US3835656A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for supplying temporary buoyancy to an underwater pipeline
Assignee: Shell USA Inc
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Filing: 1972-09-01
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Granted: 1974-09-17
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Expires: 1992-09-01
Abstract
Abstract Temporary buoyancy is supplied to a submarine pipeline by connecting one or more sections of interconnected thin walled pipe members to a submarine pipeline such that a compressed gas may be supplied to the thin walled members enabling the net weight in water of combined pipes to be controlled to approximately zero. The compressed gas is ultimately replaced by water as a result of manipulations performed at the water surface.
Inventors
- 👤 Dermott D Mc
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 04:51
CPC Classifications
F; F16; F16L; F16L1/00; F16L1/12; F16L1/16; F16L1/163; B; B63; B63C; B63C7/00; B63C7/06; B63C7/10; F16L1/26
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
166 words
Apparatus for supplying temporary buoyancy to an underwater pipeline while joining two sections of said pipeline, said apparatus comprising: at least one additional pipe section installed in end-to-end fluid communication between said two pipe sections; a plurality of selectively floodable and sinkable chamber-like buoyancy members suitably attached to said two pipe sections to be joined and symmetrically arranged on said pipe sections with respect to the middle of said additional side of pipe section; conduit means interconnecting said chamber-like buoyancy members, one end of said conduit means being of a length sufficient to extend to the surface of the water in which the pipeline is positioned; and pressurizing means connected to said conduit means whereby gas pressure may be supplied to said buoyancy members through said conduit means; the lowermost buoyancy member on each side of said additional pipe section having an opening to control the admission of surrounding water, the gas pressure supplied being sufficient to overcome the water pressure at the lowermost buoyancy member.
Claim 2
Dependent Claim
166 words
Apparatus for supplying temporary buoyancy to an underwater pipeline while joining two sections of said pipeline, said apparatus comprising: at least one additional pipe section installed in end-to-end fluid communication between said two pipe sections; a plurality of selectively floodable and sinkable chamber-like buoyancy members suitably attached to said two pipe sections to be joined and symmetrically arranged on said pipe sections with respect to the middle of said additional side of pipe section; conduit means interconnecting said chamber-like buoyancy members, one end of said conduit means being of a length sufficient to extend to the surface of the water in which the pipeline is positioned; and pressurizing means connected to said conduit means whereby gas pressure may be supplied to said buoyancy members through said conduit means; the lowermost buoyancy member on each side of said additional pipe section having an opening to control the admission of surrounding water, the gas pressure supplied being sufficient to overcome the water pressure at the lowermost buoyancy member.
Claim 3
Dependent Claim
38 words
The apparatus of claim 1 wherein said buoyancy member comprises: a thin walled pipe member; and an end plate weldably attached to each end of said thin walled pipe member; said end plate having a tapped hole therethrough.
Claim 4
Dependent Claim
14 words
The apparatus of claim 1 wherein said conduit means is a high pressure hose.
Claim 5
Dependent Claim
13 words
The apparatus of claim 1 wherein said pressurizing means is an air compressor.
Claim 6
Dependent Claim
13 words
The apparatus of claim 1 wherein said pressurizing means is bottled inert gas.
Claim 7
Independent Claim
121 words
A method of joining two sections of an underwater pipeline disposed on the floor of a body of water, said method comprising the steps of: raising a portion of said pipeline to the surface of the body of water; installing an additional section of pipe in said pipeline; attaching a plurality of selectively-floodable chamber-like buoyancy members to each side of the middle of said additional pipe section, said buoyancy members being interconnected by hose means, said hose means extending to the surface of said body of water; and lowering said pipeline, said additional pipe section, and said buoyancy members to the floor of said body of water while maintaining said additional pipe section and said buoyancy members at substantially neutral buoyancy.
Claim 8
Independent Claim
121 words
A method of joining two sections of an underwater pipeline disposed on the floor of a body of water, said method comprising the steps of: raising a portion of said pipeline to the surface of the body of water; installing an additional section of pipe in said pipeline; attaching a plurality of selectively-floodable chamber-like buoyancy members to each side of the middle of said additional pipe section, said buoyancy members being interconnected by hose means, said hose means extending to the surface of said body of water; and lowering said pipeline, said additional pipe section, and said buoyancy members to the floor of said body of water while maintaining said additional pipe section and said buoyancy members at substantially neutral buoyancy.
Claim 9
Dependent Claim
24 words
The method of claim 6 further including the step of: flooding the buoyancy members by opening them to atmospheric pressure at the water surface.
Claim 10
Dependent Claim
46 words
The method of claim 6 further including, prior to the step of lowering said pipeline to the ocean floor, the step of attaching a weight member at the midpoint of said additional pipe section to supply a moment to overcome the twisting resistance of said pipeline.
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) | 1977-09-16 | 1978-03-18 | 1978-09-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-16 | 1982-03-18 | 1982-09-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-16 | 1986-03-18 | 1986-09-17 | $7700.00 | Window Closed / Lapsed |