How to size valves using the KV value
January 29, 2021
Thanks to their versatility, ball valves are widely used in both domestic and industrial plumbing.
The variations of this type of shut-off valve also include 3-way valves for fluid mixing or deviation.
Imagine, for example, a system where different fluids have to be managed in a way that guarantees their correct dosage, correct mixing, and their movement through the piping at different moments. In all these cases the solution is to install a three-way valve which, as the name suggests, can connect three different ports and regulate the flow of the liquids according to the position of the interception organ, namely the ball.
How a three-way valve works
In order to understand how a three-way valve works, it is essential to observe how the ball permits the passage of fluid.
Valve operation depends on the rotation of the ball that is positioned in the centre of the valve. The ball has a cylindrical cavity, which does not just open and close the valve, but also partialises the flow of the liquid being transported. The ball, in fact, can direct the flow in an L-shaped or a T-shaped pattern. The T flow pattern is ideal for mixing fluids or as a bypass, while the L configuration is recommended for flow deviation.
The T configuration has four flow paths: double, to the left, to the right and the cutoff position, while the L configuration has three, namely left, right and the cutoff position.
The strong points of Mondeo three-way valves
We have selected a line of stainless steel 3-way valves that are more efficient and practical for the final user thanks to the combination of quality materials and special design features.
The 316 stainless steel used to produce the body and the ball makes these valves particularly suitable for industrial use, in particular with aggressive liquids, or in harsh environments, for example those characterised by high levels of salinity.
Another important aspect is the diameter of the passage, designed to reduce flow resistance, and as such to optimise the hydraulic efficiency of the valve.
Finally, the low torque of the actuator shaft notably reduces the opening and closing stress, which means savings in the choice of the actuator for motorised 3-way valves.
Three-way valves with actuator
With manual 3-way valves it is the operator who activates the mechanism. When the valve is motorised, it is activated automatically. More specifically, if the actuator is pneumatic, the compressed air acts as an energy carrier that triggers ball rotation.
The advantages of fitting an actuator on a 3-way valve are evident. Automation becomes fundamental if a notable force is required for activation, or if the valve is located in points that are difficult to reach, but even when fast opening and closing are required because of emergencies.
Mondeo 3-way valves are already set for motorisation because equipped with a direct coupling base for the actuator.
We can also supply valves with a pre-fitted pneumatic actuator. With this solution we can guarantee a perfectly integrated valve-actuator system, thanks to the choice of actuators that are not just reliable but also sized to adapt perfectly to specific requirements and keep costs down.
