Method and apparatus for increasing floating platform buoyancy

Abstract

A floating platform for recovery of oil and gas from offshore oil and gas fields includes a hull having a portion located substantially below the water surface, and including a portion thereof which extends above the water surface. The platform is anchored to the seabed by one or more tendons secured to the base of the hull and the seabed. The playload capacity of the floating platform is increased without redesigning the structural design of the hull by attaching a column extension or mounting a detachable buoyancy module to the lower end of the hull for accomodating changing platform pay load requirements.

1 . A floating platform including a hull supporting one or more decks in a body of water above the water line, and anchor means securing the hull to the seabed below the water line, the improvement comprising buoyancy means secured to the lower end of said hull for increasing the buoyancy of the platform for supporting a greater payload or operating in a greater water depth without redesigning the structural design of said hull.  
     
     
         2 . The platform of  claim 1  wherein said buoyancy means comprises a column extension attached to the lower end of said hull.  
     
     
         3 . The platform of  claim 2  wherein said column extension includes plumbing for connection with the ballast system of said floating platform.  
     
     
         4 . The platform of  claim 1  wherein said buoyancy means comprises at least one buoyancy module mounted to the lower end of said hull.  
     
     
         5 . The platform of  claim 4  including one or more connectors mounted on the periphery of the lower end of said hull and said buoyancy module for securing said module to said hull.  
     
     
         6 . The platform of  claim 4  wherein said connectors include cooperative connector means for releasably attaching said buoyancy module to said hull.  
     
     
         7 . The platform of  claim 2  wherein said column extension includes support means on the peripheral surface thereof for supporting one or more risers or flow lines connected to said floating platform.  
     
     
         8 . The platform of  claim 4  wherein said buoyancy module includes support means on the peripheral surface thereof for supporting one or more risers or flow lines connected to said floating platform.  
     
     
         9 . A method for increasing the payload capacity of a floating platform without redesigning the structural design of the hull of said platform, the method including the step of attaching an extension on the lower end of the hull of said platform.  
     
     
         10 . A method of increasing the payload capacity of a floating platform without redesigning the structural design of the hull of said platform, the method including the step of mounting a detachable buoyancy module on the lower end of the hull of said platform.