Offshore Construction – Installing the World's Deepest FPSO Development

Webb, Carl M. (Shell Turret and Installation Lead) | Vugt, Marco van (Stones Installation PM, Heerema Marine Contractors)


AbstractThe Stones project is located in the Walker Ridge (WR) area approximately 200 miles due South of New Orleans in ~9500 feet of water. The host facility is a Floating Production Storage and Offloading (FPSO) vessel with a disconnectable moored turret buoy (BTM) that allows the FPSO to move off site in a hurricane event. Each of the nine moorings are made up of a suction pile – chain – polyester – chain – spring buoy – top chain assembly. These connect to the circumference of the BTM at the keel. The subsea infrastructure, including 2 flow-lines, one gas export pipeline, and two umbilicals, are supported by the BTM. The pipelines and all umbilical fluids, electrics, and fiber are connected or disconnected from the FPSO via dry internal turret connection systems.This paper provides an overview of the transportation and installation of the moorings, turret buoy.Key challenges include water depth world record for FPSO moorings, transportation and handling of the world's largest disconnectable buoy, and project execution during an extreme eddy current event.