WO2008067406A2 - Système de corps mort de passe-coque - Google Patents

Système de corps mort de passe-coque Download PDF

Info

Publication number
WO2008067406A2
WO2008067406A2 PCT/US2007/085797 US2007085797W WO2008067406A2 WO 2008067406 A2 WO2008067406 A2 WO 2008067406A2 US 2007085797 W US2007085797 W US 2007085797W WO 2008067406 A2 WO2008067406 A2 WO 2008067406A2
Authority
WO
WIPO (PCT)
Prior art keywords
hull
ballasted
mono
hawspipe
column
Prior art date
Application number
PCT/US2007/085797
Other languages
English (en)
Other versions
WO2008067406A3 (fr
Inventor
Bruce Keener
Original Assignee
Transocean Sedco Forex Ventures Limited
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 Transocean Sedco Forex Ventures Limited filed Critical Transocean Sedco Forex Ventures Limited
Priority to CA002670847A priority Critical patent/CA2670847A1/fr
Publication of WO2008067406A2 publication Critical patent/WO2008067406A2/fr
Publication of WO2008067406A3 publication Critical patent/WO2008067406A3/fr
Priority to NO20092161A priority patent/NO20092161L/no

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B21/00—Tying-up; Shifting, towing, or pushing equipment; Anchoring
    • B63B21/50—Anchoring arrangements or methods for special vessels, e.g. for floating drilling platforms or dredgers
    • 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
    • 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
    • B63B2035/442—Spar-type semi-submersible structures, i.e. shaped as single slender, e.g. substantially cylindrical or trussed vertical bodies

