire rope has defects and the type of defects. The magnetic flux leakage testing method has the advantages of simple operation and intuitive display results. However, the detection basis of the magnetic flux leakage testing method is single, and the defects of the wire rope are judged only by the result of one magnetization. In practical application, there is a problem of limited accuracy of the detection results. Summary of the invention

[0004] In order to address the deficiencies in the prior art, the present invention provides a wire rope defect detection method and device based on a variable magnetic field array. The variable magnetic field array can form a flexibly adjustable magnetic field, and then the detected wire rope is tested under a variety of magnetic fields. The final actual defect data is obtained by fusing different test results. The various test results can be verified with each other to jointly ensure the accuracy of the actual defect data.

[0005] In order to achieve the above object, the specific scheme adopted by the present invention is: a wire rope defect detection method based on a variable magnetic field array, comprising the following steps:

[0006] At least two markers are set on the steel wire rope to be tested, and a distance is left between the two markers;

[0007] Deploy a variable magnetic field array, the variable magnetic field array is generated by a plurality of variable magnets distributed in a ring shape, and the plurality of variable magnets enclose a detection space for the detected wire rope to pass through, and the variable magnets have a plurality of characteristic parameters, including magnetic field direction and magnetic field strength;

[0008] Performing a first adjustment on at least one characteristic parameter of all variable magnets to generate a first magnetic field;

[0009] The steel wire rope to be tested is passed through a first magnetic field, and the steel wire rope is magnetized for the first time by using the first magnetic field;

[0010] Conduct a first inspection on the wire rope to obtain the first defect feature;

[0011] Fine-tuning at least one characteristic parameter of all variable magnets for multiple times to generate a transition magnetic field, wherein the fine-tuned characteristic parameter is the same as the first adjusted characteristic parameter;

[0012] Make the steel wire rope to be tested pass through the transition magnetic field, and use the transition magnetic field to fine-tune the magnetic field of the steel wire rope to be tested;

[0013] Performing a second adjustment on all variable magnets to generate a second magnetic field, wherein the characteristic parameters of the second adjustment are the same as the characteristic parameters of the first adjustment;

[0014] The steel wire rope to be tested is passed through a second magnetic field, and the steel wire rope is magnetized for a second time by using the second magnetic field;

[0015] Conduct a second inspection on the wire rope to obtain a second defect feature;

[0016] The first defect feature and the second defect feature are fused based on the position of the marker to obtain actual defect data.

[0017] As a further optimization of the above-mentioned wire rope defect detection method based on a variable magnetic field array: the specific method of setting at least two markers on the detected wire rope includes:

[0018] The steel wire rope to be tested is divided into multiple sections, and the total length of all the sections is equal to the length of the steel wire rope to be tested;

[0019] Dividing the segment into a parallel detection area and a marking area;

[0020] Markers are set correspondingly on the marked area, and any two markers are different;

[0021] When the first defect feature and the second defect feature are fused based on the position of the marker to obtain the actual defect, the first defect feature and the second defect feature are located based on the position of the marker and then fused.

[0022] As a further optimization of the above-mentioned wire rope defect detection method based on a variable magnetic field array: a method for locating the first defect feature and the second defect feature based on the position of the marker includes:

[0023] Outputting the result of the first detection and the result of the second detection as time domain waveforms;

[0024] Extracting a marker band corresponding to the marker, a first defect band corresponding to the first defect feature, and a second defect band corresponding to the second defect feature from the time domain waveform;

[0025] Calculate the duration between any two adjacent marked bands, first defect bands or second defect bands;

[0026] Calculate the spatial distance between any two adjacent marking bands, the first defect band or the second defect band based on the duration and the moving speed of the detected wire rope;

[0027] The defect positions of the first defect feature and the second defect feature on the inspected steel wire rope are determined based on the position and spatial distance of the marking area on the inspected steel wire rope.

[0028] As a further optimization of the above-mentioned wire rope defect detection method based on a variable magnetic field array: a method for fusing the first defect feature and the second defect feature is:

[0029] Calculating the overlap between the first defect band and the second defect band;

[0030] When the overlap between the first defect band and the second defect band reaches a preset overlap threshold, the first defect feature and the second defect feature are merged into a real defect feature;

[0031] All real defect features are integrated into actual defect data.

