B 31.3 is an ASME code for Process piping, Multiple time we come across situation, where we need to calculate the design pressure for a pipe.


In such cases, ASME VIII-Div-1 seems helpless, and B 31-3 comes for rescue.


Clause 304.1.2 talks about Straight pipe under internal pressure,




P > Internal design pressure

D > Outside diameter of pipe

S > Stress value of material as per table A-1

E > Quality factor from Table A-1A & -1B

Y > Coefficient from table 304.1.1


Compare equation 3a with ASME VIII-1 Formula (UG-27)

The formula is completely same, except factor PY against 0.6 P!

Y factor varies from material & Temperature, which varies from 0.4 to 0.7


As I’m working on one of the project, where I’m manually doing calculation, I thought this will be fastest way to share!


Keep reading!



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