MegaRule - Automated Shutoff Valves with Line Break Acuation

[mikeyridez]

Hi folks. just curious to see if anyone is using sophisticated software to determine pressure decay rates based on rupture between two sectionalization valves. So if a 16-inch pipeline (natural gas) was 5 miles long between valve stations, operating at 500 psig, is sophisticated software the only way to determine what the pressure decay would be if a rupture event occurs in the middle of the segment? Basically looking to validate set points for a line break actuation (non-remote controlled). thanks in advance.

 

[1503-44]

A slow leak is more difficult to detect than a line break.
Its a question of how accurate you need your answer to be.
Are you looking for a 1% drop in operating pressure, 5%, 25, 50%?
You can do some modeling in Excel using blowdown calculations.
Just a simple time stepped model of a segmented pipeline depressure with an assumed discharge rate , pressure drop, flowrate and velocity in each will take you somewhere.
Maybe you want to run a number of leak rate scenarios to get a range of possible results.
Now that I think about it, it would be interesting to compare some typical blowdown calculations with results from a full package simulator.


Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."