Six Steps to Compressed Air Optimization: Step 3 – Use Efficient and Quiet Engineered Products

Compressed air is expensive, and you should treat it that way.  Frequent readers of the EXAIR Blog are familiar with our Six Steps to Compressed Air Optimization, and you may have seen these recent installments on Steps 1 and 2:

Six Steps to Optimization: Step 1 – Measure the Air Consumption

Six Steps to Compressed Air Optimization: Step 2 – Find and Fix Leaks

Now, there isn’t a strict order in which you MUST perform these steps, and they’re not all applicable in every air system (looking at you, Step 5: Use Intermediate Storage,) but these are likely the steps that a certified auditor will take, and the order in which they’ll take them.  If you’re looking for immediate, quantifiable results, though, Step 3 is a great place to start.  Consider:

  • A 1/4″ copper tube blow off can consume as much as 33 SCFM when supplied with compressed air at 80psig.  It’ll give you a good, strong blow off, for sure.  You can crimp the end and get that down to, say, 20 SCFM or so.  Or, you can install a Model 1100 Super Air Nozzle with a compression fitting, and drop that to just 14 SCFM.
    • If you’re tracking your compressed air usage, you’ll see that replacing just one of them saves you 45,600 Standard Cubic Feet worth of compressed in one 5 day (8 hour a day) work week.  That’s $11.40 in air generation cost savings, for a $42 (2020 List Price) investment.
    • If you spend time in the space where it’s installed, you’ll notice a dramatic improvement in the noise situation.  That sound level from the copper tube is likely over 100 dBA; the Super Air Nozzle’s is only 74 dBA.
This user was only a handful of compression fittings & nozzles away from over $800 in annual compressed air savings.
  • Drilled pipes are another common method to create a blow off.  They’re easy & cheap, but loud & expensive to operate.
    • A pipe drilled with 1/8″ holes and supplied @80psig will consume 13 SCFM per hole, and the holes are typically drilled on 1/2″ centers.
    • An EXAIR Super Air Knife consumes only 2.9 SCFM per inch of length, and because it’s an engineered product, it’s a LOT quieter as well.  Drilled pipes are, essentially, open ended blow offs just like the copper tube mentioned above.  When you let compressed air out of a hole like that, all the potential energy of the pressure is converted to force…and noise.
    • Drilled pipes are among the worst offenders; almost always well in excess of 100 dBA.  Super Air Knives generate a sound level of only 69 dBA with 80psig compressed air supply.  They are, in fact, the quietest compressed air blowing product on the market today.
This Model 110048 48″ Aluminum Super Air Knife replaced a drilled pipe for over $5,000 annual compressed air savings.

These aren’t just theoretical “for instances” either – the data, and the photos above, come from actual Case Studies we’ve performed with real live users of our products.  You can find them here, and here (registration required.)

These are two examples of EXAIR product users who only used Step 3 of our Six Steps, although BOTH of them were already practicing Step 4 (Turn off the compressed air when it isn’t in use)…they had their blow offs supplied through solenoid valves that were wired into the respective machine controls, and the Air Knife user HAD to do Step 6 (Control the air pressure at the point of use) to keep their product from being blown clear off the conveyor..

But we’ll be happy to help you with optimizing your compressed air system using any or all of the Six Steps. Give me a call.

Russ Bowman
Application Engineer
EXAIR Corporation
Visit us on the Web
Follow me on Twitter
Like us on Facebook

How to Pick the Right Atomizing Spray Nozzle

Atomizing spray nozzles atomize fluids with compressed air to create a fine spray in a variety of patterns for a variety of uses. They are commonly used to mark products, paint or coat, cool, reduce dust, lubricate and clean parts.

With the numerous types of Atomizing Nozzles, it can be challenging to sift through all the information. But with a few basic questions you can narrow down the right nozzle type for you and your application:

142 distinct models. 8 different patterns. Liquid flow rates from 0.1 to 303 gallons per hour. If you’ve got a spraying application, EXAIR has an Atomizing Nozzle for you!

