Method and system for manipulating an object located underwater

Information

  • Patent Grant
  • 6443660
  • Patent Number
    6,443,660
  • Date Filed
    Monday, November 27, 2000
    24 years ago
  • Date Issued
    Tuesday, September 3, 2002
    22 years ago
Abstract
An apparatus for manipulating an object located proximate an underwater floor is disclosed, in a preferred embodiment comprising a foundation implantable in the underwater floor; a lifting frame extending between the foundation; and a multiplicity of slings mounted adjacent to each other and attached to the lifting frame such that each of the slings is suspended in a cradle-like configuration from the lifting frame. Each of the slings further comprises a top surface facing away from the underwater floor and a padding material mounted proximate the top surface of each sling. The foundation may further comprise suction piles. A monitoring system comprising instrumentation may also be used to aid in guiding the load transfer of the object from the floor to the lifting frame. A method of lifting is described comprising lowering and securing the foundation into the underwater floor proximate the object to be retrieved, positioning the lifting frame proximate the object to be retrieved, installation of containment material, securing lifting frame ends onto the foundation, securing each end of each sling onto the lifting frame as well as positioning each sling under the object to be retrieved, tensioning each sling, and then raising the object by raising the lifting frame.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to manipulating objects located proximate an underwater floor. By way of further particularity, the present invention relates to an apparatus and method of using the apparatus for salvage and recovery of fully or partially submerged objects. By way of further particularity, the present invention relates to an apparatus and method for recovering fully or partially submerged objects from an underwater floor such as a seabed, lake, river, or marsh, especially in operations having delicate or difficult archeological retrieval characteristics.




2. Description of the Related Art




There are numerous patents in the field of underwater salvage and recovery systems and methods. As summarized below, these patents neither teach nor suggest use of a support foundation implanted or otherwise imbedded in an underwater floor such as a seabed or having a lifting frame with a series of slings that are suspended from the lifting frame in a cradle-like configuration.




U.S. Pat. No. 4,658,745 issued to Beucher discloses a salvage apparatus that includes a drum container. The salvage apparatus


10


is taken by a diver from a surface craft to an object to be retrieved


12


from the ocean floor.




U.S. Pat. No. 5,820,109 issued to Jermyn, et al. discloses a salvage apparatus that includes a lift system


10


. The lift system


10


has a flotation unit


18


having connection means to provide appropriate points on a harness


20


to provide for attachment of tethers. Means for attaching to and lifting underwater salvage items are disclosed.




U.S. Pat. No. 4,319,372 issued to Tausig discloses a salvage apparatus for delivering a heavy cable from the ocean's surface to an extended depth for attachment to an object to be salvaged. The apparatus


10


includes a buoyancy float


12


formed of a syntactic foam. The buoyancy float


12


further has a central longitudinal aperture


18


extended from a rounded top of the buoyancy float


12


to a substantially flat bottom of the buoyancy float


12


.




U.S. Pat. No. 5,551,801 issued to Gallaher, et al. discloses a hyjack platform with compensated dynamic response. An offshore platform structure is disclosed for temporarily using a jack-up rig. Pile sleeves


20


support a truss assembly, e.g. surface tower


28


. See also U.S. Pat. No. 5,741,089 issued to Gallaher, et al. and U.S. Pat. No. 5,593,250 issued to Smith, et al., each of which also disclose hyjack platforms and methods of use.




U.S. Pat. No. 5,655,938 issued to Huguenun, et al. discloses a variable buoyancy float/ballast system having a float/ballast assembly


23


. A lower ballast portion


26


carries a fixed but adjustable ballast in modular increments. A floatation chamber


27


is attached to float/ballast assembly


23


. When chamber


27


is flooded, float/ballast assembly


23


sinks, and when filled with air, float/ballast assembly


23


rises. One or more mooring lines attach to float/ballast assembly


23


and to an object to be raised such as cage


20


.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a plan view of a representative configuration of the salvage system of the present invention.





FIG. 2

is a plan perspective view of a representative lifting frame.





FIG. 3

is a plan perspective view of a representative sling.





FIG. 4

is a plan perspective view of a representative lifting frame being lowered into place over a partially embedded object to be retrieved.





