DOT 2013: First-ever spar offshore Norway sets new records

Work is progressing on the world’s first spar FPSO which also is the first deepwater project offshore Norway.

Offshore staff

THE WOODLANDS, Texas – Work is progressing on the world’s first spar FPSO which also is the first deepwater project offshore Norway.

In discussing the Aasta Hansteen project at the Deep Offshore Technology Conference, Oddgeir Dalane of Statoil said the development concept calls for two four-slot templates and satellites in as much as 1,300 m (4,265 ft) of water about 300 km (185 mi) from shore.

The spar has storage capacity for condensate, which is novel. “One result of the storage and the harsh conditions is that this will be the largest ever spar,” said Dalane. “It will be 51 m (167 ft) in diameter with 21 m (69 ft) of freeboard and about 200 m (656 ft) long. The condensate storage means the structure has to have a compensating ballast system.

“The waves are the most important consideration of the harsh elements. That and designing to NORSOK standards resulted in the size of the spar.”

Because of the ballast requirements and the rigor of the NORSOK standards, Statoil was not able to just extrapolate from its experience with a spar in the Gulf of Mexico, Dalane said.

Another notable difference for this structure is that it will have a 17-line taunt mooring system constructed of polyester rope. A cut resistant jacket will protect the mooring lines from the trawler fishing vessels in the area.

The recoverable gas estimate at Aasta Hansteen is 47 bcm (1.66 tcf).

Among the contracts let to date, Hyundai Heavy Industries will build the deck and living quarters. The hull is contracted to Technip and Hyundai. Subsea 7 has the contract for the subsea lines and marine operations.

10/23/2013

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