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US20120114421A1 - Semi-submersible floating structure - Google Patents

Semi-submersible floating structure Download PDF

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Publication number
US20120114421A1
US20120114421A1 US13/383,438 US201013383438A US2012114421A1 US 20120114421 A1 US20120114421 A1 US 20120114421A1 US 201013383438 A US201013383438 A US 201013383438A US 2012114421 A1 US2012114421 A1 US 2012114421A1
Authority
US
United States
Prior art keywords
columns
column
buoyant
deck
heave
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US13/383,438
Other languages
English (en)
Inventor
Arno Laurentius Michael Van Den Haak
Yile Li
You Sun Li
Stergios Liapis
Joao Paulo Juliao Matsuura
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shell USA Inc
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US13/383,438 priority Critical patent/US20120114421A1/en
Assigned to SHELL OIL COMPANY reassignment SHELL OIL COMPANY ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: VAN DEN HAAK, ARNO LAURENTIUS MICHAEL, LI, YILE, LI, YOU SUN, LIAPIS, STERGIOS, MATSUURA, JOAO PAULO JULIAO
Publication of US20120114421A1 publication Critical patent/US20120114421A1/en
Abandoned legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B35/00—Vessels or similar floating structures specially adapted for specific purposes and not otherwise provided for
    • B63B35/44—Floating buildings, stores, drilling platforms, or workshops, e.g. carrying water-oil separating devices
    • B63B35/4413—Floating drilling platforms, e.g. carrying water-oil separating devices
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B1/00—Hydrodynamic or hydrostatic features of hulls or of hydrofoils
    • B63B1/02—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving lift mainly from water displacement
    • B63B1/10—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving lift mainly from water displacement with multiple hulls
    • B63B1/107—Semi-submersibles; Small waterline area multiple hull vessels and the like, e.g. SWATH
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B1/00—Hydrodynamic or hydrostatic features of hulls or of hydrofoils
    • B63B1/02—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving lift mainly from water displacement
    • B63B1/10—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving lift mainly from water displacement with multiple hulls
    • B63B1/12—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving lift mainly from water displacement with multiple hulls the hulls being interconnected rigidly
    • B63B2001/128—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving lift mainly from water displacement with multiple hulls the hulls being interconnected rigidly comprising underwater connectors between the hulls
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B35/00—Vessels or similar floating structures specially adapted for specific purposes and not otherwise provided for
    • B63B35/44—Floating buildings, stores, drilling platforms, or workshops, e.g. carrying water-oil separating devices
    • B63B2035/448—Floating hydrocarbon production vessels, e.g. Floating Production Storage and Offloading vessels [FPSO]
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B39/00—Equipment to decrease pitch, roll, or like unwanted vessel movements; Apparatus for indicating vessel attitude
    • B63B39/06—Equipment to decrease pitch, roll, or like unwanted vessel movements; Apparatus for indicating vessel attitude to decrease vessel movements by using foils acting on ambient water
    • B63B2039/067—Equipment to decrease pitch, roll, or like unwanted vessel movements; Apparatus for indicating vessel attitude to decrease vessel movements by using foils acting on ambient water effecting motion dampening by means of fixed or movable resistance bodies, e.g. by bilge keels

