Why use a duckbill valve?

DUCKBILL VALVES IN ACTION. Duckbill valves offer a wide range of benefits over standard valves in water and wastewater operations. We take a closer look at the compelling reasons to take advantage of the benefits duckbill valves provide.

Check valves are used in all stormwater and wastewater systems. They allow the forward flow of fluids before closing to prevent backflow conditions. These valves come in a variety of diameters and designs including swing, ball, diaphragm and duckbill check valves. They are simply designed, passive devices that rely on flow velocity and pressure to open and close without any manual or automated assistance.

For hundreds of years, towns, cities, farmers, and homeowners have been concerned with stopping rising rivers, ocean tides and even rainwater from infiltrating their premises in the event of reverse flow.

Millions of dollars are spent every year attempting to prevent back flows; and even more money is spent in reclamation and clean up after major floods, levy failures and ocean headwall damage.

For many years the accepted valve was the traditional style flap gate, which was always problematic from rusted hinges, warped disks, jammed open gates; to even the complete gate being removed by theft. Hence, the duckbill check valve was invented, and the rest is history.

The duckbill check valve is a flexible sleeve shaped like a duck’s beak. It allows forward flow of water with positive head differential pressure which progressively opens the valve as flow increases. Duckbill check valves consistently provide the tightest seal for preventing backflow. The flexible elastomer material can compress tightly around trapped solids if necessary. Its ability to resist ocean waves, freezing temperatures and scorching heat makes the valve one of the most specified valves on the planet.

The duckbill valve can be designed and engineered to provide minimal back pressures for low lying areas to very high back pressures in hi tide or flooding conditions as well as hi back pressures related to water hammer or valve slam.

The Proco Style 711/731 ProFlex™ check valves are engineered for installation on pre-existing pipelines such as manholes, outfalls and vaults where the outfall invert of the pipe is close to the floor of the manhole or outfall. When a new installation is being designed, the 711/731 valves can be engineered into the pipe layout with little concern for outfall clearance due to its “low slope” design.

The new Style 711/731 check valves allow the valves to be installed without any costly and labour-intensive changes to the existing structure. The 711/731 is engineered to crack open at 1-2” of head pressure, and with its unique engineered sloping bottom, the valve ensures zero potential for standing water. With its all-elastomer design, the valve can be installed without concern of seizing or rusting which can cause premature failure and maintenance issues. An expected life for these valves is 35-50 years.

The ProFlex™ 711/731 valves are covered under US Patent No. 11,221,081 which ensures a protected valve for both Proco and our customers.

Fluid Control Sales & Installations is the Australian agent for Proco’s range of valves and other products. For more information head to www.fluidcontrol.com.au