EXAIR Super Air Knives: Controlling the Force

EXAIR has been manufacturing Intelligent Compressed Air® products since 1983.  In the beginning, the Standard Air Knives and Full Flow Air Knives were very effective at that time.  But as leaders in this market, EXAIR did not want to stop there.  We were able to engineer a more efficient and more powerful air knife, the Super Air Knife.

Super Air Knife has 40:1 Amplification Ratio

Bernoulli’s principle explains how a high velocity fluid can generate a low pressure.  The EXAIR Super Air Knife creates a high velocity air stream to produce a low pressure to entrain ambient air.   What does this mean for you?  It will save you much money by using less compressed air.  The mass of the ambient air is added into the air stream to give a strong blowing force.  The Super Air Knife has an amplification ratio of 40:1. For every 1 part of compressed air, 40 parts of ambient air is drawn into the blowing air stream.  Ambient air is free, and compressed air is expensive.  EXAIR was able to engineer a design to use the Bernoulli’s principle to make one of the most efficient air knives in the market place.    In this blog, I will discuss how you can change the air usage and force of the EXAIR Super Air Knives.

We manufacture and stock the widest range in lengths and materials.  To start, EXAIR has Super Air Knives ranging from 3” to 108” (76mm to 2,743mm) in three different materials; aluminum, 303 stainless steel, and 316/316L stainless steel.  There is no-one else in this industry that can manufacture to those lengths.  EXAIR also offers Super Air Knives in PVDF material with Hastelloy hardware for chemical resistant applications from 3” to 54” (76mm to 1,372mm).  Depending on the application requirement, temperature, chemical resistance, and OSHA and FDA regulations, we probably will have one on the shelf for you.  If EXAIR does not have it, we can make special air knives in different lengths and materials to best fit your application.

Pressure Regulators

To adjust the force and air usage a Pressure Regulator is a very helpful tool. The regulator would be considered a fine adjustment for the Super Air Knife.  With the laminar flow, the force is very consistent across the entire length; so, you can “dial” in the exact force.  EXAIR always recommends to use the least amount of pressure to “do the job” because this will save you even more money.  For the coarse adjustment, EXAIR Super Air Knives have replaceable shims.  So, you can increase or decrease the gap to get a variety of force ratings.  The Aluminum version uses colored plastic shims for visual verification.  They come stock with a 0.002” (0.05mm) red shim installed.  We have other thicknesses in our Shim Sets which includes a 0.001” (0.03mm), 0.003” (0.08mm), and a 0.004” (0.10mm) colored as amber, green, and tan respectively.

The Stainless Steel Super Air Knives come with a stainless steel shim for higher temperatures and chemical resistance.  Stock units have the 0.002” (0.05mm) thickness as well.  The Shim Sets come with three additional 0.002” (0.05mm) shims to stack.  EXAIR does have the ability to manufacture other thicknesses in stainless steel.  Similarly, the PVDF Super Air Knives use a PTFE shim for maximum chemical resistance.  It is also 0.002” (0.05mm) thick, and there are three more shims in the Shim Set.

This unique feature of using shims allows for the most flexibility in creating forces for different applications ranging from a blast to remove rocks from a conveyor to a breeze for light duty work.

We can include the pressure regulator, filter, and Shim Sets in our standard kits.  It will make our Super Air Knives a more complete system that is properly sized.  With the today’s cost in making compressed air, it is important to do it as efficiently as possible.  And with the Pressure Regulator and Shim Sets available, you can control the blowing force and air usage.  From now until December 31st, EXAIR is having a promotion.  You will receive a model 1210 Safety Air Gun for free, a $91.00 value, with qualified purchases.  (Check it out HERE).  If you have any questions about the Super Air Knife or if you would like to discuss an application, you can contact an Application Engineer at EXAIR.   We will be glad to help you.

John Ball
Application Engineer

Email: johnball@exair.com
Twitter: @EXAIR_jb

Compressed Air: Only as Intelligent as Your Accessories

How often have you seen a compressed air system functioning at 100% efficiency? Do you have the right accessories to provide a source of clean air at the proper pressure? Even with the right accessories, have they been maintained in good working order? Chances are that some of your components are in fact in need of attention such as a clogged filter, improper regulator or maybe undersized hoses. Your air compressor is only as intelligent as the weakest component in your system.

