This weeks interesting ship is actually a series of six new fuel-efficient seismic support/chase vessels recently ordered by Bourbon. The 53m vessels, designed by The Netherlands-based Offshore Ship Designers, will feature a fuel efficient hybrid propulsion system providing a flexible solution for a wide range of working conditions and operations including transit speed, slow speed escort and support work and a high degree of maneuverability. The vessels will be built at Dubai’s Grandweld Shipyards.
With expected delivery set for the end of 2012 the vessels will be chartered by Bourbon to CGGVeritas. They will be used to support the fleet of CGGVeritas seismic survey vessels operating all over the world, providing them with services including crew change, fuel delivery, storage, assistance and support during at-sea maintenance operations.
Operational requirements of the design include:
· Cargo runs from port to the mother ship
· Transfer of fuel, potable water, dry and refrigerated stores and general cargo to the mother ship.
· Transfer of crew to and from the mother ship.
· Accompanying the mother ship when conducting seismic operations
· Towing of the mother ship when conducting seismic operations
· Retrieval of streamer cables
Key feature of the hybrid propulsion system are:
· Two main marine diesel propulsion engines, two controllable pitch propellers in nozzles, two main gearboxes each with a PTI electric propulsion motor and three diesel driven generating sets, and two electrically driven bow tunnel thrusters.
· Diesel-mechanical mode using main engines only used for the transit operation.
· Diesel-electrical mode with main engines declutched using PTI propulsion motors powered by the gensets for chase and slow speed operation.
· Boost mode with main engines and PTI propulsion motors (powered by the gensets) engaged used for towing operation.
· Automatic push button selection between the different propulsion modes.
Additional vessel details can be found at Offshore Ship Designers website.