Moonpool guidance system for floating structures

Patent · Tue Apr 23 04:00:00 EST 1985

OSTI ID:5358181

Gregory, E W; Danielson, T R; Eberwine, D A

A guidance system for centering and guiding various drill strings or risers within a moonpool of a floating structure, e.g. a caisson vessel. The system comprises one or more guidance vehicles. Each vehicle is movably mounted on a separate track. The tracks, in turn, are spaced about the moonpool wall and extend vertically along the wall of the moonpool from the top of the moonpool to a point near its bottom. Each vehicle has a frame and means to mount the frame on its respective track. Two side arms and a center arm are pivotably mounted on the frame and are movable between a closed position and an open position. Mounted at the outer end of each of the arms is an interchangeable workhead assembly which engages a drill string or riser to center and guide the drill string or riser when the arms are in their closed position. Individual lines controlled by winches above the moonpool are attached to each vehicle for independently raising and lowering that vehicle within the moonpool.

• Assignee: Exxon Production Reseach Co.
• Patent Number(s): US 4512409
• OSTI ID: 5358181
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
03 NATURAL GAS
030300 -- Natural Gas-- Drilling
Production
& Processing
DESIGN
DRILL PIPES
DRILLING EQUIPMENT
EQUIPMENT
HOISTING
HOISTS
HYDRAULIC EQUIPMENT
MARINE RISERS
MATERIALS HANDLING
MATERIALS HANDLING EQUIPMENT
NATURAL GAS WELLS
OFFSHORE PLATFORMS
OIL WELLS
PIPES
POSITIONING
WELLS
WINCHES