New Build Generic Large FPSO

Abstract The increasing demand for FPSOs and constant pressure for ever shorter delivery times has motivated SBM to design conversions and new-build hulls in a generic manner. SBM has been designing successfully generic FPSOs using converted VLCC hulls, based on a rationalized deck layout with integrated power generation and process equipment. Over a period of 3 years, this generic conversion design has been applied to a series of 7 FPSOs that will be briefly described in this paper. In order to meet the increasing world-wide demand for large new-build hulls, SBM has designed a generic hull with a storage capacity of 2mmbbls or 2.4mmbbls, capable of supporting large topsides with a high level of flexibility in the process layout and using a similar philosophy to that developed for the generic hull conversions. Typical machinery and accommodation blocks are proposed permitting future modifications to be tailored to specific requirement. This new-build hull design will permit fast track hull construction and FPSO delivery. Introduction FPSO designs, whether based on converted tanker or new-build hulls, are governed by a number of key technical factors:- typically the storage capacity, production capacity, export capacity, site environment and crew complement. However, a key non-technical factor affecting the entire project organization and major technical decisions is time schedule which is a significant challenge for designers. There is obviously a need for a fast track method for building or converting FPSOs. However, it is unreasonable to expect to simply squeeze indefinitely all project activities to achieve significantly reduced delivery times: this would result in unacceptable risks during design and construction, with commensurate risks to the performance of the unit. Those conflicting requirements triggered an alternative approach to manage a fast track FPSO project, the so-called generic approach. At the end of 1999 SBM and Gusto invested time in screening all aspects of tanker conversion; defining a basis of design suitable for a wide range of applications and carried out an internal engineering study in preparation for expected future FPSO conversion projects. This investment proved to be very fruitful. The design was used in several projects including the FPSOs Falcon, Atlantic and Serpentina for ExxonMobil, FPSO Espadarte, Brasil and Marlim Sul for Petrobras and FPSO Mystras for Agip. The design is also currently proposed on many other projects. Despite the success of generic conversions, new-build hulls may be required for FPSO projects. This paper will first address FPSO conversion background and explain the main drivers for new build hulls. Then, the generic hull, including the basis of design, the structure, the hull systems and the interfaces with topsides plant, will be presented. Finally, construction phase and operational feed-back will be addressed briefly based on the experience gained as both prime contractor and leased vessel operator.