Mi Wang

Numerical Investigation on the Process of Stretch-Forming Based on Discretely Loading for Spherical Sheet Metal Parts

Stretch-forming based on discretely loading is a new process for manufacturing three-dimensional sheet metal part, the stretching load is applied at discrete points on the two ends of sheet metal, by controlling the loading trajectory at each discrete point, an optimal stretch-forming process can be realized, and the formed surface with the strains and stresses more uniformly distributed are obtained so that the forming defect can be avoided. The numerically investigated results on the stretch-forming process of spherical sheet metal part show that, comparing with the traditional stretch-forming, the equivalent strain in the new process is reduced by approximately 30% and equivalent stress reduced by 10%, the range of the strain and stress distributions are reduced by approximately 30%.

Numerical Investigation of Continuous Roll Forming for Three-Dimensional Surface Parts

Continuous roll forming is a new technology for manufacturing three-dimensional surface parts. Extensive numerical simulations of continuous roll forming process were carried out. The influence of the middle curve and the magnitude of the roll gap on the longitudinal curvature of formed parts is investigated. Wrinkling is one of the most important defects for the formed parts in continuous roll forming process. A simplified model was established for analyzing the wrinkling of saddle-shaped part and torus-shaped part. The simulated results show that the wrinkling of saddle-shaped part is located at the edges, and the wrinkling of torus-shaped part emerges in the vicinity of middle region.

Rolling Process for the Continuous Forming of Curved Surface Parts Based on Bended Rolls

A new sheet metal forming process which can form three-dimensional surface rapidly, effectively and with lower-cost has been proposed. This paper mainly focuses on the fundamental aspects of the process. The principle of the rolling process based on bended rolls is introduced, and the methods to calculate the longitudinal bending deformation and to design the roll gap are presented. Experiments for typical surface parts are carried out. The forming results of convex surface and saddle shaped surface parts are measured and analyzed, the analyzed results demonstrated that the proposed process is a feasible and effective way of forming three-dimensional surface parts.