A ball float valve, also known as a float ball valve or simply a float valve, is a type of mechanical valve used to control the flow of liquids, typically water, in various applications. The valve operates on the principle of buoyancy and is commonly found in water tanks, cisterns, toilets, and other systems where liquid levels need to be controlled.

The main components of a ball float valve include:

Ball: A hollow, buoyant sphere typically made of plastic or metal. The ball is attached to a lever arm or a rod that opens or closes the valve.

Valve Seat: A sealing surface where the ball rests to close the valve and stop the flow of liquid when the ball is in the correct position.

Lever Arm or Rod: A mechanical linkage connected to the ball that transfers the buoyancy force to open or close the valve.

Inlet and Outlet: The connections through which the liquid flows into and out of the valve.

When the water level in a tank or cistern falls below a certain level, the ball float becomes less buoyant, causing the lever arm or rod to move downward. This movement opens the valve, allowing water to flow into the tank until the ball reaches the desired level, at which point the buoyancy of the ball closes the valve and stops the incoming flow.

Conversely, when the water level rises and the ball float becomes more buoyant, the valve opens again, allowing water to exit the tank until the ball reaches the required lower level. This cycle of opening and closing ensures that the liquid level is maintained within the desired range.

Ball float valves are simple and reliable devices commonly used in many applications because they do not require external power sources or complex control systems. They are particularly useful in situations where a consistent water level needs to be maintained, such as in water storage tanks and toilet cisterns.”