GB2301800A - Buoyant Platform - Google Patents
Buoyant Platform Download PDFInfo
- Publication number
- GB2301800A GB2301800A GB9611740A GB9611740A GB2301800A GB 2301800 A GB2301800 A GB 2301800A GB 9611740 A GB9611740 A GB 9611740A GB 9611740 A GB9611740 A GB 9611740A GB 2301800 A GB2301800 A GB 2301800A
- Authority
- GB
- United Kingdom
- Prior art keywords
- raft
- hull
- vessel
- floating platform
- pontoons
- 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.)
- Granted
Links
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
- 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
- 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
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING
- B63B77/00—Transporting or installing offshore structures on site using buoyancy forces, e.g. using semi-submersible barges, ballasting the structure or transporting of oil-and-gas platforms
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- 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
- B63B1/04—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving lift mainly from water displacement with single hull
- B63B2001/044—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving lift mainly from water displacement with single hull with a small waterline area compared to total displacement, e.g. of semi-submersible type
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- 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
Abstract
A floating platform comprising in combination a semisubmersible vessel having two or more pontoons 10, buoyant columns 11 upstanding from those pontoons and a deck 12 supported on the columns (the semisubmersible vessel being of a kind known per se); and a raft 21 comprising a hull 22 having a planform greater than the planform of the vessel and two or more buoyant caissons 23 disposed at or near lateral extremities of the raft 21 and configured so that the raft is capable of floating in a stable attitude with the hull of the raft submerged to such a depth that the vessel can float over the hull of the raft with only the buoyant caissons 23 of the raft piercing the water surface, in which the pontoons 10 of the vessel are secured to upper surfaces of the hull 22, Drilling facilities 32 on the vessel can be used to drill and complete wells 24 with surface wellheads which can subsequently be transferred to and connected to raft mounted production equipment 25.
Description
BUOYANT PLATFORM
The invention relates to a buoyant platform. and to a method of assembling such a platform for the development of an offshore oil/gas field.
In particular the invention relates to a buoyant platform formed from an existing semisubmersible vessel secured to an upper surface of a purpose built raft held down against the action of its own buoyancy in the manner of a tension leg platform (TLP). Platforms of this type have been described and claimed in our U.K. Patent Specification No. 2285773A.
Semisubmersible vessels have been used for some years in the offshore industry for the purpose of drilling, production and marine operations. These semisubmersible vessels typically have two parallel spaced apart pontoons with buoyant columns upstanding from those pontoons to support a deck. In transit the vessel is deballasted so that it can float on the pontoons with the columns clear of the water. This allows the vessel to operate as a catamaran. For activities which require a stable offshore platform, the vessel is ballasted down so that the pontoons are submerged, and only the buoyant columns pierce the water surface thus giving the semisubmersible vessel a substantial buoyancy with a small waterplane area.
This configuration - which is illustrated in U.K. Patent Specification 2068439A - provides a more stable platform for offshore operations than would be provided by a conventional ship shaped vessel. However, for severe seastates, even a semisubmersible vessel becomes subject to movements which are unacceptable for many offshore operations, including inter alia drilling and production. These unacceptable movements lead to 'downtime' during which all the costs of operating the semisubmersible vessel are incurred, but no useful work is done.
Development of offshore oil and gas fields in hostile areas (in terms of severe sea states) has led to requirements for drilling, production and marine operations to be carried out in progressively more severe sea states, with minimum downtime.
Thus there is a requirement for a buoyant platform which is capable of continued operation in more severe sea states than can be tolerated by semisubmersible vessels currently in use. This may be combined with a further requirement for oil storage at an open sea site.
In some cases it may be advantageous to employ mobile drilling facilities on a semisubmersible vessel (which is already equipped with power supplies and drilling equipment) to enhance the capabilities of another floating vessel. An example of this enhancement is shown in U.K. Patent Specification 2250767A, in which two floating vessels are located beside each other.
In the present case the semisubmersible vessel is associated with another floating component, herein referred to as a "raft" Deck load and area limitations, which would normally prevent heavy and bulky equipment from being carried, can be overcome by supporting the semisubmersible vessel on the raft.
It may also be desirable to drill oil/gas wells at a certain location, and then leave those wells tied back to surface wellheads at that location, while the drilling equipment is removed and reused at another location.
