Category: Ask Les

How can panel coolers prevent factory downtime?

Electrical and electronic control panels are the heart of factory production.  Any problems that occur with them can cause minor to major production hiccups, slow downs and potential need for a factory shut down.  Just as you would take care of your own heart, it only makes sense that you recognize the heart of production and take good care of it.

But often this does not happen.  How many times do you see control panel doors left open because they get “hot” inside. This creates a potential safety hazard and if the environment is not clean, it may cause dirt buildup inside the panels, on the controls – eventually leading to potential costly, premature failure.

As often as not, these control panels that are left open due to heat buildup is because of a lack of maintenance on whatever cooling system they may already have. It could be a simple external fans, external blowers, or traditional panel air conditioners. Even with water cooled systems, maintenance is necessary. External fans need filters, especially in dirty environments and these filters get dirty and require regular cleaning and/or replacement.  Similarly with blowers, perhaps even more often. Water cooled systems have small water lines and can scale up, preventing adequate cooling. Traditional air conditions are an even more critical machines for regular maintenance. Not only do filters need to be cleaned and/or changed regularly, especially in dirty environments, if air conditioners are on machines that have vibration the refrigerant inside may leak out the unit. It is important to recognize the cost of the smallest downtime due to a control panel “going down”.

So what can be done?  If whatever cooling system is working well and you do not have issues with control panels overheating, then of course nothing.  Keep doing what you are doing. But if you have even once have to open a cabinet door to vent out some heat – then you have a problem.  Would you ignore a sharp pain in your own heart? Well, that overheating is the panel’s pain.  

One solution is to overhaul the maintenance program on the control panels as that can certainly be a source of the problem but that in itself may reveal and create other costs. But it is one option.  Another option is to use a Nex Flow Panel Cooler.

Despite the use of compressed air for operation the Nex Flow Panel Cooler is essentially maintenance free.  Once installed, it can be left to operate under the worst conditions of a dirty factory environment, with high humidity, high ambient temperature and even on equipment that vibrates. How it works is simple – compressed air enters the Nex Flow Panel Cooler and the vortex tube component separates the compressed air into a hot and cold stream.  The hot end is exhausted as waste but the cold air goes inside the control panel to cool and keep the cabinet from overheating. The connection to the cabinet has a built in exhaust to vent out the hot air displaced by the cold air. Since there are no moving parts, and no refrigerant chemical inside the unit, the Panel Cooler can handle equipment vibration.  The air entering the cabinet keeps the cabinet at a slightly positive pressure keeping out any humidity and any dirt and particulate in the environment. The effectiveness of the air conditioning depends solely on the temperature of the compressed air and not the environment making Panel Coolers ideal to use in hot and humid locations. There is no condensate produced that needs to be disposed of and you do not have to worry about replacing filters. The only basic requirement is to properly filter the supplied compressed air.  To conserve energy, a thermostat and solenoid valve control system can turn the air on and off as required.  Alternatively an electronic thermostat system can be used.  To keep the cabinet constantly at positive pressure to keep out a very nasty environment, a bypass system can be installed around the solenoid to always have a very small amount of compressed air flowing even when the unit is off.

If maintenance is not adequate or perhaps the environment is just so unfriendly it causes serious and costly issues for whatever the reason for problems with traditional air conditioning or other cooling systems, the Nex Flow Panel Cooler can be a viable option and the extra energy costs often offset by the shorter life span, or damage to controls and other problems created using other systems.

TRY NEX FLOW PRODUCTS BEFORE PURCHASING

Nex Flow offers in the USA and Canada (as do many of our representatives worldwide), a risk free product trial  to potential customers and it is done in such a way to benefit all sides. Usually the trial period is limited to a maximum 30 days but in some cases, especially for larger projects, that time can be extended. Pneumatics is not a technology that is easily understood by everyone.  Even in engineering schools, a great deal of teaching time is focused on hydraulics but very little in pneumatics.

If and when someone enters the pneumatic field – the focus is often in a very narrow area.   Air compressor companies may give lip service to an entire system but their focus is primarily on the compressor room.  A piping supplier would be focused on the piping and filtration companies would obviously be focused on the filters. Tooling, blow off, cooling and other end use application, the focus is too much on the use of the equipment without considering the entire system. That being said – it takes a great deal of experience, and deliberate interest in the entire system to truly give the best outcome to a customer.  For this reason, Nex Flow insists upon understanding the entire system and the issue faced by clients before making recommendation on what to try.

A good volume of customers are in the same position as someone freshly entering the pneumatics field, and except for some basics understanding from classes and workshops, a more in-depth explanation will often help with decision making. A partial understanding of the concept can sometimes lead to inappropriate installation and test. For example, if an air knife is installed and does not work, did the issue steam from the application or installation?


