Nondestructive flaw detection method and detection system for metal wire rope

Abstract

The invention discloses a metal wire rope nondestructive flaw detection method and system, and relates to the technical field of metal wire rope nondestructive flaw detection, and the method comprises the following steps: carrying out magnetic flux leakage detection on a metal wire rope based on a Hall element to obtain a real-time detection signal wave; acquiring a waveform reference point based on the real-time detection signal; acquiring a signal fitting function based on the waveform reference point; obtaining an abnormal fluctuation threshold value based on the first number of normal metal wires; acquiring real-time detection times based on the signal fitting function and the abnormal fluctuation threshold value; obtaining an abnormal frequency threshold value based on the second number of damaged metal wire ropes; performing damage judgment on the metal wire rope based on the real-time detection times and the abnormal times threshold; the method is used for solving the problem that in the prior art, fluctuation of collected signals and interference of magnetic attachments are not considered, so that the accuracy of a nondestructive inspection result is low.

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 catastrophic accidents; 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; 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 surface of the steel wire rope contains magnetic attachments, the detected damage of the steel wire rope 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 damage of the steel wire rope is caused by interference signals, that is, 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

[0003] 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 damage; 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.

[0004] To achieve the above-mentioned purpose, the present application provides a non-destructive testing method for metal wire ropes, comprising the following steps: obtaining a real-time detection signal wave by performing magnetic flux leakage detection on a metal wire rope based on a Hall element; obtaining a waveform reference point based on the real-time detection signal; acquiring a signal fitting function based on the waveform reference points; acquiring an abnormal fluctuation threshold based on the first number of normal wire ropes; acquiring a real-time detection frequency based on the signal fitting function and the abnormal fluctuation threshold; acquiring an abnormal frequency threshold based on the second number of wire ropes with damage; judging the damage of the wire rope based on the real-time detection frequency and the abnormal frequency threshold.

[0005] Further, the real-time detection signal wave obtained by the magnetic flux leakage detection of the wire rope based on the Hall element includes the following sub-steps: marking the position where the detection of the wire rope starts as a starting position, and marking the length from the starting position as a detection position; 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 a signal coordinate system; obtaining the signal wave by drawing the data collected by the Hall element in the signal coordinate system, and marking it as a real-time detection signal wave.

[0006] Further, the waveform reference points obtained based on the real-time detection signal include the following sub-steps: marking a straight line parallel to the Y-axis as an interval straight line; drawing the third number of interval straight lines from the Y-axis of the signal coordinate system as the starting point and with the first distance as the interval to the positive direction of the X-axis of the signal coordinate system; dividing the signal coordinate system into N equal spaces by the interval straight lines, and marking them as divided spaces; 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; 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; marking the coordinate point with the first abscissa value as the abscissa and the first ordinate value as the ordinate as the first coordinate point, marking the coordinate point with the second abscissa value as the abscissa and the first ordinate value as the ordinate as the second coordinate point, marking the coordinate point with the second abscissa value as the abscissa and the second ordinate value as the ordinate as the third coordinate point, and marking the coordinate point with the first abscissa value as the abscissa and the second ordinate value as the ordinate as the fourth coordinate point; connecting the first coordinate point and the second coordinate point to obtain a straight line, marking it as the first line segment; connecting the second coordinate point and the third coordinate point to obtain a straight line, marking it as the second line segment; connecting the third coordinate point and the fourth coordinate point to obtain a straight line, marking it as the third line segment; and connecting the fourth coordinate point and the first coordinate point to obtain a straight line, marking it as the fourth line segment; Obtaining a rectangle composed of the first line segment, the second line segment, the third line segment and the fourth line segment, and marking it as a division rectangle; Obtaining a midpoint of the division rectangle, and marking it as a waveform reference point.

[0007] Further, obtaining the signal fitting function based on the waveform reference point comprises the following sub-steps: Obtaining all waveform reference points of the division space; Performing function fitting on all waveform reference points to obtain a function, and marking it as a signal fitting function.

