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Abstract Shuttle tankers are normally employed for cargo transfer from FPSO (Floating, production, storage and offloading) and FSO (Floating, storage and off loading) units because they are the most practical solution in remote fields. Cargo offloading can be performed in a tandem configuration where the shuttle tanker is positioned a distance behind the FPSO or FSO unit, or in a ship-to-ship where the shuttle tanker is positioned a distance beside the FPSO or FSO unit. During the long-lasting production and storage processes, various types of mooring systems are used in offshore exporting/discharge oil such as spread mooring, single point mooring, turret mooring and conventional buoy mooring. A full description for each mooring system type had been illustrated in this report. selection of mooring system depends on several parameters such as FPSO or FSO vessel particulars, structural design of the vessel, weather criteria in service area, water depth in service area and nature of the seabed. A mooring system arrangement with the appropriate components shall be carried out and complied with The Oil Companies International Marine Forum (OCIMF) regulations, 2007 edition. In addition, during the offloading process, various types of failures may be occurred in offloading line and/or mooring lines with different scenarios. Collisions between shuttle tankers and FPSOs or FSOs are fortunately rare events, but in the case of an accident, the outcome can be catastrophic. That‟s why a risk assessment study had been added in this report to describe the main procedures to be taken in emergency cases.Theoretical studies based on the Orcaflex software theory, as illustrated in this report, shall be carried out to analyze the performance of the mooring and tandem mooring systems in various wind and waves effects. Full description for the analysis calculations methods of< Orcaflex software is included in this report. As indicated in the enclosed case study, which describes a complete mooring system study for an existing FSO vessel of 183 m length installation project in Suez Gulf, Egypt, a full detailed analysis process using the Orcaflex software has been illustrated including full input data, calculations results, mooring system design (in various wind and current directions) and specifications of mooring system components. This vessel was converted from oil tanker to be a full equipped FSO unit including the required modifications for the selected mooring system. |