A wire rope nondestructive flaw detection method and detection system

Abstract

The application discloses a metal wire rope nondestructive flaw detection method and a detection system, relates to the technical field of metal wire rope nondestructive flaw detection, and comprises the following steps: leakage magnetic detection is carried out on the metal wire rope based on a Hall element to obtain a real-time detection signal wave; a waveform reference point is obtained based on the real-time detection signal; a signal fitting function is obtained based on the waveform reference point; an abnormal fluctuation threshold is obtained based on a first number of normal metal wire ropes; a real-time detection frequency is obtained based on the signal fitting function and the abnormal fluctuation threshold; an abnormal frequency threshold is obtained based on a second number of metal wire ropes containing damages; and damage judgment is performed on the metal wire rope based on the real-time detection frequency and the abnormal frequency threshold; and the application is used to solve the problem that the fluctuation of the collected signal and the interference of magnetic attachments are not considered in the prior art, resulting in low accuracy of the nondestructive flaw detection result.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of non-destructive testing of metal wire ropes, in particular to a non-destructive testing method and system for metal wire ropes. BACKGROUND

[0002] Metal wire ropes are affected by various factors and bear the combined effects of alternating loads, wear, corrosion, overload and other factors, and inevitably produce various damages, mainly including broken wires, wear, corrosion, fatigue, local shape abnormalities and loss of metal cross-sectional area; these defects can significantly reduce the load-carrying capacity of the steel wire rope, and once failure occurs, it may cause a catastrophic accident; therefore, it is necessary to detect the internal and external defects of the metal wire rope without damaging it, so as to achieve early detection and quantitative evaluation of the damage.

[0003] Currently, non-destructive testing of steel wire ropes mainly relies on magnetic flux leakage detection method based on magnetic principle; the method makes the steel wire rope locally reach a magnetic saturation state through a magnetizing device, when there is a defect, the magnetic field is distorted at the defect and generates a magnetic flux leakage field, and then the magnetic flux leakage field is detected by using a magnetic sensor, the data fluctuation signal of the magnetic sensor is complex, and if the steel wire rope surface contains magnetic attachments, the detected steel wire rope damage is caused by interference signals, so the accuracy of the non-destructive testing result is low; for example, in the patent application with the application publication number CN120385739A, a crane steel wire rope flaw detection device and method are disclosed, but this scheme fails to consider the fluctuation of the collected signal and the interference of the magnetic attachments, resulting in that the detected steel wire rope damage is caused by interference signals, i.e. the existing technology fails to consider the fluctuation of the collected signal and the interference of the magnetic attachments, resulting in low accuracy of the non-destructive testing result. SUMMARY

[0004] The present application aims to at least solve one of the technical problems in the prior art, by using a Hall element to perform magnetic flux leakage detection on a metal wire rope to obtain a real-time detection signal wave; obtaining a waveform reference point based on the real-time detection signal; obtaining a signal fitting function based on the waveform reference point; obtaining an abnormal fluctuation threshold based on a first number of normal metal wire ropes; obtaining a real-time detection frequency based on the signal fitting function and the abnormal fluctuation threshold; obtaining an abnormal frequency threshold based on a second number of metal wire ropes containing damages; and performing damage judgment on the metal wire rope based on the real-time detection frequency and the abnormal frequency threshold, to solve the problem that the existing technology fails to consider the fluctuation of the collected signal and the interference of the magnetic attachments, resulting in low accuracy of the non-destructive testing result.

[0005] To achieve the above-mentioned purpose, the present application provides a non-destructive testing method for metal wire ropes, comprising the following steps:

[0006] Performing magnetic flux leakage detection on a metal wire rope based on a Hall element to obtain a real-time detection signal wave;

[0007] acquiring waveform reference points based on the real-time detection signal;

[0008] acquiring a signal fitting function based on the waveform reference points;

[0009] acquiring an abnormal fluctuation threshold based on the first quantity of normal wire ropes;

[0010] acquiring a real-time detection frequency based on the signal fitting function and the abnormal fluctuation threshold;

[0011] acquiring an abnormal frequency threshold based on the second quantity of wire ropes containing damage;

[0012] judging the damage of the wire rope based on the real-time detection frequency and the abnormal frequency threshold.

[0013] Further, the real-time detection signal wave obtained by the magnetic flux leakage detection of the wire rope based on the Hall element comprises the following sub-steps:

[0014] Marking the position where the detection of the wire rope starts as the starting position, and marking the length from the starting position as the detection position;

[0015] Establishing a plane rectangular coordinate system with the detection position as the X-axis data and the voltage signal as the Y-axis data, and marking it as the signal coordinate system;

[0016] Obtaining the signal wave by drawing the data collected by the Hall element in the signal coordinate system, and marking it as the real-time detection signal wave.

