Research On Numerical Simulation Of Forming Limit And The Forming Parameters Optimization

Application of thin-walled tube have a huge role in the main production of aviation, shipbuilding, automobile manufacturing, metal structure, mechanical engineering. With the rapid development of all walks of life,it has more and more demand to forming quality of thin wall pipe fittings. Because of that study and control on the forming limit of thin-walled tube bending have became an urgent problem on inquiry and investigation the thin-walled tube bending technology.This paper introduces the research status of thin-walled tube bending forming limit numerical simulation and influence of forming parameters on the tube forming at home and abroad, based on this, have a theoretical research on the forming process of tube processing, use the elastic plastic theory and the theory of mechanics of materials to study on tube forming process in detail, analysis the elastic and plastic deformation process of each point on the cross section and calculate the formula of stress and strain. It is lay the theoretical foundation of study the outer wall thinning, inside wrinkling and section distortion. According to the theory of finite element analysis, determined the material constitutive relation, contacted the boundary condition, deterministic algorithms for solving finite element analysis technology. Through CNC pipe bender experiment prove the validity of the numerical simulation model, then use the numerical Simulation Model analysis the loss of pipe forming limit wrinkling, distortion and forming limit wall thinning rate of forming limit. Finally, get the influencing factor of the forming limit and the change regulation.Finally, in order to improve the quality of pipe, reduce the occurrence of the three forming defects of wrinkling, cross section distortion and thinning of outer wall, the forming parameters were optimized by orthogonal experimental design, data and analysis of variance. The experimental results show that orthogonal test optimization method can improve the quality of pipe forming, which shows that the technology can be adapted to the actual pipe processing.This paper not only carry out the theory and simulation analysis of three kinds of forming limit of thin-walled tube bending, but also optimize the forming parameters on this basis, it has great significance for improving the quality of thin-walled tube bending forming.