Control Valve Cv Si Units. It describes the relationship between the pressure drop across an orifice valve or other assembly and the corresponding flow rate. Si and metric cv flow coefficients si (international standard) cv flow coefficients are the number of liters per minute of water which will pass through a given orifice or passage at a pressure drop of 1 bar.
It is defined as the flow rate in us gallons per minute [gpm] of water at a temperature of 60º fahrenheit with a pressure drop across the valve of 1 psi. Flow coefficient information scope ——the values given below are applicable to floating ball valve/tru nnion mounted ball valve, when the ball valve is in full open condition. Units by dividing it by 54.9.
Flow coefficient, cv, and flow factor, kv, are values used to specify the hydraulic capacity of a control valve.
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. Cv for fluids cv for liquids is the volume of 68°f water in u.s. For a specific control valve, flow coefficient cv/kv is determined experimentally by control valve manufacturers, and you can found it in manufacturers technical specifications. Flow coefficient k v ——volumetric flow rate of water at a.