[0008] Further, obtaining the abnormal fluctuation threshold based on the first number of normal wire lines comprises the following sub-steps: Marking the first number of normal wire lines as historical normal wire lines; regarding the historical normal wire lines as the metal wire rope to be detected to obtain a signal fitting function, and marking it as a historical normal function; Obtaining the maximum value and the minimum value of the Y-axis in all historical normal functions, and marking them as a historical maximum value and a historical minimum value respectively; Marking the historical maximum value and the historical minimum value as historical normal values; Regarding the historical normal values as target values to obtain a target threshold, and marking it as an abnormal fluctuation threshold.

[0009] Further, the threshold obtaining method comprises: Obtaining a range of target values, and uniformly dividing the range of target values into a fourth number of intervals, and marking them as first division intervals; Obtaining the frequency of target values in each first division interval, and marking it as a first division frequency; Sorting the first division frequencies from left to right according to the minimum values of the corresponding first division intervals from small to large; Obtaining the sum of the first division frequencies, and marking it as a second division frequency; Obtaining a value from the fourth number of the second division frequency, and marking it as a third division frequency; Setting a smaller proportion value; obtaining a value from the product of the smaller proportion value and the third division frequency, and marking it as a smaller frequency threshold; Marking the first division frequencies smaller than the smaller frequency threshold as fourth division frequencies.

[0010] Determining whether the rightmost first division frequency is the fourth division frequency, if yes, deleting the rightmost fourth division frequency, and continuously deleting the fourth division frequencies to the left until stopping when the rightmost first division frequency is not the fourth division frequency; after stopping, obtaining the maximum value of the first division interval corresponding to the rightmost first division frequency, and marking it as a target threshold.

[0011] Further, the acquiring the real-time detection times based on the signal fitting function and the abnormal fluctuation threshold comprises the following sub-steps: acquiring a part of the ordinate of the signal fitting function greater than the abnormal fluctuation threshold, and marking as a defective part waveform; acquiring one end point of the defective part waveform, and marking as a starting end point; and acquiring another end point of the defective part waveform, and marking as an ending end point; drawing fifth-numbered coordinate points of equal intervals on the defective part waveform between the starting end point and the ending end point, and marking as waveform coordinate points; connecting adjacent waveform coordinate points with the real-time waveform amplitude value to obtain a line segment, and marking as a waveform line segment; acquiring the slope of the waveform line segment, and marking as a waveform slope; starting from the starting end point, sequentially acquiring the positive and negative conditions of the waveform slope along the defective part waveform, counting once when the positive and negative conditions of the waveform slope change, and taking the total sum of the counts between the starting end point and the ending end point as the real-time detection times.

[0012] Further, the acquiring the abnormal times threshold based on the second-numbered metal wire ropes with damages comprises the following sub-steps: acquiring the real-time detection times at the second-numbered metal wire ropes with damages, and marking as historical detection times; taking the historical detection times as a target value to acquire a target threshold, and marking as the abnormal times threshold.

[0013] Further, the damage judgment of the metal wire rope based on the real-time detection times and the abnormal times threshold comprises the following steps: if no real-time waveform amplitude value appears, it indicates that the metal wire rope has no damage; 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, if yes, the metal wire rope has damage, and if not, the metal wire rope has an interference judgment condition.

[0014] The application also provides a metal wire rope nondestructive damage detection 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 times threshold acquisition module, and a damage judgment module; The data acquisition module is used for acquiring a real-time detection signal wave based on the magnetic flux leakage detection of the metal wire rope by the Hall element; The reference point acquisition module is used for acquiring a waveform reference point based on the real-time detection signal; The function fitting module is used for acquiring a signal fitting function based on the waveform reference point; The fluctuation threshold acquisition module is used for acquiring an abnormal fluctuation threshold based on the first-numbered normal metal wire ropes; The detection data acquisition module is configured to acquire the real-time detection times based on the signal fitting function and the abnormal fluctuation threshold value; The number threshold value acquisition module is configured to acquire the abnormal number threshold value based on the second number of metal wire ropes containing damages. The damage judgment module is configured to judge the damages of the metal wire rope based on the real-time detection times and the abnormal number threshold value.

