Buoy platform concepts

The Buoyform concept is a concept without turret, with favourable motion characteristics, enclosed moonpool and a simple and cost effective fabrication. The floater is a conically shaped structure with significant damping characteristics that gives substantial improvement in motion response compared with other floaters and ship-shaped hulls. The solution has been extensively studied and tested, offers opportunity for simultaneous drilling and production operations.

Another early buoy concept was the offloading buoy for the Draugen field. This design was delivered from Aker Solutions’ yard at Verdal, Norway, in 1995.

In the late 1990’s, Aker Solutions was responsible for the delivery of Spar platforms for the Neptune, Genesis and Hoover/Diana developments, from its facilities in Houston and Pori. This part of the organisation was divested in 2000, but key experience is still within the organisation.

Another concept that was initially conceived in the 1980’s is the Condeep™ Monofloater. This concept has been further developed and tested in recent years, as particularly relevant for harsh environments, thanks to the long term durability and ice load tolerance. The concrete construction additionally offers the potential for local construction also in remote locations.

The most recent buoy development has targeted arctic areas and ice loads. Minimising the ice load requires a narrow waterline with ice breaking features. The design has to be developed in interaction with ice load testing and several campaigns have been undertaken, in cooperation with operators of arctic developments.

Aker Solutions has in the period 2008-2010 executed a joint industry project (JIP) with Statoil, Chevron, Shell, ExxonMobil and the Norwegian University of
Science and Technology (NTNU), where potential platform concepts have been tested in different drift ice conditions. Several moored buoy concepts have been tested and effect of different structure properties have been compared with respect to the measured response, mooring load and motions, of the buoys in different ice conditions. The project has increased the understanding on how to design buoys for areas with drift ice and the results of the project will be used to further develop methods for estimation of ice induced mooring loads on floating platforms.