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WO1999005389A1 - Systeme flottant pour un tube goulotte - Google Patents

Systeme flottant pour un tube goulotte Download PDF

Info

Publication number
WO1999005389A1
WO1999005389A1 PCT/US1998/015200 US9815200W WO9905389A1 WO 1999005389 A1 WO1999005389 A1 WO 1999005389A1 US 9815200 W US9815200 W US 9815200W WO 9905389 A1 WO9905389 A1 WO 9905389A1
Authority
WO
WIPO (PCT)
Prior art keywords
modules
riser
buoyancy
flotation system
assemblies
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.)
Ceased
Application number
PCT/US1998/015200
Other languages
English (en)
Inventor
Lou W. Watkins
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.)
Cuming Corp
Original Assignee
Cuming Corp
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 Cuming Corp filed Critical Cuming Corp
Priority to AU85807/98A priority Critical patent/AU8580798A/en
Publication of WO1999005389A1 publication Critical patent/WO1999005389A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • 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
    • B63B39/005—Equipment to decrease ship's vibrations produced externally to the ship, e.g. wave-induced vibrations
    • 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
    • B63B21/502—Anchoring arrangements or methods for special vessels, e.g. for floating drilling platforms or dredgers by means of tension legs
    • 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
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
    • E21B17/01—Risers
    • E21B17/012—Risers with buoyancy elements
    • 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
    • B63B21/502—Anchoring arrangements or methods for special vessels, e.g. for floating drilling platforms or dredgers by means of tension legs
    • B63B2021/504—Anchoring arrangements or methods for special vessels, e.g. for floating drilling platforms or dredgers by means of tension legs comprising suppressors for vortex induced vibrations
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B2231/00—Material used for some parts or elements, or for particular purposes
    • B63B2231/70—Glass
    • B63B2231/72—Hollow glass microspheres

