Stretch Wrap Static Solution

Recently a customer called in to EXAIR to discuss a static issue in a stretch wrap process in the plant. Stretch wrap is a highly stretchable plastic film.  The elastic recovery keeps the wrapped load tightly bound. The most common stretch wrap material is a linear low-density polyethylene or LLDPE.  The combination of the stretching of the plastic film and the sliding of the film on the cardboard boxes as it is being wrapped causes a build up of static. This static can cause serious havoc and issues in the process including personnel shocks, zapping counters and other sensors causing failures, and preventing marking systems from delivering good information on to the stratch wrap.

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Stretch Wrap Operation

The discussion started with minimum and maximum load sizes and how to design a system that would work with all configurations and be as flexible as possible.  We spoke of dimensions and where we could we could mount on 3 sides, and so forth.

Then came the question that we invariably get to and that is ‘what issue does the static cause and how does it affect the rest of the process?’  The answer here simple, ‘an operator has to write a code number on the side and affix a label, and in doing so, receives a shock.’ When it was determined that only a small section of one side of the load needed to be treated, the solution was simple.  We proposed an 18″ Ionizing Bar and Power Supply. Because the machine had a fixed datum, all loads would pass within 1-2″ of a vertically installed Ionizing Bar, so no adjustment is needed for different load sizes.

Ion Bar
Ionizing Bars Treating Top and Bottom Surfaces

The Ionizing Bar quickly dissipates a strong static charge as shown in the chart below.

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EXAIR offers many systems for total static control. When static is a problem on moving webs, sheet stock, three dimensional parts, extrusions or packaging, EXAIR has a solution.

To discuss your application and how an EXAIR Static Eliminator would help out, feel free to contact EXAIR and one our Application Engineers can help you determine the best solution.

Brian Bergmann
Application Engineer

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Twitter: @EXAIR_BB

Static Can Become A Big Issue With Winter Approaching

Many automotive parts are made of plastic, and with nonconductive materials, static electricity can become a big problem, especially in cooler climates.

A customer with whom I spoke recently assembles instrumentation clusters for vehicles.  The assembly process started by using a regular compressed air gun to blow the surfaces clean before assembly.  The operator would place a polycarbonate applique onto a lighting fixture.  Then a clear polycarbonate cover would go over both parts.  To complete the cluster assembly, an ultrasonic welder would weld the plastic studs around the outside edge and seal the parts together.  This completed the assembly process.  However, during inspection, they started to notice more visual defects after the welding process.  The cause was debris that became lodged between the applique and the clear cover. The debris was still present even after blowing.  If the debris wasn’t cleared prior to welding, the entire assembly would have to be scrapped due to the visual defect. The customer knew about EXAIR from previous projects and so decided to get help from us again to solve this expensive reject situation.

Initially, blowing the plastic components with regular compressed air before assembling and welding  worked well, but then they started seeing an increase in the reject rate.  I came to find out that they were located in Michigan. So I asked the customer about the weather there recently. They indicated that was getting cooler as we begin to head into Fall and Winter. As cooler weather is among us, static can be generated much easier because cool air cannot hold as much moisture. And with less moisture, which aids to eliminate a static charge, the likelihood that static will generate goes up.  Once static is generated on plastic components, dust and debris likes to stick to the surface.  Static charges are very strong, and even with blowing compressed air, the debris can still cling to edges or even “jump” to another location.  This was a manual operation and they needed to remove the static from the surface in order to eliminate the debris from the assembly.

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I recommended the model 8493 Ion Air Gun Kit. It combines static removal capability with a blowing force that one would normally associate with a compressed air blowgun.  The kit includes the Ion Air Gun, power supply, filter and regulator.  The Ion Air Gun is designed with a 5:1 amplification ratio; minimizing compressed air usage and maximizing ionized airflow.  With the regulator, you can control the force from a “blast” to a “breeze”.  The ionized airflow eliminates the static from the plastic surfaces, allowing the airstream to remove any dirt and debris.  They replaced their current air gun with the EXAIR Ion Air Gun, and the rejection rate decreased to the acceptable levels that they were seeing in the summer months.

Being that the winter months are approaching, you may want to re-evaluate your processes.  If you are working with non-conductive materials like plastic, wood, glass, or textiles, EXAIR has a variety of Static Eliminators that can save you from getting headaches, losing money, and saving time.  With our customer above, they weren’t able to get ahead of the static issue, and it created many problems until they investigated using EXAIR Static Eliminators. Get rid of your static headaches by using an EXAIR Static Eliminator today.

