A butterfly valve is a type of quarter-turn valve used to regulate the flow of materials through a pipe. A butterfly valve consists of a disc that has a diameter equal to the inside of the pipe. This disc has a rod that passes through the center of the disc and is attached to an actuator on the outside of the valve. This actuator, operated from the outside of the valve, is what opens, closes, or can even throttle the flow inside the pipe. [
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