FIG. 5

is a plan perspective view of a representative sling being positioned under a partially embedded object to be retrieved.





FIG. 6

is a plan perspective view of a representative sling being attached to a representative lifting frame.





FIG. 7

is a plan perspective view showing buffer bags being inflated.





FIG. 8

is a plan perspective view showing a plurality of slings deployed under an object as the object is being lifted.











DETAILED DESCRIPTION




The present invention relates to an apparatus for use in recovering objects such as objects that might be fully or partially submerged in a body of water such as a seabed or marsh, especially in operations having delicate or difficult archeological retrieval characteristics and/or where objects are fully or partially embedded into a floor of the body of water.




Referring now to

FIG. 1

, the present invention's system comprises foundation


10


, lifting frame


20


, and rigging system


30


.




Foundation


10


may be constructed from any material appropriate for use underwater. It is understood that the underwater environment may be fresh water, salt water, brackish water, marshes, or any combination thereof and that each underwater environment may present differing turbulence or tidal features. As opposed to the prior art use of similar foundations to support a tensile load such as to anchor a floating oil platform, foundation


10


of the present invention supports a compressive load.




Foundation


10


supports lifting frame


20


and comprises bearing table


18


as well as outer wall


15


and top surface


16


defining cavity


17


that is at least partially implantable into floor


100


where floor


100


is a seabed, lake floor, river bed, or the like. Bearing table


18


may be adjustable such as to allow for variations in position of lifting frame


20


into position onto foundation


10


.




In the preferred embodiment, foundation


10


comprises a pair of suction piles


12


, similar to those used in oilfield operations as will be familiar to those of ordinary skill in offshore platform construction arts. Examples of similar suction piles may be seen in U.S. Pat. No. 4,432,671 issued to Westra et al. and U.S. Pat. No. 4,318,641 issued to Hogervorst. Outer wall


15


of suction pile


12


provides for skin friction load bearing and top surface


16


may bear directly on floor


100


. Suction piles


12


are positioned to a predetermined position on floor


100


proximate object


110


. In the preferred embodiment, suction piles


12


comprise welded A36 steel, but, by way of example and not limitation, can further comprise general purpose mild steel or any other material capable of supporting lifting frame


20


and its loads. The actual dimensions of suction piles


12


may vary depending on the actual or presumed characteristics of floor


100


including the depth of floor


100


, as will be familiar to those of ordinary skill in the underwater construction arts.




Alternatively, foundation


10


may be a sufficiently supportive floor


100


. Suction pile


12


is preferred when floor


100


is of unknown load bearing ability. However, if floor


100


is sufficiently firm, a “mud mat” such as a concrete mat (not shown in the figures) may be used to more or less conform to or lay flat on floor


100


to support the weight of lifting frame


20


and object


110


. Mud mats may comprise steel, concrete, wood, or any combination of materials that sinks and can provide sufficient support for lifting frame


20


and object


110


.




Alternatively, foundation


10


may be a sufficiently supportive floor


100


. Suction pile


12


is preferred when floor


100


is of unknown load bearing ability. However, if floor


100


is sufficiently firm, a “mud mat,” generally referred to by the numeral “


11


,” such as a concrete mat


11


may be used to more or less conform to or lay flat on floor


100


to support the weight of lifting frame


20


and object


110


. Mud mats


11


may comprise steel, concrete, wood, or any combination of materials that sinks and can provide sufficient support for lifting frame


20


and object


110


.




In the preferred embodiment, submersible hydraulic pump


51


has an approximately 4″ diameter inlet pipe mated to an approximately 4″ pipe stub welded in through top surface


16


of suction pile


12


. Alternatively, submersible hydraulic pump


51


may be electrically or pneumatically actuated, and alternatively may be located on a deck of vessel


120


, a platform , or another suitable structure such as a river bank, providing that pump


51


has sufficient power to create a differential pressure needed to drive suction pile


12


into floor


100


.




Lifting frame


20


is a structure to be supported by foundation


10


. Lifting frame


20


may be configured as a truss or any other appropriate structure, all of which will be readily understood by those of ordinary skill in the structural design arts. In a preferred embodiment, lifting frame


20


is a light weight truss whose length is at least equal to that of object


110


.




