Analytical Investigation of Roller Skew and Tilt in a Spherical Roller Bearing

The objective of this investigation was to analytically investigate the performance of a spherical roller bearing (SRB) operating under various loading and speed combinations. In order to achieve the objective, a full six degrees-of-freedom SRB dynamic model was developed. The model was corroborated with results in the open literature. An adaptive slicing method was developed to optimize the accuracy and computational effort of the roller force, skew, and tilt calculations. A comprehensive roller-race contact analysis in terms of slip velocity and contact area was then carried out to identify how bearing load and inner race (IR) speed variations change slip velocity and skew at the roller-race contact. The results from this investigation demonstrate that roller skew increases with IR speed, while the roller tilt remains relatively constant. The IR speed and roller slip velocity correlate well, which causes the traction force to increase and therefore produce greater skew. Skew and tilt angles also increase with applied axial load. However, at a certain load, the skew angle begins to decrease.