Aasta Hansteen Spar FPSO Substructure, Mooring, Riser and Systems Design

Abstract

Aasta Hansteen, located in 1300m water depth, is the first deep water field on the Norwegian continental shelf developed with a surface platform concept. It is in the Norwegian Sea and developed using a Truss Spar FPSO. It is the world's largest Spar platform substructure facilitated for continuous personnel entrance and with a large volume of condensate storage in the hull that is offloaded to a shuttle tanker. It is the first floating platform in a North Sea/Norwegian Sea harsh environment with steel catenary risers (SCR). It is the first Spar designed to NORSOK and other Norwegian regulations. The platform was made ready with platform mooring chain and topsides installed by floatover in a fjord before being towed vertically to the field.