Research on three-dimensional curved surface rolling based on rigid arc-shaped rollers

Three-dimensional curved surface rolling is a new method for forming curved surface metal sheets using the rigid rollers with variable cross section. The roll gap is determined by the arc radii of concave and convex rolls as well as the reduction to the metal sheets. After passing the roll gap, the metal sheet is nonuniformly compressed in the thickness direction and elongated in longitudinal direction, which leads to the deformation of metal sheet in rolling direction. Simultaneously, under the bending force of arc-shaped rollers, the metal sheet is continuously formed into a three-dimensional curved surface part. The work describes the deformation mechanism in the thickness and longitudinal direction and uses the FE (finite element) simulation to determine the arc radii of convex and concave rolls. A prototype device is designed, and the experimental results of convex surface and saddle sheets are presented. By theoretical analysis of deformation, FE simulation of process parameters, and forming experiments of different shapes, the feasibility and rationality of the proposed new technology are verified for forming the three-dimensional curved surface metal sheets, especially the parts with small transverse bending radius.