Hallin Marine commissions construction of subsea vessel with Compact Semi-Submersible hullformVessel & ROV News // May 21, 2010
The CSS design provides large vessel capability in a smaller design.
Hallin Marine has commissioned a newbuild, US$110 million, semi-submersible subsea operations vessel to be named CSS Derwent.
The 84m compact semi submersible (CSS) is the culmination of a five-year project designed to deliver ‘large boat capability’ at a price of a much smaller vessel with a primary focus on light well intervention.
Hallin and its partners claim they have achieved a goal that has proved elusive to the subsea industry by designing a vessel that uses a semi-submersible hull to provide exceptional seakeeping characteristics, increase deck space and provide good project load carrying capacity.
The result is CSS Derwent, a dynamically positioned class 3 (DP3) vessel fitted with a 200 tonne multi-purpose tower, a 150 tonne active heave crane, both operational to depths of 3,000m; along with two deep water construction class ROVs.
Hallin says it is confident that CSS Derwent, which boasts two moonpools, plus accommodation for 152 and operational deck space comparable to a 120m conventional vessel, will set new levels of performance, seakeeping and operational flexibility for a vessel of its size.
CSS Derwent is MODU compliant and, when interfaced with the Superior-owned 3,000m Lubricator systems, provides a "one-stop shop" for subsea light well intervention, inspection repair and maintenance, plus subsea construction support.
CSS Derwent was designed by STX Canada Marine Inc and has undergone extensive testing and development. The yard and equipment suppliers have been assessed through a rigorous tender process and selected on the basis of capability and proven performance.
The CSS will join the Hallin fleet during the second quarter of 2012. The project has been backed by Hallin’s parent company, Superior Energy Services; the vessel will be built at Drydocks World.
CSS Derwent key features:
• ABS Class +A1 Mobile Offshore Drilling Unit +AMS (E) DP3 UWILD Helideck
• Multi Purpose Tower with 200T SWL AHC, and 3000m hook travel
• 150T SWL active heave compensated knuckleboom subsea crane which will work in 3,000 metre depths
• 100T SWL draw works with built in deck skid system
• Combination of tower and crane gives a versatile twin deployment capability with vessel ballasted down to 14m deep water capability - enhanced stability
• Built in ROV hangers amidships and starboard house 2 off 250hp construction class ROVs, both operational to depths of 3,000 metres.
• Compact Semi-submersible hull form has been designed for greater sea keeping capabilities when in DP mode.
• Speed 10+ knots
• Deck space comparable to 120m plus vessels
• Construction and umbilical installation capability
• Large cargo deck area - in excess of 1300m˛ at 10T/m˛
• Working deck designed to give a single length run of 50m and width of 32m within easy access of the subsea crane
• Deadweight 3200T @ 8.2m
• Deck Cargo 1500T @10T/m˛
• Cargo deck free area 1300m˛
• Main generator engine 6 x 2800KW @ 900rpm
• Thrusters 4 x 3000KW; 450KN thrust.