Are you using a pressurized liquid feed? In some cases, a pressurized liquid source is not available for the nozzle, so you would have to rely on a gravity or siphon fed nozzle. While you lose the complexity of having a liquid pump pressurizing your liquid, you do have a few draw backs. Your siphon height is typically with in 36” so your liquid source has to be fairly close to your nozzle. Siphon fed nozzles are hard to turn off and on, they are best used for applications where you are continuously spraying a low viscosity liquid with a low gph.  

Internal Mix Atomizing Spray Nozzles

What is the viscosity of the fluid? Another deciding factor is the viscosity of the liquid you are spraying. Different nozzles are designed for different viscosity. For example, two of the main nozzle types are internal mix nozzles and external mix nozzles. They function just like they sound, internal mix nozzles mix the compressed air and liquid source inside the nozzle. And because of this they typically can not spray liquids over 300 cP. And because external mix nozzles mix the liquid and air outside the nozzle, they can handle liquids well above 300 cP.

What is the liquid flow rate in gallons per hour(gph)? Another factor in choosing the right nozzle is if your application has a set gph you are looking to achieve. Some nozzles are designed to flow more liquid then others. For example, the external mix nozzles inherently flow more liquid then the internal mix. As there is less restriction on the liquid flow. If you are looking for even higher gph you can source a liquid only atomizing nozzle, its going to give you a large bump in gph. But your droplet size will suffer with the liquid only nozzles.

Full Cone Liquid Only Atomizing Spray Nozzle

What droplet size are you looking for? Fine droplet sizes are one of the primary reasons atomizing nozzles are used. Benefits of small droplet sizes include even coating and liquid conservation. Internal mix nozzles will do the best at providing the smallest droplet size possible. While external mix and liquid only will give you larger droplet sizes but they will give you a larger gph some applications need.  

Should I use a No-Drip option?  The No-Drip option positively shuts off liquid flow when the    compressed air supply is shut off.  One benefit of this is appreciated in coating applications, where an errant droplet of liquid would mar an otherwise smooth, even coating.  Operationally, though, it also means you can precisely turn the liquid flow on & off, in short, quick bursts, up to 180 times a second.

No Drip External Mix

If you are in the need for a Liquid Nozzle to assist in your facility, please reach out! We have a team of application engineers waiting from 8AM – 5PM EST to help you size and fit a product to your specific application! 

Jordan Shouse
Application Engineer

Send me an email
Find us on the Web 
Like us on Facebook
Twitter: @EXAIR_JS

O-Rings, Seals, Gaskets, Maintenace, Filtration – They All Matter

I’ve mentioned it before and I’ll say it again. You can’t teach experience. This was told to me by a mentor at a previous job and of course, younger me thought, “Yeah, yeah I know all I need to know.”  Well, younger me was an idiot and learned many things through experience. Sometimes I am still a slow learner and eventually, I remember those experiences and make decisions based on them. So what does this have to do with o-rings, seals, and gaskets?

I’m in the midst of a light construction project in my house and have reached a stage where some tools that I do not have would come in handy and make the job faster. Younger me would have justified purchasing a new one, experienced me understands a budget and reached out to my network of friends and a good friend said they had the tool I needed. This was a compressed air powered framing nail gun. Straight through nailing, no-problem, toe-nailing, no-problem, this thing won’t break a sweat and your arms will be stronger by the time you are done using it while your thumbs are screaming thank you for not smashing me a hundred times.

The Framing Nail Gun in question

This loan did come with two conditions, one was, he didn’t have any nails to give with it. This was not a problem as I wouldn’t expect a friend to give me free fasteners with a tool loan. The second is the one that concerned me, he said, it does leak a little air but it should still shoot just fine. After working in the compressed air industry for over a decade I have experienced this many times. At that point I knew if you could hear it, chances were it was a bad leak. Upon further inspection, there was a cylinder gasket and rubber spring that were in pieces.

Old Spring Bumper and Main Cylinder Gasket

Gasket pieces and dirty air can result in catastrophic failures.

Nothing that a trip to a local business couldn’t take care of.  A few new parts and discussion with their knowledgeable staff and I had the information needed to rebuild this nail gun to functioning status.

