Analyzing characteristics of high-speed spindle bearing under constant preload

Abstract

Bearings play an important role in a high-speed spindle. Its characteristics are often influenced by speed and thermal effects. This paper presents an approach that combines an inverse method with a high-speed ball bearing model to determine the characteristics of a high-speed spindle bearing under constant preload in actual working conditions. With temperature distribution in the entire spindle obtained by the experimental inverse heat transfer model from the authors’ previous results, the change in bearing parameters is then calculated and subsequently replaced in the bearing model to analyze the change in bearing characteristics. As a result, thermal effects on a bearing’s dynamic contact angles, contact forces, contact stress, stiffness, and lubricant film thickness are presented. Moreover, analysis results indicate that a bearing’s stiffness and lubricant film thickness nonlinearly vary with the increase in speed, and the thermal effect significantly affects the lubricant film thickness. The results presented herein may be applied to develop a dynamic model for a high-speed spindle using a constant preload and provide useful information to avoid failure in lubrication.

Research Development of Preload Technology on Angular Contact Ball Bearing of High Speed Spindle: A Review

“…As shown in Fig. 6 [39], when rotation speed reaches 10,000 r/min, contact stress of inner ring ( Fig. 6a) is 958.2 N/mm while the outer ring ( Fig.…”

“…The critical speed increase along with the preload rise, while the spindle vibration has a contrary trend, however the decrease tends to slowly when the preload reaches a certain extent [117,118]. Ngo [39] studied the spindle properties in terms of preload from the perspective of oil film thickness variation. Matsubara [119] analyzed the interactions among stiffness, temperature rise and natural frequency of HSS by non-contact loading method, indicated the natural frequency increased with temperature rise and then decreased after temperature reached stable.…”

“…Preload directly affects the contact stress between bearings ring and balls, but Pruvot [22] showed the bearing temperature rise was not positively correlated with the contact stress, which means the temperature was not high when the bearing was unstable under excessive contact stress, and vice versa. Ngo [39] found the contact angle and contact force only slightly changed under thermal effect if the bearing was preloaded by constant pressure, which might attribute to the contact angle and force were directly determined by the preload and bearing design parameters that can hardly altered by thermal effect. Therefore, it can be inferred that the thermal effect is ignorable when analyzing the contact angle and contact force, and thermal expansion has tiny effect on constant pressure preload.…”

One-dimensional model for axial thermal error in a micro high-speed spindle

“…To carry out the deformation of bearing, solving a quasi-static model for high speed ball bearing must be performed. Based on the Matlab code developed by Ngo et al., 29 the quasi-static of present bearing is worked out to obtain speed-dependent δa for several preloads as displayed in Figure 12. It is observed that value of δa nonlinearly increases with increasing the spindle speed.…”

Stiffness characteristics of angular contact ball bearing considering thermal - mechanical coupling

“…Tan et al [18] proposed an alternative assisted differential evolution method to obtain more accurate convective heat transfer coefficients in finite element thermal analysis of spindles. Ngo et al [19] obtained the spindle temperature distribution using an experimental inverse heat transfer model and determined changes in bearing characteristics by replacing varying parameters in the model. Zhou [20] et al introduced a distributed measurement method based on fiber Bragg grating for multi-point measurement of inner and outer ring temperatures in bearings to study their thermal behavior and distribution patterns.…”