Herr Ohliger,

It looks as if you are mixing loads from different solutions or "states" of the piping system - for example, mixing loads from the operating+wind state and the operating-wind state - in order to develop a maximum stress level.

I do not agree. The calculated stresses must caused by a consistent load set - stress is calculated from the Fx,y,z & Mx,y,z that occur together - all from a single "state" of the piping system.

Please provide additional description if I misunderstand your point.