Numerical Determination of Stress-and-Strain State in Rolls and Counter-Bending Forces in Four-High Mill Stand

Numerical methods are developed and program means are created for the numerical determination of stress-and-strain state and counter-bending forces of the four-roll mill of cold plate rolling taking into account of residual temperature stresses. Computation of temperature stresses is performed by solving the thermoelastoviscoplasticity problem for a medium with nonstationary structure. The ANSYS finite-element complex is used as a basis for solving the 3D-contact problem to determine working stresses of rolling. Numerical results as applied to the real rolling mill "Kvarto 500/1300 1700" are presented. It is found that the approximated analytical solution based on a girder scheme provides understated values of counter-bending forces and also that residual stresses caused by the roll thermal processing are much more than operation stresses caused by the rolling.