Abstract: A valve assembly includes a butterfly valve rotatably moveable between a closed position and an open position, and a shaft extending from the butterfly valve and rotatable about a longitudinal axis to move the butterfly valve between the open position and the closed position. The valve assembly further includes an actuator having a body operable to maintain an end portion of the shaft, the actuator operable to cause the shaft to rotate about the longitudinal axis, a housing sized to retain a portion of the shaft, the housing operable to be in removeable contact with the body, a seal intermediate the body and the shaft, the seal having an outer sealing surface contacting the body and an inner sealing surface contacting the shaft, and an anti-rotation interface between the seal and the housing.

Abstract: An exhaust gas recirculation valve assembly having a butterfly valve for selectively controlling the flow of exhaust gas includes a splined interface with an actuator, wherein the splined interface includes crowned splines. The crowned splines can be formed on a valve shaft of the butterfly valve, wherein an engaging sleeve includes a corresponding surface. The crowned splines accommodate variances in alignment between the valve shaft and the actuator, thereby improving an operating life of the valve assembly.

Abstract: Presented are a method, apparatus and valve assembly for preventing rotation. An exemplary valve assembly includes a butterfly valve rotatably moveable between a closed position and an open position, and a shaft extending from the butterfly valve and rotatable about a longitudinal axis to move the butterfly valve between the open position and the closed position. The valve assembly further includes an actuator having a body operable to maintain an end portion of the shaft, the actuator operable to cause the shaft to rotate about the longitudinal axis, a housing sized to retain a portion of the shaft, the housing operable to be in removeable contact with the body, a seal intermediate the body and the shaft, the seal having an outer sealing surface contacting the body and an inner sealing surface contacting the shaft, and an anti-rotation interface between the seal and the housing.