[0015] The present application has the following advantages: the present application acquires the real-time detection signal wave by leakage magnetic detection of the metal wire rope based on the Hall element, acquires the waveform reference point based on the real-time detection signal, acquires the signal fitting function based on the waveform reference point, acquires the abnormal fluctuation threshold value based on the first number of normal metal wire ropes, acquires the real-time detection times based on the signal fitting function and the abnormal fluctuation threshold value, acquires the abnormal number threshold value based on the second number of metal wire ropes containing damages, and judges the damages of the metal wire rope based on the real-time detection times and the abnormal number threshold value, which can consider the fluctuation of the collected signal and the interference of the magnetic attachments, and improve the accuracy of the nondestructive damage detection result. The present application acquires the signal fitting function based on the waveform reference point, which can eliminate the fluctuation of the collected signal and improve the accuracy of the nondestructive damage detection result. The present application acquires the real-time detection times based on the signal fitting function and the abnormal fluctuation threshold value, which can eliminate the interference of the magnetic attachments and improve the accuracy of the nondestructive damage detection result. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 It is a principle block diagram of the system of the present application; Figure 2 It is a schematic diagram of the divided space of the present application; Figure 3 It is a schematic diagram of the waveform reference point of the present application; Figure 4 It is a schematic diagram of the signal fitting function of the present application; Figure 5 It is a schematic diagram of the waveform coordinate point of the present application; Figure 6 It is a schematic diagram of the waveform line segment of the present application; Figure 7 It is a step flow chart of the method of the present application. DETAILED DESCRIPTION

[0017] 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 a 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.

[0018] Embodiment 1, please refer to Figure 1 As shown in the figure, 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 judgment module; The data acquisition module is used for acquiring real-time detection signal waves 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.

[0019] The data acquisition module is configured with a data acquisition strategy, and the data acquisition strategy comprises: 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; 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 a signal coordinate system; 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; the real-time detection signal wave is the data detected by the Hall element; In practical application, please refer to Figure 2 As shown in the figure, the real-time detection signal wave is obtained.

[0020] The reference point acquisition module is used for acquiring waveform reference points based on the real-time detection signal; The reference point acquisition module is configured with a reference point acquisition strategy, and the reference point acquisition strategy comprises: A straight line parallel to the Y-axis is marked as an interval straight line; 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 are 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; The interval straight line divides the signal coordinate system into N equal spaces, which are marked as division spaces; N is the division space, for example, when the third number is 12, N is 11; 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; The minimum and maximum values of the ordinate of the real-time detection signal wave are obtained, which are marked as the first ordinate value and the second ordinate value, respectively; 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; 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; 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; Obtain a midpoint of the division rectangle, and mark the midpoint as a waveform reference point; take the waveform reference point as a 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; In actual application, refer to FIG. 1. Figure 3 In FIG. 1, a division rectangle is obtained.

[0021] The function fitting module is configured with a function fitting strategy, and the function fitting strategy includes: The function fitting module is configured with a function fitting strategy, and the function fitting strategy includes: Obtain waveform reference points of all division spaces; Obtain a function by fitting all the waveform reference points, and mark the function 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, can eliminate fluctuations of the collected signal, and improve accuracy of the nondestructive testing result.

[0022] In actual application, refer to FIG. 1. Figure 3 In FIG. 1, a signal fitting function is obtained.

[0023] The fluctuation threshold value acquisition module is configured with a fluctuation threshold value acquisition strategy, and the fluctuation threshold value acquisition strategy includes: The fluctuation threshold value acquisition module is configured with a fluctuation threshold value acquisition strategy, and the fluctuation threshold value acquisition strategy includes: Mark the first number of normal metal wires as historical normal metal wires; take the historical normal metal wires as the metal wire to be detected to obtain a signal fitting function, and mark the signal fitting function as a historical normal function; if there is no magnetic flux leakage, the fluctuation is within a certain range, the first number of historical normal metal wires is used to obtain a fluctuation range of the historical normal function, and therefore the first number is preferably larger, for example, the first number is 100; Obtain the maximum and minimum values of the Y-axis in all historical normal functions, respectively marked as historical maximum and historical minimum; Mark the historical maximum and historical minimum as historical normal values; obtain the fluctuation range of the historical normal function based on the 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; In actual application, if the target threshold value obtained by regarding the historical normal value as the target value is 110, the abnormal fluctuation threshold value is 110.

