In technology, a device that controls the flow of a fluid. Inside a valve, a plug moves to widen or close the opening through which the fluid passes.
Common valves include the cone or needle valve, globe valve, and butterfly valve, all named after the shape of the plug. Specialized valves include the one-way valve, which permits fluid flow in one direction only, and the safety valve, which cuts off flow under certain conditions.
© RM 2009. Helicon Publishing is division of RM.