抄録
Recently, the problem of detecting and removing tramp metal pieces in ore is becoming greatlyimportant in the mill operation, because these tramp metal pieces sometimes cause serious damage to orecrushing machineries, resulting in unnecessary expense and loss of time for repair. When the tramp metalpiece is magnetic, it is easily removed from ore by the magnetic separation method applying suspendedmagnet. Even though the tramp metal piece is non-agnetic, it is generally detected by the conventionalindustrial metal detector applying the distortion of A. C. magnetic field. When ore itself is magnetic likea magnetite, the above methods have some difficulties to be used for this purpose. Described in this paperto solve such a problem is a mining metal detector which can detect tramp metal pieces in the magneticore by using the difference of specific resistance between ore and metal.
