Standardization of FPSO Hull with 2MMbbls Storage Capacity for West Africa

Abstract

Abstract Standardization of offshore platforms is refocused to reduce costs and accelerate project delivery times. Some components or modules of offshore platforms are tried to be standardized in industry. There are also applications to use a standard platform itself. This paper describes the standardization of FPSO hull with 2MMbbls storage capacity for West Africa. The FPSO hull in West Africa is better to be standardized than ones in other sites, for most of new-build FPSOs in the world are in West Africa and many of their storage capacities are 2MMbbls. In design procedures, we focus on the selection of design basis and the design of hull configuration, tank arrangement and midship section. As a result, a standard model of FPSO hull is presented. For the standard model of FPSO hull to be competitive in West Africa, it could satisfy the requirements of this region. The past new-build FPSO projects in West Africa are investigated to premise the design basis such as the environmental conditions, topside weight and module layout, storage capacity, motion criteria, etc. Systematic procedures for each design items are presented in this paper. Firstly, the generic topside modules and their weight distributions are suggested. Initial hull sizing is carried out in terms of hull weight and motion characteristics. Hull bow and stern shapes are designed to achieve the towing performance for resistance and directional stability. Tank capacity plan, intact/damage stability and rule scantling for midship are checked for the design of hull configuration. The design procedure for hull sizing is automated with an optimization tool which provides Pareto-solutions to designers. Final standard FPSO hull has less weight and satisfies the general requirements in West Africa. The design procedures in this paper are applicable to early stage of field development and could correspond flexibly to various offshore fields.