دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: a mobile bottomsupported offshore drilling structure with columnar or open-truss legs that support the deck and hull. When positioned over the drilling site. the bottoms of the legs rest on the seafloor. A jackup rig is towed or propelled to a location with its legs up. Once the legs are firmly positioned on the bottom, the deck and hull height are adjusted and leveled. Also called self-elevating drilling unit.