In the preferred embodiment, lifting frame


20


further comprises a first longitudinal member


21


and a second longitudinal member


22


where longitudinal members


21


,


22


are spaced apart a distance greater than or equal to the width of object


110


. However, lifting frame


20


may comprise a single longitudinal member such as longitudinal member


21


or have any predetermined shape capable of supporting object


110


during lifting, by way of example and not limitation such as a substantially rectangular shape.




Lifting frame


20


may be made of any material appropriate to withstand the fluid and chemical environment into which lifting frame


20


may be submerged. In a preferred embodiment for salt-water use, lifting frame


20


comprises a suitable grade of steel such as 500 grade steel which has greater material strength that the material used for suction piles


12


. In alternative embodiments, lifting frame


20


may comprise any material appropriate in light of factors relevant to object


110


and its environment, by way of example and not limitation including the weight and condition of object


110


, the distance between foundation


10


components, the number and location of rigging connections between object


110


and lifting frame


20


, and water current forces.




Once lowered into place, ends


21




a


,


22




a


,


21




b


, and


22




b


of lifting frame


20


are supported on foundation


10


and lifting frame


20


fixed in place such as by securing ends


21




a


,


22




a


,


21




b


, and


22




b


. Alternatively, securing ends


21




a


,


22




a


,


21




b


, and


22




b


may rest on foundation


10


, secured by the weight of lifting frame


20


onto foundation


10


. In a currently preferred embodiment, lifting frame


20


is supported by adjustable bearing table


18


to account for foundation misalignment of plumb, altitude, placement, and/or rotation, and is chained to foundation


10


to secure it to foundation


10


. Alternatively, lifting frame


20


may further comprise bolt holes located within or proximate to lifting frame


20


bearing seats (not shown in the figures) that land on foundation


10


on bearing table


18


. Preconfigured bolt holes may exist in bearing table


18


to receive one or more through bolts where the through bolts also pass through lifting frame


20


bolt holes. In an alternative embodiment, bolt holes may be drilled or otherwise created in mounting table


18


to receive through bolts. As will be apparent to those of ordinary skill in the construction arts, lifting frame


20


may also be secured to foundation


10


by chains, bolts, locking latches, pin-and-box, ball-and-socket, or any other appropriate connectors.




Sling securing ends, generally referred to by the numeral “


32


” in the figures and shown as sling securing ends


32




a


and


32




b


in

FIG. 1

, are disposed about lifting frame


20


. In a preferred embodiment, sling securing ends


32


connect padeyes


27


running the length of lifting frame


20


. In a currently preferred embodiment, padeyes


27


are secured to lifting frame


20


as by welding or other securing means, all of which will be understood by those of ordinary skill in the fabrication arts.




Rigging system


30


comprises at least one sling


34


secured to lifting frame


20


using sling ends


32


such as by attachment to padeyes


27


. In a currently preferred embodiment, sling


34


comprises a multiplicity of slings


34


mounted adjacent to each other where each of slings


34


has a first end


34




a


attached to first longitudinal member


21


at sling securing end


32




a


and a second end


34




b


attached to second longitudinal member


22


at sling securing end


32




b


, such that, once attached to lifting frame


20


, each of slings


34


is suspended in a cradle-like configuration from lifting frame


20


.




Referring now to

FIG. 2

, lifting frame


20


may be configured as a truss with a plurality of longitudinal members


21


,


22


, a plurality of support legs


25


, and a plurality of ribs


26


. If floor


100


is sufficiently supportive, foundation


10


maybe eliminated and lifting frame


20


secured directly onto floor


100


or other support structures such as mud mats such as by support legs


25


. In situations, length of support legs


25


may be adjustable such as to account for irregularities in floor


100


.




In alternative embodiments, one or more measurement gauges such as strain gauges, tension gauges, sonic, and/or linear variable displacement transducers or “LVDTs”


42


may also be present. In a presently preferred embodiment, LVDT


42


is a tubular further comprising rod


42




a


(not shown in the figures) movably mounted within LVDT


42


. Rod


42




a


may contact object


110


such as by gravity or other attaching means. The movement of rod


42




a


within LVDT


42


induces a current within a sensing loop such as by a disturbance in a magnetic field. Current may then be passed to monitoring equipment to sense the current. In an alternative embodiment, rod


42




a


may be calibrated and monitored visually.




