Stress Concentration in Heavy-Walled Cylindrical Pressure Vessels - Effect of Elliptic and Circular Side Holes

Abstract

This work was done to establish realistic stress concentration factors for side holes in cylinders. Contrary to intuitive reasoning, the circumferential stress at the cylinder bore-circular side hole interface is intensified by a factor less than 3.0. These factors for both elliptic and circular side holes approach a maximum with increasing ratio of outside to inside diameter of the cylinder and with decreasing size of the side hole; elliptic holes give rise to stress concentrations at the critical location, less than those induced by the presence of circular holes. The practical significance of the results lies in the fact that realistic stress concentration factors can be determined, so that overdesign is avoided. Some vessels heretofore considered impractical can be used with elliptic rather than circular side holes. (auth)