Patent US3988898A successfully refreshed from Google Patents.
US3988898A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pipelines and marine platforms
Assignee: INTERCONTINENTAL MARINE DEV Ltd
•
Filing: 1974-12-26
•
Granted: 1976-11-02
•
Expires: 1994-12-26
Abstract
Abstract A marine platform is described incorporating a submerged buoyancy chamber which is anchored to drilled piles in the sea bed by cables. Each anchorage point lies inside a working chamber mounted on the pile to enable workmen inside the chamber to release the coupling between the cable and the pile when the cable needs to be replaced. The buoyancy chamber and the working chamber both have airlocks to enable the transfer of workmen between each chamber and a submersible craft. The buoyancy chamber supports a deck which lies above sea level. The deck is in fluid communication with a wellhead on the sea bed by means of risers. Each riser incorporates two concentric tubes. The inner tube carries oil from the wellhead and the other tube contains a hydraulic fluid through which valves at the wellhead can be controlled from the deck such that the valves close if riser rupture releases hydraulic pressure.
Inventors
- 👤 Ronald D. McDonald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:53
CPC Classifications
B; B63; B63C; B63C11/00; B63C11/34; B63C11/36; B63C11/40; B63B; B63B1/00; B63B1/02; B63B1/10; B63B1/107; B63B21/00; B63B21/50; B63B21/502; B63B35/00; B63B35/44; B63B35/4413; E; E21; E21B; E21B34/00; E21B34/16; E21B43/00; E21B43/01; E21B43/017
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
128 words
A tension leg marine platform comprising a buoyancy chamber, a plurality of anchoring arrangements secured to the sea bed, a plurality of tension legs, each tension leg extending between a corresponding one of the anchoring arrangements and the buoyancy chamber to hold the buoyancy chamber submerged below the level of the sea, a platform, and means supporting the platform on the buoyancy chamber but above the level of the sea, each anchoring arrangement for each leg comprising a pile driven into the sea bed, an air filled working chamber mounted on the pile and defining an orifice through which a said leg can extend into the chamber, and clamping means secured to the chamber and housed within the chamber, the clamping means clamping the leg to the pile.
Claim 2
Dependent Claim
128 words
A tension leg marine platform comprising a buoyancy chamber, a plurality of anchoring arrangements secured to the sea bed, a plurality of tension legs, each tension leg extending between a corresponding one of the anchoring arrangements and the buoyancy chamber to hold the buoyancy chamber submerged below the level of the sea, a platform, and means supporting the platform on the buoyancy chamber but above the level of the sea, each anchoring arrangement for each leg comprising a pile driven into the sea bed, an air filled working chamber mounted on the pile and defining an orifice through which a said leg can extend into the chamber, and clamping means secured to the chamber and housed within the chamber, the clamping means clamping the leg to the pile.
Claim 3
Dependent Claim
22 words
A platform according to claim 1, wherein the chamber includes an airlock to allow access to the chamber from a submersible craft.
Claim 4
Dependent Claim
165 words
A tension leg marine platform structure comprising an air filled buoyancy chamber having an airlock, the airlock enabling access between the buoyancy chamber and a submersible craft when docked at the airlock, a deck, a plurality of columns supporting the deck on the chamber to lie above the level of the sea and providing access from the deck to the chamber, a plurality of tension legs each secured at one end to the buoyancy chamber, and a plurality of anchoring arrangements respectively for anchoring the other ends of the tension legs to the sea bed to hold the buoyancy chamber in a submerged state, each anchoring arrangement comprising a pile driven into the sea bed, an air filled working chamber mounted on the pile, and clamping means for clamping a corresponding one of the said tension legs to the pile inside the working chamber, each working chamber having an airlock enabling access between the submersible craft when docked at the airlock and the working chamber.
Claim 5
Dependent Claim
165 words
A tension leg marine platform structure comprising an air filled buoyancy chamber having an airlock, the airlock enabling access between the buoyancy chamber and a submersible craft when docked at the airlock, a deck, a plurality of columns supporting the deck on the chamber to lie above the level of the sea and providing access from the deck to the chamber, a plurality of tension legs each secured at one end to the buoyancy chamber, and a plurality of anchoring arrangements respectively for anchoring the other ends of the tension legs to the sea bed to hold the buoyancy chamber in a submerged state, each anchoring arrangement comprising a pile driven into the sea bed, an air filled working chamber mounted on the pile, and clamping means for clamping a corresponding one of the said tension legs to the pile inside the working chamber, each working chamber having an airlock enabling access between the submersible craft when docked at the airlock and the working chamber.
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) | 1979-11-02 | 1980-05-03 | 1980-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-11-02 | 1984-05-03 | 1984-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-11-02 | 1988-05-03 | 1988-11-02 | $7700.00 | Window Closed / Lapsed |