Tension leg platform and installation method therefor

Patent · Tue Oct 25 04:00:00 EDT 1988

OSTI ID:6543391

Gunderson, R H

This patent describes a tension leg platform, comprising: a foundation element secured to an ocean bottom location; a plurality of elongate, substantially vertical tethers, each of the tethers having a lower end secured to the foundation element and an upper end which reaches a position a preselected vertical distance below the ocean surface; a buoyant hull positioned at the ocean surface above the tethers, the hull having a free floating draft which is less than the preselected vertical distance, whereby the tethers can be preinstalled and the hull can subsequently be positioned over the tethers without interference between the tethers and the hull, the hull defining a plurality of recesses extending vertically upward into the hull from a lower surface of the hull; a plurality of rigid tether extenders, each positioned within a corresponding one of the recesses; means for controllably fixing the vertical position of each tether extender within the corresponding one of the recesses; and means for connecting and disconnecting each tether extender to the corresponding one of the tethers while the corresponding tether is secured to the foundation element.

• Assignee: Exxon Production Research Co., Houston, TX
• Patent Number(s): US 4780026
• OSTI ID: 6543391
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
03 NATURAL GAS
030300 -- Natural Gas-- Drilling
Production
& Processing
42 ENGINEERING
420206 -- Engineering-- Mining & Drilling Equipment & Facilities-- (1980-1989)
423000 -- Engineering-- Marine Engineering-- (1980-)
DESIGN
FABRICATION
FASTENERS
FOUNDATIONS
INSTALLATION
JOINING
MATERIALS HANDLING
MECHANICAL STRUCTURES
NATURAL GAS WELLS
OFFSHORE PLATFORMS
OIL WELLS
POSITIONING
SUPPORTS
WELLS