Contaminants from 1 to 40 microns in size are common even in full-flow, filtered lubricants and coolants. Larger contaminants nest into areas around bearings, rings, pumps, etc. and damage component surfaces. Smaller contaminants, that cannot be removed by full-flow filters, wear the apparatus by a process called silting.
For many years, partial-flow filtration has been used to supplement full-flow filters to remove larger contaminants and control silting. Harvard Corporation did not invent partial-flow filtration, but we significantly improved it. Our patented, non-channeling seals improve partial-flow filtration by forcing oil through a wound, fiber-filter media so fluids can not bypass the partial-flow filter.
Independent studies conducted by the Center for Hazardous Materials Research at the University of Pittsburgh demonstrated the effectiveness of Harvard Corporation's non-channeling, partial-flow filter. The filter removes virtually all remaining 1 to 40-micron contaminants while also removing the vast majority of silting particles. In addition, the filter absorbs water, antifreeze and other extraneous particles.