With the same functions as the check valve, a double door flap valve releases water and prevents anything from flowing back into the pipeline under its gravity and the pressure difference between inside and outside the door. It is known for an excellent water control capability, high corrosion resistance, and easy installation.

Double door flap gates are an ideal choice for controlling wastewater in drainage pipes, culvert, and sewage treatment projects.

Specification
Different specifications of double door flap valves are available upon request

How it Works
The double door valve is able to release water out of the pipe and prevent liquid from flowing into the valve. It is comprised of upper and lower doors, which can close and open automatically under the buoyancy of water, as well as the pressure difference between the inside and outside of the door.

Advantages
1. The fluid control valve comes in a sealed cavity structure, with the weight proportion of the door ranging from 1.05 to 1.2
2. Counterweight is unnecessary
3. When the valve opens, the lower door opens first, then the upper. With a large open angle, the valve allows for less energy loss
4. Impact for the valve seat is reduced as the valve closes its upper door first when the valve closes

Installation Precautions
1. Before installing, weld the seat with embedded reinforcement and pour concrete on it
2. For optimum performance, operators can inject water into the valve's sealed cavity or release a certain amount of water from the valve to change the doors' weight proportion.
3. When installing several non-return valves at the same time, please ensure that each valve seat exactly matches each door.
4. Before installing the flap valve, please check whether the bolt connectors are loose during delivery and fix the loose parts
5. Ensure that the valve seat and the door are on the same plane
6. In case of door deformation, the valve seat and the door should be installed as a whole rather than being mounted separately.
7. Before pouring the concrete for the second time, find the right installation location, and then weld the bolts with embedded reinforcement.
8. A frame plate is mounted on the flap gate during the production to make sure the seat and door fit tightly. Therefore, remember to remove the frame plate from the drainage system so that the valve can open and close smoothly.
9. The mortar flowing into the seat, door, and baffle gap during the concrete pouring process should be removed completely to make sure the valve moves easily.

You may also find products like:
HDPE Non Return Valve, Two Flap Anti-Flood Valve, Heavy Duty Flap Gate, Stormwater Control Solution