Avaliação da integridade estrutural de um vaso de pressão danificado por trincas: análise numérica e adequação ao serviço.

Abstract

Intending on having a better engineering analysis (remaining life assessment) versus lower interventions (equipment stop for maintainance) Fitness For Service (FFS) standards were elaborated to explore the load limits, allowing the use of damaged structures and components in a more efficient way, extending their operational campains. This thesis implemented the FFS procedures of the American standard API 579/ASME FFS-1 (2016) and the British standard BS 7910 (2013) by the analysis of a surface longitudinal crack on the external surface of a cylindrical pressure vessel, in each level of assessment of each standard so that a comparison between each standard could be performed to evaluate which one is capable of providing higher critical dimensions that in real situation would mean higher operational time of dmamaged structures and components. FEM was used through the ABAQUS® software. Results indicated that in all comparisons of the 3 (three) assessment levels of each standard, BS 7910 (2013) provided a less conservative engineering critical assessment since, by both numerical and analytical solutions, this standard was able to determine higher critical sizes in comparison to the American standard. As a general concluding remark, BS 7910 (2013), since the absorption of the FITNET (2008) procedures, has become a much more practical and less conservative procedure when compared to the API 579/ASME FFS-1 (2016).