The Technical Study And Numerical Simulation On Tension Straightening Technology For Shaft Parts

Nowadays, industries from machinery、transportation and automobile are under rapid development. With the consistently improvements on production scale and technical merit, the quality and precision requirements on some essential parts are requested much stricter than before. As one of the most important parts for mechanical device and automobile, shaft parts may be bended due to the manufacturing defects and long-time use, which would affect the production efficiency and safety performance. In this paper, based on the traditional pressure straightening technology, the tension straightening technology is put forward, which could be applied in the hot or cold straightening process for some shaft parts with larger diameter.Based on theoretical analysis and finite element numerical simulation, the main works of this paper are as followed:40Cr Ni Mo was used as the research material, whose flow stress curve was received by heat compression experiments. And in accordance with the experiments data, the Z parameter model of peak stress in high temperature was established.Based on the press straightening technology theory, the mechanical model of tension straightening technology was established. Theoretical analysis were deduced for the geometrical relationship 、 elastic deformation and elastic-plastic deformation in this technology,and the numerical relationship between pressure and tension was provided.By the application of finite element analysis software ABAQUS, the mechanical model of tension straightening technology was verified, and the straightening laws of this technology were explored. The impacts of tension amount and part’s size on the straightening results were discussed, and the optimal value ranges of tension were got by numerical simulation.Through numerical simulation, the tension straightening technology was adopted to the heat straightening of a car axle. The stress、bending springback and straightness of the straightened car axle were discussed.The research result shows that: the tension straightening technology could reduce bending recovery and improve straightening precision effectively, which has a certain theory value and a broad prospect for application.