Threaded Pin-Lock Retaining Ring

Mechanical and Fluid Systems
Threaded Pin-Lock Retaining Ring (MSC-TOPS-152)
Locking threaded fastener allows granular torque preload adjustment
Overview
Innovators at NASA Johnson Space Center have developed a locking threaded retaining ring that comprises a novel pin-lock mechanism allowing granular preload adjustment with no interference to desired torque values. The pin-lock mechanism may be adapted to other COTS threaded fasteners, thanks to a novel pinlock mechanism method configured for different applications. NASA’s Threaded Pin-Lock Retaining Ring System was originally developed for applications aboard the Lunar Terrain Vehicle Ground Test Unit, or LTV-GTU (shown above), as a need existed to better withstand the demands of space travel, namely vibrational resistance. A more compact fastener solution is presented that is lighter, allows more precise control for the attachment loading force, and can be redundantly locked in place by both the thread design and mechanical pin(s) to prevent loosening. This technology may have numerous applications in those that require axial preload. The Threaded Pin-Lock Retaining Ring has a technology readiness level (TRL) 6 (System/sub-system model or prototype demonstration in an operational environment), and is now available for patent licensing. Please note that NASA does not manufacture products itself for commercial sale.

The Technology
Bolt fasteners can be used to provide control of the attachment force but they are not typically viewed as providing a locking attachment unless they are torqued to a prescribed percentage of the yield strength of the bolt. Adhesives are often used as an alternative means of locking threaded bolts, but adhesives are not well suited to inspection, removal or replacement, nor are they well suited for use in the space environment. Enter the Threaded Pin-Lock Retaining Ring system. It comprises a retaining ring, a structural component, the component being retained, and the pin-lock mechanism. The threaded interfaces allow for components being retained to be clamped between the retaining ring and the structural component. The pin-lock mechanism may be designed specifically for a given application and can be applied to both male and female threaded applications. The Threaded Pin-Lock Retaining Ring is configured for applications having precision torque requirements, and could be applied to any system with axially rotating components such as those commonly found in aerospace, automotive, cycling, energy sector, imaging, manufacturing, maritime, and robotics industries.
Lunar Terrain Vehicle Ground Test Unit (LTV-GTU)
Benefits
  • Comprises redundant locking system
  • Allows granular torque preload adjustment
  • Pin-lock architecture may be adaptable to other fastener types
  • Employs novel formulas to dictate design applications

Applications
  • Aerospace
  • Automotive
  • Cycling
  • Energy sector
  • Imaging
  • Manufacturing
  • Maritime
  • Robotics
  • Any system with axially rotating components could be considered.
Technology Details

Mechanical and Fluid Systems
MSC-TOPS-152
MSC-27822-1
Patent Pending
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