[0032] As a further optimization of the above-mentioned wire rope defect detection method based on variable magnetic field array: the characteristic parameters of the first adjustment, fine-tuning and second adjustment are all magnetic field directions, the magnetic field direction of the first magnetic field in the detection space is parallel to the length direction of the detected wire rope, and the magnetic field direction of the second magnetic field in the detection space is perpendicular to the length direction of the wire rope.

[0033] As a further optimization of the above-mentioned wire rope defect detection method based on a variable magnetic field array: the angle between the magnetic field direction of the transition magnetic field in the detection space and the magnetic field direction of the first magnetic field in the detection space, the angle between the magnetic field directions of two adjacent transition magnetic fields in the detection space, and the angle between the magnetic field direction of the transition magnetic field in the detection space and the magnetic field direction of the second magnetic field in the detection space are all less than or equal to a preset deflection angle threshold.

[0034] A steel wire rope defect detection device based on a variable magnetic field array is used to implement the above-mentioned steel wire rope defect detection method based on a variable magnetic field array, and the device comprises:

[0035] A plurality of variable magnets distributed in a ring shape, the plurality of variable magnets are used to generate the variable magnetic field array, and the plurality of variable magnets enclose the detection space for the steel wire rope to pass through;

[0036] A plurality of adjusting mechanisms, each of which corresponds to the variable magnet, are used to adjust the magnetic field direction and spatial position of the variable magnet.

[0037] As a further optimization of the above-mentioned wire rope defect detection device based on a variable magnetic field array: the adjustment mechanism includes two parallel connecting plates and a rotating ring rotatably connected to the two connecting plates, a driving wheel is rotatably arranged between the two connecting plates, the driving wheel is connected to a driving motor for driving the driving wheel to rotate, a second accommodating groove is provided on the circumferential side wall of the driving wheel, the variable magnet is fixed on the inner side of the rotating ring, and a first accommodating groove extending in a circumferential direction is provided on the outer circumferential side wall of the rotating ring, the driving wheel drives the rotating ring to rotate through a transmission belt, and the transmission belt is located in the first accommodating groove and the second accommodating groove.

[0038] As a further optimization of the above-mentioned wire rope defect detection device based on a variable magnetic field array: a rolling groove extending in a circumferential direction is respectively opened on the two end walls of the rotating ring, and the connecting plate is fixedly connected with at least one plug rod, the plug rod is inserted into the rolling groove, and a rotating sleeve is provided on the plug rod, and the rotating sleeve is in contact with the inner wall of the rolling groove.

[0039] As a further optimization of the above-mentioned wire rope defect detection device based on a variable magnetic field array: the adjustment mechanism also includes a linear drive, a connecting block is fixedly connected between the two connecting plates, the connecting block is fixedly connected to the output end of the linear drive, and the linear drive drives the variable magnet to approach or move away from the detection space during operation.

[0040] Beneficial effects: The present invention can form a flexibly adjustable magnetic field through a variable magnetic field array, and then perform detection on the detected wire rope under multiple magnetic fields, and obtain the final actual defect data by fusing different detection results. The various detection results can be verified with each other to jointly ensure the accuracy of the actual defect data; the present invention also sets markers on the wire rope, and uses the position of the markers to verify and fuse different detection results, which fully ensures the accuracy of the actual defect data and can also accurately locate the defects. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is a flow chart of the detection method of the present invention;

[0042] Figure 2 is a schematic diagram of the distribution of variable magnets;

[0043] Figure 3 It is a schematic diagram of the installation method of the variable magnet in the detection device of the present invention;

[0044] Figure 4It is a schematic diagram of the connection method between the rotating ring and the connecting plate in the detection device of the present invention.

[0045] Description of the drawings: 1-variable magnet, 2-detection space, 3-wire rope, 4-rotating ring, 5-first accommodating groove, 6-transmission belt, 7-mounting block, 8-connecting plate, 9-driving wheel, 10-second accommodating groove, 11-driving motor, 12-connecting block, 13-linear drive, 14-rolling groove, 15-insertion rod, 16-rotating sleeve, 17-grease. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 creative work are within the scope of protection of the present invention.

[0047] See also Figure 1 and 2 The present invention first provides a wire rope defect detection method based on a variable magnetic field array, including S1 to S11.