A real example occurred years ago at one facility where a 24” air knife was installed for a blow off application. The issue was that the unit was not powerful enough. What happened was that the person in charge had hooked up a very small diameter airline that was also quite long.  This caused excessive pressure drop in the airline so the actual pressure at the point of use was much lower and hence less powerful. At first – the installer refused that the airline might be too small – but once he accepted to change the airline diameter to a much larger one – everything was resolved.

Some companies supplying similar technology as Nex Flow® have their “application engineers” that is not always very knowledgeable about the whole system offer a 30 day unconditional trial period.  With this many returns happen because no one is really there to assist when there are issues. One of our current customer had such an experience with a competitor – so much that he was skeptical about whether the system can even work for the application. The competitor sent one unit for test – it didn’t work, so the unit was sent back. With Nex Flow – we help customers explore and learn about the actual system and pinpoint why it did not work. The issue was simple – the unit was simply hooked up without the appropriate parameters. Now – this customer is using our air knives and are quite happy.

So this is why Nex Flow personnel always probe deeper to not only understand the customer’s application but the customer’s environment, and system. Is there adequate compressed air?  What about cleanliness in the airline? We even ask if the compressor is far or near the application (and yes, that can make a difference in some cases). If an application is tried and does not work – we endeavor to understand why because we want to learn and improve too!  Nothing is sent for trial unless we are quite sure it will work. Of course sometimes we get the opportunity to explore a new applications where we sometimes cannot guarantee if the system will work but we will still try the test if the customer is willing.

The point of all this is simple – we recognize the value of both the customer’s time and ours.  It is to the benefit of both parties to understand the customer’s operation, and for the customer to understand both the potential and limits of Nex Flow® technology and the parameters of operation.

In some cases it may take time for us to review provided information and may need to inquire additional information. For customers who have already had experience using the technology. What’s very nice is that the client’s have tried and loved the product due to the high quality of manufacturer and the “extra” we provide in each product. For example, most air knife providers do not anodize their aluminum versions – we do.  Our cabinet enclosure coolers are all stainless and even less costly than aluminum versions provided by old competitors. We enjoy product comparisons and as our team of researchers and engineers constantly strive to improve our products.

If you are not familiar with Nex Flow technology, or maybe you have used competitive products, successfully or non-successfully but not familiar with the Nex Flow® brand-  we certainly encourage to try before you buy!

Adding Attachments to Air Flow Amplifiers

A compressed air flow amplifier is also called an air mover because it can move a significant amount of air. However, when you add an attachment at either the suction inlet or exhaust (amplified airflow) outlet, you will incur a back pressure, reducing the amount of amplified or moved airflow.

This back pressure can be minimized by maintaining a large diameter in the tube or pipe attachment, minimizing any bends and restrictions, and keeping the overall length of the attachment as short as possible.

Nex Flow Air Products Corp. manufactures compressed air-operated products for blow-off, drying, moving, and cooling and offers products to optimize compressed air use. If you have any questions concerning the use of compressed air –

Ask Les.

Adding Attachments to Air Flow Amplifiers

Video url : https://youtu.be/uq7s4tL8l0g

Compressed air is a tricky technology to deal with because it is a compressible fluid and is subject to all sorts of things. Yet 70% of all compressed air is still sued for blow-off and cooling because it is versatile. But it can be used more efficiently.

One of those applications that can be much more effective is when using engineered compressed air nozzles. Properly designed engineered nozzles work by entraining surrounding atmospheric air and compressed air to convey energy normally lost as pressure drops and noise. But not all air nozzles are engineered. And some engineered nozzles are not very well designed. This may not matter in small applications, but when you add up the nozles in a large facility, it can be a significant amount of money.

The first thing to decide is if you want to cool a part or clean it. In the first case, flow is more important than force. In the second case, force is more important than flow. Then there is comparing air nozzles. Assuming that manufacturers are honest about their specifications (which is not necessarily the case), you need to look at both force and flow.

This is far more critical when force is required. In this case, the force/unit air consumption is the best thing to look at. The most efficient (and effective) nozzle will have the highest force/unit airflow (Force/SCFM ratio). It does not matter how force can vary among a variety of nozzles because in a proper installation, you use a regulator to cut back the pressure to set the force you need; Force above what you need only uses more energy. But in real life, here is where it gets tricky…

How Piping Can Effect Air Nozzle Performance

Let’s assume you have an installation with a set of nozzles from one supplier. You find a second brand that gives the same force at the same pressure. And the cost for the nozzle is a bit less. You have no regulator on your system. So you replace a few nozzles. But…. then you find that the actual force is less than specified? Yes, according to what you read, it should be the same! What went wrong?

If you check the specifications further, you will find that the replacement nozzles use only 1 SCFM more than the one you are using. It certainly does not seem much, but…. that extra flow going through the piping, which is typically the same size as the nozzle, can cause enough extra pressure drop that the effective pressure at the nozzle entrance is just a little less, which also makes less force. That is how sensitive the nozzle effectiveness can be. So if you are replacing any nozzles, check the force created at a particular pressure and the air consumption at that pressure. The odds are that the pressure at the entrance to the nozzle is NOT the same as you think it is due to pressure drop.

