US3798915A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Offshore apparatus and installation technique
Assignee: ExxonMobil Upstream Research Co
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Filing: 1972-03-06
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Granted: 1974-03-26
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Expires: 1992-03-06
Abstract
Abstract Method and apparatus are disclosed for imparting stability to a storage vessel or similar structure as it is moved vertically between the surface and floor of a body of water. The method comprises disposing a quantity of a lighter-than-water fluid within the structure in an orientation about its center of gravity such that whenever the structure is situated at or beneath the water surface and is displaced from a vertical orientation, the fluid will generate a righting moment which tends to restore the structure to its original position. The fluid disposed within the structure is constrained against migration and the structure may then, for example, be lowered towards the floor of the body of water. The method is particularly applicable to the underwater installation of storage vessels of the type having at least three separate storage chambers and provided with means for regulating the quantity of fluid in each of the chambers without permitting migration between storage chambers.
Inventors
- 👤 J Burkhardt
- 👤 J Ortloff
- 👤 W Loth
- 👤 R Hickox
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 00:32
CPC Classifications
B; B65; B65D; B65D88/00; B65D88/78
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
157 words
In a method of installing a structure on the floor of a body of water, the method of moving the structure between the surface of said body of water and the floor thereof comprising: a. disposing a quantity of a lighter-than-water, incompressible fluid within the structure, in an orientation about the center of gravity of the structure such that whenever the structure is totally immersed and is tilted from a vertical orientation, the fluid will generate a righting moment tending to restore the structure to the vertical orientation; b. constraining said fluid against lateral migration within said structure while permitting pressure communication between said fluid and the water situated therebelow; c. adjusting the quantity of said lighter-than-water fluid within said structure without permitting lateral migration thereof as required to render said structure no more than neutrally buoyant when immersed; and d. moving said structure vertically between the surface of said body of water and the floor thereof.
Claim 2
Dependent Claim
157 words
In a method of installing a structure on the floor of a body of water, the method of moving the structure between the surface of said body of water and the floor thereof comprising: a. disposing a quantity of a lighter-than-water, incompressible fluid within the structure, in an orientation about the center of gravity of the structure such that whenever the structure is totally immersed and is tilted from a vertical orientation, the fluid will generate a righting moment tending to restore the structure to the vertical orientation; b. constraining said fluid against lateral migration within said structure while permitting pressure communication between said fluid and the water situated therebelow; c. adjusting the quantity of said lighter-than-water fluid within said structure without permitting lateral migration thereof as required to render said structure no more than neutrally buoyant when immersed; and d. moving said structure vertically between the surface of said body of water and the floor thereof.
Claim 3
Dependent Claim
28 words
The method of claim 1 wherein said structure is a storage vessel and said fluid is constrained against migration by a plurality of partitions disposed within said vessel.
Claim 4
Dependent Claim
12 words
A method of claim 2 wherein said incompressible fluid is a liquid.
Claim 5
Dependent Claim
11 words
The method of claim 3 wherein said liquid is an oil.
Claim 6
Dependent Claim
13 words
The method of claim 2 wherein said incompressible fluid includes a solid material.
Claim 7
Dependent Claim
93 words
In a method of moving a storage tank between the surface of a body of water and the floor thereof, wherein said tank is a cylindrical vessel having a top and a plurality of circular and radial partitions dividing the same into a plurality of laterally separate compartments, the improvement comprising disposing a quantity of a lighter-than-water fluid within said tank in laterally separate compartments oriented about the center of gravity such that when the tank is totally immersed and is tilted from a vertical orientation, the fluid will generate a righting moment.
Claim 8
Dependent Claim
93 words
In a method of moving a storage tank between the surface of a body of water and the floor thereof, wherein said tank is a cylindrical vessel having a top and a plurality of circular and radial partitions dividing the same into a plurality of laterally separate compartments, the improvement comprising disposing a quantity of a lighter-than-water fluid within said tank in laterally separate compartments oriented about the center of gravity such that when the tank is totally immersed and is tilted from a vertical orientation, the fluid will generate a righting moment.