The invention provides a floating platform comprising in combination a semisubmersible vessel having two or more pontoons, buoyant columns upstanding from those pontoons and a deck supported on the columns (the semisubmersible vessel being of a kind known per se); and a raft comprising a hull having a planform greater than the planform of the vessel and two or more buoyant caissons disposed at or near lateral extremities of the raft and configured so that the raft is capable of floating in a stable attitude with the hull of the raft submerged to such a depth that the vessel can float over the hull of the raft with only the buoyant caissons of the raft piercing the water surface, in which the pontoons of the vessel are secured to upper surfaces of the hull, and drilling facilities on the vessel can be used to drill and complete wells with surface wellheads which can subsequently be transferred to and connected to raft mounted production equipment.
It is preferred that the semisubmersible vessel can subsequently be released from and floated off the raft when drilling is completed.
It is further preferred that the raft has means whereby after the semi submersible vessel has been removed, the raft can be submerged to such a depth that no part of the raft pierces the water surface.
It is further preferred that the raft is adapted to rest on the seabed.
In circumstances in which the semisubmersible can be released, the semisubmersible vessel may later be floated over and reconnected to the hull to retrieve the raft mounted wells and wellheads in order to carry out further drilling or workover activities.
It is preferred that the caissons of the raft have mooring clamps to secure the platform on station.
Mooring equipment for the platform may comprise vertical tensioned tethers.
The platform may incorporate dynamic positioning equipment.
It is preferred that the vertical depth of the hull is less at points on the periphery of the hull than it is at the centre of the hull.
It is also preferred that either or both of the upper and lower surfaces of the hull slope upwardly or downwardly (as the case may be) from the edge of the hull towards the centre of the hull.
Peripheral edges of the hull may be profiled to reduce resistance to wave and/or current loads.
It is preferred that the hull has compartments for the storage of oil, and there is provision for counterflooding to compensate for the accumulation or depletion of oil within the hull.
The invention also provides a method of developing an offshore oilfield which comprises the assembly of a platform as described above including the steps of deballasting a semisubmersible vessel so that it floats on its pontoons, ballasting a raft (of the kind described) so that the upper surface of its hull is submerged to a depth greater than the deballasted draft of the vessel, floating the vessel over the hull of the raft, deballasting the raft so that the pontoons of the vessel are raised above water level, and then securing the pontoons of the vessel to upper surfaces of the hull; using drilling facilities on the vessel to drill and complete wells beneath the platform with surface wellheads; and then transferring the surface wellheads to the raft for connection to raft mounted production equipment.
It is preferred that the semisubmersible vessel is subsequently released from and floated off the raft when drilling is completed.
It is further preferred that the semisubmersible vessel is floated over and reconnected to the hull to retrieve the raft mounted wells and wellheads, and further drilling or workover activities are carried out.
A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which:
Figure 1 is a side view of a buoyant platform;
Figure 2 is an end view of that platform;
As shown in Figure 1, a floating platform includes a generally conventional semisubmersible drilling vessel, which is frequently referred to in the offshore industry as a
Mobile Offshore Drilling Unit or MODU. This MODU has two elongated pontoons 10, four buoyant columns 11 (upstanding from the ends of each of those pontoons), and a deck 12 supported on the columns. The pontoons 10 are subdivided internally into selectively ballastable watertight compartments. The MODU has anchor chain lockers within its corner columns, and there are winches (not shown) on the tops of those columns and fairleaders 15 near the bases of those columns for deploying mooring arrays.
The MODU illustrated by way of example is in fact a SEDCO 600 series semisubmersible drilling vessel, of which three were located worldwide in various operating roles at the time of making this application. This MODU is configured for end bay drilling.
Following the invention, the MODU is releasably secured to a purpose built raft 21. The raft has a generally flat hull 22 with a planform larger than the planform of the MODU. The hull 22 has three caissons 23 (located at two adjacent corners and midway along its opposite side), and these caissons stand slightly higher above the upper surface of the hull 22 than the vertical draft of the pontoons 10 of the MODU in their deballasted condition. A raft having a generally flat hull and at least two upstanding caissons at or near its lateral extremities will be referred to as a raft of the kind described.
In the simplest form of the invention, the MODU is secured to the upper surface of the hull 22 between the caissons 23. In this way the raft 21 gives additional buoyancy to the MODU, and also improves the stability characteristics of the MODU. Fixing the MODU to the raft 21 reduces the wave loads applied to the MODU, because these loads are reacted largely by the raft. Thus fatigue lives in structural elements of the MODU will be significantly improved.
The raft 21 may have internal compartments for ballast water and the storage of oil.
