Custom Made Silicone Rubber Duckbill Valve Design Guide

Duckbill Valve, also known as Duckbill Check Valve, Duckbill Drain Valve, One Way Valve, which can be designed to provide the customer's required head loss and flow rate for particular applications, which valve designs take full advantage of one way check valve with duck shaped bills & lips in aim to allow air or fluid liquid forward flow and also prevent backflow. 

Duckbill Valve Sealing Effect Mainly depends on:

1. Depends on the die-cutting tool: It needs to be sharp enough, so that it can cut the silicone thoroughly to invoid diecutting burrs, and to invoid the situation of "slit" doesn't close well.

2. Depends on the permanent compression set value: for this dispensing valve, we use high-elastic FDA Food Grade silicone, so its restoring forces is good, the dispensing valve can close & open easily without the distortion situation.

3. Depends on the hardness: generally, dispensing valve with high durometer & hardness will have better restoring forces.

When Design Duckbill Valve, we should pay attention to:

1. For the Duckbill Valve slit cutting, there should be a flat surface on the slit cutting side as the followed picture shows, or the die-cutting tool & duckbill valve can not positionning.

2. And for the assembly of duckbill valve, it can be divided into 2 types:

A. For the pull-in type, we recommend to make a undercut inside for pull the valve and fix it with the device tightly as the picture shows:

B. For the stuck-in type, we suggest making a ring design as the followed picture shows:

What Material Do We use for Duckbill Valves?

Duckbill Valves can be made from a variety of materials. The material choice is based on the nature of the material handled, temperature, pressure, and frequency of operation. Elastomeric duckbill valve materials are highly resistant to chemicals at high temperatures. However, the mechanical properties of elastomeric materials will be weakened at a higher temperature (above 150°F). High pressure can also destroy the valve. Another factor that can affect the duckbill valve function is the concentration of the media it will handle. The material may exhibit satisfactory corrosion resistance to certain corrodents up to a specific concentration and/or temperature.

1. For FDA Medical Grade Duckbill Valves use in medical field, like for Manual Resuscitator & Respirator, Anesthesia Apparatus, Surgical equipment etc, we recommend to use FDA Medical Grade Wacker R401 material.

WAKER EL R401.pdf

Bio-compatible Certificate.pdf

MSDS-ELASTOSIL R 401_30 S.pdf

2. For FDA Food Grade Duckbill Check Valves use in food industry, we recommend to choose Wacker R2.

ENG-CENUSIL 2X0 (X=3,5,7) FDA TEST REPORT 201803- en.PDF

ENG-CENUSIL 2X0 (X=3,5,7) LFGB TEST REPORT 201803.PDF

ENG-2019CENUSIL 2X0 (X=3,5,7) LFGB TEST REPORT 2019-E.pdf

Notes: The Rubber Duckbill Valves can also be made from many other materials, like fluorosilicone, nitrile rubber, EPDM, etc. If you have special rquirements about the duckbill valve, feel free to contact us at sales@better-silicone.com, send us your 3D darwing at Stp or IGS format, and let us know your duckbill valves working environment, we'll recommend suitable material for you. ;）

How Do We Ensure the Duckbill Valves Quality?