Rilsan® Polyamide 11 is used to manufacture a turbine in direct contact with drinking water

When it comes to product development, additive manufacturing has an important role to play, allowing for quicker iterations, leading to shorter production times. Many design offices have equipped themselves with 3D printing solutions to accelerate innovation and bring to the market differentiated products faster. This is the case of Novall, a French company specialising in the design of industrial products: 3 years ago it opened an entity dedicated to additive manufacturing, and today uses this technology to design and produce small series adapted to the needs of its customers. The company thus offers tailor-made solutions that would be too expensive to produce using injection molding for example. The entity works with a powder sintering process and Arkema’s Rilsan® Polyamide 11, a 100% bio-source material based on castor oil. The unique chemical and mechanical properties of this material allow Novall to design ACS (French Certificate of Sanitary Compliance) certified components that are in direct contact with drinking water, such as hydrogenators or filtration solutions.

Novall first invested in an additive manufacturing machine a few years ago as an alternative to outsourcing, in order to produce more quickly and locally. Novall is working with Save Innovations, a company that provides electrical power to equipment used to modernize drinking water networks. In France, the network has a lifespan of about 50 years, with a leakage rate of 20%: its modernization is therefore an important issue. This is why it decided to design Picogen, a patented pico-turbine consisting of a turbine and regulator that optimizes electricity production. Therefore, Picogen enables the production of the electricity needed to supply the equipment used to modernize drinking water networks. The solution was installed in 2018 on the Eau de Paris’ network.

Picogen is a patented pico-turbine consisting of a turbine and regulator that optimizes electricity production

The use of Rilsan® PA11 in turbine design

After carrying out some tests on different 3D printing processes, the company opted for selective laser sintering, and in terms of materials, PA11 for its mechanical and chemical properties. The material has very low water absorption properties, as well as excellent mechanical and resistance properties: it is ductile and shows a great impact resistance. It is also compatible with direct contact with drinking water while PA12 for example requires a special coating and revaluation. Ronald Bosch, CEO of Novall, explained: “We were hesitating between PA12 and PA11, but in various tests we found that PA11 performs better in water.” A material that proved to be ideal for the series production of a connected pico-turbine.