A valve is provided that includes a valve housing, a valve element, and a
flapper. The valve housing has a passage. The valve element is
rotationally mounted in the passage and moveable between an open position
and a closed position. Additionally, the valve element has a flow channel
extending therethrough. The flapper is coupled to the valve element and
moveable between a closed position, to thereby substantially seal the
flow channel, and an open position, to thereby unseal the flow channel,
the flapper configured to move to the open position when a differential
pressure across the flapper reaches a predetermined value.