EXAIR’s Super Air Knife is THE best solution for compressed air blowoff operations that necessitate a wide sheet of compressed air. We’ve been manufacturing Air Knives for over 37 years, with the Super Air Knife making its first appearance back in 1997. Since then, the Super Air Knife has undergone a few enhancements over the years as we’re constantly trying to not only introduce new products but also improve on the ones we have. We’ve added new materials, longer single piece knives, as well as additional accessories. But, by and large, the basic design has remained the same. As the saying goes: “If it ain’t broke, don’t fix it!”.
The Super Air Knife utilizes a source of compressed air to create a laminar sheet of high velocity air. This supplied compressed air mixes with ambient air that is entrained into the primary airstream. The Super Air Knife entrains ambient air at a rate of 40:1, making it VERY effective in a variety of drying, cleaning, and cooling applications. Available in lengths ranging from 3”-108” and in a variety of different materials of construction, there’s a Super Air Knife available for just about any application. Any time you have product moving along a conveyor that needs to be cleaned, dried, or cooled off, a Super Air Knife is the ideal fit.
Recently I worked with a customer in Mexico that manufactures automotive components. They had a part they needed some help with in their drying process. Before contacting EXAIR, they were placing the parts on racks to let them air dry. They would leave them to sit throughout the shift and dry. The next shift would then come in and gather up the parts, check to make sure they were dried, and then organize them before gearing up to begin production for their shift. In some cases, there was some residual moisture and they would either be dried with a blow gun or with a dry cloth.
This entire process was causing them to lose at least an hour of production per shift. They began looking for something that would allow them to dry the parts immediately at the exit of the washer. They came across EXAIR’s Super Air Knives and implemented of them on the conveyor, immediately at the outlet of the washer to dry both sides of the part. Two knives were placed to dry the top as it had some grooves and features that did not completely dry with just one pass. A third knife was placed on the on the underside as the part is removed from the conveyor to dry the bottom. After implementation of the Super Air Knives, they no longer had to allow the parts to sit and dry on a rack and saved an hour per shift in lost time.
It’s becoming increasingly difficult to staff a complete shift with qualified personnel, so don’t have your operators wasting time in a drying process that can be achieved with something like the Super Air Knife. EXAIR has all models of Super Air Knife available to ship same day from stock and backed by our Unconditional 30 Day Guarantee. If you’d like to talk about how we can help improve a process in your plant, give us a call.
EXAIR Air Knives are amazing. You simply supply them with compressed air, and they are designed to entrain the ambient air around them to generate much more SCFM than is being fed to them at a 30:1 or a 40:1 ratio. They are much quieter, more efficient and a much lower cost (see chart) than any option we know of to blowoff, dry, clean or cool. The Air Knives all produce a nice laminar flow of air that is dependable to consistently handle each application.
There are so many applications, from drying, cooling, cleaning, opening bags, floating webs, and keeping environments separate, to many very unique and creative applications such as; floating tortillas from one belt to another, keeping camera lens covers clean when filming (even on a boat in the ocean), and one application documented on Nat Geo that is, well let’s say extremely unique (find out more here). As there are so many possible applications, there are of course multiple Air Knives to choose from. Our catalogue has 17 pages dedicated just to Air Knives. How do you choose which is best for your application? Let’s take a look and see.
At EXAIR we offer 3 types of Air Knives, Super, Standard, and Full-Flow. All of these are great Knives, and have their own strengths. We also can help If your application requires a special shape, design, or material, we will be happy to work with you to design the best solution for your unique application.
The column on the above left shows you a solid difference of the 3 Air knives. The chart below shows you the most efficient and the quietest Air Knife. You will see that the Super Air knife is our most versatile, by far the most popular purchased Air Knife. Even with a slightly higher purchase price, it doesn’t take long to understand the overall value and long term cost saving makes the Super Air Knife, not only the best choice for nearly all applications, but also the the best value.
All 3 types of Air Knives are stock items, and can typically be shipped the same day. The standard lengths in stock are 3″,6″,9″,12″, 18″ and then every 6″ up to 48″ — The Super Air Knife will go up to 108″ (in stock) with the previous mentioned lengths, plus 54″ and then every 12″ up to 108″ long (yes 9 feet). We can also customize sizes if that is what you need.
