Grease life in shielded/sealed ball bearing   logL= 6.10-4.4010-6dmn-2.50 (Pr / Cr-0.05) - (0.021-1.8010-8dmn) T

where: L : grease life h dm : (D + d) / 2 (D : bearing outside diameter, d : bearing bore diameter) mm n : rotational speed min-1 Pr : dynamic equivalent radial load N Cr : basic dynamic radial load rating N T : operating temperature of bearing

The conditions for applying equation are as follows. When other conditions are applied, Koyo should be consulted. a) Operating temperature of bearing : T Applicable when T120   50 ; b) Value of dmn Applicable when dmn500,000  when dmn125,000 ; dmn=125,000 c) Load condition: Pr / Cr Applicable when Pr/Cr0.2  when Pr/Cr0.05 ; Pr/Cr=0.05