Solving Static Problem in PET Plastic Thermoforming Application

PET plastic entering thermoforming machine to make cups

The image above shows a PET plastic sheet which is fed into a thermoforming machine. During thermoforming the plastic is made into drinking cups.  But, if the plastic enters the thermoforming machine with static present, the forming process cannot occur properly which results in defects.

The company in charge of thermoforming these cups reached out to the Application Engineering department at EXAIR in search of a solution to their problem. They had considered using Ion Bars, but were unsure if Ion Bars were the right solution.  So, we examined the process and the variables at play to determine the best path forward to remove this static.

The static in this application was present throughout the travel of the plastic sheet into the thermoforming machine. At EXAIR we always recommend to install any static eliminating solution at the last possible point before the static is causing a process disturbance, to ensure no static is regenerated.  Yes, a static charge has the potential to regenerate with friction, spearation or even simple contact with another surface. In the above example separation from the roll and friction upon the additional rollers could be a source of static. This meant finding a way to eliminate the static just prior to the sheet entering the thermoforming machine.

As it turns out, the thermoforming in this application can occur between 180-260°F, and this heat permeates from the machine to the area immediately outside of the plastic feed entrance. So, placing Ion Bars just outside of the machine, while potentially possible, would place them near temperatures at the high end of their operating temperature limits (maximum temperature for an EXAIR Ion Bar is 165°F).

However, just a couple of feet away from the machine this temperature dissipates significantly. So, if we could find a way to mount our solution 2-3 feet away and effectively eliminate static, we would have a viable solution.

That solution came in the form of Super Ion Air Knives. The Super Ion Air Knives provide the same static eliminating capabilities of an Ion Bar, but with an added benefit of transferring the static eliminating ions via a smooth and laminar air profile.  This allows for us to mount the Super Ion Air Knives a few feet away from the machine entrance, but to still effectively eliminate static.  At a distance of 12” away, the Super Ion Air Knife can eliminate a 5kV static charge in 0.18 seconds at an operating pressure of 80 PSIG, and in 0.60 seconds at an operating pressure of 5 PSIG.

Based on the width of 486mm, this customer opted for (2) 18” Super Ion Air Knives, model 111018, and (1) 230VAC power supply with (2) outlets, model 7907. By installing one Super Ion Air Knife on top of the plastic sheet, and one on the bottom, the static problem in this application is solved.

If you have an application in need of a static solution, contact an EXAIR Application Engineer. We’re here to help.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR.com

Ion Air Jet Keeps Laser Scanner Lens Clean, Eliminates False Reads

An automobile manufacturer was looking for a solution to keep their laser scanner lens clean in their body welding process. The Automatic Guided Vehicles or “AGV’s” are equipped with a laser safety scanner mounted on the front and back of each vehicle, used to detect any foreign objects in it’s travel path. The scanners are fitted with a polycarbonate protective lens and as the vehicles travel through the system, the lens can build up a static charge, attracting airborne dust and particulate, which results in false readings, shutting down the line.

The current cleaning method involves an operator using a microfiber cloth to manually wipe the lenses clean, and while this does work, with the scanners being mounted roughly 4″ above the floor, this poses some ergonomic concerns for their workers. The customer found EXAIR after looking on the internet for static elimination products and it turns out, they are currently using several of our products in their facility, but he was unsure which product would be suit their needs so he reached out for assistance.

After further reviewing the application with the customer, they explained that each vehicle makes several “scheduled” stops along the route and one of these areas would be selected as the install point. I suggested the customer use (2) of our Ion Air Jet Kits, to clean the lenses. The Ion Air Jet produces a high volume of ionized airflow that can be focused right at the lenses to eliminate the static charge and carry the fines away. The kit includes a filter separator which is going to remove any condensate and/or dirt in the air supply, as well as a pressure regulator. The pressure regulator will allow them to easily adjust the supply pressure to control the outlet flow and velocity so they don’t disrupt other areas in the process.

Additionally, I suggested they use (2) of our EFC – Electronic Flow Control, which features a timing controlled (0.10 seconds to 120 hours) photoelectric sensor as a means to control air usage. As the vehicle enters the blow off area, the sensor will “see” the vehicle, signaling the solenoid valve to open the air line to the jet to blow off the lens. As the vehicle then exits the area, the sensor would again send a signal to close the air supply, so compressed air is only used when needed, reducing operating cost and further automating the process.

8494

Ion Air Jet Kit, Model # 8494 – includes the Ion Air Jet, Power Supply, Filter and Regulator

If you are experiencing static issues in your process or to see how we might be able to help with your automated system, contact an application engineer for assistance.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

 

 

EXAIR Static Eliminators Provide a Solution for a Plastic Blasting Media Application

A customer had an application where they were using a plastic blasting media (PBM) to remove a coating from composite sheets. Being that I was unfamiliar with this type of blasting media, I went to the web for research.  This process is very interesting as it can remove coatings, paint, powder coats, etc. without harming the substrate.  It is widely used in the automotive and aerospace industries as it can be used on materials like very thin metals, composites, and even hardwood.

