Control valves control valve terminology bodies trim flow characteristics cv and kv sizing noise actuators and positioners. A conventional ball valve is normally not used as a throttling valve since a partial flow will create high velocity flow tear at the ball and the seal.
Ball valve floating type for reduce and full bore.
Ball valve cv curve. The full closure curve of a ball valve is then the above graph multiplied by the valve s flow coefficient or factor. V port ball valves flow rate cv. 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.
Product range flanged floating ball valves shell material class kitz product code bore 1 nominal design size body nps 1 2 3 4 111 4 11 2 221 2 345681012 page dn 15 20 25 32 40 50 65 80 100 125 150 200 250 300 carbon steel class 150150sctdz f split 14 class 150g 150sctdz f split 14 class 150150sctazm r uni 26. A 2 inch and 3 inch kimray back pressure regulator. C v calculator for valve sizing.
For full table rotate the screen. Typical flow coefficients c v for full bore valves. As a valve is opening the cv increases until the valve is fully open where it reaches its highest possible cv or 100 open cv.
Example of valve flow coefficient cv on the right we have a cv chart showing flow curves for two different valves. Cv kv fraction vs angle closure curve chart. This is used as a guide and is not a linear progression.
Cv value is an imperial measure of flow in us gallons per minute of water at 60 fahrenheit with a pressure drop of 1 psi across the valve. Cv vs angle closure curve values table. The valve flow coefficient c v is a convenient way to represent flow capacity of a valve across a range of fluids and process parameters the c v calculator will calculate either c v or flow using the supplied additional parameters of fluid inlet and outlet.
Into the control valve dialog box or a set of data can be generated using the control valve cv calculator by entering a single cv value at any valve position and selecting the type of valve and characteristic curve as shown in figure 2. This calculator can be used to help select a valve with enough flow capacity for a given application. Ball valve flow coefficients c v flow coefficients c v for typical ball valves reduced and full bore leakage classification of control valves seat leakage classification through control valves.
As the stem opens the cv increases. The below cv values are used to give an indication of flow rates for ball valves. This graph shows the cv or kv valve fraction vs opening and closing angle of a full bore ball valve.
Flow coefficient normally expressed as cv or kv depending on the countries.