[0048] S1. Setting at least two markers on the steel wire rope to be detected, and leaving a distance between the two markers. The specific method of setting at least two markers on the steel wire rope to be detected includes S101 to S103.

[0049] S101, divide the detected wire rope into multiple sections, and the total length of all sections is equal to the length of the detected wire rope. According to actual needs, the length of the section can be set to an appropriate value, and the lengths of two sections can be equal or unequal. It only needs to ensure that the total length of all sections is equal to the length of the detected wire rope, that is, to ensure that any position on the wire rope belongs to one of the sections.

[0050] S102, dividing the segment into parallel detection areas and marking areas.

[0051] S103. Set markers corresponding to the marking area, and any two markers are different. The marker is used to mark the steel wire rope being tested. The marker will generate a special magnetic field after being magnetized. When the magnetic field state of the steel wire rope is detected to determine the defects of the steel wire rope, the position of the defect can be determined based on the position of the marker, so as to more accurately grasp the state of the steel wire rope. Different markers use different structures, and the marker can be identified by the special state of the marker after being magnetized, ensuring that the position of the defect can be determined more accurately using the marker. The marker can be made of ferromagnetic material or a material doped with metal particles of organic matter.

[0052] It should be noted that, for wire ropes that remain stationary during use, such as wire ropes used to suspend objects, markers can be directly mounted on the wire ropes; for wire ropes that have been removed from their working positions, markers can also be directly mounted on the wire ropes; for wire ropes that need to remain in motion during use, such as wire ropes for traction elevators, markers need to avoid the side where the wire rope contacts the sheave, to ensure that the markers do not contact the sheave during movement and be worn or fall off.

[0053] S2. Deploy a variable magnetic field array, which is generated by multiple variable magnets distributed in a ring shape, and the multiple variable magnets enclose a detection space for the detected wire rope to pass through. The variable magnets have multiple characteristic parameters, including magnetic field direction and magnetic field strength. By adjusting the characteristic parameters of the variable magnets, a variety of different magnetic fields can be formed in the detection space, and then the detected wire rope is magnetized in different ways. The defects of the wire rope are detected under different magnetization methods, which can improve the accuracy of the detection results.

[0054] S3, adjusting at least one characteristic parameter of all variable magnets for the first time to generate a first magnetic field. The characteristic parameter adjusted for the first time is the magnetic field direction, and the magnetic field direction of the first magnetic field in the detection space is the axial direction of the detection space.

[0055] S4. Make the steel wire rope to be tested pass through the first magnetic field, and use the first magnetic field to magnetize the steel wire rope for the first time.

[0056] S5. Perform a first inspection on the steel wire rope to obtain a first defect characteristic. After the steel wire rope is magnetized for the first time, perform a first inspection on the steel wire rope to obtain a first defect characteristic exhibited by the defect position of the steel wire rope after the first magnetization.

[0057] S6. Fine-tune at least one characteristic parameter of all variable magnets for multiple times to generate a transition magnetic field. The fine-tuned characteristic parameter is the same as the characteristic parameter adjusted for the first time, that is, the fine-tuned characteristic parameter is also the magnetic field direction. By fine-tuning the magnetic field direction of the variable magnet, the magnetic field direction of the magnetic field in the detection space can be changed successively.

[0058] S7, the steel wire rope to be tested is passed through the transition magnetic field, and the magnetic field of the steel wire rope to be tested is fine-tuned by using the transition magnetic field. After each fine-tuning, the steel wire rope to be tested is passed through the transition magnetic field, and the magnetization state of the steel wire rope can be gradually changed.

[0059] S8. A second adjustment is performed on all variable magnets to generate a second magnetic field. The characteristic parameters of the second adjustment are the same as those of the first adjustment, that is, the characteristic parameters of the second adjustment are also the magnetic field direction. After multiple fine-tuning and the second adjustment, the magnetic field direction of the second magnetic field in the detection space is greatly different from the magnetic field direction of the first magnetic field in the detection space, thereby being able to completely change the magnetization state of the wire rope.

[0060] S9, allowing the steel wire rope to be tested to pass through a second magnetic field, and utilizing the second magnetic field to magnetize the steel wire rope for a second time.

