Tag: Ring Vac

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.

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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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.

This is a topic that is worked to death from both blower people and compressed air people with bias so firmly ingrained – it is worthwhile to take a step back and look at this topic objectively.

The compressed air market is growing significantly every year at over 6% with 70% of compressed air is used for drying, blow-off and cooling. On the one hand – blower companies would recommend to replace every such application with blowers based on energy costs. On the other hand, compressed air companies tout advantages but focus on often exaggerated maintenance costs applicable to blowers.

As with anything else, the answer is typically somewhere in between and it truly depends on the factors that are important for your particular application.

With reference to a white paper written some years ago –  Compressed Air Versus Blowers – The Real Truth there are eight factors to consider:

1. Availability of particular energy
2. Space and weight
3. Noise level
4. Application particulars
5. Reliability
6. Energy cost
7. System cost
8. Maintenance and operating cost

To explore these factors in detail you can refer to the above article – but here we will add some additional insights for each of the factors.

Energy Availability: It can be just as costly to install an electrical supply if one is not available while compressed air is. The reverse situation is also true. This initial installment cost should be considered.

Space and Weight: One has yet to see a blower operated air blow gun that is not the size of a missile launcher. Try to imagine a series of blower air guns, each with their own blower (which is necessary as you cannot transmit blower air over long distances as you can with compressed air). As such, many blower systems are large, heavy, and harder to handle taking up a lot of the factory’s real estate. This can add up to a significant cost.


Compressed air operated accessories – on the other hand – are smaller in size and easier to work with because it is simply connected to a compressed air supply. Ultimately – ease of use translates to higher productivity. This is why air tools are more popular over electric tools. Having said that, if space is available and cost consideration favors blower operated system. That might be the option to go with – just remember that space and weight can sometimes be overlooked.

Noise levels in factory environments are increasingly an issue. As more research results come to light on noise effects on hearing this become an important factor in personnel safety and health.   Both blowers and compressed air exhaust can be noisy but compressed air exhaust is easily addressed utilizing engineered air nozzles. These designed parts can reduce exhaust noise significantly for compressed air systems. Blowers operate at lower pressure and higher mass flow making them noisier as a result.  Plus the blowers themselves, being in close proximity can create a cacophony requiring silencers at extra cost for safe operation. Blower suppliers try to downplay exhaust noise by stating that regardless of what energy source is used, you cannot reduce impact noise. This is actually true – but more often than not – it is the exhaust noise that adds significant decibel levels to any blow off, cleaning or drying application.

Application particulars is where both sides play with figures. Promoters of blower systems often fall back on the assumption that the alternate compressed air system will operate at a full 80 PSIG (5.5 bar) pressure all the time. However, this is not always the case. Blower systems often claim that it uses ⅓ of the energy used in a compressed air system. But, compressed air system has the ability to be used intermittently. So at full 80 PSIG pressure cycling on and off and actually used only ⅓ of the time – the energy cost suddenly becomes equal.

Compressed air system can use engineered nozzles, air knives, air jets and air amplifiers – all engineered profiles that convert energy normally lost as pressure drop and noise into high velocity flow to recover anywhere from 30% to even 90% energy used for blow off and cooling. Move over – operating pressure can be adjusted in compressed air system so blowing off at 60 PSIG instead of 80 PSIG can save another 10% of energy. Combing on-off use with line pressure adjustments, if is very possible to save more energy using a compressed air system than a blower system.

Energy consumed aside, in many applications pressure provided by blower systems is often not enough.  Higher pressure output from a compressed air system may be required for the job at hand as blower system will take longer to complete the same task and sometimes not able to complete the task at all.

Reliability: You cannot have a central blower system but you can have a central compressed air system with backup.  If a blower goes down, that blower needs to have a backup system brought in – for each location. If reliability is of great importance, then compressed air wins.

Getting back to energy cost, advocates of blower systems focus mainly on the energy cost compared to constant running, always high pressure compressed air options.  With the advance of engineered air nozzles, air blades, air amplifiers and even pulsing systems that reduce compressed air quite dramatically, the claim of being 1/3rd the energy cost of compressed air does not always hold up. The difference can actually be much less in energy use depending on actual compressed air pressure needed and if there is on-off control where the blowing power is not needed all the time.

Overall system cost is also important. Capital cost of blower operated systems are always higher. You need a blower at each location of use, requiring more backup systems as reliability becomes more and more important. The amortization time needs to be factored in.  Blower suppliers offset the capital cost typically against energy savings with little consideration of the cost of downtime and backup system costs and again, take the worst case scenario for energy cost. Compressed air advocates however, can often overstate the maintenance costs involved with blower systems which is also an exaggeration. So both options need careful evaluation for a true accurate overall system cost.

Finally maintenance and operation cost (apart from energy) are important considerations.  Blower companies point out that maintaining air compressors is also a cost but then try to appropriate the entire cost to blow off operations which is not realistic. Air compressors operate cylinders, instrumentation and other devices apart from blow off and cooling operations. If 70% of compressed air is used for blow off and cooling, then at best you can only appropriate 70% of those compressor maintenance costs to those applications.  On the other hand, you would have more blowers to take care of which means generally much more maintenance cost as well as potential additional downtime costs.

