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

What Makes A Compressed Air System “Complete”?

It’s a good question.  When do you know that your compressed air system is complete?  And, really, when do you know, with confidence, that it is ready for use?

A typical compressed air system. Image courtesy of Compressed Air Challenge.

Any compressed air system has the basic components shown above.  A compressed air source, a receiver, dryer, filter, and end points of use.   But, what do all these terms mean?

A compressor or compressed air source, is just as it sounds.  It is the device which supplies air (or another gas) at an increased pressure.  This increase in pressure is accomplished through a reduction in volume, and this conversion is achieved through compressing the air.  So, the compressor, well, compresses (the air).

A control receiver (wet receiver) is the storage vessel or tank placed immediately after the compressor.  This tank is referred to as a “wet” receiver because the air has not yet been dried, thus it is “wet”.  This tank helps to cool the compressed air by having a large surface area, and reduces pulsations in the compressed air flow which occur naturally.

The dryer, like the compressor, is just as the name implies.  This device dries the compressed air, removing liquid from the compressed air system.  Prior to this device the air is full of moisture which can damage downstream components and devices.  After drying, the air is almost ready for use.

To be truly ready for use, the compressed air must also be clean.  Dirt and particulates must be removed from the compressed air so that they do not cause damage to the system and the devices which connect to the system.  This task is accomplished through the filter, after which the system is almost ready for use.

To really be ready for use, the system must have a continuous system pressure and flow.  End-use devices are specified to perform with a required compressed air supply, and when this supply is compromised, performance is as well.  This is where the dry receiver comes into play.  The dry receiver is provides pneumatic capacitance for the system, alleviating pressure changes with varying demand loads.  The dry receiver helps to maintain constant pressure and flow.

In addition to this, the diagram above shows an optional device – a pressure/flow control valve.  A flow control valve will regulate the volume (flow) of compressed air in a system in response to changes in flow (or pressure).  These devices further stabilize the compressed air system, providing increased reliability in the supply of compressed air for end user devices.

Now, at long last, the system is ready for use.  But, what will it do?  What are the points of use?

Points of use in a compressed air system are referred to by their end use.  These are the components around which the entire system is built.  This can be a pneumatic drill, an impact wrench, a blow off nozzle, a pneumatic pump, or any other device which requires compressed air to operate.

If your end use devices are for coating, cleaning, cooling, conveying or static elimination, EXAIR Application Engineers can help with engineered solutions to maximize the efficiency and use of your compressed air.  After placing so much effort into creating a proper system, having engineered solutions is a must.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE

Increasing Efficiency With EXAIR Super Air Nozzles

Earlier this morning I received a phone call from a gentleman in search of a more efficient compressed air solution.  The application was to remove thermoformed plastics from a mold immediately after the mold separates.  In the current state, the application is consuming ~40% of the available compressed air in the facility through the use of (9) ¼” open pipes, consuming a confirmed 288 SCFM at 60 PSIG.  Due to the use of an open pipe, this customer was facing a safety and noise concern through the existing solution.

After discussing the application need and the desire to reduce compressed air use, reduce noise, and add safety, we found a suitable solution in the 1101 Super Air NozzleInstalling (9) of these EXAIR nozzles will reduce the compressed air consumption by over 65%!!!  Calculations for this savings are below.

Existing compressed air consumption:  288 SCFM @ 60 PSIG

Compressed air consumption of model 1101 @ 60 PSIG:  11 SCFM

Total compressed air consumption of  (9) 1101 nozzles:

Air savings:

This is the percentage of air which the new EXAIR solution will consume.  To put it another way, for every 100 SCFM the current solution consumes, the EXAIR solution will only require 34.38 SCFM. Installing these EXAIR nozzles will result in lower operational cost, lower noise levels, and increased safety for this customer – all while maintaining or improving the performance of the blow off solution in this application.

EXAIR Application Engineers are well versed in maximizing efficiency of compressed air systems and blow off needs.  If you have an application with a similar need, contact an EXAIR Application Engineer.  We’ll be happy to help.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE

Heat of Compression Dryers

A Heat of Compression regenerative desiccant dryer for compressed air

Before compressed air can be realistically utilized, it needs to be delivered to the point of use with proper volume and pressure, and it should also be clean and have some moisture removed.  We have information available regarding cleaning compressed air, but how do you dry the compressed air?  And why do you dry the compressed air?

Drying compressed air is akin to removing the humidity in the air when using an air conditioning system.  If the moisture is not removed, the effectiveness of the system is reduced and the ability to use the output of the system is reduced as well.

But, from a functional standpoint, what does this really mean?  What will take place in the compressed air system if the air is not dried and the moisture is allowed to remain?