Referring now to

FIG. 3

, each sling


34


further comprises top surface


35


facing away from floor


100


. Slings


34


may further comprise buffering and securing components, including by way of example and not limitation buffer bags


36


such as nylon buffer bags located proximate top surface


35


, tensioning hardware such as turnbuckles


32


and chains


37


, and monitoring instrumentation


41


(not shown in the figures) suitable to aid in guiding the load transfer of object


110


from floor


100


to lifting frame


20


. Buffer bag


36


provides a cushioning contact area that will conform to an surface geometry of object


110


.




In a preferred embodiment, slings


34


comprise nylon slings that range from around 8″ to around 18″, but the actual dimensions of slings


34


may vary depending on the actual object


110


to be retrieved. Slings


34


may further comprise hole pattern


31


for attaching buffer bags


36


. Bag fasteners


33


(not shown in the figures) may be used to attach buffer bags


36


to sling


34


by any appropriate means, such as rope, cord, monofilament lines, fasteners, hooks and loops, small lines, cable ties, and the like, or any combination thereof.




“Secondary” slings


34


may be used to minimize stress in object


110


and provide general flexibility in securing object


110


. Secondary slings


34


are distinguished from other slings


34


by usage. By way of example and not limitation, where object


110


has structural characteristics indicating points of weakness along object


110


, secondary slings


34


may be used as a precaution to reduce the stress induced in object


110


. Secondary slings


34


may be attached to lifting frame


20


such as at sling ends


34




a


,


34




b


or to other slings


34


. Thus, in situations where object


110


could have compromised or questionable structural integrity, and/or disarticulated or fractured features, secondary slings


34


may be used to provide additional, ancillary support as opposed to main lifting support of other slings


34


.




In the presently preferred embodiment, a single buffer bag


36


comprising a nylon mesh adapted to receive and retain a fluid therein is disposed proximate top surface


35


. Each buffer bag


36


may be independent of any other buffer bag


36


and each may be independently fillable with fluid. In an alternative embodiment, buffer bags


36


may further comprise injector ports adapted to receive and retain fluids. Further, the present invention can be satisfied with a single buffer bag


36


whether independent of or integrated into sling


34


, a plurality of buffer bags


36


whether independent of or integrated into sling


34


, or any combination thereof. In a currently envisioned alternative embodiment, buffer bags


36


may be preformed out of a material such as out of a neoprene material to a desired conforming shape before attaching buffer bags


36


to slings


34


.




A tensioning system for each sling


34


may be present as well, and may further comprise turnbuckles


32


, chains


37


, load cells


41


, and vertical measurement gauges (“LVDTs”)


42


(shown in FIG.


2


). In an alternative embodiment, the tensioning system may employee ratchet type tensioners, chain binders, and cable slings, as will be familiar to those in the construction arts. Load cells


41


and LVDTs


42


may be further connected by an appropriate signaling means such as a wire or optical pathway


39


to instrumentation such as data recording and display systems (not shown in the figures) located at vessel


120


or a surface such as a river bank. Pathway


39


may thus be used to relay information about tension in sling


34


and other monitored data to data recording and display systems such as by way of example and not limitation to general purpose computers, special purpose computers, digital readout devices, analog readout devices, or the like, or any combination thereof.




A tensioning system for each sling


34


may be present as well, and may further comprise turnbuckles


32


, chains


37


, load cells


41


, and vertical measurement gauges (“LVDTs”)


42


(shown in FIG.


2


). In an alternative embodiment, the tensioning system may employee ratchet type tensioners, chain binders, and cable slings, as will be familiar to those in the construction arts. Load cells


41


and LVDTs


42


may be further connected by an appropriate signaling means such as a wire or optical pathway


39


to instrumentation such as data recording and display systems


200


(

FIG. 1

) located at vessel


120


or a surface such as a river bank. Pathway


39


may thus be used to relay information about tension in sling


34


and other monitored data to data recording and display systems such as by way of example and not limitation to general purpose computers, special purpose computers, digital readout devices, analog readout devices, or the like, or any combination thereof.




