Control valve sizing

[AivarasD]

Hello,

I'm working at the factory as technologist/engineer. In this position i'm working couple month and faceing with some obscurities. I can't find right Kv value steam line for ON/OFF type angle seat valve. Tried to find information about that, but from different sources i get different answers. So i decided that best choise to talk with specialists and maybe they can help me. So I have couple questions. Does Kv value depends on valve type (angle seat valve, single seat valve or etc.? Does Kv value depends on controlling type (ON/OFF or with acuator). I'll be glad to get any information about valve sizing. Thanks in advance.

 

[RVAmeche]

Kv is (I believe) typically used in European products, while the North American equivalent is Cv. The equation to determine this parameter requires dP, SG, and flow rate.

The max Kv of the valve is determined by the valve geometry and valve type.

For your specific problem, you can look up the manufacturer catalog which should have that info. Otherwise you could look at comparable valves from a different manufacturer; that should give you a ballpark.

Here's a calculator for Cv to Kv

http://flowoffluids.com/calculators/k-cv-kv-conversion.aspx