Abstract:
A method of elevating the deck area of a marine platform (e.g. oil and gas well drilling or production platform) utilizes a specially configured sleeve support to support the platform legs so that they can be cut. Once cut, jacks elevate the platform above the cuts. The sleeve support is then connected (e.g. welded) to the platform leg and becomes part of the structural support for the platform.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Priority of U.S. Provisional Patent Application Ser. No. 60/824,005, filed Aug. 30, 2006, incorporated herein by reference, is hereby claimed. 
    
    
     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 marine platforms such as oil and gas well drilling platforms. More particularly, the present invention relates to an improved method and apparatus for elevating the deck area of a fixed marine platform to better protect equipment that is located on the deck area from storms (e.g. hurricanes) that generate heightened wave action. 
     2. General Background of the Invention 
     There are many fixed platforms located in the oil and gas well drilling areas off the United States coast such as in the Gulf of Mexico. Such marine platforms typically employ an undersea support structure that is commonly referred to as a jacket. These jackets can be many hundreds of feet tall, being sized to extend between the seabed and the water surface area. Jackets are typically constructed of a truss like network of typically cylindrically shaped pipe, conduit or tubing that is welded together. The jackets can be secured to the seabed using pilings that are driven into the seabed. The jacket is then secured to the piling. The part of the offshore marine platform that extends above the jacket and above the water surface is typically manufactured on shore and placed upon the jacket using known lifting equipment such as a derrick barge. This upper portion is the working part of the platform that is inhabited by workers. 
     Marine platforms can be used to perform any number of functions that are associated typically with the oil and gas well drilling and production industry. Such platforms can be used to drill for oil and gas. Such platforms can also be used to produce wells that have been drilled. These fixed platforms typically provide a deck area that can be crowded with extensive equipment that is used for the drilling and/or production of oil and gas. 
     When storms strike the Gulf of Mexico and other areas, offshore marine platforms are put at risk. While the jacket and platform are typically designed to resist hurricane force wind and wave action, equipment located on the deck of the marine platform can easily be damaged if hurricane generated wave action reaches the deck area. 
     An additional consequence of wave action reaching the platform deck is catastrophic platform collapse, which happened in several instances during recent storms in the United States Gulf of Mexico. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention solves these prior art problems and shortcomings by providing a method and apparatus for elevating the deck area of an existing marine platform so that equipment that occupies the deck can be further distanced from the water surface. The method of the present invention this provides more clearance, more freeboard and more protection to deck area equipment during severe storms such as hurricanes. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS 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 schematic, elevation view of a fixed marine platform; 
         FIG. 2  is a perspective view illustrating a method step of the present invention; 
         FIG. 3  is a perspective view illustrating a method step of the present invention; 
         FIG. 4  is a perspective view illustrating a method step of the present invention, placement of the upper and lower bushing sleeves; 
         FIG. 5  is a partial perspective view of the preferred embodiment of the apparatus of the present invention illustrating placement of the upper and lower bushing sleeves; 
         FIG. 6  is a partial perspective view of the preferred embodiment of the apparatus of the present invention illustrating a method step of the present invention; 
         FIG. 7  is a partial perspective view of the preferred embodiment of the apparatus of the present invention illustrating one of the extension sleeve guides; 
         FIG. 8  is a sectional view taken along lines  8 - 8  of  FIG. 7 ; 
         FIG. 9  is a partial elevation view of the preferred embodiment of the apparatus of the present invention illustrating placement of the extension sleeve guides; 
         FIG. 10  is a partial elevation view of the preferred embodiment of the apparatus of the present invention showing positions of the leg cuts; 
         FIG. 11  is a partial perspective exploded view of the preferred embodiment of the apparatus of the present invention; 
         FIG. 12  is a partial perspective view of the preferred embodiment of the apparatus of the present invention illustrating the method of the present invention, placement of the upper ring; 
         FIG. 13  is a partial elevation view of the preferred embodiment of the apparatus of the present invention illustrating placement of the upper ring; 
         FIG. 14  is a partial perspective exploded view of the preferred embodiment of the apparatus of the present invention illustrating placement of the hydraulic pistons; 
