What valve coefficient means?

The valve flow coefficient (Cv) is a number which represents a valve’s ability to pass flow. The bigger the Cv, the more flow a valve can pass with a given pressure drop. A Cv of 1 means a valve will pass 1 gallon per minute (gpm) of 60oF water with a pressure drop (∆p) of 1 (PSI) across the valve.

How do you find the coefficient of a valve?

The volume flow rate for liquids can be calculated by multiplying the fluid velocity times the flow area. Thus, Cv is numerically equal to the number of U.S. gallons of water at 60°F that will flow through the valve in one minute when the pressure differential across the valve is one pound per square inch.

What is valve recovery coefficient?

The valve recovery coefficient is a dimensionless, numerical factor that represents a valve’s flow vs. liquid pressure curve, and thus the valve’s tendency to cavitate. If this factor is higher than desired, cavitation might develop.

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.

What is Cv in a control valve?

Valve Flow Coefficient (Cv) is the flow capability of a control valve at fully open conditions relative to the pressure drop across the valve. It is defined as the volume of water (GPM in the US) at 60°F that will flow through a fully open valve with a pressure differential of 1 psi across the valve.

What is Cv in air?

Valve Flow Coefficient (Cv) is a valve’s capacity for a liquid or gas to flow through it. It is technically defined as “the volume of water at 60°F (in US gallons) that will flow through a valve per minute with a pressure drop of 1 psi across the valve.”

What is Cv in valve design?

What is Cv in air flow?

What is the function of valve packing?

The purpose of valve packing is to prevent leakage. In a typical valve, the gland follower is tightened until there is no leakage. The valve is then test-operated to make sure that the packing is not compressed so tightly that the valve does not turn easily.

What is valve style modifier?

Valve style modifier (Fd): A valve capacity factor. The default value is 1. Cv (or Kv) Column: The valve flow coefficients at each of the given valve positions. FL Column: The liquid pressure recovery factor.

Is KV same as Cv?

Kv is the flow coefficient in metric units. Cv is the flow coefficient in imperial units. It is defined as the flow rate in US Gallons per minute [gpm] of water at a temperature of 60 fahrenheit with a pressure drop across the valve of 1 psi.

What is Cv in solenoid valve?

Rating the valve capacity in terms that relate to all operating conditions is done by determining the flow factor (Cv) of the valve. The Cv value is the number of U.S. gallons of 60°F water per minute that, when flowing through the valve, causes a pressure drop of 1 psi.

How do you calculate the CV of a valve?

For example a valve with a Cv of 10 will flow 10 GPM with a 1 psi pressure drop. The formula used to select the valve Cv with the specified differential pressure is: Cv=GPM/ ( (SQ RT (∆P)). If the specified ∆P is 4 psid and full flow is 10 GPM the calculated CV is 10/SQ RT of 4 = 5.

How do you calculate flow through a valve?

The flow across the aortic valve is calculated by taking the cardiac output (measured in liters per minute) and dividing it by the heart rate (to give output per cardiac cycle) and then dividing it by the systolic ejection period measured in seconds per beat (to give flow per ventricular contraction).

What are the types of valve?

Because of the diversity of the types of systems, fluids, and environments in which valves must operate, a vast array of valve types have been developed. Examples of the common types are the ball valve, butterfly valve, globe valve, gate valve, plug valve, diaphragm valve, reducing valve, needle vave, check valve and safety/relief valve.

What is the equation for flow coefficient?

The valve allowing fluid through it is more efficient than the one which faces problems with the flow process. The formula used to calculate the flow coefficient is: C v = Q x (SG/DeltaP) 1/2 . Where Q= rate of flow. C v = Flow capacity or flow coefficient.