Failure Analysis on Aero-Engine Spindle Ball Bearings

The macrography and hardness test are conducted for the failure bearing,the fracture analysis and metallographic check of the first broken part are carried out,and the energy spectrum analysis of the collected metal chips is done.It is found that the bearing failure has no relationship with material properties;the bearing endures a non-normal force during work.The theoretical analysis is performed to the aero-engine assembly geometric tolerance K11 and K12 which might influence normal operation of the bearing.The results show that bearing deflection after the aero-engine assembly should be the main reason of bearing failure.