Abstract:
A method and apparatus for the salvage or installation of large multi-ton marine platform includes the use of usually two barges defining a base that can support a large multi-ton load. A lifting assembly is supported by the barge and forms a load transfer interface between the barge and the deck package. Each boom has a lifting end portion that fits a supplemental lifting frame attached to the platform. During removal of the platform from its underlying support (e.g. jacket), there are winches with cables that pull the barges together as the booms lift the supplemental lifting frame and the supported platform. The supplemental frame includes both horizontal and diagonal beams that interface with the platform to transmit load to the lower end of the platform.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Incorporated herein by reference are the following applications: 
     This application is a continuation PCT Application No. PCT/US98/17985; filed Aug. 31, 1998; and a provision of U.S. patent application Ser. No. 08/925,929, filed Sep. 08, 1997 now U.S. Pat. No. 6,039,506; which is a continuation of U.S. patent application Ser. No. 08/915,671, filed Aug. 21, 1997 abandoned; and a continuation of U.S. patent application Ser. No. 08/915,925, filed Aug. 21, 1997; U.S. patent application Ser. No. 08/925,929, filed Sep. 08, 1997; and a continuation-in-part of U.S. patent application Ser. No. 08/709,014, filed Sep. 06, 1996, which is a continuation-in-part of U.S. patent application Ser. No. 08/615,838, filed Mar. 14, 1996, which is a continuation-in-part of U.S. patent application Ser. No. 08/501,717, filed Jul. 12, 1995, now U.S. Pat. No. 5,607,260, which is a continuation-in-part of U.S. application Ser. No. 08/404,421 filed Mar. 15, 1995, now U.S. Pat. No. 5,609,441. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable 
     REFERENCE TO A “MICROFICHE APPENDIX” 
     Not applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to the salvage or installation of marine platforms and oil rigs that are supported upon a usually partially submerged jacket that extends between the seabed and the water surface. Even more particularly, the present invention relates to the use of a moving lifting assembly which is preferably barge supported that can remove and salvage or install very large marine platforms without the use of enormous lifting booms such as form a part of derrick barges, offshore cranes, and the like. The present invention features opposed short booms that are connected with an improved lifting arrangement to the lower end of the platform to be salvaged or installed. 
     2. General Background 
     In the offshore oil and gas industry, the search for oil and gas is often conducted in a marine environment. Sometimes the search takes place many miles offshore. Oil and gas well drilling takes place in many hundreds of feet of water depth. 
     The problem of drilling oil wells offshore and then producing these wells has been solved in part by the use of enormous fixed or floating platform structures with foundations that are mostly submerged, but usually extending a number of feet above the water surface. Upon this foundation (or “jacket”, tension leg platform (“TLP”), or SPAR, etc. referred to in the art) there is usually placed a very large prefabricated rig, deck, or platform. 
     The term “platform” as used herein should be understood to include any of a large variety of prefabricated structures that are placed in a marine environment, e.g., on an offshore foundation (e.g. jacket), to form a fixed or floating offshore platform. Thus, a “platform” can include, e.g. a drilling rig, a production platform, a crew quarters, living quarters, or the like. 
     A supporting jacket is usually a very large multi-chord base formed of multiple sections of structural tubing or pipe that are welded together. Such jackets have been used for a number of years for the purpose of supporting large deck platforms in an offshore environment. 
     The jacket or foundation is usually prefabricated on land in a fabrication yard, preferably adjacent to a navigable waterway. The completed jacket can be placed upon a large transport barge so that it can be moved to the drill site where it will be placed upon the ocean floor. As an example, an offshore jacket can be several hundred feet in length. The size of the jacket is of course a function of the depth of water in which the rig will be placed. A five hundred (500) foot water depth at the drill site (or production site) will require a jacket which is approximately 500-550 feet tall. The jacket is usually partially submerged, with only a small upper portion of the jacket extending slightly above the water surface. An offshore jacket as described and in its position on the seabed can be seen, for example, in the Blight, et al U.S. Patent No. 4,252,469 entitled “Method and Apparatus for installing integrated Deck Structure and Rapidly Separating Same from Supporting Barge Means.” Specifically, FIGS. 1,  2  and  3  of the Blight, et al patent show an offshore jacket on the seabed. 
