Designing a Nozzle on which a Vertical Vessel is mounted 3

[AK8824]

I have a Horizontal Vessel which has a 24" NPS nozzle, on top of this nozzle I have a 7.2 m tall vertical vesseal of Dia 610 mm.

To my understanding I should have the loads calculated for the vertical vessel (Wind and Seismic) and then apply these to the Horizontal Vessel.

Will someone from the group advise how to go about it?

Thanks.

 

[dgrande]

I would simply treat the flange on the vertical vessel as a base ring and calculate the loadings/reactions at the base ring from your Wind/Seismic/Weight loadings. Then I would apply these loadings into the 24" Nozzle via WRC107.

 

[TomBarsh]

You must consider two effects:

1- The local stresses in the shell supporting the vertical vessel (as dgrande has described).

2- The effect of the concentrated loads on the horizontal vessel when considered as a beam and on its supports. Thus you need to add a vertical load to the horizontal vessel at the location of the vertical vessel. This will add the effect of the weight of the riser to the horizontal vessel and saddles. COMPRESS will consider the mass associated with the vertical load when performing the seismic calculations. The one thing left unresolved is wind on the riser acting as base shear at the saddles. COMPRESS does not provide an option to apply a horizontal force to a vessel supported on saddles; I suggest increasing the effective diameter of the vessel so that the projected area of the horizontal vessel will account for the additional lateral force acting on the riser.


Tom Barsh
Codeware Technical Support