Ball valves are quarter-turn, straight-through valves that have a round closure element with matching rounded seats that permit uniform sealing stress. The valve gets its name from the ball that rotates to open and close the valve. Ball valves are used in situations where tight shut-off is required. They are wide duty valves, able to transfer gases, liquids and liquids with suspended solids (slurries).

Ball valves are commonly found in flowing systems on ships, fire safe protection services and chlorine manufacturers. They are not recommended for use in pharmaceutical, bioprocessing, or food and beverage applications because they cannot be cleaned easily. Exceptions can be made for chemical or non-sterile applications.