[0017] Further, the waveform reference points obtained based on the real-time detection signal comprise the following sub-steps:

[0018] Marking a straight line parallel to the Y-axis as an interval straight line;

[0019] Drawing the third quantity of interval straight lines from the Y-axis of the signal coordinate system as the starting point, with a first distance as the interval, and in the positive direction of the X-axis of the signal coordinate system;

[0020] The interval straight lines divide the signal coordinate system into N equal spaces, and mark them as divided spaces;

[0021] In each divided space, obtaining the minimum value and the maximum value of the abscissa of the real-time detection signal wave, and marking them as the first abscissa value and the second abscissa value respectively;

[0022] Obtaining the minimum value and the maximum value of the ordinate of the real-time detection signal wave, and marking them as the first ordinate value and the second ordinate value respectively;

[0023] Mark the coordinate point with the first horizontal coordinate value and the first vertical coordinate value as a first coordinate point; mark the coordinate point with the second horizontal coordinate value and the first vertical coordinate value as a second coordinate point; mark the coordinate point with the second horizontal coordinate value and the second vertical coordinate value as a third coordinate point; and mark the coordinate point with the first horizontal coordinate value and the second vertical coordinate value as a fourth coordinate point;

[0024] Connect the first coordinate point and the second coordinate point to obtain a straight line, and mark the straight line as a first line segment; connect the second coordinate point and the third coordinate point to obtain a straight line, and mark the straight line as a second line segment; connect the third coordinate point and the fourth coordinate point to obtain a straight line, and mark the straight line as a third line segment; and connect the fourth coordinate point and the first coordinate point to obtain a straight line, and mark the straight line as a fourth line segment;

[0025] Obtain a rectangle formed by the first line segment, the second line segment, the third line segment, and the fourth line segment, and mark the rectangle as a division rectangle;

[0026] Obtain a midpoint of the division rectangle, and mark the midpoint as a waveform reference point.

[0027] Further, the obtaining of the signal fitting function based on the waveform reference point comprises the following sub-steps:

[0028] Obtain all waveform reference points of the division space;

[0029] Obtain a function by fitting all waveform reference points, and mark the function as a signal fitting function.

[0030] Further, the obtaining of the abnormal fluctuation threshold based on the first number of normal metal wire lines comprises the following sub-steps:

[0031] Mark the first number of normal metal wire lines as historical normal metal wire lines; and obtain a signal fitting function by regarding the historical normal metal wire lines as a metal wire rope to be detected, and mark the signal fitting function as a historical normal function;

[0032] Obtain a maximum value and a minimum value of a Y-axis in all historical normal functions, and mark the maximum value and the minimum value as a historical maximum value and a historical minimum value, respectively;

[0033] Mark the historical maximum value and the historical minimum value as historical normal values;

[0034] Obtain a target threshold by regarding the historical normal values as target values, and mark the target threshold as an abnormal fluctuation threshold.

[0035] Further, the threshold obtaining method comprises:

[0036] Obtain a range of target values, and uniformly divide the range of target values into a fourth number of intervals, and mark the fourth number of intervals as first division intervals;

[0037] Obtain the frequency of the target value in each first division interval, marked as the first division frequency;

[0038] Sort the first division frequency from left to right according to the minimum value of the corresponding first division interval from small to large;

[0039] Obtain the sum of the first division frequency, marked as the second division frequency;

[0040] Obtain the value of the fourth number of the second division frequency, marked as the third division frequency;

[0041] Set a smaller proportion value; obtain the product of the smaller proportion value and the third division frequency to obtain a value, marked as the smaller frequency threshold;

[0042] Mark the first division frequency less than the smaller frequency threshold as the fourth division frequency.

[0043] Determine whether the rightmost first division frequency is the fourth division frequency, if so, delete the rightmost fourth division frequency, continue to delete the fourth division frequency to the left, and stop until the rightmost first division frequency is not the fourth division frequency; After stopping, obtain the maximum value of the first division interval corresponding to the rightmost first division frequency, marked as the target threshold.

[0044] Further, the real-time detection frequency based on the signal fitting function and the abnormal fluctuation threshold comprises the following sub-steps:

[0045] Obtain the part of the signal fitting function whose ordinate is greater than the abnormal fluctuation threshold, marked as the defect part waveform;

[0046] Obtain one end point of the defect part waveform, marked as the starting end point; mark the other end point of the defect part waveform as the ending end point;

[0047] Draw fifth number of coordinate points with equal intervals on the defect part waveform between the starting end point and the ending end point, marked as the waveform coordinate point;

[0048] Connect adjacent waveform coordinate points to obtain a line segment, marked as a waveform line segment;

[0049] Obtain the slope of the waveform line segment, marked as the waveform slope;

[0050] Start from the starting end point and sequentially obtain the positive and negative of the waveform slope along the defect part waveform, count once when the positive and negative of the waveform slope changes, and the total sum of the count between the starting end point and the ending end point is marked as the real-time detection frequency.

[0051] Further, the abnormal frequency threshold based on the second number of metal wire ropes containing damage comprises the following sub-steps:

[0052] obtain a second number of real-time detection times of the damaged metal wire rope, marked as a historical detection time;

[0053] obtain a target threshold value based on the historical detection time as a target value, marked as an abnormal number threshold value.

[0054] Further, the damage judgment of the metal wire rope based on the real-time detection time and the abnormal number threshold value includes the following steps:

[0055] If no real-time waveform amplitude value appears, it indicates that the metal wire rope is not damaged;

[0056] If a real-time waveform amplitude value appears, it is judged whether the real-time detection time is less than or equal to the abnormal number threshold value. If yes, the metal wire rope is damaged. If no, the metal wire rope is interfered with to judge the situation.

