Dear Habib,

I agree with your general explanation but I asked you.....

1)Have you ever evaluated nozzle for WNC load case.If yes then please through some light.

2)It is senseless to evaluate nozzle for WNC load case.

3)It does make a sense to evaluate nozzle in sustained load case.

4)WNC load cases as mensioned earliear are used for civil structure design.

5)WNC+H(Hanger stiffness set to rigid) used for Nozzle Alignment Check.

6)In case of top-top pump of large sizes (suction or dischage)the spring sizing is done by considering zero density in the vertical leg.The reasoning is that the weight of the liquid in vertical leg will be supported by pump impellar and not by the pump nozzle flange.Therefor it all depends on the good engineering judgement employed to size and design the system.

Regards,
Aslam