Cost Saving Example 2

$5,012.28 Annual Air Savings For Pre-Paint Bumper Cleaning

A manufacturer of car bumpers installed a 60” (1524mm) Super Ion Air Knife in the down draft cleaning area prior to their paint booth. The bumpers enter that area in the same orientation as they would when mounted to the automobile, moving at 3m (10-foot) per minute with a 12” (305mm) space between bumpers. The bumpers are under the blowoff for 10 seconds. 6 seconds pass with no bumper in the ionised airflow. The operation runs around the clock with three shifts.

The timer was set to “interval” and the sensor mounted next to the Super Ion Air Knives. When it detected a bumper, it immediately turned on the air for 10 seconds. If the conveyor stopped, it would not turn the air on again until it detected the next bumper.

Old Method

EXAIR’s 60″ (1524mm) Super Ion Air Knife was supplied at 40 PSIG to clean the bumper.
At 40 PSIG, EXAIR’s 60″ (1524mm) Super Ion Air Knife consumes 102 SCFM (2,887 SLPM).
Non-stop blowing of 1,440 minutes (24 hours) per day x 102 SCFM = 146,880 SCF (4,156,704 SL) air usage per day.

EFC Solution

The EFC was installed to shut off the compressed air for the 6 seconds where no bumper was present – an on-cycle reduction of 37.5%. 1,440 minutes x 37.5% = 540 minutes of off time per day

Cost Difference

Most large plants know their air cost. If the actual cost is unknown, $0.25 per 1,000 SCF (28,329 SL) is reasonable.

Before the EFC installation:
146,880 SCF/1,000 = 146.88 x $0.25 = $36.72 air cost per day.

With the EFC installed:
146,880 SCF x 62.5% on cycle = 91,800 SCF/1,000 = 91.8 x $0.25 = $22.95 air cost per day
$36.72 (old air cost) – $22.95 (new air cost)
= $13.77 savings per day x 7 days per week
= $96.39 savings per week x 52 weeks per year
= $5,012.28 savings per year