When considering the use of compressed air nozzles, consider the force it produces, usually specified at a particular pressure, and the air consumption.

Nex Flow manufactures products for compressed air blow-off, cleaning, drying, moving, and cooling and also offers related products for filtration and optimization in addition to consultation in their field.

Video url : https://youtu.be/RhjnHSy4_co

Compressed air-operated air knives can be utilized as a barrier in some applications to prevent contaminants from one area from getting into another area. This is possible because of the laminar flow produced by the air knives. The small amount of compressed air in the air knife gap entrains the surrounding air on each side of that exit point. But that arrow sheet of air keeps the two sides separate.

One example is mounting an air knife over the door of the closed machine doing welding. Welding fumes are produced within the machine. The compressed air can be automatically started when the door is opened to remove the finished part. The air can flow down over the door opening, creating a barrier to prevent most fumes from exiting the machine. Yet the part can still be removed. Once the door is closed, the compressed air goes off. Minimal energy is used because it only operates when the door is open.

Nex Flow manufactures compressed air products for drying, cleaning, cooling, and moving and offers consultation and other specialty-related products to improve and optimize your compressed air systems.

Video url : https://youtu.be/Qvo80XOgqec

The biggest criticism against vortex tube-operated air conditioners for control panels is their use of compressed air. Still, in certain situations, it just makes sense to use them depending on the importance of reliability and the nature of the factory environment.

Nex Flow Air Products Corp. manufactures compressed air-operated products for blow-off, moving, and cooling applications to optimize the use of energy with safety and the environment in mind.

Video url : https://youtu.be/dBjuJaIjw9w

Compressed air flow can be restricted because of improper pipe sizing, unnecessary restrictions in the line, air leaks and lack if cleanliness in the system.

Nex Flow Air Products Corp. specializes in the use of compressed air technology for cleaning, drying, blow off, cooling and moving with the goal of saving energy, and optimizing compressed air use efficiently and effectively. Also offer other specialized technologies related to compressed air use.

Video url : https://youtu.be/N6IcWCCNz2A

When utilizing a static bar with a compressed air operated air knife, the further you are away increases the time needed for static charge removal so you may need a stronger static bar if dwell time is inadequate (high speeds) or the static charge is very high.

Nex Flow Air Products Corp. specializes in the use of compressed air technology for cleaning, drying, blow off, cooling and moving with the goal of svaing energy, and optimizing compressed air use efficiently and effectively. Also offer other specialized technologies related to compressed air use.

Questions may be submitted on the any application you may have or planning in the use of compressed air.

Video url : https://youtu.be/BIEc-BjTdng

Cleaning Air Amplifiers

Compressed air amplification products have small air exit “gaps” and if not properly filtered can get dirty and block airflow. But there is an easy way to clean.

No matter how well your compressed air supply is filtered, at some point in time, there will be particulate buildup in the blow-off product used and the most common blow-off products ignored for this are air knives and air amplifiers.

These products operate using an air gap where the compressed air exits over aerodynamically designed surfaces to entrain surrounding air and convert pressure lost as pressure drop and noise into useful airflow.  Over time deposits can build up over these surfaces which can negatively affect the entrainment and reduce the output airflow efficiency.  Carefully wiping these surfaces can be easily achieved but wiping with care to avoid damage to these surfaces.

However, the problem of particulate buildup can be inside the plenum chambers of the air amplifier or air knife.  In this case, it is more complicated.   This problem manifests in uneven flow from the air amplifier or knife.   This is detrimental to the production process because the cleaning or drying (and even cooling) application for the particular product can be less effective with this uneven flow.

If left too long, the device may need to be removed from production, disassembled, and cleaned if too clogged with dirt and debris.  However, when the problem manifests itself with the uneven flow, an easy method to clean is described in the video where you simply keep the air flowing, but at a lower pressure for safety, loosen the body and cap, and blow out the particulate, then retighten,

Nex Flow Air Products Corp. has representatives worldwide to assist you in compressed air blow off, cooling, drying, cleaning and conveying.

Video url : https://youtu.be/gIGBhnQJMGk

Why is the Compressed Air Pressure Too Low

As discussed in this video, there are causes and solutions to situations where the compressed air pressure is too low for some factory applications.

All equipment that uses compressed air is designed to operate at a certain minimum air pressure entering that equipment.   If the pressure at the point of entry is too low, the equipment can slow down, not work as well, or cease to operate entirely.

One of the common things done, but which should be avoided, is to increase the pressure output of the air compressor.  This generally yields more pressure at the point of entry to the compressed air-consuming device.  But it increases energy consumption needlessly.

It is better to address the causes of where the pressure is being lost in the transmission of the compressed air to the air-operated device.   This can be many things as explained in the blog.

