Research On The Failure Analysis And Improvement Of Grease-lubricated Bearings Used In Aeromotors

The grease-lubricated sealed bearing is a very promising product,it can simplify the design of bearing parts of the host.There is no need to add sealing device and lubrication system for the effective sealing and lubrication.It 's easy to installate and with no pollution,it has reliable performance characteristics of sealing.Therefore,it has been widely used in small and medium sized motors,agricultural machinery,textile machinery,automobile and so on.In the developed countries,more than 50 percent of them have developed into sealed bearings.In China's aviation field,sealed bearings are used in aircraft,aircraft accessory drive and aircraft body part,which are used as both ends of the bearing,supporting the aviation motor,because of the frequent impact,vibration,high temperature,high speed and other harsh conditions.The reliability is low during the probation period,it often occurs fault such as axle,high and low temperature buring,damaging to the distegration.To a certain type of aircraft motor with typical high temperature failure of 62206-2RS bearing as the research object of this paper,detecting the fault analysis,from the macro observation bearing,microscopic observation,metallographic examination,hardness testing grease testing and so on.Analysing bearing structure parameters of the matching conditions by COBRA simulation analysis of quasi static analysis software,getting the ball the diameter and number of curvature coefficient,radial clearance optimization parameters,the calculation of life greatly improved.At the same time,in order to obtain a good lubrication condition,through the test results of 4 kinds of typical aviation grease in the bearing,finding that the filling amount of grease and the load-carring properties of the grease play an important role in raising the temperature of the bearing.By analyzing the result,formulating measures for improvement.At last,the bearing were analyzed by the test and comparison before and after the improvement of experimental,it's proved that the improved measures are effective,the bearing life and reliability is greatly improved,completly eliminating faults and problems.