Tag: Air Amplifiers

Using Compressed Air Amplifiers for Cooling in Industrial Applications

Air Amplifiers, as explained in this article below from 2018, are the most popular products used for cooling for the reasons explained. One note to an ad is that cooling can be accelerated by adding shims to open up the gap in Fixed Air Ampfliers like the FX series or the Adjustable Air Amplifiers. They work so well because the air’s high velocity cuts through the boundary layer of the hot part, removing the heat quickly. The compressed air also has some cooling effect as it leaves the amplifier and goes to atmospheric pressure, creating a slight temperature drop. These products have even been used to “dehumidify” or remove moisture from surfaces as the blowing air absorbs surface moisture.

In many industrial applications, compressed is, or fans, are used to cool very hot parts. Compressed air will cool much faster than a fan, take up less space, and use more energy. This is important if the manufactured part is costly, and improved throughput will improve profitability.

One way to reduce that energy cost significantly is to use air amplifiers or air movers. Air Amplifiers are generally sized from 3/4″ to 8″ in outlet diameters. The most common size for cooling is from 1-1/4″ to 4″. This is because the larger the air amplifier, the more efficient it is for “amplifying” the flow, although small 3/4″ units are used to cool small parts. They work by drawing in atmospheric air from the back of, into, and then through the air amplifier.

Some companies use air-amplifying air nozzles – some which are made up to as much as 2″ in size. However, they amplify airflow by drawing in from the front around the nozzle exhaust instead of through the unit. So they will not amplify as much; with less mass flow, they will use significantly more energy than an air amplifier and produce more noise.

So when cooling very hot parts is necessary, consider using air amplifiers over air nozzles and fans.

Nex Flow® Air Products are specialists in using compressed air for blow-off, cooling, and moving and can assist in evaluating the optimum solution for cooling applications.

Pneumatics vs Hydraulics

With the advent of the Covid 19 pandemic, there has been an acceleration toward automation. Packaging solutions and advances have also become important. Pneumatics plays a very large part in both automation and packaging as outlined below in the blog

Part of pneumatic technology is the use of compressed air for blowing, moving and cooling. The rugged nature and general low cost of compressed air products for these applications as well as the extremely low level of maintenance required have become more important criteria where downtime and maintenance costs have also risen dramatically especially when compared to more complex and expensive capital cost alternatives.

Pneumatic and hydraulic systems have many similarities. Both pneumatics and hydraulics are applications of fluid power. They each use a pump as an actuator, are controlled by valves, and use fluids to transmit mechanical energy. The biggest difference between the two types of systems is the medium used and applications. Pneumatics use an easily compressible gas such as air or other sorts of suitable pure gas—while hydraulics uses relatively incompressible liquid media such as hydraulic or mineral oil, ethylene glycol, water, or high temperature fire-resistant fluids. Neither type of system is more popular than the other because their applications are specialized. This article will help you make a better choice for your application by describing the two types of systems, their applications, advantages, and disadvantages. The load or the force that you need to apply, the output speed, and energy costs determine the type of system you need for your application.

What is Pneumatics?

Pneumatics is a branch of engineering that makes use of pressurized gas or air to affect mechanical motion based on the working principles of fluid dynamics and pressure. The field of pneumatics has changed from small handheld devices to large machines that serve different functions. Pneumatic systems are commonly powered by compressed air or inert gases. The system consists of interconnected set of components including a gas compressor, transition lines, air tanks, hoses, standard cylinders, and gas (atmosphere). The compressed air is supplied by the compressor and transmitted through a series of hoses. The air flow is regulated by manual or automatic solenoid valves and the pneumatic cylinder transfers energy provided by the compressed gas to mechanical energy. A centrally located and electrically powered compressor powers cylinders, air motors, and other pneumatic devices. Pneumatic systems are controlled by a simple ON/OFF switch or valve.

Most industrial pneumatic applications use pressures of about 80 to 100 pounds per square inch (550 to 690 kPa). The compressed air is stored in receiver tanks before it is transmitted for use. The compressors ability to compress the gas is limited by the compression ratios.

Applications

Pneumatic systems are typically used in construction, robotics, food manufacturing and distribution, conveying of materials, medical applications (dentistry), pharmaceutical and biotech, mining, mills, in buildings, and tools in factories.  Pneumatic systems are primarily used for shock absorption applications because gas is compressible and allows the equipment to be less susceptible to shock damage.

Applications of pneumatic systems include:

• Air compressors
• Vacuum pumps
• Compressed-air engines and vehicles
• HVAC control systems
• Conveyor systems in pharmaceutical and food industries
• Pressure sensor, switch and pump
• Precision drills used by dentists
• Air brakes used by buses, trucks, and trains
• Tampers used to pack down dirt and gravel
• Nail guns
• High pressure bank’s drive-teller tubes
• Manufacturing and assembly lines
• Pneumatic motor, tire, and tools

Advantages and Disadvantages of Pneumatics

Pneumatic systems are selected above hydraulic systems because of the lower cost, flexibility, and higher safety levels of the system. Pneumatic systems are best suited for applications which require no risk of contamination because they offer a very clean environment for such industries as biotech, dentistry, pharmaceutical, and food suppliers.  Since they use clean, dry, compressed air, the system can quickly convey items. The straight and simple design prevents clogging and reduces maintenance. Pneumatic systems are easy to install and portable. They are reliable and has an initial low setup cost because they operate on comparatively low pressure and inexpensive components that reduces operation costs.

No container is required to store the air that will be compressed because it is drawn from the surrounding atmosphere and filtered (optional). The entire system is designed using standard cylinders and other components. The air or gas used in a pneumatic system is typically dried and free of moisture so that it does not create issues to internal components.

Pneumatic systems provide rapid movement of cylinders because the air compressor flow rates. Air is very agile and can flow through pipes very easily and quickly with little resistance. Pneumatic systems are available in a wide variety in very small sizes.  The pneumatic systems are clean and do not pollute because any exhaust is released into the atmosphere. The Pneumatic system is more agile because if the system needs to change directions, the simple design and control allows operators to update the system quickly without environmental impact.

Pneumatics are cheaper than hydraulic systems because air is inexpensive, plentiful, easy to obtain, and store. Pneumatic systems generally have long operating lives and require little maintenance because gas is compressible, and the equipment is less subject to shock damage. Unlike hydraulic systems that use liquids that transfers force, gas absorbs excessive force.

Safety is an important advantage of choosing Pneumatic systems.  Since Pneumatic systems run on compressed air, there is very little chance of fire compared with explosion or fire hazard of using compressed hydraulic oil. It is also maintenance free since there is little need to replace filters.

It is essential to determine the amount of force required for your application because not as much force is created with pneumatic systems as with hydraulic systems. Pneumatic systems do not offer the same potential force as hydraulic systems so they should not be used for applications that require lifting or moving heavy loads.  Compressed air experiences air pressure fluctuations, so that movement can be jerky or spongy at times while moving or lifting loads. A larger cylinder is needed to produce the same force that a hydraulic ram can produce. In terms of energy costs, pneumatic systems cost more than hydraulics because the amount of energy lost through heat produced while compressing air. Another significant concern about pneumatic systems is the noise that is created. If used, it is the responsibility of the owners to protect their workers from hearing loss.

What is Hydraulics?

Hydraulics is used for the generation, control, and transmission of power using pressurized liquids. It is a technology and applied science involving mechanical properties and use of liquids. Hydraulic systems require a pump and, like pneumatic systems, uses valves to control the force and velocity of the actuators. Industrial applications of hydraulics use 1 000 to 5 000 psi or more than 10 000 psi for specialized application. The word hydraulics originates from Greek words hydor – water and aulos – pipe. The following equipment is required for a hydraulic system: hydraulic fluid, cylinder, piston, pumps, and valves that control the direction of flow, which is always in one direction.

Hydraulic systems, unlike Pneumatic systems are often large and complex.  The system requires more room because a container is required to hold fluid that flows through the system.  Since the size of the system is larger, it requires more pressure; making it more expensive than Pneumatic systems. Due to their overall larger size and the incompressibility of oil, hydraulic systems can lift and move larger materials.   Hydraulic systems are slower because oil is viscous and requires more energy to move through pipes. During configuration and planning, if the factory or plant has several hydraulic machines, it is ideal to have a central power unit to reduce noise levels.

Applications

Due to the risk of potential hydraulic oil leaks from faulty valves, seals or hoses – hydraulic applications do not apply to anything that would be ingested – such as food and medical applications. They are used in a variety of everyday machine applications:

• Elevators
• Dams
• Machine tools: hydraulic presses, hoppers, cylinders, and rams
• Amusement parks
• Turbines
• Dump truck lift
• Wheelchair lift
• Excavating arms for diggers
• Hydraulic presses for forging metal parts
• Wing flaps on aircraft
• Hydraulic braking system in cars
• Lift cars using a hydraulic lift
• Jaws of life

Advantages of Hydraulics

Hydraulic systems are more capable of moving heavier loads and providing higher forces due to the incompressibility of liquids. Hydraulic systems do many purposes at one time, including lubrication, cooling, and power transmission. Hydraulic powered machines operate at higher pressures (1 500 to 2 500 psi), generating higher force from small-scale actuators. To effectively use a hydraulic system, it is essential to pick an appropriately sized component to match the flow.

Hydraulic systems are larger and more complicated systems.  Liquid, such as hydraulic oil is viscous and requires more energy to move. A tank is also required to store the oil from which the system can draw from when the oil is reduced.  The initial costs are higher than Pneumatic systems because it requires power that needs to be incorporated into the machine.

Any leaks in a hydraulic system can cause serious problems. This system cannot be used for food applications due to high risk of hydraulic oil leaks from faulty seals, valves, or burst hoses.  Appropriate plumbing procedures, preventative and regular maintenance, and having the correct materials on hand to minimize potential leaks and to quickly remedy any issues need to be in place at each site. In conclusion, pneumatic devices are best suited to execute low scale engineering and mechanical tasks while hydraulic systems are best for applications that require higher force and heavy lifting.

Summary:
In general, it is a good rule of thumb to use hydraulic systems primarily for heavy lifting applications such as the jaws of life, elevators, hydraulic presses and arms in heavy equipment, and wing flaps for airplanes because these types of systems operate at higher pressures (1 500 to 2 500 psi), generating higher force from small-scale actuators. When it comes to moving or manufacturing products, especially food or pharmaceutical, it is recommended to use pneumatic systems because there is no chance of contamination due to burst pipes or oil leaks. Nex Flow Air Products Corporation manufactures compressed air products for blow off, industrial cooling (Vortex Tubes), air operated conveying, and air optimization designed to reduce energy costs while improving safety and increasing productivity in your factory and manufacturing environments.

Engineered air jets, air knives, air amplifiers, and air nozzles are examples of blow off products manufactured and sold by Nex Flow. They are safe because they meet OSHA noise and pressure requirements. Air Amplifiers are recommended for purging tanks, venting fumes, smoke, lightweight materials from automobiles, truck repair, or from other confined spaces. These products are also used to clean and dry parts, remove chips, and part ejection. They can also be used as effective tools for your manufacturing environment.

Vortex tube industrial cooling applications converts compressed air into very cold air for spot cooling.  Nex Flow provides Vortex Tubes and Cabinet Enclosure Coolers. These products are ideal for use in high temperature and harsh environments. These products are especially ideal for use in high temperature and harsh environments. They also provide smaller vortex tube operated mini-coolers and vortex cooling for tool cooling systems. These systems can provide extremely cold temperatures without the use of refrigerants, such as CFCs or HCFCs.  Industrial vortex tube powered cooling products are recommended for cooling gas samples, heat seals, data centers, electronic and electrical control instruments and environmental chambers.

Compressed air operated pneumatic conveyors are designed to move materials at high rates and over long distances. They are ideal for continuous or intermittent use since they are operated by an on/off switch and controlled by a regulator.  Our air operated conveyors are compact and have no moving parts. Nex Flow also provides fume and dust extractors, Ring Vac Operated conveyors and an X-StreamTM Hand Vac system. Air operated pneumatic conveyors are primarily used for conveying materials for applications where vacuum force is required to move objects over long distances at high speeds. These devices have an on/off switch to enhance safety. It uses compressed air, not electricity, so there is no explosion hazard. The Nex Flow Ring Vacs are made of anodized aluminum or stainless steel. They are designed to transport or vent a wide variety of lightweight products, raw materials, or fumes from one place to another in your factory. For high temperature and corrosive applications, regular and high temperature stainless steel is available. When moving food and pharmaceutical products, 316L Stainless Steel pneumatic conveyors are used. The specially design non-clogging model XSPC air operated conveyors are easy to install and use, compact and portable, and maintenance free.

The systems offered by Nex Flow optimize compressed air system operations because of efficient design.  The systems can be easily turned on and off so that the compressed air is used only when needed. The products do not have high maintenance costs and are light weight. System optimization can be achieved with the compact sound meter, ultrasonic leak detector and PLC flow control (PLCFC) system for compressed air, which uses photoelectric sensors to turn on the air when the target passes the sensor and to turn off the air when it leaves the sensor or can be set by time. This device can be used for dust and debris blow-off, part drying system, cooling hot parts, and cleaning parts before packaging. Nex Flow offers various accessories that are integrated into pneumatics systems to increase the efficiency of compressed air conveying products and systems. Some accessories include nozzles, mufflers, filters, mounting systems and static control for blow off of dust and debris from statically charged surfaces.

Nex Flow pneumatic products reduce noise, enhance factory safety, and provide excellent venting, cooling, and blow-off solutions. Compressed air conveying systems provides instant response times and are the most efficient and effective way to convert pressure into useful flow.  The cost-effective pneumatic conveying systems provided by Nex Flow are simple, light weight, compact, reliable, and easy to install and use. Since there are no moving parts, pockets or angles to collect debris, moisture, or water, the maintenance costs are minimal. Expect the best from Nex Flow technicians, who are trained to help you determine the best solution for your application.

A Ring Vac is a compressed air operated conveyor that works on a Venturi principle.  Compressed air is input into the Ring Vac internal plenum chamber and exits from several holes drilled around the inside diameter of the unit in the direction of flow out of the unit creating a vacuum at the inlet end. The holes are designed to minimize compressed air use and optimize the creation of the vacuum.   The air flow outlet is amplified approximately 6 times that of the inlet compressed air. Unlike “coanda” profile air operated units called “air amplifiers” the air operated conveyor device create a much higher vacuum and less air flow amplification. For this reason they are excellent for conveying products longer distances.   A pipe or tube is connected to each end of the unit. Material is fed into one end and exits at the other. How far vertically and horizontally can the unit convey depends on the physical size of the unit (vacuum decreases as size increases) and the nature (weight, size and shape) of the material conveyed.   

As for products to be conveyed they may be small particles, powders, larger materials and even gasses.  Venting can be a great application for Ring Vacs especially if the gasses are not clean as will be explained further.

Because these units use compressed air, they are not likely to be used to conveying tons of material.  Instead, they are best suited for primarily intermittent applications (or continuous applications where low pressure is needed such as in gas venting) and for capacities limited to under 15 pounds or 7 kg per minute. Within these limits however, Ring Vacs can effectively and economically replace electrically operated vacuum pumps in all sorts of applications and industries. Now, let’s look at its compatibility with different types of materials.

Compatibility with solids:  When conveying solid materials, the material in size should be no more than 50% of the size of the inlet diameter of the Ring Vac to avoid getting stuck.   An exception is, for example if a long (but thin piece) that will fit through the unit is fed into the Ring Vac. In that case, as with other materials, it will be drawn in and accelerated to a high speed and conveyed along the pipe or tube to which it is connected.   Standard Ring vac units are available in anodized aluminum, a more powerful version in hard anodized aluminum to handle more abrasive materials, and in 303/304 stainless steel for corrosive and high temperature applications and in 316L stainless steel for higher corrosive environments and for food and pharmaceutical applications such as in the conveying of capsules and pills. Ring Vacs may be manufactured out of special materials for conveying materials if the standard materials are not compatible.

Conveying powder:  Moving powder is easy with a Ring Vac but it’s the powder “exiting the unit that has to be dealt with. The powder leaves at a high velocity and when the powder exits and is collected, a large dust cloud can be created.  So whatever container it enters must be deep enough to contain the cloud. Using a fine filter to contain the cloud will not work because the back pressure caused by too fine a filter will negatively affect the conveying performance.  In one creative application, a stainless steel Ring Vac was used to convey seasoning from one vat to another to be mixed with other material. The seasoning was fine powder. On the vat where the seasoning was conveyed, the customer installed a “chimney” that was tall enough to contain the cloud created when the material went into the vat. At the top of the chimney was a “coarse” filter which allowed for the air flow to exit but enough to contain the seasoning.

Small Particles:  With small particles and also with powder, when the material is collected at the inlet side of the Ring vac (we restate that you need to attach some pipe or tube at the inlet end as well as at the outlet to collect the material for best performance), the material needs to “breathe” to be drawn into to conveyor.  So placement of the inlet tube or pipe and design is important. But once inside the unit they are easy to convey.

Large Objects: The main thing to note in conveying larger materials is that the size or dimension of the object should not be greater than 50% of the inside diameter of the Ring Vac to avoid getting stuck. If the materials are smaller than half the inside diameter – even relatively heavy objects such as screws and nails can be conveyed effectively. 

Compatibility with Gas: Gas venting is one major application.  Air Amplifiers can also be used but there is one major advantage of using Ring Vacs and that is the intrinsic design.  When air amplifiers convey gas, if the gas is dirty, material can deposit onto the “coanda” profile and after some time negatively affect performance and even stop working when the buildup of dirt and debris becomes critical.   The design of the Ring Vac is such that the chance of dirt depositing over the air exit holes is greatly minimized. Also, when using the unit for venting applications you require very little air pressure to move the gasses, even as low as a few PSIG with some applications using only 1 PSIG if conveying a short distance.   It is with materials that one has to be careful in moving gasses. Some gasses may be highly corrosive, and sometimes you end up dealing with very high temperatures. For example, high temperature stainless steel units are used to vent hot sour gas and sometimes must handle up to 1200 oF. (649 oC).   Special ones made of Teflon have replaced vacuum pumps in scrubbers and use very low input pressure to operate, eliminated high maintenance costs associated with electrically operated vacuum pumps for the same application.   Special flanged versions with different materials have been made for many venting and gas conveying applications in a variety of manufacturing such as battery production.

