Numerical Simulation Of The Residual Stress In The Wind Power Bearing’s Heat Treatment Process

The rapid development of wind power industry drived the progress of related bearings industry.The quality of domestic wind power bearings ha s been greatly improved in recent years, but compared with foreign advanced level, there is still a gap in terms of carrying capacity, life and reliability, materials and material handling. The yaw bearing as the large heavy-duty bearing are key components of wind power equipment and they are used in hostile conditions.If the working conditions of the artifacts is worse, the requirement of bearing materials and heat treatment process is also higher. Heat treatment is in the back of the material processing process,and it plays an important role in improving the performance and quality of the parts. Under the condition of the same material, if a better heat treatment process was selected,the reasonable stress distribution could be produced, the uneven deformation could be decreased and the service life could be prolongedThis paper took four-point-contact ball yaw bearing as research object at first, and established proper finite element model using the finite element analysis software Deform.Then simulated the temperature field, the organization field and stress field of the bearing’s outer ring in different heat treatment process.This paper Contrsted and analyzed the change of workpiece’s temperature field in the different heat treatment process and got the cooling curve of the feature points under different cooling patterns. The organization transformation within the workpiece in the process of heat treatment was analyzed.The distribution of the artifact organization composition on cross section was got.Considering the influence of organizational stress, this paper analyzed the change of the instantaneous stress in the process of heat treatment.Then analyzed the possibility of whether the instantaneous stress was oversize, and got the distribution of residual stress field after quenching.Then,the heat treatment experiment of small specimen of 42 Cr Mo was made. The cooling curve of two cooling way include oil quenching and air cooling were tested. Comparing and analyzing the results of numerical simulation and the results of experiments to validate the finite element model, and prove the reliability of the model.This numerical model has a important practice instruction significance to study and analyze any time and any position’s temperature, the microstructure and the stress change situation of the yaw bearing’s outer ring. This numerical model analyzed the bearing’s harden level depth further, forecasted microstructure and performance of the product and analyzed the final distribution of residual stress.It also provided an effective theory basis for making a reasonable heat treatment process of the yaw bearing.