EXAIR Super Air Wipe Greatly Increases Productivity & Saves Money!

Late last year I received a call from a customer that was using EXAIR Super Air Knives to create an air curtain that protected the lens on their Robotic Welders from weld spatter.  The EXAIR Super Air Knife accomplished this by virtue of its design to deliver a uniform sheet of laminar air flow across its entire length.  While this greatly improved the life of the welder lens and reduced maintenance time, further improvements were needed.

The event that triggered this was the challenge they received from their customer (one of the big 3 automobile manufacturers) to increase their output of welded seat frames by 50%.  While the EXAIR Super Air Knives greatly reduced lens maintenance the consensus was further improvements would facilitate the goal of increasing output 50% .

Super Air Knife laser application
Using the Super Air Knife to protect the welding lens

 

This started the discussion on the possibility of using the EXAIR Super Air Wipe, even though it is primarily used for drying/cleaning of long continuous flow products its airflow pattern (see illustration below) was able to direct the weld splatter down and away from the lens.  This ultimately proved to be more effective at protecting the lens than the laminar air curtain provided by the EXAIR Super Air Knife.

Air Wipe - how it works
Air Wipe – How it work

The installation of the EXAIR Super Air Wipes started on 12/16/2017 and was completed on 12/23/2017. The original production rate was 480 pair of SUV rear seat frames per day running 3 shifts 24/6.

Laser Above SAW Front
Robotic Welder fitted with EXAIR Super Air Wipe

After the Installation of the EXAIR Super Air Wipes, they had improved the production rate to 750 pair/day running 3 shifts 24/5 days per week.  That equates to a productivity increase of 156%, far exceeding the goal of 50%!

Before using the EXAIR Super Air Wipe their maintenance department would clean the Cover Slide on the Laser Welding Head – 3 times per day at approximately 20 min x 3x daily x 6 days / week 6 hours / week.  “With the EXAIR Super Air Wipe we found that we can weld for 10 days before cleaning the Cover Slide” says the customer.

Each Cover Slide costs $195 and those were being replaced weekly, it was a pleasant surprise to find out that only a small amount of dust collects on the Cover Slide now, which is cleaned off in less than a minute

In 10 weeks of Operation they have not replaced a single  Slide since the EXAIR Super Air Wipe has nearly eliminated pitting from the weld spatter.

Also, Cleaning of the Slides is now performed on Saturday’s at the leisure of the maintenance team and not under the strain of production time. The Labor Rate for Maintenance is $75/hour x 6 hours/week = $450 X 50 weeks/year $22,500 plus the cost of the replacement windows at $195 each x 25 weeks = $4,875 savings per year.  Total savings after implementing the EXAIR Super Air Wipe = $27,375 per welding machine!

With the maintenance & replacement cost savings alone it is an easy calculation to make on the purchase of the EXAIR Super Air Wipe’s. That figure is not counting the productivity increase of 156% which allowed them to meet their customers delivery schedule and reduce overtime!

If you would like to discuss increasing the efficiency of your compressed air usage, quieter compressed air products and/or any EXAIR product,  I would enjoy hearing from you…give me a call.

Steve Harrison
Application Engineer
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Turn The Pressure Down & Save Money

In the past your typical industrial air compressor was rated to run at 100 psi and it was not often that this pressure was exceeded.  Lately with modern advances pressures have slowly crept up and have surpassed this threshold.  Unfortunately this has proven costly to the industrial user of compressed air.

To clarify this point, if a compressed air system is set to maintain 102 psi it will cost the plant 1% more in electric costs than if the system ran at 100 psi.  Also noteworthy is that unregulated air demands consume about 1% more flow for every psi of additional pressure.

So why is the air pressure getting so high and what can you do about it?  Here are some possible causes and solutions:

Devices that do require more than 100 psi:  It may not be the pneumatic device at all. If these devices are connected with restrictive fittings or there are excessive leaks in the system this can cause up to a 30 psi increase in line pressure just to make up for the poor piping. If this can be corrected it is possible that the pressure can be reduced.

