Duck bill check valve is a type of back pressure control valve

Duck bill check valve is a type of back pressure control valve which is shaped like a duck bill. This valve is used to protect the environment by preventing water from flooding or causing damage. It is easy to install and can be used either by slipping over the end of the pipe, or by mating with a flange and fasteners.

The rubber used on these valves offers continual corrosion resistance, meaning that no matter what type of fluid you are dealing with the rubber will not be affected. Neoprene rubber also protects against Ozone sunlight, as well as stopping barnacle growth and sea weed build up.

These valves can be designed to operate in a few millimeters of water up to several hundred kPa. This pressure drop across the valve is one of their main differences to other types of check valves, as this reduces the possibility of water hammer occurring.

It is important to choose the correct duck bill check valve for your application, which needs to consider factors such as the risk of water hammer, the expected flow rate, and the financial impact of installing a valve with a high safety margin. This will ensure the valve provides a safe, reliable solution that is appropriate for the intended purpose.

Choosing the right material to be used for the valve is also an important factor to consider when selecting a duck bill check valve. It is usually best to use a food grade silicone or rubber material, as this will provide the best sealing performance and longevity.

The hardness and rebound resilience of the material is also an important consideration, as these will affect the cracking pressure required to open and close the duck bill check valve. Generally, higher hardness and rebound resilience materials will have better restoring force when the slit is closed again.

In addition to this, the size of the slit and lip should be chosen carefully, as this will determine the ease of opening the duck bill check valve under certain pressure. Similarly, the structure of the valve should be chosen carefully, as this will determine how easy it is to position and die cut the duck bill check valve.

When installing a rubber duck bill check valve, the pipe that it will be fitted to must be cleaned and free of debris and sharp edges. Once this is complete, the duck bill check valve can be installed.

There are many different types of duck bill check valve to choose from, each with its own unique features. These include curved bill ended, straight bill ended, and slip on valves.

Curved bill ended duckbill check valves offer 50% more sealing area compared to straight bill ended duckbill check valves, and require a slightly higher cracking pressure to open than the straight bill ended model. This makes them more suitable for applications where there may be a lot of debris present that will effect sealing performance.