         FIG. 15  is a partial perspective view of the preferred embodiment of the apparatus of the present invention illustrating placement of the hydraulic pistons; 
         FIG. 16  is a fragmentary elevation view illustrating the method of the present invention, namely the step of completing the leg cuts; 
         FIG. 17  is a fragmentary perspective of the preferred embodiment of the apparatus of the present invention illustrating extension of the leg with the hydraulics pistons; 
         FIG. 18  is a partial perspective view of the method and apparatus of the present invention, showing the method step of closing the sleeve openings; and 
         FIG. 19  is an elevation view of the preferred embodiment of the apparatus of the present invention illustrating the marine platform after its deck area has been elevated using the method and apparatus of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention provides a marine platform deck elevating system  10  that is shown generally in  FIGS. 14-15  and  17  and in method steps that are illustrated in  FIGS. 2-18 . 
     In  FIG. 1 , a fixed marine platform  11  is shown having a deck  16  that is positioned at an elevation  18  that is elevated above the water surface  12  a distance H 1  that is indicated by the numeral  19  in  FIG. 1 . The numeral  19  and the dimension line H 1  represent the existing clearance above water. It is necessary to protect equipment that is contained on the deck  16  from storm generated wave action. In the Gulf of Mexico, hurricanes can generate a storm surge and wave action that puts equipment and/or personnel located on deck  16  at peril. If a deck is not located at a safe elevation, it must be elevated.  FIG. 1  illustrates a typical fixed platform  11  having a plurality of legs  14  that support the deck  16 . Diagonal braces  17  can extend between legs  14  and deck  16  as shown in  FIG. 1 . The platform  11  can include other structure such as for example horizontal beams or members and/or additional vertical or diagonal members. 
     Legs  14  can be of a constant diameter or can include tapered sections  13 , wherein the diameter of the upper leg section  15 A is less than the diameter of the lower leg section  15 B. Leg  14  can thus include a number of different leg sections such as a lower, larger diameter leg section  15 B, a tapered leg section  13 , and an upper, smaller diameter leg section  15 A that is positioned above the tapered section  13 . The method and apparatus of the present invention can be used to elevate the deck  16  to a new elevation  20  (see  FIG. 19 ) that is higher than the previous, existing deck elevation  18  of  FIG. 1 . The method and apparatus of the present invention thus provides a new clearance  21  above water surface  12  (also shown by the arrow H 2  in  FIG. 19 ). 
       FIGS. 2 and 3  illustrate an initial method step of the present invention, namely the placement of lower bushing sleeve  24 . The lower bushing sleeve  24  can be comprised of a pair of half sleeve sections  22 ,  23  as shown in  FIGS. 2-3 . The sections  22 ,  23  can be joined with welds  26  as shown in  FIGS. 3-4 . Arrows  25  in  FIG. 2  schematically illustrate the placement of sleeve sections  22 ,  23  upon leg  14  at a position below tapered section  13  as shown. 
     In  FIGS. 4-6 , upper bushing sleeve  29  can also be comprised of a pair of sleeve half sections. The sleeve sections  27 ,  28  each provide an opening  35  or  36  that is receptive of a pin  50  as will be explained more fully hereinafter. Weld ring sections  30 ,  31  can be used to attach the sleeve sections  27 ,  28  to tapered section  13 . As with the lower bushing sleeve  24 , one or more welds  37  can be used to join the sleeve sections  27 ,  28  to each other. Arrows  33  in  FIG. 4  illustrate the placement of sleeve sections  27 ,  28  upon tapered section  13 . Arrows  34  in  FIG. 4  illustrate the attachment of weld ring  32  to the assembly of sleeve sections  27 ,  28  and to tapered section  13 . 
     In  FIGS. 6-9  and  11 , a plurality of extension sleeve guides  38  are shown. These extension sleeve guides  38  are attached to the platform  11  leg  14  at a position that is above upper bushing sleeve  29 . The extension sleeve guides  38  can extend from tapered section  13  to smaller diameter leg section  15 A as shown in  FIGS. 6 and 9 . Arrows  39  illustrate placement of extension sleeve guides  38  to leg  14 . Each extension sleeve  38  can be comprised of flanges  40  and webs  41 . The web  41  actually contacts the leg  14  and can be shaped to conform to the shapes of tapered section  13  and smaller diameter leg section  15 A as shown in  FIGS. 7 and 9  (see DIM “A”,  FIG. 7 ). 
     In  FIGS. 10-15 , an extension sleeve  44  can be comprised of a pair of extension sleeve sections  45 ,  46 . Each extension sleeve section  45 ,  46  has slots  47 ,  48  that can be used to complete a cut through the leg  14  after the sleeve sections  45 ,  46  have been attached to leg  14  and guides  38 . 
     Before attachment of the sleeve sections  45 ,  46  four cuts are made through leg  14  as shown in  FIG. 10 . The cuts  42 ,  43  do not extend 360 degrees around the leg  14 , but rather extend only a partial distance as shown in  FIG. 10 . Though partial cuts  42 ,  43  are made, enough of the leg  14  remains to structurally support the platform  11  and its deck  16  considering the use of sleeve  44  and the method of the present invention disclosed herein. 
