The offshore operational experience has shown that the flexible pipe end fitting (EF) may be the weakest point in terms of fatigue resistance of the tensile armor layers. The findings observed in dissections from risers which were in operation or subjected to qualification tests reveal that there is a key point with respect to fatigue inside the end fittings. This point corresponds to the section in which the wires of the tensile armors are subjected to significant plastic strains caused by the end fitting assembly process. Thus, this study aims to propose an analytical approach to predict the fatigue resistance of flexible pipes focusing on their terminations. A local analytical model is employed to predict the stresses induced in tensile armor of the pipe due to the end fitting assembly and also during operation. These stresses are used in conjunction with a previously detailed approach that is employed to compute the fatigue resistance of flexible pipes. The methodology is validated by comparing its results to several real scale prototype tests. The results obtained during validation showed that the application of this methodology in calculating the fatigue life has low variability and therefore the failures observed in the qualification tests are well predicted. This methodology has been successfully used by Petrobras in flexible risers life extension.
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