Pipe Deflection using CAESAR

[mectub]

Hi everyone, i know that if i want to have the deflection number, i must use a node at interest point, but when i'm checking a model a maximum deflection is one of my goal, so is there a way in CAESAR to set a max deflection or max bending stress in order to get a warning?. What if i want to set max bending stress, let's say, 30% of allowable stress and get CAESAR to check this, is that possible?. Or i must check span by other means.

How do you all deal with max pipe deflection using CAESAR?
Another question if you allow me, where do i set CAESAR to use hot elastic modulus for calculations.

 

[BigInch]

There is no such thing as maximum pipe deflection. That is always relative to some other parameter, such as maximum pipe deflection for a given length between supports, etc.

 

[mectub]

You are right that is what I mean, there is a guide for piping supports used by my company establishing 15 mm max for pipe diam. <24", that is my max deflection. As well is included a top of 50% of basic allowable stress at operation temperature for bending stress limit.

 

[saplanti]

This is the pipe stress engineers work after the analysis. You can extract the deflections and stresses on spreadsheets and compare them in accordance with your criteria.
Do not expect everything from the software.

 

[vadersson]

Greetings mectub,

I have found the best way to check deflections is to export the Deflection data after analysis to a spreadsheet. Then I can run a Max and Min function in Excel to find the worst cases. I also use filters to identify which nodes are worst. It is pretty much a manual procedure.

You might be able to do something similar for Bending Stress, but I am not sure where you would get the data.

I am surprised by the 15 mm max deflection criteria. I was taught stress analysis with a 0.1 inch (2.54 mm) deflection criteria or occasionally 1/8" (3 mm) criteria. If you don't mind, what industry are you using the 15 mm criteria in?

Thanks,
Duncan

 

[mectub]

Oil and gas Industry (PDVSA Venezuela). I am referring to data at midpoint between supports.

 

[saplanti]

In the pipe stress model you need to create a node in the area of interest in case you want to get some details (deflection , stresses etc...) from the analysis output. If you did not have the node you cannot get anything. I suggest you to read the user's guide if this is not satisfactory.
This is the reason you need to be experienced on the modeling before involving with pipe stress analysis and at least you have the code with you to consult and get answers that you will have in mind if something goes different than you expected.