Thursday 19 August 2021

6 Important Factors when Choosing a Safety Air Gun


If you look at operating costs alone, compressed air can be just about the most inefficient method there is for cleaning parts. If you just look at the risks, it’s potentially very dangerous too. Don’t even get me started on the insufferable noise it can make.

For cleaning parts, most folks are familiar with the use of an air gun. You can find the simplest of these in many industrial settings: a valve (often in the form of a handheld trigger device) fitted with a nozzle of some sort (often in the form of an open ended tube, pipe, or fitting to focus or direct the air flow). These have all three of the “downsides” I opened this blog with. Of course, these concerns can be mitigated to a high degree by using the right tool for the job. That’s where engineered products like EXAIR Safety Air Guns come in. Let’s look at how we can address these three “downsides”:

Efficiency: This is all about compressed air consumption. In the simplest of air guns mentioned above, consumption is only limited by the passages in the valve (or trigger) and the discharge fitting…and those limits are usually negligible. Modifying the ends (see examples below) to focus the air flow usually has minimal effect, because you’re not appreciably changing the total cross sectional area of the discharge opening:

Here are a few modified thumb trigger air guns that were sent in for Efficiency Lab testing. Left to right, compressed air consumption at 80psig supply pressure was 34.2 SCFM, 30.9 SCFM, and 28.2 SCFM. For comparison (more on this later,) EXAIR Model 1210 Soft Grip Safety Air Gun uses only 14 SCFM and generates a very similar flow pattern.

Safety: Remember learning about kinetic and potential energy in grade school? Well, when you compress air to 100psig, fitting all that air into a much smaller space creates a TREMENDOUS amount of potential energy:

The block on the left represents a cubic foot of air at atmospheric pressure. The one on the right represents how much space the first one takes up when compressed to 100psig. The energy imparted by this process HAS to be handled with care.

One problem with the thumb guns above is, if you were to jam into the palm of your hand and pull the trigger, a large component of that potential energy (pressure) turns into kinetic energy (force)…more than enough to break the skin and cause a potentially fatal condition known as an air embolism. In the United States, OSHA (Occupational Safety and Health Administration) regulates compressed air devices used for cleaning purposes. All EXAIR Safety Air Guns comply with Standard 1910.242(b) by providing a relief path to ensure that it cannot be dead ended, and thus never create over 30psi measurable at the outlet).

EXAIR Super Air Nozzles cannot be dead ended, ensuring the outlet pressure won’t reach OSHA limits, regardless of supply pressure.

Noise: Another problem is, another component is turned into sound pressure…discharging air from a direct opening is quite loud. OSHA standards address these with limitations on outlet pressure and sound level. All EXAIR Safety Air Guns comply with Standard 1910.242(b), which limits the outlet pressure (by providing a relief path to ensure that it cannot be dead ended, and thus never create over 30psi measurable at the outlet) and all but our largest Super Blast Safety Air Guns comply with Standard 1910.95(a) limits for continuous 8 hour sound level exposure.

Which brings us to the topic of this blog: How exactly did THEY (our customer who used to use the thumb guns above) select the right Safety Air Gun, and how can we apply that to getting the right Safety Air Gun for YOU?

These steps aren’t all-inclusive, and they don’t necessarily need to be followed in order, but if you call an EXAIR Application Engineer about selecting a Safety Air Gun, here’s what we’re gonna talk about:

Ergonomics: We offer five distinctive styles of Safety Air Guns:

From small part cleaning by hand, to wide area blowoff, and all points in between, EXAIR has a Safety Air Gun for most any application.

Our thumb gun user (as I alluded to above) chose the Model 1210 Soft Grip Safety Air Guns (top right). They had a number of typical industrial applications where the operators had the parts or surfaces to be blown off right in front of them. They liked the integral storage hook and rubberized hand grip, but the VariBlast Compact (top middle) or Heavy Duty Safety Air Guns (bottom left) were also considered. The VariBlast Precision (top left) and Super Blast Safety Air Guns (bottom right) were too focused or more powerful, respectively, than needed.

Airflow pattern: Honestly, I could make a good case for this being the first consideration. Selection of any blowoff product – be it an Air NozzleAir AmplifierAir KnifeAir Wipe, etc., will largely depend on the size and shape of the airflow.

    variety of airflow patterns…and effective distances…are available from EXAIR’s comprehensive line of Super Air Nozzle products.
    • For the most precise, focused blowoff, our Atto Super Air Nozzle (top left) is a great choice. It’s available on:
      • VariBlast Precision Safety Air Gun
      • VariBlast Compact Safety Air Gun
      • Soft Grip Safety Air Gun
    • For the typical industrial blowoff applications our thumb gun user had, the Model 1100 Super Air Nozzle (top right) comes on:
      • Soft Grip Safety Air Gun
      • Heavy Duty Safety Air Gun
    • Super Air Nozzle Clusters (bottom left) create higher force & flow, and still keep it in a more concentrated, tighter pattern. They can be installed on:
      • Soft Grip & Heavy Duty Safety Air Guns (4-Nozzle Cluster only)
      • Super Blast Safety Air Gun
    • When stubborn, heavy, and/or LOTS of debris needs to be absolutely, positively blown off RIGHT NOW, our High Force Super Air Nozzles may be just what you need. Our largest; Model 1120 1-1/4 NPT Super Air Nozzle, is shown (above right). The High Force Super Air Nozzles are offered on:
      • Soft Grip or Heavy Duty Safety Air Gun (up to 3.3 pounds of force over a 6.3″ wide area @12″ away)
      • Super Blast Safety Air Gun (up to 23 pounds of force over a 15″ wide area @12″ away)

    Application specific concerns: Everything we’ve discussed so far has involved aiming the blow off stream away from the operator, in the direction the device is aimed. In addition to wide variety of engineered Air Nozzles, EXAIR offers a number of options for these products:

    • We can add 12″ or 20″ extensions, and/or Chip Shields, to our VariBlast Precision Safety Air Guns.
    • VariBlast Compact Safety Air Guns can likewise be fitted with Chip Shields, as well as:
      • Rigid extensions, up to 72″ long.
      • Our Atto Back Blow Nozzles, with extensions up to 36″ long.
    Atto Back Blow Nozzles can blow out recesses or holes as small as 1/4″ in diameter.
    • Soft Grip Safety Air Guns are the most versatile, as far as options go. In addition to Chip Shields, we also offer:
      • Rigid Extensions, up to 72″ long.
      • Stay Set Hoses, for blowoff in hard to reach areas or spaces, in lengths from 6″ to 36″.
      • Back Blow Nozzles for holes with 7/8″ to 4″ diameters, on extensions up to 72″ long.
      • Super Air Scrapers, with extensions from 6″ to 72″ in length.
      • Scrape off, and blow away, stubborn debris with the Model 1244-48 Soft Grip Super Air Scraper.
        • Heavy Duty Safety Air Guns can be fitted with Chip Shields, Rigid Extensions (up to 72″ long) and Back Blow Nozzles as well.
        • We can add 3 foot or 6 foot extensions to our Super Blast Safety Air Guns for extra reach, when necessary.

        If you’re looking for a portable, hand-held compressed air blow off product that’s quiet, safe, and efficient, look no further than EXAIR Corporation’s extensive line of Safety Air Guns. If you’d like to find out more, Contact us.

    Vivek Engineers
    #22, 1st Floor, 1st Cross, Adj. to IIMB Compound, Bilekahalli Indl. Area, 
    Bannerghatta Road, Bangalore - 560 076 
    Ph : 080 -  2648 1309, 4170 1145.
    Mob : 097404 39220


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