September 7, 2010
Stone Marine NPT propellers promise increased efficiency
Birkenhead, U.K., headquartered Stone Marine Propulsion (formerly Stone Manganese Marine) reports continuing success for its NPT, or "New Profile Type," propeller.
This type of propeller, originating from Japan, incorporates cavitation friendly section profiles to reduce the blade surface area and increase propeller efficiency. Additional benefits include reduced propeller weight and inertia, which can lead to savings further up the propulsion train.
Recent contracts for the Stone Marine NPT propeller include DS Norden's newbuildings at the Chinese shipyards Guangzhou Longxue and Jiangmen Nanyang. In these vessels, overall fuel consumption will be reduced by about 11 percent as a result of the owner's revision of the main engine specification and the adoption of NPT technology.
Stone Marine Propulsion is also working with DS Norden on the upgrading of existing units within its fleet.
A further more long standing reference is Guangzhou Shipbuilding International's continuing supply of a series of 39 k tankers to A.P. Moller, again fitted with NPT propellers.
The NPT propeller has also been endorsed by the well known Danish naval architectural consultancy Grontmij Carl Bro, which now specifies it as standard for its Seahorse class of 35 k bulk carriers.