Roll fattening is an important component in the roll stack elastic deformation, which has important infuence on controlling of the strip crown and fatness. Foppl formula and semi-infnite body model are the most popular analytical models in the roll fattening calculation. However, the roll fattening calculated by traditional fattening models has a great deviation from actual situation, especially near the barrel edges. Therefore, in order to improve the accuracy of roll fattening, a new model is proposed based on the elastic half plane theory. The calculation formulas of roll fattening are deduced respectively under the assumptions of plane strain and plane stress. Then, the two assumptions are combined through the method of introducing an transition coefcient, and the distribution rules of roll fattening for diferent rolling force, fattening width, roll length and roll diameter are analyzed by using the FEM analysis software Marc. Regarding the ratio of the length to roll end and the roll diameter as variable to ft the transition coefcient, the new model of roll fattening is established based on the elastic half plane theory. Finally, the transition coefcient is ftted to establish the model. Compared with the traditional models, the new model can efectively improve the calculation deviation in the roll end, which has important signifcance for accurate simulation of plate shape, especially for the distribution of rolling force between rolls.
Roll fattening is an important component in the roll stack elastic deformation, which has important infuence on controlling of the strip crown and fatness. Foppl formula and semi-infnite body model are the most popular analytical models in the roll fattening calculation. However, the roll fattening calculated by traditional fattening models has a great deviation from actual situation, especially near the barrel edges. Therefore, in order to improve the accuracy of roll fattening, a new model is proposed based on the elastic half plane theory. The calculation formulas of roll fattening are deduced respectively under the assumptions of plane strain and plane stress. Then, the two assumptions are combined through the method of introducing an transition coefcient, and the distribution rules of roll fattening for diferent rolling force, fattening width, roll length and roll diameter are analyzed by using the FEM analysis software Marc. Regarding the ratio of the length to roll end and the roll diameter as variable to ft the transition coefcient, the new model of roll fattening is established based on the elastic half plane theory. Finally, the transition coefcient is ftted to establish the model. Compared with the traditional models, the new model can efectively improve the calculation deviation in the roll end, which has important signifcance for accurate simulation of plate shape, especially for the distribution of rolling force between rolls.
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