To provide a triple eccentric butterfly valve to solve such problems in conventional triple eccentric butterfly valves that it is difficult to control flow of fluid when a valve element is slightly opened, and that because fluid passing the valve element comes out in jet flow, a pressure reduced part is generated on the back of the valve element to cause pressure imbalance that leads to inconvenience such as vibration of the valve element.

To improve the valve element of this triple eccentric butterfly valve, in the valve element surface on the opposite side to the side where a valve shaft is provided, which conventionally has been formed flat, grooves that are almost perpendicular to the valve shaft extending direction are provided. The grooves are formed symmetric on both sides of the diameter of the valve element extended perpendicularly to the valve shaft as the center axis.

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