Definitions

  • This invention relates generally to marine risers connecting submerged well heads to floating drilling rigs, and is concerned in particular with a flotation system for such risers.
  • syntactic foam buoyancy modules are employed to impart buoyant lift to the steel riser pipe, thereby eliminating most of the weight of the riser in sea water.
  • the goal is to offset as much of the riser weight as possible without making the riser positively buoyant, which could lead to a dangerous condition.
  • the target is to provide buoyancy equal to about 95% -98% of the riser weight in sea water. This enables safe operation of the drill rig in all kinds of sea states without undue wear and tear on its riser support mechanisms.
  • the major constraints on the amount of buoyancy that can be provided are (1) the density of the syntactic foam, which must necessarily increase as the water depth increases, and (2) the diameter of the opening in the rotary table on the drilling rig, through which the riser and its attached buoyancy modules must be lowered.
  • syntactic foam density ranges from 26.0 lbs per cubic foot at a depth of 2,000 feet to 36.0 lbs per cubic foot at 10,000 feet.
  • Rotary table diameter openings are standardized at 39.50", 49.50", and 60.00". In today's increasing water depths, it is often difficult to provide as much buoyancy as the drilling engineer requires, and the rig operator must therefore compromise between safety margins and operating efficiencies over a wide range of conditions.
  • the present invention is an improvement whereby the buoyancy modules are integrally shaped externally to reduce VIV formation in a way analogous to the strakes referred to above.
  • the shaped modules are configured and dimensioned to pass intact through the rotary table, so that no time-consuming assembly or disassembly on board the drilling rig is required. Integral molding of the VIV interfering shapes does not add appreciable cost to the system.
  • the integrally molded shaped externally modules of the present invention are inherently less volumetrically efficient, suffering a reduction of 20% to 30% less volume than conventional cylindrical modules of the same external diameter. This loss in volume is reflected in an equivalent reduction in buoyancy.
  • the present invention obviates this problem by taking advantage of the fact that it is not necessary to cover the entire riser string with integrally molded shaped modules in order to effect the desired reduction in VIV.
  • Ocean currents are most often restricted to relatively shallow depths, typically the uppermost 300 to 500 feet. In the case of the deep water wells, this amounts to only about 10% of the total riser length being at risk of damage from currents.
  • the lower density of the uppermost modules can be used to advantage to offset some if not all of the buoyancy deficit resulting from their non-cylindrical contours.
  • overall buoyancy loss with a system according to the present invention will be only 2.0 to 3.0% less than that which might otherwise be achieved with conventional systems.
  • Figure 1 is a somewhat diagrammatic illustration, not to scale, of a drilling installation with a marine riser flotation system in accordance with the present invention
  • Figure 2 is a three dimensional view of conventional cylindrical buoyancy modules
  • FIG 3 is a horizontal sectional view through the buoyancy modules shown in Figure 2;
  • Figure 4 is a three dimensional view of a buoyancy module in accordance with the present invention.
  • FIG. 5 is a horizontal sectional view through the buoyancy module of Figure 4.
  • Figure 6 is a side view looking upwardly with respect to Figure 5;
  • Figure 7 is a side view at 90° with respect to Figure 6.
  • a marine riser flotation system is generally depicted at 10.
  • the flotation system is used to encase and impart buoyant lift to a riser string extending downwardly from a drilling rig 12 floating on the ocean surface to a submerged well head 14 at the ocean floor.
  • module halves 16a, 16b encase the drill pipe 18 and its associated service conduits 20, 22.
  • the module halves are secured together by external straps 24, and are externally configured to provide a cylindrical exterior surface exposed to the surrounding water.
  • the riser string is exposed to ocean currents which are most often restricted to relatively shallow depths, typically the uppermost 300- 500 ft as indicated at 26 in Figure 1.
  • vortices 28 see Figure 3
  • the external shape of the module halves 30a, 30b are changed from simple cylinders to a new geometry which prevents the formation of regular and repetitive streets of vortices.
  • the new shape is kept as close as possible to the prior art cylindrical configuration so as to conserve volumetric displacement.
  • the new external shape defines a twisted hexagon having six flat sides , each of which twists to thereby define a helical facet 32.
  • the six helical facets are tangent to an inner reference circle 34 and comprise chords of an outer reference circle 36, with the inner and outer reference circles being concentric with respect to a common central axis "A".
  • the facets 32 extend helically with respect to the axis A.
  • the diameter of the inner reference circle 34 is preferably about 80-90% of the diameter of the outer reference circle 36.
  • the twisted configuration of the facets 32 staggers the formation of vortices
  • any number between about 5 to 8 should operate satisfactorily.
  • the helical angle of twist of the facets should preferably be about 3-6°, with the helically extending facets of successive module assemblies defining continuous helixes extending along the length of the riser encased by the shaped modules.
  • the higher syntactic foam densities of the module 16a, 16b is offset by the greater volume afforded by their cylindrical configurations.
  • the decreased volumes of the uppermost modules 30a, 30b is also offset by their relatively lower syntactic foam densities.
  • the advantages of the present invention are its inherent simplicity, ruggedness and economy. Integrally molding vortex-shedding capability into the external surfaces of the module halves adds a margin of safety and operating latitude to the riser with no extra parts and at little if any extra cost.
  • the new shapes are as rugged as conventional cylindrical shapes, and far more durable than separately applied fragile fairings or strakes. Since no shipboard installation and removal of separate components is involved, valuable rig time is more efficiently utilized.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Ocean & Marine Engineering (AREA)
  • Geology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • Architecture (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Earth Drilling (AREA)

