Analysis in Mooring Chain Links Tensioned on Curved Surface

Resumo

The development of offshore energy resources, specifically oil and gas, is increasing. Consequently, there is an increasing demand for state-of-the-art technologies and concepts to enhance productivity in this sector. One critical component of deep and ultra-deep water floating platforms is the mooring system, which requires rigorous design considerations. The motivation behind this lies in the substantial repair costs associated with unexpected failures. Structural failure in anchor chain links is primarily attributed to fatigue damage. While extensive studies have explored this phenomenon, the impact of mooring equipment with curved surfaces responsible for guiding or restricting the upper end of mooring lines on chain link behavior remains somewhat overlooked. In this study, we investigate the effects of ungrooved curved surfaces on the fatigue life of tensioned offshore mooring chain links. Using Finite Element Analysis (FEA), we analyze the behavior of mooring chain links when subjected to tension on curved surfaces. Our findings identify stress hotspots and calculate the corresponding Stress Concentration Factors (SCFs). Notably, the presence of curved surfaces significantly influences stress distribution and fatigue life. Additionally, we explore the effects of varying nominal stress levels applied during assembly and changes in the radius of the curved surface. These results have important implications for the design of mooring systems used in oil and gas exploration and production.