EXAIR offers the Ultrasonic Leak Detector to facilitate tracking down hard to find system leaks and a wide variety of Air KnivesAir Amplifiers, Super Air Wipes, Air Nozzles, Line Vacs, Vacuum Generators and all of them are engineered to provide peak performance at 80 psi and make efficient use of compressed air. Though it is not uncommon for these products to provide a solution at much less pressure.

9061
EXAIR 9061, Ultrasonic Leak Detector

Applications that are believed to be high pressure:  Plant workers sometimes think that a higher air pressure is required than actually necessary.  This can be caused by a lack of training or perhaps the trainers are simply repeating what they have been taught in error.  It is good practice to review all locations that are using a higher pressure to determine if it is really necessary.

Loss due to undersize pipes:  If your plants compressed air supply lines are undersized for the volume demand, this can cause a significant restriction and raise the line pressure.  The EXAIR Digital Flow Meter can assist in recording how much demand is for a given point in time which will clarify usage.

9093
EXAIR Digital Flow Meter

 

Filter/Dryer restrictions:  If the Dryer or Filter/Separators are dirty and/or undersized the compressor operating pressure is typically raised to overcome these restrictions.  EXAIR has six sizes of Filter/Separators to ensure they are properly sized for the SCFM required by the devices that are connected to them.  Five of the models feature an automatic drain system and of course we carry the replacement filter elements and rebuild kits to keep them in top operating condition.

Temporary demands: There may be occasional peak compressed air demands in the plant that may be caused by a different or special compressed air process or machine. If the demand is greater than the supply, the pressure may be pulled down to unacceptably low levels.  In an attempt to make up for the increased demand a plant may raise the operating pressures.  The best way to cope with temporary demands is to install a receiver tank that stores compressed air that can be released when the demand calls for it.

receiver_tank
EXAIR 9500-60, 60 Gallon Receiver Tank

Factory default settings:  It is common for compressor manufacturers to set the air pressure at or very near the maximum pressure rating for that compressor.  There is no reason for this other than to verify that the air compressor will perform at its rated maximum pressure.  To save on air and maintenance costs the compressor should be set only as high as the maximum pressure for approved uses in the facility.

In the compressed air industry, EXAIR provides tools and products with quick payback times.

If you would like to discuss increasing the efficiency of your compressed air usage, quieter compressed air products and/or any EXAIR product,  I would enjoy hearing from you…give me a call.

Steve Harrison
Application Engineer
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Heat Recovery from an Air Compressor

On the whole most of us are quite aware of the considerable savings that can be accomplished by wise use and recovery of energy.   One way that a plant can save substantially is to capture the energy that an electric motor adds to the compressed air from the air compressor.  As much as 80% to 93% of the electrical energy used by an industrial air compressor is converted to heat.  A properly designed heat recovery system can capture anywhere between 50% to 90% of this energy and convert it to useful energy.

The heat recovered is sufficient in most cases to use in supplemental ways such as heating water and space heating, however generally there is not enough energy to produce steam directly.

IngersollRand_R-series-R110
Ingersoll Rand Rotary Screw Compressor

 

Packaged air cooled rotary screw compressor lend themselves easily to heat recovery, supplemental heating or other hot air uses very well due to their enclosed design.  Since ambient air is directed across the compressors aftercooler and lubricant cooler where the heat can be easily collected from both the compressed air and the lubricant.

Packaged coolers are normally enclosed cabinets that feature integral heat exchangers and fans.  This type of system only needs ducting and an additional fan to minimize back pressure on the air compressors cooling fan.  This arrangement can be controlled with a simple thermostat operated vent on a hinge and when the extra heat is not required it can be ducted outside the facility.

The recovered energy can be used for space heating, industrial drying, preheating aspirated air for oil burners or  other applications requiring warm air.  Typically there is approximately 50,000 Btu/Hr of energy available from each 100 SCFM of capacity (at full load).  The temperature differential is somewhere between 30°F – 40°F above the air inlet temperature and the recovery efficiency is commonly found to be 80% – 90%.