In summary, when comparing the alternate technologies it is important to factor out the bias from each alternative to choose the best system. As an illustration, we had a customer (who has since relocated their operation) that was using blower systems to dry radiators that were produced in the factory. Not only was the drying system very noisy, it was also not drying adequately. The client needed a more powerful compressed air system, so they opted for compressed air operated air knives to replace the noisy blower operated air knives. One of the other complaints was the regular breakdown of the blower which may have been just a coincidence, but nevertheless a costly irritant.  The switchover was successful. When the person who made the change left the company a new person came in who was more focused on energy saving and only that so he went back to the blower system. Sometime later the company switched back to a compressed air operated system and with a couple more switches – they finally ended up using the compressed air devices.

Realistically one has to look at the overall costs involved with each system including effect on output and productivity to determine which one is the best option. The above anecdote serves to illustrate that bias very often affect the choices made. It is important to look at all the factors listed earlier to determine what is best for your operation. Blower operated blow off systems are not always the best nor are compressed air blow off systems always the best.  The first place to start is to review what you need to accomplish and work back from there. List what is important in each situation – is it noise? Do you have the maintenance personnel necessary or have access to them as necessary and the cost? How important is reliability? Energy cost is certainly important but so is productivity and production output.

So the next time you go to purchase a compressed air operated hand held air gun, think about why you are using that instead of a blower operated blow gun as an example. It would seem absurd to replace that compressed air device with a blower system due to the large and heavy size it would be plus having a noisy blower next to you (but considering an energy saving air nozzle for that air gun would be something to think about!). Apply this same logic to your factory overall. Where high flow and low pressure is adequate and the system must be constantly running, where noise not a big issue and where there is plenty of space, probably a blower operated system is the best option.  But when the application for blow off is intermittent, where more force is required to maintain productivity and output, reliability is important and space is at a premium, compressed air blow off might be the better option.

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.

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.

Compressed air is a very important tool for food processing and packaging. Food production includes processes like canning, freezing, and dehydration. In this industry – compressed air is used for blow-off applications, cleaning, sorting, cutting, shaping, and conveying food products. It is also used to help form, fill, and seal cartons. The food production industry has approximately 1,300 facilities and employs 112,000 people for processing fruits and vegetables in the United States. The air must be free of contaminants before contact or non-contact with food products.  It is the manufacturer’s responsibility to know the composition of the air used to avoid product contamination. The air quality is the measure of these contaminants in the pressurized air.  If a component of the air has a harmful effect or makes the condition of the product worse – it is considered a compressed air contaminant.  The sources of contaminants in compressed air food processing environments could be physical, chemical, or biological hazards. They include: particles, microorganisms, water, and oil.

Each food processing plant has unique requirements. The goals are to guarantee compliance with standards, levels of food safety, and quality set forth by the FDA and other regulatory entities.  This is critical since food products are ingested by humans and animals.


To apply the appropriate regulatory process to for compressed air and food management systems, recognize the following regulatory organizations:

Regulatory Body	Guideline
Safe Quality Food (SQF) Institute	The New SQF Code, Edition 8: Compressed Air Changes
Food and Drug Administration (FDA)	Food Safety Modernization Act (FSMA)
International Organization for Standardization (ISO)	ISO 8573.1:2010 – Contains purity classes for components/contaminants in pressurized air ISO 8573-3:1999 – Describes methods for measuring water vapor, level of uncertainty, and detection range. ISO 8573-2:2007 – Describes Methods A and B for collecting oil aerosol and liquid samples
British Retail Consortium (BRC)  and British Compressed Air Society (BCAS)	Food and Beverage Grade Compressed Air Best Practice Guideline 102
Global Food Safety Initiative (GFSI)	Benchmark requirements and food safety certification programs for companies to meet high regulatory standards
Food Safety System Certification (FSSC)	Recognized by the GFSI FSSC 22000 certifies and audits food manufacturers using standards from the International Organization for Standardization, ISO 22000 and ISO 22003.
International Featured Standards on Food (IFS)	Focuses on Food safety systems during processing and production. Recognized by the GFSI.
Hazard Analysis Critical Control Point (HACCP)	A code of practice for the food and beverage industry. Includes recommendation for compressed air that comes into indirect as well as direct contact with the product. Goes beyond inspecting finished food product.  It finds, corrects, and prevents hazards throughout the production process. Also recommended by the Codex Alimentarius Commission, the United Nations international standards organization for food safety.

Sources of Contaminants

The possible sources of contaminants in food processing using compressed air are:

• Ambient air can contain anywhere between 5-25 grams of water, 1-5 micrograms of oil, and 10-100 bacterial parts per cubic meter
• Pipes may contain rust, shed metal, or plastic pipes may shed polymer particles
• Charcoal filters and canisters shed particles
• Sealing tape
• Rubber gasket pieces
• Condensed water, liquid, and oil already present in the system form vapor or aerosol.
• Airborne microbes
• Relative Humidity is a source of moisture in the air

NOTE: ISO 8573.1:2010, British Retail Consortium (BRC)  and British Compressed Air Society (BCAS) are specifications that identify potential hazards in the food processing industry.