[0024] The threshold value obtaining method comprises: Obtain the range of the target value, and uniformly divide the range of the target value into fourth number of intervals, marked as first divided intervals; divide the fourth number of first divided intervals to observe the distribution of the target value, for example, the fourth number is 10; Obtain the frequency of the target value in each first divided interval, marked as first divided frequency; Sort the first divided frequency from left to right according to the minimum value of the corresponding first divided interval from small to large; sorting is convenient for determining whether the edge target value is an abnormal value; Obtain the sum of the first divided frequency, marked as second divided frequency; Obtain a value by dividing the second divided frequency by the fourth number, marked as third divided frequency; Set a smaller proportion value; obtain a value by multiplying the smaller proportion value and the third divided frequency, marked as smaller frequency threshold value; the smaller frequency threshold value is used to obtain smaller first divided frequency, so the smaller proportion value is set to be smaller, for example, the smaller proportion value is 0.2; In actual application, if the second divided frequency is 100, the calculated third divided frequency is: 100 ÷ 10 = 10; and the smaller frequency threshold value is: 10 × 0.2 = 2, so the smaller frequency threshold value is 2; Mark the first divided frequency smaller than the smaller frequency threshold value as fourth divided frequency.

[0025] Determine whether the rightmost first divided frequency is the fourth divided frequency, if yes, delete the rightmost fourth divided frequency, and continue to delete the fourth divided frequency to the left until the rightmost first divided frequency is not the fourth divided frequency, then stop; after stopping, obtain the maximum value of the first divided interval corresponding to the rightmost first divided frequency, marked as target threshold value; the target threshold value deletes the target value that is too large and has small distribution, and then obtains the maximum value of the accurate target value.

[0026] The detection data obtaining module is configured to obtain the real-time detection times based on the signal fitting function and the abnormal fluctuation threshold value; The detection data obtaining module is configured with a detection data obtaining strategy, and the detection data obtaining strategy comprises: The part of the ordinate of the signal fitting function greater than the abnormal fluctuation threshold is marked as a defect part waveform; In practical applications, please refer to Figure 5 As shown in the figure, the defect part waveform with an ordinate greater than 110 of the signal fitting function is obtained.

[0027] 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; A fifth number of coordinate points equally spaced on the defect part waveform between the starting endpoint and the ending endpoint are drawn and marked as waveform coordinate points; the fifth number is set not to be too small, for example, the fifth number is 16, so that the change of the defect part waveform can be analyzed conveniently. In practical applications, please refer to Figure 5 As shown in the figure, the waveform coordinate points drawn are shown.

[0028] A line segment is obtained by connecting adjacent waveform coordinate points in the real-time waveform amplitude value, and is marked as a waveform line segment; the waveform line segment is used to analyze the change of the defect part waveform conveniently. In practical applications, please refer to Figure 6 As shown in the figure, the waveform line segments drawn are shown.

[0029] The slope of the waveform line segment is obtained and marked as a waveform slope; The positive and negative situations of the waveform slope are obtained in sequence from the starting endpoint along the defect part waveform, and when the positive and negative situations of the waveform slope change, the count is incremented by one; the total sum of the counts between the starting endpoint and the ending endpoint is marked as a real-time detection number; if a damage occurs at a certain position, the magnetic flux leakage waveform is smooth, and the wave peaks are less; if magnetic attachments, iron blocks, etc. appear, the magnetic flux leakage is also detected; the interference object is an irregular object, so the magnetic flux leakage waveform is not smooth, and the wave peaks are more; the real-time detection number represents the number of changes in fluctuations; therefore, whether an interference object appears can be determined by the real-time detection number. In practical applications, please refer to Figure 6 As shown in the figure, the obtained real-time detection number is 1.

[0030] The number threshold value acquisition module is configured to obtain an abnormal number threshold value based on a second number of metal wire ropes containing damages; The number threshold value acquisition module is configured with a number threshold value acquisition strategy, and the number threshold value acquisition strategy includes: The real-time detection numbers at the second number of metal wire ropes containing damages are obtained and marked as historical detection numbers; the second number is used to obtain the range of the historical detection numbers; therefore, the second number is set not to be too large, for example, the second number is 100. 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.