In our experience with non-conductive materials, static can be a huge problem. And in this case, it was.  The PBM was “sticking” to everything including the composite material that was being cleaned.  They were losing material as it was leaving the blasting chamber.  As with any type of blasting system, you want to reuse the material to economically reduce waste and keep the operation running longer.  As you can see in the picture below, the PBM is clinging to the internal components because of static.  This static force was keeping the PBM attached to the composite sheet and allowing it to leave the chamber.

Inside the Plastic Blasting Media cabinet

Inside the Plastic Blasting Media cabinet

As a quick remedy, they tried to use compressed air to blow the PBM back into the cabinet. They were using copper tubes that were flattened to create a homemade nozzle.  This style of nozzle is unsafe and very loud.  It was also difficult to get the correct amount of blowing force because static can build at different rates.  The higher amount of static charges, the stronger the attraction.  They needed a better method as they found themselves wasting not only the blasting material, but also much compressed air.

With applications similar to this, we like to remove the static at the problem area. Then, we do not have to be concerned about the static forces.  For their application, the cabinet had a 6” wide opening where the composite material would exit.  So, I recommended two pieces of the model 111206, 6” Super Ion Air Knife Kits, to be mounted just outside the cabinet.  One Super Ion Air Knife would be mounted above the sheet to clean the top surface, and the other mounted below the sheet to clean the bottom surface.  I recommended that they position the Super Ion Air Knives at a 45 deg. angle to the surface of the composite sheet in the counter-flow direction.

This position will optimize the performance of the Super Ion Air Knife.  It increases the contact time to coat the surface with ions to remove the static and to keep the PBM inside the cabinet.  With the design of the EXAIR Super Ion Air Knife, it has a 40:1 amplification ratio.  That means that for every 1 part of compressed air, it will entrain 40 parts of ambient air.  So, it can operate with much less compressed air.  Once they mounted the Super ion Air Knives, they were amazed at the performance.  It was very quiet; it used very little compressed air; and it kept the composite sheets completely clean.  After the static forces are removed, it only needed a light breeze to remove the PBM from the surface.

Super Ion Air Knife

Super Ion Air Knife

If you find that static is creating process problems, wasting time, and costing you money, EXAIR has a large line of Static Eliminators that can help you. For this customer, it was a simple phone call to EXAIR that got his operation back up and running fast and smooth without static.

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

What Makes Things Easier Than An EXAIR Static Eliminator? Another EXAIR Static Eliminator!

A contract manufacturer, servicing the medical and biotechnology markets, is a long time user of our Ion Air Guns. They’ve had great success with them in keeping their products free from static & dust for years. These are mainly small, hand-held parts, so, when they need to get them clean and static-free during assembly and packaging, EXAIR’s Ion Air Gun is ideal, because it, too, is small and hand-held.

A new process, though, involves the operator needing both hands for assembly. This would mean picking up the Ion Air Gun, blowing off the part, putting it down, and then using both hands to complete the operation. They thought there had to be a better way. And they were right!

The Model 8910 Instant Static Elimination Station offers hands-free control of ionized air flow – a foot pedal turns an Ion Air Jet (whose performance is identical to the Ion Air Gun) on and off with…well, the press of a foot. The Magnetic Base and Stay Set Hose make it easy to install, and even easier to position.

Hand held convenience of the Ion Air Gun (easy) or no-hands convenience of the Ion Air Jet Station (easier.) Your call.

Hand held convenience of the Ion Air Gun (easy) or no-hands convenience of the Ion Air Jet Station (easier.) Your call.

For an even more automated approach, they are considering an EFC Electronic Flow Control. They’re ready to go, right out of the box…the photoelectric sensor will open and close a solenoid valve (installed in the compressed air supply line) based on the setting of the programmable timer unit. With a simple wave of the part in front of the sensor, the operator could activate a preset blow of a few seconds, which would be easy to determine, even easier to set, and…easiest of all…reliably repeat all day long. They’re going to try out the foot pedal first, and that’s just fine by me.  Perhaps there’s such as thing as “too easy,” but man, I hope not.

Even if you’re already using EXAIR products to make things easy, you can call me to see how much easier it might get.

Russ Bowman
Application Engineer
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Speaking of easy...get a FREE AC Sensor with a Static Eliminator order. Promotion ends 1/31/2017!

Speaking of easy…get a FREE AC Sensor with a Static Eliminator order. Promotion ends 1/31/2017!

