The Magnetic Drum (TM for its acronym in Spanish) replaces the movable drum of the belt and it separates the iron metals from any other inert bulk product. The processed material falls by gravity to reach the end of the belt, but the iron metals mixed are retained by the drum, falling separately from the rest of the material already debugged once the magnetic force of the drum stopped operating.
The Rotary Envelop Magnetic Drum (TER) is used in the event of continuous production with bulk material, where there is no conveyor belt. It consists of a drum where there are permanent magnets only in half of the total diameter, and the outer envelope, with ribs on it, is the one that rotates, making the material to be debugged fall by gravity and the retained iron metals until they fall through a different duct from the rest of the material.