[0031] In practical applications, the threshold for the number of anomalies is 3.

[0032] 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. The damage detection module is configured with damage detection strategies, which include: 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. If a real-time waveform amplitude value is observed, determine if the number of real-time detections is less than or equal to the abnormal number threshold. If so, the metal wire rope is damaged; otherwise, interference is present. If damage occurs at a certain location, the leakage magnetic field waveform will be smooth with fewer peaks. Magnetic deposits, iron blocks, etc., will also detect leakage magnetic field. Interfering objects are irregular, resulting in an uneven leakage magnetic field waveform with many peaks. The number of real-time detections represents the frequency of fluctuations. Therefore, the number of real-time detections can be used to determine if an interfering object is present. The abnormal number threshold is the maximum number of real-time detections for normal damage. Therefore, if the number of real-time detections is less than or equal to the abnormal number threshold, the metal wire rope is considered damaged. Otherwise, interference may occur, and cleaning and re-detection can be performed to determine if damage has occurred. In practical applications, if the number of real-time detections (1) is less than the abnormal number threshold (3), then the metal wire rope is considered to be damaged.

[0033] Example 2, please refer to Figure 7 As shown, this application provides a non-destructive testing method for metal wire ropes, including the following steps: Step S1 involves obtaining a real-time detection signal wave by performing leakage magnetic field detection on the metal wire rope based on a Hall element; Step S1 includes the following sub-steps: Step S101: Mark the starting position of the metal wire rope detection as the starting position, and mark the length from the starting position as the detection position; Step S102: Establish a Cartesian coordinate system with the detection position as the X-axis data and the voltage signal as the Y-axis data, and mark it as the signal coordinate system; Step S103: Obtain the data collected by the Hall element, plot it in the signal coordinate system to obtain the signal wave, and mark it as the real-time detection signal wave.

[0034] Step S2, acquire waveform reference points based on real-time detection signals; Step S2 includes the following sub-steps: Step S201, a straight line parallel to the Y axis is marked as an interval line; Step S202, a third number of interval lines are drawn from the Y axis of the signal coordinate system to the positive direction of the X axis of the signal coordinate system with a first distance as an interval; Step S203, the interval lines divide the signal coordinate system into N equal spaces, which are marked as division spaces; Step S204, in each division space, the minimum and maximum values of the real-time detection signal wave abscissa are obtained, which are marked as a first abscissa value and a second abscissa value, respectively; Step S205, the minimum and maximum values of the real-time detection signal wave ordinate are obtained, which are marked as a first ordinate value and a second ordinate value, respectively; 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; 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; Step S207, a straight line connecting the first coordinate point and the second coordinate point is obtained, which is marked as a first line segment; 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; a straight line connecting the fourth coordinate point and the first coordinate point is obtained, which is marked as a fourth line segment; 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, which is marked as a division rectangle; Step S209, a midpoint of the division rectangle is obtained, which is marked as a waveform reference point.

[0035] Step S3, a signal fitting function is obtained based on the waveform reference point; Step S3 includes the following sub-steps: Step S301, waveform reference points of all division spaces are obtained; Step S302, a function is obtained by function fitting of all waveform reference points, which is marked as a signal fitting function.

[0036] Step S4, an abnormal fluctuation threshold is obtained based on the first number of normal metal wire lines; Step S4 includes the following sub-steps: Step S401, the first number of normal metal wire lines is marked as historical normal metal wire lines; the historical normal metal wire lines are regarded as metal wire ropes to be detected to obtain a signal fitting function, which is marked as a historical normal function; Step S402, obtain the maximum value and the minimum value of the Y-axis in all historical normal functions, and mark them as historical maximum value and historical minimum value respectively; Step S403, mark the historical maximum value and the historical minimum value as historical normal values; Step S404, obtain a target threshold value by taking the historical normal values as target values, and mark it as an abnormal fluctuation threshold value; Step S404 further includes the following sub-steps: 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 them as first divided intervals; Step S40402, obtain the frequency of the target values in each first divided interval, and mark it as a first divided frequency; 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; Step S40404, obtain the sum of the first divided frequencies, and mark it as a second divided frequency; Step S40405, obtain a value by taking the second divided frequency to the fourth number, and mark it as a third divided frequency; Step S40406, set a smaller proportion value; obtain a value by taking the product of the smaller proportion value and the third divided frequency, and mark it as a smaller frequency threshold value; Step S40407, mark the first divided frequencies less than the smaller frequency threshold value as fourth divided frequencies.

