دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: a system consisting of a beacon positioned on the seafloor to transmit an acoustic signal, a set of three or four hydrophones mounted on the hull of a floating offshore drilling vessel to receive the signal, and a position display unit to track the relative positions of the rig and the drill site. Monitoring of the display unit aids in accurate positioning of the rig over the site.

n: the distance from the normal level of the sea surface to the bottom of the hull or base of an offshore drilling platform or rig.

n: The distance from normal sea level to drill platform when marine drilling.

the clearance between the highest water surface that occurs during the extreme environmental conditions and the underside of the deck.

n: (1) the extreme width (breadth) of the hull of a ship or mobile offshore drilling rig. (2) a walking beam. See walking beam.

n: the distortion of the hull of an offshore drilling rig when the bow and the stem are lower than the middle, caused by wave action or unbalanced or heavy loads. Compare sagging.

n: the pressure exerted on the bottom hull of a columnstabilised semisubmersible drilling rig when the hull is submerged to drilling water depth.

n: the greatest overall dimension measured perpendicular to the longitudinal centreline of the hull of a mobile offshore drilling rig. Also called the beam.

n: a jackup drilling unit in which the drilling rig is mounted on two cantilevers that extend outward from the barge hull of the unit. The cantilevers are supported only at the barge end. Com- pare keyway.

n: the middle line of the hull of a mobile offshore drilling rig from stem to stem, as shown in a waterline view.

n: the foremost bulkhead that extends from the bottom to the freeboard deck of a drill ship. It keeps the main hull watertight if a collision occurs.

n: A kind of fissile and indifferent bridging material, usually used as plugging agent of honeycombed leakage zone.