As you can see the Super Air Knife is the clear winner of the 3 options and is the most recommended. But there are a few reasons to purchase the Standard and the Full Flow Air Knives. The Standard is generally purchased for the lower price point. The Full-Flow is generally purchased for the small envelope. Here is great way to look at the three options. The Super Air Knife is like a Tesla – it’s arguably the best vehicle on the road today. It is the most efficient with a slightly higher cost than it’s similarly sized counterparts. But when you factor in the cost of gas, the Tesla is actually one of the least expensive option over a lifetime. The Standard Air Knife is more like the family van. It is dependable and it gets the job done, it has a lower sticker price than the Tesla, but each time you fill that gas tank you begin to realize how affordable the Tesla actually was, and you end up having a little regret. Lastly we have the Full-Flow Air Knife that is most comparable to the compact car. Sometimes you need that small car so that you can park in the “compact only” parking places in the parking garages in the city. All of these cars get you from point A to point B, and they all have a purpose and a demand. There is not a bad choice, but there is a best choice, and the best choice is 100% dependent on your needs.
If you have any questions, or would like to discuss in more detail, please reach out to me, or any of our application engineers.
To fully appreciate how impactful a properly functioning air compressor system is to your bottom line, it is foremost important to fully understand how much your compressed air costs. Compressed air is a self generated utility within your facility that is a top 3-4 utility expense for your company. This fact is often overlooked or misunderstood, because the expense is primarily linked to the electric and or gas bill. This can be a costly oversite. You will see an example below where a single common maintenance issue causes a 4psi reduction in performance and resulted in $1265 in additional annual cost to that company. Imagine when/if there are multiple issues…
In order to calculate the compressed air cost, some companies use an educated guess of @$0.25 per 1000 cubic feet of compressed air consumed, and others are more precise. The U.S. department of Energy performed an energy saving study in 2004 and they show a precise way to calculate your compressed air cost. Here is their sample calculation:
“Compressed air is one of the most expensive sources of energy in a plant. The overall efficiency of a typical compressed air system can be as low as 10%-15%. For example, to operate a 1-horsepower (hp) air motor at 100 pounds per square inch gauge (psig), approximately 7-8 hp of electrical power is supplied to the air compressor. To calculate the cost of compressed air in your facility, use the formula shown below:
Cost ($) = (bhp) x (0.746) x (# of operating hours) x ($/kWh) x (% time) x (% full-load bhp) ÷ Motor Efficiency Where: bhp = Motor full-load horsepower (frequently higher than the motor nameplate horsepower—check equipment specification) 0.746 = conversion between hp and kW Percent time = percentage of time running at this operating level Percent full-load bhp = bhp as percentage of full-load bhp at this operating level Motor efficiency = motor efficiency at this operating level Example: A typical manufacturing facility has a 200-hp compressor (which requires 215 bhp) that operates for 6800 hours annually. It is fully loaded 85% of the time (motor efficiency = .95) and unloaded the rest of the time (25% full-load bhp and motor efficiency = .90). The aggregate electric rate is 0.05/kWh. Cost when fully loaded = (215 bhp) x (0.746) x (6800 hrs) x ($0.05/kWh) x (0.85) x (1.0) = $48,792 .95 Cost when unloaded = (215 bhp) x (0.746) x (6800 hrs) x ($0.05/kWh) x (0.15) x (0.25) = $2,272 .90 Annual energy cost = $48,792 + $2,272 = $51,064″
I encourage you to calculate this self generated utility cost for your facility. Also keep in mind that this example is using $0.05/kWh, this example was form 2004, today the average industrial sector cost in the US is $0.0747 (see more here). This annual cost puts so many things into perspective. First and foremost the importance of Maintenance. Even more specific, the preventative maintenance costs become much lower than the impact of even one small oversite. Here is an example from the Department of Energy that discusses a specific and common maintenance issue and it’s annual impact.
“A compressed air system that is served by a 100-horsepower (hp) compressor operating continuously at a cost of $0.08/kWh has annual energy costs of $63,232. With a dirty coalescing filter (not changed at regular intervals), the pressure drop across the filter could increase to as much as 6 psi, vs. 2 psi when clean. The pressure drop of 4 psi accounts for 2% of the system’s annual compressed air energy costs. (or an increase of $1,265 per year)”
The realization of the dollars spent for compressed air certainly pushes the priority of maintenance. If we extrapolate from the above filter example, we can see that a 4 psi pressure drop in that system increased the cost by $1265 per year. We need to then ask ourselves, what other areas could be causing a pressure drop or stressing the motor? And if there is an issue upstream to this issue, will it cause even more issues, or more pressure drops?