These compartments are not shown in detail in the Figures, but if the raft were to be made of steel, these would be constructed like conventional compartments of an ocean going VLCC (Very Large Crude Carrier). If the raft were to be made of concrete, the compartments would be formed like cells in a conventional concrete structure.
The raft is fitted with pipework and one or two pump rooms as required for ballast and oil transfer operations. The raft pump rooms are typically located directly below the pump rooms in the MODU pontoons with watertight access from these pontoons. Electrical feeders and pipework to the raft pump rooms can therefore easily be run via the normal routes up through the columns of the MODU.
To compensate for changes in buoyancy in a steel raft, counter flooding arrangements would be necessary, so that sea water could replace or be replaced by oil as the compartments were emptied or filled. Advantageously a flexible compartment liner could physically separate the oil and the sea water to be used as ballast. Because of the large mass of a concrete raft, it is unlikely that counterflooding would be necessary. However, if dry oil storage was adopted, it might be necessary to fill the tops of the storage compartments with an inert gas.
The raft 21 has a moonpool through which drill strings 24 and subsequently rigid or flexible riser systems 25 can be run to the seabed, as shown particularly in Figure 1. The drill strings 24 are deployed from a drilling derrick 32 on the deck 12 of the MODU. The drilling equipment (power supplies, mud tank etc.) is mounted on the MODU, and only minimal facilities are mounted on the caissons 23 of the raft 21. In this case the raft will be required to remain on location over a drilling template or production manifold 26, which is secured to the seabed. Following the invention, when the wells and wellheads are completed, they can be transferred (under tension) from the deck of the MODU to a caisson 23 of the raft 21.
In a preferred method of keeping the platform on location, the raft 21 is held down against the action of its own buoyancy in the manner of a Tension Leg Platform or TLP. In this case tethers 28 extend down from tensioning devices 29 beneath the caissons 23 to foundation templates 31 on the seabed. Conventional mooring lines 20 are deployed from the winches of the MODU and through fairleaders 15 to anchors on the seabed. The mooring lines 20 are set out to a conventional eight anchor mooring array (seen best in Figure 2). The mooring lines 20 can be used to position the combined floating platform (i.e. MODU plus raft) over the required drilling location prior to commencement of drilling operations.
An important feature of the invention relates to an alternative mooring arrangement. The fairleaders shown in Figure 1 can be repositioned on the caissons 23, and can be arranged to clamp the mooring lines 20, so that the mooring loads are carried in the raft 21 rather than in the MODU itself. In use the winches (not shown) are used to adjust the mooring lines 20, which are then clamped in the fairleaders 15 on the caissons.
In a variation of the basic configuration of the raft, the hull 22 may be slightly dome shaped so that its draft at its centre is less than its draft around its periphery. With a dome shaped raft, the platform will ride the waves better, and so in theory a smaller air gap would be required between the nominal sea level and the lowest elements of the deck.
Turning now to the construction and assembly of the platform, many MODU's already exist which could be used as the upper part of the platform. The purpose built raft 21 is of simple construction, and could be built in sections in conventional shipyards and then assembled in sheltered water. Alternatively, the raft could be formed of concrete. Using conventional shipbuilding or concrete pouring techniques, the raft (with internal compartments for the storage of oil) could be constructed and assembled very economically.
To assemble the complete platform, the raft 21 would be ballasted down so that only the tops of the caissons 23 were above sea level. The MODU would be de-ballasted so that it floated only on its pontoons 10, and would then be positioned over the raft 21. The raft 21 would be deballasted so that the upper surface of its hull 22 was above sea level and the
MODU was clear of the water. In this condition the pontoons of the MODU could be secured to the upper surface of the hull.
When drilling operations are completed, and the drilling derrick 32 and associated drilling equipment are no longer required at that particular location, the MODU would be released from the raft 21, and floated off to another location.
When the MODU has been released, the raft could be drawn down towards the seabed by selective ballasting and/or adjustment of its moorings. The raft would be totally submerged to a depth no deeper than that at which diver intervention on the wellheads is possible. The raft could either be secured at a mid water depth position, or could rest on the seabed if the depth of the sea at that point was shallow. This feature would be of value at locations which are threatened in winter months by drifting ice. The MODU could later return for further drilling or work over operations (e.g. during the following summer).
In one form of the invention, the raft - once in position on site - could be permanently located below the water surface.
The invention has the advantage that a single MODU can be used at several locations where surface or near surface wellheads are required. The sophisticated mechanical equipment on the MODU could be used sequentially in combination with several low cost rafts.
