Compact semi-submersible vessel launched
The launch of the “CSS Derwent” at the shipyard in Indonesia
The newbuilding is based on a concept that has been developed by STX Marine, Hallin Marine, Minnow Marine Projects Limited and M3 Marine. The objective of the concept was to connect the capabilities and low-motion behaviour of a semi-submersible vessel in the smallest feasible form with an industry-leading design in terms of operability. Primary functions of the newbuilding will be well intervention, well stimulation and subsea installations.
The “CSS Derwent” is a twin-hulled vessel of a semi-SWATH (small waterplane area twin hull) configuration, and features diesel-electric propulsion with DP-3 capability. One azimuth thruster at the end of each hull produces a transit speed of up to 12 knots. The twin-hull platform provides a large working deck with a long laydown area. Classed by the American Bureau of Shipping (ABS) as a column-stabilised drilling unit, the newbuilding has space for 152 persons and an endurance of 45 days.
The vessel is fitted with a 150-tonne AHC (active heave compensated) subsea crane and a 160-tonne AHC guided modular handling system operating through a moonpool, as well as a 120-tonne pallet skidding system. For the support of subsea operations two ROV handling systems are provided, one through another dedicated moonpool and the other over the starboard side.
