..., the thickness of the obround shell should increase accordingly, to keep the maximum hoop stress of obround shell consistent with the maximum hoop stress of the parent cylinder. The minimum requested thickness (MRT), of the obround shell is related to the MRT of the parent cylinder and the flattened shell length...

...Roberto Brighenti A round pipe with an external longitudinal surface flaw is assumed to be subjected to different types of elementary hoop stress distributions acting perpendicular to the crack faces. The stress intensity factors (SIFs) along the crack front for such elementary cases are determined...