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

Bottling Line Can Run Efficiently by Taking a Few Simple Steps

I recently visited a local customer who bottles a liquid drink.  They do two different sizes, single serve and gallon bottles.  The main issues they were having is the gallon bottles were not dry enough after they come out of a cooling / rinse tunnel.  They currently had three different blow off devices in place outside of this cooling tunnel.  The cooling tunnel had hundreds of spray nozzles to both rinse and cool the gallons of liquid.

On the exit of the tunnel there was a blower driven air knife that was being powered by a high maintenance motor that was also sucking in non filtered air to blow the moisture off thee gallon jugs.  The blower was not producing high velocity air and the knife position could not be adjusted for maximum effectiveness due to the hard piping from the blower.

The bottles come out of the blower and go from a 60″ wide conveyor to a 24″ wide conveyor in about five feet of travel. The bottles are then funneled down even further into a single file line and then sped up and sent through two 90 degree bends to try and knock any residual water off them before going into the casing machine.

There were no other blow offs on the gallon line because they were concerned with their compressed air use.  The other two blow offs they had in place were on the single serve bottling line. On that line there were two points that had six separate clusters of a metal flat nozzle that was approximately 1″ wide and were all pointed at a different point of the cap to try and eliminate some moisture that would get trapped under the lip.

The single serve bottles would come out spaced approximately six inches apart but the nozzles were blowing continuously.  This was a very large waste of compressed air.  They could have very easily installed an EXAIR EFC on these supply lines to cut their usage by more than 50% of their current demand.   They then went past an open pipe blow off to help dry the final labeling point.   This was also on continuously which was another opportunity for air savings.

I recommended installing two Electronic Flow Control (EFC) units and replacing their existing nozzles and open pipe with the EXAIR model 1126 1″ Flat Super Air Nozzle outfitted with swivels to allow them to be positioned properly to reach under the bottle cap. Proper positioning, in many cases, increases the effectiveness of the nozzles and can get the job done with fewer nozzles installed. In this application I am confident we can get that bottle cap area blown off with only 2 nozzles.

By eliminating excessive nozzles and cycling compressed air on and off only as needed, the customer saves compressed air. I estimated it was enough compressed air to install a 24″ Deluxe Super Air Knife Kit to blow down on top of the gallon containers, which is the primary reason they asked me to visit in the first place. This will not only give them the 24″ Super Air Knife, but it will also include the crucial EFC and a filter separator to clean the compressed air and a pressure regulator to adjust the pressure down to the minimum necessary for success. All of these factors contribute to optimizing compressed air and using it effectively within anyone’s plant:

  • Eliminate open pipes and ineffective blow offs
  • Turn off compressed air whenever possible
  • Keep it clean to reduce wear and maintenance
  • Adjust the pressure to a minimum level for success

This is just one location in the entire facility where implementing the Electronic Flow Control and EXAIR engineered nozzles will help the customer to optimize their compressed air use.

If you would like to learn more or have questions on any of the EXAIR products mentioned in this blog, feel free to contact us.

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF