Theoretic Analyses And Numerical Simulation Of Three-Roll Pyramid Type Plate Bending Machine Bending Process

Rolling machine is widely used in shipbuilding, boiler, chemical and aviation industries. Commonly the material in bending process always is elastic-plastic material, so springback can not be avoided which makes the final size and precision of the workpiece can not be ensured. Hence the key problem in the bending process is to select proper technical parameters. The traditional technical method from vast experimental data obviously reduces the productive efficiency, increases the cost and weakens competitive power. In order to solve the difficult problem of rolling adjustment and direct the manufacturing, the theory of rolls bending is studied and the laws of forming is concluded in this dissertation.Based on the theoretic and finite element simulation, the paper analyses the bending process profoundly.First, based on the analysis of plane bending theoretic and the former research achievement, the paper uses harden elastic-plastic model in place the ideal elastic-plastic model for plane bending theoretic, builds the relationship between the descent of upper roll and bending radius, offers the basic for simulation and gives an convenient interface by VB.Next, based on the theory basis and finite element software DEFORM-2D, this paper models and simulates the bending process. The results indicate that this method is feasible. And this paper simulates the one-time shaping progress, studies the influence of the structure parameter of the bending machine and the geometrical size of the plane on the bending radius and analyses the reasons.Last, this paper studies and simulates the springback in the bending process. Obtain the stress distribution of the plane in the bending process and in the most serious deformation section, and the stress distribution of the residual stress.