     A small upper portion of the jacket extends above the water surface. This exposed portion of the jacket is the portion upon which the platform is placed and supported by. The upper portion of the jacket is usually equipped with a number of alignment devices which enhance the proper placement of the deck package on the jacket. Such alignment devices are referred to variously as stabbing eyes, sockets, or the like. The use of such alignment devices, sockets, or stabbing eyes can be seen in the Blight, et al U.S. Pat. Nos. 4,252,468 and U.S. Pat. No. 4,252,469 as well as in the Kansan U.S. Pat. No. 4,242,011. For purposes of background and reference, the Kansan patent U.S. Pat. No. 4,242,011 is incorporated herein by reference. The Blight, et al U.S. Pat. Nos. 4,252,469 and 4,252,468 are likewise each incorporated herein by reference. 
     Platforms or topsides can be extremely large and have correspondingly heavy weights. For example, it is not uncommon for a deck platform such as a drilling rig crew quarters, production platform or the like to be between five hundred and five thousand (500 and 5,000) tons gross weight. Topsides in excess of ten thousand (10,000) tons have been installed, and others that are being planned may weigh as much as thirty thousand (30,000) tons. Such enormous load values present significant problems in the placement of deck platforms on offshore jacket structures. First, the placement is done entirely in a marine environment. While the jacket can be laid on its side and/or floated into position, the platform is not a submersible structure, and must be generally supported in an upright condition above the water surface to prevent water damage to the many components that form a part of the drilling or production platform (such as electrical systems, wall constructions, and other portions that will be inhabited by individuals and used as oil and gas well drilling or production equipment). 
     After a number of years, offshore marine platforms can become obsolete and are abandoned. Once abandoned, these platforms become a hazard to navigation and must necessarily be removed. 
     The art has typically used enormous derrick barges for the purpose of removing abandoned platforms from their supporting jackets in an offshore environment. These derrick barges are large, rectangular barge structures with a high capacity lifting boom mounted at one end portion of the deck of the barge. The barge, for example might be three hundred to four hundred (300-400) feet in length, fifty to one hundred twenty (50-120) feet in width, and twenty-five to fifty (25-50) feet deep. These figures are exemplary. 
     A derrick barge might have a lifting capacity of for example, two thousand (2,000) tons. For very large structures such as for example, a five thousand (5,000) ton deck package, two derrick barges can be used, each supporting one side portion of the deck platform with a multi-line lift system supported by an enormous structural boom extending high into the air above the package during the lift. 
     While the use of such derrick barges has been successful in the removal of platforms and/or jackets through the years, such derrick barges are generally limited in their capacity to packages of two thousand (2,000) tons or less. Further, derrick barges of such an enormous capacity are extremely expensive to manufacture and operate. Many thousand of dollars per hour as a cost of using such a device is not uncommon. Although there are five (5) or six (6) derrick barges that can lift in excess of six thousand (6,000) tons, they are extremely costly and limited as to the water depth in which they can operate. 
     When very large loads of, for example six thousand—ten thousand (6,000-10,000) tons are involved, the limitation of the derrick barge usually prohibits such a lift. 