We all know the old saying there is “no free lunch” and that principle applies here.  If the supply air is not from outside the plant a drop in the static pressure could occur in the compressor cabinet thereby reducing the efficiency of the compressor.  If you choose to use outside air for makeup, you might need some return air to keep the air above freezing to avoid compressor damage.

Heat recovery is generally not utilized with water cooled compressors since an extra stage of heat exchange is required and the efficiency of recovering that heat is normally in the 50% – 60% range.

To calculate annual energy savings:

Energy Savings (Btu/Yr) = 0.80 * compressor bhp * 2,545 Btu/bhp-hour * hours of operation.

If we consider a 50 HP compressor:

.080 * 50bhp * 2,545 Btu/bhp-hour * 2080 hrs/year =  211,744,000 Btu/yr

Where 0.80 is the recoverable heat as a percentage of the units output, 2,545 is the conversion factor.

Cost savings in dollars per year = [(energy savings in Btu/yr)/Btu/fuel) x ($/unit fuel)]/primary heater efficiency.

If you would like to discuss saving money by reducing compressed air demand and/or any EXAIR product,  I would enjoy hearing from you…give me a call.

Steve Harrison
Application Engineer
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Photo courtesy of CC BY 3.0, https://en.wikipedia.org/w/index.php?curid=32093890

 

 

Celebrate Earth Day 2018!

Earth Day is one of those days not everyone is aware happens, even with all of the news and notable facts about our resources and pollution. EXAIR is committed to raising awareness of Earth Day and encourages everyone to find an activity which produces action in the spirit of Earth Day. For example, could you help clean up a riverbank in your town, or plant some trees in a park, or recycle your household plastic/glass/aluminum/cardboard? The Earth Day website has a bunch of great suggestions for you to make a difference.

Volunteers help cleanup

At my home, we recycle our glass, metal, plastic and cardboard. At EXAIR we continue to make progress in reducing our overall footprint as well.

Sunday, April 22nd marks the 48th annual Earth Day and it will be observed in 192 countries. For EXAIR, this year marks our 35th year helping compressed air users save compressed air energy and electrical resources. It is also another year that we continue to focus on manufacturing our products with minimal impact and doing our part to help protect our planet. We are proud to manufacture efficient products, implement processes and programs throughout our facility to help use our resources wisely and recycle everything we possibly can.

First and foremost, we manufacture and sell Intelligent Compressed Air Products that are specifically designed to reduce the use of compressed air throughout facilities. On top of that, when you purchase an EXAIR product it will arrive in fully recyclable packaging and, in most cases, is made from a material that will be recyclable should it reach a point it is no longer useful.

In the past year we have improved the efficiency of our computers and computer servers which require fewer Kilowatt hours (KWH) per day . We have been able to reduce KWH/day by over 56%! This reduces our impact on the local electricity provider and further shrinks our impact upon precious resources.

EXAIR recycles 100% of the metal scrap from our machining processes, which equates to 6.5 tons. Our cardboard and mixed paper products are also recycled 100%. Of the waste we place into our trash dumpsters – 80% is recycled and 20% is sent to the landfill. The paper products even get down to all of paper towels that are used and all the scratch paper that the office utilizes. In total, EXAIR recycled 35.4 tons of paper and cardboard in 2017. We focus on more ways to improve this percentage every year.

Another waste reducing factor that has proven to work out well for EXAIR is asking every customer if they accept digital invoices rather than requiring them to be printed and mailed. Thanks to our wonderful customers we have been able to eliminate 91% of all printed and mailed invoices which helps to reduce our resources used as well as the amount of materials that are possibly turned into solid wastes at their facilities. This also prevents the gas and vehicles necessary to deliver all of these invoices by mail.

