Numerical Analysis Of The Contact Problem In High Speed Angular Contact Ball Bearings

As an important supporting part of high speed rotating mechanical equipment,the bearing plays an important role in the performance of the bearing device.In the bearing operation,it’s accompanied by friction and contact between balls and rings,the contact friction leads to the loss of energy consumption,and it sometime witnesses the extreme stress in the micro contact which often leads to wear and surface micro cracks,so it’s necessary to study the bearing contact problems.In this paper,based on the bearing dynamic theory and Elastohydrodynamic lubrication theory,the oil film stiffness equation and the equivalent contact stiffness are obtained.Taking the 7008 A bearing as an example,the contact problem of the high speed angular contact ball bearing is analyzed and studied in detail considering the effect of Elastohydrodynamic lubrication.The contact stress,strain and temperature of the high speed angular contact ball bearing under different working conditions are analyzed considering the effect of Elastohydrodynamic lubrication.The results show that,the bearing contact stress,strain and contact temperature increases with the increase of load and speed;affected by centrifugal force,the contact stress and strain of the outer ring are greater than that of the inner;affected by poor cooling conditions,contact temperature is higher in inner ring than in outer ring;considering Elastohydrodynamic lubrication bearing’s contact stress,strain and temperature increase with the increase of speed and load,the effect of Elastohydrodynamic lubrication on bearing contact stress,strain and temperature become more significant.The influence of different working conditions on the contact problem of high speed angular contact ball bearings is discussed.It can be concluded that the contact properties of the ceramic ball bearing is better than that of the steel ball bearing under different loads and speeds;when the bearing temperature is over 200℃,the friction coefficient of the bearing is raised sharply,the bearing contact stress will increase rapidly when bearing friction coefficient is higher than 0.02;bearing maximum contact stress and strain are increased with the oil viscosity;when lubricating oil viscosity is near 0.01Pa·s the friction coefficient is the smallest.The results show that elastohydrodynamic lubrication conditions and the friction coefficient have an important influence on the stress and strain under different working conditions,the research results have a certain reference value for the improvement and optimization design of high speed angular contact ball bearings.