Compatibility with Liquid: Ring Vacs have been used with limited success in liquid conveying and the smaller sizes may be used.  They are not really designed for liquid handling and not an application that is encouraged. However, for the smaller sizes (1” and smaller) and for limited distances, they have, and are being used.

Summary: Whether Ring vac are used for conveying solid material, large or small, or powders or for venting gasses, they are economical for smaller capacities outlined above and especially ideal for intermittent applications in the case of solids, or low pressure applications in the case of venting. Like nozzles, air knives or any other compressed air accessories they are virtually maintenance free with no moving parts.   They can be made out of a variety of materials, special sizes and shapes have been designed and manufactured for all types of industries – plastics industry for hopper loading, natural gas transmission for venting compressors, semiconductor industry for gas venting, food industry for conveying ingredients, etc.   In every case the more costly alternative was vacuum pumps. It would be good to check your operation as to where vacuum pumps are now used to evaluate whether a Ring vac can provide a lower cost, more efficient, alternative.

Both Air Amplifiers (especially the FX40 fixed unit and 40002 adjustable unit) and Ring vacs (of various sizes and materials) are used for gas venting applications. In fact, we have manufactured Teflon Ring Vacs for moving gasses in scrubbers to eliminate the maintenance required with vacuum pumps.

Sometimes the Air Amplifiers are first considered for venting because they use the Coanda effect which moves a large volume of gas. They are excellent in moving atmospheric air for example, in venting an enclosure or chamber in emergencies. 

However, if the gas in question is dirty in any way, and/or the material needs to be moved a greater distance, then the Ring vac is a better choice. 

First, an Air Amplifier is limited to about ten feet (3) meters of conveying. It is more sensitive to back pressure than a Ring vac so the distance is limited. Also, the longer the distance, the less the “amplification”. The Ring vac is much less sensitive to back pressure and can move any vented gas much farther with less back pressure effect. It is used extensively in venting the crank cases of gas transmission compressors for example, eliminating the maintenance and regular checks needed on electrically operated vacuum pumps. Air Amplifiers also need at least 80 PSIG (5.5 bar) pressure to work well in venting while Ring vac may do the job with even small pressures of well under 20 PSIG (1.4 bar) minimizing energy use.

FEATURED PRODUCTS

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Second, if the gas being vented contained any particulate that may condense out or in any way deposit inside the conveying unit, this can be problematic with Air Amplifiers. The Coanda profile which makes them operate needs to be relatively clean. If a deposit builds up over time, the Air Amplifier may no longer vent well and perhaps even stop working. The Ring vac however, operates differently and the holes in the “generator” of the Ring vac is well insulated against the movement of the gas and any buildup would take much longer to occur, if at all.

Third, Ring vac units are generally less costly than Air Amplifiers and special versions are easier to make to adapt to special applications. If the particular application requires it, special materials can be used, special flanges can be provided or other attachment variations, and other things can be added to suit the customer requirements.

The above explanations seem to favor the Ring vac but it all depends on the specific application. Always speak to a Nex Flow representative for advice on the most appropriate choice.

The Nex Flow Difference: Why we treat our materials differently?

Nex Flow Air Products Corp. sets itself apart from its competitors by doing a few things differently with the materials that we use in manufacturing our products. While some producers are actually quite similar in product as to how they deal with material, we stand out in four specific areas as to what we do with the materials of manufacture. Differences for Nex Flow are as follows:

1. Anodized aluminum parts
2. Powder coated parts
3. No Plastic in our vortex tubes
4. We do not mix aluminum and stainless steel in our vortex tube packages

Anodized Aluminum parts

We make it a point to anodize our aluminum air knives, amplifier, air jets, air wipes and air operated conveyors.

It is actually much easier (and certainly less costly) to produce these items without anodizing due to the importance of efficient aerodynamic design. When the products are anodized the surface changes, even if the change is very small, it makes it more difficult to keep a flat part flat (i.e. air knives). But, we CAN do and we do it because of the value the anodizing adds benefits to the products.

Anodizing helps guard against the effects of the factory environment on the aluminum. Unprotected aluminum will form a powdering while oxide over time. Anodizing keeps the product looking better and longer even when using dissimilar metals in assembly, stainless shims, stainless screws, with aluminum bodies, it protects the accessories from even minor effects of cathodic corrosion.


Cathodic corrosion can occur in a highly humid environment or if the parts get wet. Dissimilar metals can act like a battery where the more active metal can corrode unless there is some form of protection. You can see this effect, for example, with rust around screws used on some buildings or machines because the screws are of one material while the metal it is screwed into is another. When paint wears away, it leaves unprotected metal that is more electrically “active” than the metal in the screw. By anodizing and protecting our product, Nex Flow ensures that our accessories will last longer and look better over time.

Powder Coated parts

Some of our cast zinc parts, specifically our Air Edger flat jet nozzles and cast Fixed X-Stream Air Amplifier, also have powder coating. It provides a much better finish and look to the product and again, extra layer of protection from the factory environment. Powder coating is an excellent protection in a factory environment. Powder coating parts adds intrinsic value to the products to the betterment of the customer providing a product that is longer lasting look better through time.

No Plastic in Vortex Tubes

Most manufacturers of vortex tubes use injection molded plastic “generators” which are used in the unit to initiate the compressed air spinning effect. Nex Flow machines their “brass” generators for that purpose instead of plastic. While plastic would be much less costly, brass offers a few advantages. Injection molding plastic will have some variations in production, especially as the mold wears out. By machining the metal generators we have much greater consistency with the parts which translates into much greater consistency in performance from one vortex tube to the next. Vortex tubes consist of several parts and of course, each part has a certain tolerance in manufacturing. Nex Flow has very tight tolerances on each part and the generators especially require very tight tolerances. The more pieces involved in assembling a part, the more the cumulative effect on the overall variation in tolerance and therefore performance since the operation of all Nex Flow products are based on aerodynamic shapes.

As the generator is such a critical component in a vortex tube, we recognize the need to use metal instead of plastic. Another advantage of using metal, in our case brass, instead of plastic is that plastic can possibly crack over time. If the compressed air supply is dirty the generator can also build up dirt and engrain itself, hence requiring replacement. The metal ones we use are easily cleaned. Sometimes vortex tubes or their packaged versions are used in very hot environments so the parts must be able to hold up in high temperature areas, especially when not operating. In these cases even competitive units replace their plastic generator with metal. Nex Flow vortex tubes and many of their packages are therefore more flexible in the environments where they can be used. While competitors would charge extra for a special product, our standard product can generally be used instead.

We do not mix Aluminum and Stainless Steel

Our vortex tube packages include tool coolers, mini coolers, adjustable coolers, panel coolers, etc. Of particular importance is the materials used in a panel cooler used for cabinet enclosure cooling and camera cooling. Many manufacturers will use a stainless steel vortex tube packages as a control panel cooler using aluminum housing and attachments. While not a problem in relatively benevolent factory environments, it can become an issue in very humid area or in applications where they are used in wash down conditions. Cathodic corrosion can occur described earlier with dissimilar metals with air knives. On one visit to a customer there was actually a competitive vortex tube cooling system with a big hole on the side of the assembly. Cabinet cooling applications are very critical because you do not want any possibility for moisture getting into the control panel. This is the reason vortex coolers should have the proper approvals to insure this does not happen (such as Underwriters Laboratory testing and approval).

Cabinet Coolers are essentially vortex tubes with a cover and some system to prevent moisture from getting inside of the cover and possibly then into the cabinet. This cover was aluminum and the vortex tube another material. The environment was a relatively wet environment, so over time cathodic corrosion cause the aluminum to corrode and create a hole in the protective cover. Thus, creating a potential risk for water to get into the electrical cabinet. It is for this very reason (preventing cathodic corrosion) that Nex Flow only has stainless steel covers for their stainless steel vortex tubes.

Similarly with all other packages systems, whether they are tool coolers or adjustable coolers, the packages are made with stainless steel only and not a mixture of stainless steel and aluminum.

It’s a Wrap

These are some of the reasons why Nex Flow treats their materials differently. While some of these “differences” in material handling and treatment can be more costly from a manufacturing point of view, they do offer significant added value to the products and a benefit to the customer, and still with a very competitive price.

Wind tunnels are large tubes with air moving inside. These tunnels are used to test models of aircraft or other flying objects on their actions in flight. These models are scaled down versions of actual objects that will be built. Researchers and institutions around the world like NASA, uses wind tunnels to learn more about how an aircraft and spacecraft will fly. But it is not just flying machines that are tested. These Wind chambers are also used to test how an automobile shape, or windshield design will behave in environments with strong winds. Aerodynamics is the study of the flow of air or gases around an object in motion. Essentially these tunnels are hollow tubes with controllable fans at one end to test objects aerodynamics ensuring safety and performance of machines.

Airplane builders use NASA wind tunnels to test new airplane designs.
Credits: NASA

Frank H. Wenham (1824-1908), along with his colleague John Browning, invented the wind tunnel and built the first one in 1871. He described it as “a trunk 12 feet long and 18 inches square, to direct the current horizontally, and in parallel course.”  As a British marine engineer he studied the problems of human flight and had many publications. He also made a huge influence in the development of aeronautics. Their experiments showed that high aspect ratio wings – long and narrow—had a better lift-to-drag ratio than short stubby wings with the same lifting area. Wenham may have been the first scientist to use/coined the word “aeroplane”.  Aviation writer Carroll Gray says Wenham’s work may have been an important influence to the Wright brothers.

As mentioned above, wind tunnels typically use powerful fans. But – it is possible to use Nex Flow compressed air operated Air Amplifiers instead of fans for a miniature wind tunnel. To get the system to work, the gap setting on the Air Amplifiers will have to be increased to approach the power needed for testing even a very small object. Although there are limitations to using compressed air for wind tunnel emulation – they do offer some advantages like having a lower noise level and their ability to be combined with vortex tube technology for testing at sub-zero temperatures.

Powerful fans overcome back pressure created by the length and overall volume in the tunnel. Compressed air amplifiers however cannot be “revved up” like a motor and are subject to this back pressure limiting the length and volume of a tunnel where it can be used. However for very light and small objects, it is conceivable to use an Air Amplifier to operate a miniature wind tunnel.

Air Amplifiers take compressed air that is consumed and converts the pressure normally lost as pressure drop and noise into high velocity and high laminar flow.  With fans you can control this velocity and flow by making the fan turn faster or slower. With Air Amplifiers you have some limited control with input pressure but in a much more narrow range which should suffice for a small miniature tunnel. A common setup at exhibitions is to attach an Air Amplifier to a stand and have the amplified airflow support a beach ball which can be held a few feet above the vertically aimed Amplifier. The object tested in an Air Amplifier operated miniature wind tunnel would have to be in the low weight range of a beach ball to be useful. A powerful compressed air operated engineered nozzle, or a series of engineered air nozzles might be paced at one end of a miniature wind tunnel for more force. After a short distance, the combined airflow could produce enough velocity and flow to be useful for testing small, light objects.   One advantage of both using compressed air amplifiers or laminar nozzle is the lower noise level than you would get from a powerful fan.

Vortex tube technology however, does offer one advantage for a special type of wind tunnel.  A vortex tube is a device which takes compressed air and divides it up into a hot and cold stream.  This cold stream of air flow can go to very low, sub-zero temperatures. Vortex tube commercially are available in air consumption ranges of 2 to 150 SCFM. However, there is no reason that a vortex tube cannot be made much larger to consume several thousand SCFM. In some research applications for wind tunnels it is necessary to study aerodynamics at sub-zero temperatures (i.e. the behavior of military aircraft in arctic or subarctic conditions). A much larger vortex tube consuming one thousand SCFM or even more can produce very cold temperatures of -40 ˚C and even colder if the compressed air supply is cooled further. While it would seem to be uneconomical to use such high volumes of compressed air, that high energy cost is offset by the fact that you do not have to cool the air to the sub-zero temperatures required for testing. Also, the efficiency in the production of the cold temperature actually goes up as you increase the size of the vortex tube. Let’s presume you have 10,000 SCFM of compressed air supply.  With vortex tubes the temperature drop increases (you get colder temperatures) the more air you exhaust at the “hot end”. So if only 30% (3000 SCFM) goes out the cold end to get that -40 degrees Celsius. The cost of cooing 3000 SCFM of a fan produced air flow to that cold temperature using a more traditional means of cooling will be very high. You also will be using refrigerant which will be costly, and need maintenance. In using a special vortex tube you only have the compressors and the wind tunnel taking the flow, at the low temperatures you want. This minimizes any maintenance involved. It is actually a very simple system.

So while there are certainly not a great deal of applications where a wind tunnel is needed that produces such low sub-zero temperature airflow, there are certainly enough when dealing with some military and space equipment applications where aerodynamic tests results under extremely low temperatures are required.  In this case, using a special large vortex tube is a possibility. Such special wind tunnel has been built in the past with very large vortex tube design.   

For unique applications such as the above – Nex Flow has experience in special vortex tube design. Some years ago a two meter long vortex tube was developed for an application (not a wind tunnel however) which used natural gas as the medium instead of compressed air. The parameters of the application had to be addressed to develop the optimum design and the supply gas was at very high pressure. The application remains proprietary but it does indicate that vortex tube technology can be adapted and made effective and economical for special applications where cold temperatures or overall cooling is necessary and where using traditional cooling would not be as effective or economical.

So for wind tunnel applications, Air Amplifiers (and even Engineered Air Nozzles or jets) can apply to miniature wind tunnel for small and lightweight objects. If the wind tunnel requires sub-zero temperatures, vortex tube can be integrated as part of the system. Do note that as these are two different things entirely, you connect a vortex tube to an air amplifier

FEATURED PRODUCTS

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Using Compressed Air in Packaging

Compressed air is safe, reliable, and used in packaging products. The compressed air systems move materials from one area of the factory to another, perform blow-off, part drying, and align products for packaging. Bakeries use compressed air for blow-off applications, while others use compressed air to clean containers before filling them with products.  Compressed air technology is also used to cut, sort, shape, and convey products, such as food, from one location to another in a factory.

Cartons are also formed, filled, and sealed using compressed air. The quality of compressed air can vary widely depending on its application. The food industry requires the highest level of safe, clean compressed air to handle and package goods. Pharmaceutical industries also require more stringent clean air than other industrial applications because they are either ingested or injected.

Clean, high-quality compressed air is required in pharmaceutical and food packaging to ensure consumer safety and prevent product contamination. It is essential to have either no contact with the product or contact using pure air to avoid product recalls, damage to brand reputation, or litigation. Pneumatic systems are recommended because there is no chance of leaking oil as in hydraulic systems.

Pneumatic systems do not pollute or release contaminants into the atmosphere, so they are especially useful for packaging food products. These systems have no moving parts, so there is less maintenance and downtime compared to other systems.

Using Compressed Air in Packaging

Clean compressed air is essential for food and pharmaceutical processing and packaging operations. Compressed air must be purified, especially when the product is consumed.  Compressed air conveyors are the best technology to ensure safe food quality. Contaminants include spores, solid particulate, vapors, and moisture. Oil is often not an issue with compressed air conveying systems, unlike hydraulic systems, which use oil as a medium.

To stop microorganisms and fungi growth, the dew points of air at line pressure must be -25 degrees Celsius (-15 degrees Fahrenheit). Standards have been developed that state very fine filtrations to prevent particulate and oil from contaminating food products.

How does Compressed Air Keep Products Dry and Free of Contaminants?

Equipment performance is only as good as the quality of air. Any atmospheric air contains some moisture and dirt. No matter how small the contaminants are initially, they are concentrated when the air is compressed as the air heats, its ability to hold water vapor increases. The vapor condenses into liquid when the air begins to cool as it travels downstream. Maintenance by plant operators can remove liquid, particles, and contaminants. Air dryers are installed to reduce moisture.

They lower the dewpoint of the compressed air to prevent water droplets from forming downstream. There are four types of dryers: Refrigerated, chemical, regenerative, and membrane or mechanical. Mechanical filters work with compressed air dryers to remove contaminants and water. There are three types of filters: Particulate, coalescing, and adsorption.

After the appropriate filter has been added to the conveying system to ensure that the compressed air equipment does not introduce contaminants, equipment that is used to blow off products before packaging is added, examples of this type of equipment include engineered nozzles and air knives. They conserve compressed air by using the Coandă effect to entrain surrounding air along with compressed air to create a high-flow velocity stream of air.

What are some things to remember when using Compressed Air Products for packaging?

If used as intended, compressed air will not generate biological, chemical, or physical hazards while packaging goods. The manufacturer is responsible for producing final products that are sanitized and free of contaminants such as oil, microorganisms, particulate or dust. Manufacturers that use the compressed-air system must carefully consider productivity and production costs against safety.

Compressed air used in packaging will often come into contact with the product. “Contact Application” is defined in the British Compressed Air Society (BCAS)/ British Retail Consortium (BRC) code of Practice for Food Grade Air code as “the process where compressed air is used as part of the production and processing including packaging and transportation of safe food production.”  This means that packaging and moving products with compressed air is a contact application.

Other examples of compressed air contacting the product include blowing off the water after washing a product and before packaging, cooling a product to increase line speed, and blowing off excess ingredients (such as sugar) before cooking. Non-Contact Application is “the process where compressed air is exhausted into the local atmosphere of the food preparation, production, processing, packaging or storage.”  Non-contact applications can be categorized into 2 additional sub-categories (high risk and low risk).

Using Compressed Air in Packaging

When designing a compressed air system for conveying, it is important to use filters and air purifiers to ensure compliance with various safety and manufacturing standards. The BCAS/BRC Code of practice recommends testing the machinery installation twice a year for contaminants such as microorganisms, particles (dirt and dust), humidity, and oil contamination. Refer to this article to learn more about the requirements in the food industry or the standards in the pharmaceutical industry.

With regards to filtration, a centralized air drying and filtration system should suffice if the pipes are relatively new in the facility. However – if the pipes are polluted or hard to clean – it is better to have both a centralized filter as well as a decentralized filter installed upstream of the point of use. New or cleaned pipes are also recommended of zinc-plated steel for food applications, V2A/V4A, compressed air-approved plastic, or aluminum.

How does it work?

The Packaging industry includes a wide variety of materials and products since almost every manufactured product is packaged: toys, food, soft drinks, beverages, cigarettes, cosmetics, brushes, kitchen accessories and more. All the products move down the assembly line before packaging. The packaging process consists of transportation lines made of pipes or ducts to carry a mixture of products and materials along a stream of air.