John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb

Static Electricity – What is it?

Now that the air is cooling and the humidity is dropping, you may often experience the phenomena of static electricity, and the resultant shock when touching something metal. As a child, you may have learned about static electricity by rubbing a balloon on your head and then seeing it stick to the wall. What is the science behind static electricity?

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All materials are made up of atoms, which have a positively charged core called the nucleus surrounded by a cloud of negatively charged electrons.  Each material is different, and in some types of materials the positive nucleus has a very strong pull on the electrons while in other materials the pull is very weak.  If we were to put a strong  pull material in contact with a weaker pull material, atoms from the weak pull material will migrate, and when the materials are separated, additional electrons will remain with the strong pull material.  Due to the overall increase in electron quantity, the material becomes negatively charged and the other material becomes positively charged. If the materials are rubbed together, the opportunities for the electron migration increases, and thus more electrons are exchanged.

Electrons build up more easily in dry conditions. When the air has humidity, static build up is less common because a very thin layer of water molecules coat most surfaces, which allows the electrons to move more freely and make most materials conductive and static free.

In some cases, static electricity can be a good thing – laser printers and photocopiers use static electricity to transfer ink from the drum to the paper.  Also, some power plants and chemical factories use static electricity  to remove pollutants in a process that takes place within the smokestack.

But generally when EXAIR gets involved, it is because the static electricity is causing an unwanted build up of static charge that affects a manufacturing process. The results of a static charge imbalance can result in a shock to an operator, materials sticking together, poor print quality, sensor or counter malfunctions, bad surface finish, or any number of other problems.

EXAIR offers systems for total static control, such as the Super Ion Air Knife and Ionizing Bars for wide applications such as paper, film and plastic webs, the Super Ion Air Wipe for narrow, continuously moving materials such as wire, tube, or extrusions.  Also offered are the handheld Ion Air Gun for use on three dimensional parts prior to assembly, packaging painting or finishing. Other options include the Ion Air Cannon for limited space or remote mounting applications, Ion Air Jet for tight spaces and concentrated airflow, and the Ionizing Point to provide close distance and accurate static removal.

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Super Ion Air Wipe

To discuss your static elimination concerns , feel free to contact EXAIR and one our  Application Engineers can help you determine the best solution.

Brian Bergmann
Application Engineer

Send me an email
Find us on the Web
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Twitter: @EXAIR_BB

Spark Photo Credit – Eric Skiff – via Creative Commons License

Changing of the Seasons

According to The Old Farmer’s Almanac, the Fall Equinox and thus the end of summer occurs tomorrow, September 22, at 10:21 am EDT for us here in Cincinnati, OH.

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Just as the seasons change and the weather goes from warm, humid days to cooler, drier times, we see a change at EXAIR in what challenges our customers face. Telephone calls and online chat topics about overheating electrical enclosures and Cabinet Cooler Systems tend to drop off and invariably the topic of static issues and the EXAIR Static Eliminators solutions take their place.

EXAIR has many available solutions for total static control, whether on a moving web, sheet stock, or three dimensional parts, extrusions or plastics.

Static eliminators with air combine EXAIR engineered airflow products with an ionizing point to eliminate a static charge quickly and at great distances.  Laminar flow air streams make it possible to blow away dirt and debris, and deliver the ionized air to neutralize surface static.  They are ideal for hard to reach places and obstructed surfaces, high speed moving objects, and surfaces with extremely high charges. Some examples are the Super Ion Air Knife, Ion Air Cannon, Ion Air Gun, and the Ion Air Jet.

Static Eliminators

Static eliminators without air may be necessary when even small amounts of air can disrupt the product, such as light weight materials. EXAIR offers two types of ionizers to handle these types of applications.  The Ionizing Bar is ideal for flat materials when the bar can be mounted close to the media.  The Ionizing Point is a good solution for spot neutralization such as in winding or slitting operations where its compact size allows for installation close to the source of the static generation. Both of these products should be mounted within 2″ of the surface they are removing static.

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Ionizing Bar

When you notice static beginning to build in your process, feel free to contact EXAIR and one our  Application Engineers can help you determine which  Static Eliminator solution can help you.

Brian Bergmann
Application Engineer

Send me an email
Find us on the Web
Like us on Facebook
Twitter: @EXAIR_BB

 

Sun and Earth Graphic courtesy of Ruslan via Creative Commons License