The raft(s) provide extra buoyancy and greater stability to the MODU while drilling is in progress, so that drilling can continue in more severe sea states than would otherwise be possible.
Claims (19)
1. A floating platform comprising in combination a semisubmersible vessel having two or
more pontoons, buoyant columns upstanding from those pontoons and a deck supported
on the columns (the semisubmersible vessel being of a kind known per se); and a raft
comprising a hull having a planform greater than the planform of the vessel and two or
more buoyant caissons disposed at or near lateral extremities of the raft and configured
so that the raft is capable of floating in a stable attitude with the hull of the raft submerged
to such a depth that the vessel can float over the hull of the raft with only the buoyant
caissons of the raft piercing the water surface, in which the pontoons of the vessel are
secured to upper surfaces of the hull, and drilling facilities on the vessel can be used to
drill and complete wells with surface wellheads which can subsequently be transferred to
and connected to raft mounted production equipment.
2. A floating platform as claimed in Claim 1 in which the semisubmersible vessel can
subsequently be released from and floated off the raft when drilling is completed.
3. A floating platform as claimed in Claim 2, in which the raft has means whereby after the
semisubmersible vessel has been removed, the raft can be submerged to such a depth
that no part of the raft pierces the water surface.
4. A floating platform as claimed in Claim 3, in which the raft is adapted to rest on the
seabed.
5. A floating platform as claimed in any one of Claims 2 to 4 in which the semisubmersible
vessel can be floated over and reconnected to the hull to retrieve the raft mounted wells
and wellheads in order to carry out further drilling or workover activities.
6. A floating platform as claimed in any one of the preceding claims in which the caissons of
the raft have mooring clamps to secure the platform on station.
7. A floating platform as claimed in any one of the preceding claims in which mooring
equipment comprises vertical tensioned tethers.
8. A floating platform as claimed in any one of the preceding claims in which the platform
incorporates dynamic positioning equipment.
9. A floating platform as claimed in any one of the preceding claims in which the vertical
depth of the hull is less at points on the periphery of the hull than it is at the centre of the
hull.
10. A floating platform as claimed in any one of the preceding claims in which either or both of
the upper and lower surfaces of the hull slope upwardly or downwardly (as the case may
be) from the edge of the hull towards the centre of the hull.
11. A floating platform as claimed in any one of the preceding claims in which peripheral
edges of the hull are profiled to reduce resistance to wave and/or current loads.
12. A floating platform as claimed in any one of the preceding claims in which the hull has
compartments for the storage of oil, and there is provision for counterflooding to
compensate for the accumulation or depletion of oil within the hull.
13. A floating platform substantially as hereinbefore described with reference to and as
shown in the accompanying drawings.
14. A method of developing an offshore oilfield which comprises the assembly of a platform
as claimed in any one of the preceding claims including the steps of deballasting a
semi submersible vessel so that it floats on its pontoons, ballasting a raft (of the kind
described) so that the upper surface of its hull is submerged to a depth greater than the
deballasted draft of the vessel, floating the vessel over the hull of the raft, deballasting the
raft so that the pontoons of the vessel are raised above water level, and then securing the
pontoons of the vessel to upper surfaces of the hull; using drilling facilities on the vessel
to drill and complete wells beneath the platform with surface wellheads; and then
transferring the surface weliheads to the raft for connection to raft mounted production
equipment.
15. A method as claimed in Claim 14 in which the semisubmersible vessel is subsequently
released from and floated off the raft when drilling is completed.
16. A method as claimed in Claim 15 in which the semisubmersible vessel is floated over and
reconnected to the hull to retrieve the raft mounted wells and wellheads, and further
drilling or workover activities are carried out.
17. A method substantially as hereinbefore described with reference to the accompanying
drawings.
Amendments to the claims have been filed as follows 1. A floating platform comprising in combination a semisubmersible vessel having two or
more pontoons, buoyant columns upstanding from those pontoons and a deck supported
on the columns (the semisubmersible vessel being of a kind known per se); and a raft
comprising a hull having a planform greater than the planform of the vessel configured so
that the raft is capable of floating in a stable attitude with the hull of the raft submerged to
such a depth that the vessel can float over the hull of the raft, in which the pontoons of
the vessel are secured to upper surfaces of the hull, drilling facilities on the vessel are
adapted to drill and complete wells with surface wellheads, and the platform has means to
transfer and connect the surface wellheads to raft mounted production equipment.