The pneumatic conveyor system consists of interconnected transition lines, hoses, cylinders, a gas compressor, standard cylinders, and gas (atmosphere). The compressor generates the air flow and transmits the material through a series of hoses. Manual or automatic solenoid valves control the air flow—a centrally located and electrically powered compressor powers cylinders, air motors, and other pneumatic devices. Pneumatic systems are controlled by a simple ON/OFF switch.

There are three conveyor systems that generate high-velocity air streams: a suction system/vacuum system, a pressure system, and a combined system.

A suction or vacuum is used to move light-free-flowing materials. The system operates at 0.5 atm below atmospheric pressure.

A positive pressure compressed air conveying system is used to push material from one point to another.  This type of conveyor operates at a pressure of 6 atm or more.

The combined suction/pressure conveying system is used to convey material from several loading points (suction) to deliver to several unloading destinations (push).

What are some Nex Flow products applied to packaging items?

Pneumatic systems are highly recommended when manufacturing, moving or packaging any product that will be digested or inserted in a living organism, such as food or pharmaceutical goods, since there is no chance of contamination due to burst pipes or oil leaks. Nex Flow manufactures compressed air products that help companies to package goods by supplying machines used for industrial cooling (Vortex tubes), part cleaning, drying, and blow-off, and air-operated conveying before packaging.

Nex Flow engineered air optimization design improves safety while increasing manufacturing and packaging productivity and decreasing energy costs.  The air-operated conveyor systems sold by Nex Flow can replace traditional conveyor belt systems, which have higher operational costs because they need to be regularly maintained.

Spot Cooling

Nex Flow pneumatic products provide the best spot cooling and blow-off solutions for materials before packaging.  Vortex tubes convert compressed air into very cold air for spot cooling for industrial applications. Small vortex tube-operated mini-coolers and vortex cooling can provide extremely cold temperatures for spot cooling before packaging without refrigerants, such as CFCs or HCFCs.  Vortex tubes improve factory safety and reduce noise for workers in a manufacturing environment.

Blow-Off Products

Effective, engineered blow-off products manufactured and sold by Nex flow include air knives, air amplifiers, air jets, and air nozzles. These products are another example of how Nex Flow strives to improve the safety of manufacturing and factory environments because they meet OSHA noise and pressure specifications. Among many other applications, air amplifiers are used to clean and dry parts and remove chips and part ejection.

Air knives and nozzles are used to flip open and close the tops of boxes during packaging. Air blade ionizers effectively remove static that could trap the dirt while using plastic wrap for packages.

Conveying Systems

Compressed air-operated conveying systems move materials and products at high speeds over long distances.   Ring Vac Operated conveyors, and X-Stream Hand Vac are used for conveying materials where vacuum force is required to move products over long distances at high rates. Ring Vac Air operated conveyors were originally designed to help with bending and lifting goods. The speed of conveyors depends on the density of the materials (lbs./cubic foot), horizontal distance, and vertical lift.

A Ring Vac operated conveyor is a simple, low-cost solution to other pneumatic conveying systems. They are available in several materials depending on the application. Ring Vac operated systems are made of anodized aluminum or stainless steel. 316L Stainless Steel pneumatic conveyors are used when moving food and pharmaceutical products or packaging. It is available in regular and high-temperature stainless steel for high-temperature and corrosive environments.

The X-stream® Supreme Pneumatic Conveying System (XSPC) is an air-operated conveyor that uses compressed air for an efficient and power venturi action along the length of the non-clogging design.   The compressed air system is designed to transport or vent lightweight items and raw materials for packaging at high rates over long distances.

The cost-effective systems are ideal for continuous or intermittent use since they are operated by a simple on/off switch and are controlled by a regulator.  All Nex Flow conveyor systems are simple, easy to install and use, compact, portable, and maintenance-free.

Other benefits of compressed air-operated conveying systems are also reliable since there are no moving parts and low maintenance costs.  These systems have no angles to collect contaminants such as moisture, particulate debris, or microbiological growth. They are safe for any factory environment because the system is powered by compressed air and not electricity.

Mufflers, filters, mounting systems, and static control for blowing off dust and debris from statically charged surfaces are available through Nex Flow to improve factory production and efficiency in assembly and packaging goods.

Trust Nex Flow to provide the most efficient, reliable, maintenance-free compressed air solutions for packaging your goods so that they are clean and safe for your customers.

Using Compressed Air in Packaging FEATURED PRODUCTS

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• Our ability to hear is critical for much of our communication yet we don’t realize it until we lose or damage our ability to “hear”.
• High levels of noise can lead to permanent hearing damage and high vibration caused by noise can lead to a variety of significant medical conditions
• At lower levels, both noise and vibration can cause interference with our ability to hear and feel, such as reducing the ease of normal conversation and can be annoying, irritating and unpleasant
• For both noise and vibration there is generally a level below which no adverse reaction occurs
• There are also favorable responses to noise and vibration
• Individual responses to noise can vary significantly but there are consistent trends between noise level, measured in dB(A), and annoyance for the general public.

Nex Flow® manufactures compressed air operated nozzles, air knives and other blow off products with the above in mind.  The technology works by converting energy normally lost as pressure drop into useful blowing and cooling energy with noise reduction a by-product.  This by-product is very important as these noise level reductions can be 10 dBA or more.

Many production facilities put a heavy emphasis on the energy reduction from the technology but often fail to consider the importance of noise reduction.

As an example of just how much noise effect your well-being check out this article from THE ATLANTIC: https://www.theatlantic.com/magazine/archive/2019/11/the-end-of-silence/598366/

Galvanic Corrosion – What it is and how to prevent it?

Galvanic corrosion (also called bimetallic corrosion) is an electrochemical process in which one metal corrodes preferentially when it is in electrical contact with another, in the presence of an electrolyte.  This occurs in batteries for example where the cathode stays whole and the anode corrodes as the battery is working. Contrary to some believes – Galvanic corrosion does not only occur in water. Galvanic cells can form in any electrolyte, including moist air or soil, and in chemical environments. As an example, Over 200 years ago, the British naval frigate Alarm lost its copper sheeting due to the rapid corrosion of the iron nails used to fasten copper to the hull. The electrolyte in this case was salt water creating a galvanic cell.

In the case of the Alarm, the iron acted as an anode and was corroded at the expense of the copper which acted as the cathode. Just two years after attaching the copper sheets, the iron nails that were used to hold the copper to the ship’s underside were already severely corroded, causing the copper sheets to fall off.

Metals and metal alloys all possess different electrode potentials. Electrode potentials are a relative measure of a metal’s tendency to become active in a given electrolyte. When in the same environment, the more active a metal is likely it is to form positively charged electrode (anode) and the less active metal is more likely it is to form a cathode (negatively charged electrode).

The electrolyte acts as a conduit for ion migration, moving metal ions from the anode to the cathode. The anode metal, as a result, corrodes more quickly than it otherwise would, while the cathode metal corrodes more slowly and, in some cases, may not corrode at all.

The Nex Flow Difference Allowing Products to Last Longer than Competitors

While products such as air knives, air nozzles, air amplifiers, vortex tubes, etc. are not necessarily immersed in any electrolyte, if the environment is humid, or if the equipment is subject to wash down procedures, it is very possible that this type of corrosion can occur.  One example is mixing stainless steel and aluminum. There was one example where a competitive cabinet enclosure cooler was observed with a big hole on its side after some years of use. The stainless steel vortex tube inside combined with the aluminum housing, and the factory environment, over time caused the aluminum to act as an anode and started to corrode.

Nex Flow® takes certain steps and actions to prevent this from happening in their products allowing the products to last longer.  The first is to protect aluminum that is used, especially if combining it with steel or stainless steel. Our aluminum air knives for example – are anodized and as such have a protective coating to prevent an “electrical circuit” with the stainless steel shims used inside and the stainless steel screws used to hold the air knife together. In addition, the aluminum would tend to act as an anode anyway in an electrolytic environment and being so large compared to the stainless steel shim corrosion would be minimized. Regardless of whether galvanic corrosion would occur, the anodization also protects the air knife from any environment which bare aluminum is unprotected.  Similarly, Nex Flow anodizes all their aluminum parts – air knives, air jets, nozzles, air wipes and air operated conveyors such as the Ring vacs. Air amplifiers and flat jet nozzles which are aluminum zinc-cast are powder coated for longer life and also look better.

When it comes to vortex tube technology, such as cabinet enclosure coolers (panel coolers) and tool coolers, no aluminum is used. It is stainless steel with some brass internal parts. This works to ensure that you will not find any holes in Nex Flow Panel Coolers caused by galvanic corrosion ever. So when shopping for products to blow off, clean, move, and cool, look not only at the performance data, design and workmanship – all which are important of course – but also refer to the quality and type of material used in construction. You can also refer to this article on how to avoid galvanic corrosion. Remember that materials used and how they are put together does make a difference.

Air Amplification Explained compressed air-operated amplifiers presume to reduce compressed air use and lower noise levels in blow-off and cooling applications. The term air amplifier is normally applied to annular-shaped units (called Air Amplifiers or Air Movers).  However, the same technology used applies to air nozzles, air jets (which are essentially small Air Amplifiers), air knives (linear amplifiers), and some air wipe designs.  

They work using the Coanda effect, which essentially is an effect in which a fluid (liquid or gas) clings to a surface as it flows in a laminar flow.  You can see this effect by turning on the water tap in your kitchen at a low level, so the water flow is smooth. Put your finger just touching the flow, and it will bend the water flow as it slings to your finger.  The same thing occurs with a compressed gas like air.

To achieve the best use of this Coanda effect other factors need to be considered such as the volume of the chamber that the compressed air exits to minimize any turbulence inside the chamber and minimize pressure losses.  The number of and actual angles of these Coanda “angles” combined with internal designs where the compressed air is collected before exit determines the overall efficiency and performance of the compressed air used for blow-off. 

As this air bends, it creates a vacuum behind it drawing in surrounding atmospheric air. This “converts” the pressure that is normally lost as pressure drops and noise into the flow. This is important. Several things occur as this additional mass flow is drawn in and mixed with the compressed air. 

First, the overall force goes down because you mix with still (non-moving) atmospheric air. Secondly, the flow is dramatically increased because of this pressure conversion to flow. It is “converted energy” instead of “lost energy.” While the overall force goes down, overall kinetic energy remains high and laminar for some distance. 

This means that whatever blow-off energy is required, it can perform that operation at a greater distance from the exit of the air than if compared to an open pipe or tube. And, of course, because lost energy is recovered, the noise levels drop. So when we state that air amplification is free, it is quite true, but with the caveat that overall force will be lower, but velocity and flow will both be much higher, all due to the extended laminar flow. 

If air is blown with just an open pipe or tube, the exit creates a great deal of turbulence resulting in energy loss and high noise levels. This means that the force may be quite high near the exit, but it will dissipate quickly as you move away from the air exit.   

There are some situations where high pressure is required. In those situations, an air amplification nozzle or device may not meet that force, such as removing heavy mud baked onto a surface or breaking off scale waste from metal.  But the pipe used has to be close to the surface. However, except for those situations, air amplification technology certainly can be used instead, as the vast majority of applications where compressed air is used do not need the full high-pressure force of an airline.  

One suggestion to reduce energy and noise is simply to reduce air pressure for blow-off and even cooling applications. After all, a 20% reduction in compressed air pressure will reduce the compressed air energy by 10%. If you reduce the pressure to 30 pounds from 80 pounds per square inch, that would yield a 25% reduction in energy.  Noise will go down somewhat, but you will still have a great deal of turbulence at the air exit, and you will not get the “distance” for effectiveness that you would with an air amplifier.

But, even an air amplifying air nozzle will get anywhere from 30% to 40% or more energy reduction with the equivalent force, depending on the design of the air nozzle.  For example, older cone-shaped air nozzle designs will reduce energy by 30% and create very high flow and velocity, which is especially ideal for cooling applications. The Nex Flow Air mag design reduces energy by over 40% and works with a powerful force and high flow, and high velocity with the laminar flow at a very long distance, as well as noise reduction.  

The argument for that extra “free” energy from air amplification is therefore very compelling.

As was hinted at above, it is not just the flow profile and Coanda “angles” which affect performance.  It is the internal design of an air amplifier and how the compressed air behaves internally that is also important.  Minimizing internal turbulence is a major consideration in design. For example, you can take five different cone-shaped air nozzles from different manufacturers, test them side by side, and their performance and efficiency can vary by a wide margin. 

In this case, efficiency can be defined as the force produced at a set distance divided by air consumption. There is a design called a Laval nozzle, for example, that was developed to produce less noise and improve energy. However, the noise level improvement is not significantly noticed due to the noise frequencies obtained, and the distance of effectiveness appears to be limited because, to make this design work, the efficient exit of the force-producing airflow has to be contained by a rather inefficient series of air flows from slots around the Laval opening, offsetting any other improvements.  

The Coanda design combined with proper internal design appears to be the optimum methodology in air amplifier design.

Air jets are another example where the Coanda design makes a big difference.  Air Movers or large annual Air Amplifiers, if very small, are called Air Jets.  Most manufacturers of Air Jets have one Coanda angle to direct the air exiting the annual plenum.  Nex Flow Air Jets have several specially designed Coanda angles and can produce the same high level of force and flow with 25% less energy and lower noise levels.

Large annual Air Amplifiers also have efficiency variations among different manufacturers because of internal and external design differences.   A somewhat abused term that often comes up with annular Air Amplifiers is “amplification ratio”. One should be very wary of, frankly, ridiculous claims of high amplification ratios. For example, for annular air amplifiers, the maximum practical ratio you can achieve is about 20 to 1.

This means that if you measure the flow at the exit of an annular Air Amplifier, the flow rate would be 20 times the inlet air.  For several reasons, some producers are claiming as much as 25 times, which is dubious. One reason is that when surrounding air is entrained with the moving compressed air exiting the opening in the Air Amplifier, “still” outside air will slow down the flow velocity at the outlet.

If you entrain, for example, 25 times the compressed air consumed, the velocity would be 20% less than it would be if the figure were only 20 times. That is significant because you need adequate velocity for both blow-off and cooling.  Secondly, the explanations one can read on how this extra air amplification occurs should be challenged as defying physics.

In comparison, Nex Flow has done with such products, the results were a lower air amplification and even lower overall performance because of internal design and extra pressure losses internal to those systems. Anyone can always compare a Nex Flow Air Amplifier to another and see the difference. Nex Flow fixed Air Amplifiers, for example, claim 16 times amplification with a compressed air supply at 80 PSIG (5.5 bar) pressure and at standard atmospheric conditions. 

These figures are averages because air amplification will go up (as much as 20) at lower inlet air pressure and if the atmospheric air is warm.

Air knives are another area where figures need to be considered between manufacturers.  Air knives are linear air amplifiers. There are two styles of compressed air-operated air knives on the market.  The older style uses several Coanda angles where the air exits a gap, normally maintained using a shim to set the gap, and is bent 90 degrees. 

This gives a decent air amplification ratio of about 10:1 right at the exit and 25:1 to 30:1 measured 6 inches away (due to downstream air entrainment) depending on internal design effects.  Some manufacturers have air knives with two gaps and claim as much of a 50:1 amplification ratio (two gaps, so they double the ratio) which makes dubious sense. You don’t double the air out and the ratio – it does not make sense to have it “additive.” 

So again, it is good to challenge claims that may seem to make sense. Another thing to consider, especially with air knives, is real efficiency. Efficiency, as before, is the force measured at a distance per unit of air consumption, for example, force/SCFM. Internal design can make a difference.  Newer style air knives have the airflow exiting straight out of the gap with air entrainment from special angles on each side of the air gap.

This design will provide 25% more force/SCFM than the older style versions, where the air bends 90 degrees. Hence their popularity has largely displaced the older style, but there are still some applications where the old style is useful.  But even among the new style, design differences can affect performance and efficiency.

Nex Flow, for example, with their Silent X-Stream Air Blade air knife has a different internal design than two other significant air knife manufacturers and has about the same force/SCFM as them at a given pressure except for one thing… Nex Flow produces the same SCFM and same force at 60 PSIG, while the other units get equal performance and efficiency at 80 PSIG.  That means a Nex Flow air knife needs less pressure to do the same job as the others.

It was quite humorous when one manufacturer claimed in a blog that our air knives used so much more air at a given pressure, but without mentioning the force produced, a poorly written defense of the fact that they are less efficient. 

If the Nex Flow unit replaced the competitive unit, the air pressure could be reduced by 20 PSIG. As mentioned earlier in this article, that pressure reduction represents a 10% energy saving. So when comparing products, it is very important to look at all the facts. One of the other aspects of the Nex Flow Silent X-stream Air Blade air knife that dramatically illustrates efficiency is how quiet it is, even compared to other designs of its type. 

One other point to mention is the flow profile.  When an air nozzle, air jet, air amplifier, or air knife produces the amplified airflow, the profile will affect the force per square inch or square millimeter.  This is particularly important in air nozzles. You need to decide on the minimum force required and the surface area you need to address.

This is especially important if putting together a row of nozzles for blow-off.  You want the flow profiles to cover the required area without missing any spots or overlapping. A wider profile produces less force per unit area than a more focused air nozzle.

Air amplification is free, but among different designs, it can be more or less free than others.   Besides reducing energy and noise, it is important to remember that air-amplifying products work at a greater distance than just open pipe or tubing. 

The velocity produced by air amplification products is very important when used for cooling. The high velocity combined with the high flow is important, but they are mutually dependent.  The more flow, the less velocity. The less velocity, the more flow. If the velocity is too low, you will not get the same cooling effect. Think of driving a car on a hot day with the window down. 

It’s the same volume of air coming in to cool you, but the velocity from driving fast helps cool you more. But most certainly, air-amplifying products reduce energy use, and noise levels and make factory operations using compressed air more environmentally friendly.

Hollywood Special Effects with Nex Flow® Compressed Air Accessories

Not only have Nex Flow® products been used for Hollywood special effects for US made movies but also for movies made by other jurisdictions and for special effects in museums and in theme parks.

The most popular products used are the air knives and the air amplifiers for creating special effects where wind or heavy air flow needs to be simulated. The advantage of the Nex Flow air knife design is its high efficiency in being able to produce more flow and force at a lower pressure than competitive units (performs the same at 60 PSIG compared to competitors operating at 80 PSIG).  The Nex Flow Fixed Air Amplifiers as well as more efficient than competitive designs by about 10% and are much more rugged for easier handling and use.

