Abstract: A mooring system for a Floating Production, Storage and Offloading vessel (FPSO) employs a vessel mounted rotatable turret and a single point mooring arrangement. The mooring arrangement includes a single anchor chain that is removably attached at a top end to the vessel, and is attached at a submerged bottom end to three sealed anchored leg chains. The anchor chain is secured to the vessel by means of a chain stopper that is centrally located in the rotatable turret, and allows the vessel to rotate freely about the anchor chain's vertical axis. One or more submerged fluid carrying risers are detachably connected to a swivel stack positioned above the mooring table in line with the rotational axis of the anchor chain so that the risers and the anchor chain will not become entangled with one another during vessel rotation.

Abstract: A mooring system for a seagoing vessel, such as an oil tanker, employs a submerged buoy and a fluid swivel joint mounted in the vessel. The buoy is submerged to a depth sufficient enough to allow the moored vessel to drift over the buoy and other mooring elements without colliding with the same. A motor drive assembly is provided for a rotating shaft in the fluid swivel joint which maintains the shaft in the same position relative to the buoy, regardless of environmental induced changes in the heading of the moored vessel. This insures that one or more flexible hoses connected between the shaft and the mooring will not be twisted if the vessel begins to rotate about the vertical axis of the mooring. Positioning the fluid swivel joint within the vessel provides easy access to the joint for maintenance or repair and shields the joint from the seawater's detrimental effects.