A Study on the Structural Impact of FLNG Topside Piperack Module Enlargement

To minimize the production time of floating liquefied natural gas (FLNG) units, which are eco-friendly offshore structures, builders are exploring methods to extend the length of piperacks. This approach aims to reduce the number of installations and equipment required. In this study, a static stability analysis (in-place analysis) was conducted using the structural analysis computer system (SACS), a program for analyzing topside structures, to assess the effects of piperack enlargement. Two models were analyzed: the original piperack and a version with double the length. Both models were based on data from an existing FLNG unit, with identical environmental loads applied. The results showed that while relative displacement increased linearly with length, the stress did not follow the same linear pattern. However, stress levels in some braces at the base of the structure increased, indicating the need for larger structural members. From the perspective of in-place analysis, piperack enlargement appears feasible. However, further investigation, including fatigue analysis and assessments of operational and maintenance challenges, is recommended to confirm its long-term viability.