Tag: Super Air Nozzles

Standard Temperature and Pressure: What is STP?

Published on by John BallLeave a comment

When it comes to volumetric flow rates, you probably noticed the prefix of an “S” for SCFM and SLPM, or an “N” for NM3/hr.  The “S” prefix is for Standard conditions, and the “N” prefix is for Normal conditions.  For practical reasons, they are the same thing.  What does this mean? 

Let’s look at the Ideal Gas Law in Equation 1:

Equation 1:

PV = nRT 

P – Pressure

V – Volume

n – No. of moles

R – Ideal Gas constant

T – temperature

Since air is compressible, it will react in different ways.  If we keep the volume the same and lower the temperature, the gas pressure will go down.  If we keep the temperature the same and decrease the volume, the gas pressure will go up.  If we go to a higher elevation, the number of moles is reduced, which will lower the gas pressure.  With the different degrees of changes, it is difficult to compare.  So, organizations decided to place a standard on these conditions to help compare results.  The definition is referred to as STP, or Standard Temperature and Pressure. 

In most cases, the Standard Temperature and Pressure is set at 20oC and 1 atm (1.013 bar).  If we transition all pneumatic units to this condition, we can then compare the results for each product.  We can determine which units actually use less compressed air or have higher forces.  Or if we decide to use a different STP, we can do that as well as long as we use the same temperature and pressure. 

I like to think of it like an air-filled balloon floating on top of the water.  This would be the “Standard” or “Normal” condition.  As you take the balloon into deeper water, more pressure is applied to the balloon, and the volume will decrease.  This is because air is compressible.  The balloon still has the same amount of air by weight (as the volume decreases, the density increases).  If you return to the surface, the balloon will expand back to the original size.  When doing comparisons, we need to be in the same condition, or for the balloon example, it will look like the balloon will need less air at lower depths than at the surface.   

The reason for this explanation is that some competitors like to use lower pressures to rate their products.  As an example, Competitor A rates their nozzles at 5 bar (72.5 psig).  EXAIR uses 5.5 bar (80 psig) for most of our products.  By comparison, we cannot say if one unit uses more or less compressed air unless we set them at the same conditions.  The best place to compare is at a Standard Temperature and Pressure, or STP.   I go into more detail in my blog about air flows with “CFM, ICFM, ACFM, SCFM: Volumetric Flow Rates Explained”.  EXAIR offers Super Air Knives, Super Air Nozzles, and Super Air Amplifiers to efficiently blow compressed air.  So, when a company states a compressed air flow, verify the pressure and temperature at which they recorded that information.  It will help you to be more in tune with what you are getting (allow for an apples to apples comparison). If you need any help in doing comparisons, an Application Engineer at EXAIR will be happy to assist you. 

John Ball
Application Engineer

Email: johnball@exair.com
Twitter: @EXAIR_jb

Photo:  balloon helium air flying bright by stux.  Pixabay license

Plumb it Right for Full Performance!

Published on by Jordan T ShouseLeave a comment

Many times when we provide the air consumption of an EXAIR product, we get a response like…. “I’ve got plenty of pressure, we run at around 100 PSIG”. While having the correct pressure available is important, it doesn’t make up for the volume requirement or SCFM (Standard Cubic Feet per Minute) needed to maintain that pressure. We commonly reference trying to supply water to a fire hose with a garden hose, it is the same principle, in regards to compressed air.

When looking to maintain an efficient compressed air system, it’s important that you use properly sized supply lines and fittings to  support the air demand (SCFM) of the point-of-use device. The smaller the ID and the longer the length of air supply line, it becomes more difficult for the air to travel through the system. Undersized supply lines or piping can sometimes be the biggest culprit in a compressed air system as they can lead to severe pressure drops or the loss of pressure from the compressor to the end use product.

Take for example our 18″ Super Air Knife. An 18″ Super Air Knife will consume 52.2 SCFM at 80 PSIG. We recommend using 1/2″ Schedule 40 pipe up to 10′ or 3/4″ pipe up to 50′. The reason you need to increase the pipe size after 10′ of run is that 1/2″ pipe can flow close to 100 SCFM up to 10′ but for a 50′ length it can only flow 42 SCFM. On the other hand, 3/4″ pipe is able to flow 100 SCFM up to 50′ so this will allow you to carry the volume needed to the inlet of the knife, without losing pressure through the line.

Pipe size chart for the Super Air Knife

Another problem area is using restrictive fittings, like quick disconnects. While this may be useful with common everyday pneumatic tools, like an impact wrench or nail gun, they can severely limit the volumetric flow to a device requiring more air , like a longer length air knife.