Claim 9
Dependent Claim
12 words
The method of claim 6 wherein said lighter-than-water fluid is substantially incompressible.
Claim 10
Dependent Claim
12 words
The method of claim 7 wherein said incompressible fluid is an oil.
Claim 11
Dependent Claim
13 words
The method of claim 7 wherein said incompressible fluid includes a solid material.
Claim 12
Independent Claim
154 words
A method of transferring a storage vessel situated at the surface of a body of water to the floor thereof, comprising: a. disposing a lighter-than-water fluid within said vessel in a quantity sufficient to impart a positive buoyancy to said vessel and constrained therewithin in at least three laterally separate bodies in an orientation about the center of gravity of the vessel such that said constrained bodies of said fluid will generate a righting moment when the vessel is tilted from a vertical orientation; b. attaching a flexible lowering means to said storage vessel; c. withdrawing quantities of fluid from said bodies of fluid until said vessel is no more than neutrally buoyant and the center of gravity of said vessel is situated below the center of buoyancy thereof; and d. lowering said vessel to the floor of said body of water with said flexible lowering means while supporting same from the water surface.
Claim 13
Independent Claim
154 words
A method of transferring a storage vessel situated at the surface of a body of water to the floor thereof, comprising: a. disposing a lighter-than-water fluid within said vessel in a quantity sufficient to impart a positive buoyancy to said vessel and constrained therewithin in at least three laterally separate bodies in an orientation about the center of gravity of the vessel such that said constrained bodies of said fluid will generate a righting moment when the vessel is tilted from a vertical orientation; b. attaching a flexible lowering means to said storage vessel; c. withdrawing quantities of fluid from said bodies of fluid until said vessel is no more than neutrally buoyant and the center of gravity of said vessel is situated below the center of buoyancy thereof; and d. lowering said vessel to the floor of said body of water with said flexible lowering means while supporting same from the water surface.
Claim 14
Dependent Claim
11 words
The method of claim 10 wherein said fluid is substantially incompressible.
Claim 15
Dependent Claim
12 words
The method of claim 11 wherein said incompressible fluid is an oil.
Claim 16
Dependent Claim
13 words
The method of claim 11 wherein said incompressible fluid includes a solid material.
Claim 17
Dependent Claim
28 words
The method of claim 10 including the step of regulating the quantity of said fluid within said vessel to control the buoyancy of said vessel during its descent.
Claim 18
Independent Claim
255 words
A method of installing a storage vessel on the floor of a body of water comprising: a. disposing a lighter-than-water compressible fluid within said vessel in a quantity sufficient to impart a positive buoyancy to said vessel in at least three laterally separate bodies, arranged symmetrically abouT a vertical axis through the center of gravity of said vessel, each said body containing a substantially equal volume of said compressible fluid; b. constraining the compressible fluid contained in said bodies against movement in relation to said vessel when said vessel is tilted from a vertical orientation; c. floating said vessel containing said compressible fluid constrained therein to an offshore installation site; d. disposing a substantially incompressible, lighter-than-water fluid within said vessel in at least three laterally separate bodies arranged symmetrically about a vertical axis through the center of gravity of said vessel each said body containing a substantially equal volume of said incompressible fluid; e. attaching a flexible lowering means to said storage vessel; f. withdrawing quantities of said compressible fluid from said vessel until said vessel contains only said incompressible fluid, is no more than neutrally buoyant, and has its center of buoyancy situated above its center of gravity; g. lowering said vessel to bottom with said flexible lowering means while simultaneously constraining said bodies of incompressible fluid against movement in relation to said vessel when said vessel is tilted from its vertical orientation; and thereafter, h. withdrawing additional quantities of said incompressible fluid from said vessel with said vessel situated on said submerged bottom.
