Optimizaton of rough rolling stage in hot rolling process by modeling

The aim of this study is development of a solution to cope with sequential nature of hot rolling process which is the main factor making the optimization of the process intricate. A solution search strategy based on desirability functions has been developed to get this aim. In addition, an optimization method is suggested to use developed strategy in roll pass design. Besides restrictions required by sequential nature of the process, geometric and technological restrictions are also considered in the developed solution search strategy. A case study has been conducted for demonstration and validation of solution search strategy and suggested optimization method. Optimization of a rough Rolling process with 5 passes has done in this scope. The main goal of the optimization study is to minimize total deformation energy consumed in the process and the secondary goals are to reduce radial forces and turning moments acting on the rolls. The optimization study is consisting of two stages. Optimum width and height values of box pass geometry used in rough rolling have been determined in the first stage. Optimum values of minor geometric parameters i.e., angle and radii have been optimized in the second stage by using optimum width and height values. The results of the case study have been compared with three reference industrial pass sequence designs. As a result of optimizations deformation energy, radial forces and turning moments are reduced by 18.78%, 7.46% and 10.25% respectively with respect to average values of reference industrial designs. Solution search strategy and roll pass optimization method developed in this thesis study are available to be used in the industrial rolling processes.