Definitions

  • Embodiments disclosed herein generally relate to floating structures used in an offshore environment.
  • Top tensioned risers with dry trees located on the surface structure allow direct vertical access to subsea wells.
  • Spar type structures have sufficiently low motions so that they can be used with top tensioned risers and dry trees. Spars have the disadvantage that they have to be towed into location horizontally, then upended in place, and the decks lifted onto the spar structure.
  • Semisubmersibles generally have too much motion to be used with top tensioned risers and dry trees, so they are traditionally used with steel catenary risers that tie back to subsea wet trees. Semisubmersibles have the advantage over spars that their decks can be installed on shore, and then the structure with decks can be towed into location.
  • U.S. Pat. No. 3,397,545 discloses a movable marine structure including buoyant columns having damping plates and fins.
  • U.S. Pat. No. 3,397,545 is herein incorporated by reference in its entirety.
  • U.S. Pat. No. 5,558,467 discloses a deep water offshore apparatus for use in oil drilling and production in which an upper buoyant hull of prismatic shape is provided with a passage longitudinally extending through the hull in which risers run down to the sea floor, the bottom of the hull being located at a selected depth dependent upon the wind, wave, and current environment at the well site, which significantly reduces the wave forces acting on the bottom of the hull, a frame structure connected to the hull bottom and extending downwardly and comprising a plurality of vertically arranged bays defined by vertically spaced horizontal water entrapment plates and providing open windows around the periphery of the frame structure, the windows providing transparency to ocean currents and to wave motion in a horizontal direction to reduce drag, the vertical space between the plates corresponding to the width of the bay window, the frame structure being below significant wave action whereby wave action thereat does not contribute to heave motion of the apparatus but inhibits heave motion, the frame structure serving to modify the natural period and stability of the apparatus to
  • U.S. Pat. No. 5,558,467 is herein incorporated by reference in its entirety.
  • U.S. Pat. No. 7,086,809 discloses an apparatus for use in offshore oil or gas production in which a plurality of vertical stabilizing columns are supported on a submerged horizontal water entrapment plate is provided to support minimum offshore oil and gas production facilities above a subsea wellhead, or subsea processing facilities, or a submarine pipeline, and whose main function is to provide power or chemicals or to perform other operations such as compression, injection, or separation of water, oil and gas.
  • the apparatus is maintained in the desired location by a plurality of mooring lines anchored to the sea-bed.
  • U.S. Pat. No. 7,281,881 discloses an apparatus for use in offshore oil or gas production in which a plurality of vertical stabilizing columns are supported on a submerged horizontal water entrapment plate to support minimum offshore oil and gas production facilities above a subsea wellhead, or subsea processing facilities, or a submarine pipeline, and whose main function is to provide power or chemicals or to perform other operations such as compression, injection, or separation of water, oil and gas.
  • the apparatus is maintained in the desired location by a plurality of mooring lines anchored to the sea-bed.
  • U.S. Pat. No. 7,191,836 discloses compliant variable tension risers to connect deep-water subsea wellheads to a single floating platform.
  • the variable tension risers allow several subsea well-heads, in water depths from 4,000 to 10,000 feet, at lateral offsets from one-tenth to one-half of the depth, to tie back to a single floating dry tree semi-submersible platform. Also disclosed are methods to counter buoyancy and install variable tension risers using a weighted chain ballast line.
  • U.S. Pat. No. 7,191,836 is herein incorporated by reference in its entirety.
  • Results show that by keeping the displaced volume of the hull constant the relative areas of the column and pontoon can be varied to affect the magnitude of the hydrodynamic forces on the columns and pontoon and thus the shape of the heave RAO.
  • the “Hydrodynamics of Dry Tree Semisubmersibles” paper is herein incorporated by reference in its entirety.
  • offshore structures to accommodate a number of riser configurations; a lower cost offshore structure; a direct vertical access offshore structure; an offshore structure that allows for quayside topsides installation; an offshore structure with reduced heave; an offshore structure connected to one or more top tensioned risers; an offshore structure from which to do drilling operations; a semisubmersible offshore structure with reduced motions; and/or a semisubmersible offshore structure with drilling operations.
  • One aspect of the invention provides a floating system comprising a plurality of buoyant columns, a top portion of the columns extending above a water surface, and a bottom portion of the columns submerged in a body of water; a deck connected to the top portion of the columns; at least one pontoon connected to the bottom portion of at least two of the columns; a plurality of heave plates, each heave plate connected to the bottom portion of at least one of the columns; and a conduit connected to the deck and extending to a bottom of the body of water.
  • FIG. 1A shows an offshore floating structure in accordance with embodiments disclosed herein.
  • FIG. 1B shows a cross-sectional view of the offshore floating structure of FIG. 1A .
  • FIG. 1C shows a close-up view of a portion of FIG. 1B .
  • FIG. 2 shows an offshore floating structure in accordance with embodiments disclosed herein.
  • FIG. 3 shows an offshore floating structure in accordance with embodiments disclosed herein.
  • FIG. 4 a shows an offshore floating structure in accordance with embodiments disclosed herein.
  • FIG. 4 b shows an offshore floating structure in accordance with embodiments disclosed herein.
  • FIGS. 1A & 1B are identical to FIGS. 1A & 1B :
  • System 100 is floating in a body of water 120 having surface 122 and floor 124 .
  • system 100 includes buoyant columns 102 connected at their base by buoyant pontoon members 104 , and connected at their top by deck 106 .
  • Drilling equipment 108 as is known in the art may be disposed on deck 106 .
  • Heave plates 110 are fixed to the base of columns 102 , and may optionally be attached to pontoon members 104 .
  • Anchor lines 112 are connected to the base of columns 102 and to anchors (not shown) on floor 124 .
  • Conduit 116 such as a riser or umbilical, connects equipment 114 at floor 124 to dry tree 134 on deck 106 .
  • Equipment 114 could be a wellhead, liner hanger, subsea BOP, manifold, pump, separator, or other equipment as is known in the art.
  • plates 110 there are four plates 110 . In other embodiments, there could be from 2 to about 8 plates, for example from about 4 to about 6 plates. Plates 110 could be attached to every column 102 , or every other column 102 . Although plates 110 are shown as circular plates, in other embodiments, plates 110 could be oval, square, diamond, rectangular, triangular, pentagonal, hexagonal, octagonal, or other polygonal shaped plates, for example polygonal shaped plates having from about 3 to about 10 sides, for example from about 4 to 8 sides.
