Our recent article on a 3D printed underwater scooter ended with a prediction that we’ll be seeing a 3D printed submarine soon. While we’re still not quite there, a significant step in that direction was achieved over the summer when thyssenkrupp Marine Systems’ 3D printed components for submarines received safety and quality approvals for serial production.
This makes the thyssenkrupp TechCenter Additive Manufacturing the first 3D printing manufacturing center in the world to receive manufacturer approval from DNV GL, the global society that provides accreditation and certification processes to several industries, including maritime, renewable energy, healthcare, and others. Manufacturing certifications ensure processes and end parts meet current industry standards for safety, functionality, repeatability, and spare part replacement protocols.
To demonstrate how AM could benefit the submarine sector, engineers chose to re-engineer a valve block optimized for 3D printing. It’s common to re-engineer old parts when moving their manufacturing to AM because more ideal geometries are available with 3D printing; for a refresher on this concept, check out our article on DFAM (designing for additive manufacturing). The project goals included reducing weight, improving flow behavior to reduce noise, low material permeability, and better media management. By using generative design and flow simulations, the ideal pipe runs could be mapped out and tested in the design phase. That translates to lots of time and money saved during the prototyping phase.
3D printing opens up completely new potentials for us. In the design engineering, we no longer have to consider the limits of conventional manufacturing processes everywhere. In this way, we give our customers more freedom in the design of the boats. At the same time, we can produce components faster and more cost-effectively. Bringing the necessary expertise and equipment to serve us in Kiel is the prerequisite for being able to make smaller batches quickly and easily in series in the future. Dr. Luis Alejandro Orellano, COO of thyssenkrupp Marine Systems
The printed valve block reduced the number of parts in the assembly while achieving a weight reduction of 83% from 13.3kg to 1.1kg as well as a space reduction of approximately 20%; weight reduction of components means that the load of the sub can be increased. Additionally, permeability was reduced by using a 1.3964 chromium-nickel alloy. The component was also produced with a lead time of only one year, which is substantially shorter than the industry standard of five to seven years. The plan is to focus first on manufacturing small batches for submarines but they’ll also be looking to produce spare parts in the same manner.
Featured image courtesy of TKMS