Impacts of Contaminants

One cubic meter of untreated compressed air contains almost 200 million dirt particles and a lot of water, oil, lead, cadmium and mercury. (Validation of System for Air Quality, https://rastgar-co.com/air-quality/, retrieved November 2, 2018) The impacts of contaminants in a food processing plant are:

• Microbial and bacterial growth on products and equipment
• Corrosive particles landing on sterilized food
• Hazardous consequences to consumer health including the ingestion of hydrocarbons
• Contaminates could accumulate on food products.
• Corrode pipes causing blockages and reduces the life of filters, drains, and machinery in plants.
• Increased energy and money waste.

Understanding Air Quality Factors?

The factors that need to be understood in a food processing environment to improve air quality are:

• Assess the activities and operations that could harm the food product. This is a multistep process:

1. 1. Identify potential hazards
   2. Assess the risk of harm
   3. Assess the controls measures in place for appropriateness
   4. Prioritize controls and hazards for management
   5. Assess the need for extra controls by taking preventative steps to remove or reduce the chance of product harm or harm to the customer
   6. Schedule regular reviews to assess the adequacy of the controls in place

• Determine the extent that the food product is harmed by a potential contaminant
• Determine the likelihood of contamination.
• Understand the impact of air quality on the work zone, workers, and the product or service manufactured.
• Review Direct Product Contact, Indirect Product Contact, USP, and ISO 8573 air standards.
• Understand your requirements for safe food production.
• Engage the production engineers who are most familiar with air quality requirements. They are the resource to determine what needs to be removed from the air and which filter to use for the correct solution. The production engineer would also know the dampness of the air required: moist or dry.

• Determine the amount of moisture required in the air.
• Be aware that pressure reducers and valves can also discharge particles.
• Determine the type of pipes used in the plant

Solutions

The solution depends if the compressed air is in contact with the food product or not.

Contact Application Solutions

Contact application is when the air is used for moving, packaging and transportation of food production. The pressurized air in direct contact with the product 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. Methods to achieve this include:

• Absorption-type compressed air dryers located in the compressor room (centralized air treatment).
• Point-of-use air dryers may be of either desiccant (adsorption) or membrane-type technology.
• Coalescing filters remove solid particulates and total oil (aerosol + vapor).
• Activated carbon filters remove oil vapors.
• De-centralized filtration may be needed in addition to the centralized filtration system.

Engineered nozzles and air knives are used to blow off on a product or packaging while conserving compressed air use by using the Coandă effect to entrain surrounding air along with the compressed air.  These products create high velocity, flow and energy air stream. The applications for these compressed air products include:

• Blow off water after washing a product prior to packaging
• Bottling operations to blow off water, especially under “caps” to avoid subsequent problem in potential corrosion issues
• 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

The Nex Flow Ring Vac compressed air operated conveyor (available in stainless steel and anodized aluminum) are ideal use in food industries. These systems are pneumatic conveying units with no moving parts. They are used to convey solid material at high rates and over long distances, such as:

• Convey bottle caps into a hopper for the bottling line.  Rather than manually loading caps from smaller boxes, larger containers, which are less costly may be used and then the Ring Vac can be utilized to transfer the caps into the hopper.
• Convey solid food items in food blending operations. One specific application was at a company in SE Asia mixing powders for producing a special food spice. Stainless steel Ring Vacs were welding in line and used to transfer various spices from one place into a mixing tank.

Non-Contact Application Solutions

Non-contact application of compressed air in food production includes expelling air into the atmosphere near food preparation, packaging, storing, or conveying. Blow off is used to clean the packaging prior to filling but if there is a time delay after cleaning, there is a greater risk for contamination including oil, moisture, bacteria, and particulates landing on the product or the container. About 50% of compressed air use in food production facilities will have no contact with food products or packaging, so lower cost methods that treat compressed are acceptable. These solutions include:

• Refrigerated compressed air dryers
• Desiccant air dryers
• Coalescing filters are required to remove solid particles and oil (aerosol and vapor) to the same levels required for contact applications
• Activated carbon filters can be used to remove oil vapors
• Centralized or decentralized filtration depending on the food production facility.

General Solutions for Food Production

This is an incomplete list of possible solutions to meet air quality standards in food production environments:

• Guidelines set out by ISO 8573.1:2010, British Retail Consortium (BRC), and British Compressed Air Society (BCAS) specify that air quality should be tested and verified twice per year or per the manufacturer’s recommendations.
• Monitor equipment for particles, moisture, and oil contaminants
• Install and use oil free compressors and use equipment that is most efficient in your plant
• Use only stainless steel or aluminum pipes, which do not corrode
• Reduce relative humidity in the factory
• Use refrigerated air to remove water, then heat the air to room temperature so that the resulting air is low in humidity and bacterial growth

NOTE: When attached to an oiled pipe – the regulations do not state that the air needs to be tested.  

Once the food surface is cleaned, it must be blown with compressed air to ensure no particles are on it.

Refer to ISO 8573 Class 1 or 2 requirements for more information. There is no single solution for all factories when considering the dew point and moisture air management.  Dew points of the air at line pressure must be under minus 15 oF (-26 oC) to inhibit growth of microorganisms and fungi.

NOTE: The dew point is the temperature at which air is so saturated with water vapor that when further cooled – the vapor will condense into water droplets (dew).

When using compressed air to blow out bottles prior to inserting liquids for consumption, the most stringent air standards is not necessary because of the expense or the difficulty to regularly test the air quality. In this situation, it is recommended a point of use filter is installed since 1% of the factory uses very high-quality air for specific applications. The rest of the factory does not need high quality air.  A point-of-use filter is the cheapest and most efficient solution for greater production.

 

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Air Quality Testing Strategies

Assessing the food production system’s controls is a customized activity. Keep in mind that compressed air systems are not static. They are dynamic systems because parts breakdown or malfunction, which requires maintenance.  Air quality testing is critical to sanitation in the food industry. Although standards are not completely in place, the desire to protect consumers is enough to establish regular air testing. Before starting an air quality testing program, determine the following:

• Schedule routine testing for OSHA, FDA, and Current Good Manufacturing Practices (cGMP) verification and compliance at each facility
• Determine the particulate control level required for your environment: size and count.
• Determine the air testing equipment required with sampling media
• Know the type of oil present in the factory so the type of tube required for testing can be determined.

The testing programs should produce valid, repeatable testing results that reinforce the site’s air quality. Sampling strategies must ensure that air provided to all food production areas has consistent quality. Sampling options include:

• Determine the percentage of sampling points to be tested over time: 25%, 50%, or 100%
• Consider taking three samples: close to the compressor, midway through the process, and far away from purification as possible.
• Sample before and after the filter is changed. Data collected after 3 to 4 filter changes is useful for determining trend analysis.Monitoring of air quality can be done by either testing all critical points of application or randomly testing a representative portion. Although testing all critical points is expensive, it is the most accurate. Contamination can occur at any specific location without affecting other areas in the same plant. Results could later show that the one area not tested was contaminated.  Additional testing should be performed after maintenance work is performed on the compressed air system. When maintenance is performed, a sample of air outlets shall be tested to ensure that the quality of the compressed air meets the relevant Purity Classes.

The following is a list of some types of air quality tests:

• Laser particle counter
• Filter collection with microscopy
• Solid Particle content by Mass concentration per ISO 8573-8:2004

When collecting samples, ensure that the collection process does not introduce contaminants. Make sure that the sampling equipment is short, straight and made of stainless steel. Any dead ends or bends in the sampling equipment may cause bacterial growth if not cleaned adequately. Straight sampling equipment is important because it will prevent trapping particles before they are sampled.

After the test results are received, ensure that the results fall within the acceptable thresholds by the standards listed in Table 1.  Ensure that the controls you have in place are maintained by routine air quality testing. If the tests results show contamination in the plant, then either reassess the limits that were set to see if they were inappropriate for the application or add controls to the existing compressed air equipment. Additional controls could include additional filters or a refrigerant dryer where there are none. Although testing could be expensive, it is the best safeguard against damage or harm.

Have you ever considered the manufacturing standards required for sterile products such as medication or medical appliances? Food and pharmaceutical manufacturing facilities require higher quality of air because the products are ingested or placed in humans and animals.  The final product must be free of particles, microorganisms, water, and oil. It is the manufacturers responsibility to ensure the quality of the product that is produced.

The possible contaminants in compressed air in a manufacturing environment include: particles, microorganisms, water, and oil.  The air quality is the measure of these contaminants in the compressed air. An official publication, containing a list of medicinal drugs with their effects and directions for their use (called a pharmacopoeia) – have relatively inaccurate qualities compared to the standards required for pharmaceutical water (Requirements for compressed Air in the Pharmaceutical Industry, retrieved November 2, 2018). Since the requirements are inaccurate, mistakes are made, unnecessary expensive and inefficient designs are implemented; specifically, in the following situations:

• sterile compressed air is not a requirement to manufacture all pharmaceutical products or an entire plant.
• oil free compressed air – standards do not set reasonable mg/m3 limits.

In most cases, compressed air contacts the product. As the pharmaceutical industry has grown, so too has the use of compressed air for breathing air, equipment, and instrument air operation.  The USA accounts for about half of the global pharmaceutical market. Each facility has unique needs so different standards apply. The ultimate goals are guaranteeing compliance with standards, levels of safety, and quality set forth by the FDA and other regulatory entities. Many of the standards in the food industry also apply to the pharmaceutical industry as they both pertains to things human may consume.

To apply the appropriate regulatory process to for compressed air and pharmaceutical management systems, it is worth noting the following regulatory organizations and standards:

 

Regulatory Body/Standard	Guidelines
European Pharmacopoeia for Medical Air standard	“Oil: maximum 0.1mg/m³, determined using an oil detector tube when an oil lubricated compressor is used for the production.” Note: the color change of sulfuric acid absorber is very hard to detect.
BCAS-British Compressed Air Society standard	1. Direct Contact of air with the product: Particles: water: oil = 2:2:1 (as per ISO 8753-1) 2. Indirect Contact of Air with the Product: 2:4:2 (Validation of System for Air Quality, retrieved November 2, 2018)
American Pharmacopoeia for Testing water or oil	Let gas flow over a clean surface and check for oil streaks and/or water droplet formation.
ISO 8573 – Class 1 (2010) and Class 2	It is an international standard that: Categorizes air quality into different classes. Specifies maximum permissible contamination levels for each class. Each class refers to certain Industrial applications. This standard states that no particle larger than 5 µm is permitted in classes 1-5
Indirect and Direct Product Contact standard	An Indirect Impact System is a system that is not expected to have direct impact on quality of product, but typically supports a Direct Impact System.   A Direct Impact system is a system that has a direct impact on product quality. In what I call a “standard pharmaceutical scenario,” we are dealing with a product that is sensitive to temperature, has published storage specifications from stability studies, and the product will be considered adulterated if the manufacturer is unable to prove, through gap-free records, that the product was stored within the published storage specs.   For information, refer to: https://www.vaisala.com/en/blog/2018-09/understanding-impact-indirect-and-direct-systems

Sources of Contaminants

The sources of contaminants in compressed air manufacturing environments are:

• Sources of oil that could exceed the 0.1 mg/m3 requirement include:
  • Leakage spray near the air intake of the compressor
  • Emergency diesel generator being tested
  • Traffic jam on a nearby highway.
  • Oil could be hydrocarbons oxidized to CO2, oil aerosols, or vapor, which could reach the compressed air via the compressor.
• Relative Humidity is a source of moisture in the air
• Micron size particles are naturally in the air
• Corrosion particles flake off due to high flow rate.

Impacts of Contaminants

One cubic meter of untreated compressed air may contain close to 200 million dirt particles and other substances like water, oil, lead, cadmium and mercury. The impacts of contaminants in a pharmaceutical plant are:

• Microbial and bacterial growth on products and equipment
• Hazardous consequences to consumer health:
  • Corrosion Particles landing on a sterile implant or medicine.
  • Exposure to or ingestion of hydrocarbons
• Contaminates could accumulate on manufactured products.
• Corrode pipes causing blockages and reduces the life of filters, drains, and machinery in plants.
• Increased energy and cost of operation.

Understanding Air Quality Factors?

The factors that need to be understood in a pharmaceutical manufacturing environment to improve air quality are:

• Understand the impact of air quality on the work zone, workers, and the product or service manufactured.
• Review Direct Product Contact, Indirect Product Contact, USP, and ISO 8573 air standards
• Understand your requirements. Do you need a clean room in your factory? Clean room air quality is expensive to deliver and maintain.
• Identify the current air quality in the non-clean environment.
• Determine the air testing equipment required with sampling media
• Determine the particulate control level required for your environment: size and count
• Engage the production engineers who are most familiar with air quality requirements. They are the resource to determine what needs to be removed from the air and which filter to use for the correct solution. The production engineer would also know the dampness of the air required: moist or dry.
• Determine the amount of moisture required in the air.
• Know the type of oil present in the factory so the type of tube required for testing can be determined.
• Be aware that compressed air pressure reducers and valves can also discharge particles.
• Determine the type of pipes used in the plant

 

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Solutions

This is an incomplete list of possible solutions to meet air quality standards in pharmaceutical manufacturing environments:

• Develop, and regularly perform site-specific testing programs to produce valid, repeatable testing results that reinforce the site’s air quality.
• Schedule routine testing for OSHA, FDA, and  Current Good Manufacturing Practices (cGMP) verification and compliance at each facility
• Monitor equipment for particles, moisture, and oil contaminants
• Install and use oil free compressors
• Use only stainless steel or aluminum pipes, which do not corrode
• Monitor your intake air: decrease the RH factor and keep it clean
• Use equipment that is most efficient for your factory.

NOTE: When attached to an oiled pipe – the regulations do not state that the air needs to be tested.  

All factory processes do not require the same air quality standards.  When manufacturing equipment that will enter a person’s body (such as knee and hip joints, defibrillators, and pacemakers), a clean room must be designed that uses a spec that ensures a heightened level of particulate control. Once the surface is clean, it must be blown with compressed air to ensure no particles are on it. Refer to ISO 8573 Class 1 or 2 requirements above for more information. If you are creating a clean room in a non-clean environment – the quality of the extremely clean air – is decreased when introduced to the non-clean environment. If the temperature is too cold, it may destroy the manufactured product by hurting or deactivating them. In other products, the moisture in the air could interact with the material resulting in issues. In these situations, extremely dry air is required.  There is no single solution for all factories when considering the dew point and moisture air management.

 

NOTE: The dew point is the temperature that air becomes so saturated with water that if cooled further it will condense to form water.

 

Microbiological limit values are missing for the compressed air both in the pharmacopoeia and in the ISO 8573. The limits based on the clean room classes in which the compressed air is used should be defined, e.g. for class C the max. permissible 100KBE/m³ from Annex 1.

When using compressed air to blow out bottles prior to inserting tablets or to run machinery, the most stringent air standards is not necessary because of the expense or the difficulty to regularly test the air quality. In this situation, it is recommended a point of use filter is installed.  In these cases, 1% of the factory uses very high-quality air for specific applications. The rest of the factory does not need high quality air. A point-of-use filter is the cheapest and most efficient solution for greater production.