One unique application in a Stephen King movie was the use of a standard air knife which operates by having the compressed air exit the air knife, and bending 90 degrees over a series of angles.  When aiming a flame source against the flow, the air bends the flame also 90 degrees. With some computer manipulation this simulated a barrier against a flame (bending it 90 degrees).  

One of my favorite application is from the original X-files series filmed in Canada.  The fixed air amplifiers were used to simulate heavy air flow as one of the characters (Mulder) in the X-files was taken by aliens from an airplane. That was simulated by using several AM125 units (now the part number has been changed to FX125).

Standard air knives (Model 10024 – 24” long units) have been used in the Keanu Reeves remake of The Day The Earth Stood Still.  If you have seen the movie there are several scenes where the grass is rustling from the wind. This effect was created using the air knives.  Because of its even air flow it made a realistic simulation of wind blowing over a large area that was filmed.

Product has been used even off camera.  In one of the James Bond movies (the most recent James Bond with Daniel Craig) there is a scene where there is a sand storm and the cameras that were doing the filming had protected the camera lenses with air knives that acted as a barrier to prevent the sand from hitting the lenses.

We do not always know what the specific application is for the product.  Several 2” Fixed Air Amplifiers were purchased by a special effect company in Brazil but we were not told of the scene.  In 2018 some products were purchased for apparently a major superhero movie but we were advised that we could not disclose the details. Needless to say, I will be viewing all the superhero movies for clues on where the products might be applied! While it might not be as exciting as appearing in a movie, having your product in a movie is kinda cool!

It’s not only movies that use Nex Flow products.  A large number of 4” Air Amplifiers were purchased a few years back by Universal Studios when revamping their special effect “wind from King Kong’s breathing” at their King Kong ride. They replaced product previously supplied by a competitor with the superior and better priced Nex Flow product.

Museums are also trying to have exhibit that are more interactive. One such museum approached Nex Flow to use a small air amplifier or air jet to simulating the effect of bats flying by people in one of their bats tunnel.

The advantage of using the Nex Flow compressed air amplification technology is the portability, ease of use and also the quiet non-disturbing operation of the products.  The compressed air is supplied by a compressor in the film studio or from a rented portable compressor when filming on site.

Ring Vac® air operated conveyors were also used by one special effect company but in this case we were not advised of the special effect. We suspect it may have been used to simulate the firing of a projectile of some sort.

Regardless of the particular special effect, there are many uses for compressed air accessories in the entertainment industry, whether for films, television, theme parks or interactive displays in museums. The application of Nex FlowTM compressed air products for blowing or conveying is limited only to the imagination. The low cost, compact nature, portability, and low noise level of the products make them attractive to use in creating special effects.

To choose the perfect blow off product for your manufacturing environment it is important to consider the application, placement in the factory, energy savings, health and safety, and finally material durability.

Application

One of the primary criteria for deciding which blow off product is right for your manufacturing plant is the application desired.  This section describes the primary application for the following devices: air amplifier, air jet, air blade air knives, and air guns.

An air amplifier is an air mover that is virtually maintenance free. The primary applications of air amplifiers include cooling, venting exhaust, drying, cleaning, distributing heat in molds or ovens, and collecting dust.

Air Jets entrain large volumes of surrounding air. They are similar to air amplifiers but comes in a smaller size yet are more efficient flow amplifiers than nozzles. These jets cover a larger blow off area than a nozzle and are ideal for part ejection. They are primarily used for cooling, part drying, chip removal, and air assist.

Air Blade^TM Air Knives consist of a body with a plenum chamber, cap, and either a machined gap in the body or a shim to maintain an even gap along the length of the air knife. It uses compressed air for industrial blow off and cooling. The laminar sheet of air created by the unit is often used to replace rows of nozzles or jets to reduce energy costs. Air Knife is most commonly used to dry, clean, and cool. Examples of applications include removal of liquid, dust, and excess oils from flat and curved surfaces, conveyor cleaning, blow off before painting surfaces, and scrap removal.

Unlike any of the above units, air guns are not integrated into the factory line but instead are handheld units for blowing off work surfaces and other applications that require a high force or flow application. Safety blow guns are used to blow off metal chips during drilling operations, removing “stuck” material such as tape, gasket material, caulk, adhesive, paint, and labels. With the addition of air, the detached material is blown away during scraping, keeping the area clean.

Location

Although these pressurized air equipment may be ideal for specific applications, they are sometimes interchangeably used based on space availability, desired orientation, and even the factory environment. It is important to keep in mind that these blow off devices must have room for exhaust. Furthermore, if the device is used by a worker, comfortability and ease of maneuver is key.

The shape and size of the unit are important considerations. Air amplifiers and jets are both circular products but jets are smaller in size than amplifiers. Hence the amplifiers can blow off a larger area but with less force than a jet.

Air knives are straight and vary in lengths anywhere  between 3” to 36” and can be used as part of an automated conveyor system. Air guns, on the other hand, are typically used at work stations. Extensions and swivels of various lengths and gun tips (i.e. nozzle and air edger) are available, making the safety gun a very flexible handheld unit.

Energy Savings

Depending on the required application, finding the best fitting blow off product allows the equipment to do the same job at less pressure. Energy savings is accomplished by finding blow off products that have the highest force/air consumption ratio. Reducing compressed air use and noise levels translates into  an efficient high output air with lower energy use.

Here at Nex Flow^TM – we continuously research and design better engineered products for our customers. For instance – our standard air blades have been proven to reduce energy by 30% – 90% as it is designed to produce the most force over the length at the lowest possible input pressure. Taking it a step further – our silent air knives are designed to further reduce energy lost as noise and is 25% more efficient than the standard design.

The best blow off customized product and technical support is obtained by choosing Nex Flow systems.  During installation, our highly trained customer technical support  advises our customers to install equipment that provides the most accurate blowing angles and direction All Nex Flow compressed air blow off products have a five-year warranty against manufacturer’s defects.

Health and Safety

The most important reason to use Nex Flow® blow off equipment is safety.  Air equipment exhaust can be loud. Noise and vibration that are detected by the human ear are classified as sound. “Noise” is the term to describe unwanted sound. Extended exposure to unwanted sound or at high levels can harm workers and can result in profound hearing loss. Hearing loss can also occur as the result of one-time repeated contact to loud sounds or uncomfortable sound pressure over an extended period.

Occupational Safety and Health Administration (OSHA) sets legal limits on noise exposure in the workplace. Guidelines are available that describe permittable duration of exposure for occupational exposure limits (OELs) for various noise levels. These OELs are determined using a weighted average over an 8-hour work day. With unnecessary noise, all workers should be exposed to OSHA’s permissible exposure limit (PEL) of 90 dBA during an 8-hour work day.  Note: The OSHA standard uses a 5-dBA exchange rate.

Nex Flow takes noise levels into consideration very seriously because we understand that reducing noise levels from very loud and damaging compressed air equipment is important.   Noise levels are much lower when using air nozzles and air jets. The added bonus is that the use of air nozzles and air jets, not only lower noise levels but also lowers energy use.

All Nex Flow blow off products provide noise reduction  in factories to ensure the safety of your workers in a factory environment.

Some Air Gun suppliers do not provide energy effective nozzles or are not safe to use. All Nex Flow® air guns are safe to use,  have energy efficient nozzles, and meet OSHA guidelines for safety.

Reducing unwanted noise can be achieved through using noise-canceling headphones, mufflers on any exhausting air, or by adding low-cost air amplifying nozzles on blow off devices. To further enhance safety in the manufacturing environment, Nex Flow^® monitoring devices can detect sources of noise previously missed or unidentified. Use the Nex Flow Digital Sound Level Meter to accurately monitor noise levels and ensure that high levels of sounds do not exceed OSHA limited standard 29 CFR – 1910.95 (a) which limits an 8-hour exposure of constant noise to 90 dBA.  The maximum hold setting will provide the highest noise level and will update continuously if a higher noise level comes into play.   If you need to keep a record of sound measurements, a complete data logging system is available.

All of Nex Flow blow off equipment provides noise reduction, meets OSHA safety standards, and are safe to use in any factory environment.

Material Durability

Compressed air operated equipment is generally simple to use, compact, rugged, and portable.

To keep our products durable – we do not use plastic shims to save costs like other manufacturers. Nex Flow^TM only uses stainless steel shims to guarantee longer life with still very competitive prices.

It is also important to choose the correct material used to construct the accessories. In a high temperature and corrosive environment, 303/304 Stainless Steel is recommended. The 316L Stainless Steel is recommended for very corrosive or high temperature applications and when the application is food or pharmaceutical grade. Anodized Aluminum is usually suitable for most other application but for oily environment it may be worth choosing the hard-anodized aluminum. Learn more about “Why we do what we do with our materials” here (Link to article).

Nex Flow is the best supplier of blow off products.  Our trained customer service and installation technicians can help you identify the criteria that is most important for your blow off application.  Educating your workers, while performing regular inspections will enhance their work environment, prevent leaks, and extend the life of your blow off equipment. When choosing the best blow off solution, understanding the benefits of a well-engineered Air Knife, Air Amplifier, Air Jet, and Air Guns to withstand a harsh factory environment with safety in mind is important.  Remember Nex Flow is happy to help you and your company to meet all your compressed air needs.

LOUDER DOES NOT MEAN MORE POWER

Have you ever heard someone said something along the lines of “well that’s definitely a powerful machine – just listen to how loud it is”. While this may be true some of the time it is not always the case.  When working with compressed air, having a well-designed machines and accessory that is equally powerful at a much lower noise level is always a plus. Here are some things to consider about noise.

Loud Noise Means Less Efficiency

Have you ever tried to concentrate with loud noise? It is much more difficult to think clearly with loud noise. But it’s not just personal efficiency that can be negatively affected, the efficiency of the device making the noise can also be jeopardized. For instance, the noise involved with compressed air blow-off can mean a leakage or an inefficient design. It is still prevalent to use open tubes and jets and drilled pipe for blowing compressed air in production applications to clean, cool and move products. However, the exhaust noise using these methods can exceed 90 dBA depending on the pressure used and the bulk of the noise generated by this method of blowing with compressed air is from the energy lost as it exits the tube or pipe. In other words, the energy is loss as noise and pressure drop because the flow and force from dilled pipes and open tubes are mostly turbulent.

Turbulent Flow can be characterized as having tiny whirlpool regions and it also increases the amount of air resistance which is useful for accelerating heat conduction and thermal mixing. However, it is not useful for blowing applications. Turbulent flow will produce a great deal more noise. For blowing with compressed air, whether for cooling or cleaning or drying, laminar air flow is preferred.

Laminar Flow is when the flow of a fluid (in this case, air) follows a smooth path, or paths which never interfere with one another. One result of laminar flow is that the velocity of the fluid is constant at any point in the fluid movement path.

Just how much can noise be reduced and how much energy saved using blow off products that produce a laminar flow? The answer is – quite dramatic. A laminar flow nozzle can reduce noise levels as much as 10 dBA and reduce energy consumption by 30% – 40%. Likewise, laminar flow air knives which is basically long, flat nozzles are used to replace drilled pipe for higher efficiency. Some designs are extremely quiet and can reduce exhaust air noise to as low as 69 dBA.

High Noise Level is a Hazard

Of the roughly 40 million Americans suffering from hearing loss, 10 million can be attributed to noise-induced hearing loss (NIHL). NIHL can be caused by a one-time exposure to loud sound as well as by repeated exposure to sounds at various loudness levels over an extended period of time.

Sound pressure is measured in decibels (dB). The average person can hear sounds down to about 0 dB, the level of rustling leaves. A handful of people with very good hearing can hear sounds down to -15 dB. On the other end of the gauge, a sound that reaches 85 dB or stronger can cause permanent damage to your hearing even if exposed for a very short time. The timespan you listen to a sound affects how much damage it can cause. The quieter the sound, the longer you can listen to it safely. A very quiet sound will not cause damage even if you listen to it for a very long time. However, a sound that reaches 85 dB can cause enough damage to induce permanent hearing loss. Here are some common sounds.

• A typical conversation occurs at 60 dB – not enough to cause damage.
• A bulldozer that is only idling (not actively bulldozing) is loud enough at 85 dB – after only 8 hours it can cause permanent ear damage.
• When listening to music – a stock earphones at maximum volume can generate sounds reaching a level of over 100 dBA. Loud enough to begin causing permanent damage after just 15 minutes a day!
• A clap of thunder from a nearby storm (120 dB) or a gunshot (140-190 dB, depending on weapon), can both cause immediate damage.

It is estimated that as many as 30 million Americans are exposed to potentially harmful sounds at work. Even outside of work, many people participate in recreational activities that exposes them to harmful noise (i.e. musical concerts, use of power tools, etc.).

Designing the Future of Air Blow Off Technology

Nex Flow^® Air Products Corp. continually perform and fund research to constantly improve the efficiency and safety of compressed air accessories. With this approach, we are able to offer noise reduction for compressed air technologies that are equally or more efficient than competitive units.

Air Nozzles
Our Air Nozzles are engineered to reduce noise by 10 dBA over open pipe, tube or jets and maximize laminar flow to increase force/compressed air consumed.

One of the oldest styles of air saving, noise reducing air nozzles are of a cone shaped design. But if you put every single design next to one another both energy saving and noise reduction will vary greatly because many times the aerodynamic design is neglected. Having the nozzle outside appearance as a cone shape in not enough. There are many other (proprietary) factors to consider to truly minimize turbulence and maximize laminar flow. The cone shaped designs are still the optimum style to use for maximizing total volume of flow produced per quantity of compressed air consumed and is especially ideal for cooling applications. Where cost is a factor, this model is ideal.

The Air Mag is another one of our engineered nozzle with patented design. The bullet shaped design trumps the cone shaped design for producing the highest force/quantity of compressed air consumed. The patented design allows the Air Mag to provide the furthest distance for laminar flow compared to competitive units. Other bullet shaped nozzles need to be close to the target as turbulent flow begins to occur after only a short distance from the nozzle. Our unique design helps significantly extend the range of the laminar flow. Due to increased complexity and manufacturing processes, they are more costly than the cone shaped designs. However, they are the best option for when force produced is an important factor.

Air Knives
When replacing drilled pipe with holes, the Nex Flow Silent X-stream Air Blade air knife lives up to its name. At 80 PSIG the unit is runs on just 69 dBA exhaust noise and uses the same air consumption as if running competitive units at 60PSIG. Extremely popular as they often replace competitive units in the field because of the design and quality of manufacture.

Other blow off products we offer include air flow amplifiers, air jets, and many more. Our accessories are used not only for blow off and cooling applications but can also be used for conveying, cleaning and to control static electricity.

The next time you hear a loud sound when using compressed air anywhere in the production line, don’t forget to check and see what is making that noise. Loud noise is a health hazard and is often wasted energy. So, if the source of the noise is coming from an open tube, open pipe or a drilled pipe of any sort, chances are, you can reduce this noise very quickly and even reduce energy and get better performance by using low cost products from Nex Flow^®.

Pressure and Volume amplifier differences

Differences and Application: Pressure Amplifier VS Volume Amplifier

Sometimes when promoting our air amplifiers there is confusion as to whether it is an air “flow” amplifier or an air “pressure” amplifier.

Pressure Amplifiers

Air pressure amplifiers are also known as air boosters and air intensifiers and are used for increasing or boosting existing plant air pressures. Each pressure amplifier comprises a spool valve that acts as a 4-way directional control valve. The single acting compressed air boosters displace air once per full cycle.   Regular plant air, normally at a range of 80 psig to 100 psig (5.5 bar to 6 bar) is supplied to this spool valve, which automatically cycles back and forth. The plant air fed into the spool valve is alternately directed, as the spool cycles to a main air drive piston in the air drive cylinder. This makes the piston cycle back and forth in the pressure multiplier.

The unit also has a high pressure section where the air to be pressurized is supplied. The air flows into the booster’s pressure chamber on the suction stroke through inlet check valves. It is then compressed out of the chamber on the discharge stroke through the outlet check valve. The reciprocating movement of the air drive section, connected directly to the high pressure section, creates a positive displacement of air through the inlet and outlet check valve.

Single and double acting high pressure booster models are available on the market. The single acting compressed air boosters displace air once per full cycle. The double acting high pressure air booster will displace air at every stroke, or twice per cycle, providing higher and more constant flows. Depending on the application pressures as high as 5000 psig can be produced.

These pneumatic air pressure amplifiers can sometimes be installed in different positions. All connections to the pressure amplifier must be equal to or greater than the inlet and outlet connection ports to prevent starving of the booster.

Nex Flow Air Products Corp. does NOT supply air pressure amplifiers.  They supply air flow amplifiers.

Flow Amplifiers

Rather than being a system of vessels, valves and cylinders, air flow amplifiers are an assembled series of parts that normally work on the coanda effect, although they can also utilize a venturi effect if less air flow amplification is required. The air flow amplifiers that utilize the coanda effect are both energy savers and noise reducers because they basically convert pressure “drop” and “noise” losses into flow.  These systems are all based on aerodynamic shape to minimize losses and can “amplify” flow as much as 16 times inlet air or more depending on the size of the unit. The larger the unit assembly, the greater the air flow “amplification” or “air movement”.  Air flow amplifiers are sometimes called “air movers” because they can move large volumes of air or gas.  However, while they can move a large volume of air or gas, the vacuum produced is less.  If a larger vacuum is required then the venture effect is used.  In this case the shape and assembly does not use the coanda effect bur relies on a different means to entrain air or gas.  With this system you obtain a much higher vacuum but air flow amplification is limited to 5 or 6 times the input air volume.

Nex Flow manufactures both a coanda and a venturi version for air flow amplification. The coanda unit is available in two versions: the fixed X-stream Air Amplifiers work on the coanda effect and the compressed air exit gaps are controlled using stainless steel shims.  This gap can be changed by adding shims to open the gap for more air flow and therefore can “move” proportionately more volume. An adjustable version is available so you can “set” the gap to control the amount of compressed air used.

The venturi version from Nex Flow is called a Ring Vac. The units are primarily used for conveying materials as vacuum is more important for these applications. This device consists of a plenum “generator” with holes to discharge the compressed air into the direction if flow. This creates a vacuum behind the flow of air to entrain the atmospheric air. Its construction allows it to make the higher vacuum. A special XSPC version is available, which has the ring of air for the compressed air angled toward the direction of flow around the inside wall of the unit. This design is used when the material conveyed could possibly clog the Ring Vac design.