[0057] The application also provides a metal wire rope non-destructive damage detection system, comprising a data acquisition module, a reference point acquisition module, a function fitting module, a fluctuation threshold value acquisition module, a detection data acquisition module, a number threshold value acquisition module, and a damage judgment module.

[0058] The data acquisition module is used to obtain a real-time detection signal wave based on the magnetic flux leakage detection of the metal wire rope by the Hall element.

[0059] The reference point acquisition module is used to obtain a waveform reference point based on the real-time detection signal.

[0060] The function fitting module is used to obtain a signal fitting function based on the waveform reference point.

[0061] The fluctuation threshold value acquisition module is used to obtain an abnormal fluctuation threshold value based on a first number of normal metal wire ropes.

[0062] The detection data acquisition module is used to obtain a real-time detection time based on the signal fitting function and the abnormal fluctuation threshold value.

[0063] The number threshold value acquisition module is used to obtain an abnormal number threshold value based on a second number of metal wire ropes with damage.

[0064] The damage judgment module is used to judge the damage of the metal wire rope based on the real-time detection time and the abnormal number threshold value.

[0065] The beneficial effects of the present application are that the present application obtains a real-time detection signal wave by carrying out magnetic flux leakage detection on the metal wire rope based on the Hall element, obtains a waveform reference point based on the real-time detection signal, obtains a signal fitting function based on the waveform reference point, obtains an abnormal fluctuation threshold based on a first number of normal metal wire ropes, obtains a real-time detection number based on the signal fitting function and the abnormal fluctuation threshold, obtains an abnormal number threshold based on a second number of metal wire ropes containing damage, and judges the damage of the metal wire rope based on the real-time detection number and the abnormal number threshold, which has the advantages that the fluctuation of the collected signal and the interference of the magnetic attachments can be considered, and the accuracy of the nondestructive damage detection result is improved.

[0066] The present application obtains a signal fitting function based on the waveform reference point, which has the advantages that the fluctuation of the collected signal can be excluded, and the accuracy of the nondestructive damage detection result is improved.

[0067] The present application obtains a real-time detection number based on the signal fitting function and the abnormal fluctuation threshold, which has the advantages that the interference of the magnetic attachments can be excluded, and the accuracy of the nondestructive damage detection result is improved. BRIEF DESCRIPTION OF DRAWINGS

[0068] Figure 1 It is a principle block diagram of the system of the present application.

[0069] Figure 2 It is a schematic diagram of the divided space of the present application.

[0070] Figure 3 It is a schematic diagram of the waveform reference point of the present application.

[0071] Figure 4 It is a schematic diagram of the signal fitting function of the present application.

[0072] Figure 5 It is a schematic diagram of the waveform coordinate point of the present application.

[0073] Figure 6 It is a schematic diagram of the waveform line segment of the present application.

[0074] Figure 7 It is a step flow chart of the method of the present application. DETAILED DESCRIPTION

[0075] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0076] Example 1, please refer to Figure 1As shown, the application provides a metal wire rope nondestructive testing system, comprising: a data acquisition module, a reference point acquisition module, a function fitting module, a fluctuation threshold acquisition module, a detection data acquisition module, a number threshold acquisition module, and a damage-containing judgment module.

[0077] The data acquisition module is configured to obtain a real-time detection signal wave based on the magnetic flux leakage detection of the metal wire rope by the Hall element; the detection device moves at a constant speed on the metal wire rope, and the Hall element can detect the strength of the magnetic flux leakage.

[0078] The data acquisition module is configured with a data acquisition strategy, which includes:

[0079] The position where the metal wire rope starts to be detected is marked as the starting position, and the length from the starting position is marked as the detection position.

[0080] The detection position is taken as the X-axis data, and the voltage signal is taken as the Y-axis data to establish a plane rectangular coordinate system, which is marked as the signal coordinate system.

[0081] The data collected by the Hall element is obtained in the signal coordinate system to obtain a signal wave, which is marked as a real-time detection signal wave; the real-time detection signal wave is the data detected by the Hall element.

[0082] In actual application, please refer to Figure 2 The obtained real-time detection signal wave.

[0083] The reference point acquisition module is configured to obtain a waveform reference point based on the real-time detection signal.

[0084] The reference point acquisition module is configured with a reference point acquisition strategy, which includes:

[0085] A straight line parallel to the Y-axis is marked as an interval straight line.

[0086] The Y-axis of the signal coordinate system is taken as the starting point, the interval is a first distance, and the third number of interval straight lines is drawn in the positive direction of the X-axis of the signal coordinate system; because the fluctuation of the real-time detection signal wave is large, the real-time detection signal wave is segmented and analyzed by drawing the interval straight lines, so the first distance should not be too large, and the third number should be able to cover the entire real-time detection signal wave; for example, the first distance is 10 cm, and the third number is 12.

[0087] The interval straight line divides the signal coordinate system into N equal spaces, which are marked as division spaces; when the third number is 12, N is 11.

[0088] In each division space, the minimum and maximum values of the abscissa of the real-time detection signal wave are obtained, which are marked as the first abscissa value and the second abscissa value, respectively.

