Selective Plating for Electric Motors and Generators

Electric Motors and Generators

Plating bearing surfaces to size

The SIFCO Process® is very effective for repairing electrical generating equipment.

The primary application areas are the bearing housing (end bell) and the rotor journal.

Applications for the SIFCO Process®

End bells, which house the bearings that support both ends of the motor shaft, often suffer from fretting corrosion during operation. The SIFCO Process® is used to plate the bores to size with copper, tin, or nickel. Machining the bores, prior to plating, is usually only necessary to re-establish concentricity.

Plating a worn bearing housing can take less time and be more efficient than alternative methods such as sleeving or thermal spray processes.

DC motors and generator slip rings develop copper oxide films which reduce electrical conductivity and cause arcing and pitting especially during locked motor start-up. Excessive damage occurs in highly corrosive environments, such as in the bleaching areas of pulp and paper plants. Plating 2.5µ (0.0001 in.) of rhodium and then 1.3µ (0.00005 in.) of gold onto the refinished commutator extends maintenance intervals and service life.