Abstract

Des modules flottants sont formés extérieurement d'un seul tenant pour réduire la formation de vibrations induites par les tourbillons. Les modules formés sont configurés et dimensionnés pour passer en restant intacts dans une table de rotation, ce qui évite toute opération longue d'assemblage ou de démontage à bord d'une plate-forme de forage. Le moulage d'un seul tenant des formes interférant avec les vibrations induites par les tourbillons n'augmente pas le coût du système. Les modules moulés selon la présente invention présentent un rendement volumétrique moindre, et un volume de 20 à 30 % inférieur à celui des modules cylindriques traditionnels de même diamètre extérieur. Cette perte de volume se traduit par une réduction similaire de la flottabilité. La présente invention permet de résoudre ce problème en tirant profit du fait qu'il n'est pas nécessaire de couvrir la totalité de la colonne de tubes goulottes avec les modules formés selon l'invention pour réduire les vibrations induites par les tourbillons. Les courants océaniques sont souvent restreints à des fonds relativement profonds, en général de 300 à 500 pieds. Dans le cas de puits de grands fonds, cela signifie que 10 % seulement de la longueur totale du tube goulotte risquent d'être endommagés par les courants. Dans bon nombre de cas, la plus faible densité des modules supérieurs peut être utilisée de manière avantageuse pour compenser une partie, voire même la totalité, du manque de flottabilité due aux profils non cylindriques. Ainsi, même dans les cas les plus extrêmes, la perte de flottabilité globale avec le système selon la présente invention ne sera inférieure que de 2,0 à 3,0 % à celle que l'on aurait obtenue avec les systèmes traditionnels.
PCT/US1998/015200 1997-07-23 1998-07-23 Systeme flottant pour un tube goulotte Ceased WO1999005389A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU85807/98A AU8580798A (en) 1997-07-23 1998-07-23 A floating system for a marine riser

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US5352597P 1997-07-23 1997-07-23
US60/053,525 1997-07-23

Publications (1)

Publication Number Publication Date
WO1999005389A1 true WO1999005389A1 (fr) 1999-02-04

Family

ID=21984876

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1998/015200 Ceased WO1999005389A1 (fr) 1997-07-23 1998-07-23 Systeme flottant pour un tube goulotte

Country Status (2)

Country Link
AU (1) AU8580798A (fr)
WO (1) WO1999005389A1 (fr)

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000061433A1 (fr) * 1999-04-08 2000-10-19 Shell Internationale Research Maatschappij B.V. Systeme de reduction de vibration induite par effet vortex sur un element naval
WO2001053651A1 (fr) * 2000-01-24 2001-07-26 Bouygues Offshore Dispositif de liaison fond-surface comportant un dispositif stabilisateur
GB2362444A (en) * 2000-04-10 2001-11-21 Crp Group Ltd Protection of underwater elongate members
WO2002018709A1 (fr) * 2000-08-30 2002-03-07 Crp Group Limited Protection d'elements allonges immerges
WO2002016727A3 (fr) * 2000-08-21 2002-12-12 Cso Aker Maritime Inc Systeme, dispositif et procede de flottabilite de materiel façonne
GB2378493A (en) * 1998-03-07 2003-02-12 Crp Group Ltd Cladding comprising semi-tubular sections with projections
NL1021347C2 (nl) * 2002-08-28 2004-03-02 Lankhorst Special Mouldings B Suppressie-element voor wervelvibraties, bouwpakket, suppressiestelsel, inrichting voor het winnen van delfstoffen en een matrijs.
GB2441534A (en) * 2007-01-17 2008-03-12 Trelleborg Crp Ltd De-correlation rings for vortex induced vibration suppression
WO2009109776A3 (fr) * 2008-03-03 2009-12-03 Trelleborg Crp Limited Moule pour former une gaine sur un élément allongé
WO2010048080A1 (fr) * 2008-10-23 2010-04-29 Shell Oil Company Systèmes et procédés de réduction des vibrations induites par vortex
WO2010126971A3 (fr) * 2009-05-01 2011-02-24 Shell Oil Company Systèmes et procédés pour réduire des vibrations induites par vortex
CN102313638A (zh) * 2011-08-15 2012-01-11 上海交通大学 均匀流下的深海立管分段模型双向强迫振动实验装置
CN102967431A (zh) * 2012-11-06 2013-03-13 上海交通大学 模拟均匀流下深海立管双向自激振动的试验装置
CN102980732A (zh) * 2012-11-06 2013-03-20 上海交通大学 模拟均匀流下深海立管横向自激振动的试验装置
CN104406754A (zh) * 2014-11-25 2015-03-11 上海交通大学 双向强迫振荡状态下的深海细长立管的动力响应测试装置
CN104406753A (zh) * 2014-11-25 2015-03-11 上海交通大学 垂直强迫振荡下的深海细长立管的动力响应测试装置
CN104458174A (zh) * 2014-11-28 2015-03-25 上海交通大学 一种面外均匀流下测量细长立管动力响应装置
CN104483083A (zh) * 2014-12-05 2015-04-01 上海交通大学 模拟海底管土与剪切流的深海细长立管动力响应测试装置
CN104502043A (zh) * 2014-12-02 2015-04-08 上海交通大学 模拟海底管土与水平强迫振荡测量细长立管动力响应装置
CN104458172B (zh) * 2014-11-25 2017-06-13 上海交通大学 一种均匀流下测量细长立管动力响应测试装置
EP2438311A4 (fr) * 2009-06-04 2017-08-16 Diamond Offshore Company Module de flottaison pour colonne montante à virures antivibratoires
US10107048B2 (en) * 2016-09-29 2018-10-23 Ensco International Incorporated Weathervaning riser joint
CN110541677A (zh) * 2019-08-13 2019-12-06 中国石油大学(华东) 一种抑制涡激振动的装置、海洋立管和方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3717113A (en) * 1970-10-19 1973-02-20 Fluor Drilling Services Inc Flotation and access apparatus for sub-sea drilling structures
US4398487A (en) * 1981-06-26 1983-08-16 Exxon Production Research Co. Fairing for elongated elements
US4474129A (en) * 1982-04-29 1984-10-02 W. R. Grace & Co. Riser pipe fairing
WO1995027101A1 (fr) * 1994-04-04 1995-10-12 Shell Internationale Research Maatschappij B.V. Suppression des vibrations induites par un tourbillon

