Moog Gas Evacuation Systems Design Review

1. Moog Gas EvacuationSystems Design Review Austin Frazer Eileen Kobal Ana Maria Maldonado Marie Rohrbaugh

2. The Team • Austin Frazer • Role: Lead Engineer - Analysis • Major: Mechanical Engineering • Eileen Kobal • Role: Lead Engineer – Mixtures of Gas Fluids • Major: Chemical Engineering • Ana Maria Maldonado • Role: Team Manager • Major: Industrial Engineering • Marie Rohrbaugh • Role: Project Manager • Major: Mechanical Engineering

4. UUT Problem Statement Fixtures interface between AGT can and UUT Fixturing/leakage similar to other side UUT leakage Fixture leakage To mass spectrometer High pressure helium High pressure helium Leakage from Unit Under Test Leakage from Fixture Leakage from room through lid and baseplate

5. Current Procedure Oring Leakage Diagram Our process needs to minimize leakage from fixtures

7. Voice of the Engineer

8. Design Constraints • Safety • Contamination • Class 10,000 clean room. • All products should comply to a strict cleanliness certification • Existing Fixture • Cannot modify inside of can • Must be attachable to can

9. Resources • Gas Flow • Nitrogen gas at 120psia available • Vacuum at 1psia available • Hardware (possibly) • People • Moog professionals • Guides • Professors • Budget • 7,500 per system

10. Function Tree

11. Concept Generation

12. Pugh Diagram- Move/ Evacuate the Gas

13. Pugh Diagram- Access the Gas

14. Block Diagram

15. AN Fitting Flexline to Vacuum Source 2-way 2-position solonoid valve To vent Relief Valve To large o-ring X2 Flexline to Nitrogen Source

16. AN Fitting Flexline to Vacuum Source 2-way 2-position solonoid valve To vent Relief Valve 3-way 2-position solonoid valve To large o-ring X2 Flexline to Nitrogen Source

17. Analysis Performed – Simscape Model

18. Orifices 1 and 2: Model Oring Leakage. Required: Cd(Oring), A(Oring) Simscape Free Body Diagram 3000 psi 0 psi (To Mass Spectrometer) Entire Vent Volume Flow Sensor Pressure Sensor Orifice 3 : Accurately simulate sflow out of vent. Required: Cd(vent), A(vent) Case 1) 14.7 psi (baseline) Case 2) 0 psi (Vacuum) Case 3) Variable pressure/vacuum (nitrogen)

19. Analysis Performed – Simscape Model • Case 1)

20. Analysis Performed – Simscape Model • Case 2)

21. 2 1 Analysis Performed – Simscape Parameters • Model Orings as Orifices • L = Approximate leak rate of the seal, std. cc/sec. • F = Permeability rate of the gas through the elastomer at the anticipated temperature, std. cc cm/cm2 sec bar. (example: Butyl's permeability at 77oF with Acetylene is 1.26 x 10-8 std. cc cm/cm2 sec bar) • D = Inside diameter of the O-ring, inches. • P = Pressure differential across the seal, lb/in2 . • Q = Factor depending on the percent compression and whether the O-ring is lubricated or dry (from figure 3 below) • S = Percent compression on the O-ring cross section expressed as a decimal (i.e. for 20% compression, S = 0.20)

22. Diffusion Diffusion Coefficient for 2 gasses Diffusion Flux: Movement due to Diffusion across an area

23. Gantt Diagram

24. Risk Assessment

25. Questions??