Claim 19
Independent Claim
255 words
A method of installing a storage vessel on the floor of a body of water comprising: a. disposing a lighter-than-water compressible fluid within said vessel in a quantity sufficient to impart a positive buoyancy to said vessel in at least three laterally separate bodies, arranged symmetrically abouT a vertical axis through the center of gravity of said vessel, each said body containing a substantially equal volume of said compressible fluid; b. constraining the compressible fluid contained in said bodies against movement in relation to said vessel when said vessel is tilted from a vertical orientation; c. floating said vessel containing said compressible fluid constrained therein to an offshore installation site; d. disposing a substantially incompressible, lighter-than-water fluid within said vessel in at least three laterally separate bodies arranged symmetrically about a vertical axis through the center of gravity of said vessel each said body containing a substantially equal volume of said incompressible fluid; e. attaching a flexible lowering means to said storage vessel; f. withdrawing quantities of said compressible fluid from said vessel until said vessel contains only said incompressible fluid, is no more than neutrally buoyant, and has its center of buoyancy situated above its center of gravity; g. lowering said vessel to bottom with said flexible lowering means while simultaneously constraining said bodies of incompressible fluid against movement in relation to said vessel when said vessel is tilted from its vertical orientation; and thereafter, h. withdrawing additional quantities of said incompressible fluid from said vessel with said vessel situated on said submerged bottom.
Claim 20
Dependent Claim
18 words
The method of claim 15 wherein said compressible fluid is air and said incompressible fluid is an oil.
Claim 21
Dependent Claim
74 words
Apparatus comprising: a. a cylindrical storage vessel having an open bottom and a closed top; b. a plurality of radial and circular vertical partitions situated in said vessel that divide the vessel into a plurality of separate, radially subdivided, concentric storage chambers, said partitions preventing fluid communication therethrough; and c. means for regulating the quantity of a buoyant fluid in each of said storage chambers without permitting migration of said fluid between storage chambers.
Claim 22
Dependent Claim
74 words
Apparatus comprising: a. a cylindrical storage vessel having an open bottom and a closed top; b. a plurality of radial and circular vertical partitions situated in said vessel that divide the vessel into a plurality of separate, radially subdivided, concentric storage chambers, said partitions preventing fluid communication therethrough; and c. means for regulating the quantity of a buoyant fluid in each of said storage chambers without permitting migration of said fluid between storage chambers.
Claim 23
Dependent Claim
18 words
The apparatus defined by claim 17 wherein said vessel includes a plurality of vertical pile guides extending therethrough.
Claim 24
Dependent Claim
110 words
Apparatus comprising: a. a circular cylindrical vessel having a closed top; b. a plurality of circular partitions disposed within said vessel and depending vertically from the top thereof; c. a plurality of radial partitions depending vertically from the top of said vessel and extending between said circular partitions to divide said tank into a plurality of laterally separate storage chambers; d. valve means positioned on each of said storage chambers to control the introduction and withdrawal of fluid therefrom; and e. manifold means mounted on said vessel for permitting introduction and withdrawal of fluid from each chamber from a single conduit while preventing migration of fluid between said storage chambers.
Claim 25
Dependent Claim
110 words
Apparatus comprising: a. a circular cylindrical vessel having a closed top; b. a plurality of circular partitions disposed within said vessel and depending vertically from the top thereof; c. a plurality of radial partitions depending vertically from the top of said vessel and extending between said circular partitions to divide said tank into a plurality of laterally separate storage chambers; d. valve means positioned on each of said storage chambers to control the introduction and withdrawal of fluid therefrom; and e. manifold means mounted on said vessel for permitting introduction and withdrawal of fluid from each chamber from a single conduit while preventing migration of fluid between said storage chambers.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-25 | 1977-09-24 | 1978-03-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-25 | 1981-09-24 | 1982-03-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-25 | 1985-09-24 | 1986-03-26 | $7700.00 | Window Closed / Lapsed |