The H-beams rolling investigation for the standard roll groove using the toal-power minimum variational principle
The formulation and solution of the problem of double-T section rolling in universal groove using the variational principle of minimum total power with aim to determine integral forming and energy-power parameters are presented. Geometrical model of the deformation zone and the kinematically admissible velocity field were constructed accurate within two unknowns: forward slip coefficient ν, flange spread (pulling-down) ∆hф. To determine the unknown parameters ν and ∆hф two equations were used: variational equation of the principle of minimum total power for stiff- plastic medium; power balance equation. The numerical solution was made by the method developed at the department of metal forming of «UrFU named after the first President of Russia B. N. Yeltsin». The comparison of the calculated values with the experimental data obtained on a laboratory mill 200 and on universal beam mill NTMK confirmed that the the variational principle of minimum total power has sufficient accuracy for analysis of double-T section rolling in universal groove. The mean statistical error of torque calculation is 12,7 % while load calculation is 20,7 %.