Percent Elongation to Failure vs' Temperature

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Percent Elongation to Failure vs. Temperature
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Fracture Toughness vs. Temperature
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Critical Crack Length
Critical crack length (ac)required to cause
failure in a material fe edge effect
factor ?? hoop stress
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ASSEMBLY PROCEDURE 2
Temperature Plot at Highest Hoop Stress
Highest Hoop Stress
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Gage Locations on Hub
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Xray
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X-rays of the hub top view
Voids
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Voids
4 gross indications of shrinking/gas. Size and
nature are far in excess of Level 5. Severity of
indications is not acceptable to any industry
standards, military or civilian.
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Hoop stress during assembly procedures
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Von Mises stress during assembly procedures
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CONCLUSIONS

liquid nitrogen
Steels cooled below ductility transition
temperature Evaluate for brittle fracture from
fracture toughness
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CONCLUSIONS

• Cooling below dry ice temperature is not
  noteworthy. Clearance obtainable per unit
  temperature drop is not significant

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CONCLUSIONS

• Heating of outer components has remarkable
  benefits
• Larger diameters and radial hub thicknesses
  provide larger clearances
• Hubs shall be designed for optimal thermal
  performance
• Gradual cooling is preferred over sudden
  subcooling
• Specify and inspect toward tight geometric
  tolerances
• Perform nondestructive testing on all castings