Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

High RhoV2 at relief valve discharge (not discharge piping)

Status
Not open for further replies.

Amas123

Petroleum
Apr 4, 2022
1
0
0
GB
Hi,

I have a balanced relief valve to verify in flarenet.

The valve is 4P6. The downstream piping is 10" to give a rhov2 less than 150,000kg/m/s2 and mach no < 0.75 in the downstream tailpipe.

The expander is flange to flange with the relief valve, but has sonic velocity at the inlet (/relief valve nozzle) and rhov2 > 200,000.

Backpressure is ok.

There are no AIV issues.

Is this typically acceptable? All guidance talks about downstream *piping*, not so much the conditions at the valve discharge itself. If there are no weak fittings and just straight pipe between the valve discharge and expander, is there actually a mechanism for failure? Considering the force at any restriction is proportional to rhov2*d2, but there is no 'd2' term for the fluid momentum to act against.
 
Replies continue below

Recommended for you

Status
Not open for further replies.
Back
Top