[0061] S10, performing a second inspection on the steel wire rope to obtain a second defect characteristic.

[0062] S11. Based on the position of the marker, the first defect feature and the second defect feature are merged to obtain actual defect data.

[0063] In one embodiment of the present invention, the characteristic parameters of the first adjustment, fine adjustment and second adjustment are all magnetic field directions, the magnetic field direction of the part of the first magnetic field in the detection space is parallel to the length direction of the detected wire rope, and the magnetic field direction of the part of the second magnetic field in the detection space is perpendicular to the length direction of the wire rope. After the variable magnet is adjusted for the first time to generate the first magnetic field, the wire rope is made to pass through the detection space at a uniform speed along the axis of the detection space. During the process, the wire rope is magnetized for the first time. After the first magnetization, the spontaneous magnetization direction of the magnetic domain inside the detected wire rope is the axis direction of the detection space, which is also the length direction of the wire rope. After that, the wire rope is tested for the first time, and the first defect feature shown by the defect position of the wire rope after the first magnetization can be obtained. Subsequently, multiple transition magnetic fields are generated by multiple fine adjustments, and the magnetic field direction of the magnetic field in the detection space can be continuously adjusted. After each fine adjustment, the detected wire rope is made to pass through the detection space at a uniform speed, which can gradually change the magnetization state of the wire rope and the spontaneous magnetization direction of the magnetic domain inside the wire rope. Finally, after the variable magnet is adjusted for the second time to generate the second magnetic field, the steel wire rope is made to pass through the detection space again at a uniform speed along the axis of the detection space. During the process, the steel wire rope is magnetized for the second time. After the second magnetization, the spontaneous magnetization direction of the magnetic domain inside the detected steel wire rope is perpendicular to the length direction of the steel wire rope, that is, the spontaneous magnetization direction of the magnetic domain inside the detected steel wire rope after the second magnetization is the radial direction of the steel wire rope. After that, the steel wire rope is tested for the second time, and the second defect feature manifested by the defect position of the steel wire rope after the second magnetization can be obtained. On the other hand, the marker will be magnetized in the first magnetic field, the transition magnetic field and the second magnetic field, and because the marker is fixed on the detected steel wire rope and the structure of the marker is different from that of the steel wire rope, the marker can generate a magnetic field different from both the steel wire rope and the defect after being magnetized, and the marker can also be determined according to the magnetic field generated by the marker during the first and second detection processes.

[0064] After obtaining the first defect feature and the second defect feature, the positions of the first defect and the second defect reflected by the first defect feature and the second defect feature are determined based on the position of the marker. If the position of the first defect and the position of the second defect are consistent, it means that the wire rope shows the same defect after the first magnetization and the second magnetization, and it can be determined that the defect objectively exists, thereby effectively ensuring the accuracy of the detection result.

[0065] More specifically, when the first defect feature and the second defect feature are merged based on the position of the marker to obtain the actual defect, the first defect feature and the second defect feature are located based on the position of the marker and then merged. The method of locating the first defect feature and the second defect feature based on the position of the marker includes S111 to S115.

[0066] S111, output the results of the first test and the second test as time domain waveforms. Because the tested wire rope moves at a constant speed in the test space, the moving distance of the wire rope can be calculated in combination with the time, and then the position of the defect on the wire rope can be determined.

[0067] S112, extracting the marker band corresponding to the marker, the first defect band corresponding to the first defect feature, and the second defect band corresponding to the second defect feature from the time domain waveform. As described above, the magnetic field generated by the magnetized marker, the magnetic field generated by the magnetized wire rope, and the magnetic field generated by the magnetized defect are all different, so the positions of the marker band, the first defect band, and the second defect band can be easily determined from the time domain waveform.

[0068] S113: Calculate the duration between any two adjacent mark bands, first defect bands or second defect bands.

[0069] S114, calculate the spatial distance between any two adjacent marking bands, the first defect band or the second defect band based on the time length and the moving speed of the detected wire rope. Because the wire rope moves at a uniform speed, the distance between any two adjacent markers, the first defect or the second defect can be obtained according to the product of the time length between the marking band, the first defect band and the second time band and the speed of the wire rope. Because the position of the marker on the wire rope is fixed, the first defect and the second defect can be accurately located based on the position of the marker and the calculated distance.

