Rocket Motor Component Additive Manufacturing Design

Project

Determine benefits of 3D printing Rocket Motor Attachment Ring.

• Determine performance of 3D printed material (Titanium)
• Consider time and weight savings vs current methods

Constraints/Requirements

• Overall mass below 18lbs
• Fit Northrop specified geometric envelope
• Withstand 4000 lbslug actuator design load
• Withstand vibration loads

Design Description

Performance Review

• The NASA Structures Manual provided equations for Hand Calculations to find stresses and loads due to loading.
• ANSYS simulation software was used to confirm hand calculations before testing.
• Northrop Grumman facilities were used to test the part in: flight loads, failure loads and intermediate loads.
• Predicted Failure Load: Between 35,000 –40,000 lb

Conclusion

• How well did the design meet the requirements?
  • Printed ring manufacture time was 4 months for section print. Full ring was unable to be printed.
  • Printed ring weight is 15lbs, (saved 3 lbs.)
  • Ring design met geometric envelope determined by Northrop Grumman.
  • Design test withstood lug actuator loads.
  • Actual Failure Load: Within 2% of predicted failure. Therefore, simulations and calculationsappear correct
• Lessons Learned
  • Add ribs or gussets instead of thickening lug ear design
  • Design to printer's capabilities
• Recommended Future Work
  • Print full ring design.
  • Static test fire
  • Flight test