The ball valve is a very simple valve that is controlled manually or through automated processes. It is a quarter turn valve, which means opening and closing of the valve requires only a 90-degree turn, making it fast and easy to operate even in small or confined spaces.
Ball valves use a hollow ball with a hole drilled across the ball to control the flow as off or on. When the handle connected to the ball is turned to the open position, the holes line up with the inlet and outlet ports of the valve, allowing for full flow through the valve. When turned 90 degrees, the holes do not line up with the ports, immediately stopping all flow.
While typically used for on and off control only, they can also be used to roughly control the flow by a less than a full turn of the control lever. However, this is a very crude level of control and not the intention of the primary use of the valve.
Materials to Consider
The specific design of the valve and the use dictates the best material for the valve body and the actual ball. The most common options are metal, ceramic and metal combination and the PVC ball valve design.
The PVC ball valve offers several advantages over other materials. The use of polyvinyl chloride as the ball valve body means the valve is non-reactive and non-corrosive, ensuring it has a long duty cycle even if only rarely used. This prevents rust and corrosion from damaging the interior of the valve and preventing full sealing when required.
Additionally, a PVC ball valve is much lighter than either the metal or metal and ceramic options. Lighter valves are a better match for PVC and light plastic tubing, eliminating the need to provide additional support or mounting for the valve in equipment.