The single point mooring system. A turret mooring system consists of a number of mooring legs attached to a turret that is designed to act as a part of the vessel, allowing only for angular relative movement of the vessel to the turret, so that the vessel may weathervane. The turret may be mounted internally within the vessel or externally from the vessel bow or stern.
For an internal turret system, the turret is supported in the vessel by a system of bearings. Typically, a roller bearing is located near the vessel deck level. A radial sliding bearing is located near the keel. For an external turret mooring system, the vessel is extended to attach the turret mooring system at the end of the vessel.