Electromagnetic method of testing the
wire rope is the most widely practiced nondestructive
method of studying the
condition of wire rope under in-situ
conditions. In this method, wire rope is
magnetized using powerful magnets [1, 2].
The magnetic lines of forces travel along the
axis of wire rope. If there is a discontinuity,
the magnetic lines of forces deviate from
their path and there will be a leakage field to
the air. Using suitable sensors, leakage
fields are detected, recorded and analyzed to
identify the type of discontinuity. Fig. 1
shows the schematic layout of the
equipment used in electromagnetic testing.
faults, which includes broken wire, wear,
corrosion, pitting, and inter strand nicking.
Inductive coils are used to detect these
defects. This is detected by the inner coil of
the equipment.
• LMA Sensors: LMA means loss of
metallic area. Hall sensors are used to
measure this parameter. This is detected by
the outer coil (Hall sensor) of the
equipment.
