THREE-DIMENSIONAL MODEL OF EQUIVALENT ROLL GAP OF CVC MILL UNDER CONDITIONS OF ROLL CROSSING AND NO LOAD
Abstract
Traditional roll technologies focus solely on the contour of the roll gap at the outlet under ideal conditions. However, upon roll crossing, the three-dimensional distribution of the deformation zone becomes asymmetrical, leading to an adverse impact on the rolling pressure in the deformation zone. To study the screw-down load deviation of plate mills, it is necessary to accurately calculate the equivalent three-dimensional roll gap in the deformation zone under roll-crossing conditions. In this paper a model for calculating the equivalent three-dimensional roll gap under the conditions of roll crossing and no load was established based on the method of the coordinate nonlinear transformation of the spatial rectangular coordinate system. Based on this model, the influences of roll-crossing angles and translation parameters on the symmetry of the equivalent three-dimensional roll gap were analyzed. The distribution of the three-dimensional equivalent roll gap was calculated with different roll lengths, roll radii, and the roll gap’s nominal thickness. The intuitive contour map reveals that under the same condition of crossing angle and translation parameters, the larger the roll length and roll radii and the smaller the roll gap’s nominal thickness are, the greater the influence of the roll crossing on the asymmetrical distribution of roll gap is. It put forward a quantitative calculation method for evaluating the symmetrical distribution of the roll gap, and the calculation results can provide the equivalent roll profile for the roll-deformation model.
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