New vs. Old

Oddly enough, my experience and expertise with how the EXAIR products like the No-Drip Air Atomizing Liquid Spray Nozzles operate and how to rebuild them, provided a good foundation about how this tool worked. This repair ended up being very similar to the rebuild on a No-Drip Spray Nozzle.

This story is two-fold, filtration could have prevented a lot of the damage to this gun. This gun uses a good amount of air volume at an expedient pace so keeping it clean and clear of debris helps extend the lifetime of internal parts.  See my video on what happens without filtration below.

The second part is that maintaining and understanding processes to clean/rebuild are crucial to sustainable function of a machine. The cleaning process for this gun was fairly straightforward and using the correct lubricant for reassembly was another critical role. This culminated in a framing nail gun that can now be used to further my project and will more than likely live another decade before needing a rebuild again. That is if filtration and proper lubrication are followed.

Had I not obtained experiences throughout my career that helped me to understand how this tool functioned, the worth of a reliable network of vendors, and the necessity to complete tasks that take me out of my comfort zone I wouldn’t be in the place I am today. Because I have the experience and the network to ask for help it enables me to keep machines running that could have cost valuable production hours had this been a production environment.

EXAIR stocks rebuild kits, gaskets, shims, and parts for all of our product lines which may require a repair. For products which need to be cleaned in order to return back to new performance, we have the instructions or can do it for you here. From time to time they may need a repair or refurb in order to keep functioning at peak performance. If you want to build your trusted network or learn more about how to rebuild or clean EXAIR products, contact us.

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF

Issues and Problems with Pressure Drop

 

Super Air Knife Install Sheet

Pressure drop comes in different forms, and it causes inefficiencies within your pneumatic system.  EXAIR writes statements in the installation manuals to help find the correct pipe sizes to supply the different products.  (Reference Super Air Knife Installation Manual above).   But there are other areas that can affect the performance.  These can be fittings, tubing, valves, and accessories.  In this blog, I will cover some pitfalls that can minimize the potential of your EXAIR products.

Pressure drop by definition is a difference or loss in pressure.  A properly sized Filter Separator will typically have a pressure drop of 5 PSID (0.3 bar) at the rated conditions.  So, if you start with 100 PSIG (6.9 bar), the air pressure after the filter separator will be 95 PSIG (6.6 bar).  But what happens when a filter separator is undersized or too small?  The pressure drop will be much higher.  So, if the pressure drop is 30 PSID (2 bar), then the downstream air pressure will only be 70 PSIG (4.8 bar).  At that pressure, you may not be able to get the performance that is required to do the job.

The first thing in determining these potential issues is what I like to call forensics.  If you can install a pressure gage at the inlet of any EXAIR product, then you can deduce if a potential problem is within your setup.   For example, if the Pressure Regulator is at 100 PSIG (6.9 bar), and the pressure gauge at the inlet is reading only 60 PSIG (4.1 bar), then there is a pressure drop of 40 PSID (2.8 bar) between these two points.  You can look in this area for the problem or problems.  If the gauge on the Pressure Regulator goes down as well when you are operating, then the problem area is upstream of the Pressure Regulator.  This can be from the pipe size or the air compressor.

The most common issues are fittings and tubing.  With fittings, small openings may not allow enough air to pass through.  Above is a photo of some typical fittings.  You notice that the right side of the chart has large enough openings to decrease pressure drop.  In some instances, quick connect fittings are commonly used to easily connect or disconnect pneumatic devices; but if you use too small or too many of these fittings, they can cause a large pressure drop.

The other problem is with the inner diameter of tubing, hoses, or pipes that are not properly sized.  Russ Bowman, a colleague, created a video showing the issues with improperly sized plumbing.  It is a very interesting video that shows the effect on a Super Air Knife.

If you want to get the most from your EXAIR products, you will need to reduce the amount of pressure drop in your system.  Pressure drop is wasted energy and can affect your pneumatic system.  You can follow my recommendations above.  Or if you would like to discuss your setup with an Application Engineer, we will be happy to assist.

John Ball
Application Engineer

Email: johnball@exair.com
Twitter: @EXAIR_jb