A butterfly valve is a flow control device used to regulate the movement of fluid through a pipeline. It derives its name from the wing-shaped disc that rotates on a shaft inside the valve body to open or close the flow passage.

Butterfly valves are versatile and widely used in various industries such as water treatment, HVAC systems, chemical processing, food and beverage, and oil and gas. They are especially suitable for applications that require quick operation and minimal pressure drop.