Dequn circular steel flap valve is a top-hinged automatic non-return gate for pipe outlets and wall discharges. It opens under outflow pressure and closes when external water tries to reverse into the pipeline—no hoist or electric power required.
Technical Specifications
| Product Name | Circular Steel Flap Valve for Pipe Outlets |
| Product Category | Flap valve / tide gate / non-return outlet gate |
| Shape | Circular flap with top hinge |
| Mounting | Flanged ring with bolt holes for pipe or wall fixing |
| Main Material | Steel (cast iron / FRP / stainless options on related models) |
| Operation | Automatic by water-level / pressure difference |
| Function | Allow drainage outflow and limit backflow / backflooding |
| Surface Protection | Industrial anti-corrosion coating |
| Typical Applications | Municipal drainage outlets, river bank discharges, pump-station outlets |
| Customization | DN size, material, hinge detail, coating system |
| Quotation Mode | Selected by diameter and site medium; price on request |
Core selling points
- No power needed: Opens and closes automatically with water differential.
- Backflow protection: Helps stop river or tidal water from entering drainage pipes.
- Flange mounting: Bolt-on installation to pipe ends or wall thimbles.
- Multiple diameters: Circular series covers common outlet sizes.
- Low daily O&M: No hoist operator for basic one-way control.
Who this product is for
Municipal drainage and irrigation outlet projects that need simple non-return protection at circular pipe ends.
Compatibility and accessories
- Matching flange / wall thimble
- Hinge pin and bushing spares
- Optional stainless upgrades for corrosive water
- Upstream screening where debris is heavy
FAQ
Q1: Does a flap valve need a hoist?
A: No. Standard flap valves operate automatically by water-level difference.
Q2: Steel or cast iron—which is better?
A: Depends on size, medium, and budget. Cast iron is common for many DN sizes; fabricated steel suits special diameters and reinforcement needs.
Q3: Can it seal 100% with zero leakage?
A: Treat sealing as a design/acceptance target under stated head. Debris and hinge wear affect field performance.
Q4: Is it suitable for seawater?
A: Use stainless or a higher-grade coating system when chlorides are high.
Q5: How do I choose the diameter?
A: Match the outlet pipe DN and confirm flange standard.
Q6: What maintenance is needed?
A: Keep the seating face clean; inspect hinge free movement after floods.
Q7: Do you supply square flap gates too?
A: Yes, square and other types can be quoted separately.
Q8: What to include in an RFQ?
A: DN size, medium, flange standard, quantity, and destination port.
How to inquire
Send pipe DN, medium, and destination to Export / International Sales. Tel: +86 13903193904.