Cue up your favorite version of Auld Lang Syne as we say goodbye to 2022. As another year draws to a close, we start to take stock of all the happenings in the past year. The beautiful moments and high points are important to remember, but also take a moment to appreciate the trials and tribulations you’ve overcome and how they’ve molded us into stronger versions of ourselves.
With that said, EXAIR would like to extend a big thank you to all the colleagues, customers, readers, friends and family that help make this company what it is today. Thank you for choosing EXAIR and partnering with us in 2022. We look forward to continuing give you our best in 2023.
EXAIR will be closed December 30th and January 2nd. We will return Tuesday, January 3rd.
So you went and got yourself a Super Air Knife and now you need to mount it, and start “cutting”. There are a few things we need to review in order to get these installed and functioning correctly. First, let’s take a moment and make sure that your compressed air system has enough air to run this Super Air Knife at its optimal level. Number 1-9 of the top 10 reasons these do not work are linked to the customers lack of air to the Super Air Knife. Step one of this process is to make sure that you have a pressure gauge at the point of use of your Super Air Knife. Knowing that your plant runs 120 psig throughout the system is not a measurement, there are many things that can inhibit this performance from point A to the point of use… Engineering best practices are to have a pressure gauge at each point of use.
Next, we need to make sure your compressor is large enough. At 80 psig, you will need 2.9 SCFM per INCH of Super Air Knife (see table below). 3rd grade math tells us that a 36″ Super Air Knife will need 104.4 SCFM to run efficiently at 80 psig. When given the correct amount of air, this should feel as if you are driving down the road at 50 MPH and you put your hand out the window. This 50 MPH example is true for any length of air knife, at 80 psig, as long as there is enough SCFM. If your Super Air Knife does not feel this way, it is not getting the air it needs…
Back to the 104.4 SCFM. A general rule of thumb is that 1 HP give us @4 SCFM. So in this example, you will need at least a 27 HP compressor to run this 36″ Super Air Knife, and ONLY this Super Air Knife. When sizing EXAIR products, we have to look at the air pressure, and the air volume. One will not work without the other.
Now as we look at this 27 HP (108 SCFM) of compressed air coming to this 36″ Super Air Knife, we need to address how it is getting to the Super Air Knife. How far away from the air compressor is it? Even though the inlet size on the Super Air Knife is 1/4″ NPT, the line from the compressor needs to be big enough to bring the right amount of air to the Super Air Knife. Right off the bat, I can see that any line smaller than a 3/4″ will not work, regardless of how close it is to the compressor. I can also see that this 3/4″ line will only work if the Super Air Knife is 20′ or less away from the compressor. When you bump the line size to 1″, this will allow you to be up to 100′ away. If you have questions on your line sizes, please feel free to ask us to help.
So now that we are confident you have the right amount of air at the point of use, we are ready to mount this bad boy. Obviously we want to look at the angles and positioning, and something we call counter flow. We generally want the air from the Super Air Knife stay in contact with the surface it is cleaning (blowing, cooling, warming, coating, covering etc…) for the maximum amount of time possible. To accomplish this, we need counter flow as seen in the picture to the right. Basically the air is blowing in the opposite direction that the belt is moving.
The last part to discuss here is the physical practicalities of mounting the Super Air Knife. One option is our handy dandy Universal Air Knife Mounting kit seen here to the left. These are a perfect solution for easy and quick installation. You can simply adjust the angles and tighten. You can eventually add thread lock, or something similar for permanent installation. You may need more than one. We recommend one for Air Knives up to 23″, for those 24″-54″ Air Knives we recommend two, 55″-71″ = three, 72″-95″ = four and 96″-108″ = five of these.
This is not the only way to mount these. There are size 1/4″-20 screws every 2 inches in the Super Air Knives. You can simply remove these screws, and attach any type of brace, or mounting bracket to these holes. If our screws are not long enough to fit your bracket, these are pretty easily found locally.
The Super Air Knives is an amazing tool. It can assist in many ways. If you would like to discuss more about these, or any other EXAIR product, please reach out.
Thank you for stopping by,
Brian Wages
Application Engineer
EXAIR Corporation Visit us on the Web Follow me on Twitter
Whenever air gets compressed, it reduces the space for the water molecules to remain as a vapor; which causes condensation. For this, compressed air dryers are an important part of a compressed air system. They are designed to remove moisture to prevent condensation further downstream in the system. The three main types of dryers are refrigerated, desiccant, and membrane. For this blog, I will cover the refrigerant-type compressed air dryers.
Compressed air dryers are rated with a dew point rating. A dew point is the temperature at which the air has a relative humidity of 100%. Since the air cannot become more saturated with water than 100%RH, water will condense and fall out like “rain”. You can see this effect during the cool mornings when dew forms on the grass. Compressed air dryers are designed to reduce the dew point temperature of your compressed air. For a refrigerant type, they are near the dew point temperature of 38oF (3oC). Like a refrigerator, they use refrigerant to cool the compressed air. We cannot go below this temperature as it could form ice inside the dryer. But, as long as the ambient temperature does not go below 38oF (3oC), liquid water will not be present in the pneumatic system.
There are two main types of refrigerated air dryers; cycling and non-cycling. Cycling type refrigerant air dryers will cool a liquid mass, generally a glycol-water mixture, to a set-point and turn off. The liquid will go through an air-to-liquid heat exchanger to remove the heat from the compressed air. Referring to the cycling action, when the liquid mass goes above the set point, the refrigeration system will restart and cool the liquid mass again. The cycling refrigerant air dryers are more expensive, but they are more efficient.
Non-cycling refrigerant air dryers are more common. The refrigeration system continues to run through an air-to-air heat exchanger to cool the compressed air. It is similar to your AC system in your car. With this type of system, they are more susceptible to the environment, i.e., temperature, elevation, and humidity. So, adjustments are required for proper installation.
With both types of refrigerant dryers, the internal compressed air section is very similar. They will have a filter separator to remove the liquid that is created from the condensation from the cold temperatures. They also have an additional air-to-air heat exchanger. This will provide two important features for the refrigerated air dryers. As the cold air leaves the refrigerant section, it helps to cool the incoming compressed air. This will make the system more efficient. And as the hot incoming compressed air helps to warm the cold air leaving the dryer, it will stop the condensation of liquid water on the outside of the pipes. Like the dew forming on the grass during cool mornings, the same will occur with the compressed air piping system.
Moisture-laden compressed air can cause issues such as increased wear on the pneumatic tools, the formation of rust in piping and equipment, quality defects in painting processes, and frozen pipes in colder climates. Regardless of what products you’re using at the point-of-use, a compressed air dryer is undoubtedly a critical component of the compressed air system. Delivering clean, dry air to your EXAIR Products or other pneumatic devices will help to ensure a long life out of your equipment. If you wish to discuss more about your compressed air system or how EXAIR can provide a more efficient way to use that compressed air, an Application Engineer will be happy to assist you.
Wow, 2022 seems to have gone by very quickly! Perhaps it’s a signal I am getting old, perhaps it signals a busy life or maybe even a disruption in the space-time continuum…
In any case it has been another successful year at EXAIR, and we should acknowledge that we owe much of it to our customers, vendors and blog readers. Thank you for the support! Many wishes to all of you for joyful times during the holidays and a prosperous new year!
We will be closed over the Holidays on December 23,26, 30 and January 2, 2023.
We are looking forward to serving you and solving your process problems in 2023!
