Question
When there is external pressure, the program calculates the reinforcement opening using the formula of AD B9 but there is no criteria for external pressure, this B9 is only for internal pressure, so there shouldn't be any calculation under external pressure of openings in AD2000.
Answer
AD 2000-Merkblatt B9 does not specify that it applies exclusively to internal pressure. Therefore, AutoPIPE Vessel performs calculations for both internal and external pressures accordingly.
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