Lifting frame


20


is then positioned into place onto foundation


10


proximate object


110


such as by lowering it from vessel


120


, and lifting frame ends


22


are then secured onto foundation


10


. In a preferred embodiment, lifting frame ends


22


are secured such as by chains secured through padeyes


27


that may be present in bearing table


18


. When secured onto foundation


10


, lifting frame


20


is positioned in a predetermined position proximate object


110


suitable for lifting object


110


in support structure.




In an alternative embodiment, foundation


10


may be preassembled with lifting frame


20


before lowering foundation


10


and lifting frame into the water.




Referring now to FIG.


5


and

FIG. 6

, once lifting frame


20


is secured onto foundation


10


, each sling


34


to be used during the salvage operation is attached to first longitudinal member


21


at sling securing end


32




a


and then draped or otherwise positioned under object


110


. Floor


100


material may be partially excavated from near and/or under object


110


to facilitate draping or otherwise positioning sling


34


under object


110


. Second end


34




b


of sling


34


is then retrieved from under object


110


and then attached to second longitudinal member


22


at sling securing end


32




b


, such that each of slings


34


is suspended in a cradle-like configuration from lifting frame


20


under object


110


. In a currently preferred embodiment, excavation can occur in a progressive manner, such that the load of object


110


is transferred incrementally. As each incremental tension step occurs, additional excavation may then take place.




Referring now to

FIG. 7

, if not already attached, buffer bags


36


are attached such as by lacing to each sling


34


using hole patterns


31


and bag fasteners


33


. Alternatively, buffer bags


36


may have already been placed onto sling


34


or sling


34


may be integral with buffer bags


36


. Buffer bags


36


are then injected with a predetermined fluid, by way of example and not limitation directly through an outer surface of buffer bag


36


or through an injector port. In the preferred embodiment, the fluid used is a two part industrial polyurethane foam commonly used in the insulation and refrigeration industry. One such foam is FROTH-PAK(TM), produced by Flexible Products, 1007 Industrial Park Drive, Marietta, Ga. 30062. It is anticipated that standard foam hoses and foam injection guns can be used to inject the fluid into buffer bags


36


, and that manual as well as mechanized or other pressurized means such as pressure tanks, compressors, and the like may be used. Further, although a single buffer bag


36


may be used, a plurality of buffer bags


36


may be used to better conform to the shape of object


110


.




If a foam is used as in the preferred embodiment, the foam may be inserted into buffer bag


36


by inserting a nozzle tip of the foam injection gun directly into buffer bags


36


and injecting foam until each buffer bag


36


conforms to object


110


or otherwise appears full to the person injecting the foam. In an alternative embodiment, buffer bag


36


further comprises one or more injector ports into which the nozzle tip may be inserted. The foam may then be allowed to harden.




Referring now to

FIG. 8

, once each sling


34


is positioned and buffer bags


36


filled, each sling


34


is tensioned to transfer the weight of object


110


to lifting frame


20


and foundation


10


. Numerous means of tensioning may be used as will be familiar to those of ordinary skill in the structural arts, including by way of example and not limitation use of turnbuckles


32


attached to one or more ends of sling


34


, or rachet type tensioners comprising straps secured on one side with hooks, passed under buffer bags


36


, and threaded into spools in a support bracket. The spools may be turned such as with a lever or other extension to tighten the straps against the load to hold it in place.




Slings


34


are tensioned using the tensioning system. Tension may be estimated initially or the tensioning system may be used to adjust the tension for each sling


34


. Once object


110


is secured, such as when all slings


34


are tensioned, lifting frame


20


is released from foundation


10


, if secured to foundation


20


, and lifting frame


20


is then lifted, along with object


110


. As object


110


is lifted, tensioning may be further adjusted, either manually, automatically, or a combination thereof. Once fully retrieved, lifting frame


20


may be secured onto a surface such as a ship or barge deck by using support legs


25


. Alternatively, lifting frame


20


may be positioned onto a cradle on a surface such as a ship or barge deck where the cradle is preconfigured to accept lifting frame


20


and object


110


suspended in slings


34


.




In a preferred embodiment, LVDTs


42


allow monitoring of bending of object


110


. Thus, during tensioning and/or lifting, if monitors determined that the bending is excessive, LVDTs


42


will indicate where the tensioning needs to be adjusted. Divers may be instructed on tension adjustments during the lifting from monitors such as by radio, direct linkage, or other means as are well known in the diving arts. In addition, tension adjustments may be made automatically through automated means using data gathered by a data recording and display system (not shown in the figures). It is understood that as used herein above, “monitors” may be human beings, automated systems, or any combination thereof.




