| Applies To | |
| Product(s): | AutoPIPE |
| Version(s): | ALL |
| Area: | calculations |
| Date Logged & Current Version | January 2024 23.00.01.367 |
Problem:
Thermal Expansion values shown in AutoPIPE is not matching with design code B31.8 (2010), Why?
Material : Carbon Steel
Operating temperature : 400F
Ambient temperature : 40F
The Auto calculation option of AutoPIPE shows 2.912 inch/100ft.
Based on ASME B31.8, Table 832.2-1, it is a 2.93 inch/100ft.
Why it is not matching?
Solution:
Check the reference of Thermal expansion data from Help<Contents<Libraries<Standard Pipe Materials<B318-10.LIB Standard Materials,
Here you can see Thermal Expansion values for B31.8 (2010) is taken from B31.3 Code (Table C-1).
ASME B31.8 code gives very generic thermal expansion values and hence AutoPIPE considers these values from ASME B31.3 code.
Data As per B31.3 Code, Table C-1 :
Thermal Expansion at 40F : -0.212 in/100ft
Thermal Expansion at 400F : 2.70 in/100ft
Hence value of thermal expansion 2.912 in/100ft is correct (0.212+2.70= 2.912 in/100ft).
See Also
"Press/Temp/PipeID" - Input grid tab