Page 42: of Maritime Reporter Magazine (May 2004)

Propulsion Technology

Converting and Repowering One Very Big Ship

When the decision was made to convert Dockwise's

Blue Marlin to the world's largest semi-submersible vessel, there were obviously many key considerations, with the re-powering of the new ship topping the list.

Wartsila was contracted for the job. which included supplying generating sets, two retractable bow thrusters and a large high-efficiency nozzle with new propeller blades for the main propulsion. Blue Marlin, originally built at CSBC in Kaohsiung. Taiwan (new- building 726) was delivered in 2000. equipped with one 6200 mm-diameter open Lips controllable pitch propeller, directly driven by a low-speed diesel engine

Vessel Particulars

Hub type / diameter Lips 4C1S / 1800 mm

Nozzle type Lips HR (high efficiency)

Propeller type Lips Controllable

Pitch Propeller

Propeller diameter 5.200 mm

Power 12.640 kW

Propeller speed 127 rpm

Number of installations One

CPP. particulars after conversion.

LMT type CS3500-671/3500MNR

Propeller diameter 3.400 mm

Propeller t\pe Lips Controllable

Pitch Propeller

Propeller speed 187 rpm

Power 4.5(H) kW

Input speed 900 rpm

Number of installations Two

Main Particulars

Length bp

Breadth

Depth

DWT

Deck area

Before 217.8 m 42 m 13.3 m 57,021 tons 7,484 sq. m.

After 224 m 63 m 13.3 m 78,000 tons 11,227 sq. m.

Blue Marlin - artist s impression after conversion.

Left: Blue Marlin in drydock at HMD. The extreme width of the vessel just fits in the dock.

Right: CPP, HR nozzle and tunnel construction after modifica- tion.

Bottom Left: Transport of the stem section with a weight of 40 tons. -.fv 1111 —

T' WAKEFIELD

An enormous challenge in the creation of this mam- moth vessel was ensuring it maintained an acceptable

Wake Field: Above is the wake field before conver- sion, to the right is the wake field after conversion. 40 Maritime Reporter & Engineering News • WAKEFIELD