The ‘NPT’ propeller, or New Profile Technology propeller to give it its full title, is now well proven in service with over 150 already installed.
The NPT is being installed on new builds and it is also being retrofitted on existing ships providing them with significant improvements in propulsion efficiency. Whether ‘slow steaming’ or cruising at normal operational speeds the NPT propeller is optimised to provide its vessel with impressive efficiency gains.
The NPT's high propulsion efficiency has been proven many times in model testing, and service experience now backs this up. A considerable benefit is the smaller optimum diameter of the NPT. This gives more flexibility in selection of engine rpm at the design stage, and allows an even better efficiency gain because a more effective, slower turning propeller is often possible without exceeding the maximum diameter. This benefit is also advantageous for retrofitting to a de-rated engine where the number of blades and blade surface area can be lower without an increase in propeller diameter – resulting in further efficiency gains.
The NPT also has a lower blade surface area than other types, which results in a significantly lower weight. This means the cost is very competitive and often significantly lower.
While an NPT propeller provides a vessel with improved performance this can be further enhanced with the fitting of Cap Fins and you can read more about these here.