  • anchor lines 112 , 2 connected to each column 102 .
  • conduit 116 As shown in FIG. 1B , only one conduit 116 is illustrated. In other embodiments, there could be from about 1 to about 20 conduits, for example from about 4 to about 10 conduits. Conduits could be top tensioned risers, drilling conduits, or other conduits as are known in the art.
  • conduit 116 may be a top tensioned riser connected a tensioner (not shown) located on deck 106 .
  • Tensioner may have a stroke range from about 5 to about 50 feet, for example from about 10 to about 28 feet.
  • columns 102 are illustrated having a circular cross section. In other embodiments, columns 102 may have a square, rectangular, oval, triangular, or other shaped cross section.
  • columns 102 have a diameter from about 10 to about 80 feet, for example from about 20 to 60 feet, or from about 40 to about 50 feet.
  • columns 102 have a length from about 50 to about 200 feet, for example from about 75 to 150 feet, or from about 100 to about 125 feet.
  • the spacing between adjacent columns 102 is from about 75 to about 400 feet, for example from about 100 to 300 feet, or from about 150 to about 200 feet.
  • plates 110 have a diameter from about 20 to about 200 feet, for example from about 40 to 150 feet, or from about 50 to about 100 feet.
  • system 100 has a draft (submerged portion) from about 50 to about 200 feet, for example from about 60 to 150 feet, or from about 75 to about 125 feet.
  • system 100 has a displacement from about 10,000 to about 80,000 tons, for example from about 20,000 to about 70,000 tons, or from about 30,000 to about 60,000 tons.
  • FIG. 1C
  • FIG. 1C a close up view of one column 102 and plate 110 is shown, where the column 102 is connected to two pontoons 104 .
  • Plate 110 is attached to inner 130 , middle 132 , and outer 134 circumferential support beams. Plate 110 is also attached to radial support beams 140 .
  • Plate 110 is shown with a square shape, but other shapes are also suitable, as discussed above.
  • FIG. 2
  • system 200 is illustrated.
  • System 200 is floating in a body of water 220 having surface 222 and floor 224 .
  • system 200 includes buoyant columns 202 connected above their base by buoyant pontoon members 204 , and connected at their top by deck 206 .
  • Various equipment 208 such as drilling equipment and production equipment as is known in the art may be disposed on deck 206 .
  • Heave plates 210 are fixed to the base of columns 202 , and are further attached to columns with angled beams 250 .
  • Anchor lines 212 are connected to the base of columns 202 and to anchors (not shown) on floor 224 .
  • Conduit 216 such as a riser or umbilical, connects equipment 214 at floor 224 to dry tree 234 located above the water surface and below deck 206 .
  • Equipment 214 could be a wellhead, subsea BOP, manifold, pump, separator, or other equipment as is known in the art.
  • FIG. 3 is a diagrammatic representation of FIG. 3 :
  • system 300 is illustrated.
  • System 300 is floating in a body of water 320 having surface 322 and floor 324 .
  • system 300 includes buoyant columns 302 connected at their base by buoyant pontoon members 304 , and connected at their top by deck 306 .
  • Various equipment 308 as is known in the art may be disposed on deck 306 .
  • Heave plates 310 are fixed above the base of columns 302 , and are further attached to columns with angled beams 350 .
  • Anchor lines 312 are connected to the base of columns 302 and to anchors (not shown) on floor 324 .
  • Conduit 316 such as a riser or umbilical, connects equipment 314 at floor 324 to dry tree 334 located near deck 306 .
  • FIGS. 4 a - 4 b
  • System 400 is illustrated.
  • System 400 is floating in a body of water 420 having surface 422 and floor 424 .
  • system 400 includes buoyant columns 402 connected at their base by buoyant pontoon members 404 , and connected at their top by deck 406 .
  • Various equipment 408 as is known in the art may be disposed on deck 406 .
  • Heave plates 410 are fixed to column extenders 360 located within the base of columns 402 .
  • Anchor lines 412 are connected to the base of columns 402 and to anchors (not shown) on floor 424 .
  • Conduit 416 such as a riser or umbilical, connects equipment 414 at floor 424 to dry tree 434 located near deck 406 .
  • column extenders 360 are located within the base of columns 402 , such as when system is going to be transported from the dock to an installation location, or from the installation location back to the dock.
  • column extenders 460 have been lowered from within the base of columns 402 , to place plates 410 at a greater depth below the water surface, for example at a depth of 100 to 300 feet below the water surface.
  • connector 462 may be provided to connect and provide structural support to column extenders 460 .
  • Connector 462 may be a beam, cable, rope, pontoon, or other structures as are known in the art.
  • Connector 462 may be attached to column extenders 460 when column extenders 360 are located within the base of columns 402 , or connector 462 may be attached to column extenders 460 after column extenders 460 have been lowered from within the base of columns 402 .
  • system 100 has a displacement of at least about 20,000 tons, for example from about 25,000 to 150,000 tons, or from about 30,000 to 100,000, or from about 35,000 to 50,000 tons.
  • a floating system comprising a plurality of buoyant columns, a top portion of the columns extending above a water surface, and a bottom portion of the columns submerged in a body of water; a deck connected to the top portion of the columns; at least one pontoon connected to the bottom portion of at least two of the columns; a plurality of heave plates, each heave plate connected to the bottom portion of at least one of the columns; and a conduit connected to the deck and extending to a bottom of the body of water.
  • the system also includes drilling equipment on the deck.
  • the system also includes anchor lines connected to the bottom portion of at least two of the columns
  • the conduit comprises a top tensioned riser.
  • the system also includes a dry tree connected to a top end of the conduit, the dry tree installed above the water surface.
  • the pontoons are buoyant.
  • the plurality of buoyant columns comprises from 3 to 6 buoyant columns
  • the system has a displacement of at least about 25,000 tons.
  • the system also includes supporting beams, each beam connected to the heave plate and the buoyant column
  • the pontoon is connected to the column above a location of the heave plate.
  • the pontoon is connected to the column below a location of the heave plate.
  • the system also includes at least one telescopic column extenders connected to the column at a first end and the heave plate at a second end.
  • the telescopic column extenders are extendable from a first position at least partially within the column to a second position outside the column.
  • the system also includes a column extender stabilizer connected to at least two of the column extenders.