To get back to what EXAIR products have done to help reduce waste, we were also able to optimize our own compressed air system by eliminating air leaks and have saved 1 million cubic feet of compressed air. We have also utilized our very own Chip Trapper Systems in our manufacturing areas and extended the water soluble coolant life from 6 weeks per changeover to 6 months per changeover. Keeping our coolant clean allows us to minimize the total amount of wastewater we recycle each year.

We continued to reduce our wastewater for reclamation – in 2017 we recycled 795 gallons, a reduction of 213 gallons compared to 2016, due to extending the life of our coolant.

On top of all the efforts above, we also continue to maintain RoHS compliance on all electronic products, as well as actively track our supply chains to ensure no Conflict Minerals are being sourced from the Democratic Republic of Congo.

If you have any questions on how we can help your facility reduce their use of compressed air or why we continue to reduce our wastes and increase our recycling efforts, contact us.

To see our full Sustainability Plan follow this link.

Enjoy Your Weekend,
EXAIR Corporation

 

Thank you to Kate Ter Haar for the Happy Earth Day image. Creative Commons License.
Thank you to AFS-USA Intercultural Programs for the volunteer image. Creative Commons License. 

Fluidics, Boundary Layers, And Engineered Compressed Air Products

Fluidics is an interesting discipline of physics.  Air, in particular, can be made to behave quite peculiarly by flowing it across a solid surface.  Consider the EXAIR Standard and Full Flow Air Knives:

Compressed air flows through the inlet (1) to the Full Flow (left) or Standard (right) Air Knife, into the internal plenum. It then discharges through a thin gap (2), adhering to the Coanda profile (3) which directs it down the face of the Air Knife. The precision engineered & finished surfaces serve to optimize the entrainment of air (4) from the surrounding environment.

If you’ve ever used a leaf blower, or rolled down the car window while traveling at highway speed, you’re familiar with the power of a high velocity air flow.  Now consider that the Coanda effect can cause such a drastic redirection of this kind of air flow, and that’s a prime example of just how interesting the science of fluidics can be.

EXAIR Air Amplifiers, Air Wipes, and Super Air Nozzles also employ the Coanda effect to entrain air, and the Super Air Knife employs similar precision engineered surfaces to optimize entrainment, resulting in a 40:1 amplification ratio:

EXAIR Intelligent Compressed Air Products such as (left to right) the Air Wipe, Super Air Knife, Super Air Nozzle, and Air Amplifier are engineered to entrain enormous amounts of air from the surrounding environment.

As fascinating as all that is, the entrainment of air that these products employ contributes to another principle of fluidics: the creation of a boundary layer.  In addition to the Coanda effect causing the fluid to follow the path of the surface it’s flowing past, the flow is also affected in direct proportion to its velocity, and inversely by its viscosity, in the formation of a boundary layer.

High velocity, low viscosity fluids (like air) are prone to develop a more laminar boundary layer, as depicted on the left.

This laminar, lower velocity boundary layer travels with the primary air stream as it discharges from the EXAIR products shown above.  In addition to amplifying the total developed flow, it also serves to attenuate the sound level of the higher velocity primary air stream.  This makes EXAIR Intelligent Compressed Air Products not only as efficient as possible in regard to their use of compressed air, but as quiet as possible as well.

If you’d like to find out more about how the science behind our products can improve your air consumption, give me a call.

Replacing Liquid Nozzles with Engineered Air Nozzles

I wrote a blog a few weeks ago about increasing efficiency with EXAIR Super Air Nozzles.  In the application for that blog we used engineered nozzles to place open pipes, resulting in an efficiency increased of ~65%.  This week’s installment of efficiency improvements boasts similar figures, but through the replacement of misused liquid nozzles rather than open pipe.

The image above shows a compressed air manifold with a number of nozzles.  BUT, the nozzles in this manifold are not compressed air nozzles, nor do they have any engineering for the maximization of compressed air consumption.  These are liquid nozzles, usually used for water rinsing.

