NUMERICAL PROCEDURE TO DESIGN A DIE AND STUDY ITS RELATIONSHIP WITH SOME PARAMETERS INFLUENCING ON THE BENDING PROCESS OF SHELLS

Abstract

In this study a numerical procedure was proposed for the design a die bending to study the effect of springback which influences the bending process and its relationship with other parameters such as friction coefficient, bending load, die geometry, sheet thickness, Young modules, and stress level. Using available finite element program code( ANSYS .11) 3- Dimension ax symmetric model of semi conical shells was used to solve problems with material and geometric nonlinearities including large elastic- plastic strains and obeying bilinear isotropic hardening law. The result compared with analytical solution and showed that the best bending variables for producing completely product without failure are found as initial bending force = 12 KN, coefficient of friction = 0.1, the cone angle = 30 deg. So the springback increases inversely with young modulus and is normally compensated for by over bending the part also can bend at elevated temps to minimize springback A high value of stress and strain appears to be a good indicator to assess whether forming operation will be successful or not. The theories results were compared with Numerical solution and showed that a good agreement was compared with old research