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  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Ocean & Marine Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Structural Engineering (AREA)
  • Civil Engineering (AREA)
  • Architecture (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Earth Drilling (AREA)
  • Toys (AREA)
  • Removal Of Floating Material (AREA)
  • Wind Motors (AREA)
US13/383,438 2009-07-13 2010-07-06 Semi-submersible floating structure Abandoned US20120114421A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US13/383,438 US20120114421A1 (en) 2009-07-13 2010-07-06 Semi-submersible floating structure

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US22495909P 2009-07-13 2009-07-13
PCT/US2010/041048 WO2011008590A1 (en) 2009-07-13 2010-07-06 Semi-submersible floating structure
US13/383,438 US20120114421A1 (en) 2009-07-13 2010-07-06 Semi-submersible floating structure

Publications (1)

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US20120114421A1 true US20120114421A1 (en) 2012-05-10

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US13/383,438 Abandoned US20120114421A1 (en) 2009-07-13 2010-07-06 Semi-submersible floating structure

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US (1) US20120114421A1 (no)
BR (1) BR112012000785A2 (no)
NO (1) NO20120012A1 (no)
WO (1) WO2011008590A1 (no)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160318585A1 (en) * 2014-01-17 2016-11-03 Connect Lng As A transfer structure, a transfer system and a method for transferring lng and/or electric power
CN108163158A (zh) * 2018-01-08 2018-06-15 上海交通大学 一种可伸缩式垂荡板导流罩装置
CN109799066A (zh) * 2019-01-22 2019-05-24 中国海洋石油集团有限公司 一种可调节垂荡板深度的半潜式平台水池试验装置
US10358188B2 (en) 2016-11-09 2019-07-23 Horton Do Brasil Technologia Offshore, Ltda. Floating offshore structures with round pontoons

