Additive manufacturing gains importance in US Navy submarine construction

The US Navy is increasingly relying on additive manufacturing to make the construction of submarines more efficient and speed up important maintenance processes. The background to this is the delay in the production of the Columbia and Virginia-class submarines, which are up to 16 months and three years behind schedule respectively. In light of the AUCUS agreement, under which the US is to deliver three Virginia-class submarines to Australia, this development is a challenge to national security.

Rear Admiral Jonathan Rucker, the Navy’s senior buyer for attack submarines, emphasized in a hearing before the House Armed Services Subcommittee: “We cannot meet the demand to be able to support building the submarines we need, as well as supporting sustainment, without going to additive manufacturing.”

A key factor is speeding up production and controlling supply chains. Currently, the casting process is a bottleneck, especially as China is the world leader in casting production and produces significantly more than the USA. With the expansion of additive manufacturing in the USA, these dependencies can be reduced.

The use of 3D-printed parts has already proven its worth. For example, Hunt Valve, a Fairbanks Morse Defense company, was able to develop a 70-pound valve assembly that was installed in a submarine for the first time. This manufacturing method shortened production and delivery times by two thirds. By the end of 2024, the Navy plans to install nearly 100 metal additive manufacturing parts in submarines. Companies such as HII and General Dynamics Electric Boat are also relying on this technology to procure components for ships such as the USS Oklahoma.

Additive manufacturing has not only shortened production time, but also reduced the scrap rate. Copper-nickel components, which are traditionally produced by sand casting, often have high porosity and scrap rates. 3D-printed valve bodies, on the other hand, have a much higher first production success rate. In addition, this approach reduces material consumption, as only the required material is built up layer by layer.

The use of additive manufacturing in shipbuilding has expanded from small parts to large-scale components. This development promises progress for the defense industry supply chain and the US Navy’s long-term shipbuilding strategy.