A method and apparatus for controlling a flow of a fluid through a valve. In one illustrative embodiment, an apparatus comprises an elongate member, an actuation device, and a valve body. The actuation device is configured to move the elongate member, which may be associated with the actuation device, between an open position and a closed position. The valve body is configured for attachment to the actuation device such that the elongate member is positioned within the valve body. Fluid that flows into the valve body from a fluid source is allowed to flow out of the valve body when the elongate member is in the open position.