cryogenic bending/bowing of LNG rundown lines

jim0210,
Please explain for us how you have a "horizontal pipe lines are partially filled" By partially filled you mean part liquid (LNG) and part vapor (NG). How is this possible?
PennPiper

An example of Partial filling situation may be an initial LNG filling in to the pipe line (e.g. start up) or an LNG draining out from the pipe line.

Thanks,

jim0210

Most facilities allow for expansion and contraction of Vacuum Jacketed Piping, utilizing bellows and pressure relief valves at key points in the system. Seek qualified solutions from liquid nitrogen Vacuum Jacketed Piping manufactures.



Best regards
pennpoint

If I understood your question correctly, assuming the pipe is half filled, you're dealing with differential stresses between the top half and bottom half of your horizontal runs along the pipe due to the temperature gradient from top to bottom of the pipe cross section.
Besides selecting the right material for your pipe, if you're trying to come up with analytical solutions to the stresses developed across the section, the only way to go is by Finite Element Analysis method or a FEA software. "FEPIPE" is one that is costumized for pipe stress analysis. A software like "CAESAR II" won't help you here, because it considers the pipe as beam elements and performs the stress calcs based on beam equations. Or you can go with an all purpose FEA software like "ANSYS". I guess it depends which one is easier for you to get a hold of.
good luck

drno

Gentlemen,

L.C. Peng wrote this papaer and it may be useful to this discussion:


Regards, John.

Thank you gentlemen for your valuable replies. And also Thank you John for this valuable article by LC Peng it is very usefull.

Thanks again

jim0210