Contact Stress Analysis And Fatigue Life Studies Of Wind Power Yaw Bearing

The rapid development of wind power industry drives the progress of related bearingsindustry. The quality of domestic wind power bearings have been greatly improved inrecent years, but compared with foreign advanced level, there is still a gap in terms ofcarrying capacity, life and reliability, materials and material handling. Yaw bearing is akind of large slewing bearing, and it is key component of Wind Turbine Generator. It hasthe characteristics of large size, poor working conditions, complex loads, required longlife and so on. This paper takes four-point-contact ball yaw bearing as research object,analyses its contact stress and fatigue life, in purpose of providing references for thedesign and manufacture of yaw bearing and related slewing bearing.First, using the finite element analysis software Abaqus, this paper analyses thecontact stress of yaw bearing: establishs a static analysis model, solves the stress anddisplacement field distribution under combined load; obtains the law of stress distributionunder the change of initial contact angle, the coefficient of curvature radius, clearance;establishs a partial model with sub-model technique, solves the exact distribution of avariety of stress, analyses the specific location and reason of fatigue failure in raceway; bychanging material properties, obtains the law that how the hardened layer influences thestress distribution.Then, using the fatigue analysis software Fe-safe, which is based on fatiguecumulative damage theory, this paper studies the fatigue life of yaw bearing: confirms themethods of how to select related parameters and their values; obtains the law that how thehardened layer and residual compressive stress influences the life; discusses the methodsof how to produce residual compressive stress. This indicates that raceway hardening is aneffective means to improve the fatigue life of yaw bearing, provides some suggests aboutheat treatment; producing residual compressive stress in raceway is also an effectivepathway, we can try it’s feasibility with the analysis in the paper.