6″ Super Ion Air Knife Provides Separation Of Solar Panel Plates

I was recently working with a solar energy research center who was experiencing a static issue with their solar panel building process. They currently take a stack of small, silicon wafer plates, measuring approximately 6″ long X 6″ wide and 2 mm thick, and take the top plate from the stack and place it on the assembly table. The issues they were experiencing was that when they went to lift the top plate, static was making the plates cling together, resulting in several plates being picked up at one time. In some cases, they were able to get separation, but were seeing dust and dirt settle on the surface. This was causing two negative effects. First, when the plates get stuck together, they try to manually separate them which would cause them to crack or completely break. If they did get them separated without cracks, the second issue was contamination from foreign particulate would cause an operator to have to manually clean the plate, prolonging the assembly and reducing the daily production. Trying to remedy the situation, they decided to use a small open airline blowing at the side of the plates to get separation between the plates as they are lifted. While this did help a little with separation it did not remedy the particulate issue and they still weren’t able to achieve a desired result.

OLYMPUS DIGITAL CAMERA
Built Solar Panels

I recommended the customer use our Model # 111206, 6″ Super Ion Air Knife Kit in the application. The Super Ion Air Knife is our Super Air Knife with an Ionizing Bar attached to produce a laminar sheet of ionized air across the entire length of the unit. By directing the airflow at the side of the stack, the ionized air would release the static charge, allowing the individual plates to separate and as they are lifted, blow away any remaining unwanted fines on the surface of the plates. In addition, the kit includes a pressure regulator which would allow the customer to increase or decrease the supply pressure, providing some control of the exhaust air velocity and flow so they aren’t moving or disrupting the stack.

Super Ion Air Knife
Super Ion Air Knife produces uniform sheet of ionized air. Available in stocked lengths from 3″ up to 108″.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

 

Solar Panels image courtesy of Slim Dandy via Creative Commons license.

Static Returns with Colder Temperatures

The temperatures have been dipping a bit in Cincinnati.  One day it might top 80F (26C), the next it could only get up to 60F (15C).  So, its typical Cincinnati weather.

With the fluctuation in ambient temperatures comes a fluctuation in humidity and varying propensity for static.  Lower temperatures, and the corresponding aridity in the air which usually accompanies them, are prime conditions for generating static.  This is because the relative humidity (which is a percentage of moisture held in the air compared to the maximum it could hold (at a given temperature)) normally drops below 30%, which promotes static.

But why?

Lower relative humidity essentially means less moisture (water) in the air.  And, water conducts electricity very well.  So when relative humidity is above 30%, the surfaces and materials in a given environment will absorb the moisture in the air or they will form a very thin surface layer of moisture which dissipates accumulated static charges.  The thickness of the moisture layer increases with increased relative humidity, so when relative humidity drops, so does this layer on surfaces and materials.  Then, when this layer of moisture is no longer present, static can easily build up.

Such was the case for the end user in the application photos shown below.

IMG_0894
Stacked plastic sheets experiencing a static problem
IMG_0896
Additional view of plastic sheets

This system began experiencing a process disturbance when separating stacked plastic sheets.  The operation is supposed to remove a single sheet at a time, but static was causing the machine to pick up multiple units in each pass.  (Separating two insulators such as these sheets is enough to create a static charge in any environment, let alone when humidity drops and static is more prevalent.)

For this application, we recommended a set of Super Ion Air Knives with the ionized air stream aimed along the short edge of the sheets.  As the sheets begin to separate, the ionized air flow from the Super Ion Air Knife has a chance to penetrate in between the sheets and eliminate the static charge. This prevents the machine from picking up more than one sheet at a time.

As the temperatures and humidity drop it is common to experience static problems.  For help with a solution, contact an EXAIR Application Engineer.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE

Don’t Waste Your Money (or Compressed Air)

This week I worked with a customer trying to separate a 135” wide paper sheet from a fabric used for commercial paper towel machines. They were using 45 spray nozzles, spaced 3” apart on a manifold, to blow off the sheet which then would fall into a chute below. The nozzles were doing the job but they were growing more concerned with their compressed air expense for this process.

Competitor Nozzle
45 pcs. of this nozzle were replaced with EXAIR’s Super Air Knife to save $87,000 annually!

The current nozzle setup was also causing another issue – there were “empty voids or gaps” in the airflow between the nozzles, which resulted in creases in the fabric. They were considering adding more nozzles and spacing them 2” apart but that was only going to increase their compressed air expense, so I asked them to consider our Super Air Knife. They were intrigued but were concerned that they would consume more compressed air, you’ll see below that the Super Air Knife uses less air and eliminates the creasing problem because the Super Air Knife provides a continuous airflow from end to end.

After reviewing the specs, I determined that each nozzle was consuming 29.6 SCFM @ 90 PSIG of compressed air, meaning they were consuming 1,332 SCFM for the process (29.6 SCFM x 45 nozzles).

I recommended using (2) 48” and (1) 42” Aluminum Super Air Knives, coupled together, to provide a 138” laminar sheet of airflow. I chose these In Stock – Ready to Ship lengths, so the customer wouldn’t have to order a special length even though that lead time would have only been 3 days. The Super Air Knife only consumes 2.9 SCFM @ 80 PSI (per inch of knife), and provides a laminar sheet of uniform airflow with a 40:1 air amplification rate, which would not only perform in the application, but also provide the needed compressed air savings.

SAK
What a great replacement for multiple nozzle manifolds! How SAK works

Using the above air consumption for our Super Air Knife, 2.9 SCFM @ 80 PSI (per inch of knife or 2.9 SCFM x 138”), I calculated the Super Air Knife consuming 400.2 SCFM @ 80 PSIG.

Since their process is a 24 hour operation, Monday – Friday, every week of the year, I calculated the following (* Using $ 0.25 per 1000 SCF used):

  • 45 nozzles x 29.6 SCFM = 1,332 SCFM @ 90 PSIG
  • 1332 SCFM (current) – 400.2 SCFM (EXAIR proposed) = 931.8 SCFM saved
  • 931.8 SCFM x 60 minutes x $ 0.25 / 1000 SCF = $ 13.98 saved per hour
  • $ 13.98 per hour x 24 hours = $ 335.52 saved per working day
  • $ 335.52/day x 5 days = $ 1,677.60 saved per week
  • $ 1,677.60 week x 52 weeks = $ 87,235.20 in yearly savings

After reviewing this savings with the customer, they mentioned they were glad they called because they were looking at increasing their air compressor size or purchasing another auxiliary unit. Now, they were not only going to save money on their current process, but they were eliminating the need to spend major funding on another compressor – not to mention the saved compressed air being available for future growth and processes.

At EXAIR, we commit to providing our customers with solutions to optimizing their current compressed air system.

Please contact an Application Engineer for optimizing your system today.

Justin Nicholl
Application Engineer
justinnicholl@EXAIR.com
@EXAIR_JN