There are many tips, tools, websites, YouTube videos and more, out there that address the recommended maintenance of your compressor and system. Many of you already have specific guidelines for your precise system, and set maintenance schedules in place. Below is a sample checklist (not all-inclusive) of maintenance items to watch for with your compressor in case you need a starting point. If left unchecked and or uncorrected, any of these (if an issue) will cost your company money – over time, lots of money.
I would be amiss if I finished this blog without mentioning the perils of pressure leaks. The Compressed Air and Gas Institute stated that a single 1/4″ leak, can cost you between $2500 and $8000 per year (CAGI article). Imagine the impact of several leaks!!!
How do I find leaks? I’m glad you asked. The first step is to walk your lines and check any or all of the following areas for leaks or damage.
A great way to identify leaks is to use our Ultrasonic Leak Detector to listen for leaks. Look for and ask the technicians if there seems to be a change in productivity. Install Pressure Regulators and gauges at each point of use in your facility – monitor and log these pressures often. Once you find an issue, no matter how small, correct it. A small leak adds up $$$ over the hours, weeks, and months.
In addition to leaks, there are many times that air is wasted by being blown on empty space (i.e. the space between items on your conveyor). you, please look at our Electronic Flow Control (EFC) product, this device gives you an out of the box automation solution that can be set up in minutes and save thousands. There are so many clogged and leaking pipes, bad hoses inside many plants, this coupled with using an poor performing Air Gun, or Air Nozzle all have large dollar impacts for your company. EXAIR has products that can help in all of these areas…
In parting, please keep in mind that many Utility companies offer incentives to companies that take an initiative to reduce their energy footprint. In our current time of inflation this is a real way to reduce costs, many times significantly. We are here to help. Please contact us for assistance in dramatically reducing both your utility costs, and your environmental impact.
Thank you for stopping by. Please reach out if you have any questions about this Blog, or any of EXAIR’s amazing products.
A door manufacturer was having some issues in containing the sawdust within their CNC machine. Their operation used two rotary saw blades on a mill arm to cut two grooves in the bottom of a standard 36” (91.4cm) wide door. The grooves were used to hold a Kerf door sweep; a mechanical barrier to keep water, air, and dirt from getting into the house. After the grooving operation, dust was getting on the door and around the conveyor. It was becoming a safety issue as the saw dust would collect on the shop floor. The CNC mill did have a dust collection system, but it needed a little help to keep the material within the collection area.
I recommended the model 110236DX Super Air Knife Deluxe Kit. This model included a 36” (914 mm) Super Air Knife, a filter, a regulator, a shim set, a Universal Mounting System, and an Electronic Flow Control. The filter would capture any contamination from the compressed air line to keep the door surface clean. The regulator and shim set would be used to control the amount of force required to remove the debris and keep the dust from migrating. The Universal Mounting System securely attached to the Super Air Knife to give flexibility in mounting. It uses articulated arms to maneuver the Super Air Knife to the best position for blowing. The Electronic Flow Control, or EFC, is an optimization product that uses a photoelectric eye to turn on and off the compressed air with a timing circuit. When the mill arm passes by the photoelectric eye, the timing circuit would start blowing; and it would turn off after the door has been processed and left the milling area. The EFC is great tool to save on compressed air.
The Super Air Knife was placed underneath the aluminum extrusion guard in front of the door (reference photo above). It was placed to increase contact time and to blow back toward the dust collection system. The force of the air would clear the surface of the door in a non-contact way. As a result, the wood chips and debris stayed inside the CNC machine and removed the slip hazards in other areas of the plant. As an additional note, since the dust collection system was now optimized with the Super Air Knife, the housekeeping within the plant was not needed which saved them time and money.
If you want to have a safer environment for your workers, EXAIR has a line of products that can help. Whether it is for noise, dead-end pressure, or removing slip hazards as above; EXAIR has engineered solutions that can help. You can contact an Application Engineer at EXAIR for assistance.