Paul Ross Erb

US Patent:

47689846, Sep 6, 1988

Filed:

Apr 15, 1985

Appl. No.:

6/723407

Inventors:

Joao G. de Oliveira - Houston TX
Arthur W. Morton - Houston TX
Paul R. Erb - Houston TX
Michael S. Triantafyllou - Cambridge MA

Assignee:

Conoco Inc. - Ponca City OK

International Classification:

B63B 2218

US Classification:

441 21

Abstract:

The present invention provides a service buoy for performing direct wireline maintenance of a subsea well. The buoy is maintained in position over the well by a rigid riser kept under tension and which allows for the well re-entry. The primary buoyant body of the buoy is maintained permanently submerged and a truss structure presenting the minimum surface area to the action of wind and waves extends above the sea level to support a small deck from which the wireline work can be performed. The centers of gravity and buoyancy for the buoy are in close proximity so as to minimize lateral surge and sway motions of the installed buoy.