Rocks & mirror
WÄRTSILÄ
Encyclopedia of Marine and Energy Technology

CRP-Azipod propulsion of the ferries AKASHIA and HAMANASU

marine

According to Significant Ships of 2004

The ferries AKASHIA and HAMANASU built by Nagasaki Shipyard (MHI) are the first vessels provided with the CRP-Azipod propulsion. The concept, initially developed by ABB with Samsung for ultra large container vessels, consists of a pod propulsion unit with stainless steel FP propeller, operating behind a single, conventional CP propeller. The two propellers face each other in a single-skeg hull form, and are contra-rotating.

The Kawasaki-designed main propeller is driven mechanically by two 12,600kW Wärtsilä 12V46C main engines, linked through a twin-input/single-output gearbox. Two engines of similar sizeare also installed to drive the two 12,200kW ABB alternators which provide power for the steerable 17.6MW Azipod unit, and for general ship service power. The third Daihatsu/ABB alternator set producing 2760kW is also fitted for auxiliary use.

During sea trials, the vessel achieved the speed of 32knots. The full-scale comparison between the new vessel and similar twin-screw vessels operating earlier on the same route, demonstrated a 20% fuel saving and striking improvement in exhaust gas emissions. In addition, the pod unit provides exceptional manoeuvrability, especially in port. Operating costs of the new vessels are expected to be further reduced through lower maintenance costs.