The jig is up . . . and assisting propulsion system work for Norfolk Naval Shipyard

Photo By Shelby West | Norfolk Naval Shipyard’s (NNSY) Engineering and Planning Department’s Propulsion Machinery Branch recently teamed with the NNSY Technology and Innovation Lab to design, develop and manufacture a 3D-printed stave measurement to precisely measure waterborne bearing stave widths to facilitate ship propulsion system work. NNSY’s Inside Machine Shop assisted by producing a stave standard of a known width to calibrate the jig and expedite installation jobs. From left to right: Dixie Cox, Technology and Innovation Lab Subject Matter Expert for Additive Manufacturing; Mechanical Engineering Supervisor Robb Morris; and Jessica Roberts, NNSY Technology & Innovation Community of Practice Lead/Additive Manufacturing Lead.  

PORTSMOUTH, VIRGINIA, UNITED STATES

02.09.2021

Story by Michael D Brayshaw 

Norfolk Naval Shipyard

Thanks to innovative thinking and teamwork, Norfolk Naval Shipyard (NNSY) has implemented a 3D-printed stave measurement jig for ship propulsion system work.
Driven by a need to support emergent work on a ship at one of the shipyard’s satellite locations, NNSY’s Engineering and Planning Department’s Propulsion Machinery Branch (Code 266) teamed with the NNSY Technology and Innovation (T&I) Lab to design, develop and manufacture this tool to precisely measure waterborne bearing stave widths. NNSY’s Inside Machine Shop (Shop 31) then produced a stave standard of a known width to calibrate the jig and expedite installation jobs.
“Waterborne staves are part of the bearings for the propulsion shaft line that support the shaft sections outside the dry portions of the ship’s hull,” explained Code 266P’s Mechanical Engineering Supervisor Robb Morris. “They are used as a wear surface for the shaft to rotate in while supporting the weight of the shaft and are lubricated and cooled via seawater.”
While the staves are replaceable, they must be in adherence with their corresponding NAVSEA standard drawing. Standard drawings detail items used across multiple ship classes, with bearing staves used for aircraft carriers, Ohio-class and Los Angeles-class submarines serviced by NNSY. Pointing out that the standard drawing includes 10 different sized staves of various widths, Morris said the new jig can verify all sizes when used with the standard NNSY’s Inside Machine Shop produced.
Discussing the benefits of the new tool, Morris said, “Use of the jig can identify stave discrepancies early and easily when the material arrives prior to installation. This jig is easy to use and is well within the normal tooling familiarity of any Shop 38 [Outside Machine Shop] mechanic. It can be used anywhere, is lightweight, and requires basic precision instruments to utilize.”
Creating this tool lends further credence to the mantra of necessity being the mother of invention. Given the urgency of executing the work to support the ship’s looming deployment, NNSY’s Propulsion Machinery Branch collaborated with the lab to develop the tool’s prototype within two days of starting discussions, with Shop 31 producing their standards within a day. “Both the lab and Shop 31 reps were eager and happy to help and prioritized the work to support the deploying unit,” said Morris. “They understood the need for urgency.”
Dixie Cox, Technology and Innovation Lab Subject Matter Expert for Additive Manufacturing, said the use of 3D printing proved an ideal medium for the request. “Additive manufacturing is well suited for rapid prototyping,” she said. “We managed to go through multiple iterations and improvements of a physical, tangible model in a matter of about two days. Another strength is the use of additive manufacturing in the customized sense. Code 266 requested one tool for exactly one intended use. Creating an in-depth procedure for the development of a custom-made tool can be impractical with traditional tooling methods. Turnaround times and wasted material can make such a request infeasible with subtractive manufacturing, so this is a victory as an effective and appropriate application of additive manufacturing.”
Jessica Roberts, NNSY Technology & Innovation Community of Practice Lead/Additive Manufacturing Lead, said, “it’s always exciting to have people visit the T&I Lab with an idea; this one in particular was a great example of a Real Idea [employee improvement suggestion] from beginning to end. The tool was the perfect size for quick 3D-printing, allowing several iterations to be printed and tested, despite the tight deadline. Code 266 remained engaged and enthusiastic throughout, providing details about the need, drawings of the system, design suggestions, and useful feedback on iterations. In the end, the tool had a positive impact on Code 266’s job, and we’re pleased to be part of this success.”
Shipyard Commander Captain Dianna Wolfson said, “This collaboration between Code 266, Shop 31 and our Technology and Innovation Lab is a great example of our shipyard’s One Mission—One Team mindset! Together as the Norfolk Naval Shipyard workforce, we are in the mission of providing exceptional, safe and timely delivery of warships back to the Fleet.”
For more information regarding innovation, contact the NNSY T&I Lab at 757-396-7180 or email the REAL Ideas program at [e-mail]. To learn more about the Additive Manufacturing Program, contact Roberts at [e-mail]

• Date Taken: 02.09.2021
• Date Posted: 02.09.2021 09:29
• Story ID: 388659
• Location: PORTSMOUTH, VIRGINIA, US