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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Air Nozzles and Air Jets: An Overview

One of the simplest solutions to lower your air consumption and noise level when it comes to compressed air is to switch your open tubes or pipes and liquid nozzles which are being used for air applications to an engineered compressed air nozzle. EXAIR’s Engineered Air Nozzles and Jets provide a simple solution for a wide variety blow off and compressed air applications and can solve a multitude of process problems efficiently. These applications can include simple blow offs, cooling, part ejection, and much more.

Super Air Nozzles:
Super Air Nozzles are one of the more versatile of all of EXAIR’s Engineered Air Nozzles. They come in many different sizes from a tiny size of M4 threads and 13 millimeters long to the largest with  1-1/4 NPT threads which has a 2″ hex and is almost 5″ long. These are usually used for standard blow off applications that replace open pipes to reduce your air consumption and noise. The force values vary from 2 ounces to 23 pounds of force. 

Another variation of the Super Air Nozzles is the Flat Super Air Nozzles; these nozzles create a small flat curtain of air at a high force to provide a wider blow off area for smaller NPT sized nozzles. The 1” and 2” Flat Super Air Nozzle also have replaceable shims that allow you to adjust the force coming out of the nozzle by increasing the amount of air that is used.   

EXAIR Air Nozzles

Back Blow Air Nozzles:
Back Blow Air Nozzles are designed in a way that blows that makes it easy to blow out the inside of pipes. The Back Blow Air Nozzles have holes around the outside diameter pointed back that creates a cone of air around the air inlet port. This makes it easy to dislodge clogs in pipes that you don’t want going back into the machine and for blowing out liquid and debris from the inside. They are also commonly used with EXAIR’s Chip Shield as to prevent any particles from flying back and hitting the user. Back Blow Air Nozzles come in three sizes: M4, ¼”, and 1” and can be used on inside diameters ranging from ¼” to 16”. 

EXAIR Back Blow Air Nozzles

Super Air Nozzle Clusters:
Super Air Nozzle Clusters use a number of the ¼” Super Air Nozzles to create one nozzle that has a wider cone and larger force. Clusters are usually used in wide area blow off but can also be used for part cooling and part reject as they do supply a wider area of force. Super Air Nozzle Clusters are sized by the number of nozzles in the cluster; the three sizes that we offer are 4-nozzle cluster (3/8” NPT inlet), 7-nozzle cluster (1/2” NPT inlet), and the 12-nozzle cluster (1” NPT inlet). 

EXAIR Super Air Nozzle Cluster

Air Jets:
Air Jets amplify the total volume of air into a high velocity stream of air. This makes it very useful for blowing off/drying applications and cooling applications due to the higher volume of air flowing through the unit. Air Jets come in two variations which are the High Velocity Air Jet and the Adjustable Air Jets. The High Velocity Air Jet uses a 0.015” shim that allows the air to escape the unit at a high velocity laminar flow to entrain the surrounding ambient air; this can be adjusted down using the shim kit which includes a 0.006” and 0.009” shims. The Adjustable Air Jet allows the user to easily adjust the air gap using the micrometer gap indicator. 

EXAIR Air Jets

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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The Impressive ROI of an Engineered Air Nozzle

You may have asked…why should I switch over to an engineered air nozzle if my system already works? Or…How can air nozzles be much different?

Manufacturing has always been an advocate for cost savings, where they even have job positions solely focused on cost savings. Return on Investment (ROI) is a metric they look toward to help make good decisions for cost savings.  The term is used to determine the financial benefits associated with the use of more efficient products or processes compared to what you are currently using. This is like looking at your homes heating costs and then changing out to energy efficient windows and better insulation. The upfront cost might be high but the amount of money you will save over time is worth it.

Model 1100 Super Air Nozzles can save compressed air dollars and increase safety

But how is ROI calculated? It is very simple to calculate out your potential savings of using one of EXAIR’s Intelligent Engineered Compressed Air Products. If you would rather not do the calculations out yourself then we can do it for you by sending the item in question to our Efficiency Lab Testing. The Efficiency Lab Testing is a free service that we offer to show you the possible savings by switching to one of our products.

