Naval Group and Centrale Nantes 3D print the world's first hollow spiral

Last year, we reported that the French defense contractor Navy Group, in cooperation with the French engineering school Centrale Nantes, developed the world's first full-size 3D printed military propeller, and now the same collaboration has produced the world's first 3D printed hollow propeller blades. The blade case is part of the European H2020 project, and the RAMSSES project (Implementation and Demonstration of Sustainable and Efficient Advanced Materials Solutions for Ships) is funded by the European Commission to reduce the environmental impact and manufacturing operations of large vessels using new technologies such as 3D printing. .

Using Wire Arc for additive manufacturing (WAAM), the group plans to print 3D steel propellers up to 6 meters in diameter, but the prototypes tested were produced in one-third of the scale. The blade weighs about 300 kilograms and takes less than 100 hours to make. Their analysis shows that full-size 3D printed blades can reduce weight by 40%! Not only does this require less material, but it also reduces the load on the engine, which can further reduce fuel consumption and thus the ship's environmental impact. In addition, the improved blade design of Sirehna (a subsidiary of Centrale Nantes and Naval Group) improves efficiency and durability while reducing radiated noise and vibration that negatively impacts marine animals.

Patrice Vinot, Propeller Packaging Manager of the NASS Group's RAMSSES project, presented some exciting ideas for proof-of-concept: “Although additive manufacturing is increasingly occurring in industry, the programming and design of complex parts, such as marine propeller blades, The representative is a huge challenge for our team and partners. This new case study reveals the potential of this process means that we now expect tomorrow's propellers to have unparalleled performance. Participate in projects such as RAMSSES and coordinate our academics And the network of industry partners will enable us to bring 3D printing to shipyards for a long time."

Professor Jean-Yves Hascot is the head of the Centrale Nantes rapid manufacturing platform and an international expert in additive manufacturing. He explained: “On the rapid manufacturing platform, additive manufacturing has been developed for the past 35 years. All these years of research have been passed. Realized by projects like RAMSSES, RAMSSES represents the real transfer of our technology to industrial environments. “The naval industry is slowly adopting 3D printing to ensure a smooth sailing in the future”.