Fatigue Life Prediction of Rolling Bearings Based on Modified SWT Mean Stress Correction

Aodi Yu,He Li,Yan-Feng Li,Hong-Zhong Huang,Ying Zeng

doi:10.1186/s10033-021-00625-9

Abstract

The existing engineering empirical life analysis models are not capable of considering the constitutive behavior of materials under contact loads; as a consequence, these methods may not be accurate to predict fatigue lives of rolling bearings. In addition, the contact stress of bearing in operation is cyclically pulsating, it also means that the bearing undergo non-symmetrical fatigue loadings. Since the mean stress has great effects on fatigue life, in this work, a novel fatigue life prediction model based on the modified SWT mean stress correction is proposed as a basis of which to estimate the fatigue life of rolling bearings, in which, takes sensitivity of materials and mean stress into account. A compensation factor is introduced to overcome the inaccurate predictions resulted from the Smith, Watson, and Topper (SWT) model that considers the mean stress effect and sensitivity while assuming the sensitivity coefficient of all materials to be 0.5. Moreover, the validation of the model is finalized by several practical experimental data and the comparison to the conventional SWT model. The results show the better performance of the proposed model, especially in the accuracy than the existing SWT model. This research will shed light on a new direction for predicting the fatigue life of rolling bearings.

Highlights

Complicated rotational machines and systems like machine tools [1, 2], wind turbines [3, 4], and robots [5, 6] having emerged during the last several decades
Today’s complicated rotational machines and systems require rolling bearings work in harsh conditions, such as heavy load, high speed and high temperature, which brings about challenges to several crucial performances of rolling bearings like reliability and service life
In this paper, we attempt to consider the sensitivity of different materials to mean stress and propose a modified life prediction model based on the SWT correction

Summary

Introduction

Complicated rotational machines and systems like machine tools [1, 2], wind turbines [3, 4], and robots [5, 6] having emerged during the last several decades. Quagliato et al [19] predicted the life of roller bearings by accelerated testing, and finite element (FE) models, was developed for crossed and tapered roller bearings He et al [20, 21] proposed a method to test the accelerated fatigue life using a small sample test, which provides an experimental reference for bearing design, and provides the foundation for studies of the fatigue failure mechanisms of raceways. The influence of mean stress needs to be considered when predicting the contact fatigue life of rolling bearings. In this paper, we attempt to consider the sensitivity of different materials to mean stress and propose a modified life prediction model based on the SWT correction.

Modified Fatigue Life Prediction Model Based on Mean Stress Correction

Fatigue Life Prediction of Rolling Bearings Based on the Proposed Model

Validation of Modified Fatigue Life Prediction Model Based on SWT Correction

Life Prediction of the Proposed Model for Rolling Bearings

Conclusions