Air & Water DO Mix – Why That’s A Problem for Compressed Air Systems

Wherever you go, humidity – and its effects – are an inescapable fact of life. Low humidity areas (I’m looking at you, American Southwest) make for a “dry heat” in the summer that many prefer to the wet & muggy conditions that areas with higher humidity (like much of the rest of the United States) encounter during the “dog days” of summer.

Regardless of human comfort level issues, all atmospheric air contains water vapor in some finite proportion…in fact, next to nitrogen and oxygen, it makes up a bigger percentage of our air’s makeup than the next eleven trace gases combined:

Reference: CRC Handbook of Chemistry and Physics, edited by David R. Lide, 1997.

And, because warmer air is capable of holding higher moisture concentrations (a 20°F rise in temperature doubles the potential for holding moisture), chances are good that it’ll become a bigger problem for your compressed air system in the summertime. So…how BAD of a problem is it? Let’s do some math. Consider a nice, typical summer day in the midwest, when it’s 80°F outside, with a relative humidity of 75% and we’ll use the data from the tables below to calculate how much water collects in the compressed air system:

Source: Compressed Air & Gas Institute Handbook, Chapter 3
Source: Compressed Air & Gas Institute Handbook, Chapter 3

Let’s assume:

  • An industrial air compressor is making compressed air at 100psig, and at a discharge temperature of 100°F.
  • The demand on the compressed air system (all the pneumatic loads it services) is 500 SCFM.

Table 3.3 tells us that, at 80°F and 75% RH, the air the compressor is pulling in has 0.1521 gallons per 1,000 cubic feet.

Table 3.4, tells us that, at 100°F and 100psig, the compressor is discharging air with a moisture content of 0.0478 gallons per 1,000 Standard Cubic Feet.

The difference in these two values is the amount of water that will condense in the receiver for every 1,000 SCF that passes through, or 0.1521-0.0478=0.1043 gallons. Since the demand (e.g., the air flow rate out of the receiver) is 500 SCFM, that’s:

500 SCFM X 60 min/hr X 8 hr/shift X 0.1043 gallons/1,000 SCF = 25 gallons of condensate

That’s 25 gallons that has to be drained from the receiver tank over the course of every eight hours, so a properly operating condensate drain is crucial. There are a few types to choose from, and the appropriate one is oftentimes included by the air compressor supplier.

So, you’ve got a condensate drain on your compressor’s receiver, and it’s working properly. Crisis averted, right? Well, not so fast…that 100°F compressed air is very likely going to cool down as it flows through the distribution header. Remember all that moisture that the hot air holds? Assuming the compressed air cools to 70°F in the header (a reasonable assumption in most industrial settings), a bunch of it is going to condense, and make its way to your air tools, cylinders, blow off devices, etc., which can cause a host of problems.

Reversible Drum Vacs have tight passages where contaminants (like pipe rust) can accumulate and hamper performance. Fortunately, they are designed to be easy to clean and returned to peak performance.

And…I trust you saw this coming…we’re going to calculate just how much condensation we have to worry about. Using table 3.4 again, we see that the header’s air (at 100psig & 70°F) can only hold 0.0182 gallons per 1,000 SCF. So, after cooling down from 100°F (where the air holds 0.0478 gallons per 1,000 SCF) to 70°F, that means 0.0296 gallons per 1,000 SCF will condense. So:

500 SCFM X 60 min/hr X 8 hr/shift X 0.0296 gal/1,000 SCF = 7.1 gallons of condensate

Qualified installers will have sloped the piping away from the compressor, with drip legs strategically placed at low points, so that condensate can drain, collect, and be disposed of…oftentimes via similar devices to the condensate drains you’ll find on the compressor’s main receiver. Good engineering practice, of course, dictates point-of-use filtration – EXAIR Automatic Drain Filter Separators, with 5-micron particulate elements, and centrifugal elements for moisture removal, are also essential to prevent water problems for your compressed air operated products.

Good engineering practice calls for point of use filtration and moisture removal, such as that provided by EXAIR Filter Separators.

EXAIR Corporation remains dedicated to helping you get the most out of your compressed air system. If you have questions, give me a call.

Russ Bowman, CCASS

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

EXAIR’s New Cabinet Cooler® System Calculator

For the longest time we have been using this form on EXAIR.com to get the information we needed to manually calculate the internal and external heat loads and ultimately make a recommendation on which Cabinet Cooler System would be best for that application! Typically it would take thirty minuets to an hour to get a email back from a application Engineer!

While the manual Cabinet Cooler Sizing Guide worked great (and we will still reply within 24 hours), we have been racking our heads over here to better that process and get you a solution faster than ever! Now you type in your information and you have a recommendation and a link to that product on the website where you can learn more or place an order! So you can go from form to order in less than 5 Minuets!!!! Check it Out HERE!!

