WIRE-ROPE TEST METHOD, WIRE-ROPE TESTING APPARATUS AND MAGNETIZING HEAD

摘要

A wire rope tester which can detect broken wires, area reductions, or wire contact irregularities. The tester includes two permanent magnetic stacks (32 to 38) which produce axial adjacent and opposed DC magnetic fields which magnetise the rope (46). Broken wires are indicated by flux variations when the flux density is at saturation (j1,j2); area reductions are related to flux variations (j1,j2); also at saturation flux density; and wire contact pattern changes produce detectable eddy current flux variations (k) when the flux density gradient is constant.