3 way valve

Posted by: 123

3 way valve - 09/04/07 10:05 AM

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.
Posted by: Richard Ay

Re: 3 way valve - 09/04/07 10:07 AM

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.
Posted by: pktmurugan

Re: 3 way valve - 10/16/07 05:04 AM

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....
Posted by: Richard Ay

Re: 3 way valve - 10/16/07 06:45 AM

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

Re: 3 way valve - 10/16/07 11:17 PM

thank you for your reply..
Posted by: Zeynep

Re: 3 way valve - 11/05/07 02:48 PM

Originally Posted By: Richard Ay
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.


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
Posted by: SAMAbdul

Re: 3 way valve - 11/05/07 08:49 PM

Try and find out how C2 handles rigid elements. After that u can do it urself.

C2 does not understand 3 way valve, psv, control valve and so on...
Posted by: Richard Ay

Re: 3 way valve - 11/05/07 10:26 PM

Zeynep,
Quote:
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?


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


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 c2 doesn't understand a valve - it is simply not necessary that it does.
Posted by: SAMAbdul

Re: 3 way valve - 11/06/07 12:07 AM

Agreed! The intent was to say it is immaterial to recognise types!!
Posted by: Jouko

Re: 3 way valve - 11/06/07 01:21 AM

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

Re: 3 way valve - 11/06/07 12:54 PM

Thanks for your replies