By providing certain information like size of the enclosure, NEMA rating needed, and environmental conditions, this new calculator will sort through our large selection of ready-to-ship Cabinet Cooler® Systems and provide instant feedback on the best model number for any applicable electrical enclosure.  Taking the guess work out of the equation, EXAIR’s Calculator ensures the customer that they can be confident in selecting the correct product for their unique specifications. You can even Print the form for your records!

Cabinet Cooler Calculator

            EXAIR’s complete line of Cabinet Cooler systems include 120V AC, 240V AC and 24V DC thermostat voltage, continuous operation, type 316 stainless steel and high temperature models – all of which are selectable with the new calculator. Find this new tool on the website EXAIR.com, in the Knowledge Base Calculators, along with many other resources, such as the CAD Library and Application Database, which also help customers choose a perfect solution. Cabinet Cooler systems start at $534. https://www.exair.com/knowledgebase/calculator-library/cabinet-cooler-system-calculator.html

Jordan Shouse
Application Engineer

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

More And More Award Winning Products From EXAIR

As you might expect, a LOT of things have changed at EXAIR Corporation since 1983. Most of our current senior management had yet to graduate high school, and a fair number of current employees had yet to BE BORN. According to our computer system (another BIG change since 1983), our first ten customers were here in southwest Ohio (#11 was in Michigan), and now, we sell direct across the US & Canada, and our worldwide distributor network offers representation on six continents. One thing that hasn’t changed, though, is our founder’s vision of manufacturing quiet, safe, & efficient compressed air products for process improvement in just about any industry that uses compressed air. And THAT, dear reader, continues to gain high profile attention. The photo above shows the seven awards that our products have recently won, which were announced in 2021 or early 2022. Here’s a rundown:

Plant Engineering 2020 Product of the Year (Fluid Handling) GOLD AWARD:
1/2 NPT No Drip External Mix Air Atomizing Spray Nozzles

No Drip External Mix Atomizing Spray Nozzles

The 1/2 NPT models are the latest addition to our newest product line. The External Mix version offers the highest liquid flow rate, and largest pattern coverage. Among the applications where they’ve excelled so far are:

  • Snack food provider – applying flavoring to bulk snack materials.
  • Commercial bakery – spraying cooking oil onto pans used in a conveyor oven.
  • Sporting goods manufacturer – applying adhesive to the tops of skateboard decks to glue the grip tape on.

Plant Engineering 2020 Product of the Year (Material Handling Systems) GOLD AWARD:
2-1/2 NPT 303SS Threaded Line Vac

EXAIR's Threaded Line Vac Family
EXAIR Threaded Line Vac + Your Pipe + Compressed Air = Instant Conveyor System

For bulk material conveyance, it really doesn’t get any simpler than EXAIR Air Operated Conveyors. Stainless Steel models are especially popular when the environment – or the product – is corrosive, or hot…they’re good to 400F (204C), and can even be modified with High Temperature components for exposure up to 900F (482C). The Threaded versions have been successfully used to:

  • Recycle sprinkles applied to wafers into a return hopper in a candy production facility.
  • Replacing an auger conveyor to allow for homogenous mixing of grains & supplements in feed stock at an agricultural mill.
  • Providing a low cost solution to convey product into a hopper at a grain processing plant.

Plant Engineering 2020 Product of the Year (Maintenance Tools & Equipment) SILVER AWARD
Occupational Health & Safety 2021 New Product of the Year (Industrial Hygiene-Dust Control) WINNER
Occupational Health & Safety 2021 New Product of the Year (Health & Safety/Cleanup) PLATINUM

EasySwitch® Wet-Dry Vac

Like our Spray Nozzles product line, our Industrial Housekeeping Products line has also grown considerably over the years. The Deep Hole Vac-u-Gun and Heavy Duty HEPA Vac were real game changers when they came along, and the EasySwitch® Wet-Dry Vac Systems are likewise making an impact. Switching from wet to dry operation is, as advertised in the name itself, INCREDIBLY easy. Among our satisfied customers are:

Occupational Health & Safety 2021 New Product of the Year (Lab Safety) WINNER
Intellistat® Ion Air Gun™

The newest innovation in a long line of EXAIR static elimination solutions, the Model 8500 Intellistat® Ion Air Gun is made for laboratories, clean rooms, medical & electronic applications, and carries an ISO 14644-1 Class 5 rating for clean room use. Because of their rapid decay rates and lightweight construction, they’re used in a diverse range of applications and areas, including:

  • A supplier of fiberoptic parts uses an Intellistat® to remove dust and static charge from product prior to packaging.
  • A medical device manufacturer has one in a Class 7 clean room for silicone parts cleanliness.
  • A nutritional supplements maker uses their Intellistat® to remove static charge & powder residue from the tops of plastic bags before sealing them. The excess/residual powder causes them not to seal correctly.