The following is a simple ROI  calculation for replacing open blowoffs with an EXAIR Super Air Nozzle:

  • ¼” Copper Pipe consumes 33 SCFM at 80 psig (denoted below as CP)
  • A Model 1100 ¼” Super Air Nozzle can be used to replace and only uses 14 SCFM at 80 psig (denoted below as EP)

Calculation:

(CP air consumption) * (60 min/hr) * (8 hr/day) * (5 days/week) * (52 weeks/year) = SCF used per year for Copper Pipe  

(33) * (60) * (8) * (5) * (52) = 4,118,400 SCF

(EP air consumption) * (60 min/hr) * (8 hr/day) * (5 days/week) * (52 weeks/year) = SCF used per year for EXAIR Product  

               (14) * (60) * (8) * (5) * (52) = 1,747,200 SCF

Air Savings:

SCF used per year for Copper Pipe – SCF used per year for EXAIR Product = SCF Savings

               4,118,400 SCF – 1,747,200 SCF = 2,371,200 SCF in savings

If you know the facilities cost to generate 1,000 SCF of compressed air you can calculate out how much this will cost you would save. If not, you can us $0.25 to generate 1,000 SCF which is the value used by the U.S. Department of Energy to estimate costs.

Yearly Savings:

                (SCF Saved) * (Cost / 1000 SCF) = Yearly Savings

                                (2,371,200 SCF) * ($0.25 / 1000 SCF) = $592.80 annual Savings

With the simple investment of $42 (as of date published) you can calculate out the time it will take to pay off the unit.

Time Until payoff:

                (Yearly Savings) / (5 days/week * 52 weeks/year) = Daily Savings

                                ($592.80/year) / (5 days/week * 52 weeks/year) = $2.28 per day

                (Cost of EXAIR Unit) / (Daily Savings) = Days until product has been paid off

                                ($42) / ($2.28/day) = 17.9 days  

As you can see it doesn’t have to take long for the nozzle to pay for itself, and then continue to contribute toward your bottom line. 

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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What Makes EXAIR’s Super Air Knife so Efficient

EXAIR Super Air Knives have been designed to improve upon performance characteristics of our original Standard Air Knife design, which was already a very good performer itself. The Super Air Knife design improves air consumption and noise exposure levels. Since they use less air, they cost less to operate. Because they operate quieter, they can contribute to a quieter environment and increase safety for your personnel. 

Compressed air is such a common utility in manufacturing environments (and more) that many of us take it for granted and may not be the best stewards of its use.  EXAIR Super Air Knives are the most efficient compressed air knife on the market today and help us all to use our compressed air more wisely.

If you have homemade air knives, pipe with drilled holes or manifolds with multiple nozzles, you are in a position to play the hero and save your company compressed air and money. 

Implementing a design which uses the free air surrounding us all, is a significant feature making the Super Air Knife efficient. This is done by utilizing entrainment to move the surrounding ambient air and amplify the blast of compressed air.

Diagram showing how the Super Air Knife works

Air Entrainment is the phenomenon that occurs when air/gas under pressure is released from a device in such a way that a low pressure is generated in the immediate area of the gas discharge.  Gas from the surrounding environment is then pulled into the discharged air stream, increasing its volumetric flow rate. Using this principle, a Super Air Knife increases the air flow without increasing the amount of compressed air used.

This phenomenon is prevalent in many of EXAIR’s products but shines the brightest with EXAIR’s Super Air Knife. The Super Air Knife Sports the highest entrainment ratio out of all of the products with a whopping 40:1 ratio, this makes for a very efficient use of compressed air. With an air consumption of only 2.9 SCFM per inch of air curtain at 80 psig then the air knife would be moving 116 SCFM per inch of air curtain. That’s a lot of air!

Also the fact that entraining ambient air is just moving the ambient air with the energy within compressed air makes process is extremely quiet. This is because the outer layers of the total developed flow are lower in velocity, and serve as a sound-attenuating boundary layer.  The sound level of a Super Air Knife at any length is only 69dBA.  That’s about as loud as someone talking at normal speech 3’ away from you.

Entrainment demonstration using a Super Air Knife

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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Follow me on Twitter
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