3 Types of Static – How Static is Generated

Static, everyone loathes it except for those kids that like to run around shocking their friends. This phenomenon affects not only everyday life with things like frizzy hair and that annoying zap you get when someone touches you but also industry. But what is static and how is it generated?

Static is generated on the atomic level from the exchange of valance electrons on each surface. The energy produced from the friction causes those valance electrons to enter an excited state; when in this excited state they begin to jump back and forth from atom to atom. When this happens, the atoms begin to accumulate either a positive charge if the atom lost electrons or a negative charge if the atom gained electrons.

As the charge accumulates on the surface where the friction occurs if a ground source (i.e., a piece of metal or a person) comes in close proximity to the charged surface an arc is generated between the two surfaces transferring the build-up of electrons and returning the charged surfaces to a neutral state.

But how can these surfaces become charged in the first place?

The most common and well-known way is via friction. Friction generation is when two surfaces rub against each other causing the static to build up on the surfaces. The energy from the two objects being pushed together and rubbing up against each other causes the electrons within the atoms to enter an excited state. When these electrons are in this excited state the valence electrons will jump from atom to another atom; this causes one atom to become positively charged (lost the electron) and the other to become negatively charged (gained the electron). The harder the two surfaces are pushed together and the faster they are rubbed together the more static will be generated.

A second type of static generation is contact static build up, which is when a charge that is built up when two surfaces impact each other and then separate. Much like friction static generation, contact static build up generates the charge on the surfaces from the kinetic energy of the impact. The material of the two objects in question will determine how many electrons are transferred from surface to surface based on the properties of the atoms in the material (Electronegativity, Ionization Energy, and Electron Affinity).

Contact Static Generation

The third type of static generation is detachment static build up. Detachment static build up once again relies on the kinetic energy and the properties of the atoms in the material. When the two surfaces are pulled apart the electrons that are transferring from one molecule to another get stuck with the molecules of one surface, which leaves both surfaces charged. This is seen a lot with plastic protective covers like the ones that come on a new window pane.

Static generation via detachment

No matter how the static is generated EXAIR’s line of Static Eliminators including EXAIR’s New Intellistat that can neutralize a 1000V charge in under one second. Don’t let static cause issues for your production facility, contact EXAIR for a solution. 

Static Eliminators

If you have any questions about compressed air systems or want more information on any of EXAIR’s products, give us a call, we have a team of Application Engineers ready to answer your questions and recommend a solution for your applications.

Cody Biehle
Application Engineer
EXAIR Corporation
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EXAIR Displays Benefits of Ion Air Gun Static Eliminators

EXAIR manufactures a range of Static Eliminator products that are all efficient, effective, and easy to use…none more so than the Gen4 Ion Air Gun. Consider:

  • It’s “plug and play,” all the way.  Connect the cable to the Power Supply, and hook it up to your compressed air system, and you’re ready to go.
  • It’s efficient and quiet.  The high velocity jet entrains an enormous amount of air from the surrounding environment, where it’s ionized and ready to eliminate static charge quickly and effectively.
  • Instant static dissipation, at your fingertips (literally) – squeeze the trigger to blow ionized air, anywhere you want (well, within the reach of the 10 foot cable, anyway.)

Model 8493 Gen4 Ion Air Gun Kit comes with everything you need, right out of the box. Just add compressed air.

Again, the Gen4 Ion Air Gun is just one of our Static Eliminator products.  How do you know if it’s the right one?  The selection of many EXAIR Intelligent Compressed Air Products comes down to the size & shape of the air flow that will solve the application.  Static Eliminators are no different.

  • If you need to treat a large surface, you might be looking for a Gen4 Super Ion Air Knife.  They come in lengths from 3 inches to 9 feet long, and blow a laminar, even curtain of ionized air that’s extremely effective and fast at static elimination, even at very low supply pressures.
  • Gen4 Super Ion Air Wipes blow a 360° ionized airstream for pipes, cables, extruded shapes, etc.
  • Gen4 Ion Air Cannons and Gen4 Ion Air Jets are made to mount in place, and blow a focused, conical flow of ionized air.

If you’ve got large areas, multiple surfaces, or complex geometries to contend with, one (or an array) of these products might be the solution.  For a simple, straightforward, hand held static elimination solution, though, it just doesn’t get any easier than the EXAIR Gen4 Ion Air Gun.  Call me to find out how you can get one today.

