Cv Value For Ball Valve

※2 calculation of viscosity correction is necessary when the fluid is liquid and the kinematic viscosity is 20 mpa・s or more and the calculated cv value is 0.01 or less.

Cv value for ball valve. Has been contributed to offer high quality product to the global market. Online calculator to quickly determine valve and orifice cv & kvs values for air. The use of this flow coefficient (c v) calculator leads to a standard calculation to compare valve capacities.

Butterfly valve cv values vary with the disc angle and valve size. As the stem opens, the cv increases. A lot of the valve manufacturers quote flow coefficient cv for us gal/min for psi at 60degrees.

The below cv values are used to give an indication of flow rates for ball valves. Gallons per minute of water at 60°f that will flow through a control valve at a specified opening when a pressure differential of 1psi. In industry the popular terms for full port is full bore.

First question is k dimensionless and the same value for calculations in us gallons/minte and litres/min. We recommend you select a valve for which the cv falls between 20% and 80% open stem travel. Both values are found in the cv charts supplied on the following pages.

Cv [gpm] [psi] nps (inches) dn (mm)full bore: Equations displayed for easy reference. It is used to determine the appropriate sizing of the valve as well as evaluating the flow kinetic energy in regards with process and piping integrity.

Q is the rate of flow (expressed in us gallons per minute), Select a valve which offers calculated cv for the minimum and maximum flow between 20% to 80% of port opening. Therefore, the main differences between different flow coefficients come from the type of valve, and of course the opening position of the valve.