V-Port ball valves are a type of control valve that is designed with a v-shaped port or bore in the ball, as opposed to the traditional full-bore or reduced-bore designs. This unique v-port configuration allows for more precise control over the flow of fluid through the valve.
The v-shaped port in the ball is a key distinguishing feature. The vertex angle of the v-shape varies but typically ranges from 15 to 90°.
The shape of the port provides a linear flow characteristic, meaning that the relationship between the valve opening and flow rate is more predictable and controllable compared to other types of valves such as butterfly valves and full port ball valves.
V-Port ball valves are often used in applications where precise control and modulation of flow are critical, such as in process control systems. As such, they are typically actuated using pneumatic, electric or hydraulic actuators. In each case, the actuator should be a "positioning" type of actuator (as opposed to a simple on/off actuator). They offer excellent rangeability, in some cases >200 with repeatable flow characteristics. Positioning actuators use control and feedback signals to throttle the valve. For electric actuators this is usually done via a 4-20mA signal. Pneumatic actuators utilize an electro-pneumatic positioner that converts an electronic input signal (ie: 4-20mA) into a corresponding air pressure output signal.
V-Port ball valves are available in a variety of materials, including stainless steel, carbon steel, and alloys, to suit different applications and corrosive environments. Their construction is similar to other ball valves, with a rotating ball that controls the flow through the valve body.
Valworx v-port valves are all 3-piece construction which allows the ball to be easily changed if needed.
Higher quality v-port balls are machined from solid cast stainless steel blanks, allowing the valve to withstand the same pressure rating as full port valves. Cheaper options include plated balls and v-port screens. The latter cost considerably less but are severely limited in performance.
Valworx v-port balls are machined from solid 316 stainless steel.
V-Port ball valves have some drawbacks, however. First, flow is reduced vs full port valves. For narrow vertex angles (ie: 15°) this flow restriction may be greater than 70%. Use of v-port valves will therefore often require larger pipe sizes. Second, v-port valves may also be more susceptible to clogging and should only be used with free-flowing, non-particulate media. Third, in high-velocity applications v-port valves might be more susceptible to erosion which could impact the long-term durability of the valve as well as the flow characteristics.
In summary, v-port ball valves are specialized control valves designed for applications requiring precise flow control. Their unique v-shaped port configuration makes them suitable for industries where accurate modulation of flow rates is critical for process optimization and efficiency.
