Cooling Efficiently

Last week, I had the opportunity to work with a customer who was trying to cool a thermoformed film from 85° C (185° F)  down to room temperature, 21° C (69.8° F) or low enough for the package to be handled by an operator. This container was 270 mm X 170 mm X 100 mm (10.63″ x 6.69″ x 3.94″)

 

In applications like this, the customer often calls in with the idea of using a Vortex Tube to produce the cold air.  There are two reasons to use a different product than a vortex tube in this application. First, a vortex tube is only going to cool a small area, so to cool anything this size would take several vortex tubes.  Second, the cold air is going to mix with the ambient air very quickly. When the ambient air mixes with the cold air from the vortex tube, the air will lose the cold temperature generated by the vortex tube. To counter act this mixing, we have had customers create an insulated container to hold cold air from a vortex tube close to a product, similar to a cooling tunnel. This works in some applications, but my customer had a continuously moving line. He did not have time to stop the line and install insulation around each product.  He also didn’t have the length of conveyor needed to put a cooling tunnel over the line.

Super Air Knife Promo

Instead of using the vortex tube, I suggested that he use a 12” (305 mm) Super Air Knife to cool the thermoformed container. The 12” Super Air Knife moves significantly more air than a vortex tube over the surface of the part. Thanks to the 40:1 amplification ration of the Super Air Knife, it creates more cooling to the product and use less compressed air than a series of Vortex Tubes.  By mixing a large volume of free ambient air, that is the same temperature he needs to cool the part to, and a small amount of compressed air over the product they can easily cool their part to close to ambient so the operator can handle the part. The best benefit for this customer was they would not need change their manufacturing line.  The air knife is the best choice when cooling a very hot, fairly flat, large surface part to a temperature close to ambient. If you need to cool a product to a temperature lower than room temperature, then a vortex tube would be a great product to do the job.

Dave Woerner
Application Engineer
DaveWoerner@EXAIR.com
@EXAIR_DW

Super Air Knives Provide Needed Blow Off

Dust hood

I had the pleasure of working through an application in which uncooked hamburger buns are processed and baked.  In the application, dough patties travel along a conveyor into an oven and a small, targeted blow off (technical term: “fluff”) is needed to remove excess flour.

When the flour is blown off of the dough, it is extracted by a system mounted above the conveyor.  The difficulty for this end user was in finding a reliable, laminar solution with consistent blow off force.

Enter the EXAIR Super Air Knife.

By installing an EXAIR Super Air Knife (in the appropriate material), the uneven and inefficient blow off that was originally installed was replaced with a reliable and quiet solution.  We were able to take a problematic application and turn it into a repeatable process.  And, we were able to repeat success in another similar application at another point in the same facility.

If you have an application in which repeatable, reliable, efficient solutions are needed, contact an EXAIR Application Engineer.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE

EFC Can Provide Valuable Compressed Air Savings

I recently worked with a customer who was wanting to use one of our 72” Super Ion Air Knife is his paint booth application. He would be using the Super Ion Air Knife to remove any static build up and blow dirt/debris off ABS plastic molds (truck beds) prior to the paint booth. We were both confident the Super Ion Air Knife would perform in the application but he was concerned with the amount of air he would be wasting in between paint cycles. The paint time for each mold is 5 minutes and the blowoff time is 30 seconds, he was planning to leave the knife run during this time. This is an 8 hour per day operation, Monday – Friday, so this practice was going to lead to an expensive waste of compressed air*. I recommended that he incorporate our EFC (Electronic Flow Control) into his process.

Without using the EFC

(* Using $ 0.25 per 1000 SCFM used)

  • 72” Super Ion Air Knife = 208.8 SCFM @ 80 PSIG
  • 208.8 SCFM x 60 minutes x $ 0.25 / 1000 SCFM = $ 3.13 per hour
  • $ 3.13 per hour x 8 hours = $ 25.04 per 8-hour day
  • $ 25.04 x 5 days = $ 125.20 per work week
  • $ 125.20 per week x 52 weeks = $6,510.40 per work year without the EFC control

The EFC is an electronic flow control that minimizes compressed air usage by incorporating a timing controlled (0.10 seconds to 120 hours) photoelectric sensor. The unit will turn off the compressed air supply when there are no parts present and provides an easy way to program the device to a specific application. The EFC offers an additional eight programmable on/off modes and is suited for NEMA 4 environments. It can also be easily wired for electric, 100-240VAC, 50/60Hz.

EFCp4

With the EFC installed (turning the air off for 4.5  minutes with a 30 second cycle time = 6 minutes/hour compressed air usage)

  • 208.8 SCFM x 6 minute x $ 0.25 / 1000 SCFM = $ 0.31 per hour
  • $ 0.31 per hour x 8 hours = $ 2.48 per 8-hour day
  • $ 2.48 x 5 days = $ 12.40 per work week
  • $ 12.40 per week x 52 weeks = $644.80 per work year with the EFC control 

$ 6,510.40 per year (w/o EFC) – $ 644.80 per year (w/ EFC) = $5,865.60 projected savings per year by incorporating the EFC.

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.

Justin Nicholl
Application Engineer
justinnicholl@EXAIR.com
@EXAIR_JN

Super Air Knife – Dip Tank Application

I took a call from a customer today who was having a problem with residual fluid “pooling” on top of their parts after a heat treat dip tank application. After the parts are treated and removed they have to be set aside for an operator to walk around the tray with an air gun and manually blow off the parts, resulting in the fluid ending up on the shop floor. They were looking for a solution to effectively blow off the residual fluid prior to the trays being removed, so they could recover the excess fluid back in to the process and their operator could tend to other areas of production.

Heat Treat Equipment

I recommended using 2 of our 30” Super Air Knives. The Super Air Knife produces a high velocity laminar sheet of airflow with a 40:1 amplification ratio (the ratio of entrained ambient air to compressed air) and only consumes 2.9 SCFM (per inch) @ 80 PSIG. Engineered for safety, they cannot be dead ended – meeting OSHA standard 1910.242(b) and they also meet the OSHA allowable noise exposure operating at a low 69 dBA (@ 80 PSIG).

Capture

By mounting 1 of the units on the front and the other unit on the back of the tank, they would be able to pass the tray through the high velocity airflow providing the desired blow off and recovery of the fluid. More importantly, the customer was able to eliminate the unsafe, wet floor, work environment.

If you have a similar application or would like to discuss your process, please feel free to contact us. We are always ready to help.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN