Patent ID: 7628206
Filing Date: 2009-12-08
Classification: E21B

Abstract:
1. An apparatus to communicate with a plurality of subsea wells located at a depth from the surface of a body of water, the apparatus comprising: a floating platform including a dry tree apparatus configured to communicate with and service the subsea wells; and a plurality of variable tension risers comprising a negatively buoyant region, a positively buoyant region, and a neutrally buoyant region between the negatively and positively buoyant regions, and configured to extend from the wells to the floating platform, wherein the variable tension risers are disposed between the well and the floating platform; at least one a linking member connected along the plurality of variable tension risers below the platform to maintain radial spacing of the plurality of variable tension risers and within the negatively buoyant region to interconnect the plurality of variable tension risers to restrict relative lateral movements and allow axial movement of the variable tension risers relative to each other variable tension risers; wherein the negatively buoyant region hangs below the floating platform and exhibits positive tension on the floating platform, the neutrally buoyant region is located between the negatively and positively buoyant regions and characterized by a curved geometry configured to traverse a lateral offset of at least 300 feet between the floating platform and the subsea well, and the positively buoyant region is positioned above the subsea well and exhibits positive tension on the well.