     In U.S. Pat. No. 4,714,382 issued to Jon Khachaturian there is disclosed a method and apparatus for the offshore installation of multi-ton prefabricated deck packages on partially submerged jacket foundations. The Khachaturian patent uses a variable dimensional truss assembly and is supported by the barge and forms a load transfer interface between the barge and the deck package. Upper and lower connections form attachments between the truss members and the deck package at upper and lower elevational positions on the deck package. The variable dimension truss includes at least one member of variable length, in the preferred embodiment being a winch powered cable that can be extended and retracted by winding and unwinding the winch. Alternate embodiments include the use of a hydraulic cylinder as an example. Other Khachaturian patents include U.S. Pat. Nos. 5,607,260; 5,609,441; 5,662,434; 5,800,093; and 5,975,807; each of which is hereby incorporated herein by reference. 
     An earlier patent, U.S. Pat. No. 2,598,088 issued to H. A. Wilson entitled “Offshore Platform Structure and Method of Erecting Same” discusses the placement of drilling structure with a barge wherein the legs of the drilling structure are placed while the drilling structure is supported by two barges. The Wilson device does note use truss-like lifting assemblies having variable length portions which are placed generally on opposite sides of the deck package. Rather, Wilson relates to a platform which is floated in place and the support legs are then placed under the floating platform. Thus, in the Wilson reference, an in-place underlying supporting jacket is not contemplated. 
     The Natvig, et al U.S. Pat. No. 3,977,346 discusses a method of placing a deck structure upon a building site such as a pier. The method includes the pre-assembly of a deck structure upon a base structure on land so that the deck structure extends outwardly over a body of water. Floating barges are provided for supporting the deck structure outwardly of the building site. The deck structure is then transferred to the supportive base structure by means of barges. The Natvig reference uses two barges which are placed on opposite sides of a platform with pedestal type fixed supports forming a load transfer member between the barges and the platform. However, the fixed pedestal of Natvig is unlike the truss-like lifting arrangement of applicant which include movable portions at least one of which can be of a variable length. 
     U.S. Pat. No. 4,249,618, issued to Jacques E. Lamy, discloses a method of working an underwater deposit comprising the following stages: a) constructing and positioning a platform structure, equipped before or after positioning with drilling devices and installations, b) executing drilling using these devices and installations, c) constructing and equipping, during stages a) and b), a production bridge fitted with devices and installations required for production, d) transporting the production bridge to, and positioning it on, said platform structure, and e) commencing production from deposit. The drilling bridge may remain in position on the platform structure during stages d) and e) or it may be removed to make way for the production bridge. 
     U.S. Pat. No. 4,744,697, issued to Anton Coppens, discloses a vessel that is provided for installing or removing a module on or from a support structure erected in a body of water. The vessel is able to suspend the module over the support structure by cranes enabling installation or removal of the module to be accomplished while the module is being suspended. 
     U.S. Pat. No. 5,037,241, issued to Stephen D. Vaughn et al. discloses an improved apparatus for setting a deck structure or other marine superstructure using a barge mounted cantilevered support structure. The cantilevered support structure is attached at one end of a floating vessel. The cantilevered support structure extends past the edge of the vessel and, in one embodiment, includes means for rotating parallel support members about the deck of the floating vessel permitting the cantilevered support structure to be raised and lowered while it remains substantially parallel with the top of the offshore platform enabling the superstructure to engage the top of a previously installed offshore platform in a synchronized manner. Alternatively, this superstructure may be aligned directly over the platform. A cantilevered drilling rig is then aligned over the cantilevered support structure and used to lift the deck structure or marine superstructure, permitting the vessel and cantilevered support structure to move. The drilling rig is then used to lower the marine superstructure onto the top of the previously installed offshore platform. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention provides a catamaran work barge apparatus for lifting and removing a marine platform to be salvaged or installed. The apparatus includes a pair of barges, each providing a deck area with a base that can support a large multi-ton load. 
