Abstract

The installation of FPSO moorings in deep water will become increasingly more common as fields previously regarded as not viable become feasible due to increasing demand combined with improved drilling and production techniques.

The development of the Aquila field offshore Italy in the Adriatic Sea for FPSO Firenze Producao de Petroleo Ltd (FFPP) [a joint company of SBM and Saipem] on behalf of Agip calls for the installation of an FPSO in 823m (2790 feet) of water. This will be one of the deepest ever installations of a moored FPSO system and for a short time will also be the deepest subsea installation in the world. (Refer to Figure 1 and Figure 2)

Installations in these extreme water depths create enormous challenges to existing installation technology and equipment The need to carefully plan for all possible contingencies is paramount since the ability to overcome many problems on an ad hoc basis becomes almost impossible.

This paper deals with the technical and practical aspects of the FPSO mooring installation. Although installation of the wellhead manifolds and flowlines also present an enormous challenge, they are not included in the scope of this paper.

Several mooring designs have been investigated by FFPP including suction anchors, piled anchors, as well as conventional drag anchors. This paper describes the technical issues leading to the ultimate selection of suction anchors and the subsequent installation methodology currently being developed by the nominated installation contractor, SaiCIo.