Many factories use refrigerated air to remove water, then heat the air to room temperature so that the resulting air is low in humidity and bacterial growth.

Nex Flow works with pharmaceutical manufacturing companies to recommend the right product that complies to operational efficiency and safety.

How does the Venturi System Work?

A Venturi System reduces pressure when a fluid flows through a constricted section (or choke) of a pipe. In 1797, Giovanni Battista Venturi performed experiments on flow in a cone-shaped tube and built the first flowmeter for closed pipes called the “Venturi tube”.  A Venturi vacuum is created by a pump with compressed air running through it, yet the pump has no moving parts. Compressed air runs through the initial chamber, then a smaller portal that opens into another larger chamber, which is like the first one.

 

The static pressure in the first measuring tube (1) is higher than at the second (2), and the fluid speed at “1” is lower than at “2”, because the cross-sectional area at “1” is greater than at “2”.https://en.wikipedia.org/wiki/Venturi_effect

 

Constricting a pipe where fluid flows through results in lower pressure. This principle is counter intuitive to common sense. Why does the pressure decrease? Where does the fluid go if the pathway is constricted? When fluid starts to flow, its velocity around the orifice in the pipe increases significantly because of the restriction in the cross-section. An illustration of this is water flowing through a pipe. Water is a liquid that is not easily compressed. When the water flows through the constricted region of a pipe, the water flows faster.  The same volume of water must pass through the same space quicker. The smaller the constricted region of the pipe is compared to the original radius, the faster the speed of the fluid.

The faster the moving fluid, the lower the pressure (i.e. Bernoulie’s principle) and the higher the velocity, the greater the difference in differential pressure measured. Abrupt restrictions generate severe turbulence in a fluid. Adding a nozzle that are suited for higher flow velocities to fluids with abrasive particles will reduce turbulence and creates less pressure loss.  Turbulence reduction is greater with Venturi nozzles and tubes where the restriction is created by longer, conical constrictions in the pipe wall.

NOTE: The longer the exhaust section of the pipe, the stronger the vacuum effect.

All Venturi systems, including gauges, meters, nozzles, orifice plates, chokes, and pipes can be supplied with different restriction diameter sizes so that the pressure loss and differential pressure generated can be optimized for the process conditions and applications. “In fluid dynamics, an incompressible fluid’s velocity must increase as it passes through a constriction in accord with the principle of mass continuity, while its static pressure must decrease in accord with the principle of conservation of mechanical energy” (Wikipedia, Venturi effect, Retrieved on September 18, 2018).  Therefore, any gain in fluid kinetic energy and velocity as it flows through a restriction is balanced by a drop-in pressure.

Interesting note:  The mass flow rate for a compressible fluid will increase with increased upstream pressure, which will increase the density of the fluid through the constriction (though the velocity will remain constant). This is the principle of operation of a de Laval nozzle. Increasing source temperature will also increase the local sonic velocity, thus allowing for increased mass flow rate but only if the nozzle area is also increased to compensate for the resulting decrease in density.

 

The Venturi system consists of:

• Venturi Vacuum Switch or Nex Flow Ring Vac®
• Hose or pipe
• Minimum 2.5 CFM @ 90 PSI

The Venturi system increases the sucking capacity of any air compressor. To configure a Venturi Vacuum, plug the compressor into one end, move the switch to the vacuum setting, and plug the other end into a vacuum device.

The main component is a Venturi tube. As fluid flows through a length of pipe of changing diameter. To avoid undue aerodynamic drag, a Venturi tube typically has an entry cone of 30 degrees and an exit cone of 5 degrees. (Wikipedia, Retrieved September 18, 2018).

Accessories

• Quick disconnect/connect nozzle fitting
• Pressure or vacuum gauges to monitor how much vacuum is created with the system
• Vacuum pump to collect material and then use the Venturi system to move the material a greater distance

 

Advantages of a Venturi Vacuum System

The best advantages of a Venturi Vacuum System is that it:

• Creates a high vacuum and amplified flow to generate a strong conveying force to move any material with ease.
• Reduces energy costs with less air consumption and uses less pressure.
• Less likely to contaminate air flow because of the straight through design, which prevents clogging.
• Lightweight and portable; Simple configuration, which is easier to manufacture and less expensive to purchase.  Quickly and easily assembled and attaches to existing configuration. Has no valves and requires no filters.
• Configurable: Standard, Threaded (NPT or BSP) or Flanged connection
• Available in a wide choice of materials: Anodized/hard anodized Aluminum, 304/316L stainless steel,  and Teflon. Built to last: materials are treated to ensure longevity in the product’s life cycle
• Exceeds multi-stage pumps by 2 to7 times
• No electrical or explosion hazard

 

Venturi System Applications

Venturi tubes are used in processes where permanent pressure loss is not tolerable and where maximum accuracy is needed in case of highly viscous liquids. It is also used in applications where they replace electrically powered vacuum pumps:

• Gas venting
• Moving metal parts in a machinery rough environment:
  • Hopper loading; Plastic pellets for injection molding
  • Trim Removal
  • Filling operations
  • Material Transfer
  • Sandblasting
• Gas through a transmission line or scrubber: Moves wet and dry material or fluid through a pipe
• Energy Transmission: Transporting solvents and chemicals, for example, oil and gas, steam
• Convert a standard air compressor into a suction machine to secure products with a uniform suction to secure a base to a surface. Using an air compressor as a clamping force also prevents the need for holes on a work surface.
• Measure the speed of a fluid, by measuring pressure changes at different segments of the device:
  • Measure fuel or combustion pressures in jet or rocket engines
  • Measure small and large flows of water and wastewater
• In metrology (science of measurement) for gauges calibrated for differential pressures.
• Water aspirators that produce a partial vacuum using the kinetic energy from the faucet water pressure
• Connect your vacuum bag to make vacu-formed laminates
• Vacuum forming operations for efficient industrial applications
• Atomizers that disperse perfume or spray paint (i.e. from a spray gun).

 

FEATURED PRODUCTS

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What is a Vacuum Pump?

A vacuum pump is a device, which was invented in 1650 by Otto von Guericke. It removes air and gas molecules from a sealed or confined space, which results in a partial vacuum. Sometimes vacuum pumps remove gas from an area, leaving a partial vacuum behind or remove water from one area to another, such as a sump pump does in a basement.  

The performance of a vacuum pump is measured on the speed of the pump or the volume of flow at the inlet in volume per unit of time. The pumping rate fluctuates for each type of pump and the gas/liquid/fluid that it is used on. The number of molecules pumped out of the container per unit of time or throughput is another performance factor.

A vacuum’s suction is caused by a difference in air pressure. A fan driven by an electricity reduces the pressure inside the machine. Atmospheric pressure then pushes the air through the carpet and into the nozzle so that the dust is literally pushed into the bag.

The components of a vacuum pump are:

• Suction: The higher the suction rating, the more powerful the cleaner.  
• Input Power: The power consumption is in watts. The rated input power does not indicate the effectiveness of the cleaner, only the amount of electricity it consumes
• Output Power: The amount of input power is converted into airflow at the end of the cleaning hose. The airflow is often stated in airwatts (watts).

How does a Vacuum Pump Work?

A rotating shaft, in a sealed space, removes air and gas molecules. This action progressively decreases the air density within the enclosure resulting in a vacuum. As the pressure in the enclosure is reduced, it becomes more difficult to remove additional particles. The amount of energy produced by a vacuum pump depends on the volume of gas removed and the produced pressure difference between internal and external atmosphere.

 

The two technologies used by vacuum pumps are gas transfer or capture.

Transfer pumps allocate the thrust from the vacuum side to the exhaust side to accelerate the gas.
They move the gas molecules by kinetic action or positive displacement:

Kinetic transfer pumps direct the gas towards the pump outlet using high speed blades or introduced gas pressure. Kinetic pumps do not typically have sealed containers but can achieve high compression ratios at low pressures.

Positive displacement transfer traps gas and moves it through the pump. They are often designed in multiple stages on a common drive shaft. The isolated volume is compressed to a smaller volume at a higher pressure and expelled to the atmosphere (or to the next pump). It is common for two transfer pumps to be used in series to provide a higher vacuum and flow rate. The expelled gas is above atmospheric pressure when the same number of gas molecules exit the pump as enter it. The compression ratio is the exhaust pressure at the outlet measured in relation to the lowest pressure obtained at the inlet.

Capture pumps capture the gas molecules on surfaces within the vacuum system. This pump works at lower flow rates than transfer pumps but can provide a very strong vacuum. Capture pumps operate using cryogenic condensation, ionic reaction, or chemical reaction and have no moving parts. They can generate an oil-free vacuum.

The mechanical vacuum pumps usually have an electrical motor as a power source, but can alternatively rely on an internal combustion engine, and draw air from a closed volume and release it to the atmosphere. The rotating-vane vacuum pump is the most popular of kind of mechanical pump. Individual rotors are placed around a shaft and spin at high velocities. Air is trapped and moved through the intake port and a vacuum is created behind it.

 

Types of Vacuum Pumps

Pumps can be considered either wet or dry pumps, depending on whether or not the gas is exposed to oil or water during pumping.  Wet pump will use oil or water for lubrication and/or sealing and this fluid can contaminate the swept (pumped) gas. Dry pumps have no fluid. They have tight spaces between the rotating and static parts of the pump, use dry polymer (PTFE) seals, or a diaphragm to separate the pumping mechanism from the swept gas. Dry pumps reduce the risk of system contamination and oil disposal compared to wet pumps.

Note: Vacuum pumps are not easily converted from wet to dry by changing the pump’s style. The chamber and piping can be contaminated if wet. Therefore, all wet pumps must be thoroughly cleaned or replaced, otherwise they will contaminate the gas during operation.