[0070] S115, determine the defect positions of the first defect feature and the second defect feature on the detected wire rope based on the position and spatial distance of the marked area on the detected wire rope. More specifically, the method for fusing the first defect feature and the second defect feature is S1151 to S1153.

[0071] S1151. Calculate the overlap between the first defect band and the second defect band. The overlap here refers to the overlap between the time segment corresponding to the first defect band and the time segment corresponding to the second defect band in the time domain waveform. If the start time and the end time of the first defect band and the second defect band are consistent, the overlap is complete overlap.

[0072] S1152: When the overlap between the first defect band and the second defect band reaches a preset overlap threshold, the first defect feature and the second defect feature are merged into a real defect feature.

[0073] S1153. Integrate all real defect features into actual defect data.

[0074] If the overlap between the first defect band and the second defect band reaches the preset overlap threshold, it means that the positions of the first defect and the second defect on the wire rope are highly overlapped, which means that in both the first and second tests, it is determined that there is a defect at a certain position on the wire rope, and the results of the two tests can verify each other, thereby fully ensuring the accuracy of the test results. Finally, all real defect features are integrated into actual defect data, and the actual defect data is analyzed to determine the type of detected defects. Different types of defects generate different magnetic fields after being magnetized. The method of analyzing the actual defect data to obtain the defect type belongs to the conventional technical means in this field and will not be repeated here.

[0075] Because the magnetic field direction of the first magnetic field in the detection space and the magnetic field direction of the second magnetic field in the detection space are perpendicular to each other, if the second magnetic field is directly generated by the variable magnetic field array, it will be difficult to change the spontaneous magnetization direction of the magnetic domain in the wire rope, because the force of the second magnetic field on the magnetic domain and the original spontaneous magnetization direction of the magnetic domain caused by the influence of the first magnetic field are perpendicular to each other, so it is necessary to continuously adjust the spontaneous magnetization direction of the magnetic domain through the transition magnetic field. Further, the angle between the magnetic field direction of the transition magnetic field in the detection space and the magnetic field direction of the first magnetic field in the detection space, the angle between the magnetic field directions of two adjacent transition magnetic fields in the detection space, and the angle between the magnetic field direction of the transition magnetic field in the detection space and the magnetic field direction of the second magnetic field in the detection space are all less than or equal to the preset deflection angle threshold. The spontaneous magnetization direction of the magnetic domain in the wire rope is gradually rotated by the transition magnetic field until it is perpendicular to the length direction of the wire rope, which can ensure that the spontaneous magnetization direction of the magnetic domain in the wire rope can be adjusted from a direction parallel to the axis of the wire rope to a direction perpendicular to the axis of the wire rope.

[0076] In other embodiments of the present invention, the results of the first detection and the results of the second detection can also be output as a spatial waveform, that is, the position on the wire rope is output as the horizontal coordinate and the magnetic field characteristics are output as the vertical coordinate. Because the length of the detected wire rope is determined, the position of one of the markers on the wire rope can be set as the starting point of the horizontal coordinate, and the part of the results of the first detection and the results of the second detection corresponding to the marker at the starting point can be adjusted to the starting point of the horizontal coordinate to achieve normalization of the spatial waveform. When the results of the first detection and the results of the second detection are both output as spatial waveforms, the positions of the first defect band and the second defect band are directly determined based on the horizontal coordinate, and then combined with the position of the starting point, the positions of the first defect and the second defect can be determined.

[0077] When the results of the first test and the second test are output as time domain waveforms, there is no need to normalize the starting point of the waveform, and the waveform output process is simpler. However, when determining the positions of the first defect and the second defect in the future, it is necessary to combine the time and the moving speed of the wire rope to determine the distance between the first defect and the second defect to determine the positions of the first defect and the second defect; when the results of the first test and the second test are output as air domain waveforms, the positions of the first defect and the second defect can be directly determined in the future, but the air domain waveforms need to be normalized first, that is, to ensure that the two air domain waveforms have the same starting point. In practical applications, the appropriate waveform can be flexibly selected.

