Analysis of efficiency criteria for evaluation of slab widthwise reduction

The choice of efficiency criteria of slab widthwise reduction is quite challenging. The criterion should fairly reflect the information about the on-going process of study and its trends, the measurable parameters should be available for measurement. Only in this case the criterion can be used to assign an effective technology of slab reduction. The paper deeply analyzes the formulas presented by many authors for calculating the efficiency criterion, which were created to analyze the reduction considering the importance of various parameters. Using the finite element method slabs of different widths were rolled in vertical grooved rolls with the subsequent horizontal reduction in smooth horizontal rolls. Based on the geometric parameters of the simulation results the calculation of criteria for the analyzed formulas is presented. Based on the calculation results of the formulas being analyzed, their peculiarities and field of application are emphasized. A formula is proposed for the efficiency criterion evaluation considering possible rolling options, i.e. rolling in vertical rolls only, rolling in vertical rolls with subsequent smoothing passage, and rolling in vertical rolls with subsequent horizontal reduction. Recommendations are provided on the formulas selection for a faithful description of the process considering possible rolling options.