Determining Valve Size for Natural Gas: V250 Rotary Ball Valve Calculation

[gillmitch92]

I am struggling with calculating the valve size from a V250 rotary ball valve by Fisher Controls International. The below table states that natural gas is running through the vavle and the following properties apply:Natural Gas

Required volumetric flow rate [@ STP] 2.8 x 106 litre per minute
Density [@ STP] 0.752 kg per m3
Specific heat ratio 1.31
Inlet pressure 20 bar gauge
Outlet pressure 6 bar gauge
Inlet Temperature 20 °C

Would I be right in thinking that I need to find the ratio between the required volumetric flow rate and the density of the valve first?

 

[Dr. Courtney]

http://www.forberg.com/pdf/techSup/Home_Tech%20Support_Valve%20Flow_calc_and_sizing.pdf

 

[gillmitch92]

http://www.forberg.com/pdf/techSup/Home_Tech%20Support_Valve%20Flow_calc_and_sizing.pdf

Thank you very much for the link - I'll take a look @ it.