The answer is in the simple fact that moisture is damaging.  Rust, increased wear of moving parts, discoloration, process failure due to clogging, frozen control lines in cold weather, false readings from instruments and controls – ALL of these can happen due to moisture in the compressed air.  It stands to reason, then, that if we want long-term operation of our compressed air products, having dry air is a must.

So, how can we remove the moisture in the compressed air?  One of the most common methods to remove moisture is a regenerative dryer, specifically, heat-of-compression type dryers.  A heat of compression type dryer is a regenerative desiccant dryer which uses the heat generated by the compression of the ambient air to regenerate the moisture removing capability of the desiccant used to dry the compressed air.

When using one of these dryers, the air is pulled directly from the outlet of the compressor with no cooling or treatment to the air and is fed through a desiccant bed in “Tank 1” where it regenerates the moisture removing capabilities of the desiccant inside the tank.  The compressed air is then fed through a regeneration cooler, a separator, and finally another desiccant bed, this time in “Tank 2”, where the moisture is removed.  The output of “Tank 2” is supplied to the facilities as clean, dry compressed air.  After enough time, “tank 1” and “tank 2” switch, allowing the hot output of the compressor to regenerate the desiccant in “tank 2” while utilizing the moisture removing capabilities of the desiccant in “tank 1”.

Heat of compression dryers offer a lower power cost when compared to other dryers, but they are only applicable for use with oil free compressor and to compressors with high discharge temperatures.  If output air temperatures from the compressor are too low, a temperature booster/heater is needed.

If you have questions about your compressed air system and how the end use devices are operating, contact an EXAIR Application Engineer.  We’ll be happy to discuss your system and ways to optimize your current setup.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE

 

Heated Desiccant Dryer by Compressor1.  Creative Commons License

Removing Static From Diaper Absorbent Material

This is where the absorbent material inside a disposable diaper is made

The image above shows one step in the process of disposable diaper manufacturing.  In this step of the process, the absorbent material is ground through a mill on the top of the “bunker” where it falls down a shaft and onto a mesh screen.  Once on the mesh screen, the material is repressed into the proper size and shape for placing into the diapers.

This manufacturer contacted one of our Russian distributors about the application because the milling of the absorbent material was creating static.  This static caused the material to adhere to the walls of the bunker chute and to unevenly distribute onto the mesh.  This unevenness leads to holes in the pressed/shaped absorbent material which translates to a reject rate of ~1 out of every 20 diapers.

An EXAIR Ion Bar

The ideal solution in this case needed to eliminate the static within the chute to allow for proper distribution on the mesh below and proper material placement into the diapers.  An Ion Bar was originally desired by the customer, but material accumulation on the emitter points was a concern so this solution was removed from consideration.

An EXAIR Ion Air Cannon

An Ion Air Cannon, however, was able to provide the desired solution by mounting outside of the chute and feeding a low volume of ionized air to remove the static.  The ionized airflow from the Ion Air Cannon is strong enough to permeate the full volume of the application, but low enough to not disturb the absorbent material within the process. Using an Ion Air Cannon allowed this manufacturer to eliminate defects and wasted materials, increase their throughput, and improve the quality of their products.  Defects dropped from 1/20 diapers to less than 1/1000.

If you have a similar application or similar needs, contact an EXAIR Application Engineer.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE

Keys to an Efficient Compressed Air System

How do I make our compressed air system efficient?

This is a critical question which plagues facilities maintenance, engineering, and operational personnel.  There are concerns over what is most important, how to approach efficiency implementation, and available products/services to assist in implementation.  In order to address these concerns (and others), we must first look at what a compressed air system is designed to do and the common disruptions which lead to inefficiency.

The primary object of a compressed air system is to transport the compressed air from its point of production (the compressors) to its point of use (applications) in sufficient quantity and quality, and at adequate pressure for proper operation of air-driven devices.[1]  In order for a compressed air system to do so, the compressed air must be able to reach its intended destination in proper volume and pressure.  And, in order to do this, pressure drops due to improper plumbing must be eliminated, and compressed air leakage must be eliminated/kept to a minimum.

But, before these can be properly addressed, we must create a pressure profile to determine baseline operating pressures and system needs.  After developing a pressure profile and creating a target system operating pressure, we can move on to the items mentioned above – plumbing and leaks.

Proper plumbing and leakage elimination

The transportation of the compressed air happens primarily via piping, fittings, valves, and hoses – each of which must be properly sized for the compressed air-driven device at the point of use.  If the compressed air piping/plumbing is undersized, increased system (main line) pressures will be needed, which in-turn create an unnecessary increase in energy costs.

In addition to the increased energy costs mentioned above, operating the system at a higher pressure will cause all end use devices to consume more air and leakage rates to increase.  This increase is referred to as artificial demand, and can consume as much as 30% of the compressed air in an inefficient compressed air system.[2]

But, artificial demand isn’t limited to increased consumption due to higher system pressures.  Leaks in the compressed air system place a tremendous strain on maintaining proper pressures and end-use performance.  The more leaks in the system, the higher the main line pressure must be to provide proper pressure and flow to end use devices.  So, if we can reduce leakage in the system, we can reduce the overall system pressure, significantly reducing energy cost.