[0089] Obtain the minimum value and the maximum value of the ordinate of the real-time detection signal wave, and mark them as a first ordinate value and a second ordinate value respectively;

[0090] Mark a coordinate point with the first abscissa value and the first ordinate value as a first coordinate point, a coordinate point with the second abscissa value and the first ordinate value as a second coordinate point, a coordinate point with the second abscissa value and the second ordinate value as a third coordinate point, and a coordinate point with the first abscissa value and the second ordinate value as a fourth coordinate point;

[0091] Connect the first coordinate point and the second coordinate point to obtain a straight line, mark it as a first line segment; connect the second coordinate point and the third coordinate point to obtain a straight line, mark it as a second line segment; connect the third coordinate point and the fourth coordinate point to obtain a straight line, mark it as a third line segment; and connect the fourth coordinate point and the first coordinate point to obtain a straight line, mark it as a fourth line segment;

[0092] Obtain a rectangle composed of the first line segment, the second line segment, the third line segment and the fourth line segment, and mark it as a division rectangle;

[0093] Obtain the midpoint of the division rectangle, mark it as a waveform reference point; take the waveform reference point as the midpoint of the real-time detection signal wave, represent the real-time detection signal wave through the waveform reference point, make the waveform smoother, and facilitate subsequent analysis of the real-time detection signal wave;

[0094] In actual application, please refer to Figure 3 a division rectangle obtained.

[0095] The function fitting module is configured with a function fitting strategy, and the function fitting strategy includes:

[0096] The function fitting module is configured with a function fitting strategy, and the function fitting strategy includes:

[0097] Obtain the waveform reference points of all division spaces;

[0098] Obtain a function by fitting all waveform reference points, mark it as a signal fitting function; represent the real-time detection signal wave through the signal fitting function, make the obtained data smoother, facilitate subsequent analysis of the real-time detection signal wave, and can eliminate fluctuations in the collected signal to improve the accuracy of non-destructive testing results.

[0099] In actual application, please refer to Figure 3 a signal fitting function obtained.

[0100] The fluctuation threshold acquisition module is configured to obtain an abnormal fluctuation threshold based on the first number of normal metal wires;

[0101] The fluctuation threshold obtaining module is configured with a fluctuation threshold obtaining strategy, and the fluctuation threshold obtaining strategy comprises:

[0102] The first number of normal wire lines are marked as historical normal wire lines, and the historical normal wire lines are regarded as the signal fitting function of the wire rope to be detected and marked as a historical normal function. If there is no magnetic leakage, the fluctuation is within a certain range. The first number of historical normal wire lines is used to obtain the fluctuation range of the historical normal function, so the first number is preferably larger. For example, the first number is 100;

[0103] The maximum and minimum values of the Y-axis in all historical normal functions are obtained and marked as a historical maximum value and a historical minimum value, respectively;

[0104] The historical maximum value and the historical minimum value are both marked as historical normal values. The fluctuation range of the historical normal function is obtained based on the historical normal values;

[0105] The historical normal values are regarded as target values to obtain a target threshold, which is marked as an abnormal fluctuation threshold;

[0106] In actual application, the target threshold obtained by regarding the historical normal values as target values is 110, and the abnormal fluctuation threshold is 110.

[0107] The threshold obtaining method comprises:

[0108] The range of the target values is obtained, and the range of the target values is evenly divided into a fourth number of intervals, which is marked as a first divided interval. The fourth number is 10, for example.

[0109] The frequency of the target values in each first divided interval is obtained, which is marked as a first divided frequency;

[0110] The first divided frequencies are sorted from left to right in ascending order according to the minimum values of the corresponding first divided intervals. The sorting is convenient for determining whether the edge target values are abnormal values;

[0111] The sum of the first divided frequencies is obtained, which is marked as a second divided frequency;

[0112] The second divided frequency is obtained by dividing the fourth number, which is marked as a third divided frequency;

[0113] A smaller proportion value is set. The product of the smaller proportion value and the third divided frequency is obtained, which is marked as a smaller frequency threshold. The smaller frequency threshold is used to obtain smaller first divided frequencies, so the smaller proportion value is set to be smaller. For example, the smaller proportion value is 0.2.

[0114] In practical application, the second division frequency 100 is obtained, the third division frequency calculated is 100 ÷ 10 = 10, and the smaller frequency threshold is 10 × 0.2 = 2, so the smaller frequency threshold is 2;

[0115] The first division frequency smaller than the smaller frequency threshold is marked as the fourth division frequency.

[0116] It is judged whether the rightmost first division frequency is the fourth division frequency, if yes, the rightmost fourth division frequency is deleted, the fourth division frequency is continuously deleted to the left until the rightmost first division frequency is not the fourth division frequency, and then the deletion is stopped; after the deletion is stopped, the maximum value of the first division interval corresponding to the rightmost first division frequency is obtained and marked as a target threshold; the target threshold is a target value which is too large and has a small distribution, and thus the maximum value of the accurate target value is obtained.

