Headlines exclaim how 3D printing, also known as additive manufacturing, has changed the way products are envisioned and created on a global scale. But what someone might not know is how additive manufacturing is helping Norfolk Naval Shipyard (NNSY) innovate and improve its ability to support the U.S. Navy.
Opportunities to utilize this pioneering technology range from simple ship alterations, to complex issues such as executing a hull replacement on USS La Jolla (SSN 701) or identifying cost-saving methods to overhaul the new Gerald R. Ford class of aircraft carriers.
"When engineers have a new design to try, instead of getting a whole piece made out of metal or plastic by the toolmakers or machinists, they can say, “Pop this in the 3D printer.” That's the purpose of additive manufacturing — try the design out, see how it's going to fit up, and then we move onto the manufacturing process," said Bill Harrell, NNSY rapid prototype program lead. "If someone says, 'I need to see how that motor's going to fit up on top of that pump housing to see if the clearances are good, or that the bolt holes are going to line up, or to see if the concept is going to look good, 3D printing is perfect."
The Rapid Prototype Lab's 3D printer adds layer upon layer of plaster polymer to build a solid project that can be touched, held and studied.
"We take a computer-aided design drawing and transfer it to a laptop that then transfers the parameters and the dimensions to the 3D printer and pretty much tells it what to print," Harrell explained. "The printer manufactures the part, the part goes to a cleaning station where it's treated, and you've got your 3D part."
Shipyard products produced via printer take anywhere from a few minutes-think a NNSY commemorative coin made out of plaster polymer instead of metal-to several hours, such as a multi-piece pipe-closure device that quickly secures exposed pipes. For the larger scale jobs, the printer effectively makes wooden and metal shipyard mockups, that consumed material and expended labor hours, a thing of the past.
For the complex availability on USS La Jolla beginning in spring 2015, the Rapid Prototype Lab produced 3D prints of the hull to determine how to best replace it. "It's a good hands-on conversation piece, to proactively start talking and seeing how we're going to cut the middle of the boat out," said Harrell. "When ship-fitters get around the table and start looking at it, they might ask, 'how's that going to work?' and catch some things that still need to resolved."
The 3D printer is already helping to determine ways to service the new Gerald R. Ford class of aircraft carriers. "Rather than making something out of metal, which would probably take two to three months just to see fit-up purposes, we print out a 3D part and we can put it on a mockup," said Harrell. "It's really rapid prototyping or proving a concept for actual use, which can save time, material money and labor."
The shipyard's Nuclear Engineering and Planning department's lab created models of ship alterations, giving workers an example to plan from which ultimately saved both money and time. Riggers would use a ship alteration mockup made of wood and then train with it for the riggers.
"They figured this came to $11,000, and they wanted a cheaper way to do it," said Don Gauthier, rapid prototype lab sheet metal mechanic. "After we printed them a model, the riggers and engineers realized it wouldn't fit. We did another print that would fit, which saved them $3,000 in rework. They looked at it, figured out how to maneuver it and rig it in. The piece was in in an hour, rather than a couple of days."
The 3D printer is ensuring a promising future for continuous training and development at the shipyard. The lab has produced a prototype tool for Shop 71 (Painting/Blasting) to use as a training aid for the Navy's new process of removing paint by laser, known as laser ablation. The tool, known as an End Effector and looking like a hybrid of a handgun and a DustBuster, is estimated to save $3,000 in training hours and is expected to increase first-time quality.
"Trainers wanted something other than the actual laser so we built them a model with a 3D printer," said Gauthier.
Harrell said once NNSY got a 3D printer, the buzz really started getting out and the other three shipyards followed suit. Since then, Pearl Harbor Naval Shipyard purchased an identical 3D printer; Portsmouth Naval Shipyard has several 3D printers; and Puget Sound Naval Shipyard now has 3D printers in their engineering departments.
"You can see, down the road in five years, where [NNSY] engineering and planning would have their own prototyping area," said Harrell. "It's starting to change the mindset of how we think as a shipyard. We're not just a shipyard [of personnel] that goes in a bilge or tank to get dirty and turn wrenches; we're skilled craftsmen who want to stay up with technology."