Suction piles


12


may be retrieved after use by reversing the installation procedural steps.




In addition to using the apparatus and method of the present invention for salvage and retrieval operations, the present invention may also have use in other underwater endeavors. By way of example and not limitation, the current example can be used to manipulate pipeline equipment such as underwater tubulars, underwater telephony cables, valve assemblies, other underwater structures such as pumps or electro-mechanical machinery, and the like, or any combination thereof. Such usage may also include manipulation of underwater objects for installation, maintenance, and repair operations as well as salvage and/or removal. These are by way of example and illustration only as the scope of the invention is described by the claims herein.




It will be understood that various changes in the details, materials, and arrangements of the parts which have been described and illustrated above in order to explain the nature of this invention may be made by those skilled in the art without departing from the principle and scope of the invention as recited in the following claims.



Claims
  • 1. A system for manipulating an object located underwater, comprising:a) a foundation implantable in an underwater floor; b) a lifting frame having a first end and a second end, each adapted for mounting on the foundation, the lifting frame further comprising a first longitudinal member and a second longitudinal member extending between the first and second ends, the longitudinal members being spaced apart a predetermined distance; c) a multiplicity of slings mounted adjacent to each other, each of the slings having a first end attachable to the first longitudinal member and further having a second end attachable to the second longitudinal member, such that, when attached to the first longitudinal member and second longitudinal member, each of the slings is suspended in a cradle-shaped configuration from the lifting frame, each of the slings further comprising a top surface facing away from the underwater floor; and d) a padding material mounted proximate the top surface of each sling.
  • 2. The system of claim 1 wherein the lifting frame further comprises a plurality of support legs and support ribs.
  • 3. The system of claim 1 wherein the spacing of a predetermined distance of the longitudinal members is at least equal to a width of the object sought to be manipulated.
  • 4. The system of claim 1 wherein the padding material comprises at least one buffer bag adapted to receive a fluid.
  • 5. The system of claim 4 wherein the fluid is an expansive foam.
  • 6. The system of claim 1 wherein the foundation further comprises:a) a first suction pile implantable in the underwater floor, the first suction pile having an outer wall and a top surface defining an interior void that is at least partially implanted into the underwater floor; and b) a second suction pile implantable in the underwater floor, the second suction pile having an outer wall and a top surface defining an interior void that is at least partially implanted into the underwater floor, the second suction pile being positioned a predetermined distance from the first suction pile; wherein the lifting frame extends between the first and second suction piles, the lifting frame having a first end adapted for mounting on the first suction pile and further having a second end adapted for mounting on the second suction pile; and the predetermined distance between the first and second suction piles exceeds a length of the object sought to be recovered from the underwater floor.
  • 7. The system of claim 6 further comprising a submersible hydraulic pump operatively connected to a hydraulic power unit through at least one fluid hose, the hydraulic pump further operatively connected to an inlet in at least one of the suction piles, whereby the hydraulic pump creates a differential pressure needed to drive the suction pile into the underwater floor.
  • 8. The system of claim 6 wherein the first suction pile further comprises a bearing table disposed proximate the top surface of the first suction pile, and the second suction pile further comprises a bearing table disposed proximate the top surface of the second suction pile, wherein each of the bearing tables is adapted to receive either the first end or the second end of the lifting frame.
  • 9. The system of claim 1 further comprising a tensioning system, the tensioning system comprising:a) a tension adjuster disposed between each sling and the lifting frame; b) a load cell operatively connected to a sling; c) a vertical measurement gauge operatively in communication with the object; d) a pathway; and e) a data recording and display system operatively connected to the pathway; f) wherein the pathway is further operatively connected to and conveys data between at least one of the load cell or the vertical measurement gauge to the data recording and display system.
