An investigation of four experimental and two conventional 75-millimeter-bore (size 215) cylindrical-roller bearings was conducted over a range of DN values (product of bearing bore in mm and shaft speed in rpm) from 300,000 to 2,300,000, radial loads from 7 to 1613 pounds, and oil flows from 2 to 8 pounds per minute with a single-jet circulatory oil feed. The four experimental bearings were equipped with outer-race-riding cages and inner-race-guided rollers. One conventional bearing was equipped with an outer-race-riding cage and outer-race-guided rollers, while the second conventional bearings was equipped with an inner-race-riding cage and inner-race-guided rollers. Each of the six test bearings was equipped with a different design cage made of nodular iron.

A 118-millimeter-bore roller bearing was studied parametrically at speeds from 10,000 to 25,500 rpm. The bearing had a round outer ring (not preloaded), and provisions were made for lubrication and cooling through the inner ring. In some tests the outer ring was also cooled. The bearing ran successfully at 300,00 DN with very small evidence of cage slip. Load, which was varied from 2200 to 8900 newtons (500 to 2000 lb), had no effect on bearing temperature or cage slip over the speed range tested. Bearing temperature varied inversely with cage slip for all test conditions. Cooling the outer ring decreased its temperature but increased the inner-ring temperature. Heat rejected to the lubricant (power loss within the bearing) increased with both shaft speed and total oil flow rate to the inner ring. Schuller, F. T. Glenn Research Center NASA-TP-1413, E-9657 RTOP 505-04...