     Each barge provides a plurality of diagonally extending lift booms. Each boom is preferably pivotally supported upon the barge that it is connected to. Each lift boom has a lower end portion that attaches to the barge on a base and an upper end portion that includes a free end with a lifting end portion. 
     Lower connection members are provided for forming attachments between the barges and the platform to be lifted and salvaged or installed. 
     A supplemental lifting frame is provided that is connectable to the package to be lifted and salvaged or installed. The supplemental lifting frame includes receptacles that receive the free end portions of the booms during a lift. 
     The supplemental lifting frame can include horizontal beams and diagonal beams associated with each boom. 
     In the preferred embodiment, there are pairs of booms that align, each of said pairs being positioned respectively on opposite of the barges. For example, in the preferred embodiment, there are four booms on each barge, producing an overall four pair of aligned booms. 
     Horizontal load spreader surfaces can be placed on the barges and spaced generally on opposite sides of the package being lifted. These load spreader surfaces or base members are at the base of each boom and pivotally support the boom, spread the load to the barge structure as required and also provide sliding or horizontal adjustment of the base of some or all booms relative to the barge upon which they are supported. 
     The supplemental lifting frame preferably comprises horizontal beams that span between booms on opposite of the barges, diagonal booms that extend from an end portion of a horizontal beam to the lower end portion of the platform and a connection that joins the horizontal beams and diagonal beams with a pinned arrangement that disallows substantial bending moment in the horizontal beam and in the platform leg. 
     Each boom can be provided with a winch with a cable wound thereupon. The lower connections can include cables such as winch cables that span between the barges and the platform. 
     The present invention provides a method for the offshore salvage or installation of a fixed offshore platform. The method includes transporting a catamaran work platform to a desired site of the fixed offshore structure. The catamaran work platform including a pair of barge supported decks that are positioned at spaced apart and generally parallel positions relative to one another. 
     A lifting assembly is attached to the platform at multiple positions, including positions that are at least on generally opposite sides of the platform, and at upper and lower positions on the platform. The lifting assembly includes two opposed lifting booms, each connected by at least one lifting end portion to a frame that is attachable to the platform. The method further comprises pulling the two barge decks together. 
     In the method, the frame includes a horizontal beam that spans between the upper end portion of two aligned booms. 
     The method further comprises the step of subjecting the horizontal beams of the frame to compression only and little or no bending moment during the lift. 
     There are preferably two opposed lift barges as part of the method, each being a separate floating barge. However, a one piece barge construction could be provided that has separate spaced apart decks that carry the respective sets of lifting booms. 
     The lifting assembly can include a plurality of non-extensible diagonally extending lift booms, each removably connected at its ends to an end cap. dr 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein: 
     FIG. 1 is a perspective view of the preferred embodiment of the apparatus of the present invention; 
     FIG. 2 is a partial perspective view of the preferred embodiment of the apparatus of the present invention showing the connection made between the lower end portion of the leg of a platform to be removed or installed and the apparatus of the present invention; 
     FIG. 3 is a fragmentary, exploded, perspective view of the preferred embodiment of the apparatus of the present invention; 
     FIG. 4 is a fragmentary, sectional view of the preferred embodiment of the apparatus of the present invention illustrating the connection between horizontal and diagonal beam members; 
     FIG. 5 is a fragmentary frontal view of the preferred embodiment of the apparatus of the present invention showing the pin portion thereof; 
     FIG. 6 is another view of the pin portion of the preferred embodiment of the apparatus of the present invention; 