1/4″ Quick Connect

For example, looking at the above 1/4″ quick disconnect, the ID of the fitting is much smaller than the NPT connection size. In this case, it is measuring close to .192″. If you were using a device like our Super Air Knife that features 1/4″ FNPT inlets, even though you are providing the correct thread size, the small inside diameter of the quick disconnect causes too much of a restriction for the volume (SCFM) required to properly support the knife, resulting in a pressure drop through the line, reducing the overall performance.

If you have any questions about compressed air applications or supply lines, please contact one of our application engineers for assistance.

Jordan Shouse
Application Engineer

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Blow Off Systems for the “W”

Published on by bdwagesLeave a comment
Image by Peggy und Marco Lachmann-Anke from Pixabay

Many times we have tendencies to overcomplicate things. I remember a time when I was visiting my sister in Phoenix, and she was making a fancy 3D Scooby-Doo cake for my nephew’s 4th or 5th, and she needed the brown icing. Now when decorating these cakes, the common practice is to make white icing and use food coloring to make all of the other colors you need. She left that morning around 10:00 to look for brown food coloring. Around noon she called to tell us that she could not find brown food coloring at any store on this side of town, and was driving to the far side of the city to look at those stores. I asked her why she couldn’t just use chocolate icing, and she was having no part of it. She was so laser focused on her solution that she couldn’t hear that that chocolate icing is also brown… Fast forward to 6:30 PM, and she comes walking through the door frustrated and exhausted from her day of going store to store all over the large city looking for the elusive brown food coloring. As you can probably guess, she had chocolate icing with her because it finally hit her that the chocolate icing is brown… . The cake turned out amazing, and the lesson was learned.

So, why this story? I feel that in life and in business we sometimes leave our blinders on and become laser focused on one certain way of doing something. We know that the way we se it will work, and think that we know best, and we are going to make it happen exactly how it is playing out in our head. No other way seems possible, and when someone offers up a simpler solution, our immediate thought is “it can’t be that simple”, or “if it’s that simple of a solution, there is no way it could work”. Have you ever said these things? As an application engineer, I take a lot of calls from people that are much smarter than me with grandiose plans. Many times the problem they need to solve, is much simpler than the solution they have in mind. I’ve seen elaborate plans, that probably took hours if not days to develop, come down to simply needing a simple out of the box Blow-Off System.

At EXAIR, we specialize in intelligent compressed air products with a primary focus on blow off, drying, and cooling. When it comes to these things, our product lines (pointedly for this blog, our Air Nozzles and Jets) are head and shoulders above our competition. The vast majority (with the exceptions of the High power or high force nozzles – for obvious reasons) all meet both OSHA standards concerning noise and dead end pressure. Here is a list of all of our Super Air Nozzles showing the SCFM, Force and Decibels:

Our Blow Off Systems (some sample pics below) are a fantastic and smart solution for so many applications. It really doesn’t get much easier than this, a Magnetic base, a Stay-Set Hose, and a Super Air Nozzle, all in one. I feel that these are heavily under utilized. Simply connect your air hose, bend the Stay-Set Hose to the direction of spray that you need, and boom, Bob’s your uncle…

Mag Bases come with one or two outlets. Stay Set Hoses come in lengths from 6″ to 36″.

Sometimes things can be as simple as using chocolate icing for brown icing, or using an EXAIR Blow-Off System in your application. Of course if you need more than that, we will help you find the right solution for you. Call today to speak with an experienced application engineer that is eager to help.

Thank you for stopping by,

Brian Wages

Application Engineer

EXAIR Corporation
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Building Flexibility with Stay Set Hoses and Magnet Bases

Published on by EricKuhnash@EXAIR.comLeave a comment

You can build in flexibility when purchasing Super Air Nozzles, Air Knives, Safety Air Guns and other products from EXAIR. Consider adding our Stay Set Hoses and Magnet Bases to create flexibility and ease of set-up to your process. These accessories will improve your project and reduce your set-up time.

EXAIR has a variety of lengths in our Stay Set Hoses ranging from 6″ up to 36″ in 1/4 MNPT x 1/8 FNPT or 1/4 MNPT x 1/4 MNPT fittings. The Stay Set hoses are used mainly where frequent repositioning is required. You can bend and the hose to your desired position and since the hose has “memory” it will not creep or bend. It will keep this position until physically moved to the next position. These hoses can withstand temperatures up to 158 F (70C).

EXAIR Magnet Bases can be used when frequent movement of air product is required. These powerful magnets permit horizontal or vertical mounting. A valve is used to vary force and flow. The choice of single outlet, dual outlet and Swivel are available.

The combination of our Stay Set Hoses and Magnet Bases will accommodate Air Nozzles and Jets along with our smaller Air Knives, Air Wipes, Super Air Amplifiers and can also be assembled to our Safety Air Guns. There are many uses for our Stay Set Hoses and Magnet bases. While purchasing our Intelligent Compressed Air products consider all of our accessories to help your projects. If you have an application and have questions please contact EXAIR and one of our Application Engineers to answer your questions.

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