The establishment of roll bending finite element model is the first condition for numerical simulation of roll bending process. The accuracy of the simulation results is directly influenced by the established model and the actual situation. The roll bending process can be regarded as a plane strain process when the width of the sheet is far greater than the thickness of the rolling plate. In this way, a three-dimensional problem can be transformed into a two-dimensional problem, thus reducing the amount of calculation. There are two ways of modeling : one is imported from the outside and the other is modeled directly. In this paper, second methods are used in the modeling.
Because in the simulation when the roller to rotate around the center, and the center is the absolute coordinate system in a given coordinate system, from the geometry of the external import is not easy to find the absolute coordinates of the center, the more trouble. In modeling, because the deformation of rollers is negligible relative to sheet metal, taking into account the springback problem of plates, the center roll and two side rollers are regarded as rigid bodies, and plates as elastoplastic ones. When the model is set up, the grid will be divided. Because the rollers are rigid bodies, and the temperature changes little during the roll bending process, so the three rollers do not need to divide the mesh. The quality of the grid division directly affects whether the simulation can be carried on, and the grid (local) is simulated.