     FIG. 7 is an end view of the pin portion of the preferred embodiment of the apparatus of the present invention; 
     FIG. 8 is an end view of the retainer ring portion of the preferred embodiment of the apparatus of the present invention; 
     FIG. 9 is a fragmentary, perspective view of the preferred embodiment of the apparatus of the present invention illustrating the pin and retainer ring portions thereof; 
     FIG. 10 is a fragmentary, perspective view of the preferred embodiment of the apparatus of the present invention showing an end of one of the lifting booms; 
     FIG. 11 is a sectional view taken along lines  11 — 11  of FIG. 10; and 
     FIG. 12 is a partial, elevational view of the apparatus of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows the preferred embodiment of the apparatus of the present invention designated generally by the numeral  10 . Marine platform lifting apparatus  10  includes spaced apart barges  11 ,  12  that can provide deck surfaces for supporting a plurality of booms and winches. In FIG. 1, the barge  11  provides a deck surface  11 A having a plurality of booms  13 ,  14 ,  15 ,  16 , each pivotally mounted thereon. Barge  12  provides a deck surface  12 A with a corresponding plurality of booms  17 ,  18 ,  19 ,  20 . 
     The booms  13 - 20  are paired, with opposing booms being aligned along a plane of rotation with each other. Booms  13  and  17  are aligned and form a plane with their pivotal or rotational arcs. Likewise, pairs of aligned booms include  14  and  18 ,  15  and  19 , and  16  and  20 . Each of the booms  13 - 20  is supported upon a base  21  that can be comprised of a frame, pad eyes, and pinned connections, so that each boom  13 - 20  is pivotally movable at the barge  11  or  12  and with respect to the barge  11  or  12 . Each base  21  is a load transfer interface between a boom and its barge. 
     A winch (e.g. hydraulic) 22  is also provided with each boom  13 - 20 . In FIG. 12, a single winch  22  is shown for purposes of clarification. Winch cable  23  is wound upon winch  22 . Winches  22  can be large, commercially available winches that are driven with diesel engines. Winch cable  23  is preferably a steel cable having a high tensile strength. 
     Sheave blocks are used to interface winch line  23  with the barges  11 ,  12  and the platform  30  to be salvaged or installed, as shown in FIGS. 1,  2  and  12 . Sheave blocks  24  are pinned to base  21  at the lower end of each boom, In FIG. 12, boom  16  shows block  24  pivotally connected to base  21  at a pinned connection  81 . Pinned connection  81  can be a common pinned connection that joins each boom to its base (e.g. boom  16  to base  21  in FIG. 12) and also connecting sheave block  24  to base  21 . As shown in FIG. 1, each boom  13 - 20  can be comprised of a pair of longitudinally extended boom members  25 ,  26 . Each boom member  25 ,  26  pivotally mounts to a base  21  as shown in FIG.  1 . Some or all of the bases  21  can be slidably or adjustably mounted to barge  11  or  12 , enabling adjustment when booms  13 - 20  are positioned to lift platform  30  to be salvaged or installed. A load spreader  27  is part of the tension connection that extends between the base  21  of each boom  13 - 20  and platform  30  to be salvaged or installed at vertical leg  31 . In FIG. 2, the load spreader  27  provides a pair of blocks  28 ,  29  connected thereto using links  32 . Load spreader  27  has a pad eye  33  that attaches to block  34  with pinned connection  35 . Leg  31  of platform  30  is provided with pad eyes  36 ,  41 . Pad eye  36  forms a connection at pinned connection  37  to pad eye  34  as shown in FIG.  2 . Similarly, a connection is formed between leg  31  at its pad eyes  36  with diagonal beams  40 . A load spreader  38  forms an interface between the two diagonal beams  40  shown in FIG.  2  and leg pad eyes  36 . A pinned connection  39  connects load spreader  38  to leg pad eye  36  as shown in FIG.  2 . 
