Strip layer method for simulation of the three-dimensional deformations of large cylindrical shell rolling

A strip layer method is presented for analyzing the three-dimensional deformations and stresses of large cylindrical shell rolling process. In this approach, the different radii and velocities of upper and lower rolls, the uneven distributions of deformations and stresses at the roll gap, are taken into account. The rolling deformation zone is divided into a number of strip and layer elements along the width and thickness directions, respectively. In order to reduce the optimization parameters and improve the computation efficiency, the exit lateral displacement distribution is expressed as polynomial function. Based on the fundamental principles of plasticity, the three-dimensional deformations and stresses of the deformation zone are formulated. The simulation results can be obtained quickly and easily. The fishtail spread is predicted satisfactorily on the free side, and the rolling pressure distribution is quite different from that of a conventional strip rolling. The predicted rolling force and average spread of the proposed method are in agreement with the experimental and FEM results.