Research On Crankshaft Parametric Finite Element Analysis System And Design Theory Of Key Parameters In Crankshaft Rolling Process

Aiming at problems about the analysis of crankshaft strength and its strengthening by rolling process, a finite element analysis (FEA) system of parametric 3D crankshaft model is developed and the design theory of key parameters for its rolling process is established.Based on the summarization and improvement of past researches, research on standardization of crankshaft finite element model oriented to improve efficiency, precision and reliability of analysis is carried on. The universal crankshaft FEA system which can parameterize structural dimensions, material properties and size of loadings is developed.Based on the researches on friction transmission between arc-contact rotators, the optimum design model of kinematic and structural parameters in crankshaft fillet rolling is established, and the optimum design is carried out by this model. A new method which can improve the transmission efficiency between arc-contact rotators is put forward. Based on the mechanical model of equivalent cylinders which is built for crankshaft fillet rolling process, the calculation formulae of limited rolling loading considering the influence of structural and material parameters of crankshaft and rolling cutter and layout situation of rolling cutter are deduced. The loading range of crankshaft fillet rolling is studied and the selecting principle of rolling force at different rolling objective is put forward.A new weighted average method of polynomial interpolation which is both simpler in deduction and clearer in physical meaning is suggested in this paper. The shape functions of triangular element and quadrilateral isoparametric element are deduced by this method. Review of numerical method about contact problem is given and the 3D elastic contact finite element program is worked out.By researches on material stress-state in static loading contact problem, the causation of surface work-hardening in rolling process is analyzed. The quantification description on exact definition of surface, subsurface and deep level which appears in local stress problems is presented.Numerical simulation of journal rolling is carried out. The influence on strengthening effect caused by rolling pass and friction coefficient is studied; Theoretical prediction of residual stress in fillet rolling process is carried out. The model and method feasibility is verified by the test result of "Ono rolling specimen."...