Heavier, bigger, deeper
Upstream, June 6
Just like the scene off Brazil not so many years ago, currently the US Gulf of Mexico is the region that is racking up the world records and showcasing a steady stream of deep-water technological advances.
The region continues to make the spar platform its own, with half a dozen such structures right now moving along the path to production start-up, although the design has still to break through anywhere else in the world.
The deepest ever spar -- Devils Tower (pictured here under construction) -- is due to move out from Pascagoula for installation in 5610 feet of water just as soon as problems surrounding its suction foundation piles have been resolved.
In the space of the ensuing 12 months, another five spars will follow.
For sheer size, BP's Holstein takes top position, with BP's other spar, Mad Dog, in the next slot.
Among the other three is the first of a new variation on the spar theme in the shape of Kerr McGee's Red Hawk unit.
Also for the first time, lightweight polyester rope has broken through as a replacement for steel wire in the mooring system of two of these upcoming spars -- Mad Dog and Red Hawk.
Tension-leg platforms are in the news as well, and setting records in the region. The three Ms of Matterhorn, Marco Polo and Magnolia are steadily pushing the envelope for this type of platform.
Matterhorn moves out to the field this month. It is twice the size of any of the three previous TLPs from contractor Atlantia, and its first to support dry trees.
Later in the year, the Modec-designed Marco Polo TLP will follow, with the hull due to sail away from Samsung's yard in Korea this month. For a short while this platform will hold the record as the world's deepest TLP, tied down in 4300 feet of water.
However, around nine months later, that record will fall to Magnolia's 4700 feet when this ABB-designed platform starts up for ConocoPhillips. Steel tube is still being used for the tendons here, albeit taking a stepped-diameter approach. But lightweight composite materials are a strong likelihood for any future TLP in this sort of depth.
However, the platform type making the biggest comeback for production in the Gulf right now is the semi-submersible. A semi is at the centre of three of the most significant projects currently under way in the US Gulf.
First of these is Na Kika, which should move out to the field this month. The platform will not just be in extremely deep water -- 6200 feet -- but will also support sizeable facilities, able to process 100,000 barrels per day of oil, and gas to the equivalent of another two-thirds of that.
Then, at intervals of around 18 months, Na Kika will be followed into the Gulf first by BP's mighty Thunder Horse semi, then by Atlantis, both designed by GVA.
Able to process 250,000 bpd of oil, Thunder Horse will have by far and away the biggest production capacity of any US Gulf platform. |
