Under Pressure evaluates structural capabilities, deflections, and weights of common pressure vessel geometries such as cylindrical tubes, spheres, as well as hemispherical, conical, flat circular, and flat annular end enclosures.
The user can choose from a housing shape of tube, sphere, or end cap. Within the end cap category are several subcategories, such as hemispherical and flat annular. The flat annular end cap can be further delineated by choosing among several options, such as fixed, simply supported, guided, and free. The user also selects the material, housing component geometry, and pressure analysis range; the stress analysis is then rapidly calculated. A design loop can be selected and the analysis can be repeated while a single parameter (e.g. wall thickness) is varied. Stresses and deflections are given for internal or external pressures, over a user-selectable pressure range. English or metric units can be specified. The program uses equations from Formulas for Stress and Strain, sixth edition, by Raymond J. Roark and Warren C. Young.