Presently we are analyzing feedwater system and we have a question on modeling 3 way valve (3 way valve atached). We are not sure how to model this valve in the CAESAR pipe stress analysis.

Could you please give us a descriptive modeling thecnic how to model this valve in the analysis as soon as possible?.

Thake for you time.

Just model this as three rigid elements of the appropriate length. Assign the weight of the valve to each of these 3 elements in proportion to their size and length.

From the above discussion i want one clarification from Richard Ay .if we model three rigid element how to get the continuity of the piping.in caser when we go to rigid the valve is modeled... 123 please refer before performing the model.i may confuse.please rectify my confusion....

All three rigid elements are connected to the same node - that's your continuity.

thank you for your reply..

Hello;

I'm a new Caesar user.
I have a question about this 3way-valve.
If I wante to model a 3way-valve, I've to model it on 3 spreadsheets, right? The weight of this rigit elements is the total weight of the 3-way valve?

Thanks

Zeynep Degirmenci

Try and find out how CAESAR II handles rigid elements. After that u can do it urself.

CAESAR II does not understand 3 way valve, psv, control valve and so on...

Zeynep,


Yes, model it as 3 individual rigid elements, which means you use 3 spreadsheets. The combined weight defined on these 3 spreadsheets must add up to the total weight of the 3-way valve.

Samabdul,


True. A valve is a rigid element (because it is much stiffer than the pipe). A rigid element (from a numerical point of view) is a "3D beam element" whose stiffness is much larger than the "3D beam elements" used to model the connected piping. So from a finite element analysis point of view, it makes no difference whether the rigid is a control valve, a gate valve, a ball valve, a PSV, or a flange pair. So it's not that CAESAR II doesn't understand a valve - it is simply not necessary that it does.

Agreed! The intent was to say it is immaterial to recognise types!!

Off the topic a bit but 3 way valves in feed water can be really heavy. Make sure you have a support for it.

Thanks for your replies