Rangeability of Control Valve
C ontrol Valve What is Valve Rangeability ? Rangeability is the ratio of maximum controllable flow to minimum controllable flow For the control valve selection rangeability is one of the important selection factor. Minimum and Maximum Cv of Valves are calculated .If the ratio of Cv Maximum to Cv Minimum is within the rangeability of the selected control valve ,the valve should function properly Cv - Flow Coefficient Rangeability of Control Valve Rangeability of a control valve is defined as the ratio of maximum to minimum flow that can be acted upon by a control valve after receiving a signal from a controller. Today’s control valve applications often require a degree of high rangeability, i.e. require a valve to control a flow from small to large flow. The rangeability of any control valve is affected by mainly three factors: Valve Geometry – Valve geometry (i.e. the geometry of the closure element and seat) has an inherent rangeability due to the design and configuration ...