Rolling simulation system for non-symmetric groove types

Abstract

An extension of a previously developed rolling simulation system is presented. Complicated groove dimensions, which have no longer symmetry on any of the coordinate axis, are successfully implemented. The thermo-mechanical numerical solution, considering ideal plastic deformation and obeying von-Mises flow rule, is based on meshless local radial basis function collocation method. During the solution procedure, 2D discrete cross sectional slice of a groove and rolled material become a computational domain at a given time, parallel to each other and aligned perpendicular to the rolling direction. Groove slice, or groove surface lines, are created with the help of imaginary groove surface points for each slice position. The implementation of roll contact at the boundaries is done by considering possible contacts of a slice and groove surface line at multiple sections with different deformation rates and boundary conditions. Coulomb model of friction is considered at the contact boundaries. The design of non-symmetric (in vertical or/and horizontal direction) type of rolling schedule is quite complicated since keeping the rolled product at the center may become problematic and unexpected deformation in one direction could ruin the desired final shape. The computational model, capable of coping with non-symmetric groove geometries provides an essential simulation tool for these type of roll pass designs. To increase the stability and the accuracy, the number of collocation nodes over the slices as well as groove surface points may be suitably increased or redistributed. The simulation results are shown in terms of temperature, displacement, strain and stress fields as well as roll forces and torques. A user friendly computer application is created for industrial use based on C# and .NET.