graphic design header

 

 Technical    Flow Coefficients 

 

Valve Flow Coefficients


Definitions and conversion factors for the three valve flow coefficients Kv, Cv and Qn.


1. What is the Kv Value?

2. What is the Cv Value?

3. What is the Qn Value?

4. Converting between Kv, Cv & Qn


1. What is the Kv Value

Kv value is the metric measure for the flow of a valve. It is defined as:

The volume flow in cubic metres per hour of water at a temperature of between 5° and 40° Celsius with a pressure drop across the valve of 1 bar.


2. What is the Cv Value?

Cv is the imperial measure for the flow of a valve. It is defined as:

The volume flow in US gallons per minute of water at a temperature of 60° Fahrenheit with a pressure drop across the valve of 1 psi.


3. What is the Qn Value?

Qn value is used in pneumatics to define the flow of a valve. It is defined as:

The volume flow in litres per minute of air at a temperature of 20° Celsius, with an input pressure of 6 bar and a pressure drop across the valve of 1 bar.


4. Converting between Kv, Cv & Qn

Kv = 0.86 x Cv
Kv = Qn / 1078

Cv = Kv / 0.86
Cv = Qn x 0.0008

Qn = Kv x 1078
Qn = Cv / 0.0008
We can locate and identify most solenoid valves or you can search our database of manufacturers part numbers or by basic description port size function material etc with our valve wizard here (next to cart top right). Our technical data sheets show all flow Kv and Cv flow coefficients, port sizes, connection type, pressure range, sealing, voltage and protection levels to help users and engineers.
 
Solenoid Valves phone
Solenoid Valves 12v ATEX high pressure Solenoid valves uk Design Solenoid Valves brass plastic stainless steel