Pressure Amplifier Applications:

In Automotive manufacturing, air pressure amplifiers are used to provide higher air pressures for use with Robotics in such areas as Paint Booths, even for heavy blow off and cleaning as in welding spots, and for charging air cushions on presses on stamping presses in the body plants. They also provide assistance in procedures such as punching, riveting, and trimming with extra pressure. Other manufacturing and testing applications that have benefitted from Air Pressure Amplifiers are the manufacture and assembly of Brake pads, pressure testing of steering hoses, radiators and radiator hoses, air conditioning condensers, cooling and refrigerant tubing and systems. Air Pressure Amplifiers are also used in automotive repair and tire shops where higher air pressures may be required. Other applications within the automotive industry include the manufacture and testing of Airbags.

These pressure boosters are also used in the oil and gas industry for boosting gas pressures for pressure testing of vessels. Centrifugal compressors equipped with dry gas seals use the process gas as a seal gas. During normal operation, the compression of the gas generates heat, pressure and flow to the seal, preventing contamination and condensation. During start up or shut down, however, these conditions are not met and the seal is at risk of contamination specifically from heavy condensate.  Air Pressure Amplifiers are used as dry seal gas boosters to ensure that seals are pressurized with dry gas during start up and shut down.

Other common applications for Air Pressure Amplifiers in general manufacturing are as follows:

• Leak detection
• Pressure testing
• Increase pressure to air drying
• Increase pressure to nitrogen generators
• High pressure tire filling
• Increase force from pneumatic valve actuators
• Increase force from pneumatic cylinders
• Increase force from pneumatic presses
• Maintain pressure on inkjet printers for labeling
• Increase holding power of pneumatic chucks
• Increase pressure for products packaging
• Increase force for pigging paint and syrup lines
• Increase pressure on sandblasting equipment
• Increase force of pneumatic springs
• Increase force of pneumatic lift tables
• Increase force of pneumatic shears
• Railroad brake testing
• Unloading railroad cars using pressure
• Shield gas for plasma and laser cutters
• Increase pressure from pneumatic gas boosters
• Increase pressure from pneumatic piston pumps
• Increase pressure from pneumatic diaphragm pumps
• Increase force from ejection pins on plastic molds
• Blow Molding

FEATURED PRODUCTS

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Flow Amplifier Application:

Air Flow Amplifiers or Air Movers like the fixed and Adjustable Air Amplifiers are much simpler devices with lower costs. For Coanda type units, applications include:

• Venting welding smoke
• Conveying light materials
• Trim Removal in paper, film and foil processes if material is light and/or distances are short
• Drying of machine parts
• Cooling of Parts
• Cleaning of machined parts
• To Isothermalize or re-distribute heat in molds and ovens
• Ventilate tanks and other confined areas
• Dust collection
• Exhaust tank fumes

In these applications they are superior to using other devices like fans because they are compact, portable and lightweight.  They have no moving parts, no electricity, no maintenance, are easily ducted and simple in design.  Unlike fans they can be instant on and off and you can vary the force and vacuum.

Cooling of parts with Air Flow Amplifiers is especially advantageous over fans because there is no heat generated and the high velocity laminar flow cuts through the boundary layer on a hot part to remove the heat.  They can cool 10% faster that a fan to be able to increase throughput and with a much smaller footprint, with no maintenance. Cooling castings is a major application for air flow amplifiers using the coanda effect.

Venturi units like the Nex Flow Ring Vacs and XSPC units are used where vacuum is more important than the volume amplified.

• Hopper loading of plastic resin, caps, small parts
• Conveying of material
• Trim removal and waste in paper, film and foil for a wide range of weight and distances
• Transferring parts
• Chip Removal
• Filling Operations
• Tensioning of fiber

The units are compact, with no moving parts, simple in design with high throughput because of higher vacuum.

And of course, Air Flow Amplifiers of both types are low in cost, easy to maintain and last for years.

How is Compressed Air Used to Convey Products?

Compressed air systems are used to convey all types of solids, plastics materials, metal pieces, waste, chip, and trim removal in a manufacturing environment. Internal air conveyor describes items that are moved in the same pipe as the air moving the items. This type of conveyor is used in packaging industries. Since the pressure lessens in the pipe with increased distance, internal air conveyors are limited to lengths of about 100 ft. (30 meters). Sometimes these conveyor systems are referred to as pneumatic conveyors.


In general, pneumatic conveyors easily move items at faster speeds than other types of conveyors. They are also ideal for moving scrap where conventional conveyors would become quickly clogged or contaminated with debris. The inside diameter is recommended to be roughly twice the diameter of the part/material being moved to help prevent clogging. Air conveyors are also useful when transporting sharp or abrasive materials. Metal scrap and recycling centers are perfect places to utilize air operate conveyor because long ribbons of razor-sharp metal can easily snag other types of conveying equipment.

Air Conveyor is most commonly used for moving lightweight objects such as empty containers, boxes, and trays at speeds often exceeding 1,000 fpm, but they are not limited to lightweight materials. Different air operated conveyor systems are designed to convey different types of products and perform various specific tasks. Other common applications include hopper loading (resin in the plastic industry, bottle caps in bottling, etc.), transferring parts from one location to another, tensioning fiber, in filling operations and vent gas in some cases. The gaseous elements are conveyed by the vacuum action and sometimes vented to the atmosphere. Air conveyors are also well suited for handling corrosive or high temperature gas because no electricity is involved, and they can be supplied in appropriate materials. This means that the unit can be customized to meet safety standards and are virtually maintenance free.

How it works?

The Ring Vac and XSPC are air operated conveyor units offered by Nex Flow which uses the Venturi effect. The effect is a version of the Bernoulli’s principle which essentially allows it to increase the speed of the flow to maximize conveying efficiency. Refer to this article to learn more about the Venturi Effect.

The air operated conveyor uses a series of holes to blow compressed air in one direction creating a vacuum to draw in and move the gas. The number of holes in the system is dependent on the size of the unit, which pulls the air behind the unit creating a vacuum, drawing in any gasses and then pushes them away. It is an ideal solution for moving gas through longer distances aided by the extra vacuum.

Other than being used to convey products and goods, air conveyors are sometimes used for venting. Typically an air amplifiers is used for venting purposes, but the pneumatic conveyor do offer some benefits especially if the gas is contaminated or that the vented materials could potentially deposit materials on the Coandă angles of the amplifier. Over time, these deposits could stop the amplifier from venting. For air operated conveyors, the compressed air enters through a different vent, so there is less opportunity for dirt deposits if the gas is contaminated. The air operated conveyor produces a higher vacuum but does not move as much air volume as an air amplifier. The Venturi system is a simple unit to manufacture and is lower in cost. It requires less air pressure to operate and is available in aluminum, stainless steel (standard), with special units made in Teflon, and other plastics and metals.

Unlike an air flow amplifier, the Ring Vac Venturi system moves less volume but creates a higher vacuum. Therefore, this system is ideal for venting gas because it is manufactured at a lower cost and it operates at a lower air pressure thereby saving energy. Do note that, the length of the distances transported vertically and horizontally depend heavily on the types of material being conveyed.

Advantages for air operated transporter systems

Significant advantages of using of these systems are their compact size, instant response time, and portability. They are also clean, quick and efficient machines that are designed to transport or vent a wide variety of lightweight products, raw materials, or fumes from one place to another. Air conveyors typically have minimal moving parts and no pockets to collect debris and water, which makes them safe and easy to clean and maintain. Their flow rate is easily controlled with a pressure regulator.

Overall, the air operated conveyor systems are made so they are easy to use, lightweight, maintenance free and does not use electricity. The systems are ideal for both continuous and intermittent use. They are designed to use compressed air efficiently across the entire length and over long distances.

There are several advantages of using Nex Flow air operated conveyor systems (either the Ric Vac or the XSPC conveyors).

The Ring Vacs are primarily used for conveying materials for applications where a vacuum force is beneficial. The Ring Vac moves objects over long distances at high speeds and has an on/off switch to enhance safety. It uses compressed air, not electricity, so there is no explosion hazard. The Nex Flow Ring Vacs are made of anodized aluminum. For high temperature and corrosive applications, regular and high temperature stainless steel are available. When moving food and pharmaceutical products, 316L Stainless Steel pneumatic conveyors are available. Clamp and threaded versions are available so you can simply clamp a standard hose to each end of the Ring-Vac® to start moving things with compressed air.

• Anodized aluminum for most applications – clamp on and threaded versions
• Extra Powerful hard anodized aluminum – clamp on and threaded versions
• Stainless Steel – clamp on and threaded versions for corrosive and high temperature environments
• 316L Stainless Steel – clamp on, threaded, and sanitary flanged versions for food, pharmaceutical and high temperature and corrosive environments.

Similarly, XSPC conveyors are compact, easy to use, portable, and ideal especially for intermittent use in material transfer. It uses compressed air to create a powerful moving force. The inside of the XSPC conveyor is straight and smooth to prevent clogging. The flow is controlled by a regulator making it perfect for non-continuous use and like the Ring Vac pneumatic conveyor – you can simply clamp a hose to each end to start enjoying the benefits of this efficient pneumatic transporter.

Plan With Nex Flow CAD Models Today!

Some product manufacturers require you to register your personal data to obtain drawings and technical data. Nex Flow does not – as we believe “information that will help you in choosing your product should be free and accessible”. Nex Flow has faith in its products, quality and performance and strive to be there for you when needed. Hence, we do not interfere with the privacy of our product users just because a drawing is needed. We truly believe that our transparency, service, openness and good value can help to optimize any plant in terms of efficiency, energy use, sound levels and much more.

If you would like to receive a monthly update from us – you can opt in to our mailing list in which you can cancel at any time. We consider all customers to be partners treated with respect and that – means reasonable access to information that is required for you to work easily and privately.

One of the most useful information required by anyone utilizing Nex Flow products is the products’ performance but they also need to know if the products will “fit” into an application location. Machine builders and designers require drawings of product to be able to easily incorporate them into their designs. This is the very reason why we openly provide our drawings and dimensions to designers and users so you can best choose the product that “fits” your application.

Four drawing formats provided are:

The most common products where these drawings are utilized are:

The reason being that these products are typically part of a production line that have to be placed and oriented a certain way to work properly and to be assured that they fit for the application.

Other Nex Flow products also have these drawings available even if they are not necessarily incorporated into an initial product design. For example, Tool Coolers, Adjustable Spot Coolers and Mini Coolers come with magnet attachment so they can be mounted easily onto a machine. Sometimes these products are used intermittently because they are not always needed for a particular application or they are moved around and shared between several machines but the information is still necessary to visualize how they can be mounted.

All Nex Flow products need to be connected to a compressed air supply lines, filters, regulators and other types of in line equipment, most often supplied separately by others (although also available by Nex Flow). Machine builders and designers typically go direct to manufacturers of individual products because that is the way to get the best price as well as the technical data and drawings needed. End users usually have standard or existing suppliers for many of the accessories as well.

Air gun drawings are useful to give an idea of how the guns can fit into a person’s hand. There are many low cost – frankly cheap – air guns on the market but many times they are not very well designed for comfort. If the air guns are used extensively, a drawing will help visualize its use in your operation. Of special importance would be heavy duty air guns used for difficult air blow off applications. They need to be especially ergonometric to maximize comfort for the user.

The dimensions of items used in places where space can be a premium is also especially useful – such as vortex tube operated Panel Coolers which are mounted onto control panels but also used for cooling items such as cameras, and vortex tubes themselves. Panel Coolers are normally mounted on the top of control panels and there has to be enough space on the top of the panel, otherwise a side-mount should be used.

Static control technology is another item where drawings are useful in placement of product.  Static eliminators and their distance to the product is critical for their effectiveness and they also require a power supply near proximity to the static bar.

Having easy and anonymous access to these drawings makes the job of designing and choosing a product easier, more efficient and also helps to protect the work of the people using the information freely offered by Nex Flow.

The Coandă effect is the tendency of a stream of fluid (air or liquid) coming from an opening to follow an adjacent flat or curved surface and to entrain fluid from the surroundings so that a region of lower pressure develops. It can also be described as the tendency of a fluid to adhere to the walls of a convex surface.

Commonly a free jet of fluid entrains and mixes with its surroundings as it flows away from a nozzle. The key to the Coandă effect is that when the jet of air comes close to a curved surface, it remains close to the curvature even if the surface is curved away from the initial direction of the jet of fluid. This effect can be used to change a stream’s direction. In doing so, the rate at which the jet mixes are often significantly increased compared with that of an equivalent free jet.

When the fluid increases in speed, the pressure decreases, and this pressure imbalance results in the flow being pushed against the surface by the atmosphere. This means that even if the surface curves away from the direction of flow, the flow keeps sticking to it because the atmosphere is “applying” pressure so the liquid sticks to the surface. This continues until the flow slows down and mixes with ambient air taking away the pressure difference.

This effect is quite widespread in its applications – from airplanes to windshield washers in automobiles and even in air conditioning unit designs and their placement.

Bernoulli Principle and Coandă effect: Their Contributions to Flight

Daniel Bernoulli (1700-1782) discovered an effect named after himself over 300 years ago called the Bernoulli’s Principle. Air behaves like a liquid and when air moves, the pressure around the air parcel decreases. He discovered that if you can move air along a surface, the pressure on that side of the surface will be less than the pressure on its other side. This principal is used to lift airplane wings on aircraft.

The Bernoulli principle describes how planes fly. Aircraft wings have curved top sides and the bottoms are relatively flat. When moving, air hits the front edge of the wing causing some of the air to move up over the wings and the rest to move below the wing. As the upward moving air must follow the curvature of the wing and travels further than the air moving under the wing to reach the back edge at the same time, the air pressure on the top of the wing is reduced according to Bernoulli’s principle. The resulting higher pressure under the wing, lifts the aircraft. This lifting effect pushes the wing upwards and keeps the aircraft in flight.

Daniel Bernoulli : https://en.wikipedia.org/wiki/Daniel_Bernoulli

Though Bernoulli’s principle is a major source of lift in an aircraft wing, a Romanian aerodynamics pioneer engineer, Henri Coandă (1885-1972), discovered another effect that also helps produce lift. Henri Coandă, built the first jet aircraft in December 16, 1910 with his partner Gianni Caponi (another aviator). The plane, called the Coandă-1910, was a 4-cylinder piston engine used to power a rotary compressor. It was displayed in Paris at the Second International Aeronautical Exhibition and, unlike all other planes at the time, the Coandă-1910 did not have a propeller. The motor-driven turbine of his specially designed aircraft sucked the air through the turbine, while the exhaust exited from the rear. This design drove the plane forward by propulsion. Coandă noticed that the airflow was attracted to nearby surfaces. In 1934, Coandă obtained a patent in France for a “method and apparatus for deviation of a fluid into another fluid.” The effect was described as the “deviation of a plain jet of a fluid that penetrates another fluid in the vicinity of a convex wall.” The first official documents that explicitly mention the Coandă effect were two 1936 patents by Henri Coandă. (Coandă effect, Retrieved from Wikipedia on Dec 12, 2018). Unfortunately, the first flight ended in an accident and he could not raise enough money to continue his research.

“A moving stream of fluid, when in contact with a curved surface, will tend to follow the curvature instead of continuing to move in a straight line.”

Like the Bernoulli effect, the Coandă effect also describes how an airplane’s wing lifts. The difference is the Coandă effect describes the angle of attack, which is the angle between the wing and the direction of the air flow, as shown in the following diagram:

The angle of attack indicates the wing’s tilt with respect to the oncoming air. To lift the wing, Newton’s third law says that there must be an equal force acting in the opposite direction. If we can exert a force on the air so that it is directed down, the air will exert an upward force back on the wing. As the angle of attack increases, so does the lift. If the angle of attack is too great, the air flow will stop following the curve of the wing and a small vacuum is created behind the wing causing vibration and decreases the wing’s efficiency.  The wing’s efficiency is important because it directs the airflow downward and pushes up on the wing to produce lift. If the surface is not too sharply curved, the jet of air can follow the surface. The forces that cause these changes in the direction of flow causes an equal and opposite force on the surface along which the jet/stream flows. These Coandă effect/forces causes lift depending on the orientation of the jet and the surface to which the jet/stream adheres. This effect can be induced in any fluids including water.

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Applications of Coandă effect in Compressed Air Industries

Henri Coandă was the first person to recognize the practical application of the phenomenon in aircraft development. The effect is used to power pneumatic production equipment, air operated lathe chucks, pressure clean parts, and to convey or cool components during production for the following industries:

• Chemicals
• Pharmaceuticals (i.e. ventilators)
• Food & Beverage
• Aeration and Agitation
• Semiconductor & Electronics
• Medical Breathing Air
• Automotive for tires and breaks
• Manufacturing

Compressed air is also used for maintenance, power washers, and other cleaning tools.

In air conditioning, the Coandă effect is exploited to increase the throw of a ceiling mounted diffuser. It cools without the use of chemicals. Because the effect causes air discharged from the diffuser to “stick” to the ceiling, it travels farther before dropping for the same discharge velocity than it would if the diffuser was mounted in free air, without the neighboring ceiling. Lower discharge velocity means lower noise levels and in the case of Variable Air Volume (VAV) air conditioning systems, permits greater turndown ratios. Linear diffusers and slot diffusers that present a greater length of contact with the ceiling exhibit a greater Coandă effect.

Henri Coandă : https://en.wikipedia.org/wiki/Henri_Coand%C4%83

The Coandă effect is used in compressed air flow amplification technology to create energy efficient and noise reducing air amplifiers or movers, jets, and knives used in blow off applications. This effect helps to save energy and meet  Occupational Safety and Health Administration (OSHA) standards in compressed industries.

Air Amplifiers or “Movers”

A compressed air flow amplifier works by entraining air along with compressed air. The amplified air utilizes the Coandă effect to draw in surrounding atmospheric air while consuming only a minimal amount of compressed air. These products can amplify airflow up to 17 times with reduced noise levels. The air follows the profile of a pipe outward to cool or dry a surface. Compressed air mixes with ambient air drawn into the device causing the resulting mixed air to have a higher flow and force than the starting ambient air. Air movers are more effective for cooling because of the high velocity outlet flow when compared to flat nozzles. The force produced for blow off decreases as the amplifier outlet diameter increases.

The increased flow reduces the amount of compressed air required. Allowing the Air Amplifier to be used in applications like venting fumes and smoke, conveying low weight materials, and entraining a high volume of air to cool, blow off, or dry.

