Axial Control Valve Sizing

[neroverdi41]

Hello

I need to make Axial Control Valve sizing for a line with a size of 16”.
Parameters:
P1=82-36 bar
P2=82-36 bar
Q=10000-100000 sm3/h
T=15 C

How can I size it? Also, why are two different pressure values given for inlet and outlet?
Can you help me urgently?

 

[neroverdi41]

It's flow velocity, not flow rate, but I just did a very simple calculation.

100000scmh (highest flow) is 27.7 smc/sec

Allowing for ideal gas, that turns into 0.77 actaul m3/sec (acms) at 36 bar
16" pipe internal area is approx 0.118 m2, so 1m is 0.118m3/m.

So velocity is 0.77 / 0.118 = 6.5m/sec. MAX. That's really very low for a gas flow velocity.

Min veleocity is going to be about 20 times less (10,000 scmh @ 82 bar, which is very very low.

Normally flow velocity inside a control valve is a lot higher than in the main pipe, so in your case my guess is you need something like a 10" or 8" control valve in order to get the range of CV you need.

at first I chose 10“ but due to the deadline we had a 12” valve ready. that's why I chose it. they want the speed especially low. then I thought I would lower the cv value with the cage design. that's why I asked about CFD in another topic.