Production offshore units have a relative long operational life (about 20 years), during which are submitted to the ocean adverse environment loading produced by the combination of wind, waves and currents. This complex loading history can promote the nucleation and propagation of cracks in mooring line components. The presence of defects establishes a critical situation that can lead to catastrophic failures. In spite of residual stress plays a preponderant part in the structural integrity of a mechanical component, the presence of residual stress is not considered in traditional design of these mechanical components. Therefore, is fundamental to develop new and more precise methodologies for assessing the structural integrity of mooring components. The present contribution regards on modeling and simulation of the residual stress distributions in studless chain links using a tri-dimensional elastoplastic finite element model with large displacements. In the analysis three material conditions, associated with different mechanical properties, were considered. The results indicate that the presence of residual stresses modify significantly the stress distribution in the component. Also, residual stress distribution depends on the mechanical properties of the chain link material. The structural integrity of the mechanical component was studied using the concept of critical volume associated to the material volume susceptible to a certain critical crack size. This methodology permits the evaluation of the critical crack length distribution related to brittle fracture of the component.

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