Air Jets

Compressed air jets generate a high-volume air flow while minimizing compressed air consumption. The compressed air is distributed through an annular ring and is directed towards the outlet using the Coandă effect. This results in the entrainment of surrounding air and results in a great force and velocity compared to the minimized volume of compressed air needed.

Air Knife

Air knives use the Coandă effect for product cooking, drying, and cleaning. An air knife system can be found in most manufacturing and packaging plants such as:

• Food packaging for drying; cooling; removing spills from packaging materials
• Bottle plants for drying cans and bottles
• Metal forming for cleaning; cooling; galvanizing; roll forming
• Foundries and casting plants for cleaning and cooling

For example:

The coating thickness in hot-dip zinc galvanizing process is often done using the gas wiping through an air knife system that uses the Coandă effect. The thickness of the galvanized zinc is of practical importance in determining the quality of product. Such a gas wiping method causes a technical problem of splashing from the strip edge to have a harmful effect on the performance of the galvanizing process and the product quality. The results obtained from “a study on the air knife flow with Coandă effect” Journal of Mechanical Science and Technology 21(12):2214-2220, December 2007, show that Coandă air knife system (nozzle) effectively reduces the splashing problem, leading to improvement of the whole galvanizing process.

Nex Flow Air Products Corp. specializes in the manufacturing of compressed air products for blow off, cooling and moving to optimize energy use and safety.

Compressed Air Uses in the Automotive Manufacturing Industry

Advanced computer technologies, automated assembly systems, and high-quality compressed air systems have changed the automotive manufacturing industry. Consumers can purchase safer, more fuel-efficient and reliable vehicles today than ever before. Using compressed air during manufacturing can also save energy and money during assembly.

Uses of Compressed Air in Automotive Manufacturing

Over the last 100 years, automotive manufacturing has been enhanced by the introduction of compressed air in the assembly line to increase worker’s safety and the overall efficiency of the manufacturing plant. It is used as a tool in almost every step in the process of car manufacturing from painting, cleaning, engine and vehicle assembly. It is also used in car tires and in garages/body shops.  The typical uses of compressed air in automotive manufacturing include:

• Air operated robots
• Plasma cutting and welding to help speed and reliability
• Air tools are preferred to electronic tools because they are light and easy to use
• Breathing Air filters to increase air quality
• Tire inflation
• Automobile finishing

Cars are now made of more durable and light-weight composite materials including plastics. During assembly, compressed air tools create the auto parts and power the lifting, positioning, and moving, fastening machines. It is used to form critical vehicle components such as stamping door panels and trunks.

Both cleaning and painting processes utilizes compressed air. The bare vehicle is inspected for defects and cleaned before painting.  Any contaminants in the air supply will cause expensive re-work, spoilage, and production loss. Clean, dry, oil and contaminant-free compressed air is used to achieve a perfect mirror finish during painting. The compressed air used must have no water or contaminants while painting the car to ensure an even finish. Garages and body shops also use low pressure oil-free compressed air to operate their spray guns. Compressed air is used to agitate the paint in a bath to prevent clumping and mix the color for consistency. Paint is propelled through guns or robots onto a clean metal car body surface using compressed air. To have a consistent reliable paint spray it is critical to choose the right size and type of compressor. Use a compressed air dryer and coalescing filters to remove any naturally occurring moisture to achieve a high-quality paint finish.  

Compressed air conveying system has eased heaving lifting on the assembly line that used to be done by humans. The compressed air conveyor systems use clean dry air to create a thin film of air between the work table and the floor. Using a conveying system, parts are sent through the production line. The major components, including gas tank, suspension, axles, breaks, and steering systems, are installed in the car. Tools such as air-powered wrenches fasten and screw components in place. These tools also remove nuts and bolts with an air ratchet. Grinding and cutting metal is done using a small air powered saw. Robotic machinery now uses compressed air to lift, transport, and position heavy components that were once placed by hand. Compressed air is used to install quarter panels, side panels, and roofs in place. Now that the heaving lifting is done by these air operated machines, the assembly line is much more efficient and safer for workers.

The consistency and reliability of a compressed air tools is the reason for their use in body shops.  Often air sanders are used to smooth out rough metal pieces. It is recommended to use a pneumatic sander since it weighs less than their electric version and are much more reliable in dusty environments.

Results of Contaminants in Compressed Air During Manufacturing

According to the Compressed Air and Gas Institute (CAGI) and the International Organization for Standardization (ISO), the major contaminants in compressed air are oil, water, microorganisms, and solid particles.  Microorganisms are beyond the scope of this article.

ISO 8573 has nine sections that describes compressed air. Section 1 provides a list of contaminants and purity classes. The other sections address sampling techniques and analytical methods for various contaminants.

The following is a list of negative results when compressed air is not clean during automotive manufacturing various types of contaminants.

Oil can:

• Damage equipment
• Cause costly equipment replacement
• Expensive downtime during manufacturing
• Prevent paint adhesion to surfaces
• Paint to crack, flake, or bead
• Create future corrosion or the final finish on a car

When compressed air draws in atmospheric air, it is compressed about a dozen times the normal atmospheric pressure. Atmospheric air naturally contains moisture. The amount of moisture depends on the location (altitude) and season.  In these conditions, the water/moisture will begin to condense since compressed air cannot hold the same amount as normal air. This condensation increases as the compressed air moves through the system/gun and cools. These effects are more evident during the summer with higher humidity. Water can:

• Cause moisture to get pulled back into the compressed air system
• Cause negative visual and textural effects on the finish: spotting or “fish-eyes”
• Stick to pipe walls
• Collect in receiver when the air velocity reduces
• Squirt out of the nozzle with the compressed air
• Collect in the low point of the pipe – then is released at once
• Block the path of the compressed air

NOTE: the condensed water would also have other contaminants collecting in the low point of pipes resulting in a nasty mixture of oil and moisture.

Solid Particles, such as rust, dry particles, and aerosols, can:

• Clog nozzles
• Affect the surface of the finished product

Recommended Best Practices for using Compressed Air in Automotive Manufacturing

It is recommended to replace older units with oil-free centrifugal air compressors piped to heat off compression dryers. The energy savings may not be significant but the benefits of improved air quality and reduced maintenance and water cooling costs.

Reduce compressed air consumption by repairing purge controls on dryers and reducing overall demand. Repair compressed air leaks. Replace timer drains. Replace air operated diaphragm pumps with electric ones. This will modernize air compressors into oil free centrifugal technology able to use heat-of-compression dryers. This reduces maintenance and water-cooling costs with long-lasting and efficient air compressors.

The following simple things can be done to remove oil from your compressed air system:

• Multi-staged filtration between the compressor and the tool
• Pneumatic systems can be filtered at the compressor or point of use

The following simple things can be done to remove water from your compressed air system:

• Check your compressor daily
• Fit a water trap or spinner just before your downstream equipment
• Use desiccant air dryers range form -40 degrees to -100 degrees of dew point – which is helpful in painting, printing, and instrument applications.
• Use deliquescent air dryer, which removes the least amount of water vapor and is not usually found in critical applications where air needs to be very dry. It uses salt-like tablets to absorb water vapor from compressed air.
• Manually drain receiver tanks to rid the system of moisture in the air compressor system or use a timer-based drains and pneumatic auto drains. Remember it is illegal to pour untreated condensate down the drain. It is recommended to treat the water before disposing of it.
• Use a pneumatic water separator can remove up to 99.99% of water and oil from the air supply.
• Use a refrigerated air dryer.  Chilling air lowers the water between 34 and 40-degree dew-point, which is enough for most applications.

Solid particles can be removed by:

• Dry particulate filtration through direct, inertial, or diffusion movement
• Vapor and aerosol filtration through coalescing or adsorption.

Evaluating the Energy Consumption of Compressed Air

Determining the demand on a compressed air system is important. To calculate the load profile, do the following:

• Interview the plant personnel
• Review historical flow records
• Observe loads on the modicum (little) system
• Count the number of machines requiring compressed air in the plant
• Are there plans for new machines? What are the requirements?

From the above observations determine the current maximum possible peak, current peak, average production flow, and low production flow in cfm.

To determine where your current compressed air system can be enhanced to save money, consider the following:

• Ensure that the current compressors are well maintained, installed, and power efficient units.
• Determine the age of the unit
• Determine their maintenance schedule. Does the equipment need lubrication? Does older equipment need to be replaced?

NOTE: Older units are more difficult and expensive to maintain since the parts are no longer available

Factors to Consider to Size and Install an Air Compressor:

This is a list of items to consider when determining the size of your compressor:

• Air pressure requirements based on manufacturer recommended guidelines. The incorrect pressure results in poor tool and machine performance.
• Air demand (psi and CFM)
• Compressed air storage. A simple guideline is 4 to 5 gallons of air storage per CFM.

Also consider the location of the air compressing equipment. The compressor should be installed on a level surface. Follow the recommended guidelines for spacing:

1. Serviceability and access
2. Air circulation and ambient room temperature
3. Location of Power distribution center
4. Ambient air cleanliness
5. Keeping the area around the air compressor clean
6. Employee health and safety – noise and vibration levels.

Nex Flow recommends several products that can help improve the operations of everything from small body shop projects to the more demanding tasks in the automotive manufacturing site. Here is a look at some of their top-performing products applicable to the automotive manufacturing

• Air amplifiers – compact, low cost air flow movers that are maintenance free. The unit uses the Coandă effect to drain in and amplify air flow up to 17 times results in dramatically reduced noise levels. These devices are used for cooling and venting.
• Air nozzles convert pressure to flow efficiently. All Nex Flow Air Nozzles meet OSHA standard CFR 1910.242(b) for dead end pressure and noise levels are dramatically lower in addition to having lower energy use.
• Ring Vac® air operated conveyors are simple, low cost solution compared to other pneumatic conveying systems. Simply clamp a standard hose size to each end of the Ring-Vac® to create this high energy conveying system. There are no moving parts which lend to maintenance free operation while capacity and flow are controlled with a pressure regulator.

What is Industrial Ventilation?

Industrial ventilation is a mechanical system that brings in fresh outdoor air into the workplace (factory or manufacturing plant) and removes contaminated indoor air.  Ventilation is used in a factory to provide a healthy and safe working environment for employees and to remove or have control over contaminants released in an indoor work environment.  The ventilation could be achieved by opening a window (natural) or using fans/blowers (mechanical means). Common pollutants that are removed using an industrial ventilation system include: flammable vapors, welding fumes, dust, mold, asbestos fibers, oil mists, toxic chemicals, moisture and more.

Installing proper industrial ventilation is crucial for providing a safe and healthy environment for workers. They are critical to monitoring indoor air quality. A well-designed ventilation system will bring the air into the workspace at a specific speed creating the required air pressure to ensure cost savings for heating and cooling.

The purposes of a well designed industrial ventilation system are:

• Provide a continuous supply of fresh outside air
• Maintain temperature and humidity
• Reduce hazards for fire and explosion
• Remove or dilute contaminants in the air

An industrial ventilation system consists of two subsystems: the fresh air supply and an exhaust system.

The fresh air supply system includes an air inlet, air filtering equipment, heating and/or cooling equipment, fans, ductwork and air distribution registers.

The exhaust system has an air intake area and ducts to remove contaminated air from one area to another area, an air cleaning device, discharge stacks and fans.

Limitations of Industrial Ventilation Systems

Some limitations of many if not all industrial ventilation systems:

• They require ongoing maintenance because of contaminant build-up within the system, especially filters.
• Regular and routine testing is needed to identify problems early and implement corrective measures.
• Only qualified persons should make modifications to a ventilation system to make sure the system continues to work effectively.
• Making unauthorized changes to the duct system will pull air into the system from the new location resulting in reduced air flow from other locations. The entire ventilation system airflow will be affected resulting in rapid plugging of the system preventing the system from adequately removing contaminants.

Types of Industrial Ventilation Systems

There are three types of industrial ventilation systems: Dilution, Local Exhaust, and Indoor air quality ventilation

Dilution System

A Dilution system reduces the number of contaminants in the air by mixing the contaminated air with clean, fresh air. To install a dilution system, large exhaust fans are installed in the walls or the roof of a factory. This type of industrial ventilation system is used when:

• Air pollution is low and toxicity level is low to moderate.
• Contaminants are vapours or gases
• Emissions are uniform and widely dispersed
• Recommended for moderate climatic environments
• Heat is removed by flushing to the outside
• Mobile contaminant sources are controlled

Advantages of Dilution:

• Needs less maintenance.
• Lower equipment and installation costs
• Recommended for small amounts of low toxic chemicals
• Effectively controls flammable or combustible gases or vapors
• Used for mobile or dispersed contaminant sources

Disadvantages of Dilution:

• Not recommended for highly toxic chemicals
• Does not completely remove contaminants so it is not recommended for high concentrations of dust, fumes, gases, or vapors
• Large quantities of heated or cooled makeup air is required.
• Not recommended for irregular emissions of contaminants.

What is Make up air?

Make up air is the air used to replace the air that was extracted from the workplace. If not replaced, the workplace could become “starved” of air and result in negative air pressure. The negative air pressure could increase resistance on the ventilation system resulting in less air being moved. To determine the pressure in a workplace:

1. Open a door 3 mm and hold a smoke tube in front of the opening. If the smoke is drawn into the room, the room has negative pressure.  If the smoke is pushed away from the room the room has positive pressure. If the smoke raises straight into the air, then the pressure in the room is the same as the outside pressure.
2. Check the resistance when pushing or pulling a door.
3. If the room has a negative pressure – an easy solution is to install a separate intake fan, located away from the exhaust fans to bring fresh uncontaminated air from the outside. Ideally, the air is clean and warmed in the winter or cooled in the summer; as needed. Check some common questions and optimal placement of intake fan here (What are the main features of dilution ventilation?).

Local Exhaust System

A Local Exhaust system captures contaminants at the source and ejects them outside.  It functions on a principal that air moves from high pressure areas to low pressure areas. This difference in pressure is created by a fan that draws air through the ventilation system.

This system is used in areas of high air contamination concentration where there is a greater risk to of exposure to employees. The ventilation system is used for isolated or contaminant sources. This system requires:

• A hood or other device to capture the air pollutants at the source.
• Ductwork as close to the source of contaminants as possible to move the contaminants away from the inside. The material must be compatible with the airstream
• A quality air filter system to clean the air as it moves.
• A fan that moves the air through the system and blows it outdoors
• A stack through which the contaminants are removed.
• The workers are considered in the design, installation, and maintenance of this system.

NOTE: The fan must be the proper type, wheel, arrangement, and size for the application. The fan may require spark resistant construction or other special options.

This system can handle removing many kinds of pollutants including metal fumes and dust. It uses less energy than dilution systems.  This type of industrial ventilation system is used when:

• Inconsistent emissions over time
• High concentration of hazardous materials
• Point sources of contaminants
• Workers are close to the source of contaminants
• Factory is in a severe climate location
• It is required not to turnover air in the factory

Advantages of a Local Exhaust Ventilation System:

• Requires less makeup air because less quantities of air are exhausted
• Reduced energy heating and cooling costs
• Captures the emission at the source and removes it
• The best type of ventilation for highly toxic airborne contaminants, fumes, gases, vapours, and dust.

Disadvantages of a Local Exhaust Ventilation System:

• High cost to design, install, and maintain
• Requires regular maintenance, inspection, and cleaning

Indoor Air Quality Ventilation

Indoor air quality ventilation, which provides fresh heated or cooled air to buildings as part of the heating, ventilating and air-conditioning system (HVAC). The parts of an HVAC system include:

• Air inlet
• Air filtering equipment
• Heating/cooling equipment
• Fan
• Ducts
• Air distribution registers
  

The exhaust system consists of:

• Air intake area
• Ducts to move air from one area to another
• Air cleaning device
• Fans to bring the outside air in the factory and to bring contaminated indoor air outside
• Stacks

Nex Flow® Venting Solution

1. Fume and Dust extractors
2. Ring Vac®
3. Air Volume amplifiers

Fume and Dust Extraction system is designed for portable use, especially for intermittent (on- off) applications. They are rugged and long lasting.  This option is beneficial because of its low cost with reduced noise. For soldering applications, spot welding operations, a small, portable less expensive unit using a small amount of compressed air is more cost efficient than a heavier electronically operated unit.

The system is Low cost and durable and consists of:

• An adjustable air amplifier
• 2” lock-line hose, which draws in a large volume
• Magnetic base – which secures to a metal working table
• A hose can be clamped onto the outlet of the amplifier to take the fumes and dust into a container or out to another area.

Ring Vac® may be added and used to convey collected material beyond 10 feet (3 meters). The Model 40002FMS Stream Vac® (link to product) is affordable compact air cleaning system to remove dust, fumes, and other air pollution from work places. When connected to 10 feet (3 meters) 2” hose compressed air line, the system will remove up to several hundred cubic feet of air with welding and soldering fumes, particulate from local grinding operations, smoke and particulate using very little compressed air.   

Air Amplifiers also called “Air Movers” – can be used for moving a large volume of air. Air Amplifiers uses a small parcel of compressed air to produce high velocity and volume, low pressure air flow as the output.  They are ideal blowing or cooling and for venting. Air amplifiers are used to convey powders and dust, exhaust tank fumes, and moves air 12 to 20-fold in duct appliances to 60 times in area with no ducts. The amplifiers use a small amount of compressed air to draw in a flow of up to 17 times the air consumed to remove fumes quickly and efficiently for venting applications. The fumes can be ducted away, up to 50 feet (15.24 m), and the amount of suction and flow is easily controlled.  

If a large amount of air borne dust or fumes need to be collected and moved a long distance, the air amplifier enhances the air conveyor ability to convey these materials over long distances. The reason is that air conveyors produces high vacuum but move less volume as compared to air amplifiers that move high volume but creates less vacuum. Nex Flow air conveyor systems are manufactured in anodized aluminum for most applications and in 304 Stainless Steel for high temperature and corrosive environments. 316L Stainless Steel air operated conveyors are available for food and pharmaceutical applications. An XSPC range conveyor is also available for moving materials that could clog. Air Amplifiers are lightweight, compact and portable so any application where that can be an advantage is ideal for their use, especially if the use is intermittent minimizing the real energy cost of compressed air.

The following accessories are available with Nex Flow air amplifiers:

• Hose or pipe to collect or transfer materials, fumes, and dust
• Filters
• Mounting systems including brackets
• Regulators
• PLCFC
• Stainless steel shims for maximum product lifespan
• Pneumatic water separator
• Manual valves
• Replacement parts
• Flanges

NOTE: Pipes reduce the air amplification by 10:1 due to back pressure but still provides more efficient air amplification because venture systems move air or vent gas.

