EXAIR Super Air Knife: Reduce Cost, Reduce Noise, Increase Safety

This question from end user’s comes up again and again:

“I know EXAIR makes Air Knives. Do you have one for this application?”

We can answer, almost unequivocally, with a resounding “YES!” Whether we can meet the needs of the application with a stock product, or through manufacturing a specially made unit, we make every effort to provide the needed solution.

Super Air Knife Replaces Drilled Pipe Blow Off

Case in point, in the application above, a specific length Air Knife was desired to remove debris from material as it goes into a processing chamber. The current setup (outlined in red)  uses drilled holes in a section of pipe which are costly, loud, and unsafe.

How costly, you ask? Our customer stated this knife was 100″ long with 3/32″ holes on 2″ centers (50 holes). EXAIR test results on 3/32″ drilled holes confirm 15 SCFM per hole at 80 PSIG inlet pressure. The customer also estimates this drilled pipe operates for a total of 1 hour every day, 250 days per year. Using $0.25 per 1000 SCFM we can calculate the following:

  • 50 holes x 15 SCFM = 750 SCFM at 80 PSIG
  • 750 SCFM x 60 minutes per day = 45,000 SCF per day
  • 45,000 SCF x 250 days = 11,250,000 SCF per year
  • 11,250,000/1000 x $0.25 = $2812.50 cost per year

How loud, you ask? Our customer confirmed all personnel near the application were require to wear ear protection at all times. Though they were unable to provide a decibel (dBA) level, the need for hearing protection would indicate this pipe was operating in excess of 100 dBA.

How unsafe, you ask? Air can be dangerous when the outlet pressure of a hole is greater than 30 PSIG. In the event any of the holes were blocked by a hand or other body part, air may enter the bloodstream through the skin, resulting in serious injury. All of the Air Knives manufactured by EXAIR have been engineered for safety. They are all safe to be supplied with higher pressure compressed air and meet OSHA standard CFR 1910.242(b). Drilled holes in a pipe DO NOT MEET this OSHA standard.

Initially, discussions with this end user focused on a custom length, custom built Super Air Knife. Given the dimensions of the processing environment, we determined the desired length and the end user was thrilled we could not only make to their specifications, but offer 3 day delivery as well.

As the discussion carried on, we realized that the special length Super Air Knife, while applicable, was not a critical requirement for the application. With this new consideration, a stock length knife was chosen, and just like any stock EXAIR product, we had it on the shelf, ready to ship the same day.

This application highlights several benefits of the EXAIR Super Air Knife solution – compressed air savings, noise reduction, providing safety, and quick delivery. EXAIR Super Air Knives solve multiple problems for end users and OEM’s in a variety of applications.

Compressed Air Savings: 

  • 96″ knife with 2.9 SCFM per inch consumption at 80 PSIG = 278.4 SCFM at 80 PSIG
  • 278.4 x 60 minutes per day = 16,704 SCF per day
  • 16,704 SCF x 250 days = 4,176,000 SCF per year
  • 4,176,000/1000 x $0.25 = $1044 cost per year
  • $2812.50 (drilled pipe annual air cost) – $1044 (EXAIR 96″ Super Air Knife air cost) = $1768.50 SAVINGS the first year!

Noise levels reduced to under 80 dBA. 

SAFETY: EXAIR Super Air Knives meet the OSHA standard CFR 1910.242(b).

Switching this customer over to an engineered solution provided a win in these three important areas of any operation. If assistance is needed determining which Super Air Knife best suits your application, contact an Application Engineer.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE