Submersible offshore positionable frame

Abstract

A submersible offshore jack-up frame comprises a base and at least four legs, wherein said base is positionable along said legs, so that said base may be moved from a first position wherein said base is transportable on the deck of a surface vessel such as a barge, to a second position wherein said base is above a water surface when supported by said legs. The base may be elevated above the deck of the barge when supported by said legs. The base is also positionable on said legs so as to be submerged below the water surface to allow a barge to be positioned above the base, and then elevated to support the barge above sea level.

1 - 8 . (canceled) 
     
     
         9 . A jack-up structure for elevating a barge above water level which comprises:
 a) a non- buoyant, barge-engaging base;   b) a plurality of legs;   c) a drive mechanism;   said base engaged with said legs such that the base is movable, via the drive mechanism, vertically along said legs, from a first position, (which is selected from the group consisting of at water level and under water level) to a second position elevated above water level; said structure having means i) to removably engage the barge and the base at the first position ii) to secure barge on the base for movement to the second position; ii) to move base (carrying the barge) between the first position and the second position.   
     
     
         10 . The structure of claim  1  wherein said base comprises a plurality of beams forming an array. 
     
     
         11 . The structure of claim  1  wherein said barge supports heavy equipment. 
     
     
         12 . The structure of claim  1  wherein said barge supports a crane. 
     
     
         13 . The structure of claim  1  further comprising a leg guard for each of said legs. 
     
     
         14 . The structure of claim  1  further comprising retractable stabilizing bars, said bars when extended being shaped to be received by ridges positioned on said barge, to prevent horizontal movement of said barge. 
     
     
         15 . The structure of claim  1  wherein said base is transportable on a deck of a surface vessel. 
     
     
         16 . The structure of claim  1  wherein the legs are extendable to engage a water bed. 
     
     
         17 . The structure of claim  1  comprising a barge locking mechanism to secure the barge in place on the base. 
     
     
         18 . The structure of claim  1  wherein the base is positionable and securable at any vertical point on said legs. 
     
     
         19 . The structure of claim  1  wherein the base is substantially solid and comprises at least one water-passing aperture. 
     
     
         20 . The structure of claim  1  wherein the barge is welded to the base. 
     
     
         21 . The structure of claim  1  comprising a base positioning apparatus. 
     
     
         22 . The structure of claim  1  comprising a generator. 
     
     
         23 . The structure of claim  1  comprising a hydraulic power pack. 
     
     
         24 . The structure of claim  1  comprising a jack and jack-locking means. 
     
     
         25 . The structure of claim  1  which is adapted to be carried, in water, under the barge. 
     
     
         26 . A system for off-shore construction which comprises:
 a) a jack-up structure for elevating a barge above water level which comprises:
 i) a non- buoyant, barge-engaging base; 
 ii) a plurality of legs; 
 said base engaged with said legs such that the base is movable, vertically along said legs, from a first position (which is selected from the group consisting of at water level and under water level) to a second position elevated above water level; said structure having means i) to removably engage the barge and the base at the first position ii) to secure barge on the base for movement to the second position; ii) to move base (carrying the barge) between the first position and the second position; 
   b) a plurality of supply barges which each, sequentially:
 i) with a payload, engage with the base at a first position; 
 ii) are elevated on the base to the second position; 
 ii) are relieved of the payload; 
 iv) are returned to the first position on the base; and 
 v) are disengaged from base. 
   
     
     
         27 . A buoyancy balanced barge comprising:
 a) a deck surface; and   b) a hull from which extends, under a water surface upon which the barge floats, a jack-up structure which comprises:
 i) a non- buoyant, barge-engaging base; and 
 ii) a plurality of legs. 
   
     
     
         28 . A buoyancy balanced barge wherein the deck comprises a payload. 
     
     
         29 . A method of conveying supplies to an off-shore site of a project which comprises:
 a) setting up at the off-shore site at least one jack-up structure for elevating a barge above water level which comprises:
 i) a non- buoyant, barge-engaging base; 
 ii) a plurality of legs; 
 said base engaged with said legs such that the base is movable, vertically along said legs, from a first position (which is selected from the group consisting of at water level and under water level) to a second position elevated above water level; said structure having means i) to removably engage the barge and the base at the first position ii) to secure barge on the base for movement to the second position; ii) to move base (carrying the barge) between the first position and the second position; 
   b) engaging a first payload carrying barge with the base in the first position such that the base is disposed upon the base;   c) securing the barge on the base;   d) elevating the base to the second position;   e) removing the payload;   f) lowering the base carrying the empty barge to the first position;   g) disengaging the barge from the base;   h) engaging a second payload carrying barge with the base in the first position such that the base is disposed upon the base; and   i) repeating steps c) to g) for the second payload carrying barge.   
     
     
         30 . The method of  claim 21  wherein the first position is under water level to facilitate placement of the barge on the base. 
     
     
         31 . The method of  claim 21  wherein said base comprises a plurality of beams forming an array. 
     
     
         32 . The method of  claim 21  wherein the structure comprises retractable stabilizing bars, said bars when extended being shaped to be received by ridges positioned on said barge, to prevent horizontal movement of said barge 
     
     
         33 . The method of  claim 21  wherein the structure comprises a barge locking mechanism to secure the barge in place on the base. 
     
     
         34 . The method of  claim 21  wherein the base is positionable and securable at any vertical point on said legs. 
     
     
         35 . A method of creating an off-shore platform for a project site which comprises:
 a) setting up at the site at least one jack-up structure for elevating a barge above water level which comprises:
 i) a non- buoyant, barge-engaging base; 
 ii) a plurality of legs; 
 said base engaged with said legs such that the base is movable, vertically along said legs, from a first position (which is selected from the group consisting of at water level and under water level) to a second position elevated above water level; said structure having means i) to removably engage the barge and the base at the first position ii) to secure barge on the base for movement to the second position; ii) to move base (carrying the barge) between the first position and the second position; 
   b) engaging a first payload carrying barge with the base in the first position such that the base is disposed upon the base;   c) securing the barge on the base;   d) elevating the base to the second position.   
     
     
         36 . The method of  claim 27  wherein the payload is heavy machinery and, at step e) such machinery is operated from the second position.