Eddy Current Rolls

Product Discussion

Magnetic rolls have been used for decades to separate ferrous from non-magnetic materials. Eddy Current Rolls, in use since about 1970, are used to separate conductive from non-conductive materials thus allowing the separation of aluminum cans, wire, stainless steel and other non-magnetic, but conductive materials.

Eddy current rolls are constructed using very strong permanent magnets in various arrangements to maximize the field around the roller. As the roller quickly rotates the propagated magnetic field generates eddy currents in the adjacent conductive material. These eddy currents generate a magnetic field in opposition to the applied field causing repulsion and affecting separation of the conductive metallic from the non-metallic materials.

These roll designs are effective at separating non-ferrous metallics from plastics, glass, electronic scrap, automobile shredder residue, foundry sand, trash, co-mingled recyclables etc.

Arnold specializes in construction of new and in the rebuilding of old, damaged Eddy Current (and Magnetic Separator) Rolls. This roll has been cleaned and refurbished and is ready for wrapping. Damaged magnets were removed, the rail structure repaired and new magnets fastened in place. This particular structure utilizes a wedge-shaped magnet between two pole magnets creating an extremely strong field with long "throw".

The magnets are assembled in the magnetized condition requiring careful handling and mechanical assistance to maintain positioning during and after assembly.

To work effectively Eddy Current Rolls depend upon a strong magnetic field and fast movement. These rolls spin at many hundreds of revolutions per minute creating large centrifugal forces. Magnets are held in position by a combination of high strength/high temperature adhesive and a Kevlar wrap.

For safety, operators receive special training.

When the rolls are ready for shipment to the customers, large, extra strong crating is utilized. Made entirely of wood and dense foam, the rolls are protected during transit and upon receipt by the customer.