Hi all,

I am supposed to analyse AFC inlet and outlet piping integrally on one system. Per Equipment drawing Header is free to move in transvers dir'n and anchored in longitudinal dir'n at the front end of the tube bundle.

I have combined both system by anchoring at the center on the inlet and outlet nozzle with imposed displacement per configuration.

My Problem is that if i model the Inlet/Outlet connection by RIGID(WEIGHTLESS) option, loads are comming in Nozzle( 24 no's 6" nozzle)is exceeding API-661 allowable. But if i change those rigid option( 325mm both side from anchor point)to flexible pipe, load is comming within allowable.

My question: Using the flexibility of AFC Front header( modeled as pipe)
is justified ?
Thanks in advance for any guidence.