[0078] In other embodiments of the detection method of the present invention, the characteristic parameters to be adjusted may be the magnetic field intensity and the variable magnet spatial position in addition to the magnetic field direction, or any combination of the magnetic field direction, magnetic field intensity and the variable magnet spatial position. Regardless of the adjustment method, it is necessary to ensure that the first magnetic field and the second magnetic field are different, so as to detect the steel wire rope by using different magnetic fields, and then the results of the two tests can be mutually verified, fully ensuring the accuracy of the final test result.

[0079] Finally, because setting a marker on the inspected wire rope will partially block the wire rope, the marker may just block the defect, which will cause some defects on the wire rope to be undetectable. To avoid this, after the first and second inspections, all markers can be moved synchronously, so that all markers move the same distance in the same direction, open the originally blocked marking area, and then perform two more inspections to detect whether there are defects in the original marking area.

[0080] See also Figures 2 to 4 The present invention further provides a steel wire rope defect detection device based on a variable magnetic field array, which is used to implement the above-mentioned steel wire rope defect detection method based on a variable magnetic field array. The device includes a plurality of variable magnets 1 distributed in a ring shape and a plurality of adjustment mechanisms.

[0081] A plurality of variable magnets 1 are distributed in a ring shape, and the plurality of variable magnets 1 are used to generate a variable magnetic field array, and the plurality of variable magnets 1 enclose a detection space 2 for the steel wire rope 3 to pass through.

[0082] Multiple adjustment mechanisms, each adjustment mechanism corresponds to the variable magnet 1 one by one, and the adjustment mechanism is used to adjust the magnetic field direction and spatial position of the variable magnet 1. More specifically, the adjustment mechanism can adjust the magnetic field direction of the variable magnet 1 by rotating the variable magnet 1, and can make the variable magnet 1 approach or move away from the detection space by pushing and pulling the variable magnet 1, thereby changing the spatial position of the variable magnet 1.

[0083] The specific structure of the adjustment mechanism is as follows: the adjustment mechanism includes two parallel connection plates 8 and a rotating ring 4 that is rotatably connected to the two connection plates 8. A driving wheel 9 is rotatably arranged between the two connection plates 8. The driving wheel 9 is connected to a driving motor 11 for driving the driving wheel 9 to rotate. A second receiving groove 10 is provided on the peripheral side wall of the driving wheel 9. The variable magnet 1 is fixed on the inner side of the rotating ring 4, and both ends of the variable magnet 1 are fixedly connected to the rotating ring 4 through a mounting block 7. A first receiving groove 5 extending along the circumferential direction is provided on the outer peripheral side wall of the rotating ring 4. The driving wheel 9 drives the rotating ring 4 to rotate through a transmission belt 6, and the transmission belt 6 is located in the first receiving groove 5 and the second receiving groove 10. When it is necessary to use the adjustment mechanism to drive the variable magnet 1 to rotate to change the magnetic field direction of the variable magnet 1, the driving motor 11 is used to drive the driving wheel 9 to rotate. During the rotation of the driving wheel 9, the rotating ring 4 is driven to rotate through the transmission belt 6, and then the inner variable magnet 1 is driven to rotate through the rotating ring 4, so as to achieve the effect of changing the angle and magnetic field direction of the variable magnet 1. Furthermore, because the rotating ring 4 and the two connecting plates 8 are rotatably connected, there is no need to provide an additional supporting structure for the rotating ring 4, which can make the structure of the adjustment mechanism simpler.

[0084] Furthermore, the specific connection method between the rotating ring 4 and the connecting plate 8 is as follows: a rolling groove 14 extending in the circumferential direction is respectively provided on the two end walls of the rotating ring 4, and at least one plug rod 15 is fixedly connected to the connecting plate 8, the plug rod 15 is inserted into the rolling groove 14, and a rotating sleeve 16 is rotatably provided on the plug rod 15, and the rotating sleeve 16 contacts the inner wall of the rolling groove 14. During the rotation of the rotating ring 4, the plug rod 15 can slide in the rolling groove 14, thereby ensuring that the rotating ring 4 can rotate smoothly. The provision of the rotating sleeve 16 can avoid sliding friction between the plug rod 15 and the inner wall of the rolling groove 14, can avoid rapid wear of the plug rod 15, and ensure the service life of the adjustment mechanism. A lubrication groove can also be provided on the inner wall of the rotating sleeve 16, and grease 17 can be filled in the lubrication groove. During the rotation of the rotating sleeve 16, the grease 17 can lubricate the contact surface between the rotating sleeve 16 and the plug rod 15, thereby avoiding wear of the rotating sleeve 16 or the plug rod 15. An excess amount of grease 17 may also be added so that the grease 17 can overflow from the lubrication groove and lubricate the contact surface between the rotating sleeve 16 and the rolling groove 14. During the assembly process, the insertion rod 15 may be first inserted into the rolling groove 14, and then the connecting plate 8 may be moved to the side of the rotating ring 4, and then the connecting plate 8 may be connected to the insertion rod 15 by bolting or welding.