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3717113A (en) * 1970-10-19 1973-02-20 Fluor Drilling Services Inc Flotation and access apparatus for sub-sea drilling structures
US4398487A (en) * 1981-06-26 1983-08-16 Exxon Production Research Co. Fairing for elongated elements
US4474129A (en) * 1982-04-29 1984-10-02 W. R. Grace & Co. Riser pipe fairing
WO1995027101A1 (fr) * 1994-04-04 1995-10-12 Shell Internationale Research Maatschappij B.V. Suppression des vibrations induites par un tourbillon

Cited By (42)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2378493A (en) * 1998-03-07 2003-02-12 Crp Group Ltd Cladding comprising semi-tubular sections with projections
GB2378493B (en) * 1998-03-07 2003-04-09 Crp Group Ltd Protection of underwater elongate members
GB2363363A (en) * 1999-04-08 2001-12-19 Shell Int Research System for reducing vortex induced vibration of a marine element
WO2000061433A1 (fr) * 1999-04-08 2000-10-19 Shell Internationale Research Maatschappij B.V. Systeme de reduction de vibration induite par effet vortex sur un element naval
GB2363363B (en) * 1999-04-08 2002-07-17 Shell Int Research System for reducing vortex induced vibration of a marine element
US6712559B2 (en) 2000-01-24 2004-03-30 Saipem Sa Seafloor-surface linking device comprising a stabilizing element
FR2804162A1 (fr) * 2000-01-24 2001-07-27 Bouygues Offshore Dispositif de liaison fond-surface comportant un dispositif stabilisateur
WO2001053651A1 (fr) * 2000-01-24 2001-07-26 Bouygues Offshore Dispositif de liaison fond-surface comportant un dispositif stabilisateur
GB2362444B (en) * 2000-04-10 2004-05-19 Crp Group Ltd Protection of underwater elongate members
GB2362444A (en) * 2000-04-10 2001-11-21 Crp Group Ltd Protection of underwater elongate members
WO2002016727A3 (fr) * 2000-08-21 2002-12-12 Cso Aker Maritime Inc Systeme, dispositif et procede de flottabilite de materiel façonne
US6848863B2 (en) 2000-08-21 2005-02-01 Cso Aker Maritime, Inc. Engineered material buoyancy system and device
US7097387B2 (en) 2000-08-21 2006-08-29 Technip France Engineered material buoyancy system and device
GB2385648B (en) * 2000-08-30 2003-12-03 Crp Group Ltd Protection of underwater elongate members
GB2385648A (en) * 2000-08-30 2003-08-27 Crp Group Ltd Protection of underwater elongate members
WO2002018709A1 (fr) * 2000-08-30 2002-03-07 Crp Group Limited Protection d'elements allonges immerges
NL1021347C2 (nl) * 2002-08-28 2004-03-02 Lankhorst Special Mouldings B Suppressie-element voor wervelvibraties, bouwpakket, suppressiestelsel, inrichting voor het winnen van delfstoffen en een matrijs.
