Steel ropes, which are subjected to severe working conditions in hazardous areas such as in mines and on aerial ropeway installations, deteriorate with use. The only really effective technology that is in current use depends on the magnetic properties of steel wire rope. The most widely used method to study the condition of steel ropes is the magnetic non-destructive method. Magnetic non-destructive evaluation allows an increase in the safe and use of steel ropes due to subjective, reliable and documented evaluation of real rope condition and by ensuring timely rope replacement. The electromagnetic non-destructive evaluation process employs (1) fringe fields near the surface of rope to detect local defects such as broken wires, corrosion pitting, local wear and (2) changes in magnetic flux passing through a short length of rope to quantify changes in metallic cross-section. Magnetic method accurately depicts wire rope defects, including those missed by visual inspection. The most effective way in which non-destructive evaluation of rope is currently used is a means of improving the reliability of the initial identification of the location of significant degradation along a rope. Periodic evaluation of rope by electromagnetic method should be carried out since installation of rope. With the combination of nondestructive evaluation and skilled examination, the rope life can normally be extended. Electromagnetic non-destructive process and its emerging role in the cases of mine winders (cage, skip, drive ropes etc.) and aerial ropeways (track and haulage ropes in cable cars, chairlift, ski-lifts etc.) have been discussed.
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