# ASME PTC 2010 - Intergraph Smart Instrumentation - 13.1 - Reference - Hexagon PPM

## Integraph Smart Instrumentation Sizing Equations

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English (United States)
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Intergraph Smart Instrumentation
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Reference
Smart Instrumentation Version
13.1
1. Calculate mounting factor:

*L [m] • Other connection types: 2. Calculate Reynolds number: 3. Calculate Strouhal number: 4. Calculate natural frequency:

*L [m], B[m,] E[Pag]

1. Calculate average outside diameter:

• Tapered thermowell: • Other thermowells: 1. Calculate approximate natural frequency: 2. Calculate correction factor Hf

• Tapered and straight thermowell: • Stepped thermowell: 1. Calculate correction factor Haf: 2. Calculate correction factor Has: 3. Calculate natural frequency with ideal support: 4. Calculate natural frequency of the mounted thermowell: 5. Calculate Vortex shedding frequency

*B[m] 6. Calculate Scruton number:

*B[m] 7. Calculate miscellaneous parameters:

*B[m], L[m], E[Pag

1. Parameter Gsp

• Tapered and straight thermowell: • Stepped thermowell 1. Parameter Grd (for stepped thermowell only): 2. Stress concentration factor: • Other connections: 1. Stress concentration factor at support plane (for stepped thermowell only): 2. Temperature de-rating factor: 8. Calculate Frequency Limit

• Low density gases: Nsc >2.5 and Tr ,100000 • General case: Other values of Nsc and Re 9. Compliance with the frequency limit requirement:

1. Initial evaluation of compliance:

• The thermowell is in compliance with the frequency limit requirement if; Go to step 10.

• The thermowell is non-compliant with the frequency limit requirement if; Go to step 10.

1. Evaluate compliance with cyclic stress limit for general case:

• Calculate velocity for in-line resonance:

1. 2. 3. 1. Calculate cyclic drag stress at the root: 2. Calculate combined drag and lift stresses: 3. Calculate fatigue stress limit: 4. Compliance with cyclic stress limit:

• Tapered and straight thermowell:

• Not compliant with the cyclic stress limit and frequency limit if; Go to step 10.

• Complies with the cyclic stress limit if; Set new frequency limit: Go to step 9g

• Stepped thermowell:

• Not compliant with the cyclic stress limit and frequency limit if; Go to step 10.

• Case Calculate: • Not compliant with the cyclic stress limit and frequency limit if; Go to step 10.

• Complies with the cyclic stress limit if; Set new frequency limit: Go to step 9-g.

1. Re-evaluate compliance with the frequency limit requirement if cyclic stress is acceptable:

• The thermowell is in compliance with the frequency limit requirement if; • The thermowell is in non-compliant with the frequency limit requirement if; 10. Compliance with the static stress limit requirement:

*B[m], P[Pag], S[Pag]

1. Calculate radial, tangential, and axial stress due to external pressure: 2. Calculate steady-state drag stress at the root: 3. Calculate steady-state stress due to the drag force: 4. Calculate maximum stress: 5. Calculate left-hand side of the Von Mises criteria: 6. Calculate right-hand side of the Von Mises criteria: Compliance

• Tapered and straight thermowell:

• Not compiled with the static stress limit if; • Complies with the static limit if; • Stepped thermowell:

• Not compiled with the static stress limit if; • Case Calculate: • Not compliant with the static stress limit if; • Complies with the static stress limit if; 11. Compliance with the Dynamic Stress Limit requirement

Calculate parameters: 12. Calculate drag and lift stresses at the root: 13. Calculate combined drag and lift stresses: 14. Calculate fatigue stress limit: Compliance

• Tapered and straight thermowell

• Not compliant with the dynamic stress limit if; • Complies with the dynamic stress limit if; • Stepped thermowell

• Not compliant with the dynamic stress limit if; Go to Compliance with the Hydrostatic Pressure Limit requirement section in this topic

• • Calculate: • Not compliant with the dynamic stress limit if; • Complies with the dynamic stress limit if; 15. Compliance with the Hydrostatic Pressure Limit requirement

*B[m], P[Pag], S[Pag]

16. Calculate pressure rating for the shank: 17. Calculate external pressure rating for the tip: 18. Calculate pressure rating of the thermowell: 19. Compliance

• Not compliant with the hydrostatic pressure limit if; • Compliant with hydrostatic pressure limit if; 