Fatigue Assessment of a Weld Joint of a Pressure Vessel

A full-penetration weld on both sides between a shell and a flat head is evaluated for fatigue strength by four methods, two based on structural stress and two on notch stress. Internal pressure is cycled with constant amplitude. The allowable cycles are calculated by each method. The number of cycles for the same geometry and loading varies widely, ranging from 4,835 to 137,000.