Nex Flow Air Products Corp. manufactures specialized compressed air products for blow-off, cooling, drying, and moving and provides accessories such as special filtration technology for improving compressed air systems and optimizing compressed air use.

Video url : https://youtu.be/rdeoQjsmpWo

Compressed air amplification is a term that is sometimes abused and not properly explained, It is explained in this video.

Nex Flow Air Products Corp. manufactures compressed air nozzles, jets, air knives and air wipes utilizing air amplification technology.

Vortex Tubes are used for spot cooling. They utilize compressed air. When using vortex tubes you need to be aware of the effect of the dew point of the compressed air.

Nex Flow Air Products manufacturers air blow off, air moving and spot cooling products and other specialized technology that operate with compressed air.

Video url : https://youtu.be/SQpu1clfrvw

Compressed Air Blow-Off Force is Too Low

If your blow-off nozzle, air knife, jet, or amplifier force is too low, it could be from several factors that need to be checked.

Compressed air is an energy source that is only sometimes understood.   When used for blow-off and the expected force is low, or drops low after some time, it can be consuming as to the cause.

Presuming near zero leaks and adequate compressed air capacity, the primary thing to check when the force seems too low is for pressure drop.  You need to check what could be in the compressed air system causing excessive airflow resistance such that the pressure at the point of use is lower than necessary.

By installing a gauge near the point of use and taking a pressure reading while the compressed air-consuming device is operating, this can be confirmed.

One of the things NOT to do is to increase the pressure that the air compressor produces.  This not only ends up consuming more energy, it will not solve the problem as explained in the video.

Increasing the size of the engineered air nozzle or the gap in an air amplifier by adding shims to open the gap in an air knife will also generally fail.   This is because as you try to draw more air through the compressed air delivery system to the blow-off location, the pressure drop can be aggravated and the force can fall even further.

The source of access pressure drop can be improperly sized fittings, filters, and the air system itself.  Replacing fittings and filters can be addressed but if its system design, then the solution can get much more complicated.

Nex Flow Air Products Corp. manufactures compressed air blow-off products and can assist you with blow off applications and issues.

Video url : https://youtu.be/jTnBQa7rzVg

Compressed air amplification draws in atmospheric air and mixes it with compressed air to amplify air flow. Vortex Tubes create freezing air from compressed air. But can you combine the cold air with the amplified air efficiently and effectively?

Compressed air amplification draws in atmospheric air and mixes it with compressed air to amplify airflow. Vortex Tubes create freezing air from compressed air. But can you combine the cold air with the amplified air efficiently and effectively? This video explains. Nex Flow Air Products Corp. are specialists in compressed air for blow-off, drying, moving, and cooling.

Vortex tube technology and air amplification technology are entirely different things.   A vortex tube takes compressed air and within the device, compressed air separates and spins.  It exits one end cold and the other end hot.  While the hot air has no use generally, the cold air has many uses for spot cooling in open spaces or in cooling enclosures.   An air (flow) amplifier entrains surrounding air with a small amount of compressed air, converting energy normally lost as pressure drop and noise into a powerful “amplified” stream of air.

The question sometimes arises of combining the vortex tube’s cold air with the air amplifier.

If the cold air from the vortex tube is piped into the compressed air inlet of the air amplifier, the amplifier will not work because the pressure from the vortex tube is close to atmospheric.  In fact, the back pressure from the air amplifier will push all the cold air back through the vortex tube and stop working, pushing the compressed air out of the hot side of the vortex tube.

If the cold air from the vortex tube is directed into the center of the air amplifier which entrains the surrounding air, the cold air “may” have some effect but will be minimal.  This is because the entrained air will be 5 to 10 or more times that of the air from the vortex tube.   Assuming adiabatic mixing, the air from the air amplifier will not be cooled significantly.

Video url : https://youtu.be/rERF4hFwmwg

Drying complex parts may require a combination of nozzles, jets, and air knives.

A complex cart can have an odd shape, plus holes and crevices where water can collect.  In such cases, it may require several steps in the drying process.   Complex parts often have personnel drying manually with a compressed air blowgun.  As labor shortages occur, the necessity to automate the drying increases.

The more complex the part, the more steps may be required to clean and dry.   Often if the parts were manually dried, they are on a conveyor and an attempt is made to dry the part in the same process.  Sometimes this is possible, but sometimes the part may be so complex it needs to be robotically handled, perhaps turned in different directions to dry adequately.

This would be the case if the part were picked up and otherwise handled and dried when it was dried manually.

But if it was manually dried before on a conveyor and not handled, it’s usually possible to keep the same process.   Small holes and crevices can be blown dry with small nozzles and if they are larger, you can utilize air jets or larger nozzles and even annular air flow amplifiers to splash out the water.

It is essential to ensure that the water does not splash from one hole or crevice into another so the order in which these areas are dried is essential.   This can be complicated and may entail an additional drying step or more.

