The Numerical Simulation And Process Optimization Of Engine Crankshaft Hot Forging

With the development of China's industry and the improvement of people's living standards,people's requirements on automobiles are becoming higher and higher,and the production quality of auto parts is also becoming higher and higher.Crankshaft is the core part of automobile engine,when the engine works,the crankshaft bears the alternating load,has the extremely high request to its strength,the hardness,the wearability and so on performance.However,due to the complex structure of crankshaft,it is difficult to guarantee the forming quality.In this paper,the 06d02 crankshaft is taken as the research object,two forming processes of pre-forging and final forging of crankshaft forming are determined through technological analysis,and the whole process of hot-forging of crankshaft is simulated based on DEFORM software.Through co MParison,it is concluded that the structure of resistance groove and resistance wall for preforging die can effectively solve the problem of filling dissatisfaction of balance block.At the same time,analysis of the crankshaft in the process of forming the largest load,temperature field,velocity field and the distribution of folding,which at the corner of the crankshaft connecting rod of diameter,the diameter of axle prone to fold defects,in the process of the crank arm inside concave shape flow too fast result in forming quality is poor,and forming load is bigger,mold wear.To solve the problem of the crankshaft forging forming defects,the response surface analysis optimize the crankshaft mold flash tank structure,establish a drag groove radius,height of the resistance and the height of the flash bridge as design variables,and using the forming load and mould wear as the target response model,of the optimal combination of die structure parameters as follows:Resistance groove radius for 9 mm,resistance wall height is 0.65 mm and the height of the flash bridge C6.5 mm,the maximum forming load at this time is3920 T,reduce 7.9% than before optimization and after optimization of maximum foldingAngle is 318 °,distribution in the region of the flash,has no effect on the forming quality of crankshaft,and the crankshaft of the ontology folding Angle 250 °,folding to effectively solve the problem.In addition,the response surface method(RSM)and particle swarm optimization(pso)were used to optimize the process parameters of crankshaft forging.The optimal combination scheme of process parameters was obtained: the pressing speed was100mm/s,the blank preheating temperature was 1200?,and the mold temperature was240?.At this time,the maximum forming load was 4210 T,and the mold wear R2 was0.0178 mm.The mold wear was reduced to 10.1% co MPared with the scheme before optimization,so the optimized combination of process parameters could effectively reduce the mold wear.the optimization of the mold and the process parameters of the optimized scheme for the actual production verification,the actual production verification shows that the optimized scheme,can effectively avoid the crankshaft folding defects,reduce the forming load and mold wear,at the same time the study of the same kind of crankshaft hot forging production to provide some guidance.