Definitions

  • the invention relates to a system for mooring a floating platform in an ice flow. Mooring a platform in an ice flow requires the mooring lines to penetrate the ice flow. At least three issues are important to a mooring system designed for ice flow. First, the mooring system must not adversely effect the stability of the platform. Second, the mooring lines must be protected from the ice flow. Third, the mooring system must be accessible for inspection.
  • a central concept the stability of a floating platform is the metacentric height.
  • the metacentric height is the vertical distance from the center of gravity of the platform to its metacenter.
  • Mooring lines are pulled in a played out using winches. Often, the winches are placed on or near the deck of the platform, above the waterline. In this position, the mooring lines extend from the deck to the seabed. In ice flow, mooring lines must be protected as they penetrate the ice flowing around the platform.
  • Inspecting a mooring system must be periodically inspected. To inspect a mooring system, an inspector must have access to the entire system. To do this, the entire mooring system must close enough to the surface that it can be raised out of the water for inspection.
  • the inventive mooring system guides mooring line through the moonpool to a water depth below the ice flow and then penetrates through the hull above lower ballasting tanks.
  • the invention includes different embodiments.
  • the invention can be described as a floating platform that includes a mono-column hull with a moonpool, a winch supported by the mono-column hull, a hawspipe with an inner end open to the moonpool and an outer end open to the exterior of the mono-column hull, wherein the outer end of the hawspipe is below the operational waterline of the mono-column hull, an outer fairlead positioned relative to the outer end of the hawspipe, and a mooring line extending from the winch and through the hawspipe and the outer fairlead.
  • the outer fairlead may below the center of gravity of the mono-column hull.
  • the water lever the mooring line exits the hull is defined by the hawspipe.
  • the hawspipe is positioned below the depth of an ice flow when the mono-column hull is ballasted for drilling operations.
  • the outer end of the hawspipe is ideally above the waterline when the mono-column hull is deballasted.
  • the outer fairlead may final contact the mooring line has with the hull as it extends to the seabed.
  • the mono-column hull may include ballast tanks that are located below the hawspipe.
  • the mono-column hull may also include an ice flow zone and a ballast zone.
  • the outer end of the hawspipe may be in the ballast zone.
  • the mooring line may extend through the moonpool in the ice flow zone.
  • the inner end of the hawspipe is positioned adjacent the ice flow zone and the ballast zone of the mono-column hull.
  • the invention may include a floating platform that comprises a ballasted hull with a channel extending therethrough, which channel may be a moonpool, and ballasted hull has an operational waterline when ballasted for drilling operations and a deballasted waterline, a hawspipe connecting the channel with the outside of the ballasted hull, a winch supported by the ballasted hull, an inner fairlead connected to the ballasted hull and operationally aligned with the winch, and an outer fairlead connected to the ballasted hull and positioned between the operational waterline and the deballasted waterline of the ballasted hull, wherein the inner fairlead and the outer fairlead are in operable alignment with the hawspipe.
  • the outer fairlead may be positioned to transfers mooring forces to the ballasted hull as close to the center of gravity as possible. Further, the outer fairlead may be positioned below the depth of ice when the hull in a ballasted for drilling operations.
  • the ballasted hull of the second embodiment may include an ice flow section shaped to minimize the force from ice flowing past the floating platform and a ballasted section below the ice flow section, wherein the ballasted section is below the ice when the floating platform is ballasted for drilling operations.
  • the hawspipe may be above the center of buoyancy of the floating platform when ballasted for normal drilling operations.
  • the floating platform may include a second ballasted hull with a channel extending therethrough, wherein the second ballasted hull has an operational waterline when ballasted for drilling operations and an deballasted waterline, a second hawspipe connecting the channel of the second ballasted hull with the outside of the second ballasted hull, a second winch supported by the second ballasted hull, an second inner fairlead connected to the second ballasted hull and longitudinally aligned with the second winch, and a second outer fairlead connected to the second ballasted hull and positioned between the ballasted waterline and the un-ballasted waterline of the second ballasted hull; wherein the second inner fairlead and the second outer fairlead are in operable alignment with the second hawspipe.
  • the invention can also be described as a system for mooring a floating platform.
  • the system includes a mono-column hull and a moonpool extending therethrough, the mono-column hull having a deballasted waterline and a range of operational waterlines above the deballasted waterline, a mooring winch supported by the mono- column hull, an inner fairlead positioned in the moonpool of the mono-column hull, a hawspipe between the moonpool and the exterior of the mono-column hull; wherein the hawspipe opens to the exterior of the mono-column hull above the deballasted waterline, and an outer fairlead connected to the exterior of the mono-column hull adjacent to the hawspipe.
  • the winch of the mooring system can be cantilevered over the moonpool of the mono-column hull.
  • the mooring line can be lowered directly to the inner fairlead or hawspipe.
  • the inner and outer fairleads of the mooring system can be operationally aligned with the hawspipe. Such an operational alignment may be in a straight line.
  • the mono-column hull of the mooring system includes a center of gravity and a deballasted center of buoyancy, and the hawspipe may be positioned to exit the mono- column hull above the deballasted center of buoyancy. Further, the hawspipe is positioned above ballasting tanks.
  • the mono-column hull of the mooring system also includes a deballasted waterline, and wherein the hawspipe exits the mono-column hull above the deballasted waterline.
  • the point at which the mooring line exits the mono-column hull is optimally below the ice-flow zone.
  • FIG. 1 is a is a side view of a floating platform according to the invention.
  • FIG. 2 is a section view of the platform in FIG. 1 ;
  • FIG. 3 shows the platform in FIG. 1 during a roll/pitch motion
  • FIG. 4 shows the platform in FIG. 1 with drilling equipment
  • FIG. 1 shows a floating platform (10) for offshore drilling or production of hydrocarbons, comprising a topside (11) equipped with non-illustrated drilling and/or production equipment, and a substructure (12) which comprises a mono-column hull (13) supporting topside (11).
  • Platform (10) is in sea (14) and has an operational waterline (15) when ballasted for drilling or production operations.
  • Operational waterline (15) varies depending on the type of operation, weather, and sea state.
  • When platform (10) is deballasted is has a deballasted waterline (15').
  • the topside (11) may comprise one or more decks, and in addition to the drilling and/or production equipment, may also comprise equipment and installations for carrying out a number of functions that are necessary in connection with a floating platform, for example, living quarters, hoisting cranes and electric generators.
  • the mono-hull is provided with non-illustrated buoyancy tanks and ballast water tanks extending generally the length of the hull which can be filled with water in order to adjust the position of the platform in the sea 14.
  • Mono-column (13) includes an ice flow zone (16) shaped to minimize the force exerted on floating platform (10) by an ice-flow.
  • ice flow zone (16) has a circular cross-section. The length of ice flow zone (16) is based in part on the expected thickness of the ice flow. It is also based on the expected sea state.
  • Floating platform (10) includes mooring winches (18) positioned next to a moonpool (19). In the embodiment shown, mooring winches (18) are cantilevered over moonpool (19).
  • winches (18) are shown on topside (11), they may be positioned in any dry location. For example, the winches may be positioned inside the hull and below the water line. Mooring winches (18) retrieve and pay-out mooring lines through moonpool (19).
  • the mooring lines are guided inside moonpool (19) by inner fairleads (20). Although one inner fairlead (20) is shown per mooring line, any number can be used.
  • the inner fairlead (20) guides the mooring line as close as practical to the inner wall of moonpool (19).
  • the inner fairleads (20) also guide the mooring lines into hawspipes (21).
  • Hawspipes (21) extend through mono-column hull (13) to outer fairleads (22). Hawspipes (21) are shown at a downward angle. However, hawspipes (21) may be at any angle. Hawspipes (21) are shown extending from moonpool (19) to the exterior of mono-column hull (13). In an alternative embodiment, hawspipes (21) extend between a non-ice area to the exterior. For example, mooring lines may be run inside the walls of mono-column hull (13) instead of moonpool (19). In such an embodiment, hawspipes (21) would extend from the interior area to the exterior of mono-column hull (13). Multiple mooring lines may be run through a single hawspipe (21) or each mooring line may have its own hawspipe (21).
  • Outer fairleads (22) guide the mooring lines to anchor points on the seabed. Outer fairleads (22) are aligned with hawspipes (21). Outer fairleads (22) are positioned below the ice flow.
  • hawspipes (21) and outside fairleads (22) are positioned above the deballasted waterline (15').
  • Floating platform (10) has a center of gravity (G), a center of buoyancy (B), and a metacenter (M). These points are discussed in more detail below. Arrows indicating the weight and buoyancy of floating platform (10) are shown.
  • Platform (10) may be connected to the seabed by means slanting, slack moorings, or it may be held almost stationary in the sea by means of dynamic positioning, with the aid of thrusters that are controlled by an electronic control system.
  • the forces on platform (10) are shown extending from the outside fairleads (22).
  • Mono-column hull (13) has a central axis (23).
  • FIGS. 1 and 2 show floating platform (10) in the sea without any external influences. In this neutral position, the platform's central axes (23) is vertical and the center of gravity (G) and center of buoyancy (B) are aligned.
  • FIG. 3 shows the platform (10) during a roll/pitch, where platform (10) has been turned in the direction Pl.
  • the position of the waterline when the platform is ballasted for normal operations, seen in relation to platform (10), is indicated by reference numeral (15). It can be seen that portions of platform (10) to the right are above waterline (15), while portions of the platform to the left are below waterline (15).
  • the platform's center of buoyancy is defined by the center of gravity of the water the platform displaces. Thus, when the platform rolls, the center of buoyancy, seen in relation to platform (10), moves from position B to B'.
  • metacenter (M) a vertical line from the new center of buoyancy (B') intersects central axis (23) defines metacenter (M).
  • B' new center of buoyancy
  • Pl central axis
  • the center of gravity (G) of the platform is a function of the platform's mass and the distribution of the mass. Accordingly, it is constant and independent of the platform's buoyancy and position in the sea. The center of gravity (G) does not move from central axis (23) during platform motion.
  • the metacentric height is an important parameter for the natural frequency of roll and pitch motion.
  • the longer the stability arm the distance between center of gravity (G) and metacenter (M), the greater will be the moment generated by the buoyancy of the structure tending to return the structure to the neutral position.
  • G center of gravity
  • M metacenter
  • FIGS. 1 and 3 show mooring lines attached to floating platform (10). Mooring lines impact platform stability by imparting additional restoring moments that add to that produced by the displacement of the center of buoyancy. As a result of the additional restoring moment, the apparent stability arm is increased. [0040] To minimize the additional restoring moment from mooring lines, outer fairleads (22) are positioned below the center of gravity (G). Preferably, the outer fairleads (22) are between the center of gravity (G) and the center of buoyancy (B).