2. A floating platform as claimed in Claim 1 in which means securing the pontoons of the
semisubmersible vessel to the raft can subsequently be released, so that the vessel can
be floated off the raft when drilling is completed.
3. A floating platform as claimed in Claim 2, in which the raft has means whereby after the
semisubmersible vessel has been removed, the raft can be submerged to such a depth
that no part of the raft pierces the water surface.
4. A floating platform as claimed in Claim 3, in which the raft is adapted to rest on the
seabed.
5. A floating platform as claimed in any one of Claims 2 to 4 in which the semisubmersible
vessel can be floated over and reconnected to the hull to retrieve the raft mounted wells
and wellheads in order to carry out further drilling or workover activities.
6. A floating platform as claimed in any one of the preceding claims in which the raft has
mooring clamps to secure the platform on station 7. A floating platform as claimed in any one of the preceding claims in which mooring
equipment comprises vertical tensioned tethers.
8. A floating platform as claimed in any one of the preceding claims in which the platform
incorporates dynamic positioning equipment.
9. A floating platform as claimed in any one of the preceding claims in which the vertical
depth of the hull is less at points on the periphery of the hull than it is at the centre of the
hull.
10. A floating platform as claimed in any one of the preceding claims in which either or both of
the upper and lower surfaces of the hull slope upwardly or downwardly (as the case may
be) from the edge of the hull towards the centre of the hull.
11. A floating platform as claimed in any one of the preceding claims in which peripheral
edges of the hull are profiled to reduce resistance to wave and/or current loads.
12. A floating platform as claimed in any one of the preceding claims in which the hull has
compartments for the storage of oil, and there is provision for counterflooding to
compensate for the accumulation or depletion of oil within the hull.
13. A floating platform comprising in combination a semisubmersible vessel having two or
more pontoons, buoyant columns upstanding from those pontoons and a deck supported
on the columns (the semisubmersible vessel being of a kind known per se); and a raft
comprising a hull having a planform greater than the planform of the vessel configured so
that the raft is capable of floating in a stable attitude with the hull of the raft submerged to
such a depth that the vessel can float over the hull of the raft, in which the pontoons of
the vessel are secured to upper surfaces of the hull, and drilling facilities on the vessel
can be used to drill and complete wells with surface wellheads which can subsequently be
transferred to and connected to raft mounted production equipment, and in which the se,riisubmersible vessel can subsequently be released from and floated off the raft when
drilling is completed.
14. A floating platform as claimed in any one of the preceeding claims in which the raft has
two or more buoyant caissons disposed at or near lateral extremities of the raft.
15. A floating platform substantially as hereinbefore described with reference to and as
shown in the accompanying drawings.
16. A method of developing an offshore oilfield which comprises the assembly of a platform
as claimed in any one of the preceding claims including the steps of deballasting a
semisubmersible vessel so that it floats on its pontoons, ballasting a raft so that the upper
surface of its hull is submerged to a depth greater than the deballasted draft of the
vessel, floating the vessel over the hull of the raft, deballasting the raft so that the
pontoons of the vessel are raised above water level, and then securing the pontoons of
the vessel to upper surfaces of the hull; using drilling facilities on the vessel to drill and
complete wells beneath the platform with surface wellheads; and then transferring the
surface wellheads to the raft for connection to raft mounted production equipment.
17. A method as claimed in Claim 15 in which the semisubmersible vessel is subsequently
released from and floated off the raft when drilling is completed.
18. A method as claimed in Claim 16 in which the semisubmersible vessel is floated over and
reconnected to the hull to retrieve the raft mounted wells and wellheads, and further
drilling or workover activities are carried out.