Once the holes and crevice and any other difficult spot holding water are dried, residual water on the part surface is left from splashing, it is sometimes appropriate to sweep the part with a halo of air knives to do a final wipe.

Compressed air drying is efficient because any remaining water droplets will be tiny and evaporate quickly.

Video url : https://youtu.be/gaBFVXZWFuY

This video provides a cost-effective solution to collect and convey dust a long distance without electricity. Portable and simple.

Annual air (flow) amplification products such as Nex Flow Air Amplifiers operate by utilizing the Coanda effect to draw in a large amount of volume at their inlet end by utilizing a small amount of compressed air.   When a hose or pipe is attached to the downstream exit of this amplified airflow, whatever fumes, dust, or light particulate is drawn into the inlet can be conveyed through this pipe and tube.

However, back pressure is created to reduce the amplified effect when an attachment is added to an Air Amplifier.   In most situations, the actual volume of dust, fumes, or particulate can be conveyed about 10 feet (3 meters) from the inlet to the Air Amplifier is about ten (10) times the compressed air consumption because of this back pressure.

If you want to go longer than this distance, the back pressure increases, and the volume will drop significantly.  One way to boost the distance that material can be conveyed is to add an in-line compressed air operated conveyor such as the Nex Flow Ring Vac.

This device is designed specifically for conveying of materials long distances and can extend the distance conveyed up to five times or more depending on the material being conveyed.   The Ring vac unit utilizes a venture effect to create a high vacuum at the product entrance allowing it to convey greater distances.

Ring vacs are also used alone for handling heavier solid materials such as plastic resin for hopper loading but when used in conjunction with Air Amplifiers, they overcome the back pressure issues and allow for the transfer of fumes, dust, and particulate which they entrain to much greater distances.

For advice or suggestions on similar applications or any applications of compressed air used for blow-off, cooling, or moving, don’t hesitate to contact me.

Video url : https://youtu.be/CuUenIeTm2M

When a compressed air flow amplifier gets dirty, there is no need to remove the units from the line.

Nex Flow compressed air-operated Air Amplifiers are annular flow amplifiers often called “air movers.”  They utilize the Coanda effect which operates by taking the energy normally lost as pressure drop and noise and then converting that energy into functional high kinetic energy flow.

This output energy is used for cleaning, drying, and even effectively and efficiently cooling manufactured parts. These assemblies are rugged, with long life, and essentially no maintenance as long as the compressed air supply is kept clean and dry with good drying and filtration.

The reality, however, is that a compressed air system, for whatever reason, is sometimes lacking this clean and dry air at the point where the Air Amplifiers are installed.   The issue of dry and clean compressed air may or may not be endemic to the entire compressed air system and may only be an issue where the units are installed.

This is why Nex Flow always recommends point-of-use filtration and even point-of-use compressed air driers (all of which are offered as an option) to ensure that the compressed air supply entering the devices is adequately clean and dry,

Regardless of why there may be a cleanliness problem, should cleanliness issues occur, it is always recommended that it be investigated and corrected after any cleaning to avoid the necessity of cleaning in the future.

Even with a clean system, there may still be some dirt buildup in the Air Amplifiers, although hopefully an infrequent occurrence.   For a minor buildup, this video shows an easy way to remove this particulate but simply loosening the bolts that hold the body and cap together of the Air Amplifier while the compressed air is still flowing and letting the air blow out any deposit.  Then just re-tighten.

For any questions on the use of compressed air for blowing, drying, cleaning, moving, or cooling “as Les”

Recognizing the effect of pressure drop in your compressed air system is essential to ensure your equipment is working optimally.

Except for possibly compressed air leaks, the greatest waste of using compressed air is not addressing unnecessary pressure drops.

Pressure drop is when pressure loss occurs inside a compressed air system. This can happen at numerous points between the central compressed air tank and end-point of use applications if anything stands in the way to inhibit the flow of pressurized air.

There will always be losses in compressed air transmission as it is a natural occurrence.    But the goal is to minimize it.  The size of the compressed air delivery piping is often the culprit for high loss.  When the piping is installed initially, it may have been sized for a particular compressed air load.

Over time, the air consumption requirements may have increased or otherwise substantially changed such that one factory area may be optimized or even oversized (which is fine) while another faces heavy pressure losses.

It is wise to audit the equipment’s compressed air consumption and relate the volume to the diameter and length of piping that supplies that piece of equipment.  In these instances, it could be economical to change the piping size or add a parallel air supply line to correct the issue.

Another source of pressure loss is undersized, blocked, or worn-out fittings and under-maintained filters.   These fittings and filters need to be in top working order to keep pressure loss low and keep the compressed air system clean and dry.

Leaks, of course, also cause pressure loss, and these leaks not only occur in piping but are also common in worn-out fittings and filters with auto drains that are stuck open and not corrected. Even manual valves are sometimes accidentally left open or only partially closed.   These waste energy in lost air and reduce system pressure, negatively affecting equipment operation.