***Order any qualifying EXAIR Static Eliminator by February 28, 2019, and we will include a FREE AC Sensor.  Click here for details.***

Russ Bowman
Application Engineer
EXAIR Corporation
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A Tale of Two Super Ion Air Knives

A manufacturer of plastic bottles had a problem with static charge. Right after the bottles are extruded and cooled, they have an apparatus that “unscrambles” them and places them, single file, onto a conveyor. It does so with some fabric belts and plastic rollers. If you know anything of static electricity, dear reader, you probably recognize that there aren’t too many better ways to generate a static charge than to rub plastic against plastic, or (even worse) plastic & fabric together.  Here’s a prime example of the kind of static charge you can get, just from unrolling plastic film.

The separation of the non-conductive surfaces (like when this plastic film is unrolled) is capable of generating an incredible amount of static charge.

Now, the bottle makers didn’t have a static meter, but they didn’t need one to know they had issues:  the bottles that the “unscrambler” was putting on the belt were still very much “scrambled.”  They installed a Model 112209 9″ GEN4 Super Ion Air Knife Kit, to blow ionized air up from under the bottles as they entered the belt conveyor, and they did see what they’d call an improvement, but not quite what they’d call a solution.

Unfortunately, dissipating the static from just about half of the surface area of the bottle was still leaving them with half a problem.  However, by adding a Model 112009 9″ GEN4 Super Ion Air Knife (the 112209 Kit’s Power Supply has two outlets, and its Filter Separator & Pressure Regulator are capable of handling the flow to two 9″ Air Knives,) they were able to blow ionized air down from the other side, and up from where the first one was installed.  A soft “breeze” was all it took…a stronger air flow would have worked against the “unscrambler” anyway…because even at very low supply pressures, the Super Ion Air Knives produce an extremely fast static dissipation rate.

Even with a 5psig supply…which makes for just a “whisper” of air flow, the EXAIR GEN4 Super Ion Air Knife eliminates a 5kV charge in under half a second.

If you’ve got problems with static charge, we’ve not only got improvements; we’ve got solutions. Give me a call to find out how we can help.

Ion Bars Eliminate Static in Foam Web Production

10. STATIC
Foam Web with ineffective Earth grounding

Our Greek distributor came to me the other day with a production issue for one of his clients. They manufacture foam in a variety of forms for many different end uses. In this particular case, the customer was working with a flat web of foam. As they are un-rolling and processing the foam, a decent amount of static charge builds up on the material which eventually causes discharges to the rollers in the machinery and to operators as well. The discharges are dangerous to personnel as they can be quite potent, causing a reflexive jerk back which can put the operators into a dangerous position with respect to machine components, not to mention that they are just flat out uncomfortable to receive. Another issue is that the discharges also cause blemishes on the surface of the white foam where they occur. Such blemishes are considered a defect and are therefore another reason that the customer wants to investigate active static elimination.

As you can see in the above photo, the customer has a couple of ground “probes” if you will, that ride on the surface of the foam web. They do this in hopes that the charges will “drain off” to Earth ground. While this kind of “passive” static elimination can be useful in certain circumstances, many times is just not sufficient to completely neutralize the material as needed for the process. We reviewed the line speed in the application and the web was moving at a reasonably slow 10 – 15 meters per minute. With this in mind, the EXAIR Ion Bar would be a perfect fit to provide the necessary ions to “actively” discharge the electrostatic field. By actively, I mean that the ion bar produces positive and negative ozone ions which are actively delivered and come into contact with the material. This causes the net charge to drop to a much lower level than simple grounding techniques just cannot get to.

We ended up recommending two pieces of model 7042 (42” Ion Bar) (one for each side of the web and model 7907 (2 outlet Power Supply, 230 VAC input) for the application. These bars have eliminated the blemishes on the foam web and removed the static shocks experienced by the operators.

With the very coldest of winter-time temperatures upon us now, it is what we term “static season” due to the low humidity in the air. Processes like this one can be rendered hopeless without the use of some form of active static elimination.

Are you in a converting business of some kind? Do you have static issues in your processes?  If so, consider contacting us for some help with your application. Static electricity in a production environment does not have to be a problem.

Neal Raker, International Sales Manager
nealraker@exair.com
@EXAIR_NR