Application And Optimizing Analysis Of Two-Point Mooring Offloading System In Offshore Oil Development

Two-Point mooring offloading system is used for offshore oil development&production in China and CNOOC for the first time. Mooring conditions designed for theoriginal system are wind force less than grade4, wave height less than1.25m, which ishard to satisfy the actual practical requirements of offshore production, resulting to oilfieldshutdown many times. Risks and problems existing in the first application of this systemare summarized in the paper; an emergency plan of Two-Point offloading project inCNOOC is prepared for the first time. In addition, through modification and optimizationof the salvage method, length, diameter of floating guiding lines and delivery of offloadinghoses, the improved system can withstand wind force up to grade6, wave height less than2.5m, thus increasing the offloading possibility greatly and ensuring the normal operationof oilfield. Just calculating$1808640profit (in offloading capacity3600m3/tanker, crudeoil$80/barrel) can be gained by the crude oil of one more offloading shuttle tanker in aconservative way, several$1808640profits can be gained in one year. Not only greateconomic profits can be gained by the improved Two-Point mooring system, it can alsoprovide CNOOC with practical experiences for development of the following similarmargin oilfields.