Cast Iron Flap Gate

Cast iron flap gate is a type of check valve installed at the end of drainage pipelines to prevent backflow of external water. Its core structure consists of four parts: valve seat, valve plate, sealing ring, and hinge, suitable for both circular and square outlets.
Structure and Working Principle
The cast iron flap gate operates automatically based on the pressure difference inside and outside the pipeline: it opens for discharge when the internal water pressure exceeds the external pressure and closes automatically when the external water level is higher than the pipeline level. This design requires no manual operation and is highly energy-efficient.
Materials and Types
Materials: Traditionally made of cast iron, stainless steel, or structural steel, there is now a gradual shift toward composite materials (such as fiberglass reinforced plastic and high-density polyethylene).
Types: Includes floating box type, flat plate type, sleeve type, hanging type, single/double door type, and energy-saving type, suitable for various media including water, sewage, and seawater.