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Liquid Expansion

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lsuleigh

Chemical
Joined
Mar 6, 2006
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Location
US
Does anyone know a good site to find cubical exapansion coeffecients?? It would be really helpful to have a list of these values in per ºF for typical compounds.
Any help would be greatly appreciated.
 
Don't know of a "site" to direct you to but take a look in this thread...
thread124-133483
there's a number of other references that shouldn't be too hard to get.

Here's an updated link to the Chemical Processing article I mentioned in the referenced thread.

The Chemical Processing article also has a discussion about how to determine the cubical expansion coefficient for any chemical knowing the fluid density at the initial and final temperatures.
 
Thanks so much! I'll check it out!
 
lsuleigh,

If your scenario is ambient heating only, it is acceptable by established industry practice to NOT provide calculations and to install a small PSV. I have seen "small PSV" being a 1/2" to 1", with 3/4" being the most common. Therefore, IF your scenario is ambient heating only, what you are doing may be a waste of time.

Since you are new to this forum and you did not describe what you want the data for, I thought I'd add this. It may not apply. If it does not, sorry!

Good luck,
Latexman
 
Latexman,

Basically what you are saying is if you have a long transfer line where liquid can be blocked in, and is exposed to ambient/solar heat input, provide anywhere from a 1/2" to 1" TRV at the desired set pressure and you are good to go?
I assume since no calculations are required, this is not an ASME code device? I know the B 31.3 & 31.4 codes mention this type of releif device, but does not specify application criteria.

Thanks again
 
curve3104,

Yes, the required capacity will typically be very small for a pipeline within a plant, even a very large plant. My company has plants that are huge, world scale petrochemical plants (x miles by y miles big) and it's not a problem. Within a particular unit or block of the plant, relieving a few cc's drops the pressure like a rock. However, if your application is for a very long "cross-country" pipeline, you should evaluate it.

Good luck,
Latexman
 
Cubic expansion coef. can be calcualted by taking the difference in speciic volume at two different temperatures divided by the average specific volume, divided by the temperature spreade.

Beta = ((n2-n1)/navg)/(1/t2-1/t1)
where n (nu) equals specific volume or 1/density

Type in Assessing Thermal Relief Needs in google and this article will come up. I wrote the article.

 
Thank you so much for all the help!
 
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