19. A method substantially as hereinbefore described with reference to the accompanying
drawings.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GBGB9511541.6A GB9511541D0 (en) | 1995-06-07 | 1995-06-07 | Buoyant Platform |
Publications (3)
Publication Number | Publication Date |
---|---|
GB9611740D0 GB9611740D0 (en) | 1996-08-07 |
GB2301800A true GB2301800A (en) | 1996-12-18 |
GB2301800B GB2301800B (en) | 1999-03-24 |
Family
ID=10775681
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GBGB9511541.6A Pending GB9511541D0 (en) | 1995-06-07 | 1995-06-07 | Buoyant Platform |
GB9611740A Expired - Fee Related GB2301800B (en) | 1995-06-07 | 1996-06-05 | Buoyant platform |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GBGB9511541.6A Pending GB9511541D0 (en) | 1995-06-07 | 1995-06-07 | Buoyant Platform |
Country Status (4)
Country | Link |
---|---|
AU (1) | AU5905596A (en) |
GB (2) | GB9511541D0 (en) |
MY (1) | MY132193A (en) |
WO (1) | WO1996040549A1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2000027692A1 (en) * | 1998-10-26 | 2000-05-18 | Lund, Mohr & Giæver-Enger Marin As | Device for positioning of vessels |
WO2000073135A1 (en) * | 1999-05-27 | 2000-12-07 | Aktieselskabet Dampskibsselskabet Svendborg | A method of establishing and/or operating a bore well in a seabed and a drilling vessel for use in connection therewith |
ES2203265A1 (en) * | 1998-06-05 | 2004-04-01 | Navion As | Floating structure |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
RU2422614C2 (en) | 2006-03-30 | 2011-06-27 | Эксонмобил Апстрим Рисерч Компани | Mobile arctic drilling system of year-round operation |
RU2475407C1 (en) * | 2011-11-10 | 2013-02-20 | Российская Федерация, от имени которой выступает государственный заказчик Министерство промышленности и торговли Российской Федерации (Минпромторг России) | Marine semisubmersible helideck |
GB2538275B (en) | 2015-05-13 | 2018-01-31 | Crondall Energy Consultants Ltd | Floating production unit and method of installing a floating production unit |
CN113879472B (en) * | 2021-11-03 | 2024-01-30 | 江苏科技大学 | Semi-submersible drilling platform system with pose compensation capability and control method |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4167148A (en) * | 1976-09-13 | 1979-09-11 | Fayren Jose M | Floating apparatus and method of assembling the same |
GB2207892A (en) * | 1987-08-12 | 1989-02-15 | Goetaverken Arendal Ab | A reinforcement element for offshore work vessels |
GB2285773A (en) * | 1994-01-21 | 1995-07-26 | Kvaerner Earl & Wright | Floating platform with buoyant raft |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NZ240667A (en) * | 1990-12-10 | 1993-06-25 | Shell Int Research | Offshore oil drilling from drilling vessel in support of a compliant platform |
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1995
- 1995-06-07 GB GBGB9511541.6A patent/GB9511541D0/en active Pending
-
1996
- 1996-06-05 WO PCT/GB1996/001323 patent/WO1996040549A1/en active Application Filing
- 1996-06-05 GB GB9611740A patent/GB2301800B/en not_active Expired - Fee Related
- 1996-06-05 AU AU59055/96A patent/AU5905596A/en not_active Abandoned
- 1996-06-06 MY MYPI96002274A patent/MY132193A/en unknown
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4167148A (en) * | 1976-09-13 | 1979-09-11 | Fayren Jose M | Floating apparatus and method of assembling the same |
GB2207892A (en) * | 1987-08-12 | 1989-02-15 | Goetaverken Arendal Ab | A reinforcement element for offshore work vessels |
GB2285773A (en) * | 1994-01-21 | 1995-07-26 | Kvaerner Earl & Wright | Floating platform with buoyant raft |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
ES2203265A1 (en) * | 1998-06-05 | 2004-04-01 | Navion As | Floating structure |
ES2203265B1 (en) * | 1998-06-05 | 2005-06-01 | Navion As | FLOATING STRUCTURE. |
WO2000027692A1 (en) * | 1998-10-26 | 2000-05-18 | Lund, Mohr & Giæver-Enger Marin As | Device for positioning of vessels |
WO2000073135A1 (en) * | 1999-05-27 | 2000-12-07 | Aktieselskabet Dampskibsselskabet Svendborg | A method of establishing and/or operating a bore well in a seabed and a drilling vessel for use in connection therewith |
US6682265B1 (en) | 1999-05-27 | 2004-01-27 | A.P. Moller-Maersk A/S | Method of establishing and/or operating a bore well in a seabed and a drilling vessel for use in connection therewith |
Also Published As
Publication number | Publication date |
---|---|
GB9511541D0 (en) | 1995-08-02 |
GB2301800B (en) | 1999-03-24 |
WO1996040549A1 (en) | 1996-12-19 |
MY132193A (en) | 2007-09-28 |
AU5905596A (en) | 1996-12-30 |
GB9611740D0 (en) | 1996-08-07 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
732E | Amendments to the register in respect of changes of name or changes affecting rights (sect. 32/1977) | ||
PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 20000605 |