  • 10. A system for lifting an object disposed proximate an underwater floor, where the density of the underwater floor can support a compressive load, the system comprising:a) a lifting frame extending between a first foundation portion and a second foundation portion, the lifting frame having a first end adapted for mounting on the underwater floor and further having a second end adapted for mounting on the underwater floor, the lifting frame further comprising at least one object lifting support member; b) a multiplicity of slings mounted adjacent to each other, each of the slings further comprising: i) a first end attached to the object lifting support member; ii) a second end attached to the object lifting support member; iii) a top surface facing away from the underwater floor; and iv) a padding material mounted proximate the top surface of each sling. c) wherein i) each of the slings is suspended in a cradle-shaped configuration from the lifting frame and ii) the padding material is disposed intermediate the object and the sling.
  • 11. The system of claim 10 wherein the object lifting support member further comprises a first longitudinal member and a second longitudinal member extending between the first and second ends, the longitudinal members being spaced apart a distance greater than or equal to the width of the object sought to be recovered.
  • 12. The system of claim 10 further comprising at least one mud mat deployable on the underwater floor, the mud mat being capable of supporting the lifting frame during at least an initial lifting of the object.
  • 13. A method of manipulating an object that is at least partially underwater with an apparatus comprising a lifting frame comprising a first longitudinal member, a second longitudinal member, and first and second lifting frame ends adapted for mounting on a foundation; and at least one sling adapted to receive padding material; the method comprising:a) positioning the lifting frame proximate an object to be retrieved from an underwater floor; b) securing one end of the at least one sling onto the first longitudinal member of the lifting frame; c) positioning the at least one sling under the object to be retrieved, the at least one sling further positioned adjacent to at least one other sling; d) retrieving a free end of the least one sling from under the object to be retrieved; e) securing the free end of the at least one sling onto the second longitudinal member of the lifting frame; f) disposing padding material intermediate the object and the at least one sling; g) conforming a predetermined amount of padding material to the object; h) tensioning the at least one sling; and i) raising the object by raising the lifting frame.
  • 14. The method of claim 13 for a system further comprising a foundation, the method further comprising:a) positioning the foundation onto the underwater floor proximate the object to be retrieved before positioning the lifting frame proximate an object to be retrieved from the underwater floor; b) securing the foundation into the underwater floor before positioning the lifting frame proximate the object to be retrieved from the underwater floor; and c) securing the lifting frame to the foundation after positioning the lifting frame proximate the object to be retrieved from the underwater floor.
  • 15. The method of claim 13 for a system further comprising a plurality of suction piles, each suction pile having a top surface and an outer wall defining an inner cavity, the method further comprising:a) lowering each of the suction piles to a predetermined position proximate the object to be retrieved; b) connecting a submersible hydraulic pump powered by hydraulic fluid pumped to it from a separate hydraulic power unit to a fluid supply hose and fluid return hose; c) connecting the fluid supply hose and the fluid return hose to a predetermined number of the suction piles; d) using the pump to remove the water from within the suction pile cavity, thereby creating a lower pressure inside the suction pile than outside the pile; e) using the greater pressure outside the suction pile to create a force on the top surface of the suction pile to push the suction pile into the floor; and f) pumping water from inside the suction pile into water surrounding the suction pile until the suction pile is embedded in the floor to a predetermined depth.
  • 16. The method of claim 15 for suctions piles further comprising bearing tables mounted proximate the top surface of at least one suction pile and adapted to receive an end of the lifting frame, the method further comprising securing the end of the lifting frame into an adapter portion of the bearing table adapted for receiving the end of the lifting frame.
  • 17. The method of claim 13 wherein the padding material comprises a first predetermined number of buffer bags adapted to receive fluid, the method further comprising injecting a predetermined fluid into a second predetermined number of the buffer bags until the fluid attains a predetermined volume.
  • 18. The method of claim 17 wherein the fluid is a foam fluid that hardens, the method further comprising allowing the foam fluid to harden in the second predetermined number of buffer bags prior to tension each sling.
  • 19. The method of claim 13 for an apparatus further comprising a tension monitoring system, the method further comprising:a) continually monitoring tension in at the least one sling; and b) adjusting the tension in the at least one sling prior to and/or during the raising of the object to achieve a desired tension.
  • 20. The method of claim 13, further comprising:a) positioning at least one mud mat proximate the object to be retrieved; b) positioning the lifting frame proximate the object to be retrieved; and c) securing the lifting frame onto the mud mat.
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