Research On Material And Mechanical Property Of Slewing Bearing

There are many types of domestic slewing bearings produced atpresent, but products with high technology are not too many, and thequality is not perfect, which needs further research and optimization.This paper studies the material and mechanical properties of slewingring, the main contents and results are as follows:(1) Various types of the structure and characteristics of slewingbearings are investigated. Based on the classic Hertz theory of elasticity,formulas of stress, strain and the applied load distribution betweenrolling elements and raceway of slewing bearings are derived. Based on1200style of four-point contact with a single-row ball slewing bearingcommonly used in slewing ring industry, the influence of the R/r ratio,the radius of rolling ball and contact angle on the contact stress betweenball and raceway is comparatively studied by theoretical calculation. Itis concluded that structure parameters of slewing bearing reasonablyselected can greatly reduce the contact stress.(2) Based on contact problems of ANSYS analysis methods, thethree-dimensional model of the slewing bearing is created by CATIAsoftware. The model is meshed by HyperWorks software. Contact stressbetween ball and raceway on external loads is calculated by ANSYSsoftware finally. Compared to theoretical calculation, it is concludedthat the values of the two methods are very close with error less than10%, and the correctness of theoretical calculations and finite elementanalysis is verified.(3) Material and its selection are discussed, and thermal processingand mechanical processing of slewing bearings are studied. It is foundthat the material performance of the slewing bearing is greatly improvedafter heat treatment process by slewing bearing specimen tests. Afterfurther studying of metallographic observations and hardnessmeasurements of test samples, influences of heat treatment onmicrostructure and mechanical properties are discussed, and the importance of preheating treatment and surface hardening is revealed.