How to model design pressure in the piping system?
How to model design pressure in the piping system?
(OP)
I have a problem like this. The piping operates at design temperature of 260 C and 150 psig. I am able to model the load from the temperature as a thermal load in 3-d framing model. I have a question what to do with design pressure of 150 psig? Should I model it as a strain load? I could likely transform the dsign pressure into longitudinal and circumferential pressure on the framing that represent pipes as linear elements.
Another point is in regard to the fact that system is open to atmosphere which means that pressure can not built due to oil heating. This is enabled by the sufficient discharge from pumps and the system of vents and overflows that connect expansion tank and sump tank as well as go directly to the atmosphere.
Another point is in regard to the fact that system is open to atmosphere which means that pressure can not built due to oil heating. This is enabled by the sufficient discharge from pumps and the system of vents and overflows that connect expansion tank and sump tank as well as go directly to the atmosphere.





RE: How to model design pressure in the piping system?
You have a longitudinal strain component due to internal pressure's hoop stress acting through poisson's ratio.
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"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/
RE: How to model design pressure in the piping system?
Why don't you use a commercial Pipe Stress analysis software to analyse the line or engage a Company that has this type of software. It's the easiest way to go!!
RE: How to model design pressure in the piping system?
DSB123 is correct.....
Piping systems are usually modelled using a commercial software package that allows the designer to qualify a system in accordance with a specific piping code.
In most packages, the software incorporates pressure stress as a primary stress and adds it to the deadload and other stresses. The software then compares this total stress to an allowable based on the Code selected.
One of the most used analysis software is CEASAR-II by COADE.
Other software packages exist.
-My opinion only
-MJC