IHI Develops Steerable Type CRP Propulsion Unit
Ishikawajima-Harima Heavy Industries Co., Ltd. (IHI) has marketed a newly-developed steerable-type contra-rotating propeller (CRP) propulsion unit, IHI CRP- DUCK, for coastal cargo ships and tankers.
The IHI CRP-DUCK is a hybrid propulsion unit of the Duckpeller and the IHI-CRP system. The Duckpeller, which was developed by IHI in 1967, is a propulsion unit that can control the thrust direction in 360 degrees, and is used for tug boats and others. The CRP is a pair of propellers contra rotating to increase thrust force, or reduce energy consumption, and is used for merchant vessels.
The new propulsion unit demonstrates superior maneuverability and economy in ship operation by steering function with large thrusting force and less energy consumption. Berthing and unberthing become safer and more efficient in narrow and congested ports, requiring fewer harbor workers.
Main features are :
・ Increased maneuverability : The beam thrust facilitates berthing and unberthing. Straight astern can be achieved.
・Low energy consumption: Increased propulsion efficiency decreases energy consumption by 10% while reducing emission of air pollution substances.
・Low noise and vibration : Excitation force has been reduced by 40%, comfortable ambience on board the ship can be achieved, and service life of equipment is prolonged. Vibration is low during going astern or turning.
・Packaged propulsion and steering unit: Propellers, propeller shafts, reduction gear, and steering device are all built in one unit. On-board mounting and outfitting of the unit are carried out easily.
・Easy maintenance : The propulsion unit is easily removed for onshore maintenance. Installation of the unit is possible after the ship is launched, making ship construction schedule flexible.
・Minimized engine room space: Requirement for the engine room space is minimized, providing wider cargo hold space and/or accommodation quarters.
PRINCIPAL PARTICULARS
(for use in 1,600-dwt to 2,100-dwt ships)
Rated input power……………1,800PS
Rated input revolution……………750rpm
Fore propeller……………4 blades
Aft propeller……………5 blades
Fore propeller diameter……………2,510mm
Aft propeller diameter……………2,220mm
Propeller revolution……………225rpm
Propeller material……………Ni-AIBC