Machine Design 2021 Big Idea! (Electrical Components) BRONZE AWARD
Gen4® Static Eliminator Power Supply

All EXAIR Gen4 Static Eliminators use one of two Power Supplies – your choice of the 2-port Model 7960, or the 4-port Model 7961.

EXAIR Static Eliminators produce ionized air via a Corona discharge, which requires high voltage, low current electricity. The Gen4® Static Eliminator Products feature armored & shielded cables with an internal ground, for safety and reliability. The ground path is completed through the cable and the Power Supply port, eliminating the need for an external ground connection. Faults in external ground connections result in the majority of the problems with those devices, so the internal ground is a “Big Idea!” indeed. The Gen4® Static Eliminator Power Supplies are switchable for 115VAC or 230VAC voltages, and are offered in 2, or 4 outlet designs, which can power any 2, or 4 EXAIR Static Eliminator Products. Like most EXAIR Intelligent Compressed Air Products, they’re used for a wide range of applications, in a wide range of industries:

If you’d like to find out more about these, or any of our other engineered compressed air products (we’re pretty proud of them all), give me a call. I can talk about them all day long…and sometimes I do!

Russ Bowman, CCASS

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

Vacuum Cups — Choosing the Right Size, Shape and Quantity

There is a lot to be said about EXAIR’s E-Vac systems. We have over 10 pages dedicated to this in our catalogue, and many blogs. Click here to see a great blog about selecting the correct E-Vac. Once you have selected the correct E-Vac Generator, we now need to set you up with the right accessories. The connectors and hoses are the easy part – this circles and squares. The magic comes when selecting the proper cup size, shape and quantity. Let’s start by looking at the 3 shapes available; Round, Oval and Bellow.

Round Cups are great for smooth, flat surfaces. They will grip and release quickly, and hold their shape well over extended use. These grip very well on vertical surfaces. For light lifting, use the non-cleated cups, and the cleated cups for heavy lifting. AS you see here we offer a small round and a large round cup.

Oval Cups have the largest surface and therefore provide the most vacuum. You will want to use these on the very heavy items. These are designed to handle flat rigid sheet materials like wood, glass, cardboard boxes and the bulkier items with a flat surface.

Bellow Cups are where we turn when your surface is uneven or textured. The “convolutions” or folds, provide a collapsible area that allows the cup to quickly compress when it reaches uneven surfaces. This cup will take longer to attach and to release due to the larger volume of the cup.

It’s important to note that all EXAIR vacuum cups are vinyl and are ideal for general purpose applications and will wear well. The Durometer rating is A50 and the Temp range is 32°F to 125°F.

From the information above, you should be narrowing down the shape of the cup you need based upon your product. But each of these shapes come in different sizes. Here is a table that shows you all the sizing options of each cup. You will want to keep in mind the size of your product, and the size of these cups. You will most likely need multiple cups to lift your item, so be thinking about how the actual size of the cups will fit evenly spaced on your product. The next step will get us home…

Our last step is to determine exactly how many cups we need to make this a viable and safe application. The first step is to calculate the amount of weight we need to lift. This is determined using a safety factor of 2 for cups positioned horizontally, and a factor of 4 for cups positioned vertically. So if you are moving a 10 lb box, and the cups are on top, you need to account for 20 lbs, and if the cups are on the sides, you need to account for 40lbs. Using the table below, you can see how many pounds that a single vacuum cup can hold, according to the “Hg applied. *** “Hg is based upon the E-Vac you chose earlier ***

As we put all this together it would look something like this. Using the example above, with a box size of 12″x12″x12″ weighing 10 lbs. We will be picking this up with the cups on top of the box, so our total safety weight is 20 pounds, You can see that there are many options that can get this job done. You can use 1,2,3, or even 4 vacuum cups. 1, 2, or 3 E-Vac’s. The key here is to think about safety first, and then consider what issues may arise if something goes wrong. In this scenario, I would consider what is in the box. But if it falls, will it break? If it breaks how much will that cost you?. Also, what happens to production if something tweaks the cups and boxes start piling up. If the penalties are low, I would use 1 cup like a large round (900756) and 1 E-Vac that pulls 10 Hg”. This gives me 34.8 pounds of lift. More than enough. If the box falls and will cost a lot of money, break, slow the process, the 1 cup option is still ok, but I would make this 3 small round cups (900755) and 1 E-Vac that will pull 10 Hg”. This gives me 12.1 pounds of lift on each cup, so if one doesn’t seat correctly, the other 2 (or even one) will still protect me. There are multiple other options as well.

At EXAIR, we have a lot of experience walking through these scenarios and helping make recommendations. Please feel free to call and ask for any of the application engineers for questions or assistance.

Application Engineer

Brian Wages

EXAIR Corporation
Visit us on the Web
Follow me on Twitter