Volunteering Meets Engineering

We’ve shared our experiences of how EXAIR gives each employee the chance to volunteer at an organization they feel close to for an entire workday. This is a great benefit here as we get to see where each person’s interests and passions align and it sometimes gets groups of us out to spend time together doing good for others. While I’ve already used my day for the year by judging my alma maters Senior Design Tech Expo and seeing what the next generation of engineers has to offer, today I have the joy of going even further into the future generations and showcasing some garage engineering of how airflow works.

Today, I am going to be going to a Junior High School, not just any but the one my oldest attends. My best friend and I will be volunteering for their Color Run event which is a fundraiser they put on to end the year. They take a dyed powder and throw it into the air as contestants run around a field and complete various obstacles. At one of the meetings for the event, they were discussing how they went through an excessive amount of dye powder last year. They also mentioned how it didn’t work best as they had filled squeeze bottles that you would see in a restaurant with the powder to disperse as the kids come by. Well, here in Cincinnati it gets to be rather humid this time of year, so dry powder, mixed with humid air, and compression of being squeezed to disperse resulted in lots of clumping and eventually just handfuls of dye powder being dumped on kids. It also doesn’t give the big plume that they want.

1 – The Color Run, Grand Prix Edition (Melbourne 2014)

My friend and I have built a name for ourselves in the PTA as THE DADs. at the meeting, the PTA members looked at my wife who was attending, and asked if she could get THE DADs to show up for this event. Sure enough, there is no better reason to take some time off work than to douse your kid in colored powder, so we were hooked, and then the question came of, can they make this setup better. So the news came to us and we evaluated the old method. The system was simply not adapted to the scale they needed and moisture as well as the fact that some powders brick/cake when compressed wasn’t thought of. So we started brainstorming and our first thought was to take my generator and air compressor from the garage and connect a small Line Vac or even Super Air Amplifier to disperse the powder as we drop it into the entrained airflow. This setup would work, we simply don’t have the time and my generator is so loud the kids would need hearing protection. So then we looked at what we do have. I have a throw bag launcher that was constructed of an old CO2 tank and spring-loaded ball valve to get a weighted bag with a line into trees to help tie off for limb work. That is a single-shot kind of deal though, and we would be like a revolutionary war-fighter on the front line with the kids being the guerilla-like forces that don’t comply with the face-to-face combat style. So that’s out. Next, we laid out what we needed. It’s pretty simple, a large volume of air and a way to put the powder into the airflow.

Well, we both have leaf blowers, they provide a lot of air, but it is a constant flow and you can’t restrict it too much. So what can we do with a large volume of flow? Well, I happen to have a good number of PVC fittings from projects. So a good wye fitting and the leaf blower with continuous flow starts to look like a siphon-fed blow gun.

See the large volume of air will blow across the bottom of the wye fitting which will generate a low pressure on the extra leg of the wye. This gives us a draw of ambient air or in this case, an inlet port for the powder. Then the air and powder mix in the last bit of the discharge tube and voila, a plume of powder in whatever color we have on hand is created! Since I don’t have a good picture of our setup, here’s a video that helps validate our thoughts.

1 – Airbrush Inspired Leaf Blower Ball Shooter

One of the hardest things we had to do is to account for the flow of air being constant since a leaf blower that is powered does not have a quick on-off. This is one of the main benefits of using compressed air in a scenario like this, you can quickly turn it on and off to get rapid movement of air. Blowers tend to take time to spool up, like a gas leaf blower, and they don’t do well with restriction which is why some of these ball launcher designs blow the balls back up the feed tube, restriction of the barrel diameter.

While I didn’t get to use compressed air for this, I still got to use the principles that I have learned through my years here at EXAIR, and I’ll try to tweet out some images of our color plumes when I get a chance so follow my Twitter feed as well, @EXAIR_BF.

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF

1 – Chris Phutully from Australia, CC BY 2.0 https://creativecommons.org/licenses/by/2.0, via Wikimedia Commons

2 – Keith’s Test Garage, Airbrush Inspired Leav Blower Ball Shooter – retrieved from https://www.youtube.com/watch?v=oz1T70IjG4k

Static Electricity and How it is Generated

EXAIR published a white paper, Basics of Static Electricity, explaining what causes static electricity; how it is generated; and steps to eliminate it. You can download this paper HERE, and begin to remove the static issues in your plant or process.

In this blog, I would like to expand on the subject about how static can be generated.  On a molecular scale, the outer electrons that are orbiting the nucleus can be “stripped” and redistributed from one atom to another.  This will cause an electrical charge imbalance called static.  An additional electron will create negatively charged static while atoms losing an electron will create a positively charged static.  With non-conductive materials like plastic, paper, rubber, glass, etc., the electrons cannot move back to the original atom. There are three common methods of static generation that will cause this phenomenon to occur.  I will explain each one in a brief detail below:

Contact

Contact – Whenever objects hit each other, electrons can be passed to or received from the surface of another object. The number of electrons being transferred is based on the type of triboelectric material.  But, with plastic bottles or trays bumping into each other on conveyor belts, static can be generated relatively easy.

Detachment

Detachment – when one material is being separated from another material by peeling, electrons may not able to return back to the original molecule. Adhesive tape and protective films are prevalent in generating static charges by detachment because of the larger surface areas.  As an example; when the backing material is being removed from labels, the static will cause the labels to be misaligned or cause jams.

Frictional – This is one of the most common reasons for generating large static forces. It is caused by two non-conductive surfaces being rubbed together.  The amount of force being applied to the material as it slides back and forth will create higher static charges.   As an example, it is noticed when you rub a balloon on your hair.  The more times that you rub the balloon against your hair, the stronger the static forces, allowing the balloon to “stick” to the wall.  It is also noticed as sheets of material are stacked or running over rollers.