     After the sleeve sections  45 ,  46  have been installed, a cut can be made to encircle the leg  14  thus severing it in two parts. In order to complete the cut, slots are provided in the sleeve sections  45 ,  46 . In  FIG. 11 , the sleeve section  45  has slot  47 . In  FIG. 11 , the sleeve section  46  has slot  48 . 
     After installing the upper bushing sleeve  29 , circular cut openings  49  are made through the leg  14  at the openings  35 ,  36  in the sleeve sections  27 ,  28 . These cut openings  49  enable pin  50  to be placed through the openings  67 ,  68  in sleeve sections  45 ,  46  respectively as well as through the openings  49  in upper bushing sleeve  29 . Pin  50  prevents uplift from damaging the platform  11  should a storm produce excess wave action before the method of the present invention can be completed. 
     Each of the sleeve sections  45 ,  46  provides lugs to which hydraulic pistons can be attached. Sleeve section  45  provides a plurality of lugs  51 . Sleeve section  46  provides a plurality of lugs  52 . Each of the lugs provides an opening for enabling a pinned connection to be made between the lugs  51 ,  52  and the hydraulic pistons  64 . Lugs  51  provide openings  53 . Lugs  52  provide openings  54 . In the preferred method and apparatus, four pairs of lugs  51 ,  52  are thus provided to the extension sleeve  44 . Each pair of lugs  51 ,  52  can be spaced circumferentially about sleeve  44 , about 90 degrees apart. 
     A ring  55  is positioned above extension sleeve  44  as shown in  FIGS. 12-15  and  17 - 19 . Ring  55  is used to form a connection between the leg  14  and the hydraulic piston  64 . Ring  55  can be formed of a pair of ring sections  56 ,  57  that are attached to the smaller diameter leg section  15 A as shown in  FIGS. 12 and 13 . Each of the ring sections  56 ,  57  provides a plurality of lugs  58 ,  59 . The ring section  56  has lugs  58 . The ring section  57  has lugs  59 . Each lug  58 ,  59  has a lug opening  60  that enables a pinned connection to be made between a lug  58  or  59  and a piston  64 . Each ring section  56 ,  57  can be formed of arcuate generally horizontal plate sections and vertical plate sections. Each of the ring sections  56 ,  57  thus provide an upper arcuate plate section  61  and a lower arcuate plate section  62 . Vertical plate sections  63  span between the upper and lower arcuate plate sections  61 ,  62 . 
     Hydraulic pistons  64  are provided for elevating that portion of the leg  14  that is above the cuts that are made through the leg  14  (see  FIGS. 10 and 16 ). Preferably three (3) or four (4) pistons can be used, but as few as two (2) rams can be used or more, such as many as eight (8) could be used for example. 
     Each hydraulic piston  64  can be comprised of a cylinder  65  and an extensible push rod  66 . Each end portion of hydraulic piston  64  provides an opening  69  on cylinder  65  that enables a pinned connection to be formed between each end of hydraulic piston  64  and lugs  51 ,  52  or  58 ,  59 . The upper end portion of each hydraulic piston  64  attaches with a pinned connection to a lug  58  or  59  that is a part of ring  55 . The lower end portion of each hydraulic piston  64  forms a pinned connection with the lugs  51 ,  52  of extension sleeve  44  as shown in  FIGS. 14-15 . Arrows  74  in  FIG. 14  illustrate assembly of pistons  64  to lugs  51 ,  52 ,  58 ,  59 . 
     Once the hydraulic pistons  64  have been installed to the position shown in  FIG. 15 , a cut can be completed for severing leg  14 . This can be seen in more detail in  FIGS. 10 ,  15 - 16  wherein the previously formed cuts  42 ,  43  are shown. Notice that uncut portions  70  (DIM “B”,  FIG. 16 ) of leg  14  align with the slots  47  or  48  of sleeve sections  45 ,  46 . The leg  14  can thus be cut 360 degrees by cutting the previously uncut section  70  at slot  47  or  48 , indicated by phantom lines as cut  73  in  FIG. 16 . The three hundred sixty degree cut ( 42 ,  43 ,  73 ) is made after the extension sleeve  14 , hydraulic pistons  64  and ring  55  form a structural support of the leg  14  above and below the cuts  42 ,  43 . In order to then elevate the smaller diameter leg section  15 A relative to the larger diameter leg section  15 B below tapered section  13 , each hydraulic piston  64  can be activated as illustrated by arrows  72  in  FIG. 17 . 
     Once elevated, the various openings and slots in sleeve  44  can be covered for corrosion protection using a plurality of curved cover plate sections  71 . To complete the repair, the sleeves  44  can be welded to the leg  14  and using shims as necessary between sleeve  44  and leg  14 , tapered section  13  or sections  15 A,  15 B. While the method disclosed herein contemplates that the elevation process would preferably take place as one jacking operation. The invention should not be so restricted. The method of the present invention contemplates a method wherein the jacking process could be subdivided into several smaller (or shorter) jacking elevations. The legs  14  would be pinned off at an intermediate point and the jacks moved to a second set of lugs. Arrow  75  in  FIG. 17  shows the distance that the upper leg section  15 A is elevated. 
     The following is a list of parts and materials suitable for use in the present invention. 
     PARTS LIST 
     