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • Ocean & Marine Engineering (AREA)
  • Architecture (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Earth Drilling (AREA)
  • Catching Or Destruction (AREA)
  • Foundations (AREA)

Abstract

L'invention concerne un système de corps mort pour une plate-forme de flottaison qui comprend un manchon d'écubier positionné sous le niveau de la mer lorsque la plate-forme est ballastée pour des opérations normales. Le système comprend également un chaumard externe qui guide une ligne de corps mort depuis la plate-forme de flottaison vers un point d'ancrage sur le fond marin. Le chaumard externe est positionné par rapport au centre de gravité de la plate-forme flottante et au centre de flottaison de celle-ci. Le chaumard externe est également positionné pour être au-dessus de la ligne de flottaison déballastée.
PCT/US2007/085797 2006-11-28 2007-11-28 Système de corps mort de passe-coque WO2008067406A2 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CA002670847A CA2670847A1 (fr) 2006-11-28 2007-11-28 Systeme de corps mort de passe-coque
NO20092161A NO20092161L (no) 2006-11-28 2009-06-04 Fortoyningssystem gjennom skroget

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US86753006P 2006-11-28 2006-11-28
US60/867,530 2006-11-28

Publications (2)

Publication Number Publication Date
WO2008067406A2 true WO2008067406A2 (fr) 2008-06-05
WO2008067406A3 WO2008067406A3 (fr) 2008-09-18

