OFFSHORE PLATFORM

• US 3,657,895 A
• Filed: 02/12/1971
• Issued: 04/25/1972
• Est. Priority Date: 02/12/1971
• Status: Expired due to Term

• Current Assignee: Chevron Research Company (Chevron Corp.)
• Original Assignee: Rex V. Phelps
• Inventors: Phelps, Rex V.
• Primary Examiner(s): Shapiro, Jacob
• Application Number:
  US05/114,809
• Time in Patent Office: 438 Days
• Field of Search: 61/45.5,46,.5,1,52,69 175/7,8,9
• US Class Current: 405/210
• CPC Class Codes: E02B 17/02 placed by lowering the supporting construction to the bottom, e.g. with subsequent fixing thereto
• CPC Class Codes: E02B 2017/0086 Large footings connecting several legs or serving as a reservoir for the storage of oil or gas
• CPC Class Codes: E21B 15/02 specially adapted for underwater drilling E21B15/04 takes precedence

Abstract

A platform for offshore oil wells having a curbing around the periphery of the deck of the platform. The deck slopes downwardly from the curbing into a central opening to drain all oil spilled on the deck into the opening. A cylindrical sleeve open at its lower end to admission of water extends downwardly, preferably to the marine floor, from the opening. The diameter of the sleeve is at least as large, and preferably in the range of 20 to 50 feet, as the opening whereby all oil or other liquids draining into the opening is confined within the sleeve. The platform can be entirely of steel, steel framework mounted on a concrete substructure, or of concrete modules assembled at the well site.

Claims

1. A platform for an offshore oil well in a body of water comprising support means engaging the marine floor for supporting a deck at a height over the water surface of the body of water above the level reached by waves, a curbing around the periphery of the deck, an opening extending downwardly through the deck for well casing, said opening having a size providing space around the well casing for the flow of liquids, a sleeve extending downwardly from the opening in the deck at least substantially to the marine floor, the opening in the sleeve being at least as large as the opening in the deck whereby oil draining through the opening in the deck is confined within the sleeve, and conduit means for allowing flow of water into and out of the lower end of the sleeve, said deck sloping downwardly from the curbing to the opening in the deck.

2. A platform for offshore wells as set forth in claim 1 in which the sleeve has a diameter of 15 to 50 feet.

3. Apparatus as set forth in claim 2 in which the sleeve extends downwardly all of the way to the marine floor.

4. Apparatus as set forth in claim 2 including pumping means for withdrawal of liquid from the sleeve at substantially the water level of the body of water.

5. A platform for offshore wells as set forth in claim 4 in which the support means is steel framework.

6. Apparatus as set forth in claim 4 in which the support means comprises a concrete substructure resting on the marine floor and having a central opening extending downwardly therethrough to the marine floor, steel framework mounted on the concrete substructure and extending upwardly to the deck, said sleeve extending downwardly into the central opening in the concrete substructure, and sealing means preventing leakage between the sleeve and the central opening in the concrete substructure.

7. Apparatus as set forth in claim 6 in which the conduit means comprise a pipe opening at its lower end into the central opening in the concrete substructure and extending upwardly through the opening to the sleeve and outwardly through the sleeve above the level of the concrete substructure.

8. An offshore platform as set forth in claim 4 in which the support means comprises a plurality of stacked annular concrete modules latched together to form a column with a central opening extending therethrough from the deck to the marine floor, the central opening in the column constituting the sleeve extending downwardly from the opening in the deck.