Description: The ball valve is basically a ported sphere in a housing. Rotation of the sphere by 90° changes the position from open to closed. The ball may be of fixed or floating design and full or reduced port. Ball valves are available in a variety of sizes and with a wide choice of actuating mechanisms.

Usage: Ball valves are used in a wide range of application including flow control, pressure control and shutoff. They can be designed for use of corrosive fluids, cryogenic liquids, very viscous fluids and slurries, in addition to normal liquids and gases. They can be used at high pressures and temperatures.

Advantages: Ball valves generally have a very low pressure drop and low leakage. They are small in size and low in weight compared to other types of similar ratings. They are rapid opening and are relatively insensitive to contamination.

Disadvantages: The seat of ball valves are subject to extrusion if the valve is used for throttling. Fluid trapped in the ball in the closed position may cause problems if the ball is not vented. Because of quick opening, they may cause water hammer in the system or cause surge pressure which may be undesirable.