Numerical simulation of the integral hydro-bulge forming of non-clearance double-layer spherical vessels: analysis of the stress state

摘要

The integral hydro-bulge forming (IHBF) of non-clearance double-layer spherical vessels is simulatednumerically by the explicit finite-element code LS-DYNA3D. The stress distribution, the straindistribution and the residual stress are discussed in the present paper. The numerical results showgood agreement with experimental results. Bulging deformation appears over most of the blank area;bending deformation occurs near to the blank edges and blank corners (shell vertices of theintersection area of weld seams), especially on the uncontacted areas of the outer shell; whilst hightensile stress exists at the inner surface. The residual stress may be reduced to below 20% of the yieldstress of the material after bulging.