Many times we receive a call from a customer looking for an Air Knife but they are unsure which design is the best to suit their needs. With 3 options to choose from, the Super Air Knife, Standard Air Knife and Full-Flow, it can seem like a somewhat daunting task so lets take a look at some of the key differences between the units. We keep all of these models in stock and can ship same day on orders we receive by 3 pm.
Let’s start with our most popular choice, the Super Air Knife. The Super Air Knife is our most efficient unit, using a 40:1 amplification rate of entrained surrounding air to compressed air, it consumes only 2.9 SCFM per inch @ 80 PSIG while maintaining a low sound level of 69 dbA. This unit produces a laminar airflow across the entire length of the knife and there are air inlets on each end, as well as on the bottom. We offer lengths from 3″ up to 108″ in aluminum, 303ss, or 316ss. Additionally we offer lengths up to 54″ in PVDF (Polyvinylidene Flouride) for applications requiring superior chemical resistance, like those associated to acids, solvents or aggressive chemicals. There are 1/4-20 tapped holes on the bottom of the knife which can be used for mounting. We recommend the Super Air Knife most often because it uses the least amount of compressed air and has the most even airflow from end to end.
Secondly we offer our Standard Air Knife which provides a 30:1 amplification rate, consuming slightly more compressed air at 3.4 SCFM per inch @ 80 PSIG. These units are louder at 83 dBA and feature air inlets on each end. Lengths available from 3″ up to 48″ in aluminum or 303ss construction. The airflow length is 1″ smaller than the length of the knife (1/2″ of no flow on each end), for example a 12″ Standard Air Knife has a 13″ physical length with a 12″ airflow length. This is the first knife we ever manufactured and is a solid choice with good performance.
Lastly, the Full-Flow Air Knife. Again providing a 30:1 ratio of entrained ambient air to compressed air, has the smallest dimensional footprint. Air consumption is slightly less than the Standard Air Knife at 3.1 SCFM per inch @ 80 PSIG with an airflow length equal to the length of the knife. We offer lengths from 3″ up to 36″, again in aluminum and 303ss and the air inlets are on the back of these units. The Full Flow Air Knife fills the need for customers with limited mounting space and who cannot fit a Super Air Knife into the desired location.
Hopefully this information will help in making the best decision to fit your needs. Of course if you still need additional support, please don’t hesitate to contact one of our Application Engineers for assistance.