The cleaning of bearings is a unique sub-set of the general metal cleaning environment. Bearing cleaning can be relatively straightforward if the application is the preparation of new bearings for distribution and parts simply need to be coated with an approved lubricant. But bearing cleaning becomes far more complicated when companies need to remove production lubricants that have been impregnated in the ball bearings, or if production debris entrapped in the raceways, or if the bearings are being returned for overhaul and maintenance.

Most commonly, contaminates to be removed are machining oils, stamping fluids, drawing oils or burned-on lubricating oils. If the bearings have been returned from the field for rework, the contaminates could also include particulate, dirt, burnt or stressed lubricants, and other foreign matter.

The chosen cleaning fluid should be compatible with all bearing components and leave no residues which could react with lubricants.

Manufacturers who were using nPB to clean bearings should consider: