A butterfly valve is a type of quarter-turn valve used to regulate or shut off the flow of fluids in a pipeline. It consists of a circular disc or butterfly that rotates on a shaft to control the flow. When the valve is fully open, the disc is parallel to the flow, allowing fluids to pass through with minimal resistance. When closed, the disc is perpendicular to the flow, blocking it. Butterfly valves are known for their compact design, lightweight construction, and ability to provide quick and efficient flow control. They are commonly used in applications such as water treatment, HVAC systems, and chemical processing, where space and weight constraints are a concern. Their design allows for a tight seal, making them effective for both throttling and shut-off applications