Principle:

Duck bill valve by elastic neoprene and artificial fiber by special processing, shape similar to duck bill, it is called duck bill valve. Under the condition of no internal pressure, duck bill outlet is closed under the action of elasticity. As the internal pressure gradually increased, the outlet of the duck's beak gradually increased, maintaining the liquid to be discharged at a high flow rate.

Standard:

When the duck bill valve was first designed, in order to coordinate with the national standard, the flange standard of the duck bill valve with a diameter of less than 800 refers to the national standard 1.0mpa bolt hole center distance and flange outside diameter, and the pipe diameter above 800 (including) refers to the national standard 0.6mpa bolt hole center distance and flange outside diameter.

Function:

Rubber duck bill valve can prevent flood and sewage backflow into the street sewer and basement, avoid major losses, prevent water level rise, flood backflow into sewage treatment plants, drainage pump station; Prevent foul water or odourous fluid odour from spreading, and allow drainage at all times; In rainy seasons, it prevents city rivers from flooding the streets from sewers; The quality is better than the flap door, overcome the flap door such as lax closure and other defects.

Features:

1, 100% rubber structure, can meet all kinds of anti-corrosion requirements (according to the actual demand, can choose different rubber materials).

2. No clogging and good sealing.

3. Long service life, trouble-free and maintenance-free.

4, no moving parts and mechanical parts, no electrical signals and manual operation, no noise.

5, small opening pressure, more than 0.01 meters of the head can be opened.

6. Under normal conditions, head loss can be reduced to a minimum.

7. Can change various installation forms to meet customer needs.

8. Convenient installation, low cost and low operation cost.

Advantages:

Duck bill valve low cost, such as the use of appropriate rubber raw materials over the life of the metal check valve, easy to install, flexible installation, repair.

(1) maintain a high jet velocity.

(2) prevent seawater and sediment invasion is one of the main performance of the duck bill valve.

(3) it is beneficial to flush the discharge pipe.

(4) under certain conditions, higher dilution can be obtained.

(5) no corrosion.

Disadvantages:

The rubber body is not suitable for long-term outdoor work in the field.

(1) increase the project cost.

(2) increase the head loss of the diffuser.