One common application that we get calls for each and every day centers around maximizing compressed air efficiency. I recently got to work with a customer who was using an inefficient blowoff method and was looking to replace it with an engineered compressed air solution. They had a total of (8) extrusion lines, each with (3) modular-hose style flat nozzles installed. Before a cooling bath they had one nozzle remove some of the heat, then as the extruded material exits the water bath another (2) nozzles blowoff any residual water. They were maxing out their compressor’s peak operating capacity and pressure drops across the system were causing problems elsewhere in other processes.
They were operating each of the flat nozzles at 50 psi using a total of 17 SCFM per nozzle. We first calculated how much air the current method was using. The extrusion lines were run for one full 8-hr shift per day:
17 SCFM/nozzle x 3 nozzles/line = 51 SCFM per extrusion line
51 SCFM x 60 mins x 8hrs x 5 days x 50 weeks = 6,126,000 SCF
The extrusion lines accommodated product that ranged from 1”-2.5” wide. They wanted one single solution to use across all different products. We settled on (3) of our 110003 3” Super Air Knives. Let’s take a look at the compressed air requirement for (3) 110003 Super Air Knives, also operated at 50 psig.
A Super Air Knife will consume 1.9 SCFM/inch when operated at 50 psig:
1.9 SCFM/inch x 3 inches (per knife) = 5.7 SCFM/knife
5.7 SCFM x (3) total knives = 17.1 SCFM
17.1 SCFM x 60 mins x 8hrs x 5 days x 50 weeks = 2,052,000 SCF
Total savings per extrusion line – 6,126,000 SCF – 2,052,000 SCF = 4,074,000 SCF
4,074,000 SCF x 8 extrusion lines = 32,592,000 SCF
By replacing the (3) inefficient nozzles with EXAIR’s Super Air Knives, a whopping 4,074,000 SCF of compressed air is saved each year. With (8) total lines, this equates to a total of 32,592,000 SCF of compressed air. Most companies will know the cost of their compressed air usage per CFM, but a cost of ($0.25/1000 standard cubic feet) is a good baseline to use.
($.25/1000 SCF) x 32,592,000 SCF = $8,148.00 USD
By replacing (3) inefficient nozzles across all (8) extrusion lines with EXAIR’s industry leading Super Air Knife, they were able to save a total of $8,148.00 per year. In as little as (6) months, the Super Air Knives will have already paid for themselves!!
If you’ve been maxing out your compressed air system, don’t necessarily assume you need to increase your overall capacity. Put in a call to an EXAIR Application Engineer and we can take a closer look at the ways your using your compressed air throughout the facility. By replacing some inefficient methods with an engineered solution, we can help you save air and money!