 

How to implement solutions

Understanding the impact of an efficient compressed air system is only half of the equation.  The other half comes down to implementation of the solutions mentioned above.  In order to maintain the desired system pressure we must have proper plumbing in place, reduce leaks, and perhaps most importantly, take advantage of engineered solutions for point-of-use compressed air demand.

The EXAIR Ultrasonic Leak Detector being used to check for leaks

Once proper plumbing is confirmed and no artificial demands are occurring due to elevated system pressures, leaks in the system should be addressed.  Compressed air leaks are common at connection points and can be found using an ultrasonic noise sensing device such as our Ultrasonic Leak Detector (ULD).  The ULD will reduce the ultrasonic sound to an audible level, allowing you to tag leaks and repair them.  We have a video showing the function and use of the ULD here, and an excellent writeup about the financial impact of finding and fixing leaks here.

The EXAIR catalog – full of engineered solutions for point-of-use compressed air products.

With proper plumbing in place and leaks fixed, we can now turn our attention to the biggest use of compressed air within the system – the intended point of use.  This is the end point in the compressed air system where the air is designed to be used.  This can be for blow off purposes, cleaning, conveying, cooling, or even static elimination.

These points of use are what we at EXAIR have spent the last 34 years engineering and perfecting.  We’ve developed designs which maximize the use of compressed air, reduce consumption to absolute minimums, and add safety for effected personnel.  All of our products meet OSHA dead end pressure requirements and are manufactured to RoHS, CE, UL, and REACH compliance.

If you’re interested in maximizing the efficiency of your compressed air system, contact one of our Application Engineers.  We’ll help walk you through the pressure profile, leak detection, and point-of-use engineered solutions.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE

 

[1] Compressed Air Handbook, Compressed Air & Gas Institute, pg. 204

[2] Energy Tips – Compressed Air, U.S. Department of Energy

316 Stainless Steel Line Vac Conveys Cookies in Creamery

Cookies in need of pneumatic conveyance at creamery

An overseas ice cream manufacturer reached out to me recently with a request for assistance.  They were in search of a better means to transfer “inclusions” from a storage bin into the blending tanks of their creamery.  The “inclusions” in question, shown above, looked familiar.  I’ve found identical cookies stashed in my sons’ favorite places around the house, so I’m somewhat familiar with their transfer from one place to another.  Fortunately, in this application the cookie transfer is deliberate whereas it is always “magic” or “no one knows how it got there” when it happens at home.

Both solid cookies and crumbs (shown above) are conveyed.

Seeing as how this application involves the transfer of foodstuffs, we immediately explored a 316 grade stainless steel solution, and gathered the necessary data for determining the proper pneumatic conveyor (an EXAIR Line Vac).  Our Line Vacs utilize a high velocity airstream which travels along the ID of a conveyance tube to move material.  Because of this, application specifics like material/material size, bulk density, conveyance height and distance, and required conveyance rate play a key role in proper sizing.  Here’s how the specifics looked for this application:

 

Material:  Dry cookies and cookie crumbs, 8mm-50mm in diameter (5/16” – 2” in diameter)

Bulk density:  0.69 g/cm³ (43 lb./ft.³)

Conveyance height:  None

Conveyance distance:  5m (16.5 feet)

Required conveyance rate:  As high as possible, preferably in the range of 500kg/hr. (1100 lb./hr.)

Available compressed air supply:  170m³/hr. @ 5.5 BARG (100 SCFM @ 80 PSIG)

Material constraints:  316SS mandatory

 

With these details well defined, I used our empirical test data to appropriately size a suitable Line Vac.  In this case, we had a viable solution in our Heavy Duty Line Vac with regards to conveyance rate, but this solution is not the proper material.  So, we matched performance of a Heavy Duty Line Vac in our 316SS Line Vac using model HP6064-316.  Model HP6064-316 is not a stock option and not shown on the website, so having a proper dialogue with an Application Engineer was critical to dialing in on the right solution for this application.

Once the solution was confirmed, this customer was all set.  We worked with them on every aspect of the application solution and ended up shipping them (3) specialized Line Vacs in 316 stainless steel.  The Line Vacs are up and running, helping to make delicious ice cream for expecting customers.

If you have a similar application or are interested in exploring a Line Vac solution, now is the time to act.  We have a Line Vac promotion running through the end of October that includes a free 2” Flat Super Air Nozzle with the purchase of any Line Vac.  Application Engineers are available for any questions you may have via phone (1-800-903-9247), email (techelp@exair.com), and online chat.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE