Hydrex has developed a unique way to maintain ship propellers, thereby achieving maximum efficiency and increasing fuel savings by a reported 5%.
The approach requires more frequent, lighter buffing of the propeller. In contrast, the traditional technique involves letting the propeller foul and build up a calcareous growth, which necessitates polishing just once of twice a year underwater during dry-dock.
With this lengthy time-frame in-between polishing there is usually a substantial amount of growth. This requires a grinding disk, which can damage propeller blades and remove a substantial amount of metal. Over time this can also alter the shape and efficiency of the propeller, cause roughness and increase friction. In addition, it is a major source of marine pollution says Hydrex’s founding chairman.
Hydrex’s little and often approach means that the propeller is buffed before any calcareous layers build up and before cavitation erosion has a chance to occur and impact efficiency. According to Dave Bleyenberg, Hydrex Production Executive, if done correctly and regularly it can achieve 5% or more savings in fuel consumption, which more than offsets the cost of this propeller maintenance process.
Van Rompay tested the Hydrex approach on a cruise ship. While the fouling was not heavy to begin with, calculations estimated fuel savings of US $2,100 over a 30 hour trip.
The company states that a fuel saving of more than 5% was a direct result of the more effective propeller maintenance procedure.