[0037] 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, then stop; after stopping, obtain the maximum value of the first divided interval corresponding to the rightmost first divided frequency, and mark it as a target threshold value.

[0038] 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: Step S501, obtain a part of the signal fitting function whose ordinate is greater than the abnormal fluctuation threshold value, and mark it as a defective part waveform; Step S502, obtain an endpoint of the defective part waveform, and mark it as a starting endpoint; mark the other endpoint of the defective part waveform as an ending endpoint; Step S503, draw a fifth number of coordinate points equally spaced on the defective part waveform between the starting endpoint and the ending endpoint, and mark them as waveform coordinate points; Step S504, connect adjacent waveform coordinate points by a real-time waveform amplitude value to obtain a line segment, and mark it as a waveform line segment; Step S505, the slope of the waveform segment is obtained, and is marked as a waveform slope; Step S506, the positive and negative cases of the waveform slope are obtained in sequence along the waveform of the defect part from the starting endpoint, and the count is increased by one when the positive and negative cases of the waveform slope change. The total sum of the count from the starting endpoint to the ending endpoint is marked as a real-time detection frequency.

[0039] Step S6, an abnormal frequency threshold is obtained based on the second number of damaged metal wire ropes; step S6 includes the following sub-steps: Step S601, the real-time detection frequency at the second number of damaged metal wire ropes is obtained, and is marked as a historical detection frequency; Step S602, a target threshold is obtained by taking the historical detection frequency as a target value, and is marked as an abnormal frequency threshold.

[0040] Step S7, damage judgment is performed on the metal wire rope based on the real-time detection frequency and the abnormal frequency threshold; step S7 includes the following sub-steps: Step S701, if no real-time waveform amplitude value appears, it indicates that the metal wire rope is undamaged; Step S702, if a real-time waveform amplitude value appears, it is judged whether the real-time detection frequency is less than or equal to the abnormal frequency threshold. If yes, the metal wire rope is damaged. If no, the metal wire rope is interfered.

[0041] 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

[0042] 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 exemplary, for example, the division of the units is only a logical function division, and there can be another division 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 mutual couplings or direct couplings or communication connections between different units, or the among different units, can be indirect couplings or communication connections through some interfaces, devices or units, and can be in 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 a 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.

2. The method of claim 1, wherein the metal wire rope is a steel wire rope. The method for obtaining a 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: Marking the position where the detection of the metal wire rope starts as a starting position, and marking the length from the starting position as a detection position; 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 the coordinate system as a signal coordinate system; Obtaining a signal wave by drawing the data collected by the Hall element in the signal coordinate system, and marking the signal wave as a real-time detection signal wave.

3. The method of claim 2, wherein the metal wire rope is a steel wire rope. The method for obtaining a 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, with a first distance as an interval, and in the positive direction of the X-axis of the signal coordinate system; Dividing the signal coordinate system into N equal spaces by the interval straight lines, and marking the spaces as divided spaces; In each divided space, obtaining the minimum value and the maximum value of the abscissa of the real-time detection signal wave, and marking the minimum value and the maximum value as a first abscissa value and a second abscissa value respectively; Obtaining the minimum value and the maximum value of the ordinate of the real-time detection signal wave, and marking the minimum value and the maximum value as a first ordinate value and a second ordinate value respectively; Marking a coordinate point with the abscissa being the first abscissa value and the ordinate being the first ordinate value as a first coordinate point, marking a coordinate point with the abscissa being the second abscissa value and the ordinate being the first ordinate value as a second coordinate point, marking a coordinate point with the abscissa being the second abscissa value and the ordinate being the second ordinate value as a third coordinate point, and marking a coordinate point with the abscissa being the first abscissa value and the ordinate being the second ordinate value as a fourth coordinate point; Connecting the first coordinate point and the second coordinate point to obtain a straight line, and marking the straight line as a first line segment; connecting the second coordinate point and the third coordinate point to obtain a straight line, and marking the straight line as a second line segment; Connecting the third coordinate point and the fourth coordinate point to obtain a straight line, and marking the straight line as a third line segment; connecting the fourth coordinate point and the first coordinate point to obtain a straight line, and marking the straight line as a fourth line segment; Obtaining a rectangle formed by the first line segment, the second line segment, the third line segment, and the fourth line segment, and marking the rectangle as a division rectangle; Obtaining the midpoint of the division rectangle, and marking the midpoint as a waveform reference point.

