Magnetic flux leakage evaluation and signal sensitization for steel wire rope via discrete magnetic-charge volume method and adaptive sensor arrays

Magnetic flux leakage (MFL) is an effective method for the quantitative non-destructive evaluation of steel wire ropes (SWRs). However, it still suffers from a complex MFL field evaluation process and strand-signal interference in the detection signal. Motivated by these limitations, this paper investigates the theoretical basis and signal-sensitisation strategy for MFL signals. A discrete magnetic-charge volume method (DMVM) is proposed for rapid and flexible three-dimensional MFL analysis in SWRs, with emphasis on waveform characteristics and relative spatial distributions. The MFL characteristics of broken wires and strands are examined, with particular emphasis on the center offset effect. Furthermore, an adaptive sensor-array-based sensitisation strategy is developed to suppress strand noise, compensate for center offset, and enhance the amplitude response of defect signals. The experimental results confirm that the proposed DMVM supports efficient SWR defect evaluation and that the sensitisation strategy improves defect-response extraction.