WO2004020777A1 (fr) 2002-08-28 2004-03-11 Lankhorst Special Mouldings B.V. Element de suppression des vibrations induites par les tourbillons, kit de construction, appareil d'extraction de matieres minerales et moule
US7458752B2 (en) 2002-08-28 2008-12-02 Lankhorst Special Mouldings B.V. Suppression element for vortex-induced vibrations
GB2441534B (en) * 2007-01-17 2009-01-28 Trelleborg Crp Ltd Supression of vortex induced vibration
GB2441534A (en) * 2007-01-17 2008-03-12 Trelleborg Crp Ltd De-correlation rings for vortex induced vibration suppression
US8500367B2 (en) 2007-01-17 2013-08-06 Trelleborg Crp Limited Suppression of vortex induced vibration
WO2009109776A3 (fr) * 2008-03-03 2009-12-03 Trelleborg Crp Limited Moule pour former une gaine sur un élément allongé
WO2010048080A1 (fr) * 2008-10-23 2010-04-29 Shell Oil Company Systèmes et procédés de réduction des vibrations induites par vortex
WO2010126971A3 (fr) * 2009-05-01 2011-02-24 Shell Oil Company Systèmes et procédés pour réduire des vibrations induites par vortex
EP2438311A4 (fr) * 2009-06-04 2017-08-16 Diamond Offshore Company Module de flottaison pour colonne montante à virures antivibratoires
US9845644B2 (en) 2009-06-04 2017-12-19 Diamond Offshore Company Riser floatation with anti-vibration strakes
CN102313638A (zh) * 2011-08-15 2012-01-11 上海交通大学 均匀流下的深海立管分段模型双向强迫振动实验装置
CN102980732A (zh) * 2012-11-06 2013-03-20 上海交通大学 模拟均匀流下深海立管横向自激振动的试验装置
CN102967431A (zh) * 2012-11-06 2013-03-13 上海交通大学 模拟均匀流下深海立管双向自激振动的试验装置
CN102967431B (zh) * 2012-11-06 2016-04-13 上海交通大学 模拟均匀流下深海立管双向自激振动的试验装置
CN104406753A (zh) * 2014-11-25 2015-03-11 上海交通大学 垂直强迫振荡下的深海细长立管的动力响应测试装置
CN104406754A (zh) * 2014-11-25 2015-03-11 上海交通大学 双向强迫振荡状态下的深海细长立管的动力响应测试装置
CN104458172B (zh) * 2014-11-25 2017-06-13 上海交通大学 一种均匀流下测量细长立管动力响应测试装置
CN104458174A (zh) * 2014-11-28 2015-03-25 上海交通大学 一种面外均匀流下测量细长立管动力响应装置
CN104458174B (zh) * 2014-11-28 2017-06-13 上海交通大学 一种面外均匀流下测量细长立管动力响应装置
CN104502043A (zh) * 2014-12-02 2015-04-08 上海交通大学 模拟海底管土与水平强迫振荡测量细长立管动力响应装置
CN104483083B (zh) * 2014-12-05 2017-06-13 上海交通大学 模拟海底管土与剪切流的深海细长立管动力响应测试装置
CN104483083A (zh) * 2014-12-05 2015-04-01 上海交通大学 模拟海底管土与剪切流的深海细长立管动力响应测试装置
US10107048B2 (en) * 2016-09-29 2018-10-23 Ensco International Incorporated Weathervaning riser joint
US10513888B2 (en) 2016-09-29 2019-12-24 Ensco International Incorporated Weathervaning riser joint
CN110541677A (zh) * 2019-08-13 2019-12-06 中国石油大学(华东) 一种抑制涡激振动的装置、海洋立管和方法

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Publication number Publication date
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