       
         
               
               
             
           
               
                   
               
               
                 Part Number 
                 Description 
               
               
                   
               
             
             
               
                 10 
                 marine platform deck elevating 
               
               
                   
                 system 
               
               
                 11 
                 platform 
               
               
                 12 
                 water surface 
               
               
                 13 
                 tapered section 
               
               
                 14 
                 leg 
               
               
                   15A 
                 smaller diameter leg section 
               
               
                   15B 
                 larger diameter leg section 
               
               
                 16 
                 deck 
               
               
                 17 
                 diagonal brace 
               
               
                 18 
                 existing deck elevation 
               
               
                 19 
                 existing clearance above water 
               
               
                 20 
                 new deck elevation 
               
               
                 21 
                 new clearance above water 
               
               
                 22 
                 sleeve section 
               
               
                 23 
                 sleeve section 
               
               
                 24 
                 lower bushing sleeve 
               
               
                 25 
                 arrow 
               
               
                 26 
                 weld 
               
               
                 27 
                 sleeve section 
               
               
                 28 
                 sleeve section 
               
               
                 29 
                 upper bushing sleeve 
               
               
                 30 
                 weld ring section 
               
               
                 31 
                 weld ring section 
               
               
                 32 
                 weld ring 
               
               
                 33 
                 arrow 
               
               
                 34 
                 arrow 
               
               
                 35 
                 opening 
               
               
                 36 
                 opening 
               
               
                 37 
                 weld 
               
               
                 38 
                 extension sleeve guide 
               
               
                 39 
                 arrow 
               
               
                 40 
                 flange 
               
               
                 41 
                 web 
               
               
                 42 
                 cut 
               
               
                 43 
                 cut 
               
               
                 44 
                 extension sleeve 
               
               
                 45 
                 extension sleeve section 
               
               
                 46 
                 extension sleeve section 
               
               
                 47 
                 slot 
               
               
                 48 
                 slot 
               
               
                 49 
                 drilled opening 
               
               
                 50 
                 support pin 
               
               
                 51 
                 lug 
               
               
                 52 
                 lug 
               
               
                 53 
                 opening 
               
               
                 54 
                 opening 
               
               
                 55 
                 ring 
               
               
                 56 
                 ring section 
               
               
                 57 
                 ring section 
               
               
                 58 
                 lug 
               
               
                 59 
                 lug 
               
               
                 60 
                 lug opening 
               
               
                 61 
                 upper arcuate plate section 
               
               
                 62 
                 lower arcuate plate section 
               
               
                 63 
                 vertical plate section 
               
               
                 64 
                 hydraulic piston 
               
               
                 65 
                 cylinder 
               
               
                 66 
                 pushrod 
               
               
                 67 
                 opening 
               
               
                 68 
                 opening 
               
               
                 69 
                 opening 
               
               
                 70 
                 uncut portion 
               
               
                 71 
                 cover plate 
               
               
                 72 
                 arrows 
               
               
                 73 
                 cut 
               
               
                 74 
                 arrow 
               
               
                 75 
                 arrow 
               
               
                   
               
             
          
         
       
     
     All measurements disclosed herein are at standard temperature and pressure, at sea level on Earth, unless indicated otherwise. All materials used or intended to be used in a human being are biocompatible, unless indicated otherwise. 
     The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims.