Based on the introduction and analysis of difficulties encountered during technical inspection of the wire rope of a winding mine hoist (WMH) working at high speed, an open-loop permanent magnet magnetizer was used to simulate and analyze the effect of the structural dimensions of this magnetizer on the magnetic leakage field of a defect, and the results of the simulation analysis were initially verified by experiments. Additionally, in order to keep the axial position of the probe in line with the axial position of the wire rope, a rocker arm was proposed to act in coordination with a motor to drive the clutching open and closed probe, thereby creating an on-line nondestructive testing device to float and track the movement of the wire rope in different directions. Finally, the device was applied to testing of WMH wire rope on site to validate the effectiveness and feasibility of the method.

Metallic probe carriers are commonly used in magnetic flux leakage (MFL) inspection to support sensing elements and maintain lift-off, but a conductive carrier located near the sensor can act as an active electromagnetic boundary. This study investigates the carrier-induced waveform reconstruction caused by such a conductive near-field boundary. A theoretical model is developed to describe the induced current, secondary magnetic field, and relaxation-related downstream memory generated when the carrier moves through a non-uniform leakage field. Transient finite-element simulations are used to examine the effects of carrier material, scanning speed, and concave carrier geometry. Compared with the air reference, aluminum and copper carriers produce stage-dependent waveform reconstruction, including valley modification, peak modulation, feature-position shift, and trailing-side extension. The quantitative waveform-deviation indicators increase with increasing speed and are further regulated by carrier geometry. Experimental results based on repeated magnetic response events confirm amplitude suppression, non-zero residual after amplitude matching, response broadening, and enhanced trailing asymmetry. These results demonstrate that the metallic probe carrier is not an electromagnetically transparent holder but an active near-field conductive boundary that should be considered in probe-carrier design and MFL signal interpretation.

Using finite element simulation analysis, different wire rope structures with the same diameter and damage models were created for analyzing the principle of magnetic flux leakage (MFL) wire rope inspection. As a result, different wire rope modelling structures result in different distributions of the internal magnetic field within the wire rope as well as the leakage magnetic field at defects. Therefore, it is important to establish a reliable wire rope topology when studying the leakage magnetic field pattern around wires and defects.