Effect of Preload on the Vibrations of EHL Angular Contact Ball Bearings: Theoretical and Experimental Results

Abstract

The vibrations of a shaft in rotary mechanical systems supported by angular contact ball bearings are investigated theoretically and experimentally for various preloads in this paper. In the theoretical part of the study, a dynamic bearing model is presented, a rigid shaft supported by EHL angular contact bearing has been modelled as 5 DoF. Non-linear equations of motion are solved numerically by the Runge–Kutta method. In the second part of the study, an experimental setup that enables performing different operating cases has been designed to validate the theoretical results. Theoretical and experimental data are investigated and compared in both time and frequency domains and the results are compared. It is observed from both the theoretical and experimental studies that preload has a significant effect on the vibration behaviour. Results show that the increase in preload reduces the amplitude of the variable compliance frequencies of bearing, the natural frequency of system is shifted to a higher value, and using signal processing with an envelope spectrum gives better results in spectral analysis; small deviations occur between the theoretical and the experimental data due to modulation and noise from machine elements such as gear, motor, misalignment, waviness, etc. Therefore, the presented dynamic bearing model can be used with a reasonable accuracy to examine effect of preload on the vibration of shaft-bearing system.

Dynamic characteristics of asymmetrically supported cylindrical roller bearing–rotor coupled system considering variable compliance vibration

“…When the rotor is supported asymmetrically, only one side of the bearing generates excitation energy, while under symmetrical support, the bearings on both sides generate VC excitation energy at the same speed. In the coupled model, the increase in radial load and clearance exacerbates VC vibration, while rotor imbalance has a smaller impact on VC vibration. The results are consistent with the literature, 13–15 verifying the rationality of the model.…”

“…In the coupled model, the increase in radial load and clearance exacerbates VC vibration, while rotor imbalance has a smaller impact on VC vibration. The results are consistent with the literature, 13–15 verifying the rationality of the model.…”

“…The results show that sufficient preload or interference fit will expand the loading region and reduce the vibration caused by bearings. Bal et al 13 established a 5-DOF angular contact-bearing model and studied and compared theoretical and experimental data in the time and frequency domains. The results indicate that the increase in preload reduces the amplitude of the VC frequency of the bearing.…”

Digital twin based condition monitoring approach for rolling bearings

“…When the bearing is in the healthy stage, H d = 0. When the bearing is in the failure stage, unlike in [19,24,25] which regarded the failure shape as a rectangular pit, the contact deformation between the rolling element and the defect edge is ignored. In this study, a fault profile as shown in figure 2 is established to maximize the actual situation of bearing failure.…”

“…In the model, each ball has six degrees of freedom (DOFs), meaning that the three-dimensional motion of balls is considered. Bal [19] presented a multiple-DOF angular contact bearing dynamic model to examine effect of preload on the vibration of shaftbearing system. Qin et al [20] developed a novel dynamic model for a faulty rolling bearing, in which the DOFs of all movable components are considered.…”