Corrosion defect assessment on pipes using limit analysis and notch fracture mechanics

Two methods of corrosion defect assessment on pipes are described: limit analysis (LA) and notch modified failure assessment diagram (NMFAD). Limit pressure analysis are based on ASME B31G, modified ASME B31G, DNV RP-F101 codes and recent proposed formulation. The notch stress intensity factor concept and SINTAP structural integrity procedure are combined to assess pipelines integrity into a notch-based assessment diagram so-called ‘NFAD’. Defect assessment is made by comparing safety factor to a prescribed value (deterministic approach) or probability of failure to a conventional level.