Ball valve has a spherical plug. The spherical plug is a controlling element. They are widely used in chemical process industries. It is used where throttling and shut off combination is required. It offers good flow characteristics. Ball valve consists of a two-way globe and the ball rotates between resilient seats. It is compact and requires low maintenance and no lubrication. It is available in venture pattern, reduced and full port patterns. By giving a quarter turn to the ball, the valve can be closed or opened. The valve does not give good throttling. It can be available in size from 6mm to as large as 900mm. It can be used for pressures up to 500 kg/cm and temperature up to 300°C.