Study On Bearing Failure Of Electric Automobile Air Conditioning Compressor

Electric cars are the development trend of the future automobile industry as wellas one of the key new energy projects supported by the Chinese government. Thecompressor is the heart of the electric car air-conditioner, and its function directlydetermines the energy efficiency of air conditioning, so bearings as the keycomponents of the compressor is particularly important.The bearing of electric carair-conditioner always encounter a variety of problems, bearing premature failure isthe most serious and most worthy of research. The electric automobile air conditionercompressor bearing’s work environment is very complex, so bearing processingresearch is the most effective method. To improve the bearing failure, the main job ofthis paper is the research of electric car air-conditioner compressor bearing, thespecial work as follow:(1)This paper introduce research background and bearing failure theory, analysisof the current research about bearing surfaces processing and existing problems athome and abroad.(2)Conducted a detailed bearing failure problem of electric automobile airconditioner compressor of Guangzhou Jingyi Automobile Air Conditioner Co., a lot oftesting were taken that include: bearing chemical composition testing, the failurebearing touch testing, dimensional accuracy testing, the bearing surface qualityanalysis, the seal lip lubricant cleanliness testing, the hot metallographic analysiscompared with NACHI bearing and the bearing rings residual magnetic testing. Thereasons of bearing failure are detailed analysis to identify the initial improvement thatis bearings optimize design and the bearing ring surface strengthening and polishing.(3)For the problem of bearing failure, the optimal design of the bearing is themain duty including: the key parameters, the dust seal lip, cage and ball selection.Optimal design can increase the bearing run effect and delay the bearing to failure.(4)Strengthening and polishing process can strength the bearing raceway surfaceand enhance the bearing surface yield capacity. Surface residual stress state isshowing a compressive stress state. With strong processing times continue to increase, the bearing raceway surface is no longer obvious to strengthen and gradually reachedsaturation. This way can solve vibration and noise problems by the bearings of theelectric car air conditioner, and bearing failures.(5)Consider bearing design standards and the requirements of the durability testto determine the test conditions as bearing load, temperature, speed. At the same timeanalysis the data calculated and make a conclusion for the testing. The analysis resultsshow that the strengthening and polishing processing can improve the reliability andservice life of the bearing, significantly prolonged the time of bearing failure.