Study On The Effect Of Non-uniform Preload Of Bolt And Topology Optimization Of Supporting Structure On The Life Of Slewing Bearing

The slewing bearing is an indispensable part of the large machine with rotating motion,its main function is to connect two relatively rotating components,which are widely used.The slewing bearing is connected to the upper and lower supporting structure through high-strength bolts,so the bolt connection is very important.For different machines and places of use,the supporting structure of the slewing bearing is not the same.Therefore,the bolt connection and supporting structure are the two major external factors of the slewing bearing.This paper is derived from the National Natural Science Foundation funded project,whose name is “Fundamental research on the effect of bolt connection and supporting structure on the life of large-scale slewing bearing(Grant No.51465025)”.Finite element method is used to study the effect of non-uniform preload of bolts and topology optimization of supporting structure on the life of turntable bearings in this paper.Firstly,slewing bearing rolling elements and bolt connections are simplified,the finite element model of slewing bearing test bed with bolt connection is established in this paper.The effect of bolt connection on the contact load and contact angle distribution of the rolling bearing of the slewing bearing was studied.The influence of the preload force of the uniform bolt and five kinds of non-uniform bolt on the contact load and the contact angle distribution of the slewing bearing roller and the relationship between the preload force and the maximum contact load are also analyzed.Secondly,the model is established by using SolidWorks.Using the variable density method,the minimum mass of the supporting seat is the objective function,and the size of the optimized grid and the stress constraints are set in this paper.Topology optimization is carried out in the Optistruct,and then,according to the topological optimization results,the design of the lower support is redesigned,and the model of therotary bearing experiment table is re-established in ANSYS to conduct the finite element analysis.The influence of topology optimization on the mechanical properties of supporting structure and slewing bearing is studied.Finally,the improved Lundberg-Palmgren life calculation method is used to study whether the bolt connection,uniform bolt preload force,non-uniform bolt preload force and topology optimization of the supporting structure on the fatigue life of the slewing bearing in this paper.