Duckbill Check Valve

Duckbill Check Valve is duckbill non-return valve, one-way check valve, performing a vital function to prevent backflow. Additionally, flow control check valve will open to allow the flow of fluid, liquid, water, air and gas as the opening or cracking pressure increased. Silicone rubber duckbill valves are widely used as seal or nozzle for breast pump, drain, medical device application.

Flanged Duckbill Check Valve

Sleeved Duckbill Valve

Duckbill Check Valve Failure Analysis & Solution

Why Choose Us? & Our Quality Control

Duckbill Check Valve Cutting Slit:

Burrs & Material Loss in Rubber Check Valve Slit: 

The problem generally caused by not enough sharp die-cutting tools. With blunt tool, the duckbill check valve slit is easy to have flashing in the slit and even make the slit into a gap, fully opened.

Operation staff operating techniques can also affect whether the slit can be cut well. Generally, the slit should be cut perfectly the first time. It will leave burrs if proceed second cutting.

Slit “Close” Problems for Non Return Valve: 

The burrs will lead to unclosed slit for one way control valve. 

The material restoring force will also affect the slit close.

Solution:

Using sharp die cutting tools & Proper positioning of rubber duckbill check valve in die cutting process.

Choosing high-elastic silicone rubber material so that the slits of one way check valve can open & close easily.

Rubber Check Valve Deformation:

Deformed rubber check valve cannot work. We can found that silicone mini duckbill check valve is easily to deform because of squeezing during transportation. The deformation is caused by improper packing.  

Solution: We will fill the small duckbill check valve packing with air to avoid the deformation during the transportation.

Duckbill Check Valve Design

• Structure Design: Flat surface needed in the one way duckbill check valve end so that it can be positioned and proceed die cutting. If sharp corner, it is easy to cut the slit inaccurately.

• Die-cutting tools design: Duckbill check valve will have a slit to prevent backflow and forward flow. The die-cutting tool will have angel 45-55 in the end to proceed the cutting process. The tool won't remove the material, just leave a “cut”.

• Cracking Pressure Design: Silicone rubber valve is one piece elastometic duckbill check valve. It is flexible and usually applied in low pressure environment. The material hardness and rebound resilience will affect the cracking pressure needed. Generally, the higher pressure application, the higher hardness material will be  chosen. 

Note: Duckbill check valves are available in various elastomer material, including medical and food-grade silicone, liquid silicone rubber (LSR) and hydrocarbon-resistant fluorosilicone rubber (FVMQ) to fit a broad range of media and temperatures. Also EPDM, Buna N & Nitrile Rubber, Neoprene / CR, Fluorocarbon rubber (FKM, FPM, Viton) can be chosen to make one way valve for every application.

What Need to Consider When Choosing Duckbill Check Valve?

Many factors must be considered to ensure the right choice of rubber duckbill check valve.

Flow Rate: The degree of opening on a duckbill check valve is determined by the flow rate. When flowing is higher than 8 feet per second, there will be a higher rate of abrasion. Duckbill valve life decreased as faster flow rate.

Inlet Pressure: Knowing the inlet pressure will help determining what type of check valve needed. Slip on check valve or flanged duckbill check valve. The selection depends on where the check valve will be located in device.

Back Pressure: Back pressure is the differential pressure between the inlet and outlet pressures. It created when there is upstream flow pressure in the system. Know how much back pressure the check valve need to withstand is important for your specified application.

Working environment & Application: Confirming the check valve materials compatible with the media passing through it via a material chemical compatibility guide is necessary. Additionally, if the valve is installed in a submerged condition, this means that there will always be back pressure on the valve.  In that case, a duckbill control valve designed for submerged conditions is needed. 

Duckbill Check Valve Installation

Flanged Duckbill Check Valve

Slip on / Sleeved Duckbill Check Valve

Duckbill Check Valve with Inner Undercut

Duckbill Check Valve with Outer Undercut

How Does A Duckbill Check Valve Work?   

Duckbill check valve are operated by a pressure differential. Above a certain upstream pressure, the valve will automatically open to allow flowing without requiring any other intervention. When pressure is removed, the duckbill end returns to its flattened shape, preventing backflow. 

Duckbill Check Valve Application

Medical Check Valve: Ventilator Check Valves, Respiratory Check Valve, One Way Breathing Valve are usually used as medical one way check valves for medical device and equipment like manual resuscitator & respirator, CPR mask, Anesthesia apparatus & surgical equipment.

Duckbill Valve for Breast Pump: Duckbill check valve also usually be used as a seal, air & liquid flow control check valves and nipple nozzles for Breast Pump by liquid silicone rubber injection molding LIM. like Ameda, medela duckbill valve, spectra duckbill valve etc,

Duckbill Drain Valve: Duckbill Check Nozzle is used as control valve in waste water system, drainage system, sewage pool drainage, and sewers drainage.  

Duckbill Check Valve Manufacturing Process

Duckbill Check Valve Liquid Silicone Rubber Injection Molding

As duckbill check valve manufacturer & supplier, we have

• Free Design support & Material suggestion for your application

• Prototype sample for your testing

• Mass Productiom: Compression molding or liquid silicone rubber (LSR) injection molding, slit die cutting

• Assembly & Packaging