Vacuum Generator System Selection – EXAIR E-Vacs

E-Vac Vacuum Generators are a highly efficient, versatile compressed air vacuum pump. Their versatility allows them to be adapted to many applications such as pick and place, clamping or vacuum forming. They’ve also been used in more unique applications like wood veneer pressing and basketball deflation.

EXAIR manufactures (3) types of E-Vacs – Low vacuum generators for porous materials, like cardboard, generating up to 21″ Hg with vacuum flows as high as 18.5 SCFM. Our high vacuum generators, designed for use with non-porous materials like glass or steel sheets, produce vacuum levels up to 27″ Hg and up to 15.8 SCFM of vacuum flow. The adjustable generators provide flexible vacuum performance, up to 25″ Hg and 81 SCFM,  which can be easily adapted to meet the application.

EXAIR E-Vacs provide instantaneous vacuum response, and are engineered for high efficiency to minimize air consumption.

 

When making a selection, there are a few key areas you want to consider:

Is the material porous or non-porous?

  • This will allow you to select the proper type of vacuum generator to fit the application and the type of vacuum cup best suited for the process.

 

What is the weight of the part and how will it be lifted?

  • If the part is being lifted where the vacuum cups will be positioned horizontally, like on top of a sheet of glass, you want to use a safety factor of 2 times the actual weight of the part. In processes requiring the cups be positioned vertically on the part, such as picking up a sheet of plywood and hanging it on an overhead conveyor, a safety factor of 4 would be used.

 

How many Vacuum Cups do I need?

  • Consider the quantity and placement to evenly distribute the weight for safely moving the material.
  • Depending on the maximum vacuum the generator produce, how much weight can each cup lift?
  • Make the cup selection per the following chart

 

Once you have selected the type and number of cups needed, you can then begin to look at which additional accessories items you might need.

  • Filters – supplying clean, dry air is key for maintaining optimal performance. An automatic drain filter  can be used to remove any water or contaminants in the supply line. If there is oil present, consider using an Oil Removal Filter.
  • Mufflers – help to reduce the noise level without restricting the airflow. We offer 2 different styles – Standard and Straight Through. Standards mufflers are a good choice where the supply air is clean and dry. These mufflers can only be used with the porous and non-porous generators. The Straight Through mufflers reduces sound levels by up to 26 dBA and are the better choice in processes where dirt or particulate may be present.
  • Tubing and Fittings – polyurethane tubing is available in 10′ sections up to 50′ for processes requiring the vacuum cups be placed in a location that wouldn’t allow for direct mounting to the NPT vacuum port on the generator or where multiple cups are needed. You want to keep the length of tubing as short as possible though for effective pickup and release time.
  • Check Valve – will maintain vacuum on the load if the supply pressure were to drop or be lost during operation.

For additional assistance selecting the proper E-Vac and accessories for your process, please contact an application engineer at 800-903-9247.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

 

Vacuum Generators: Adjustable E-Vac Holds Parts To Work Station

I’ve written before about the diversity of applications that EXAIR’s compressed air products can be used for – the Super Air Knife and the Line Vac come to mind – but of all the products in our catalog, none have a longer list of applications than the E-Vac Vacuum Generators:

While they're probably most popular for "pick and place" (as evidenced by our catalog photos) the EXAIR E-Vac's boast a wide variety of uses.
While they’re probably most popular for “pick and place” (as evidenced by our catalog photos) the EXAIR E-Vac’s boast a wide variety of uses.

I had the pleasure of helping a customer specify a product another popular application recently: clamping and chucking.  This caller had a machining center with a vacuum table – if you’re unfamiliar, it looks like an air hockey table, and works like one too, only in reverse: instead of using blowing air through all those little holes out to “float” the puck on the surface, it pulls air in through them to pull the part down and hold it in place.

This was for a relatively small table surface…about 9″ x 14″…and some of the holes could be blocked, if smaller parts were to be held down.  It was originally equipped with an electrically driven vacuum pump, but it had seen better days, and a replacement was going to be a little pricey.  They already had compressed air running to the machine, and were keenly interested in something small, inexpensive, and with no moving parts – like the Adjustable E-Vac.

After some discussion of the specs on their vacuum pump, we provided a Model 840008M Adjustable E-Vac & Muffler.  This not only gives them the ability to easily change the vacuum level & flow for different sized parts, but it also has a larger throat than the In-Line E-Vacs, meaning it won’t get clogged by the finite amount of dust & small particulate that can make it through the vacuum table’s holes.

EXAIR has four sizes of Adjustable E-Vac Vacuum Generators in stock.
EXAIR has four sizes of Adjustable E-Vac Vacuum Generators in stock.

By my count, we’ve still got fourteen E-Vac applications that I haven’t discussed in a blog yet.  If you’ve got one that you’d like to talk about (and give me something to write about,) feel free to call me anytime.

Russ Bowman
Application Engineer
EXAIR Corporation
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Can an Air Amplifier Be Used As A Vacuum Generator for a Vacuum Chuck?

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Adjustable Air Amplifier

I had a recent discussion with one of our overseas distributors whose customer buys a lot of the Air Amplifier model 6040 for another application and wanted to know if they could adapt it to a new application as a vacuum generator.

The customer’s need was to produce a vacuum of -400 mbar (-11.81” Hg) for the application. The input pressure at which they needed to produce this vacuum level was 6 BARG. The customer needed a vacuum flow of about 57 liters per minute which is not too high for us to consider.

My colleague at our distributor asked me if I could run a test to see if the model 6040 (3/4” Aluminum Adjustable Air Amplifier) could produce the needed vacuum level with 6 BARG input pressure. This is something I could do rather easily with some fixtures we already had made up in our lab. So, I set up the test and ran the Air Amplifier at 6 BARG input pressure. The unit, at its stock air gap setting was able to produce about -131 mbar(-3.87” Hg) of vacuum. I tried adjusting the input pressure and the air gap setting on the Air Amplifier. The lowest vacuum I was able to achieve was in the range of about -178 mbar (-5.26” Hg). Since this vacuum level was not close to the prescribed need, I advised my colleague of the values and told him that model 6040 would not work for this case.

And so, in the spirit of one of my favorite TV shows, Mythbusters, I then asked the question, “What would it take to produce a vacuum level of at least 400 mbar and 57 liters of vacuum flow?”. After consulting my handy dandy, new EXAIR Catalog 28 I was able to find the data I needed to resolve to a model number recommendation. My search using the data above led me to the Adjustable E-vac model 840015M which is our second smallest out of four possible models available. The designation of the “M” at the end of the model means the unit is included with a straight through muffler for sound attenuation, an all important feature for vacuum generators.

Model 840015M specifications indicate it has ability to produce vacuum flow of 114.7 liters per minute when powered at 5.5 BARG while producing a vacuum of -406 mbar (-12” Hg). This model has capacity to produce vacuum levels all the way to -847 mbar (-25” Hg) if necessary, so having plenty of head room for this recommendation to go higher will be no problem at all.

The morals of the story are: If you think you might have a crazy idea, it probably isn’t so crazy after all. If you have a scenario that you think we might be able to test with our equipment, we’ll sure give it a try if we can. Finally, new Catalog 28 is packed full of good information to help make determinations based on performance characteristics much easier so that we can make what we feel is a firm recommendation. And if we don’t think something is a viable idea or can’t be done, we will be sure to let you know that too.

Neal Raker, International Sales Manager
nealraker@exair.com

@EXAIR_NR