Patent ID: 7044817

Claim:
An anchoring system for holding a vessel during loading or unloading, comprising: a surface buoy; an adjustably ballasted subsea buoy with swivel positioned at a subsea buoy depth at which the subsea buoy can be raised to the surface by adjusting the ballasting; a mooring line connecting the surface buoy and the subsea buoy; at least one anchor secured in the sea floor; for each anchor, a respective anchor line extending from the anchor to the subsea buoy with slack sufficient to allow raising of the subsea buoy by adjusting the ballasting; at least one vessel loading and unloading pipeline connected to the subsea buoy; and at least one first clump weight attached to at least one of the anchor lines, each first clump weight being positioned above the sea floor to provide a position-holding force at a vertical height such that, upon buoyant failure of any device from the subsea buoy to the surface buoy, including the surface buoy itself, the first clump weight will sink to the sea floor, the vertical height being no greater than the subsea buoy depth; whereby, for an arbitrary load in the pipeline, the subsea buoy can by ballast adjustment be brought up to the surface and whereby the vessel can be connected or disconnected from the anchoring system all operating conditions without adjustments in the anchoring system.