This is why you need to make sure all of your EXAIR accessories are properly fitted and located in the most efficient locations. Your compressor is capable of producing compressed air but your accessories will allow it to function the way it is meant to function. Using accessories and using them in the right manner is the intelligent choice, it will minimize your maintenance while increasing your energy efficiency for the life of your compressor. Let’s review a few of the most important compressed air accessories you should consider.

Filter Separators: Filters remove and separate water, dirt and scale from your compressed air system to keep your air clean and output pure. Clean air keeps your air products and machines more efficient and reduce the frequency of maintenance. Filter Separators will accumulate particulate matter naturally so they will need cleaned and/or replaced filter elements regularly depending on your operating environment. EXAIR provides Filter Separators and recommend they be installed prior to an Oil Removal Filter, pressure regulator or valve.

Filter Separators

Oil Removal Filters: Many air compressors use oil to lubricate therefore the risk of oil in your air lines is imminent. Although oil may not affect the compressed air system itself it can become a problem with products which do not require oil and have small air gaps. It can also be problematic if oil is blowing on to packaging or the final product. Keep this in mind and remember that oil should be removed from compressed air lines in certain instances. EXAIR’s oil removal filters will remove oil and solid particulate found in many compressed air systems.

Pressure Regulators: Regulators adjust the air pressure being supplied by your air compressor to the level that you require at the point of use. For instance your compressor generates 150 PSI but your compressed air product only requires 80 PSIG, the regulator can adjust the pressure to the desired setting and also relieve undue pressure on fittings, hoses and tools. Reducing pressure at the end-use product will also reduce the air consumption. Almost every compressed air application will use tools with varying pressure ratings making EXAIR Pressure Regulators a must-have accessory.

Hoses & Fittings: Hoses and fittings wear with time. Common issues are kinking, bending, leaks and contaminants, they should be checked often and replaced when required. Another common problem with hoses is that they are either too long and not as efficient or too short which can cause your employees reduced productivity. EXAIR offers STAY SET Hoses, Conveying Hose, Coiled Hoses and Compressed Air Hoses of different sizes and lengths. Our selection of compressed air fittings insures you can get all you need from one location.

Receiver Tanks: The use of receiver tanks can improve your overall system efficiency. Storage receivers can be placed near equipment that consume short duration of high flows of compressed air that might cause localized low pressure. EXAIR’s 60 Gallon Receiver Tank placed near the point of use can smooth out the high flows so as not to cause the start of an extra air compressor or cause localized low pressure.

If you would like more information regarding how proper use of EXAIR’s accessories can make your compressed air consumption more intelligent please contact me or any of our qualified Applications Engineers to discuss your applications.

Eric Kuhnash
Application Engineer
E-mail: EricKuhnash@exair.com
Twitter: Twitter: @EXAIR_EK

 

Piping and Instrumentation diagrams (P&ID)

When it comes to drawings and diagrams to map out a process system, the piping and instrumentation diagrams (P&ID) are a great way to situate and find components.  They use different symbols to represent the type of products, the layout in the system, installation, and process flow.  These standard symbols are created by ANSI or ISO.  They are used in electrical, hydraulic, and pneumatic processes.  Since EXAIR has been manufacturing Intelligent Compressed Air Products since 1983, I will cover some pneumatic symbols and the process flow in this blog.

A colleague, Russ Bowman, wrote an article about “Knowing Your Symbols Is Key To Understanding Your Drawings”.  As a reference, air compressors are the start of your pneumatic system, and there are different types as represented by the symbols below.

The one on the left can be used for any air compressor. The others denote specific types of air compressor (from left:) Centrifugal, Diaphragm, Piston, Rotary, and Screw.

Air compressors are considered the fourth utility in industries because they use so much electricity; and they are inefficient.  So, you need to use the compressed air as efficiently as possible.  As a typical pneumatic system, the air compressors, receiver tanks and compressed air dryers would be on the supply side.  The distribution system, or piping, connects the supply side to the demand side.  This symbol is represented by a simple line.  The demand side will have many different types of pneumatic devices.  Since there are so many, ANSI or ISO has created some common types of equipment.  But if there isn’t a symbol created to represent that part, the idea is to draw a basic shape and mark it.

