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
justinnicholl@exair.com
@EXAIR_JN

 

Don’t Waste Your Money (or Compressed Air)

This week I worked with a customer trying to separate a 135” wide paper sheet from a fabric used for commercial paper towel machines. They were using 45 spray nozzles, spaced 3” apart on a manifold, to blow off the sheet which then would fall into a chute below. The nozzles were doing the job but they were growing more concerned with their compressed air expense for this process.

Competitor Nozzle
45 pcs. of this nozzle were replaced with EXAIR’s Super Air Knife to save $87,000 annually!

The current nozzle setup was also causing another issue – there were “empty voids or gaps” in the airflow between the nozzles, which resulted in creases in the fabric. They were considering adding more nozzles and spacing them 2” apart but that was only going to increase their compressed air expense, so I asked them to consider our Super Air Knife. They were intrigued but were concerned that they would consume more compressed air, you’ll see below that the Super Air Knife uses less air and eliminates the creasing problem because the Super Air Knife provides a continuous airflow from end to end.

After reviewing the specs, I determined that each nozzle was consuming 29.6 SCFM @ 90 PSIG of compressed air, meaning they were consuming 1,332 SCFM for the process (29.6 SCFM x 45 nozzles).

I recommended using (2) 48” and (1) 42” Aluminum Super Air Knives, coupled together, to provide a 138” laminar sheet of airflow. I chose these In Stock – Ready to Ship lengths, so the customer wouldn’t have to order a special length even though that lead time would have only been 3 days. The Super Air Knife only consumes 2.9 SCFM @ 80 PSI (per inch of knife), and provides a laminar sheet of uniform airflow with a 40:1 air amplification rate, which would not only perform in the application, but also provide the needed compressed air savings.

SAK
What a great replacement for multiple nozzle manifolds! How SAK works

Using the above air consumption for our Super Air Knife, 2.9 SCFM @ 80 PSI (per inch of knife or 2.9 SCFM x 138”), I calculated the Super Air Knife consuming 400.2 SCFM @ 80 PSIG.

Since their process is a 24 hour operation, Monday – Friday, every week of the year, I calculated the following (* Using $ 0.25 per 1000 SCF used):

  • 45 nozzles x 29.6 SCFM = 1,332 SCFM @ 90 PSIG
  • 1332 SCFM (current) – 400.2 SCFM (EXAIR proposed) = 931.8 SCFM saved
  • 931.8 SCFM x 60 minutes x $ 0.25 / 1000 SCF = $ 13.98 saved per hour
  • $ 13.98 per hour x 24 hours = $ 335.52 saved per working day
  • $ 335.52/day x 5 days = $ 1,677.60 saved per week
  • $ 1,677.60 week x 52 weeks = $ 87,235.20 in yearly savings

After reviewing this savings with the customer, they mentioned they were glad they called because they were looking at increasing their air compressor size or purchasing another auxiliary unit. Now, they were not only going to save money on their current process, but they were eliminating the need to spend major funding on another compressor – not to mention the saved compressed air being available for future growth and processes.

At EXAIR, we commit to providing our customers with solutions to optimizing their current compressed air system.

Please contact an Application Engineer for optimizing your system today.

Justin Nicholl
Application Engineer
justinnicholl@EXAIR.com
@EXAIR_JN