Please message me if you require assistance using compressed air for blow-off, moving, cooling or drying or on any questions about your compressed air system.

A Better Way to Cleanup with Compressed Air

Its better to vacuum using compressed air for cleanup for safety reasons. Units are available with attachments for this purpose.

There are two angles to consider when utilizing a compressed air-operated air knife – the impingement and sweep angles.

The impingement angle is the angle of the air knife when aimed at a target that is being dried or cleaned.  This depends on various factors.  If the target is flat and slow-moving, and the air knife is very close (under 6 inches or 150 mm), the angle can typically be between 3 to 5 degrees against the flow direction. If the target is flat and moving faster, the angle may need to be increased.

It can also depend on the nature of the material being removed and the surface tension of the material surface holding the material that needs to be removed.   If the air knife is further away, the impingement angle may need to be increased.  As you move away, the airflow from the air knife will start to fan out more, reducing the point force and spreading the impingement force over a wider area.

An air knife is typically placed 4 inches to 12 inches from the target.  If the material is heavy oil versus light water, for example, you should be closer to address the more difficult to remove oil.   If the air knife is used for cooling, it is usually placed further away for a more extensive area cooling effect.

The sweep angle is how to orient the air knife to address the entire part.   For example, in the video, we use a cylindrical product, such as a bottle that needs to be dried.

In this case, the air knife is oriented at an angle so that as the bottle moves passed the air knife, the air knife blows onto the cylindrical surface with the air touching the top of the bottle first.  As the bottle continues past the air knife, the air contact point moves down the bottle.  This removes the liquid from the bottle but pushes the liquid down and off the bottle.

This sweep angle can be anywhere from 30 to 45 degrees, depending on the speed the product moves past the air knife.    In these bottle drying applications, one air knife is used commonly per side as the bottle may also rotate along the conveying system.

There are certain factors to consider when using an adjustable or non-adjustable vortex tube cooling system.

When purchasing a vortex tube device, you must examine the material, construction, adjustability, and noise abatement.

The vortex tube is a unique device that separates compressed air into a hot and cold stream.   The concept was discovered in the 1800s but commercialized in the 20^th century in the late 1960s. It still took well into the 1980s and 1990s to become more widely known, understood, and applied.

Even today, the concept of the vortex tube has yet to be discovered in many places worldwide.  The main advantages of the vortex tube are its ability to “spot cool” with a very small footprint, using only compressed air.

It has found significant use in cooling electrical and electronic control panels, especially in factory environments that are very dirty and humid and where maintenance costs can be high since vortex tubes operate essentially maintenance-free.

Another growing market is tool cooling in dry machining applications as new materials are developed to replace the need for coolants and their detrimental environmental effects.    Nex Flow, in particular, works to improve the efficiency and function of its vortex tube products.

The material of the vortex tube can be anything from aluminum to brass to stainless steel.  However, stainless steel has now become the primary material used for the body of the vortex tube by most suppliers of importance.

This is because of the environment where vortex tubes are commonly used.  As they are used to cool, it only stands to reason that they are used in hot areas or a hot factory environment.   Many of these environments can negatively affect materials such as aluminum and shorten the product’s life span.

The quality of construction is essential.   Brazed or welded parts must be done correctly, so they do not break off.    Any welds should be clean with no weak spots.  Any vortex tube and especially vortex tube packages (including unique sleeves, special attachments, etc.) should be appropriately assembled.

The material of O-rings used and the quality of the material can be very important for some applications.  For example, vortex tubes are often packaged as electrical and electronic cabinet enclosure coolers such as Nex Flow Panel Coolers.

Material quality is essential and mandatory for electrical certification in most countries.   Nex Flow has these certifications.  Quality of construction and assembly is also necessary for optimum performance to optimize its energy use in producing the cold air required.

Adjustability in a vortex tube is achieved by controlling the airflow out of the cold and hot ends.  A relationship exists between the temperature drop at the cold end and the flows out the cold end.  The smaller the flow out of the cold end, the greater the temperature drop, and vice versa.  In some applications, you want to avoid adjustability, but Nex Flow can advise and provide the appropriate setting for the application.

Vortex tubes can be pretty noisy, and adequate muffling at both the hot and cold ends (especially at the cold end) is important.   How the mufflers are designed, and the materials used can affect that muffling level. Most companies use plastic as a muffling material. Nex Flow uses a biodegradable natural material that is also fire retardant keeping safety and the environment in mind.

When tested against plastic, usually a foam material, it even proves to be better at a sound reduction.

Nex Flow Air Products has participated in several industrial trade exhibitions, directly or through our various representatives worldwide.

Typically a great deal of traffic comes by when we demonstrate our products.  For various reasons, Nex Flow compressed air-operated air knives have been popular at such exhibitions.