Family

ID=39468695

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2007/085797 WO2008067406A2 (fr) 2006-11-28 2007-11-28 Système de corps mort de passe-coque

Country Status (5)

Country Link
US (1) US20080121163A1 (fr)
CA (1) CA2670847A1 (fr)
NO (1) NO20092161L (fr)
RU (1) RU2009124445A (fr)
WO (1) WO2008067406A2 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010008302A1 (fr) * 2008-07-16 2010-01-21 Aker Pusnes As Équipement d’amarrage
US8047151B2 (en) 2008-08-01 2011-11-01 Keppel Offshore & Marine Technology Centre Pte Ltd System and method for mooring of offshore structures
ES2396783A1 (es) * 2011-03-07 2013-02-26 Investigación Y Desarrollo De Energías Renovables Marinas, S.L. Plataforma meteorológica flotante.
KR101540336B1 (ko) * 2013-10-04 2015-07-30 삼성중공업 주식회사 해양부유구조물

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7958835B2 (en) * 2007-01-01 2011-06-14 Nagan Srinivasan Offshore floating production, storage, and off-loading vessel for use in ice-covered and clear water applications
SE534498C2 (sv) * 2010-02-05 2011-09-13 Gva Consultants Ab Permanent lägeshållningssystem för flytande enhet
CN109444364A (zh) * 2018-11-09 2019-03-08 苏州煜水生物科技有限公司 一种水质在线监测平台固定装置

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3739736A (en) * 1971-07-29 1973-06-19 Gen Dynamics Corp Mooring system for drilling hull in arctic waters
US3880102A (en) * 1974-02-19 1975-04-29 Offshore Technology Corp Method and apparatus for offshore submersible oil storage and drilling
US6106198A (en) * 1996-02-16 2000-08-22 Petroleum Geo-Services As Method for installation of tension-leg platforms and flexible tendon
US7377255B2 (en) * 2005-01-04 2008-05-27 Toyota Jidosha Kabushiki Kaisha Dual injection type internal combustion engine

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3191201A (en) * 1962-04-02 1965-06-29 Offshore Co Mooring system
US3774562A (en) * 1972-06-12 1973-11-27 Global Marine Inc 360{20 {11 rotary anchoring system with differential drive capability
US4701143A (en) * 1984-10-17 1987-10-20 Key Ocean Services, Inc. Vessel mooring system and method for its installation
US6431107B1 (en) * 1998-04-17 2002-08-13 Novellant Technologies, L.L.C. Tendon-based floating structure
US6371697B2 (en) * 1999-04-30 2002-04-16 Abb Lummus Global, Inc. Floating vessel for deep water drilling and production
US6854933B2 (en) * 2002-08-07 2005-02-15 Deepwater Technologies, Inc. Vertically restrained centerwell SPAR
US7104214B2 (en) * 2003-10-03 2006-09-12 Hydralift Amclyde, Inc. Fairlead with integrated chain stopper
US7377225B2 (en) * 2006-08-07 2008-05-27 Technip France Spar-type offshore platform for ice flow conditions

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3739736A (en) * 1971-07-29 1973-06-19 Gen Dynamics Corp Mooring system for drilling hull in arctic waters
US3880102A (en) * 1974-02-19 1975-04-29 Offshore Technology Corp Method and apparatus for offshore submersible oil storage and drilling
US6106198A (en) * 1996-02-16 2000-08-22 Petroleum Geo-Services As Method for installation of tension-leg platforms and flexible tendon
US7377255B2 (en) * 2005-01-04 2008-05-27 Toyota Jidosha Kabushiki Kaisha Dual injection type internal combustion engine

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010008302A1 (fr) * 2008-07-16 2010-01-21 Aker Pusnes As Équipement d’amarrage
NO329857B1 (no) * 2008-07-16 2011-01-17 Aker Pusnes As Fortoyningsarrangement
US8544400B2 (en) 2008-07-16 2013-10-01 Aker Pusnes As Mooring arrangement
US8047151B2 (en) 2008-08-01 2011-11-01 Keppel Offshore & Marine Technology Centre Pte Ltd System and method for mooring of offshore structures
ES2396783A1 (es) * 2011-03-07 2013-02-26 Investigación Y Desarrollo De Energías Renovables Marinas, S.L. Plataforma meteorológica flotante.
KR101540336B1 (ko) * 2013-10-04 2015-07-30 삼성중공업 주식회사 해양부유구조물

Also Published As

Publication number Publication date
WO2008067406A3 (fr) 2008-09-18
CA2670847A1 (fr) 2008-06-05
NO20092161L (no) 2009-06-04
US20080121163A1 (en) 2008-05-29
RU2009124445A (ru) 2011-01-10

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