| Applies To | |
| Product(s): | AutoPIPE Vessel |
| Version(s): | ALL |
| Area: | General |
| Date Logged & Current Version | Dec 2023 44.00.01.014 |
Problem:
Why maximum test pressure of all component is not considered as vessel test pressure?
In the calculation of the Ptest, there is a value at 1.5614 MPA,
however in the AutoPIPE calculation, the software takes:
Why it doesn't take 1.5614 MPa.
Solution:
There is no issue in calculations. AutoPIPE Vessel calculates the test pressure correctly as per EN 13445-5 clause 10.2.3.3.1 (For Testing group 1,2 or 3)
Pt = MAX [ 1,43 Ps ; 1,25 Pd ( fa / fTd )min ]
For vessels where hydrostatic operating pressure > 3% of design pressure: Pt,mod = Pt + (Phyd,ope − Phyd,test ) with : Pt,mod ≥ Pt (This case falls under this clause)
Hydrostatic Test Pressure section gives calculated test pressure for all the individual components. And we have to consider the smallest test pressure of all component as vessel test pressure.
In this case we cannot test the complete vessel at maximum test pressure of Nozzle A (1.5614 MPa) because other components has less test pressure.
For Example (Nozzle A3):
Pressure Test (pt) = 1.3568MPa
Hydrostatic pressure in operation (Phyd,ope) = 0.0597MPa
Hydrostatic pressure in test (Phyd,test) = 0.0591MPa
Pt,mod = Pt + (Phyd,ope − Phyd,test )
Pt,mod = 1.3568+(0.0597-0.0591)
Pt,mod = 1.3574MPa