Air Knives are essentially long flat air nozzles.  They often replace pipe lengths with holes or rows of individual air nozzles.   Nex Flow manufactures two versions of air knives: the Standard Air Blade air knife and the X-Stream Air Blade air knife.

The standard version is an older design where the compressed air exists in the slot along the length of the air knife and bends 90 degrees around a unique aerodynamic designed surface, entraining surrounding air from the atmosphere.

Combined with entrained atmospheric air, this compressed air converts energy previously lost as pressure drop and noise into high-velocity and powerful airflow.  This design is still used extensively for specific applications where the 90-degree bend is helpful.

One example is when an air barrier, such as protecting a camera lens in a dirty environment, can be utilized.  The air knife may be placed in such a way that the surface of the air knife where the compressed air and entrained air occurs is made flush with the camera lens, creating a laminar airflow barrier.

The more modern air knife designs have compressed air exiting the air knife slot straight, without a bend in the flow.  Again, the surfaces before the air exit must be aerodynamically designed to entrain an optimal amount of atmospheric air with the exiting compressed air.

In the Nex Flow X-Stream Air Blade air knife design, the combination of compressed and entrained air is highly efficient and produces a sharp and targeted flow pattern with a high force-to-compressed air consumption ratio.

Compared to the older standard air knife designs, they are 15% more efficient in this force-per-air consumption ratio.  As a result, most applications tend to prefer these modern designs. While both air knife designs reduce noise levels, the contemporary design is significantly even better, adding to its popularity.

A considerable advantage of air knives, besides reduced noise and increased energy efficiency, is that the airflow produced is laminar flow over a significant distance. One problem with a pipe with holes is that the air exiting the holes becomes turbulent quickly.  This diminishes the effective force available for blow-off or cooling very quickly, so it is only helpful if the pipe is close to the surface being addressed.

This also creates higher noise levels and uses much more energy.    Rows of engineered nozzles can be effective but less efficient overall than an air knife.  Because air nozzles have a specific flow pattern, the height of any manifold must be carefully set to optimize performance.

The pattern of each nozzle must touch to address the entire target but not overlap, as that would create turbulence and negatively affect the result.   With an air knife, the flow along its length is continuous and is much more flexible for installation.

This video from an exhibition in Turkey demonstrates the Nex Flow X-Stream Air Blade air knife to show its performance and low noise level.

Nex Flow compressed air-operated air knives are produced in two versions.   The standard version operates by having compressed air exit the knife for a specially designed surface and mix with atmospheric air to produce a laminar flow of high-velocity air.

The compressed bends 90 degrees as it passes over this aerodynamically shaped surface.    The more modern X-Stream Air Blade air knife also works with the compressed air exiting the knife and mixes with atmospheric air to produce a laminar flow of high-velocity air.

However, the air goes straight and does not bend.  Each version has its particular specifications and advantages depending on the application. Both air knives have a laminar flow, but the flow profiles differ.   That needs to be considered in any application as both flow profiles spread the further the air knife is from the target.

Energy efficiency may also be a consideration, primarily if multiple air knives are utilized at the factory location.   The more recent versions have a higher force-per-air consumption ratio and are 15% more efficient than the older standard designs.

Both types can generally be used for the same applications as a barrier.  However, when the air barrier must maintain contact with the protected surface, the standard air knife is ideal if the distance covered is relatively short.  An example would be creating an air barrier over a camera or sensor lens.

The standard air knife can be placed to take advantage of the 90-degree bend over the surface where the compressed air exits the air knife.   The final surface before the air leaves the device can be placed flush with the lens.

The laminar airflow clings to the lens and maintains contact along the entire surface, providing an effective barrier to floating debris, particulate, and moisture.  Standard air knife designs have been used to protect outdoor camera lenses against ice forming in cold weather.   The laminar flow can be extended a fair distance by continuing the clinging action beyond the air knife itself with a continuous surface.

This was even done at a university project where the standard air knife made an airflow cover for a game that floated pieces on top of this air barrier.

The X-Stream Air Blade air knife will produce a sharper or narrow profile and concentrates force over a greater distance than the standard design. This makes it more economical when more considerable distances require a barrier of air.

One example is using the X-Stream Air Blade air knife on plastic injection molding machines or machining operations where mist must be contained when the machine door is opened for inspection or material is added or removed.

The air supply can be turned on automatically when the door opens and off when it closes. There are many operations where visual access is required, but particulate, dirt, debris, and even heat must be contained.   These air knives can provide visual access with the necessary barrier. Because of the laminar flow from the air knife, it can provide an effective heat shield to some extent.

These air knives can be helpful when a critical part is washed and needs to be kept clean.   Instead of using plastic at the entrance and exit of a washer to contain water mist, use air knives.   Plastic will get dirty and negatively impact the cleanliness of a washed part after it is washed.  An air barrier eliminates that problem.

