The recent hurricanes that battered the offshore facilities in the Gulf of Mexico have prompted many operators and drilling contractors to rethink the way their drilling risers are designed for disconnection and retrieval before the hurricane arrives.

When drilling in very deep water depths, retrieval of the drilling riser is time consuming and tedious; and in emergency situations like the imminent arrival of a hurricane, the drilling rigs risk not being able to recover the drilling risers in time before the evacuation of personnel or sailing for shelters, with potentially devastating consequences.

A solution to overcome this concern is to modify the existing drilling riser to make it disconnectable closer to the surface and leave the long riser string below (and subsea BOP) in a safe and freestanding mode to survive the storm.

This paper presents the feasibility of such a modification, and describes the simple buoyancy system and additional components required. The study also outlines hydrodynamic and structural analyses required to demonstrate integrity of the freestanding drilling riser.

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