Royal Van Voorden Castings has finished a large project consisting of four stainless steel propellers. The stainless steel propellers are the largest the company has made so far.
The propellers, of diameters 2900 mm and 3500 mm, have a combined weight of over 25 tonnes and will be used for two contra-rotating podded drives. The total system will be used for a Canadian ferry that will operate in arctic conditions (with ice class notation 1AS).
Thinner Blades and Less Cavitation
For some decades now, ships propellers have been made of bronze. Because of the tough conditions in which the Canadian ferry will be sailing, it was necessary to use stainless steel for the propellers. This resulted in thinner propeller blades and, thus, an increase in performance and a lower fuel consumption. Furthermore, the stainless steel reduces cavitation.
Ice Class 1AS
The ferry will be built by the Italian yard Fincantieri on behalf of Société des traversiers du Québec and will be transporting passengers throughout the year. Because of the harsh local conditions, the propellers have to be able to cope with big pieces of ice. Therefore, the ship is classified with the heavy ice class 1AS.
Van Voorden is one of the few foundries in the world that is able to cast stainless steel in these dimensions; both are surveyed and approved by Lloyd's Register. The propellers were manufactured for the company of Steerprop Ltd, the producer of azimuthing propulsion systems (pods).
