Double Flap Valves, also known as Double Flap Valves or Double Flap Gates, are a type of airlock valve commonly used in industrial applications as a component in bulk material handling applications.

Double Dump Valves are primarily used to discharge chunky, pellets, granules or fibrous, bulk materials from hoppers, bins, and cyclones operating under positive or negative pressure.

Double dump valves are used to discharge a flow of material while at the same time serving as an airlock transition point to preserve the pressure differential above and below the valve.