Sections of pipe with drilled holes across the length are commonly used as blowoff and made of relatively inexpensive materials (such as black iron) and are easy to make but what many don't know is they waste compressed air and significantly increase operational costs.
Home made blowoffs aren't safe since the holes can be blocked and the noise levels require hearing protection.
Homemade Blowoff VS Super Air Knife
For a comparison, let's look at a 12" section of pipe with (23) 1/16" diameter drilled holes. According to the chart in the above image gallery, 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)
Now let's take a look at replacing the drilled pipe with our 12" Super Air Knife. At 80 PSIG (5.5 BAR) a 12" Super Air Knife will consume 34.8 SCFM (2.9 SCFM per inch). Using the same figure of $ 0.25 per every 1,000 SCF used, it would cost $ 0.52 / hr. to operate this Super Air Knife. (34.8 SCFM x 60 minutes x $ 0.25 / 1,000)
Drilled pipe operating costs: $ 1.31 per hour or $ 10.48 per day (8 hours)
12" Super Air Knife costs: $ 0.52 per hour or $ 4.16 per day (8 hours)
Cost Savings: Drilled pipe - Super Air Knife = $ 6.32 savings per day
A 12" Aluminium Super Air Knife sells for $ 613.00. If we take $ 613.00 divided by $ 6.32 (savings per day), we get a ROI where the Super Air Knife pays for itself in 97 days!
As you can see, easy is not always better. The drilled pipe that seems like a simple and easy fix can actually be quite wasteful when it comes to the true cost of ownership. By comparison, the Super Air Knife pulls in 40 parts room air to the 1 part compressed air that is consumed.
If you are using similar homemade blowoffs in your plant and would like to see how the EXAIR Super Air Knife can make a difference, let us help. Our products have been engineered to boost efficiency so your processes can operate more efficiently.