Ball Valve Function

Ball valve is best used for fast-acting stop/start applications. They are considered quick-acting because they only require a 90° turn of the handle to operate the valve. The quarter turn minimizes ball valve operation time and decreases the possibility of leakage due to wear.

Ball valve can be used for throttling service if a high level of accuracy is not required. Throttling causes the partially exposed seat to erode because of the high velocity flow and pressure. The wear will eventually lead to ball valve leakage. Leakage can be corrected if the manual ball valve is automated and is able to move faster in response to a changing position signal.

The closure element of a ball valve consists of a ball shaped disc. The ball valve is opened by a quarter turn of the actuator. The turn lines the hole in the ball parallel to the flow so the media is able to pass through the valve. When the valve is closed the ball is rotated so the hole is perpendicular to the flow, blocking the media.

Ball valve is very efficient with gas and liquid media. This type of ball valve can be used for challenging chemicals such as dry chlorine, hydrofluoric acid or hydrochloric acid, and oxygen. Slurry transport is not highly recommended because the slurry tends to solidify in the cavities around the ball and seats. This increases the operating torque and may break the ball valve. Most manufacturers recommend not exceeding 3% trace solids in the media.