A few months ago, I took a phone call from a manufacturing engineer who worked at a large candy production facility here in the United States. Extra chocolate was dripping out of the candy molds onto the conveyor belt below. Within a few hours the belt was dirty enough they would have to stop the line and clean the residual chocolate off the belt.
The best solution I found was a 72” 316 Stainless Steel Super Air Knife. It worked great when powered at 60 psig inlet pressure. The laminar flow of the Super Air Knife was perfectly suited for this application. The knife was mounted between the mold and the belt to help solidify and blowoff the excess drips of chocolate. There was one drawback, the Super Air Knife was not needed to blow the belt continuously and the continuous demand was not desirable during peak production.
The simple solution for this was the EXAIR Electronic Flow Control, the EFC minimizes compressed air use by turning off the air when a sensor is triggered. Since there was a 4.5-minute time gap between each mold set this was a great solution. When the photoelectric eye saw a mold, it then told the solenoid valve to open and supply the knife with compressed air for 30 seconds while the mold was open and the excess chocolate would be dripping. See the Savings calculations below;
Without using the EFC
(* Using $ 0.25 per 1000 SCFM used)
- 72” Super Ion Air Knife = 165.6 SCFM @ 60 PSIG
- 165.6 SCFM x 60 minutes x $ 0.25 / 1000 SCFM = $ 2.48 per hour
- $ 2.48 per hour x 8 hours = $ 19.84 per 8-hour day
- $ 19.84 x 5 days = $ 99.20 per work week
- $ 99.20 per week x 52 weeks =$5,158.40 per work year without the EFC control
With the EFC installed (turning the compressed air off for 4 minutes 30 seconds with a 30 second on time = 6 minutes/hour compressed air usage)
- 165.6 SCFM x 6 minute x $ 0.25 / 1000 SCFM = $ 0.25 per hour
- $ 0.25 per hour x 8 hours = $ 2.00 per 8-hour day
- $ 2.00 x 5 days = $ 10.00 per work week
- $ 10.00 per week x 52 weeks = $520.00 per work year with the EFC control
This example illustrates, clearly, why choosing the EFC is a good idea. It has the ability to keep compressed air costs to a minimum and saves compressed air for use within other processes around the plant. With this type of compressed air savings, the unit would pay for itself in less than 3 months.
If you would like to see how we might be able to improve your process or provide a solution for valuable savings, please contact one of our Application Engineers.