Static tends to propagate.  The more contact, detachment, and friction that occurs; the higher the static charge.  Even when the static is removed from the surface, static charges can still regenerate by the same mechanisms above.  So, controlling the static can be determined by the type of treatment as well as the location for removal.

Another variable that affects static generation is humidity.  Most process problems are noticed during the winter months as the ambient air is drier.  With a lower relative humidity, static can develop easier and with greater strength.  We always refer to winter as static season.  You may even notice this when you walk across the carpet and get zapped by touching a door handle. 

Production problems can occur like dirty surfaces, tearing, alignment, jamming and shock to staff with static.  EXAIR has a number of Static Eliminators to remove these process snags that can cost your company money.  You can contact an Application Engineer at EXAIR to discuss any static issues that are occurring.

John Ball
International Application Engineer


Email: johnball@exair.com
Twitter: @EXAIR_jb

Why – And Where – Do You Need Filtration In Your Compressed Air System?

Good engineering practice, and proper system design, call for filters at various points in a compressed air system. I’m going to go through these along the path that compressed air follows, from being drawn from atmospheric pressure in to the compressor, to being returned to atmospheric pressure at its point of use.

Any air compressor is going to have an intake filter. The small “pancake” compressor in my garage has a little disc looking thing with a screen whose mesh is about the same as my house’s window screens. Larger industrial air compressors have cartridge-type filters that impart a spiral motion to the incoming air. That motion actually removes most of the incoming particulate, while the rest gets caught in the pleats of the fiber element. The main purpose for an intake filter is to protect the compressor’s internal components. Solid particulates can really do a number on the high speed, close tolerance moving parts inside a compressor, in a hurry.

All the other filters you might find are there to ensure proper operation of the rest of your compressed air system:

  • Distribution. No intake filter is going to be 100% efficient, nor will it remove especially fine particulate that doesn’t present a real risk of damage or wear to the compressor. Intake filters also will not remove oil (or oil vapor) and water (or water vapor). The compressor itself can actually add contaminants to the compressed air, in the form of wear particles (remember those close tolerance moving parts I mentioned above?) and oil carryover. All of these contaminants will, however, be detrimental to the pipe & fittings that takes the newly compressed air to where it’s used. They can cause a buildup on the inner walls of the piping that inhibits flow. Water causes the pipe to start rusting from the inside out. When that rust scale breaks loose, it can clog, foul, or damage valves, fittings, and other control devices in the distribution header. Ideally, you’ll use filtration with a particulate element, a centrifugal element for water, and a coalescing element for oil/oil vapor (if needed…this isn’t a concern for oil-free compressors, for example).
  • Distribution, part 2. If your facility is large enough, you may need filtration at strategic locations…perhaps one for the air going to the machine shop, another for an area with machinery equipped with pneumatic cylinders, another for an assembly area where pneumatic tools are used, etc. The type(s) of filter(s) you use at those points will be determined by what the air is used for. If you know you have oil carryover from your compressor, you probably want a coalescing filter on the line to Safety Air Guns that blow off parts before painting. You don’t need them on lines going to your pneumatic tools, though…that carryover will likely help supplement the point-of-use lubricators that they use.
  • Point-of-use. Good engineering practice calls for a final stage of filtration, located as close as practical to the air operated device(s). EXAIR includes a Filter Separator with a 5 micron particulate element and a centrifugal element for water with all of our product Kits. Oil Removal Filters are also available for oil/oil vapor. They also provide additional particulate filtration to 0.03 microns.
EXAIR offers a variety of Filter Separators (left), Oil Removal Filters (middle), and Pressure Regulators (right) that are suitable for a wide range of point-of-use compressed air applications. Contact an Application Engineer for more details.

At EXAIR, we’re here to make sure you get the most out of your compressed air system. If you’d like to find out more about filtration…or any other aspect of air treatment (drying, regulating, cooling, etc.)…give me a call.

Russ Bowman, CCASS

Application Engineer
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EXAIR has Intelligent Compressed Air® Tooling

I used to work for a plastic injection molding facility that also had several different types of secondary added value processes. We used compressed air in our paint rooms, assembly areas, molding room and other various processes. I don’t recall what our compressed air usage was as we had 7 total manufacturing facilities in 5 different states. I tracked our electric bills, phone bills, water bills and all of our vending billing but, I never took the time to realize the importance and cost of compressed air.

I was successful in cost reduction activity in all those ares and so proud of the accomplishments but not once did I take the time to realize what I could save with our compressed air systems and the tooling we used with compressed air. The illustration below shows what can be saved when looking at just one air nozzle:

Compressed Air Savings

This is just one air nozzle. We used about 100 Air Nozzles, 20 paint nozzles, 50 Line Vacs and other various compressed air products. If I was able to calculate savings for all the products we used and focused on fixing air leaks in the system I would have been a real hero. Well guess what? EXAIR can help you calculate and determine the best products to help you generate these savings. We can even help you calculate your savings.

The other benefits included with EXAIR Intelligent Compressed Air® products will be the noticeable noise reduction and compliance with OSHA Standards 29 CFR-1910.95(a) Maximum Allowable Noise Exposure and 29 CFR-1910.242(b) Harmful Dead End Pressure. EXAIR meets or exceeds these OSHA Standards providing you with a peace of mind for conformance.

EXAIR has a great catalog showing our products, capabilities and performance information. Our website www.EXAIR.com offers catalog information, prices, performance, drawings, videos, blogs, air savings calculator and much more information. If you are unable to find what you need you can conveniently call one of our Application Engineers for assistance.

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