Industrial cameras, as well as all sorts of sensors, are increasingly used in industrial applications.  Many of these are in very hot and humid areas that can also often be difficult to reach, making maintenance difficult.   This requires a maintenance-free device to cool, and few options are available.

You cannot use fans because they can be easily clogged and damaged.  In addition, you are trying to cool with factory air that can be dirty, corrosive, and otherwise damaging.  The temperature in the camera’s area will also be very hot, and fans will simply not work.

Other options are necessary to prevent heat damage to the camera that requires preferably zero or near zero maintenance.

This leaves three options: using pure compressed air to cool, water, or vortex tube technology.

Using pure compressed air to cool can be costly, especially if multiple cameras require cooling.   The compressed air will cool, but it may also be warm because it heats up in a hot area. Increasing the volume required to keep the camera cool may be necessary due to the warmer compressed air supply.

The air would usually be supplied into a camera housing used to protect the camera with holes or some vents to release the compressed air put into the housing.

Using water to cool is a standard option, but it has severe drawbacks.  Because the water will be pretty warm, if not hot, after cooling, and the system will be subject to scale deposits forming inside the cooling lines.   The water supply lines to the camera are small in diameter, so even a small amount of scale can be an issue where it will not cool very well.  Scale can build up on the water supply line and in the camera housing.  This requires the removal of the camera to descale properly.

While water may be treated to prevent scale, treatment only slows scale formation.  Eventually, cleaning will be required.  This results in downtime and added maintenance costs.  This is an essential factor as maintenance costs rise over time.    However, if the water treatment is perfect and the water itself is very soft, it can still be an option in some cases.    But this ideal situation is rare.

Using a vortex tube is a popular method to cool cameras.  Even if the compressed air supply is warm, the vortex tube creates a cold stream of air at one end, which would be piped into the camera housing.   The vortex tube can be adjusted to compensate for any high compressed air input temperature so that the air supply into the housing provides good cooling.

A vortex tube alone can be used if there is a vent or holes in the housing to vent the cold air after it cools.  But if there is no vent, a Panel Cooler can be used, which is self-venting to cool the camera.  This is much more energy efficient than just using compressed air alone because you use much less compressed air with a cold air supply.

With the vortex tube, or even with compressed air alone, it is essential that the air supply be clean and dry with an adequate, near-point-of-use filtration system to remove loose moisture and oil if necessary.   For camera cooling applications and other critical cooling, a point-of-use low-cost drier should be considered as well.

Nex Flow Ring Blade air wipes are popular for drying extruded parts.    Air Wipes in general, have been available for years and are typically designed per application.   Usually, using compressed air (which makes them compact), the energy used has only sometimes been a significant consideration but has become necessary as energy costs increase.

High costs of original designs and energy importance have led to the development of more efficient products like the Nex Flow Ring Blade air wipe.   This product is produced in volume, and the cost per unit has dropped since this design can address numerous applications of different shapes and sizes of extruded material.

The Ring Blade air wipes are available in either anodized aluminum or 316L stainless steel for food or pharmaceutical applications and for high-temperature and corrosive environments.   The air wipes are made in two haves connected and can be opened and closed as necessary to address any bubbled products or other obstructions in the extrusion process.

The Nex Flow Ring Blade air wipe design incorporates the Coanda effect to efficiently entrain atmospheric air and system compressed air to convert energy lost as pressure drop and noise into useful flow and force, reducing the energy needed for any drying application compared to older technology.  Exhaust noise from compressed air is also reduced.

The airflow from the air wipe exists at a 30-degree angle toward the extruded material being passed through the air wipe.  Because of the amplified airflow, the total number of air wipes required can sometimes be reduced in multiple air wipe applications.

Where old technology may have required four units, sometimes only three Nex Flow air wipes would be needed, reducing energy costs further.   It is essential to have the inside diameter of the air wipe close to the surface of the maximum cross-sectional distance passed through the unit.

This is because the point force decreases as you are further from the target of the air.   Sometimes multiple diameters or cross-sectional areas are desired to pass through a given size, and a small part may be dried with a large internal diameter air wipe.   In this instance, the air gap can be increased to increase the overall force, which will also increase air consumption.

Discussing this with a Nex Flow application engineer for the best solution is best.

The Nex Flow design allows the air wipe to be used on add shapes, from rectangular extrusions such as window profiles to EPDM rubber trim used in the automotive industry. The smaller the extrusion diameter, the faster the extrusion speed tends to be.  Wire drawing, for example, can be extremely fast.    Nex Flow designs consider these high speeds in their design.

The smallest practical size to date is a Ring blade air wipe with an inside diameter of 3/8ths inch.  This is a typical size and the ½” version in wire drawing.   If a part is highly complex with tight channels that are hard to reach, Nex Flow-engineered air nozzles can be used before the air wipe to blast out moisture from those tight spots, and then the air wipe can quickly dry.

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