From top left, and then down: Automatic Drain Filter Separator, Pressure Regulator, and Super Air Knife

As an example, if I were to do a P&ID diagram of the EXAIR Super Air Knife Kit; it would look like the above diagram.  The kit will include the Super Air Knife with an Automatic Drain Filter Separator and a Pressure Regulator.  The Filter Separator is a diamond shape and since it has an Automatic Drain, a triangle is placed at the bottom.  Filter Separators are used to clean the compressed air and keep the Super Air Knife clean.  The Automatic Drain will discard water and oil from the filter bowl when it accumulates over a float.  The next item is the pressure regulator which is represented by a rectangle with an adjustment knob to “dial in” the desired blowing force.  And at the end, we drew a rectangle, which does represent a Super Air Knife, as marked.

Using the P&ID diagram for the process flow is also important.  You noticed that the Filter Separator will come before the Pressure Regulator.  This is significant when installing this system.  Remember the statement above about “using your compressed air as efficiently as possible”?  Inefficiencies come from two basic areas; pressure drop and overusing your compressed air.  Pressure drop is based on velocity.  The lower the velocity, the lower the pressure drop.  If the Filter Separator is placed after the Pressure Regulator, the lower pressure will increase the velocity.  Since air expands at lower pressure, the volume of air will increase.  And since the area of the compressed air pipe is the same, the velocity will have to increase.   For the second part with overusing compressed air, the Pressure Regulator will help.  You want to use the lowest amount of air pressure as possible for the Super Air Knife to “do the job”.  The lower air pressure will use less compressed air in your operation.

EXAIR products are engineered to be safe, efficient, and effective in your compressed air system.  If you need help to place them in your P&ID diagrams, an Application Engineer can help you.  It is important to have the pneumatic devices in the proper place, and if you want to efficiently use your compressed air, you can use EXAIR products for your blow-off devices.

John Ball
Application Engineer

Email: johnball@exair.com
Twitter: @EXAIR_jb

Undersized Regulators Create Performance Problems with Compressed Air

“I have a Cabinet Cooler installed on my panel but it isn’t getting the temperature down cold enough. Can you quote me for a duplicate system to install on this panel?” This was a recent inquiry from a customer regarding an electrical enclosure that they had installed in their plant. The Cabinet Cooler was producing cold air, but not enough to keep the cabinet at their desired temperature. It would seem logical that they need additional capacity, right? While that could be the case, in this instance it most definitely was not.

When we get questions like this, we first want to take a closer look at the current installation. The cooling capacity for each system is published in our catalog. BUT, in order to rate a cooling capacity for any type of cooling system, some assumptions must be made. All Cabinet Coolers are specified with 70°F compressed air fed to the Cabinet Cooler at a pressure of 100 PSIG. In addition, each cooler has a specified volume of air that it must utilize in order to produce that rated cooling capacity. If any one of those parameters change, so does the overall cooling power.

In this particular case, the customer had installed a non-EXAIR pressure regulator just upstream of the cooler. Upon looking at the specifications for this regulator, it was found that the overall volume of air it can deliver was just 10% of the overall volume needed to produce the rated 1700 Btu/hr. They didn’t need another Cabinet Cooler System, they just needed to remove that restriction! Upon learning that it needed 100 PSIG, they removed the regulator and supplied full line pressure. No more heat alarms for that shift!

CC undersized valve

Rather than purchasing and installing an unnecessary system, they were able to get back up and running just by removing the problem upstream. At EXAIR, we want to make sure that you’re getting the most out of our products. Just because you call and inquire about a new purchase doesn’t necessarily mean that you need it. We’re here to help you determine if something is afoul with the current setup and make sure you have all of the knowledge necessary to rectify it.

We’re right in the middle of summer, and boy is it hot out there. If you have panels that are overheating and creating problems for you in your processes, give us a call. With Cabinet Cooler Systems ready to ship same day from stock (with properly sized regulators) you can have it fixed by tomorrow.

Tyler Daniel
Application Engineer
E-mail: TylerDaniel@EXAIR.com
Twitter: @EXAIR_TD