Extended draft platform makes marginal fields feasible

A new dry tree floater could make marginal fields worth developing, according to John Murray, principal engineer at Technip. Murray told attendees at the eighth annual Offshore West Africa conference in Abuja, Nigeria that the new concept is applicable offshore Africa.

A new dry tree floater could make marginal fields worth developing, according to John Murray, principal engineer at Technip. Murray told attendees at the eighth annual Offshore West Africa conference in Abuja, Nigeria that the new concept is applicable offshore Africa. "The number of smaller to medium-sized dsicoveries is growing in the region," he said.

The underlying strategy to making these fields economically attractive is to reduce or defer capital costs, keep operating costs at a minimum, and bring the fields onstream quickly, he said. The extendable draft platform (EDP) is a self-installing design made up of a floatable deck, stabilizing columns, and a heave plate connected to the bottom of the columns. The barge-type deck is designed to float the entire structure, including topsides, to the site. Once the EDP is onsite, the columns and heave plate are lowered and latched in the deck. Then, the deck is raised to the operating elevation by de-ballasting the columns.

"When it arrives on location, it is ready to go in a day or two," Murray said.

Another plus for the design, he said, is that fabrication is fairly simple. "The EDP doesn't require a very complex fabrication yard," Murray said.

The EDP has advantages over an FPSO, according to Murray. "Operators can drill, complete, perform workovers, and produce from the same platform," he said, adding that the EDP is able to come online more quickly than an FPSO as well.

"Technology is aimed at the economics," Murray said.

03-19-04

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