Marine riser system with dual purpose lift and heave compensator mechanism

Patent · Tue Dec 04 04:00:00 EST 1979

OSTI ID:5290934

Wetmore, S B; McNary, J F; Person, A

Apparatus for drilling a well at a location submerged below a body of water includes a buoyant foundation structure. The foundation structure is floatable on the surface of the body of water and is subject to vertical motion in response to waves and the like. A riser handling and tensioning mechanism is mounted to the foundation structure and is operable for moving a riser pipe along a substantially vertical line from and to the foundation into and out of connection with the submerged location. The riser handling and tensioning mechanism is also operable for applying tension to a riser pipe connected to the submerged location. The handling and tensioning mechanism includes vertically disposed hydraulic rams mounted to the foundation structure. Holding means are releasably engageable with a riser pipe adjacent its upper end and are connected to the rams for movement along the riser line by the rams. The rams have an active operating mode in which they are operable to lower and raise a riser pipe along the line into and out of connection of the lower end of the riser with the submerged location. The rams also have a passive operating mode in which they are operable to apply a selected upward force to a riser engaged in the holding means and connected to the submerged location during vertical motion of the foundation structure. 4 figures.

• Assignee: Global Marine, Inc.
• Patent Number(s): US 4176722
• OSTI ID: 5290934
• 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
423000 -- Engineering-- Marine Engineering-- (1980-)
DESIGN
DRILLING
MARINE RISERS
MATERIALS HANDLING
NATURAL GAS WELLS
OFFSHORE DRILLING
OIL WELLS
PIPES
USES
WELLS