11510 Goldcoast Drive • Cincinnati, OH 45249-1621 • Phone (513) 671-3322 FAX (513) 671-3363 • E-mail: [email protected] • www.exair.com 9 EXAIR Optimization EFC $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 auto- mobile, moving at 10' (3m) per minute with a 12" (305mm) space between bumpers. The bumpers are under the blow off for 10 seconds. 6 seconds pass with no bumper in the ionized 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. $3,393 Annual Air Savings On A Tank Blowoff Operation A company that refurbishes large tanks runs the tanks through an oven on a conveyor line to burn off old paint. Only one tank at a time can be processed and each takes 6 minutes to complete the journey. Super Air Knives are used for blowoff at the exit of the oven. However, the tank travels through the oven for 5 minutes before it reaches the knives for blowoff. At 80 PSIG (5.5 BAR), the four knives consume 348 SCFM (9,854 SLPM). Once the tanks have been blown off, the conveyor stops, the air is shut off, and a new tank is loaded at the other end. The operation runs 30 tanks per day, 5 days a week. The timer was set to “on/off delay”. The sensor was mounted at the oven exit (1 minute away from the blowoff station). When the sensor detected a tank, the timer turned the air on for one minute, just as the next tank reached the blowoff station. 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 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. Old Method It takes 6 minutes to complete the process. 6 minutes x 348 SCFM= 2,088 SCF (59,090 SL) 2,088 SCF x 30 tanks = 62,640 SCF (1,772,712 SL) EFC Solution The EFC was installed to shut off the compressed air for the 5 minutes where no tank was present (one minute of air on). 1 minute x 348 SCFM = 348 SCF x 30 tanks = 10,440 SCF (295,452 SL) 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: 62,640 SCF/1,000 = 62.64 x $0.25 = $15.66 air cost per day. With the EFC installed: 10,440 SCF/1,000 = 10.44 x $0.25 = $2.61 air cost per day. $15.66 (old air cost) – $2.61 (new air cost) = $13.05 savings per day x 5 days per week = $65.25 savings per week x 52 weeks per year = $3,393 savings per year.
