Naval group, French defense contractor and French engineering school Centrale Nantes printed the first demonstrator of hollow propeller blades by metal additive manufacturing as part of the European H2020 project, RAMSSES. This project aims to reduce the environmental impact of the vessels. Both parties of the project are taking the lead on the production of innovative propeller demonstrators to enhance the vessels’ operational capabilities.
Mainly, Centrale Nantes and Naval Group are using manufacturing to design the large parts, as propellers of 6m in diameter, which wouldn’t be able to produce with traditional means.
Moreover, the Wire Arc for Additive Manufacturing (WAAM) process allows for the printing of large parts and paves the way for the production of propellers with more complex geometry.
The one-third scale hollow blade demonstrator that reflects a container ship’s propeller, was printed in stainless steel in less than a hundred hours and weighs approximately 300kg.
The team’s skills highlight that weight gains of more than 40% will be accomplished in comparison to conventional processes.
Sirehna, a Centrale Nantes spin-off and subsidiary of Naval Group, is responsible for the blade design aiming to enhance propeller energy efficiency and decrease the environmental impact.
Concluding, Sirehna’s work has resulted to optimizing the blades efficiently, and reducing radiated noise and vibrations, as well.