Primary/Booster/Secondary	Name	Type of pump
Primary (Backing) pumps	Oil Sealed Rotary Vane Pump	Wet Positive Displacement
	Liquid Ring Pump
	Diaphragm Pump	Dry Positive Displacement
	Scroll Pump
Booster Pumps	Roots Pump
	Claw Pump
	Screw Pump
Secondary Pump	Turbomolecular Pump	Dry Kinetic Transfer
	Vapor Diffusion Pump	Wet Kinetic Transfer
	Cryopump	Dry Entrapment
	Sputter Ion Pump

Reasons to use a Vacuum Pump:

1. Provide a force
2. Collect dust
3. Remove active and reactive constituents
4. Remove trapped and dissolved gases
5. Decrease thermal transfer
6. Increase the “mean free path” of gas molecules so that the pressure becomes useful.

The mean free path is the distance a molecule travels before colliding with another molecule. A molecule could experience the following types of flow in a vacuum:

1. Viscous flow, turbulent: Tremendous random movement as the molecules try to move into any open space that may lead to a faster exit.
2. Viscous flow, laminar: After a few minutes, the rush of molecules to leave ends and they begin to move to an exit in an orderly fashion.
3. Molecular flow: The mean free path becomes longer inside the diameter of the pipe creating free flow of molecules. The gas molecules will more likely collide with the pipeline (container) walls than with another molecule.  As the pressure drops the conductance also drops until the gas flow changes to molecular flow. Conductance is the measure of the mass of gas flowing at the average pressure per meter of the pipe length.

Advantages of a Vacuum Pump

• Moves large volume of air/low vacuum
• Converts pressure to flow (requires higher pressure to operate)
• Collects dirt, dust, and debris
• Saves energy
• Durable

Vacuum Pump Applications

• Medical processes, which require suction such as therapy or mass spectrometers
• Chemical and pharmaceutical applications
• Scientific analytical instruments that analyzes solid, gas, surface, liquid, and biological materials such as electron microscopy
• Process industries to vent fumes, remove dust and dirt, power equipment, and trash compacting:
  • Sugar mills
  • Pulp & paper
  • Cement
  • Vacuum tubes
  • Electric lamps
  • Semiconductors
  • Glass coating
• Gyroscopes in flight instruments are powered by a vacuum source in case of an electrical failure.
• Treatment plants for sewage systems
• Remove water from one area to another, such as a sump pump does in a basement.

Venturi System VS Vacuum Pump

A Venturi system can be used in many of the same applications as a vacuum pump. The main advantage of Nex Flow’s Venturi system (Ring Vac) is that the units are compact and rugged, simple to configure and requires no maintenance compared to the vacuum pumps. When continuously venting air – choosing a low pressure vacuum pump can save energy costs. However – if intermittent conveying of materials is what you are looking for – a compressed air operated ring vac with an instant on/off switch can save energy cost when using compressed air.

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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[one_third][image src=”https://www.nexflow.com/wp-content/uploads/2017/07/am40-3.png” size=”” width=”” height=”” align=”center” stretch=”0″ border=”0″ margin_top=”” margin_bottom=”” link_image=”” link=”https://www.nexflow.com/products/energy-efficient-blow-off-products/air-amplifiers/standard-fixed-air-amplifiers/” target=”_blank” hover=”” alt=”” caption=”Standard (Fixed) Air Amplifier” greyscale=”” animate=””][button title=”View Product” link=”https://www.nexflow.com/products/energy-efficient-blow-off-products/air-amplifiers/standard-fixed-air-amplifiers/” target=”_blank” align=”center” icon=”” icon_position=”” color=”#27367a” font_color=”” size=”1″ full_width=”” class=”” download=”” rel=”” onclick=””][/one_third]

 

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.

Using Compressed Air Operated Conveyors for Conveying

In utilizing compressed air operated venturi systems such as Nex Flow’s® Ring-Vac®Air Operated Conveyors, you size the unit based on the size of the parts being conveyed.

The general rule is to have the inside diameter of the unit to be double the maximum size or dimension of the parts being conveyed. In this way there is little chance of the parts clogging the unit.

However there are exceptions. One customer for example, had to move a metal rod from one part of the factory to another. This enterprising company utilized the Nex Flow® 2″ Model 30004 Ring-Vac®. The company fed a 1” diameter but 4″ long metal rod into the unit and used the venturi to convey the rod from one end of the factory to another reducing handling time dramatically.

The rod was made to fall onto a gravity feed slot which feeds the rod into the Ring-Vac®. Air is conserved by turning it on only when there is a rod to feed and this is controlled by a sensor. The rod is then literally shot 15 feet up to the ceiling area in a plastic tube connected to the Ring-Vac®. At the ceiling, the feeder tube is then angled about 2 degrees downward where the part is then gravity fed in the tube, across the ceiling, to the other end of the factory which of course, requires no energy.

The part drops out into a bin at the exit of the tube where it is manually picked up for further processing at another machine station. Intermittent applications such as this are ideal for such technology since the unit is low cost, compact, with no maintenance and operates instant on and off only as needed. The use of gravity to feed the part from one end of the factory to the other was brilliant.

Can you think of other applications like this??

Nex Flow Air Products Corp. manufacturers compressed air technology for blow off, drying, cleaning, cooling, and moving and constantly strives to improve their products’ performance and quality. Creative ideas are encouraged and embraced!