Views: 62 Author: Site Editor Publish Time: 2019-08-20 Origin: Site
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. A range of materials and designs are available to handle different fluids and service conditions.
Duckbill Valve’s Material
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. Examples of Duckbill Valve material and their specifications can be seen as below.
1.FDA food grade & medical grade Duckbill Valve are OK for repeated use for compliance with Food and Drug Administration Regulations, and can work at -40℃ to 230℃, at elevated temperatures, the tensile, elongation, and abrasion resistance is far superior to that of most organic elastomers. Low temperature flexibility is another advantage silicone has over most organic rubbers.
2.LSR & Liquid Silicone Rubber Duckbill Valve: Unlike conventional rubber, LSR can withstand extreme temperatures without changing its properties, enabling high heat autoclave sterilization or use in very cold environments
3.Fluorosilicone & FVMQ Duckbill Valve have good resistance of oil and strong acid | alkali |oxidant, and also have common silicone advantage like working temperature: -40℃ ~ 230℃
4.EPDM Duckbill Valves have excellent performance at Ozone aging resistance, weather aging resistance & heat resistance.
5.Buna N & Nitrile Rubber Duckbill Valves performs excellently at oil resistance.
Duckbill Valve’s Structure and Working Principle
One end of the valve is stretched over the outlet of a supply line, conforming itself to the shape of the line, usually round. The other end, the duckbill, retains its natural flattened shape. When a fluid is pumped through the supply line and therefore the duckbill, the flattened end opens to permit the pressurized fluid to pass. When pressure is removed, however, the duckbill end returns to its flattened shape, preventing backflow.
Duckbill Valve’s Sealing Effect Mainly Depends on 3 Factors
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.