Nex Flow air amplifiers are compressed air operated devices that are often used for local ventilation due to their portability.  They are not electrically run so there is no explosion risk. Compact and rugged, they are built to last. If existing systems are not sufficiently strong enough to move the contaminated air, then Air Amplifiers can boost these systems and overcome the losses. This deficiency may be caused by a pressure drop at ventilation entrances.

Filtration is important for maintaining the effective and optimum operation of all Nex Flow air operated products. All Next Flow products used for conveying. such as air amplifiers, air operated conveyors, etc. require clean compressed air. It is essential to use filters to remove water and oil from the compressed air lines. These filters are installed upstream from the air amplifier or air mover in the industrial ventilation system. Air filters should be sized to handle the maximum air flow expected for conveying the contaminated or clean air they are moving. Nex Flow water and oil removal filters are 5 microns and 0.3 microns respectively.

Best Practices for After Installation

It is important to follow through with your employees and train them on the industrial ventilation system. They should be aware of the following:

• How the exhaust system is designed and the intended use.
• The use of the flow restrictors, diverters, and baffles that can alter air movement.

• Keep all hoods, slots, and duct work openings clear of debris, obstructions and buildup which reduces the amount of air entering the ventilation system
• The ideal location to position the employee and the equipment to maximize the amount of air movement into the exhaust hood.
• Employees should continuously observe the ventilation system for damage and flow restrictions. They should be aware of who to report damages to.  A manometer, used to monitor pressure, is a good method of judging if the system require maintenance.
• An employee should perform regular system maintenance, such as changing filters. This will reduce the amount of resistance in the system and improves the systems efficiency.

What does all this mean?

It is important to properly design your industrial ventilation system to achieve the following:

• Provide continual fresh air supply
• Protect workers from heat stroke or cold temperatures
• Reduce fire or explosion risks
• Reduce exposure to airborne contaminants

Although all ventilation systems consist of the same basic principals, each system is designed specifically to meet the requirements of the work environment including the type of work and the rate of contamination release in the factory.  Some important standards and items to consider when designing an industrial ventilation system are:

• OSHA and EPA regulations
• Proper duct design
• Air sampling
• Types of materials used in the construction of the system
• Hazard reduction
• Administrative controls
• Efficient hood design
• Proper fan selection
• Fire and explosion hazards
• Pollution control equipment selection

Our experts at Nex Flow® can help you choose the industrial ventilation system best suited for your manufacturing site or factory. Please don’t hesitate to contact us for more information about our ventilation solutions from a simple Air Amplifier to our Ring Vac® and Fume and Dust Extractor.

Recommended compressed air standards and related terms

There are several major standards to consider with the use of compressed air – two with regard to air quality, one for compressed air safety and any local standards related to noise.

Since compressed air is used in so many areas where it can come in contact with food or medicines, air quality standard is probably the most important standard related to compressed air use.  ISO 8573, established in 1991 is a multi-part standard for compressed air quality to facilitate compressed air system component selection, design and measurement. Part 1 classifies contaminant type and assigning air quality levels, and Parts 2 through 9, define testing methods to accurately measure a full range of contaminants within the end user’s facility.   The ISO 8573 Air Quality standard does not however address how manufacturers are to test and rate the filters. The ISO 12500 filter standard was developed to address this issue and establishes how manufacturers test and rate compressed air filters by defining critical performance parameters (namely, inlet oil challenge, inlet compressed air temperature and pressure measurement techniques) that will deliver certifiable filter performance information suitable for comparative purposes.

ISO 12500 is a multi-part standard, with ISO 12500-1 encompassing the testing of coalescing filters for oil aerosol removal performance, ISO 12500-2 quantifies vapor removal capacity of adsorption filters, and; ISO 12500-3 outlines requirements to test particulate filters for solid contaminant removal.

Occupational Safety and Health Administration (OSHA) standard 1910.242(b) requires that compressed air used for cleaning purposes must be reduced to less than 30 psig (pounds per square inch gauge, 204 kPa). Compressed air used for cleaning must only be permitted with effective chip guarding and personal protective equipment to protect the operator and other employees from the hazards of the release of compressed air and flying debris. Standard 1917.154, which addresses similar hazards in the maritime industry, explicitly prohibits the use of compressed air for personnel cleaning. While this particular requirement is not specifically applicable in the general industry setting, it is recognized as good practice for all industries.  Standard CFR 1910.242(b) is a major guideline for Nex FlowTM  in the design of their air saving nozzles, to keep dead end pressure under 30 psig.

Noise standards vary around the world. Compressed air, when exhausted from cylinders, air nozzles especially, produce noise – both impact noise and exhaust noise.  Please refer to our article on noise levels for more detail.

Terminology used in compressed air systems can be confusing, so we have defined some for you along with common units and conversions below (the terms do not include terms related specifically to the compressors themselves – just terms downstream).

Absolute Pressure – The measure of pressure compared to the absolute zero pressure of an empty space—e.g., a vacuum.  Expressed in pounds per square inch (PSI) or bar (BAR) or kilopascals (KPa). 1 bar equals 14.7 PSI equals 100 KPa

Actual Capacity – Also known as Free Air Delivered (FAD), this is the amount of gas actually compressed and delivered (at rated speeds and conditions) to a discharge system.  Expressed as cubic feet per minute (CFM) or liters (LPM) per minute where 1 CFM = 28.32 LPM.

Air Consumption – The compressed air consumed from the compressed air system by any machine, air tool or blow off device to operate expressed at a particular input pressure to the device and usually in SCFM or SLPM as defined further below.

Amplification Ratio – A term typically used with blow off devices such as engineered air nozzles, jets, air amplifiers, air knives to express the amount of increase in air flow compared to the compressed air used.  Should be expressed at a particular distance from the blow off device. It is usually and average over various inlet pressures.  

Atmospheric Pressure – The measured surrounding pressure of a particular location and its altitude.  Measured in PSI or BAR or KPa as explained above

Blow Off Force – The force produced by a blow off nozzle, jet, air knife or amplifier on pounds force or grams as a particular pressure at the device inlet, expressed at a particular distance from the device.

Free Air CFM or LPM– Air’s flow rate at a specified point and condition, which is then converted to surrounding conditions.

Actual CFM or LPM – Air’s flow rate at a specified point and condition.

Inlet CFM or LPM – Air that is flowing through the inlet filter or valve of a compressor (under rated conditions).

Standard CFM or LPM – The flow rate of free air that is measured and then converted to a uniform set of reference conditions.  Normally expressed as SCFM or SLPM.

Dew Point – The temperature point at which moisture starts to condense in the air, if the air continues to be cooled at a single pressure.

Filters – Devices to remove particles, moisture, and lubricants from surrounding air.

Gauge Pressure – Normally expressed in pounds per square inch (PSIG), this is the pressure most instruments are used to determine.

Intercooling – Process in which heat is removed from gas or air between the stages of compression.

Leak – An unintentional loss of compressed air to surrounding conditions of a compressor.

Pressure – The measure of force per unit area, conveyed in pounds per square inch (PSI) or bar or KPa as compared previously.

Pressure Dew Point – The temperature that water starts to condense out of air for a given system pressure.

Pressure Drop – A pressure loss in compressed air systems caused by restriction or friction. Expressed as PSI, BAR or KPa.

Rated Capacity – At a specified point, this is the volume rate of flow at rated pressures.

Rated Pressure – The measure of the operating pressure of air compressors.

Standard Air – Used in ISO standards, this refers to air at 14.7 pounds per square inch absolute (PSIA), 68°F (20°C), and dry (0% relative humidity).

FEATURED PRODUCTS

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What are Air Amplifiers, Jets, and Knives?

Air Amplifier

There are two types of Air Amplifiers – Air Pressure Amplifiers and Air Volume Amplifiers.   This article talks about volume amplifiers, which harness the energy from a small parcel of compressed air to produce high velocity and volume, low pressure air flow as the output. It can amplify the volume up to 17 times the air consumed.

The volume amplifier uses an aerodynamic effect called “the Coandă effect”. One example of this effect is seen on the Coandă angles on airplane’s wing that can cause the airplane to lift. In an airflow amplifier, the force is directed outward to cool or dry a surface. Pressure normally lost as noise and is converted into amplified and high velocity laminar flow.  

Compressed air stream flows through an air inlet, clinging to the “Coandă” profile inside. The compressed air is throttled through a small ring nozzle at high velocity and guided towards the outlet. This results in a low-pressure area at the center, inducing a high volume of surrounding air flow to the airstream.  Airflow is further amplified downstream by entraining additional air from the surroundings at the exit. This adds further volume and flow to the primary airstream via a similar method. The combined flow of primary and surrounding air exhausts from the Air Amplifier is a high volume, high velocity flow.

The jets of air in the amplifiers create a high velocity flow across the entire cross-sectional area, which pulls in large amounts surrounding air, resulting in the amplified outlet flow.  

Note: Air Amplification Ratio is the ratio of the air flow in standard cubic feet/minute (SCFM) or standard liters per minute (SLPM) at the exit point divided by compressed air consumption with the same unit. This ratio can vary with inlet pressure and temperature as well as the density of the inlet air, so the figure provided is a weighted average. The ratio may be reduced if any back pressure is put on the amplifier exit or suction end by attaching a hose, pipe or tubing

There is a balanced between amplified air flow and air velocity. Any air amplification ratio higher than 17 will slow the velocity so much that the blow off force becomes ineffective and the cooling effect lost.

NOTE: It is recommended to regulate the compressed air supply so the very least amount of air necessary is used.  Install a solenoid valve on the compressed air supply side to turn the air off when the air amplifier is not in service.

Air Jet

Air Jets are either annular like Air Amplifiers or in a flat design (air edger).  Due to their size and “Coanda profile”, annular Air Jets provide a greater concentrated force using amplified air.  This makes them ideal for applications like part ejection. Nex Flow Flat air jets or Flat Jet Nozzles are a compressed air operated chamber of shorter length than an air knife with a higher force and flow design. The internal chamber and outside shape are designed to minimize pressure drop and convert this into flow and force.

Flat Air Jet Nozzle (Air Edger®) is used when a much stronger forced air is required than an air knife can provide.  The flat jet nozzle can be mounted on manifolds of different lengths (holding 2, 4, or 6 units typically and more). Like an air knife – shims can be added to produce higher force. Due to the chamber design that is quite different from an air knife – a greater range of shims can be added to the flat nozzle allowing it to produce much higher air force than an air knife is able to provide.

The Air Edger® Flat Jet is available with various size “gaps” all set with a flat stainless steel shim. Three standard shim sizes are available – .004” (.10 mm), .008” (.2mm) and .020” (.51 mm). Shims can be “stacked” for a larger gap and greater force up to a maximum gap of .024” (61 mm).

Air Knife

An air knife is positive pressurized air chamber that contains a series of holes or continuous slot through which a predetermined air volume and velocity exits. The air is blasted through the air chamber using an air compressor or industrial blower. The air knife is typically made from either aluminum or stainless steel of various lengths but can be made of other materials as well.

Note:  Electrical currents from anti-static bars can also be injected into the air knife air stream to neutralize the static electricity charge on some surfaces.

Things to consider when choosing an air knife includes:

• Force required
• Material: typically aluminum, stainless steel, and special plastics
• Required Length or distance from the compressed air source to the target.
• Installation Cost
• Noise
• Air Consumption

Applications of Amplifier, Jets and Knives

Air Amplifier

There are many different applications for air amplifiers to completely list – but main applications include blow off, cooling, and ventilation:

• Blow off:
  • Purging tanks
  • Used in ventilation of fumes, smoke, lightweight materials from automobiles, welding, truck repair, plating or holding tank or other confined spaces.
  • Circulate and blow off air
• Cool hot parts: Cooling dies and molds
• Dry wet parts
• Clean machined parts:
  • Vacuum device to clean machined parts and confined places: dust collection, remove metal chips and scrap, collect and move dust (grain operations)
  • Clean a conveyor belt or web
• Convey:
  • Used to convey small parts, pellets, powders, and dust.
  • Exhaust tank fumes; Used to remove fumes quickly and efficiently for venting applications. The fumes can be ducted away, up to 50 feet (15.24 m), and the amount of suction and flow is easily controlled.
  • Moves air 12 to 20-fold in duct applications and up to 60 times in areas with no ducts.
  • Component removal, valve gates, and automated equipment for ejection molding systems
  • Distribute heat in molds/ovens
  • Sort objects by weight
• Used as tools in production lines, wood working, aerospace, construction, dentistry, heath care and hospitals
• Used in assembly, chemical processing, robotic cells, and chemical processing
• Increasing existing plant air pressures
• Used in medical, food, and pharmaceutical installations
• Used in Pneumonic cylinders: Enhances efficiency of pneumonic tools and machinery
• Bottle molding applications
• To enhance the “WOW!” factor of amusement rides in certain thrill rides; such as roller coasters
• Coat a surface with atomized mist of liquid
• Activating adhesives and heating-shrinking: High air amplification puts much more airflow through the heater coils than would be possible with an ordinary fan or blower. The hot airstream can be felt over 10′ (3m) away!

Based on Type, Size, and Material:

1. Available 0.002 and 0.003” shims can be added
2. Gap setting from 0.001” to 0.004” to control the output flow and force required.

Special plastic versions are used to cool materials in an electrical power grid where metals can not be used. Alternative materials can be machined to be used as an air amplifier unit in corrosive environments where stainless steel is not sufficient.

Nex Flow manufactures special Air Amplifiers to your specification including special flanged mounting style or with a PTFE plug to avoid sticky material build up.

Benefits to Using Air Amplifiers: For air amplifiers, the outlet flow remains balanced and minimizes wind shear, sound levels are typically three times lower than other types of air movers. Both the vacuum and discharge end of the Air amplifier can be ducted, making them ideal for drawing fresh air from another location or moving smoke and fumes away. They are ideal for increasing existing plant air volume for blowing or cooling and for venting.

• Compact, lightweight, portable
• No electricity
• No moving parts – no maintenance
• Ends are easily ducted
• Instant on/off
• Longer life in difficult environments than competitive models.
• Lower compressed air consumption than ejectors and venturi.
• Maintenance free with output easily controlled, safe to use.

Air Jet

Flat jet air nozzles are used for a concentrated and targeted application of air and other gases. They are used to provide a powerful stream of high velocity laminar flow and high force for blow off and cooling applications where air knives are not sufficient.

Annular Air Jets entrain large volumes of surrounding air through the Jet (like Air Amplifiers) and are more efficient flow amplifiers than Air Nozzles. They cover a larger blow off target than a Nozzle and are ideal for part ejection. An air nozzle provides a point force, while the Air Jet acts more like a “hand” and covers a larger area in blow off coverage.  This can be an advantage in part ejection where two nozzles are normally required to “direct” the ejected part while only one jet is needed.  This can dramatically reduce energy required as well as have a lower footprint on the machine.

Applications of an air jet:

• Part cleaning
• Chip removal
• Part drying
• Part ejection
• Air assist
• For moving heavier material that requires extra force to move.

Benefits to using an Air Jet: Air consumption and noise levels are minimized with its special design and configuration while providing a strong blow off force.

• Reduced compressed air cost
• 10 dBA average noise reduction
• Conserve compressed air
• Compact
• Improved safety
• Meets OSHA noise level requirements
• Improved production

Air Knife

An air knife is used to create an air curtain to clean, dry, or cool a surface of a product without mechanical contact.  In most cases, the air knives are stationary while the products that are cleaned or cooled are traveling on conveyors. In other manufacturing applications, the air knife moves or rotates over the surface of the stationary product. In rare circumstances, an air knife can be used to cut products. One such example in the food industry is by using an air knife to cut into cake frosting.

The following is a comprehensive list of air knife applications using compressed air:

• An air knife is used to blow off a curved or flat surface of unwanted liquid (such as water), grime, airborne debris, dirt, or dust from surfaces or objects using a high-intensity, uniform sheet of amplified airflow.
• Air knives are a good cooling tool.
• They are also used to control the thickness of liquids
• Used in food, pharmaceutical, packaging, automotive, mining, heavy industries (steel and aluminum), and circuit board manufacturing, and printing
• Used the first step in recycling to separate lighter particles from other components.
• Used in post manufacturing of parts for drying, conveyor component cleaning, and to draw in waste fumes or exhaust.  
• Create an invisible air barrier to separate heated or cooled environments from one another in industrial applications such as continuous metal heat treating ovens, cold process or storage areas in food processing or dust containment for the entrance to clean rooms.
• Removal of excess oils, liquids, and dust from flat and curved surfaces
• Part Drying after wash
• Conveyor cleaning
• Component or Parts Cooling
• Drying or Cleaning of Moving Webs
• Environmental Separation (air barriers)
• Blow off in pre-paint systems
• Bag opening in filling applications
• Scrap Removal in converting operations

Benefits to Using compressed air – air knife: Compressed air operated air knives are more compact in design, easier to control, and far less noisy than blower operated units.  

• Quiet – 69 dBA for most applications
• Uniform airflow across entire length
• Minimal Air Consumption
• High Force/Air Consumption Ratio
• Variable force and flow
• No moving parts – maintenance free
• Easy mounting
• Compact, rugged, easy to install
• Stainless steel screws in all models
• Standard Units 30:1 air amplification
• X-Stream Units 40:1 air amplification
• X-Steam Units can do the same job as competition at lower pressures
• Materials Anodized Aluminum, Hard Anodized Aluminum, 303/304 stainless steel and 316L stainless steel
• Stainless Steel shim
• Special Lengths Available

Blower operated systems are advertised as being more energy efficient but that is not always the case.  In intermittent blowing and lower pressure applications, compressed air knives can be as energy efficient as blower operated systems.  

Compressed air operated air knives have smaller/more compact dimensions, more rugged, quieter, and do not have the costly maintenance compared with blowers, making compressed air operated systems the smart choice especially when space is a premium. A compressed air operated air knife provides significantly more force than a typical blower.

Air knives are ideal for liquid and dust blow off. Air knives provide clean, heated air; low operating noise (even without sound enclosures); and easy installation and operation.

Drawbacks to Using Compressed air – Air knife: Not good for heavier material that needs to be removed. In this case, choose an air jet.

Conclusion

Compressed air operated Air Amplifiers, Jets, and Knives are effective tools for your manufacturing environment.  It is critical to know the requirements of your application to choose the correct product. Experts at Nex Flow are happy to assist you in choosing your compressed air solution for your manufacturing application.