Solving a Printing Problem with EXAIR Static Eliminators

img_5724

Unrolling plastic into this machine created a static charge throughout the process

One of the most common sources of static electricity in automated processes is friction.  As two (or more) materials move against each other, static is produced due to the triboelectric effect.  By definition, the triboelectric effect is a type of contact electrification in which certain materials become electrically charged after they come into frictional contact with a different material.  If these materials are non-conductive, or if they are not grounded, the static charge will remain.  This was the case for the machine shown above.

img_5723

Multiple stations of this machine, all experiencing static problems

This machine is a Chesnut 150 Gravure Print Station.  It is used for printing, coating, laminating, and sometimes die cutting of paper, light paperboard, films, polyester, flexible packaging and aluminum foil.

In this application, a roll of plastic is dispensed, but a static charge is preventing proper printing on the plastic as it travels from roll to roll.  As the film is separated from the roll, a static charge is produced, and this charge is carried through the process at values ranging from 3,000 – 20,000 volts.  The manager for this production area contacted EXAIR to see if there’s a viable EXAIR solution to remove this static charge.  They were interested in a solution that could eliminate static on the full width of the plastic, could be mounted 200-300mm away from the rollers, and could be replicated at multiple places along the machine.

With this in mind, the best solution was to use a series of 18” Super Ion Air Knives installed periodically along the path of plastic within the machine.  Operating at a low pressure of 1-2 BARG (14.5 – 29 PSIG), the Super Ion Air Knives create an evenly dispersed, quiet airflow of static eliminating ions with a low compressed air consumption.  Using the laminar, static eliminating airflow from the Super Ion Air Knife, this solution can be mounted away from the static charge, allowing the ions to “rain” down on the affected areas.

For this application finding a solution meant finding a method to keep production on schedule.  Without static elimination this machine faced defects, downtime, and decreased efficiency.  Using EXAIR Super Ion Air Knives brought this application back up to optimal operating speeds, keeping the revenue generating process of this manufacturer ongoing.

Colder weather is here and static comes along with it.  If you’re experiencing a static related problem in your facility, contact one of our Application Engineers.  We’d love to help you find a solution.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE

Ion Bars Eliminate Jam In Fiberglass Production

Last week I worked with a specialty glass manufacturer who was experiencing a static issue in their fiberglass mat production. Their particular production cycle consists of a rotary spinning process where molten glass exits a furnace and goes into a cylinder with several holes that rotates at high speed, causing the glass to be “pushed” through the holes. Upon exiting the cylinder, the fibers are blown down on to a conveyor belt underneath, treated with a binder and pressed together, then sent to an oven to cure. After the sheets exit the oven, they are air cooled, cut to the desired length, then sent to a sorter that directs the material to collection bins, based on thickness and length. It is at this point that they were seeing the parts start to “bunch” up, which caused the system to be shut down so an operator could manually clear the jam and sort the mats. The customer has experienced static issues before in other parts of their plant and took some readings and were seeing a 4 kV charge on the surface of the mats.

After discussing the details of the application, I recommended they use our 24″ Ionizing Bar, the width of their widest mat. The Ionizing Bars produce a high concentration of positive and negative ions to eliminate the surface static of an object when mounted within 2″ of the surface of the material. At 2″ away, the units are capable of dissipating a 5kV charge in less than half a second. By placing a unit above and below the exit point of the sorter, they would effectively remove the surface charge and eliminate the potential jam.

Ionizing Bars Work

Ionizing Bars are effective up to 2″ away and require no compressed air to operate.

Our Ionizing Bars are available in lengths from 3″ up to 108″ for a variety of small or wide surface treatment applications. For assistance selecting the best product for your specific requirements, please contact one of our application engineers at 800-903-9247.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

Solving Static Problems with EXAIR Ion Bars

pic-2

This plastic film stretching machine needed a viable static elimination solution.

The relationship between humidity and static is something we’re very familiar with at EXAIR.  As temperatures drop and humidity decreases, the reduction in moisture content within the air translates to an increase in static .  This is because higher moisture content in the air creates a surface layer of moisture that dissipates accumulated static charges.  When this surface layer disappears, static forms quickly and easily.

Fortunately, we have a full line of static eliminating equipment suitable for use in removing static related process disturbances.  For example, the photo above shows a plastic stretch wrapping machine at its dispensing point.  As the plastic is pulled from the roll static builds up quickly and this customer needed an easy, reliable solution to remove the static.  Ideally, they wanted something that would not require compressed air, but could still mount closely to the machine and remove the static charge.

The solution for this application was a series of two 24” Ion Bars mounted on each side of the film.  As the plastic is unrolled it passes through the opening created by the Ion Bars, eliminating the static charge.  The machine required no significant downtime to install this solution, and nothing within the machine setup had to be modified.

This type of setup was ideal because it treated the static at the proper point within the process, used no compressed air (as requested by the customer), and it provided a simple installation to solve the problem.

Plastic sheets and films that are being separated after full contact can generate significant static charge.  If you have a film/sheet application, or another static related need, contact an EXAIR Application Engineer.  We’d love to help you find a solution.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE

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