I am a freshman in using Flarenet. I have some question regarding the rated flow calculation.
Does anyone have any idea how Flarenet calculates the rated flow? Why is it affected when calculation method and valve type is changed?
According to API RP 520, the rated flow of the relief valve maybe calculated by taking the ratio of the calculated orifice area and standard orifice area against the calculated flow. However, in Flarenet, the calculated value is different from the value using the API method. For example:
Item: PRV-1515
No. of PRV: 1
Set Pressure: 10.4 barG
MABP: 5.0 barg
Accumulation: 110%
Relieving temperature: 80 deg-C
MW: 18.99
Governing Case: CV Failure
Calculated Relieving Rate: 51, 577
Calculated Area: 6834 mm2
Selected Orifice Size: 6Q8
Selected Area: 7125 mm2
Keeping the information shown above, the rated flow calculated (auto mode) by changing the method and valve type were as follows :
Peng Robinson-Peng Robinson
Balanced Type = 36,026.6 kg/h
Pilot Type = 52,556.4 kg/h
SRK-SRK
Balanced Type = 37,920.4 kg/h
Pilot Type = 52,409.6 kg/h
Compress. – Ideal Gas
Balanced Type = 37,945.4 kg/h
Pilot Type = 52,444.2 kg/h
Thanks in advance!