Nozzle Flex for Top nozzle of vertical vessel

Posted by: SpMangak

Nozzle Flex for Top nozzle of vertical vessel - 10/08/18 12:23 AM

Hello Sirs,

I got method to reduce the actual nozzle loads on equipment. It was to input Stiffnesses on Custom of Nozzle Flex menu, and Stiffness values have found on output of Nozzle Pro for vessel calculation. But this equipment is vertical vessel, and it is to reduce nozzle loads of Top nozzle what i want. But it has not being proceeded output running since vessel direction and nozzle direction are same. I am not finding any method for this matter.
Could anyone help the this matter?
Posted by: Michael_Fletcher

Re: Nozzle Flex for Top nozzle of vertical vessel - 10/08/18 07:59 AM

The "vessel orientation" changes meaning for heads and nozzles versus cylinders and nozzles.

"Vessel orientation" now means which orientation is the 0 degree mark for locating nozzles in cylindrical coordinates.

I.E. look at the vessel drawing, find the 0 degree reference orientation, and input that value, which will generally be +/-X or +/-Z, but could be anywhere in between. The nozzle angle from 0 will reference this orientation.
Posted by: Dave Diehl

Re: Nozzle Flex for Top nozzle of vertical vessel - 10/08/18 08:00 AM

As you have learned, the custom nozzle stiffness input works only for those vessel/nozzle combinations that define a plane. Your vertical (top) nozzle on a vertical vessel does not define such a plane so in-plane and out-plane are not defined.
I suggest you revert to the older style of input - use a set of springs each using a Node/CNode pair. A set of 6 restraints will do it.
I have requested a program change where the "custom" nozzle definition will also accept global input (X, Y, Z) rather than just local input (a vessel reference vector).
Posted by: Michael_Fletcher

Re: Nozzle Flex for Top nozzle of vertical vessel - 10/10/18 10:56 AM

As a point of clarification, my statements above are for Nozzle Pro input, not CAESAR.
Posted by: danb

Re: Nozzle Flex for Top nozzle of vertical vessel - 12/09/18 09:40 PM

Only for stiffness. you may want to consider that is as per a cylinder perpendicular on your nozzle, with a radius double as for your vessel diameter (the ellipse has a radius double than the vessel radius). However this is will be in your responsibility. Other choice is Nozzle Pro.