[0085] The above structure of the adjustment mechanism can achieve the effect of rotating the variable magnet 1 to change the angle and magnetic field direction of the variable magnet 1. In order to achieve the effect of adjusting the spatial position of the variable magnet 1, the adjustment mechanism also includes a linear driver 13. A connecting block 12 is fixedly connected between the two connecting plates 8. The connecting block 12 is fixedly connected to the output end of the linear driver 13. During the operation of the linear driver 13, the variable magnet 1 is driven to approach or move away from the detection space 2. The linear driver 13 can adopt conventional devices with linear output capabilities such as cylinders or electric push rods, which can be flexibly selected according to actual needs, and will not be repeated here. It should also be noted that after the magnetic field direction of the variable magnet 1 is determined, changing the spatial position of the variable magnet 1 will not affect the magnetic field direction of the variable magnet 1, but will affect the magnetic field strength of the magnetic field generated by the variable magnet 1 in the detection space. Therefore, by changing the spatial position of the variable magnet 1, it can be coordinated with changing the current of the variable magnet 1. The two methods jointly change the magnetic field strength in the detection space, so that the adjustable range of the magnetic field strength in the detection space is larger and more flexible and easy to use.

[0086] In the present invention, the variable magnet 1 can be an electromagnet or a permanent magnet. When an electromagnet is used, the magnetic field strength of the generated magnetic field is changed by changing the current in the electromagnet. When a permanent magnet is used, the distance between the permanent magnet and the detection space 2 is changed by an adjustment mechanism to change the magnetic field strength it generates.

[0087] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A wire rope defect detection method based on a variable magnetic field array, characterized in that: The steps include: At least two markers are set on the steel wire rope to be tested, and a distance is left between the two markers; The specific method of setting at least two markers on the detected wire rope includes: The steel wire rope to be tested is divided into multiple sections, and the total length of all sections is equal to the length of the steel wire rope to be tested; Dividing the segment into a parallel detection area and a marking area; Markers are set correspondingly on the marked area, and any two markers are different; When the first defect feature and the second defect feature are fused based on the position of the marker to obtain the actual defect, the first defect feature and the second defect feature are located and fused based on the position of the marker; Deploy a variable magnetic field array, the variable magnetic field array is generated by a plurality of variable magnets distributed in a ring shape, and the plurality of variable magnets enclose a detection space for the detected wire rope to pass through, and the variable magnets have a plurality of characteristic parameters, including magnetic field direction and magnetic field strength; Performing a first adjustment on at least one characteristic parameter of all variable magnets to generate a first magnetic field, wherein the adjusted characteristic parameter includes a magnetic field direction; The steel wire rope to be tested is passed through a first magnetic field, and the steel wire rope is magnetized for the first time by using the first magnetic field; Conduct a first inspection on the wire rope to obtain the first defect feature; Fine-tuning at least one characteristic parameter of all variable magnets for multiple times to generate a transition magnetic field, wherein the fine-tuned characteristic parameter is the same as the first adjusted characteristic parameter; Make the steel wire rope to be tested pass through the transition magnetic field, and use the transition magnetic field to fine-tune the magnetic field of the steel wire rope to be tested; Performing a second adjustment on all variable magnets to generate a second magnetic field, wherein the characteristic parameters of the second adjustment are the same as the characteristic parameters of the first adjustment; The steel wire rope to be tested is passed through a second magnetic field, and the steel wire rope is magnetized for a second time by using the second magnetic field; Conduct a second inspection on the wire rope to obtain a second defect feature; The first defect feature and the second defect feature are merged based on the position of the marker to obtain actual defect data; the method for locating the first defect feature and the second defect feature based on the position of the marker includes: Outputting the result of the first detection and the result of the second detection as time domain waveforms; Extracting a marker band corresponding to the marker, a first defect band corresponding to the first defect feature, and a second defect band corresponding to the second defect feature from the time domain waveform; Calculate the duration between any two adjacent marked bands, first defect bands or second defect bands; Calculate the spatial distance between any two adjacent marking bands, the first defect band or the second defect band based on the duration and the moving speed of the detected wire rope; Determine the defect positions of the first defect feature and the second defect feature on the inspected steel wire rope based on the position and spatial distance of the marking area on the inspected steel wire rope; After the first and second inspections, all markers are moved synchronously so that all markers move the same distance in the same direction to open the originally blocked marking area, and then two inspections are performed again to detect whether there are defects in the original marking area.

