# What is the Cv value of a valve?

## 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 flow rate through a valve?
• How do you calculate differential pressure across a valve?
• How do you size a pressure control valve?
• What is differential pressure in valve?
• What are the three types of pressure?
• What is the maximum pressure handled by instrument valves?
• What is a DPCV valve?
• ## How do you calculate valve CV?

Control Valve Sizing.

• When sizing a control valve,the most common approach is to calculate the flow coefficient,Cv which is a measure of the capacity of the valve body and trim.
• C = Q/N1*√ (ρ1/ρ0)/(∆P)
• ρ1/ρ0 is the relative density.
• Fluid Density: 965.4 kg/m3.
• Flow Rate (Q): 360 m3/h.
• C = Q/N1*√ (ρ1/ρ0)/(∆P)
• 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

• Cv,given the Flow Rate and ΔP
• ΔP,given the Flow Rate and Cv