Additive Manufacturing for Obsolete Naval Components

Today’s geopolitical climate has bolstered NATO-member militaries to levels not seen since the coalition’s inception. Maintaining the combat readiness of all NATO navies is a costly and complicated undertaking, with wavering supply chains and aging naval architecture being the primary technical challenges.

Every NATO navy is now exploring life-extensions and how to get more from aging naval assets. As these ships remain in service longer than their originally intended design life, the maintenance burden continues to increase.

A critical issue is the replacement of obsolete or time-expired parts, such as valves, are no longer available through traditional supply chains. To address this, the Department of National Defence (DND) initiated efforts to investigate the use of additive manufacturing (AM) to develop prototype valve designs that meet existing technical and operational requirements.

Enginuity’s Mechanical team, in partnership with defence stakeholders, conducted a research and feasibility study into how AM could be incorporated into producing replacement valves. After evaluation, Selective Laser Melting (SLM) was chosen as the preferred AM technology for the following reasons:

• High precision and ability to meet tight dimensional tolerances.
• Strong mechanical properties, comparable to conventionally manufactured parts.
• Access to corrosion-resistant materials such as stainless steel and Inconel, critical for marine environments.
• Reduced manufacturing timeline by 1/8, resulting in decreased lead time
• Wide commercial availability and a proven track record in marine, aerospace, and defence industries.

Note: There is also a similar variant known as Direct Metal Laser Sintering (DMLS). Although the process differs slightly, the performance and material properties are effectively equivalent, and thus both are suitable.

To assess whether the new AM-produced valves would meet required performance thresholds, Enginuity’s team used FEA to verify compliance, and to adhere to standards of which the original parts were designed.

The study demonstrated the feasibility of using AM for obsolete naval valves, specifically leveraging SLM to produce corrosion-resistant, mechanically robust replacements on demand. While testing and requirements validation remain challenges, this project highlighted the potential of AM in defence applications.

It further emphasised that different projects may require different AM technologies, and that a structured selection matrix is valuable for evaluating future cases.