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
Visit us on the Web
Follow me on Twitter
Like us on Facebook

These Nozzles Clean Blind Holes, Pipe Inside Diameters, Tube, Channels and More

EXAIR manufactures a variety of Air Nozzles and Jets . Back Blow Air Nozzles can help reduce cost, clean hard to get to areas in small diameters, pipes, tubes, channels and holes. These nozzles are designed to remove debris from pipes, blind holes, and other areas where it is difficult be effective. Sometimes it is a bad idea to blow debris all the way through a pipe because there may be personnel on the other end or it is simply too long or it may be sealed on an end. 

The Model 1006SS cleans metal shavings from inside a pipe.

The Back Blow Air Nozzles are all made from 316 Stainless Steel with three sizes as outlined below:

Model 1004SS: This is a M4 x 0.5 and delivers the smallest, most effective airflow for cleaning out small diameter tubes, pipes, channels or holes for diameters between 1/4″ up to 1″. Extension pipes available from 6″ up to 36″ in length.

Model 1006SS: The 1/4 NPT Back Blow Nozzle recommended for a wide range of diameters from 7/8″ up too 4″. Extension pipes available from 12″ up to 72″ in length.

Model 1008SS: 1 NPT female and the largest Back Blow Nozzle in stock for diameters from 2″ up to 16″ with pip extensions available from 12″ up to 72″ long.

Model 1306SS-6-CS Heavy Duty Safety Air Gun with 6″ extension and chip shield

These nozzles can also be assembled to our VariBlast, Soft Grip, Heavy Duty and Super Blast Safety Air Guns. EXAIR safety air gun options include chip shields and pipe extensions up to 72″ long. EXAIR has the products and accessories you need to make any job more efficient saving you time and money. Give us call at 800.903.9247 and ask for any of our qualified Application Engineers to help you. Most items are stock and can be shipped the same day if we receive and enter your order by 3:00PM EDT.

Eric Kuhnash
Application Engineer
E-mail: EricKuhnash@exair.com
Twitter: Twitter: @EXAIR_EK

Considerations for Ejecting Parts with an Air Nozzle: Weight and Friction

I had a customer wanting to reject a container off a conveyor belt.  The container held yogurt, and when an optic detected a reject, they wanted to operate a solenoid to have a nozzle blow the container into a reject bin.  They had a range that went from 4 oz. (113 grams) for the small containers to 27 oz (766 grams) for the large.  He wanted me to suggest one nozzle for all sizes, as they would automatically regulate the pressure for the full range of products.  In looking at the largest size, this container will need the most force to blow off the conveyor.  The two factors that affects the force in this type of application is weight and friction.  When it comes to friction, it is generally an unknown for customers.  So, I was able to help with a couple of things to determine the friction force.

Friction is a dimensionless number that represents the resistance created between two surfaces.  We have two types; static friction, ms, and kinetic friction, mk.  Static friction is the maximum amount of resistance before the object begins to move or slide.  Kinetic friction is the amount of resistance that is created when the object is moving or sliding.  So, Static friction is always greater than kinetic friction, ms > mk.  For this application, we will use an air nozzle to “shoot” horizontally to hit the rejected product.

Let’s take look at our customer’s application.  We have a system to reject a non-conforming part with air.  The conveyor has a urethane belt.  The container is plastic.  For the largest container, they have a weight of 27 oz. (766 grams).  Being that the conveyor belt is only 12” (30.5 cm) wide, we can determine that if we get the part moving, it will continue off the belt and into the reject bin.  The equation for the maximum amount of force required to move a container is below as Equation 1.

Equation 1

Fs = ms * W

Fs – Static Force in ounces (grams)

m– Static Friction

W – Weight in ounces (grams)

One way to determine the amount of force is to use a scale similar to a fish scale.  The scale should have a maximum indicator to help capture the maximum amount of force.  You will have to place the object on the same belt material because different types of materials will create different static forces. Keep the scale perpendicular to the object, and slowly pull on the scale.  Once the part begins to move, record the scale reading.  For the exercise above, it showed 9.6 oz. (271 grams) of force to move the 27 oz. (766 gram) object.

