Norwegian shipowner Østensjø Rederi AS has placed an order with Voith Turbo Marine for two Voith Schneider Propellers (VSP) for a Platform Supply Vessel (PSV), a landmark order for the propulsion manufacturer as this is its first application on this vessel type. Designed by Norway
’s Skipsteknis, the vessel will be built in Spain
at Astilleros Gondan shipyard.
The PSV is scheduled to begin working in the beginning of 2007. The PSV will be Dynamic Positioning (DP II) capable. According to the propulsion manufacturer, a PSV driven by two VSPs requires 10 to 20 percent less power, depending on the load conditions and the sailing speed, helping to save fuel and reduce maintenance.
First model test series were carried out at Marintek in Trondheim, Norway, in February 2002. In the first test series, the power uptake of the two propulsion elements ‘contra-rotating propeller’ (CRP) and ‘VSP’ was established. Here, the VSP needed approximately 10 percent less power at various hull drafts and across the entire speed range. The second model test series at SVA in Vienna in February 2005, a test which reportedly confirmed that the R&D team had taken the correct path.
A special feature of the VSP is its roll damping capacity. At standstill and when not in full sail, the VSPs can be used to reduce the effects of high seas on the ship. This is particularly important, since PSVs are loaded and unloaded on the high seas. In such a situation, a rolling vessel would slow down the loading process or stop it altogether. The VSP in combination with the Voith Roll Stabilization (VSR) reduces this risk.