The present invention is a Ball Valves in which a valve chamber with an entrance and exit communicating with each other in a casing is formed, a Ball Valves with a circulation hole is provided in the valve chamber, an entrance-side ring valve seat is provided on the entrance side and an exit-side ring valve seat is provided on the exit side of the valve ball, the entrance and the exit are connected or disconnected by rotate-operating the BALL VALVES with a valve shaft hermetically passing through the casing, wherein a through hole passing through from a valve ball contact surface to a casing contact surface is formed in the exit-side ring valve seat, and a discharge orifice with one end communicating the through hole of the exit-side ring valve seat and the other end communicating ambient air is formed, and wherein a first passage hole which connects the circulation hole with the entrance in a first disconnection state where the valve ball disconnects the entrance from the exit, and which connects the circulation hole with the exit in a second disconnection state where the valve ball is rotated by 180 degrees from the first disconnection state so as to disconnect the entrance from the exit, and a second passage hole which connects the circulation hole with the through hole in the first disconnection state and which is disconnected from the through hole in the exit-side ring valve seat in the second disconnection state, are formed in the valve ball.

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