A valve assembly includes a valve body and an opening extending through the valve body along a longitudinal axis. The valve assembly also includes a valve member arranged within the opening, the valve member being movable, along the longitudinal axis, between an open position and a closed position. The valve assembly includes an upper seal positioned to seal against at least a first portion of the valve body. The valve assembly includes a lower seal positioned to seal against at least a second portion of the valve body, wherein both the upper seal and the lower seal travel with the valve member as the valve member moves between the open position and a closed position.