Another way would be to calculate the static friction, ms.  Static friction can be found by the angle at which an object starts to move.  By placing the container on a section of supported urethane conveyor belt, you can lift one end until the object starts to slide.  The height of the lift can be measured as an angle.  As an example, we take 3 feet (0.9 meter) of supported urethane conveyor belt, and we lifted one end to a height of 1 foot (0.3 meters) before the 27 oz (766 gram) container moved.  To determine static friction, it is the tangent of that angle that you lifted.  With some right triangle trigonometry equations, we get an angle of 19.5o.  Thus, ms = tanq or ms = tan(19.5o) = 0.354.  If we plug this into Equation 1, we get the following:

Imperial Units                                                    SI Units

Fs = ms * W                                                         Fs = ms * W

= 0.354 * 27 oz.                                                = 0.354 * 766 grams

= 9.6 oz. of force                                              = 271 grams of force

1″ Flat Super Air Nozzles

Now that we have the static force, we want to be slightly higher than that.  In looking at the force requirements that are published in the EXAIR catalog, it shows that the model 1126 1” Super Flat Air Nozzle has a 9.8 oz. (278 grams) of force at 80 PSIG (5.5 Bar).  This force is measured at a 12” (30.5 cm) distance with a patented .015” (0.38mm) shim.  So, this nozzle will be able to slide the largest container into the reject bin.

1″ Flat Super Air Nozzle shims

To expand on the benefits in using the EXAIR Flat Super Air Nozzles, the force can be changed easily with a regulator or with a Shim Set.  This is a unique feature as most competitive flat nozzles do not allow you to do this.  The patented shims control the force rating in a wide range with lower air consumption and lower noise levels; making them safe and efficient.  So, if this manufacturer decided to produce other sizes in the future, then they could change the shim to target even larger containers.  The flexibility of using the EXAIR Flat Super Air Nozzles allow you to increase or decrease the force by just removing two screws and changing the thickness of the shim inside.  EXAIR does offer a pack of shims with different thicknesses which are called a Shim Set.

With air pressure or shim manipulation, the customer could use the same nozzle for the yogurt containers.  If you have any applications that need products to be rejected quickly, an Application Engineers at EXAIR will be happy to help you with a solution.

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

Photo: Yogurt by BUMIPUTRAPixabay Licence

EXAIR Celebrates Manufacturing Day With A Win For A Manufacturer

In 2012, the National Association of Manufacturers organized an effort to proclaim the first Friday in October (hey, that’s today!) as Manufacturing Day.  According to the Advanced Manufacturing National Program Office (a division of NIST, the National Institute of Standards & Testing,) the purpose of MFG Day is “to raise awareness among students, parents, educators and the general public about modern manufacturing and the rewarding careers available.”

Today is kind of a big deal around here.  Not only is EXAIR Corporation a manufacturer, but many of the companies that use our products are as well.  A lot of us have a rich story, woven into the cloth of the history of American manufacturing (which, in turn, is woven into the larger cloth of American history.)  Have you heard the one about the motivated inventor with an idea to make innovative products who started an operation out of his home that, with inspired direction & vision, became a worldwide leader in their industry?

Yeah; that’s us.  Today, we’re honoring Roy Sweeney’s legacy (he founded the company in October 1983,) and celebrating MFG Day, by publishing a new Case Study, proving out the benefits of the use of EXAIR Intelligent Compressed Air Products in regard to the monetary savings associated with the reduction in compressed air use, and the noise level reduction from the implementation of our engineered products.

You can download the complete Case Study here, but while we’re on the subject, here’s a basic rundown:

  • A roll forming operation used to blow off their product with a combination of loud and inefficient devices: copper tubing and modular flexible hose which is designed primarily for machine tool coolant, but often misapplied for use with compressed air.
  • It worked just fine, but an engineering study noted it as a potential wasteful use of compressed air.  That’s when they called us.
  • By replacing those blow offs with Model 1100 Super Air Nozzles and Model 1122 2″ Flat Super Air Nozzles, their noise levels dropped from 107 dBA to 83.8 dBA.  To put that in perspective, it went from the approximate sound level of a rock concert to that of a leaf blower. (ref: Centers for Disease Control & Prevention: What Causes Hearing Loss?)
  • Compressed air consumption dropped by more than half, from 190 SCFM to 86.8 SCFM…an annual savings of over $3,200.00.  All for an investment of $654.00 (2020 pricing) for those engineered Air Nozzles, Stay Set Hoses, and Magnetic Bases.  That means they’ll have paid for themselves in just under two months.
  • In addition to that, for participation in this Case Study, we’re giving them a generous credit on their order.  Happy Manufacturing Day!

And frankly, I think the engineered products just look better too.

Last but certainly not least, this reduction in compressed air usage decreases the load on their air compressors, reducing the electrical power consumed.  Product impact, along with our own consumption of resources and waste recycling, is a key component of EXAIR Corporation’s Sustainability Plan.  We’re making the world a better place, by making products that make the world a better place, using methods that make the world a better place.  I can’t think of a better way to celebrate Manufacturing Day.  If you want to get in on it, give me a call.

Russ Bowman
Application Engineer
EXAIR Corporation
Visit us on the Web
Follow me on Twitter
Like us on Facebook

 

 

 

MFG Day logo courtesy of nist.gov