scope:

The Bulletin presents a comprehensive numerical study in which a large number of Mode I stress intensity factor ( ) solutions for cracks in plates and shells were generated for inclusion in the American Petroleum Institute (API) Recommended Practice on Fitness for Service (RP 579). A series of 2D and 3D finite element analyses were performed on plates, cylinders, and spheres containing surface cracks and buried cracks. A wide range of flaw aspect ratios at radius/thickness ratios were considered. The results of these analyses are tabulated. The Bulletin also describes a weight function methodology in which solutions for arbitrary through-wall stress distributions can be derived for surface cracks in plates and shells. The weight function for a given geometry and crack size is derived from reference solutions for uniform and linear crack-face pressure. The necessary reference solutions for surface cracks in plates, cylinders and spheres are provided