4. The method of claim 3, wherein the metal wire rope is a steel wire rope. The method for obtaining a signal fitting function based on the waveform reference point comprises the following sub-steps: Obtaining the waveform reference points of all the divided spaces; Performing function fitting on all the waveform reference points to obtain a function, and marking the function as a signal fitting function.

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

6. The method of claim 5, wherein the metal wire rope is a steel wire rope. The threshold value acquisition method comprises: Obtain the range of target values, and evenly divide the range of target values into fourth number of intervals, and mark them as first divided intervals; Obtain the frequency of target values in each first divided interval, and mark it as first divided frequency; Sort the first divided frequency from left to right according to the minimum value of the corresponding first divided interval from small to large; Obtain the sum of the first divided frequency, and mark it as the second divided frequency; Obtain the value of the second divided frequency by the fourth number, and mark it as the third divided frequency; Set a smaller proportion value; obtain the product of the smaller proportion value and the third divided frequency to obtain the value, and mark it as the smaller frequency threshold value; Mark the first divided frequency less than the smaller frequency threshold value as the fourth divided frequency; Determine whether the rightmost first divided frequency is the fourth divided frequency, if so, delete the rightmost fourth divided frequency, continue to delete the fourth divided frequency to the left, and stop until the rightmost first divided frequency is not the fourth divided frequency; After stopping, obtain the maximum value of the first divided interval corresponding to the rightmost first divided frequency, and mark it as the target threshold value.

7. The method of claim 6, wherein the metal wire rope is a steel wire rope. Based on the signal fitting function and the abnormal fluctuation threshold value, the real-time detection frequency is obtained, which comprises the following sub-steps: Obtain the part of the signal fitting function whose ordinate is greater than the abnormal fluctuation threshold value, and mark it as the defect part waveform; Obtain one end point of the defect part waveform, and mark it as the starting end point; Mark the other end point of the defect part waveform as the ending end point; Draw fifth number of coordinate points equally spaced on the defect part waveform between the starting end point and the ending end point, and mark them as waveform coordinate points; Connect adjacent waveform coordinate points to obtain a line segment, and mark it as a waveform line segment; Obtain the slope of the waveform line segment, and mark it as the waveform slope; Start from the starting end point along the defect part waveform to obtain the positive and negative situation of the waveform slope in turn, and when the positive and negative situation of the waveform slope changes, count once. The total sum of the count between the starting end point and the ending end point is marked as the real-time detection frequency.

8. The method of claim 7, wherein the metal wire rope is a steel wire rope. Based on the second number of metal wire ropes containing damage, the abnormal frequency threshold value is obtained, which comprises the following sub-steps: Obtain the real-time detection frequency at the second number of metal wire ropes containing damage, and mark it as the historical detection frequency; Obtain the target threshold value by taking the historical detection frequency as the target value, and mark it as the abnormal frequency threshold value.

9. The method of claim 8, wherein the metal wire rope is a steel wire rope. Based on the real-time detection frequency and the abnormal frequency threshold value, the damage of the metal wire rope is judged, which comprises 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, judge whether the real-time detection frequency is less than or equal to the abnormal frequency threshold value, if so, the metal wire rope is damaged, if not, the metal wire rope appears interference judgment condition.

10. A metal wire rope nondestructive inspection system for implementing the metal wire rope nondestructive inspection method according to any one of claims 1 to 9, characterized by, It comprises 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 frequency threshold value acquisition module and a damage 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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