دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: the act of maintaining a floating offshore drilling rig on even keel, regardless of weather or load conditions.

n: the condition of a floating offshore drilling rig when ballast has been added.

n: a subdivision of space on a floating offshore drilling rig, a ship, or a barge.

n pi: numbers placed on the sides or ends of a floating offshore drilling rig to indicate its draft.

n: a self-propelled floating offshore drilling unit that is a ship constructed to permit a well to be drilled from it. Although not as stable as semisubmersibles, drill ships are capable of drilling exploratory wells in deep, remote waters. See floating offshore drilling rig.

n: A specially designed ship used to drill a well at an offshore location.

n: a method by which a floating offshore drilling rig is maintained in position over an offshore well location without the use of mooring anchors. Generally, several propulsion units, called thrusters, are located on the hulls of the structure and are actuated by a sensing system. A computer to which the system feeds signals directs the thrusters to maintain the rig on location.

n: A method by which a floating drilling rig or drill ship is kept on location. A control system of sensors and thrusters is required.

n: on a ship or floating offshore drilling rig, the balance when the plane of flotation is parallel to the keel.

n: see drift bottle. floating offshore drilling rig.

n: general term used for a floating drilling rig.

n: a type of mobile offshore drilling unit that floats and is not in contact with the seafloor (except with anchors) when it is in the drilling mode. Floating units include barge rigs, drill ships, and semi-submersibles. See mobile offshore drilling unit.

n: the first casing or conductor string (generally with a diameter of 30 to 36 inches-76 to 91 centimetres) set when drilling a well from a floating offshore drilling rig. It prevents sloughing of the ocean-floor formations and is a structural support for the permanent guide base and the blowout preventers.