[0117] The detection data acquisition module is configured to obtain the real-time detection times based on the signal fitting function and the abnormal fluctuation threshold;

[0118] The detection data acquisition module is configured with a detection data acquisition strategy, and the detection data acquisition strategy comprises:

[0119] The part of the signal fitting function whose ordinate is greater than the abnormal fluctuation threshold is marked as a defect part waveform;

[0120] In practical application, please refer to Figure 5 As shown in the figure, the defect part waveform whose ordinate of the signal fitting function is greater than 110 is obtained.

[0121] An endpoint of the defect part waveform is obtained and marked as a starting endpoint; the other endpoint of the defect part waveform is marked as an ending endpoint;

[0122] Equal-interval fifth-number coordinate points are drawn on the defect part waveform between the starting endpoint and the ending endpoint, and marked as waveform coordinate points; the waveform coordinate points are drawn to facilitate the analysis of the change of the defect part waveform, and thus the fifth number should not be too small, for example, the fifth number is 16;

[0123] In practical application, please refer to Figure 5 As shown in the figure, the waveform coordinate points drawn.

[0124] The waveform line segment is obtained by connecting adjacent waveform coordinate points in the real-time waveform amplitude value, and marked as a waveform line segment; the waveform line segment is used to facilitate the analysis of the change of the defect part waveform;

[0125] In practical application, please refer to Figure 6 As shown in the figure, the waveform line segment drawn.

[0126] The slope of the waveform line segment is obtained and marked as a waveform slope;

[0127] Starting from the initial endpoint, the waveform slope is sequentially acquired along the defect section, indicating whether it is positive or negative. Each change in the slope is counted once. The total count from the initial endpoint to the final endpoint is recorded as the real-time detection count. If damage occurs at a certain location, the magnetic flux leakage waveform will be smooth with fewer peaks. The presence of magnetic deposits, iron blocks, etc., will also detect magnetic flux leakage. Since interfering objects are irregular, the magnetic flux leakage waveform is not smooth with many peaks. The real-time detection count represents the number of fluctuations. Therefore, the presence of interfering objects can be determined by counting the real-time detection count.

[0128] For practical applications, please refer to Figure 6 As shown, the number of real-time detections obtained is 1.

[0129] The number of occurrences threshold acquisition module is used to obtain the abnormal occurrences threshold based on a second number of damaged metal wire ropes;

[0130] The count threshold acquisition module is configured with a count threshold acquisition strategy, which includes:

[0131] Obtain the real-time detection count at a second number of damaged metal wire ropes and mark it as the historical detection count; the second number is to obtain the range of historical detection counts; therefore, the second number should not be set too large, for example, the second number is 100;

[0132] The target threshold is obtained by treating the number of historical detections as the target value and marking it as the abnormal number threshold; after excluding excessively large historical detections, the accurate maximum number of historical detections is obtained as the abnormal number threshold.

[0133] In practical applications, the threshold for the number of anomalies is 3.

[0134] The damage assessment module is used to assess the damage to metal wire ropes based on the number of real-time detections and anomaly thresholds.

[0135] The damage detection module is configured with damage detection strategies, which include:

[0136] If no real-time waveform amplitude value is displayed, it indicates that the metal wire rope is undamaged; if no magnetic leakage is detected, it indicates that the metal wire rope is normal.

[0137] If the real-time waveform amplitude value appears, it is judged whether the real-time detection times are less than or equal to the abnormal times threshold value, if yes, the metal wire rope appears damage, if not, the metal wire rope appears interference judgment condition; if damage appears at a certain position, the magnetic flux leakage waveform is smooth at this time, and the wave peak is less; if magnetic attachments, iron blocks and the like appear, the magnetic flux leakage can also be detected; the interference object is an irregular object, so the magnetic flux leakage waveform is not smooth, and the wave peak is more, and the real-time detection times represent the number of changes of fluctuations; therefore, whether the interference object appears can be judged by the real-time detection times; the abnormal times threshold value is the maximum real-time detection times of normal damage; therefore, it can be determined that the metal wire rope appears damage when the real-time detection times are less than or equal to the abnormal times threshold value; otherwise, interference can appear, and detection can be performed again after cleaning to judge whether damage appears;

[0138] In actual application, it is judged that the real-time detection times 1 are less than the abnormal times threshold value 3, and it is determined that the metal wire rope appears damage.

[0139] Embodiment 2, please refer to Figure 7 As shown in the figure, the application provides a metal wire rope nondestructive damage detection method, which comprises the following steps:

[0140] Step S1, based on the Hall element, the magnetic flux leakage detection of the metal wire rope is performed to obtain a real-time detection signal wave; step S1 comprises the following substeps:

[0141] Step S101, the position where the detection of the metal wire rope starts is marked as a starting position, and the length from the starting position is marked as a detection position;

[0142] Step S102, the detection position is taken as X-axis data, and the voltage signal is taken as Y-axis data to establish a plane rectangular coordinate system, which is marked as a signal coordinate system;

[0143] Step S103, the data collected by the Hall element is drawn in the signal coordinate system to obtain a signal wave, which is marked as a real-time detection signal wave.

