What is the Cv value of a valve?
What is Cv value? The valve flow coefficient according to the JIS standard, represents the flow capacity in US gallons/minute of 60° F pure water when it is flowing through the valve with a pressure difference of 1 psi at the specified travel (operation range).
How do you calculate valve Cv?
Inlet Pressure 32 kgf / cm2 Convert to absolute pressure = 33.03 kgf / cm2 (A). Outlet Pressure 15 kgf / cm2 convert to absolute pressure = 16.03 kgf / cm2 (A). Because the fluid is a gas and ΔP ≥ P1 / 2 so we will use the formula. Cv = (48000 / (248 × 33.03)) x sqrt (0.86 x (273 240)).
What are the units of valve Cv?
In the U.S. system of units, the Cv coefficient is the number of U.S. gallons per minute of water that will pass through a given orifice area at a pressure drop of 1 PSI. An orifice or valve passage which has a Cv coefficient of 1.00 will pass 1 GPM of water (specific gravity 1.0) with a pressure drop of 1 PSI.
What is KV m3 h?
Kv is the flow coefficient in metric units. It is defined as the flow rate in cubic meters per hour [m3/h] of water at a temperature of 16 celsius with a pressure drop across the valve of 1 bar. At valves which discharge the flow directly into the environment it is used the non-dimensional Discharge Coefficient(C).
What is CV and KV in control valve?
The Valve Coefficient (Cv – in Imperial unit) – the number of US GALLON PER MINUTE of water at 60 °F that will flow through a valve at specific opening with a pressure drop of 1 psi across the valve. The flow factor (Kv – in Metric unit) – the amount of water that will flow in m3/hr.
Is KV same as CV?
The Relationship between Cv and Kv is Cv = 1.156 Kv OR Kv = 0.864 Cv.
What is a good CV percentage?
CVs of 5% or less generally give us a feeling of good method performance, whereas CVs of 10% and higher sound bad. However, you should look carefully at the mean value before judging a CV. At very low concentrations, the CV may be high and at high concentrations the CV may be low.
How do you calculate the CV of a valve?
How do you calculate CV for valves?
How do you calculate valve CV?
Control Valve Sizing.
How to calculate valve CV?
Cv = Valve flow coefficient. Q = Volumetric flow rate (SCFH – Standard Cubic Feet/Hour) P1 = Inlet Pressure (psia) P2 = Outlet Pressure (psia) T = Temperature (F) G = Specific Gravity of the gas. Calculate the minimum Cv value of your valve below. Choose a valve with a Cv value equal to or higher than the calculated value to achieve the
What is the formula for valve CV?
Flow Rate,given the Cv and ΔP