2. The method for detecting defects in steel wire ropes based on a variable magnetic field array according to claim 1, characterized in that: The method for fusing the first defect feature and the second defect feature is: Calculating the overlap between the first defect band and the second defect band; When the overlap between the first defect band and the second defect band reaches a preset overlap threshold, the first defect feature and the second defect feature are merged into a real defect feature; All real defect features are integrated into actual defect data.

3. The method for detecting defects in steel wire ropes based on a variable magnetic field array according to claim 1, characterized in that: The characteristic parameters of the first adjustment, fine-tuning and second adjustment are all magnetic field directions. The magnetic field direction of the first magnetic field in the detection space is parallel to the length direction of the detected wire rope, and the magnetic field direction of the second magnetic field in the detection space is perpendicular to the length direction of the wire rope.

4. The method for detecting defects in steel wire ropes based on a variable magnetic field array according to claim 3, characterized in that: The angle between the magnetic field direction of the transition magnetic field in the detection space and the magnetic field direction of the first magnetic field in the detection space, the angle between the magnetic field directions of two adjacent transition magnetic fields in the detection space, and the angle between the magnetic field direction of the transition magnetic field in the detection space and the magnetic field direction of the second magnetic field in the detection space are all less than or equal to a preset deflection angle threshold.

5. A wire rope defect detection device based on a variable magnetic field array, characterized in that: The device is used to implement the wire rope defect detection method based on a variable magnetic field array as described in any one of claims 1 to 4, the device comprising: A plurality of variable magnets (1) distributed in a ring shape, the plurality of variable magnets (1) being used to generate the variable magnetic field array, and the plurality of variable magnets (1) enclosing the detection space (2) for the steel wire rope (3) to pass through; A plurality of adjustment mechanisms, each adjustment mechanism corresponding to the variable magnet (1) one by one, the adjustment mechanism being used to adjust the magnetic field direction and spatial position of the variable magnet (1); The adjustment mechanism comprises two parallel connection plates (8) and a rotating ring (4) rotatably connected to the two connection plates (8); a driving wheel (9) is rotatably arranged between the two connection plates (8); the driving wheel (9) is connected to a driving motor (11) for driving the driving wheel (9) to rotate; a second receiving groove (10) is provided on a peripheral side wall of the driving wheel (9); the variable magnet (1) is fixed on the inner side of the rotating ring (4); a first receiving groove (5) extending in a circumferential direction is provided on an outer peripheral side wall of the rotating ring (4); the driving wheel (9) drives the rotating ring (4) to rotate via a transmission belt (6); and the transmission belt (6) is located in the first receiving groove (5) and the second receiving groove (10); A rolling groove (14) extending in a circumferential direction is respectively formed on the two end walls of the rotating ring (4); at least one insertion rod (15) is fixedly connected to the connecting plate (8); the insertion rod (15) is inserted into the rolling groove (14); and a rotating sleeve (16) is rotatably sleeved on the insertion rod (15); the rotating sleeve (16) contacts the inner wall of the rolling groove (14).

6. The wire rope defect detection device based on a variable magnetic field array according to claim 5, characterized in that: The adjustment mechanism further comprises a linear drive (13), a connecting block (12) being fixedly connected between the two connecting plates (8), the connecting block (12) being fixedly connected to an output end of the linear drive (13), and the linear drive (13) drives the variable magnet (1) to approach or move away from the detection space (2) during operation.

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