     Leg pad eyes  41  can be provided at about 180 degrees opposite to leg pad eyes  36 . This enables a tensile connection to be perfected between barges  11  and  12  at each lifting boom  13 - 20 . Horizontal beam  42  is connected to leg pad eye  41  at pinned connection  43 . A tensile connection is formed between the winches  22  of barge  11  and the winches  22  of barge  12  at each aligned pair of booms such as boom  16  and boom  20 . Each barge  11 ,  12  provides the connection shown in FIGS. 1 and 2 between an opposing pair of aligned booms ( 13  and  17 ,  14  and  18 ,  15  and  19 ,  16  and  20 ) and their base supports  21 . For example, in FIG. 1, the boom  13  of barge  11  aligns with the boom  17  of barge  12 . Likewise, the boom  16  of barge  11  aligns with the boom  20  of barge  12 . The tensile connection shown in FIGS. 2 and 12 is representative of the connection made between each barge  11  and the vertical leg  31  of platform  30 . The arrangement of boom  20  on barge  12  is thus a mirror image of FIG.  2 . If the platform  30  does not have a horizontal beam spanning between two legs  31  at plates  41 , and along a line that connects the bases  21  of an aligned pair of booms such as  16  and  20 , horizontal beam  42  can be added using pinned connections  43  as shown in FIGS. 1,  2  and  12 . 
     Horizontal beams  44 ,  45  each extend between the upper end of each boom (such as boom  16 ) and the associated, aligned boom such as boom  20  in FIG.  1 . Preferably a pair of horizontal beams  44 ,  45  extend between the upper end portion of boom  16  and the upper end portion of boom  20 . The connection between the aligned booms  16  and  20  with diagonal beams  40  and horizontal beams  44 ,  45  is best seen in FIGS. 1,  3 ,  4  and  12 . 
     Each of the booms  13 - 20  can include removable end caps that are at end portions of the boom members  25 ,  26 . As shown in FIG. 10, the upper end portion of each of the boom members  25 ,  26  can be provided with an end cap  46 ,  47 , respectively. At the lower end of each boom member  25 ,  26 , there can also be provided end caps  75 . The end caps  75  at the lower end of the boom members  25 ,  26  can attach (e.g. pinned) to a pad eye block  77 . A pinned connection  76  can be used to join the pad eye block  77  to base  21  of each boom  13 - 20 . This construction that includes boom members  25 ,  26  and its removable end caps  46 ,  47 ,  77  enables the length of the booms  13 - 20  to be varied from one job to the next as the end caps  46 ,  47 ,  77  are reusable. By using different length boom members  25 ,  26 , taller or shorter platforms  30  can be salvaged or installed. 
     In FIG. 10, boom end  48  is attached to end caps  46 ,  47  using pinned connections  51 ,  52 . Boom end  49  is comprised of a pair of plates  48 ,  50  that are welded to a second pair of plates  53 ,  54  as shown in FIG.  10 . The plates  53 ,  54  each have a recess that fits a pin  60 . The pin  60  connects diagonal beams  40  to horizontal beams  44 ,  50  as shown in FIGS. 2,  3  and  4 . Plate  53  has recess  55 . Plate  54  has recess  56 . Each of the recesses  55 ,  56  provides a convex surface  57 ,  58  as shown in FIG.  11 . 
     In FIG. 3, arrows  59  illustrate the assembly of plates  53 ,  54  that are part of boom end  48  to pins  60  that are connected to beams  40 ,  44  and  45 . The ends of diagonal beams  40  align with the ends of the beams  44 ,  45  with pins  60  being placed through openings  71  of beams  44 ,  45  and  74  of beams  40 . 
     The construction of pin  60  is shown more particularly in FIGS. 5-7 and  9 . Also shown in FIGS. 8 and 9 is retainer  61  that holds each pin  60  in operating position. Pins  60  include spaced apart larger diameter sections  65 ,  66 , each having external threads  67  at the extreme end  68  of pin  60 . Ends  68  of pin  60  are generally flat. Retainers  61  have openings  69  with internal threads  70  that engage the external threads  67  of pin  60  upon assembly. Most of larger diameter sections  24 ,  25  are cylindrical in shape. However, pin  60  has a flat surface  62  (see FIG. 6) A center section  64  of pin  60  carries concave surface  63 . During use, center section  64  of pin  60  is exposed so that it can be engaged by the convex surfaces  57 ,  58  of plates  53 ,  54  of boom end  48  at plates  53 ,  54  and recesses  55 ,  56 . 
     It should be understood that the opening  71  at the end of each beam  45  is an enlarged or over sized opening defined by flat surface  72  and curved surface  73 . In FIG. 4, pin  60  is shown having a maximum diameter that is smaller than the maximum height of opening  71 , providing gaps at  78  and  79 . This enables the pin  60  to travel up and down with respect to oversized opening  71  so that no substantial bending moment is created in beams  44 ,  45 . 
     Conversely, diagonal beams  40  have pin openings  74  that are slightly larger than but substantially equal to the maximum diameter of large ends  65 ,  66  of pin  60 . 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 PARTS LIST 
               
