What type of valve can transition from fully open to fully closed with a quarter turn?

The correct answer is a plug valve. A plug valve is designed to control the flow of fluid through a pipe and can transition between fully open and fully closed positions with just a quarter turn. This mechanism makes plug valves very efficient for on/off control as they allow for quick operation. They utilize a tapered or cylindrical plug that fits snugly inside the valve body and can be turned to align with the pipeline for flow or perpendicular to it for closure.

In contrast, gate valves require several turns of the handle to move the gate up and down, allowing for fluid flow or stopping it entirely. This makes them less suited for rapid operation compared to plug valves. Butterfly valves also provide a quarter turn operation; however, their design features a disc that rotates to permit or restrict flow, rather than using a plug mechanism. Check valves are designed to prevent backflow and involve a closing mechanism that reacts to flow direction, but they do not have a typical open/close function like plug valves.