Study On Optimization Of Precision Die Forging Process Of Automobile Crankshaft

The crankshaft of automobile is one typical die forging part with complex structure, which is usually formed by a complicated process under the high forming requirement. In recent years, due to the demand of high performance of automobile, such as heavy load, high speed, high reliability, etc., the requirement of crankshaft's performance has also been uprated greatly. Therefore, it is of great importance to optimize the forging process to improve the mechanical performance of crankshaft.The forging process of crankshaft is very complicated, the feasibility, stability, quality of forming (including fulfilling, wrinkle and structure defect), material yield and mould lifetime, etc. are all the key factors that should be considered with emphasis during the forging process decision.This paper briefly introduces the precision die forging process of crankshaft and the research status of the forging development home and abroad, choosing the QZ3 automobile crankshaft as a typical forging part, introduces the application of CAD/ CAE technology in the optimization of precision die forging for automobile crankshaft. By the experience design with three-dimensional modeling software UG and the numerical simulation with Deform 3D, the influence on the metal flow, mould filling, stress and strain distribution of forging part, die load, and material yield from the parameters of web and resistance wall are analyzed. Through the simulation analysis, the structure and size of web, the parameters of resistance wall, and the billet size are optimized, which realize the target that improve the die structure, get rid of the forming defects and increase the material yield. In the end, based on the comparison between simulation and examination, the successful experience of this research is concluded.The precision die forging of crankshaft, finite element theory, numerical simulation and CAD technology of mould are combined in this paper, and the research result achieves the following purpose: shortening the cycle for product development, reducing the material cost, and improving the die life, etc., which could be used to guide producing directly and provide a theoretical base and technological support for producing other similar crankshafts.