[0144] Step S2, a waveform reference point is obtained based on the real-time detection signal; step S2 comprises the following substeps:

[0145] Step S201, a straight line parallel to the Y-axis is marked as an interval straight line;

[0146] Step S202, the Y-axis of the signal coordinate system is taken as a starting point, the interval is a first distance, and the third number of interval straight lines are drawn in the positive direction of the X-axis of the signal coordinate system;

[0147] Step S203, the interval straight line divides the signal coordinate system into N equal spaces, which are marked as divided spaces;

[0148] Step S204, in each division space, the minimum and maximum of the abscissa of the real-time detection signal wave are obtained, and are marked as a first abscissa value and a second abscissa value respectively;

[0149] Step S205, the minimum and maximum of the ordinate of the real-time detection signal wave are obtained, and are marked as a first ordinate value and a second ordinate value respectively;

[0150] Step S206, a coordinate point with the abscissa being the first abscissa value and the ordinate being the first ordinate value is marked as a first coordinate point; a coordinate point with the abscissa being the second abscissa value and the ordinate being the first ordinate value is marked as a second coordinate point; a coordinate point with the abscissa being the second abscissa value and the ordinate being the second ordinate value is marked as a third coordinate point; and a coordinate point with the abscissa being the first abscissa value and the ordinate being the second ordinate value is marked as a fourth coordinate point;

[0151] Step S207, a straight line is obtained by connecting the first coordinate point and the second coordinate point, and is marked as a first line segment; a straight line is obtained by connecting the second coordinate point and the third coordinate point, and is marked as a second line segment; a straight line is obtained by connecting the third coordinate point and the fourth coordinate point, and is marked as a third line segment; and a straight line is obtained by connecting the fourth coordinate point and the first coordinate point, and is marked as a fourth line segment;

[0152] Step S208, a rectangle formed by the first line segment, the second line segment, the third line segment and the fourth line segment is obtained, and is marked as a division rectangle;

[0153] Step S209, a midpoint of the division rectangle is obtained, and is marked as a waveform reference point.

[0154] Step S3, a signal fitting function is obtained based on the waveform reference point; step S3 includes the following substeps:

[0155] Step S301, waveform reference points of all division spaces are obtained;

[0156] Step S302, all waveform reference points are functionally fitted to obtain a function, which is marked as a signal fitting function.

[0157] Step S4, an abnormal fluctuation threshold is obtained based on the first number of normal metal wires; step S4 includes the following substeps:

[0158] Step S401, the first number of normal metal wires is marked as historical normal metal wires; the historical normal metal wires are regarded as metal wire ropes to be detected to obtain a signal fitting function, which is marked as a historical normal function;

[0159] Step S402, the maximum and minimum of the Y-axis in all historical normal functions are obtained, and are marked as a historical maximum value and a historical minimum value respectively;

[0160] Step S403, mark the historical maximum value and the historical minimum value as historical normal values;

[0161] Step S404, obtain a target threshold value by taking the historical normal values as target values, and mark the target threshold value as an abnormal fluctuation threshold value; Step S404 further includes the following sub-steps:

[0162] Step S40401, obtain a range of the target values, and evenly divide the range of the target values into a fourth number of intervals, and mark the intervals as first divided intervals;

[0163] Step S40402, obtain a frequency of the target values in each first divided interval, and mark the frequency as a first divided frequency;

[0164] Step S40403, sort the first divided frequencies from small to large according to the minimum values of the corresponding first divided intervals from left to right;

[0165] Step S40404, obtain a sum of the first divided frequencies, and mark the sum as a second divided frequency;

[0166] Step S40405, obtain a value by dividing the second divided frequency by the fourth number, and mark the value as a third divided frequency;

[0167] Step S40406, set a smaller proportion value; obtain a value by multiplying the smaller proportion value and the third divided frequency, and mark the value as a smaller frequency threshold value;

[0168] Step S40407, mark the first divided frequencies smaller than the smaller frequency threshold value as fourth divided frequencies.

[0169] Step S40408, determine whether the rightmost first divided frequency is a fourth divided frequency; if so, delete the rightmost fourth divided frequency, and continue to delete the fourth divided frequencies to the left until the rightmost first divided frequency is not a fourth divided frequency; after stopping, obtain a maximum value of the first divided interval corresponding to the rightmost first divided frequency, and mark the maximum value as a target threshold value.

[0170] Step S5, obtain a real-time detection number based on the signal fitting function and the abnormal fluctuation threshold value; Step S5 includes the following sub-steps:

[0171] Step S501, obtain a part of the signal fitting function with a vertical coordinate greater than the abnormal fluctuation threshold value, and mark the part as a defective part waveform;

[0172] Step S502, obtain one end point of the defective part waveform, and mark the end point as a starting end point; mark the other end point of the defective part waveform as an ending end point;

[0173] Step S503, drawing a fifth number of coordinate points equally spaced on the defect part waveform between the starting endpoint and the ending endpoint, marked as waveform coordinate points;

[0174] Step S504, connecting adjacent waveform coordinate points with real-time waveform amplitude values to obtain a line segment, marked as a waveform line segment;

[0175] Step S505, obtaining the slope of the waveform line segment, marked as the waveform slope;

[0176] Step S506, starting from the starting endpoint, sequentially obtaining the positive and negative conditions of the waveform slope along the defect part waveform, and counting once when the positive and negative conditions of the waveform slope change, and obtaining the total sum of the counts between the starting endpoint and the ending endpoint, marked as the real-time detection times.

