Maritime energy contractor Hallin Marine has commissioned a $110million, ground-breaking semi-submersible, subsea-operations vessel to be named the CSS Derwent.
The 84m “compact semi-submersible” (CSS) is the culmination of a five-year project designed to deliver “large boat capability” at the price of a much smaller vessel, with a primary focus on light well intervention.
Hallin and its partners say they have achieved the goal that has proved elusive to the subsea industry by designing a vessel that uses a semi-submersible-style hull to provide exceptional sea-keeping characteristics, increase deck space and provide good project load-carrying capacity.
The result is the CSS Derwent, a dynamically-positioned class 3 (DP3) vessel fitted with a 200-tonne multipurpose tower and a 150-tonne active heave crane, both operational to depths of 3,000m (10,000ft), along with two deepwater construction-class ROVs.
Hallin says it is confident that the CSS Derwent, which will have two moon pools, accommodation for 152 personnel and an operational deck space comparable with a 120m vessel, will set new levels of performance, sea-keeping and operational flexibility for a vessel of its size.
The company claims that key to the diesel-electric-powered CSS Derwent’s success will be its strong financial advantage over larger vessels of a similar capability.
Speaking at the signing of the build contract with Drydocks World in Singapore, Hallin’s chief executive, John Giddens, said the CSS Derwent showed faith and optimism in the subsea oil&gas industry.
“There are very few new-build vessels being ordered for our industry, and certainly none as exciting or as ground-breaking as the CSS Derwent,” he said.
“She will have the capacity of a 120m vessel but not the cost, either initially or operationally.
“We are delighted to sign the contract to have the CSS Derwent built. The level of interest in her since we started talking about the concept has been huge, and it is easy to see why – the CSS Derwent is designed to have the operational capacity of a large DSV or MSV, or traditional semi-submersible, but as a lower-cost alternative.
“We came up with the concept some five years ago and the design development has been a very carefully considered commercial and technical process, backed by extensive testing, development and equipment selection.
“We are confident that the outcome is a cost-effective vessel with a high level of capability that significantly exceeds that of similar-length units and with an improved weather working capability.”
CSS Derwent is designed to be MODU (mobile offshore drilling unit) compliant and, when interfaced with the 3,000m depth capability lubricator systems owned by Hallin’s parent, Superior Energy Services, is expected to provide a one-stop shop for subsea light well intervention, inspection repair and maintenance, plus subsea construction support.
The 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 new vessel is scheduled to join the Hallin fleet during Q2 2012 and is the third asset that Drydocks World has built for the company. The other two are the monohull support vessels, Ullswater and Windermere.