Finite Element Analysis And Research Of Induction Quenching And Grinding Process Of Camshaft Of The Marine Diesel Engine

As one of the key parts of marine diesel engine,camshaft's working condition which is high velocity and stress distribution are very complex.It's special work environment need it have certain strength,stiffness,toughness and good wear resistance.Its performance is a directly affect to the quality and longevity of diesel engine.Residual stress affects the cracks and extension,so residual stress which is too large is likely to lead to the disqualification of the camshaft.Surface induction quenching and grinding process are important in the process of camshaft of the marine diesel engine,which directly impact on the distribution of the surface residual stress.This article adopts the method of finite element analysis and experiment to analyze the process of induction quenching and grinding of cam,and have the research the rule of the cam surface residual stress under different parameters,laying a foundation for improving the quality of processing of surface for the camshaft.(1)Based on the electromagnetic and heat transfer theory,electromagnetic field and temperature field theory of induction quenching process of cam are analyzed,the model of electromagnetic-thermal coupling mathematical of camshaft is established.Both of transient temperature field of quenching and grinding process is analyzed by the heat transfer between the cam and the cooling fluid.The Prandtl-Reuss theory is used on the residual stress field and set up the cam mathematical model of induction quenching and grinding process.(2)According to the process of characteristics of the camshaft induction heating,the finite element model of cam contour induction heating is established and solved the electromagnetic field,temperature field and the change rule of temperature by electric-magnetic-hot three coupling method,providing the necessary preparation for the cam quenching process.(3)Based on thermal elastic and plastic theory,the finite element model of induction quenching process is established.Design orthogonal experiment table of induction heating parameters,considering austenite phase transformation,and finally achieve the completion of the field,distribution of residual stress field after the quenched.(4)According to the camshaft grinding process characteristics,the finite element model of the grinding temperature field is established,and finally achieve the residualstress distribution rule of cam contour surface by the method of thermal-mechanical coupling analysis.Design the orthogonal experiment of induction quenching and grinding process parameters,looking as two different martensite and matrix material,the completion of residual stress that based on the induction quenching residual stress is studied.Finally the feasible process parameters is presented on the low residual stress goal,to provide reference for solving the problem of crack or delay crack on contour surface of the cam.