The Design Of Mooring System For 86000 DWT FPSO

The development of economy has brought huge consumption of oil, gas and other energy source, while the land storage of fossil energy could not meet the growing demand. So human has turned the objectives of energy development to ocean through the development of marine oil and gas resources to make up the lack of land resources. In the process of offshore oil development, Floating Production Storage and Offloading system (FPSO) is an oil extraction,storing and processing integrated production platform. FPSO needs high locating capability mooring system to ensure its safety work for its long-term working in the sea. So how to design a safe and economic mooring system is very important.This preliminary plan of mooring system is provided. Choose the catenary's mooring line consist of chains and wire rope two components as the mooring mode for a specific 86000 DWT FPSO. Reasonable mooring plan is selected by analyzing effect of layout angle,pretention force and wire rope length on mooring system. Suitable anchor's type and size are selected according to the maximum force of mooring line. The main works in this paper are as follows:Hydrodynamic response and average second order wave force of FPSO in the regular wave, and its RAO of the six freedom degrees movement are also calculated to provide the necessary calculation basis for mooring system time domain analyze by using AQWA software. And the effect of pretention force and wire rope length on mooring system is analyzed.Considering the impact of pretension and wire rope length on mooring system, choose the better design plan of mooring system. Calculation and check are done by selecting time domain method in AQWA software.Choose suction anchor as suitable anchor according to the seabed geological conditions and its appropriate size is selected. Formula method and finite element method are applied to check its bearing capacity. And the best mooring position is determined by the calculation results. Select the appropriate windlass type based on chain pretension, its reinforcement structure members are designed and foundation strength is analyzed.