“…When this happens to a pressurized vessel, the occurrence of leakage may signal the onset 4 1 Introduction to Residual Stresses of a fast moving crack that has already penetrated much of the thickness [53]. For the second case, consider a thin-walled cylinder with a circumferential weld, which introduces a locked-in moment M o [40]. As a circumferential crack grows, the magnitude of the moment M (a/t) reduces as the compliance of the cracked cylinder increases, as shown in Fig.…”