The contract for the turret mooring system for Marathon’s Alvheim FPSO is the largest ever won by Advanced Production and Loading. It also represents a step change in submerged turret technology, of which this company is the sole specialist.
Alvheim is the fifth field development to incorporate APL’s submerged turret production (STP) system, but only the first in the Norwegian sector. The STP buoy, which together with the swivel will weigh around 700 tons, will accommodate up to 13 risers and umbilicals. It will be moored with 12 anchor lines in a water depth of 125 m in the North Sea.
The scope of the +NKr400 million contract is also the widest undertaken to date by APL, according to vice president Fredrik Major. In addition to the turret and swivel, the company will supply the whole hull insert in the tanker bottom in which the turret and ship are mated. The scope extends to all dedicated equipment in the vessel’s STP compartment, which runs from the deck where the turret is locked into position up to the main deck. This includes locking mechanisms, handling equipment for taking the load of the swivel, rotating sheaves for the pull-in wire, and the pull-in winch. The delivery will be made in stages this year and next.
APL also has a letter of intent from Mærsk Contractors to supply a submerged turret loading (STL) system for Statoil’s Volve project in the same sector. The development plan was submitted in February. The system, due for delivery in 2006, will moor Teekay Norge’sNavion Saga tanker, which will act as an FSO unit. In this case, APL will supply a refurbished system previously used on Shell’s Fulmar field in the UK North Sea.
This demonstrates the flexibility of a standardized turret mooring system, which is independent of the vessel used, Major says. Another benefit is that when the vessel is released from service, it merely detaches from the buoy and sails off to a new assignment - it does not need to go to port for modifications.
Last year APL supplied an STL system for Excelerate Energy’s Energy Bridge in the Gulf of Mexico, the world’s first offshore LNG regasification plant. The first LNG delivery to the plant was due in March. Studies have been performed for other proposed offshore regasification projects. Among other current orders, the company is supplying its single anchor loading system to Petro-Canada’s De Ruyter development in the Dutch sector, essentially a repeat order of the system supplied a few year’s back to the same company’s Hanze field.
