Study and Optimization of Three-Dimensional Free Bending Forming Law for Metal Hollow Members
Yang Ao *
School of Mechanical Engineering, North China University of Water, Zhengzhou, China.
*Author to whom correspondence should be addressed.
Abstract
In order to study the three-dimensional free bending of metal pipe forming law, to improve the three-dimensional free bending process of metal pipe forming quality, φ12mm × 1mm TP2 copper pipe as the object of study, through the related blank and material properties on the pipe bending and forming the influence of the law found that the smaller the pipe bending radius, the more significant the impact of the wall thickness on the bending radius of the pipe, pipe molding quality decreases with the increase in the wall thickness. The pipe bending radius size is determined by the material modulus of elasticity, yield strength, pipe hardening index and strength factor and other parameters together. The maximum ellipticity of the pipe is related to the material strength, and the wall thickness variation of the pipe is affected by the hardening index n. Orthogonal tests are designed and simulated for five groups of process parameters to obtain the optimum value of each group of parameters and the importance of the five groups of parameters on the pipe forming quality. TP2 copper pipe free bending test, the test results and the simulation results of the bending angle and bending radius of the numerical deviation is less than 5%, the maximum wall thickness reduction rate and the maximum elliptic rate of the pipe deviation value is less than 2%, it can be seen that the finite element simulation can provide a reliable basis for the actual forming test, the optimization results of the improvement of the quality of tube molding and the improvement of the molding mechanism of the test equipment is of great importance in guiding significance.
Keywords: Metal pipes, free-bending, molding law, process optimization