Static stiffness of three-row cylindrical roller bearing for rotary table

To improve static and dynamic performances of rotary table, the effects of configurations, assembling technology and external load on the static stiffness of a three-row cylindrical roller bearing for rotary table are investigated. A theoretical model of static stiffness of three-row cylindrical bearing for rotary table is proposed considering the clearance, bolt preloads, and reactions of axial and radial rollers with external load. The contacts between the axial rollers and the outer ring are treated as ideal plane contact. And the actual contact forces and their distribution along the axial of radial rollers are obtained by Boussinesq's relationship between force and deformation, the static stiffness in five directions is then sought out by solving the static equivalent equations. It is shown that the maximum error between experimental and theoretical results of natural frequency of the rotary table is less than 3.0%, thus the theoretical model is verified. The reactions between loads acting on the axial rollers and radial rollers are negligible. The bolt preloads, radial clearance and external load exert obvious effects on the static stiffness of rotary table bearing, and the effect of external load decreases with the increasing preloads of bolts and radial clearance.