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In this paper, the roller (three-roll) molding of a plate stock, based on elastoplastic bending, is investigated. Physical models of the deformation zone during the interaction of the workpiece with rolls are presented considering two stages: when the upper roll is moved without rotating the rolls and when all three rolls are rotated without moving the upper roll. The results of an experimental study of the deformation zone parameters are obtained, and they are used to determine the profile of the tubular billet during molding on a specialized bending machine, for the two stages of the bending process. The experiments showed that for the first bending stage, the billet in the zone of separation from the upper roll has a complex curvature and symmetrical three-point and four-point contacts with the rolls. The second stage of bending with the rotation of the rolls is characterized by an asymmetric deformation zone during three-point contact. Finally, the regression equations for the geometric parameters of the bent workpiece profile sections are obtained. [ABSTRACT FROM AUTHOR]

A longitudinal-wedge mill of new design is proposed. We present the analysis of the results of mathematical modeling of the elastic deformation of heavy-duty components of the stands of the new mill with the use of the procedure of computer simulation by the finite-element method in the PATRAN-NASTRAN environment. The influence of changes in the diameter of working rolls of the longitudinal-wedge mill on the elastic deformation of heavy-duty components of the stands of the mill is determined. It is shown that the new mill is characterized by a fairly high stiffness of the structure of stands and satisfies the conditions of strength. It is indicated that the process of rolling of strips on the proposed mill makes it possible to obtain finished rolled products without variations in thickness in the longitudinal and transverse directions. As a result of modeling of elastic deformation of the heavy-duty components the stands of the new mill, we develop special measures for their modernization. [ABSTRACT FROM AUTHOR]

A procedure for the evaluation of the thermal conditions for the rolls of continuous casting machines operating in the conditions of scale formation in the cooling channel is proposed. The procedure allows a differentiated approach to the determination of the axisymmetric and maximum surface temperature of the rolls with allowance for the magnitude and behavior of the thermal load and the cooling and scale formation conditions on the heat-exchange surfaces. It can be used to predict the roll service life and to rate the quality of cooling water. [ABSTRACT FROM AUTHOR]