How to calculate AutoPIPE's En13480 calculation for pressure extension stress seen in the Output Report?
"AutoPIPE’s code compliance calculations follow the equations provided by the code selected by the user. EN13480 sustained stress contains two terms: the Longitudinal pressure stress (LONG) and the moment stress. The (LONG) stress is calculated as PD/4t. The moment stress is determined as 0.75iM/Z. This can be seen in the default GR+MaxP, where MaxP is the (LONG) longitudinal pressure stress and GR is the moment stress.
For the P2 case, the user is taking the moment resultant of P2 and solving for this sustained stress, without (LONG), i.e. 0.0 + 0.75i*(0.0)/Z = 0MPa. The HOOP Combination is the same as the default MaxP hoop combination.
To create the case the user is looking for, I would recommend setting the P2 case to the hoop category with P2 as the only load case and set the factor to 0.3. This should give you 0.3*HOOP."
En13480 Piping calculations