Cost Savings from Replacing a Drilled Pipe with a Super Air Knife

A few months ago, my counterpart Brian Bergmann wrote a blog providing a detailed explanation of ROI or Return on Investment. Today, I would like to take this information and apply it to a common situation we deal with regularly here at EXAIR – replacing drilled pipe with our Super Air Knife.

Drilled pipe – easy to make but extremely wasteful

Sections of pipe with drilled holes across the length are very common as they are made of relatively inexpensive materials and simple to make.  Where the cost begins to add up is on the operation side as these types of homemade blowoffs waste a ton of compressed air, making them expensive to operate.

For comparison, lets look at a 12″ section of pipe with (23) 1/16″ diameter drilled holes. According to the chart below, each hole will flow 3.8 SCFM @ 80 PSIG for a total of 87.4 SCFM.

With an average cost of $ 0.25 per every 1,000 SCF used (based on $ 0.08/kWh), it would cost $ 1.31 to operate this blowoff for 1 hour. (87.4 SCFM x 60 minutes x $ 0.25 / 1,000)

Super Air Knife – Available from 3″ up to 108″ in aluminum, 303ss and 316ss

Now let’s take a look at replacing the drilled pipe with our 12″ Super Air Knife. A 12″ Super Air Knife will consume 34.8 SCFM (2.9 SCFM per inch) when operated at 80 PSIG. Using the same figure of $ 0.25 per every 1,000 SCF used, it would cost $ 0.52 / hr. to operate this knife. (34.8 SCFM x 60 minutes x $ 0.25 / 1,000)

Now that we know the operating costs, we can make a better comparison between the 2 products.

Drilled pipe operating costs:
$ 1.31 per hour
$ 10.48 per day (8 hours)

12″ Super Air Knife costs:
$ 0.52 per hour
$ 4.16 per day (8 hours)

Cost Savings:
$ 10.48 per day (drilled pipe) –  $ 4.16 per day (Super Air Knife) = $ 6.32 savings per day

A 12″ aluminum Super Air Knife carries a LIST price of $ 297.00. If we take $ 297.00 divided by $ 6.32 (saving per day), we get a ROI of only 47 days.

As you can see, it is quite beneficial to consider ALL of the parameters when looking at a process or application, rather than just the “upfront” details. What seems like a simple and easy fix, can actually be quite  wasteful when it comes to the true cost of ownership.

If you are using similar devices in your plant and would like to see how an EXAIR Intelligent Compressed Air Product can help make the process operate more efficiently, contact an application engineer for assistance.

Justin Nicholl
Application Engineer


Replacing Home Made Blow Offs

Yesterday, I took a call from a customer, who had successful replaced a low cost blow off station with (2) of 6″ Super Air Knife.  The low cost blow off station was made up of two flexible lines with plastic liquid coolant nozzles to dry two surfaces after a roll forming process.  At the beginning of every production run, the nozzles would have to be positioned to hit the surface of the part because the flexible line would not hold its position.  On top of that even though these nozzles were blowing 74 SCFM of compressed air at 80 PSIG, the blow off was ineffective and left moisture on the parts after the run, which lead to corrosion on the parts during storage.



The (2) six inch Air Knives improved this process in three ways.  First, he never needed to reposition the nozzles after a production run.  Using the 1/4-20 threads in the bottom of the air knife, the customer was able to mount the air knife directly to the machine, which was a more robust system than the flexible liquid coolant hose. Second, the knives only consumed 35 SCFM of compressed air reducing his air consumption by half.  By utilizing the 40:1 amplification ration of the air knife, the customer had a much lower demand on the compressed air system, while getting the job done.  Finally, he left his customers happy with no corrosion marks on the parts after they had been stacked and delivered.  With no complaints about the quality at his customer, our customer will be able to improve his relationship with his customers and improve his business.



Dave Woerner
Application Engineer