             
          
           
               
                 Part Number 
                 Description 
               
               
                   
               
               
                 10 
                 marine platform lifting apparatus 
               
               
                 11 
                 barge 
               
               
                     11A 
                 deck surface 
               
               
                 12 
                 barge 
               
               
                     12A 
                 deck surface 
               
               
                 13 
                 boom 
               
               
                 14 
                 boom 
               
               
                 15 
                 boom 
               
               
                 16 
                 boom 
               
               
                 17 
                 boom 
               
               
                 18 
                 boom 
               
               
                 19 
                 boom 
               
               
                 20 
                 boom 
               
               
                 21 
                 base 
               
               
                 22 
                 winch 
               
               
                 23 
                 winch cable 
               
               
                 24 
                 sheave block 
               
               
                 25 
                 boom member 
               
               
                 26 
                 boom member 
               
               
                 27 
                 load spreader 
               
               
                 28 
                 block 
               
               
                 29 
                 block 
               
               
                 30 
                 platform 
               
               
                 31 
                 vertical leg 
               
               
                 32 
                 link 
               
               
                 33 
                 pad eye 
               
               
                 34 
                 block 
               
               
                 35 
                 pinned connection 
               
               
                 36 
                 leg pad eye 
               
               
                 37 
                 pinned connection 
               
               
                 38 
                 load spreader 
               
               
                 39 
                 pinned connection 
               
               
                 40 
                 diagonal beams 
               
               
                 41 
                 leg pad eye 
               
               
                 42 
                 horizontal beam 
               
               
                 43 
                 pinned connection 
               
               
                 44 
                 horizontal beam 
               
               
                 45 
                 horizontal beam 
               
               
                 46 
                 end cap 
               
               
                 47 
                 end cap 
               
               
                 48 
                 boom end 
               
               
                 49 
                 plate 
               
               
                 50 
                 plate 
               
               
                 51 
                 pinned connection 
               
               
                 52 
                 pinned connection 
               
               
                 53 
                 plate 
               
               
                 54 
                 plate 
               
               
                 55 
                 recess 
               
               
                 56 
                 recess 
               
               
                 57 
                 convex surface 
               
               
                 58 
                 convex surface 
               
               
                 59 
                 arrow 
               
               
                 60 
                 pin 
               
               
                 61 
                 retainer 
               
               
                 62 
                 flat surface 
               
               
                 63 
                 concave surface 
               
               
                 64 
                 center section 
               
               
                 65 
                 larger diameter section 
               
               
                 66 
                 larger diameter 
               
               
                 67 
                 external thread 
               
               
                 68 
                 flat end 
               
               
                 69 
                 opening 
               
               
                 70 
                 internal thread 
               
               
                 71 
                 oversized  pin opening 
               
               
                 72 
                 flat surface 
               
               
                 73 
                 curved surface 
               
               
                 74 
                 pin opening 
               
               
                 75 
                 end cap 
               
               
                 76 
                 pinned connection 
               
               
                 77 
                 pad eye block 
               
               
                 78 
                 gap 
               
               
                 79 
                 gap 
               
               
                 80 
                 gap 
               
               
                 81 
                 pinned connection 
               
               
                   
               
             
          
         
       
     
     Because many varying and different embodiments may be made within the scope of the inventive concept herein taught, and because many modifications may be made in the embodiments herein detailed in accordance with the descriptive requirement of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense.