100 cubic metre (65 tonne uplift) Stabilising Buoy used for the controlled lowering of the 3,000 tonne concrete caisson gravity base. Shown being recovered to the Stolt Offshore DSV Discovery.  This buoy was connected to the gravity base via a wire pennant and pipe tripod structure.  Our obligations were to design, fabricate and supply the buoy and ancillary rigging. The buoy was multi-compartmented to allow for controlled flooding and evacuation of the 11 compartments, with each compartment and separating bulkheads being capable of resisting 110 m of submergence pressure.

The structure was built and test assembled in Johannesburg in 4 transportable sections (central pontoon, lower pontoon pair and two side pairs), and reassembled and welded together in the Cape Town docks.  The central pontoon was fitted with a 100 Tonne pad-eye top and bottom.  The time between award and delivery was ten weeks