In this application, the need was to blow off parts as they exit a shot blasting machine.  When the parts exit the shot blasting process they are covered in a light dust and the dust needs to be blown away.  So, the technicians on site constructed the manifold, finding the liquid nozzles on hand during the process.  They installed these nozzles, ramped up the system pressure to maintain adequate blow off, and considered it finished.

And, it was.  At least until one of our distributors was walking through the plant and noticed the setup.  They asked about compressed air consumption and confirmed the flow rate of 550 m³/hr. (~324 SCFM) at 5 BARG (~73 PSIG).

The end user was happy with the performance, but mentioned difficulty keeping the system pressure maintained when these nozzles were turned on.  So, our distributor helped them implement a solution of 1101SS Super Air Nozzles to replace these inappropriately installed liquid nozzles.

By implementing this solution, performance was maintained and system pressure was stabilized.  The system stabilization was achieved through a 61% reduction in compressed air consumption, which lessened the load on the compressed air system and allowed all components to operate at constant pressure.  Calculations for this solution are shown below.

Existing compressed air consumption:  550 m³/hr. (324 SCFM) @ 6 BARG (87 PSIG)

Compressed air consumption of (9) model 1101SS @ 5.5 BARG (80 PSIG):  214 m³/hr. (126 SCFM)

Total compressed air consumption of 1101SS Super Air Nozzles:

Air consumption of 1101SS nozzles compared to previous nozzles:

Engineered air nozzles saved this customer 61% of their compressed air, stabilized system pressure, improved performance of other devices tied to the compressed air system, and maintained the needed performance of the previous solution.  If you have a similar application or would like to know more about engineered compressed air solutions, contact an EXAIR Application Engineer.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE

Super Air Knife – Free Air Via a 40:1 Amplification Ratio

Intelligent Use of Compressed Air – Most industrial facilities have at least one air compressor.  The compressor is used to power anything from pneumatic tools, air powered equipment, compressed air cylinders, blowoffs and many more types of operations.  Improper use of compressed air can lead to unnecessary energy costs, high noise levels and dangerous exposure of personnel to high pressure air.

The EXAIR Super Air Knife uses only 1/3 of the compressed air of typical blowoffs.

LSAKpr_2mb
Long Super Air Knife with Plumbing Kit Installed and using the model 9060 Universal Air Knife Mounting Kit to Blowoff Laser Cutting Debris

By taking advantage of the Super Air Knife’s highly efficient design and the action of air entertainment, the Super Air Knife draws in large amounts of surrounding free outside air into the air stream. The result is a strong powerful air flow made up of a small amount of compressed air and a large amount of ambient air.

Capture

  • Compressed air flows through an inlet (1) into the plenum chamber of the Super Air Knife. The flow is directed to a precise slotted orifice. As the primary airflow exits the thin slotted nozzle (2), it follows a flat surface that directs the airflow in a perfectly straight line.  This creates a uniform sheet of air across the entire length of the Super Air Knife. Velocity loss is minimized and force is maximized as room air (3) is entrained into the primary air stream at a ratio of 40:1.  The result is a well defined sheet of laminar airflow with hard-hitting force and minimal wind shear is delivered.

By using a Super Air Knife – and the advantage of the high amplification via air entertainment – for part blowoff, cooling, or drying you can reduce energy costs, reduce noise levels, and eliminate harmful dead end pressures. Other air knives typically entrain surrounding air at a ratio of 30:1 or less.

EXAIR offers the Super Air Knife with materials of construction of aluminum, Types 303 and 316 Stainless Steel, and PVDF to cover a wide variety of application temperatures and environments. Other materials may be possible, pending review by our Product Design Engineers. The Super Air Knives are offered as the knife only, as part of a full kit, which also includes a shim set, auto drain filter separator, and pressure regulator.  The Super Air Knife can be fitted with Plumbing Kits and/or Electronic Flow Control making installation easier and help to save on air usage.

If you have questions about Super Air Knives, or would like to talk about any EXAIR Intelligent Compressed Air® Product, feel free to contact EXAIR and myself or one of our Application Engineers can help you determine the best solution.

Brian Bergmann
Application Engineer

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