[0177] Step S6, obtaining an abnormality times threshold value based on the second number of damaged metal wire ropes; Step S6 includes the following sub-steps:

[0178] Step S601, obtaining the real-time detection times at the second number of damaged metal wire ropes, marked as the historical detection times;

[0179] Step S602, obtaining a target threshold value taking the historical detection times as a target value, marked as the abnormality times threshold value.

[0180] Step S7, judging the damage of the metal wire rope based on the real-time detection times and the abnormality times threshold value; Step S7 includes the following sub-steps:

[0181] Step S701, if no real-time waveform amplitude value appears, indicating that the metal wire rope is undamaged;

[0182] Step S702, if a real-time waveform amplitude value appears, judging whether the real-time detection times are less than or equal to the abnormality times threshold value, if yes, the metal wire rope is damaged, if not, the metal wire rope appears an interference judgment condition.

[0183] Those skilled in the art will appreciate that embodiments of the present application can be readily used as a method, a system or a computer program product. Accordingly, the present application can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application can take the form of a computer program product on one or more computer-usable storage media (or computer- readable storage media) having computer-usable program code embodied in the medium. The medium can be any available storage media that can be accessed by a computer. By way of example, and not limitation, such computer-usable storage media can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other storage medium that can be used to carry or store desired computer program code in the form of instructions or data structures and that can be accessed by a computer. Also, the present application can be embodied in a computer program product that can be traded as goods or merchandise, through the storage medium described above or any other suitable medium. When the computer program code is executed by a computer, a series of instructions or a series of operations is performed. Also, the present application can be embodied in a computer program product that can be traded as goods or merchandise, through the storage medium described above or any other suitable medium. When the computer program code is executed by a computer, a series of instructions or a series of operations is performed. Figure 1 one or more flows and / or blocks Figure 1 one or more flows and / or blocks

[0184] In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method can be implemented in other manners. The embodiments described above are merely specific implementation manners of the present application, and the partition shown or discussed as above between the units is merely logical function division, and there can be another partition manner in actual implementation. For example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed coupling or direct coupling or communication connection between the units can be indirect coupling or communication connection through some interface, and can be electrical, mechanical or other forms.

Claims

1. A method for non-destructive inspection of a wire rope, characterized in that, The method comprises the following steps: Obtaining a real-time detection signal wave by performing magnetic flux leakage detection on the metal wire rope based on the Hall element; Obtaining a waveform reference point based on the real-time detection signal; Obtaining a signal fitting function based on the waveform reference point; Obtaining an abnormal fluctuation threshold based on a first number of normal metal wire ropes; Obtaining a real-time detection frequency based on the signal fitting function and the abnormal fluctuation threshold; Obtaining an abnormal frequency threshold based on a second number of metal wire ropes containing damage; Performing damage judgment on the metal wire rope based on the real-time detection frequency and the abnormal frequency threshold; The method for obtaining the waveform reference point based on the real-time detection signal comprises the following sub-steps: Marking a straight line parallel to the Y axis as an interval straight line; Drawing a third number of interval straight lines from the Y axis of the signal coordinate system as a starting point at an interval of a first distance to the positive direction of the X axis of the signal coordinate system; The interval straight line divides the signal coordinate system into N equal spaces, which are marked as division spaces; In each division space, the minimum and maximum values of the horizontal coordinates of the real-time detection signal wave are obtained, which are marked as a first horizontal coordinate value and a second horizontal coordinate value, respectively; The minimum and maximum values of the vertical coordinates of the real-time detection signal wave are obtained, which are marked as a first vertical coordinate value and a second vertical coordinate value, respectively; A coordinate point with a horizontal coordinate of the first horizontal coordinate value and a vertical coordinate of the first vertical coordinate value is marked as a first coordinate point; a coordinate point with a horizontal coordinate of the second horizontal coordinate value and a vertical coordinate of the first vertical coordinate value is marked as a second coordinate point; a coordinate point with a horizontal coordinate of the second horizontal coordinate value and a vertical coordinate of the second vertical coordinate value is marked as a third coordinate point; and a coordinate point with a horizontal coordinate of the first horizontal coordinate value and a vertical coordinate of the second vertical coordinate value is marked as a fourth coordinate point; A straight line connecting the first coordinate point and the second coordinate point is obtained, which is marked as a first line segment; and a straight line connecting the second coordinate point and the third coordinate point is obtained, which is marked as a second line segment; A straight line connecting the third coordinate point and the fourth coordinate point is obtained, which is marked as a third line segment; and a straight line connecting the fourth coordinate point and the first coordinate point is obtained, which is marked as a fourth line segment; A rectangle formed by the first line segment, the second line segment, the third line segment and the fourth line segment is obtained, which is marked as a division rectangle; A midpoint of the division rectangle is obtained, which is marked as a waveform reference point; The method for obtaining the real-time detection frequency based on the signal fitting function and the abnormal fluctuation threshold comprises the following sub-steps: Obtaining a defective part waveform of the signal fitting function whose vertical coordinate is greater than the abnormal fluctuation threshold; Obtaining a starting end point of the defective part waveform; Marking another end point of the defective part waveform as an ending end point; Drawing a fifth number of coordinate points equally spaced on the defective part waveform between the starting end point and the ending end point, which are marked as waveform coordinate points; Connecting adjacent waveform coordinate points with real-time waveform amplitude values to obtain line segments, which are marked as waveform line segments; Obtaining the slope of the waveform line segment, which is marked as a waveform slope; Starting from the starting end point, the positive and negative situations of the waveform slope are sequentially obtained along the defective part waveform; when the positive and negative situations of the waveform slope change, the count is incremented by one; and the total sum of the count between the starting end point and the ending end point is marked as a real-time detection frequency.

