Nozzle Stiffness

Posted by: Gimini55

Nozzle Stiffness - 10/11/05 12:21 PM

Hi all,

Modeling a piping system up to a flanged-nozzle requires us to plug-in stiffness including rotational and I have in the past posted this subject which had led me as well to study FEA despite there are FE Pipe-Nozzle Pro (we have but I can't use myself). Since the pipe is flanged-connected to a nozzle via a number of bolts, am I not really dealing with the stiffness of the bolt rather than the stiffness of the nozzle?. Or, the bolts are always designed to be much more stiffer than the nozzle? Thanks.
Posted by: Edward Klein

Re: Nozzle Stiffness - 10/12/05 02:19 PM

While there are limits to the bending that a flange connection can take, I've typically treated them as rigid.

Now, if you have access to Nozzle Pro, getting nozzle stiffness values is easier than falling out of bed. You pretty much just have to fill out the basic dimensional information on the main screen, fill in the pressure on the screen that comes up from the LOADS button. Then run it.

I typically use uncorroded wall thickness for the shell and nozzle when checking for stiffness values for Caesar. I'll then use the corroded wall thickness values when checking the forces/moments that Caesar gives me to validate the nozzle stresses.