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3397545A (en) * 1965-10-11 1968-08-20 Ingalls Shipbuilding Corp Marine structure
US4435108A (en) * 1981-08-11 1984-03-06 Sedco, Inc. Method of installing sub-sea templates
US5421676A (en) * 1993-02-08 1995-06-06 Sea Engineering Associates, Inc. Tension leg platform and method of instalation therefor
US6564741B2 (en) * 2001-06-01 2003-05-20 The Johns Hopkins University Telescoping spar platform and method of using same
US20040037651A1 (en) * 2000-06-21 2004-02-26 Khachaturian Jon E. Articulated multiple buoy marine platform apparatus and method of installation
US6945737B1 (en) * 2004-02-27 2005-09-20 Technip France Single column extendable draft offshore platform
US7037044B2 (en) * 2003-10-15 2006-05-02 Technip France Deck-to-column connection for extendable draft platform
US7191836B2 (en) * 2004-08-02 2007-03-20 Kellogg Brown & Root Llc Dry tree subsea well communications apparatus and method using variable tension large offset risers
US20070166109A1 (en) * 2006-01-13 2007-07-19 Yun Ding Truss semi-submersible offshore floating structure

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7086809B2 (en) * 2003-01-21 2006-08-08 Marine Innovation & Technology Minimum floating offshore platform with water entrapment plate and method of installation

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3397545A (en) * 1965-10-11 1968-08-20 Ingalls Shipbuilding Corp Marine structure
US4435108A (en) * 1981-08-11 1984-03-06 Sedco, Inc. Method of installing sub-sea templates
US5421676A (en) * 1993-02-08 1995-06-06 Sea Engineering Associates, Inc. Tension leg platform and method of instalation therefor
US20040037651A1 (en) * 2000-06-21 2004-02-26 Khachaturian Jon E. Articulated multiple buoy marine platform apparatus and method of installation
US6564741B2 (en) * 2001-06-01 2003-05-20 The Johns Hopkins University Telescoping spar platform and method of using same
US7037044B2 (en) * 2003-10-15 2006-05-02 Technip France Deck-to-column connection for extendable draft platform
US6945737B1 (en) * 2004-02-27 2005-09-20 Technip France Single column extendable draft offshore platform
US7191836B2 (en) * 2004-08-02 2007-03-20 Kellogg Brown & Root Llc Dry tree subsea well communications apparatus and method using variable tension large offset risers
US20070166109A1 (en) * 2006-01-13 2007-07-19 Yun Ding Truss semi-submersible offshore floating structure
US7871222B2 (en) * 2006-01-13 2011-01-18 J. Ray Mcdermott, S.A. Truss semi-submersible offshore floating structure

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160318585A1 (en) * 2014-01-17 2016-11-03 Connect Lng As A transfer structure, a transfer system and a method for transferring lng and/or electric power
US10532796B2 (en) * 2014-01-17 2020-01-14 Connect Lng As Transfer structure, a transfer system and a method for transferring LNG and/or electric power
US10358188B2 (en) 2016-11-09 2019-07-23 Horton Do Brasil Technologia Offshore, Ltda. Floating offshore structures with round pontoons
US11084553B2 (en) 2016-11-09 2021-08-10 Horton Do Brasil Technologia Offshore, Ltda. Floating offshore structures with round pontoons
CN108163158A (zh) * 2018-01-08 2018-06-15 上海交通大学 一种可伸缩式垂荡板导流罩装置
CN109799066A (zh) * 2019-01-22 2019-05-24 中国海洋石油集团有限公司 一种可调节垂荡板深度的半潜式平台水池试验装置

Also Published As

Publication number Publication date
NO20120012A1 (no) 2012-01-06
WO2011008590A1 (en) 2011-01-20
BR112012000785A2 (pt) 2016-02-23

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Owner name: SHELL OIL COMPANY, TEXAS

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:VAN DEN HAAK, ARNO LAURENTIUS MICHAEL;LI, YILE;LI, YOU SUN;AND OTHERS;SIGNING DATES FROM 20111121 TO 20111122;REEL/FRAME:027513/0832

STCB Information on status: application discontinuation

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