2. The method of claim 1, wherein the metal wire rope is a steel wire rope. The method for obtaining the real-time detection signal wave by performing magnetic flux leakage detection on the metal wire rope based on the Hall element comprises the following sub-steps: Mark the position where the detection of the metal wire rope starts as a starting position, and mark the length from the starting position as a detection position; Establish a plane rectangular coordinate system with the detection position as the X-axis data and the voltage signal as the Y-axis data, and mark it as a signal coordinate system; Draw the signal wave obtained by the data collected by the Hall element in the signal coordinate system, and mark it as a real-time detection signal wave.

3. The method of claim 2, wherein the metal wire rope is a steel wire rope. The signal fitting function based on the waveform reference points includes the following sub-steps: Obtain all the waveform reference points of the divided space; Obtain the function by fitting all the waveform reference points, and mark it as the signal fitting function.

4. The method of claim 3, wherein the metal wire rope is a steel wire rope. The abnormal fluctuation threshold based on the first number of normal metal wire lines includes the following sub-steps: Mark the first number of normal metal wire lines as historical normal metal wire lines; obtain the signal fitting function by regarding the historical normal metal wire lines as the metal wire rope to be detected, and mark it as the historical normal function; Obtain the maximum and minimum values of the Y-axis in all historical normal functions, and mark them as the historical maximum value and the historical minimum value, respectively; Mark the historical maximum value and the historical minimum value as historical normal values; Obtain the target threshold value by regarding the historical normal value as the target value, and mark it as the abnormal fluctuation threshold value.

5. The method of claim 4, wherein the step of detecting the defect of the wire rope is performed by using a method of detecting a defect of a wire rope according to any one of claims 1 to 3. The threshold value acquisition method includes: Obtain the range of the target value, evenly divide the range of the target value into a fourth number of intervals, and mark it as the first division interval; Obtain the frequency of the target value in each first division interval, and mark it as the first division frequency; Sort the first division frequency from left to right according to the minimum value of the corresponding first division interval from small to large; Obtain the sum of the first division frequency, and mark it as the second division frequency; Obtain the value by dividing the second division frequency by the fourth number, and mark it as the third division frequency; Set a smaller proportion value; obtain the product of the smaller proportion value and the third division frequency to obtain a value, and mark it as the smaller frequency threshold value; Mark the first division frequency less than the smaller frequency threshold value as the fourth division frequency; Determine whether the rightmost first division frequency is the fourth division frequency, if so, delete the rightmost fourth division frequency, continue to delete the fourth division frequency to the left, and stop until the rightmost first division frequency is not the fourth division frequency; after stopping, obtain the maximum value of the first division interval corresponding to the rightmost first division frequency, and mark it as the target threshold value.

6. The method of claim 5, wherein the metal wire rope is a steel wire rope. The abnormal number threshold value based on the second number of metal wire ropes with damage includes the following sub-steps: Obtain the real-time detection number at the second number of metal wire ropes with damage, and mark it as the historical detection number; Obtain the target threshold value by regarding the historical detection number as the target value, and mark it as the abnormal number threshold value.

7. The method of claim 6, wherein the metal wire rope is a steel wire rope. The damage judgment of the metal wire rope based on the real-time detection number and the abnormal number threshold value includes the following steps: If there is no real-time waveform amplitude value, it indicates that the metal wire rope is undamaged; If there is a real-time waveform amplitude value, determine whether the real-time detection number is less than or equal to the abnormal number threshold value, if so, the metal wire rope is damaged, if not, the metal wire rope is interfered.

8. A metal wire rope nondestructive inspection system for implementing the metal wire rope nondestructive inspection method according to any one of claims 1 to 7, characterized by, It includes a data acquisition module, a reference point acquisition module, a function fitting module, a fluctuation threshold acquisition module, a detection data acquisition module, a number threshold acquisition module, and a damaged judgment module. The data acquisition module is configured to acquire a real-time detection signal wave based on the Hall element for the metal wire rope magnetic flux leakage detection; The reference point acquisition module is configured to acquire a waveform reference point based on the real-time detection signal; The function fitting module is configured to acquire a signal fitting function based on the waveform reference point; The fluctuation threshold acquisition module is configured to acquire an abnormal fluctuation threshold based on the first number of normal metal wire ropes; The detection data acquisition module is configured to acquire a real-time detection number based on the signal fitting function and the abnormal fluctuation threshold; The number threshold acquisition module is configured to acquire an abnormal number threshold based on the second number of metal wire ropes containing damage; The damage judgment module is configured to judge the damage of the metal wire rope based on the real-time detection number and the abnormal number threshold.

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