The Wire Rope Fault Detection And Experiment Analysis

As a key part of hoist, transportation and bearing equipment, the wire rope iswidely used in a lot of engineering fields, and the security is one of the mostsignificant aspects during its using. There will be scratch, tear, corrosion, wear orfatigue for various reasons. To ensure safety, the performance of the wire rope needsregularly detection and estimation.The topic researches the principle of magnetic flux leakage testing for thestructural characteristics of the wire rope. And other wire rope testing methods aredescribed. The magnetic flux leakage inspection is established on the basis of aferromagnetic material of high magnetic permeability characteristics. By measuringthe leakage magnetic field of the work piece surface, it will determine the defectinformation. Nowadays this technology is mature with low cost, and the test resultsare stability. So it can be applied to more complex work environment.Based on the principle of magnetic flux leakage testing theory, the failuredetection experiment platform of wire ropes is built.Wire rope testing platform based on the safety of the indoor laboratory testing,finite element simulation and verification. Considering the safety of the experiment inthe laboratory, the experiment platform has the finite element simulation andverification. It has the brief introduction to the characteristics of the data acquisitioncard Advantech PCI-1710U. Based on virtual instrument, the detection softwareplatform of the wire rope is prepared. It implements the detection data collection andpreservation.A series of wire ropes with different faults were produced, including the brokenwires, wear, corrosion and so on. In order to improve the accuracy of signal detectionanalysis and the reliability of detection, this thesis has got abundant experimentalsignals of wire rope failures. In this paper, the traditional filter and wavelet transformare used in fault signal de-noising and analysis. It summarizes the shortcomings oftraditional filtering and the advantages of wavelet analysis.The wavelet transform is different from the traditional signal analysis methodbased on Fourier transform, and the key of wavelet de-noising is the choice of thewavelet threshold. First, the singular points (called "outliers" signal, too) should beremoved; and then the wavelet transform will be used to wire rope signal. Based onwavelet analysis technique, the program for data analysis is written by calling Matlabin LabVIEW.It has obvious effect by using the wavelet analysis. It can not only maintain andhighlight the original signal singularity, but also can accurately extract the signal characteristic of wire ropes through smoothing de-noising. Wavelet analysis has thegood time-frequency property for the treatment of the non-stationary signal.Wire rope will result in the presence of a fault detection signal kinds oflow-frequency energy. Wavelet packet energy spectrum analysis can be effectivejudgment on the degree of damage of the wire rope failure, and it has a certainpractical significance.In order to make the data acquisition and processing done by a testing system, aninterface for wire ropes NDT is written based on LabVIEW2011. It includes dataacquisition, reading and analysis. It can record and analyze data, form experimentalreport and other functions.