Ball Bearing Raceway Curvature || Dynaroll

Inner raceway curvature ratio fi =   Ri Dw Outer raceway curvature ratio fo =   Ro Dw

where: Dw = ball diameter Ri = inner raceway radius Ro = outer raceway radius

f_i, f_o values are typically 0.56 ± 0.03 for small bearings where low torque is a primary requirement. It is not necessarily the same for both inner and outer raceways. Raceway curvature ratio is often referred to as a percentage f x 100%.


The total curvature of a bearing is defined as B = f_i + f_o - 1