Standard Air Knife™ – Hard hitting curtain of air for web, sheet and part blowoff.
What is the Standard Air Knife?
A quiet, energy efficient way to clean, dry or cool parts, webs or conveyors. The Standard Air Knife utilizes the coanda effect (wall attachment of a high velocity fluid) to create air motion in its surroundings. Using a small amount of compressed air as a power source, the Standard Air Knife pulls in large volumes of surrounding air to produce a high flow, high velocity curtain of air for blowoff.
Specials are available. Please contact us.
Why the Standard Air Knife?
Amplification ratios (entrained air to compressed air) of 30:1 are achieved with the Standard Air Knife, compared to 3:1 for drilled or slotted pipe. Air savings of 40% to 90% are possible when replacing these “homemade” blowoff devices. Pay-back is normally measured in weeks, not months or years.
The Standard Air Knife dramatically reduces “wind shear” by gradually introducing the entrained air to the ejected compressed air. Noise level is typically cut in half. The result is a high velocity, high volume sheet of air with reduced noise level and air consumption.
Drilled pipe or open jets, by contrast, provide minimal air amplification. They also produce unacceptably high noise levels as the compressed air shears into the still air.
How the Standard Air Knife works
Compressed air flows through the inlet (1) into a plenum chamber. It is then throttled through a thin nozzle (2) extending the length of the Standard Air Knife. This primary airstream adheres to the coanda profile (3), which turns it 90° and directs the flow down the face of the unit. The primary stream immediately begins to entrain surrounding air (4), for an amplification ratio of 30;1 at 6″ (152mm) away.
FAQ’s
- Air curtain made of aluminium with a plastic shim up to 82 °C
- Air curtain made of aluminium with a stainless steel shim up to 205 °C (custom built)
- Air curtain made of stainless steel with a stainless steel shim up to 427 °C*
- Air curtain made of PVDF with a PVDF shim up to 135 °C
*Temperatures above 427 °C can cause intracrystalline corrosion which obstructs the air gap.
Our Air Knives are engineered to provide a consistent and laminar airflow right from the start. If you observe any deviation from this, it may result in the accumulation of contaminants inside the Air Knife. In such cases, we recommend opening and cleaning the Air Knife as per the provided operating instructions.
For Air Knives exceeding a length of 18 inches, it is essential to supply compressed air through multiple input points, with up to 6 inputs required depending on the length, to ensure an even distribution of airflow. Additionally, please note that when dealing with the PVDF Air Knife, material characteristics can also impact the uniformity of the airflow.
Did you know that a single 3-mm hole consumes as much compressed air as a Super Air Knife model with a length of 152 mm (6″)? Additionally, an air knife offers a low noise level (below 70 dBA given an unobstructed blow-off path) and does not have a dead end (safety at work).
The amortisation period if you replace holes with optimised blow-off nozzles is less than 6 months.
To be able to answer this question, we need to investigate the specific use case. For example, the Super Air Knife could be operated with water to cool a workpiece or flush away loose residues. Experience shows that the water jet initially has a uniform outflow and then eddies further away from the air curtain. This means that use with water is possible.
If you need 360 ° wetting with water, we recommend our Super Air Wipe annular nozzle. The input pressure is up to 2 bar.
Of course, we also have legacy atomiser nozzles in various designs in our portfolio. They are suitable for cooling, washing, wetting, moistening, lubricating, etc.