COMPRESSED AIR USED IN THE FOOD INDUSTRY

The food industry is huge worldwide.  In the USA alone, there are approximately 1,300 facilities employing about 112,000 people mainly for canning, freezing, and dehydrating fruits and vegetables. This segment represents approximately 7.5% of the dollar value of shipments of the entire U.S. food industry¹. In many fruit and vegetable processing plants, compressed air systems are used for air cleaning of containers prior to product filling, automated product sorting, and product packaging systems². (1,2 Eric Masanet and Ernst Worrell, Lawrence Berkeley National Laboratory, “The Energy Star for Industry Program”, Compressed Air Best Practices Magazine®, October 2006, page 14-15)

There are tens of thousands of facilities in other segments of the food industry using compressed air. Some, like bakeries, use this technology for blow-off applications. Other segments use them to clean containers before filling. Additionally, compressed air is also used to sort, cut, shape and convey food products.  

Another applications are in form, fill and seal operations for cartons. Because these machines must be cleaned thoroughly and regularly to maintain sanitary standards, through washed-down pneumatic systems are preferred since hydraulic systems can have oil leak issues.  Pneumatic also has much less downtime and maintenance needs than hydraulic systems.

Compressed air is very important in the food industry, both for food processing and in the packaging operations.  The air must be contaminant free to ensure food quality and protection. There are standards in all developed countries to have a maximum micron content in filtration and also for dew point control. Dew points of the air at line pressure must be under minus 15 degrees oF (-26 degrees oC) to inhibit growth of microorganisms and fungi.

Some filtration companies, therefore, specializes in filters that meet particular standards of filtration necessary for various processes within food production facilities.

It is not only particulate but also oil which can be a concern.  Where necessary, oil- free compressors are used to supply the compressed air.  

CONTACT – NON CONTACT APPLICATIONS

Compressed air must be purified of contaminants before use in the food industry. The contaminants are water vapor and moisture, solid particulates (including spores) and oil aerosols and vapors.   

Moisture can often be trapped in the piping system near the point-of-use in applications where compressed air comes into contact with food products. Microorganisms and fungus can grow inside the piping system and then be blown into food products or containers. Drying the air to a specified pressure dewpoint is the simple way to eliminate moisture in the system.  The dew point specification can vary from +37 oF (+3 oC) or -40 oF (-40 oC). In some facilities, both of these specifications may be used depending upon whether compressed air has any possibility of coming into contact with food products.

Contact application is when the compressed air is used as part of the production and processing including packaging and transportation of food production or if compressed air comes into direct contact with actual food products. If this is the case, the compressed air needs to be purified to a higher standard than for non-contact applications usually to the -40 oF (-40 oC) dew point, with oil free air and very fine filtration to keep out particulate.

One way to accomplish this is with desiccant (adsorption) type compressed air dryers located in the compressor room (centralized air treatment). Each facility can determine if further point-of-use air dryers (de-centralized treatment) are needed. Point-of-use air dryers may be of either desiccant (adsorption) or membrane-type technology.

Another way to purify the compressed air is by using coalescing filters will remove solid particulates and total oil (aerosol + vapor). Activated carbon filters are usually required as well to remove oil vapors. As with the air dryers, de-centralized filtration may be needed in addition to the centralized filtration system.

Food plants are ideal applications for the use of engineered nozzles and air knives. These are used to blow off on a product and in packaging applications.  These accessories conserve compressed air consumption by utilizing the Coanda effect to entrain surrounding atmospheric air along with the compressed air and create a high velocity, high flow, and a high energy stream of air.


Some applications includes:
– Blow off water after washing a product prior to packaging
– Blow off excess sugar from muffins prior to oven to avoid burnt product
– Cool a product prior to packaging to increase line speed and shorten conveyor length

This air “amplifying” technology not only reduces compressed air energy consumption it also reduces noise levels and have a dead end pressure under 30 PSIG to meet OSHA safety standards on open compressed air exhaust contact.

Non-Contact applications can be categorized into high risk or low risk.  This is when the compressed air is exhausted into the local atmosphere of the food preparation, production, processing, packaging or storage.   

Example of a high risk application is where compressed air is used in a blow-molding process to create a package –then product is put into the package at a later time. Many food processors have their own in-house production lines to create their own packaging.  If there is a delay in the use of the packaging, oil, moisture, and particulates (notably bacteria) could be present if the compressed air is not pure enough. Hence the higher standard for cleanliness. 

In low risk applications higher dew point may be acceptable using a centralized refrigerated type compressed air dryer. Additional point-of-use air dryers (de-centralized) may still be required.  Significant portions (often over 50%) of compressed air in a facility will have absolutely no contact with food products or food-packaging machinery. In this case less costly methods for air treatment are acceptable.  Refrigerated type compressed air dryers normally have significantly lower energy costs than desiccant air dryers. Coalescing filters are required to remove solid particulates and total oil (aerosol + vapor) to the same specification levels as in contact applications and activated carbon filters will be required as well to remove oil vapors. As with the air dryers, each facility can determine if de-centralized filtration is required in addition to centralized filtration.

FEATURED PRODUCTS

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What are the Advantages of an Air Operated Conveyor System?

Air operated conveyors are clean, quick, and efficient machines that are designed to transport or vent a wide variety of lightweight products, raw materials, or fumes from one place to another. They are a family of devices that use air to move products instead of mechanical belts or chains. Internal air conveyor is the term used when the items being moved are in the same pipe or chamber as the air that is moving them. Air transporter systems are popular in material handling and packaging industries. It works by having air flow through louvers to an inner chamber in which items, such as metal scrap, is moved. Internal air conveyors are limited to lengths of about 100 ft. (30 meters) or less due to pressure losses within a pipe.  

Any friction between the product and the system is kept to a minimum. Some system even use ultra-low friction guide materials, such as oil-impregnated Ultra-High-Molecular-Weight (UHMW) or highly polished chrome.  At very high speeds, a week’s worth of dust on a line can create enough friction to reduce line efficiency. Therefore, it is important to keep surfaces clean in these type of systems.

An air conveyor system is used to convey all types of solids, plastic materials, metal pieces, waste, trim removal in a manufacturing environment. It can also be used to vent gas in some cases. The length of the distances transported vertically and horizontally depend heavily on the types of material you are conveying.

Different conveying systems are used according to various needs of different industries

• Bulk conveyors move powders, scrap, coal, bottle caps, and grain. Generally these are not used for delicate objects that could be damaged if not moved in a specific orientation such as bottles, although some heavier bottles are conveyed this way.  An air conveyor system can usually convey the same material as bulk conveyors but with significant less capacity. Low capacity applications where bulk system may apply can be ideal for air operated systems.

• Deck conveyors are used to move cans, caps, and cartons or cases. Deck conveyors work like air hockey tables, except that in addition to the lifting holes, there are directional louvers that direct products. It is not uncommon for deck conveyors to be inclined more than 10 degrees. Specialized systems called “tunnel tracks” are used for cans with decks on top and bottom, which sometime serve as vertical elevators.
  
  This type of carrier requires a guide to keep products from falling over. The guide keeps products from lifting off the conveyor and prevents products from tipping over when starting and stopping. Products without flat tops and bottoms may not work well with this specific system because they are not easily guided. However, there are some products/packages designed so they can be moved without a top cover. Other guide arrangements are also possible. For example, some air deck conveyed products such as plastic ketchup bottles may be guided on the shoulders rather than the top.

• Neck ring conveyors are used to move bottles. Due to the friction of the bottle-neck ring against the neck-ring guide, more air pressure is needed when bottles accumulate back to back to get them moving again.

• Airveyors are devices used for handling dusty materials, which is built on the principle of a pneumatic cleaner. The system used is a suction system, whereby the material (soda ash, salt cake, cement, or powdered lime) is drawn from the car through a flexible hose into a vacuum tank designed to recover a large percentage of the dust floating in the air. An air conveyor can sometimes be used and incorporated into these systems depending on the capacity that needs to be addressed.

• Apron Conveyor is made from linked apron plates with hinges on its underside, thus creating a looped carrying surface where huge and heavy materials are placed.  A mechanism, usually composed of several metal rollers, is placed inside the apron conveyor belt. The apron conveyor is used to deliver many materials across several phases of production. Many industries consider apron conveyors to be a lifeline in their industry, including manufacturing, agricultural, and chemical industries.

• Screw conveyor or auger conveyor is a mechanism within a tube that uses a rotating helical screw blade. It is used to move liquid or granular materials including food waste, wood chips, aggregates, cereal grains, animal feed, boiler ash, meat and bone meal, municipal solid waste, and many others.  The rate of volume transfer is proportional to the rotation rate of the shaft. Although air conveyors are not able to handle the large capacity that screw systems must deal with – rare application can arise.

• Chain Conveyors are used for moving products down an assembly line and/or around a manufacturing or warehousing facility. Chain conveyors are primarily used to transport heavy unit loads, e.g. pallets, grid boxes, and industrial containers. These can be single or double chain strand in configuration.This type of carrier system utilizes a powered continuous chain arrangement, carrying a series of single pendants. The chain arrangement is driven by a motor, and the material suspended on the pendants are conveyed.

• Bucket elevator (also called a grain leg) is a mechanism for hauling flowable bulk materials (most often grain or fertilizer) vertically.
• Vacuum Pump – while not specifically a type of conveying system, electrically operated vacuum pumps are utilized often for venting purposes to move gaseous products of all types, including corrosive gas products.   The gases are conveyed by the vacuum action and sometimes vented to the atmosphere. Air conveyors are better suited when handling corrosive or high temperature gas because they do not use electricity, can be supplied in appropriate materials, are lightweight and compact for easy installation, and virtually maintenance free.

Examples of air conveyors

• Ring Vac: Simply clamp a standard hose size to each end of the Ring-Vac to create high energy conveying system. There are no moving parts for maintenance free operation with capacity and flow controlled using a pressure regulator. Any size longer than  3” (76mm) can be prohibitive for most applications due to high compressed air requirements but 4” and 5” units are available.  The anodized aluminum and high temperature stainless steel Ring-Vac Air Conveyor can move all types of solids in large volumes over great distances with no moving parts.
• XSPC Conveyors: Like the Ring Vac, XSPC conveyors are compact, easy to use, portable, and ideal especially for intermittent use in material transfer.  The difference is that the inside of an XSPC conveyor is straight and smooth so materials, such as textiles, cannot clog.

Air conveyors are most widely used to move lightweight objects such as empty containers, boxes, and trays at speeds often exceeding 1,000 fpm. However, they are not limited to lightweight materials. There are many different types of air operated conveyor systems that are designed to convey different types of products or perform specific tasks.

What are the advantages of using an Air Operated Conveying Systems?

Air operated conveyors easily move items at faster speeds than conventional conveyors.  They are also ideal for moving scrap where conventional conveyors would become quickly clogged or contaminated with debris. The inside diameter can be twice the diameter of the part/material being moved to help prevent clogging.

Air conveyors typically have minimal moving parts and no pockets to collect debris and water, which makes them safe and easy to clean and maintain. The original patent was for coal since it was used to safely vent air in remotely for various explosion-proof settings. Coal comes in a variety of sizes and easily breaks down into smaller, highly flammable particles. Air conveyors are designed to keep coal dust contained and not attract and accumulate dust. This means that they require much less frequent cleanings than belt conveyors moving coal would need. Maintenance is also greatly reduced on air conveyors versus conveyor belts, because the only bearings are on the blowers, which are typically located well outside the area where they would encounter dust and other small particles.  

Air conveyors are also useful when transporting sharp or abrasive materials. Metal scrap and recycling centers are perfect applications for air conveyors because long ribbons of razor sharp metal can easily snag other types of conveying equipment.

Applications of Air Conveying Systems

• Venting Gas
• Combining Air Operated Conveyors with Air Amplifiers
• Hopper loading
• Trim removal
• Filling operations
• Material transfer
• Food ingredients
• Coal
• Grain
• Scrap
• Abrasive or corrosive chemical industry products and fumes

Venting Gas

In a transmission line or a scrubber, the compressed air technology replaces an electrically operated vacuum pump for venting purposes. Electrically operated vacuum pump requires maintenance and a more complicated configuration.

There are two options available depending on the nature of the gas that you want to vent:

• A compressed air flow amplifier, which utilizes the Coandă effect
• An air operated conveyor, Ring Vac and XSPC which uses a Venturi effect.

A compressed air flow amplifier is very quiet and moves large quantities of air. It is an ideal solution when venting clean gas short distances because very little vacuum is required. The compressed air exits a small gap in the amplifier and goes over a series of ” Coandă ” angles converting air pressure to flow. This solution is ideal for venting fumes, dust, and grime. It is complex to manufacture and costs more. This unit requires more air pressure to operate.

An air operated conveyor uses a series of holes to blow the compressed air in one direction creating a vacuum to draw in and move the gas. The Venturi system has several holes, the number depending on the size of the unit, which pulls the air behind the unit creating a vacuum, drawing in any gasses and then pushes them away. It is an ideal solution for moving gas longer distances aided by the extra vacuum. An air operated conveyor is required when the gas is contaminated and there is a possibility that it could deposit material on the Coandă angles of an amplifier, which could stop the venting effect over time.  Since the compressed air enters through a different vent, there is less opportunity for dirt deposits if the gas is contaminated. The air operated conveyor produces a higher vacuum but does not move as much air volume as an air amplifier. The Venturi system is a simple unit to manufacture and costs less. It requires less air pressure to operate. It is available in aluminum, stainless steel (standard), with special units made in Teflon, other plastics and metals.

Therefore, due to the design, cost of manufacture, and requires less air pressure to operate, the Venturi system is often the ideal solution for gas venting applications.

FEATURED PRODUCTS

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Combining Air Operated Conveyors with Air Amplifiers

If a large amount of air borne dust or fumes need to be collected and moved a long distance, the air amplifier enhances the air conveyor ability to convey these materials over long distances. The reason is that air conveyors produces high vacuum but move less volume as compared to air amplifiers that move high volume but creates less vacuum.

How do I select an Air Conveying System?

The factors to consider are:

• Material properties: Consider the characteristics of the material that needs to be moved or removed. What is the particle size and shape, bulk density, moisture content, abrasiveness, friability, cohesiveness, static charge, explosivity, toxicity, melting point, and more?
• Conveying distance: What is the overall distance as well as horizontal or vertical direction of the pipe?
• Available air pressure and velocity
• Transfer capacity: Includes the material properties and the transfer distance.
• Transfer rate: How fast and how often does the material need to be transferred.
• Energy Consumption: Compressed air supply availability

Accessories and Attachments

• Mounting bracket to mount the air operated conveyor
• Clamp to stabilize a hose to each end
• Threaded to thread on a standard pipe for threaded units
• Inlet suction attachment
• Air filters
• Air Regulators
• Air Amplifier

Nex Flow Advantages

Nex Flow air operated conveyor system are lightweight and use no electricity.  The parts are readily installed and easy to use. There is a threaded version as well as clamp on, sanitary flanged units, and other flanged units (optional). They are portable and ideal for continuous and intermittent applications. Our system utilizes compressed air for a powerful, efficient venture action along the length in a compact design for high capacity conveying over long distances. Nex Flow’s products are made from material that is treated to ensure longevity in the product’s life cycle and designed for ease of use and provides simple control of material flow for maintenance free operation.  

Our air conveyor systems are manufactured in anodized aluminum for most applications and in 304 Stainless Steel for high temperature and corrosive environments. 316L Stainless Steel air operated conveyors are available for food and pharmaceutical applications. An XSPC range conveyor is also available for moving materials that could clog.

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

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

Galvanic corrosion and materials

Galvanic corrosion occurs when two dissimilar metals come into contact. It is also necessary for there to be moisture, but it is rare to find an environment without moisture. I still remember visiting a factory and seeing a competitor’s Cabinet Enclosure Cooler (using vortex tube technology) with a big hole on the aluminum cover, obviously caused by some form of corrosion. While the unit was still functioning, this gaping hole made dirt buildup inside the system a definite probability of shortening the life of the unit which, if it used proper materials, or at least anodized the aluminum could last 20 years.

Air blow off products such as air knives, and amplifiers use (usually) aluminum or zinc. Air knives in particular are normally made of aluminum with steel, or stainless steel screws. The further apart the different metals that are matched together are, in terms of relative potentials, the greater the possibility of galvanic corrosion in a wet or humid environment. For example, stainless steel in contact with copper is less likely to be a risk than when it is in contact with aluminum or galvanized (zinc coated) steel. Seawater or salt laden moist air is more of a risk than contact with rain water or say water used for wash down in a factory. Vortex tube operated cabinet enclosure coolers are typically assembled using stainless steel vortex tubes since stainless is the most common material used for vortex tubes due to long life and durability. The surprise is that some manufacturers still, after many years, use aluminum for mufflers, sleeves and casings exposed to a potentially wet factory environment with a stainless steel vortex tube. As long as the environment stays dry, it is not a problem but if the environment is wet, or the enclosure cooler is used in a wash down environment such as in a NEMA 4 (IP56) area, then the risk of galvanic corrosion is much higher.

Anodizing the aluminum is one way to help prevent that from happening as it provides insulation to the galvanic action. But some manufactures of these units have not even done that.

Nex Flow Air Products Corp. uses stainless steel vortex tubes and stainless steel muffling, sleeves, etc. – no aluminum in their cabinet enclosure coolers (Panel Coolers) to avoid galvanic corrosion which can occur if the units are subjected to a humid environment or wash down procedures. Their NEMA 4 (IP 56) units are stainless steel for NEMA 4-4X environments.

What also comes into play is the surface area of each material used. For example, if there is a large area of aluminum and a little stainless steel screw, there will not be much of a problem. Aluminum air knives for example can have stainless steel screws and the galvanic action remains minimal. Nex Flow anodizes their aluminum material to be extra cautious. Most compressed air operated air knife producers however do not anodize. (The near term negative effect of a factory environment on non-anodized aluminum is another topic.)

To keep the aluminum/stainless mix acceptable, the stainless part should be small and the aluminum part large, and of course, keep them dry and away from a humid area. Better still, either anodize the aluminum or just do not mix the materials.

Nex Flow Air Products Corp. manufactures compressed air operated products for blow off, drying, cleaning, cooling and moving along with specialized pneumatic technology to reduce noise, energy use, and to improve the compressed air productivity in a factory environment.

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.

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