Effects of local departures from nominal dimensions on stresses in thin torispherical end closures

Abstract

A detailed survey (1-4)† of the variations in crown curvature, knuckle curvature and thickness of a number of thin torispherical pressure vessel ends has shown that actual dimensions may differ significantly from nominal dimensions. Numerical stress analysis using the finite element method has been carried out to assess the effects of these shape imperfections on the stresses in some of the thin torispherical pressure vessel ends considered in reference (4). The results have been compared with those for the corresponding perfect ends. In several cases significant increases in stress levels are predicted due to thickness and especially curvature variations.