Navy clears new 3D printed metal parts protocol for submarines
New technical requirements replace part-by-part engineering review for AM substitutes of cast and wrought components
The U.S. Navy has released technical requirements that establish a repeatable pathway for substituting additively manufactured metal parts for legacy cast and wrought components across submarine construction, maintenance and repair.
Project Peculiar Document (PPD) was authorized for immediate use in submarine design, construction, overhaul and repair. In comparison, under earlier practice, exchanging a conventional part for an AM equivalent required a separate engineering assessment for each component, manual drawing modifications and repeated first-article testing.
“This is exactly the type of barrier we must remove if we are going to unlock 21st century technology to get our submarine programs on plan and ahead of the threat,” said Vice Adm. Robert Gaucher, Director of Submarine Programs.
“Additive manufacturing gives us a tool to get after supply chain constraints and part obsolescence by reducing the time it takes to get critical capability to our warfighters. This directive hands our engineers, shipbuilders, and suppliers authority to execute at scale.”
For high-consequence applications, including Level I material control and SUBSAFE systems, AM materials will still remain subject to applicable Navy quality requirements, with additional tracking and non-destructive inspection layered on top.
“Moving faster does not mean accepting less,” Gaucher said. “As we scale our advanced manufacturing capabilities, we will relentlessly enforce the safety and quality standards our crews rely on. Our objective is clear: embrace advanced manufacturing to solve hard problems, update or removal of legacy processes, and deliver quality submarines safely.”
The Navy has been positioning AM as an alternative source for long-lead parts for some time now, as a route around suppliers that have left the market, and a hedge against obsolescence before it reaches fleet availability.
AM metal components were already in service aboard USS Washington and USS Nevada, and the Navy has also confirmed that they have performed without fault in deep-sea operation.
