existing hand-valves CV

[gelsi]

Hi,
when need modifications of existing systems, we must often estimate the CV of hand-valves (example 1/2" gate valve on nitrogen blancketing line).
Anyone can help me, i tried to find a table...
Tx

 

[Latexman]

Unless I have vendor data, I use the velocity head / K factor (not Kv) method for a wide open gate valve. I normally use K = 0.1 for a gate valve. K factor method You can use this and the appropriate equation and calculate a Cv. K to Cv

Good luck,
Latexman

To a ChE, the glass is always full - 1/2 air and 1/2 water.