INVESTIGATION OF LONGITUDINAL STABILITY PROCESS AT ROLLING WITH STRIP TENSION

Abstract

Earlier in the works, a qualitative construction of the diagram of changes in longitudinal normal stresses in the case of thin-sheet rolling with strip tension was proposed.. On the basis of the proposed stress distribution, the internal longitudinal forces were determined in a dimensionless form. Knowing these values, it is possible to determine the average resultant longitudinal force of the plastically deformed metal during rolling with the strip tension. It is shown that the value of the mean resulting internal forces is a more stringent boundary condition for the rolling process than the equality of the angle of the neutral section to zero.In this work, the influence of the strip tension mode on the ultimate stability of the metal in the rolls was determined, as well as the limiting condition of rolling, the change in the moment in the deformation zone and the angle of the neutral section. The theoretical analysis was carried out proceeding from the solution of the equilibrium equation with the specific friction forces specified by the Coulomb model. Using the technique proposed in previous works, we studied the effect of the magnitude and mode of strip tension on the longitudinal stability of the sheet during continuous rolling. It is shown that the rear tension has a significant effect on the average resultant longitudinal internal forces, and thereby predetermines the boundary conditions of the rolling process. The boundary conditions of deformation in a steady-state process presented in this work and generally accepted in theory differ significantly, which should be taken into account when developing a technology for continuous sheet rolling.