Replacing Water Cooling With Air Amplifiers

Copper tubing in need of air-powered cooling

The copper tubing shown above is heated in an annealing furnace to a temperature of 175°C (347°F).  This tubing is stacked on racks in 100kg rolls, with 4-6 rolls of copper per rack, and then fed into the oven shown below.  When the tubing exits the oven, water is used to cool the copper to a temperature of approximately 35°C (95°F) with an ambient temperature of ~20°C (68°F).  While effective, the use of water to cool the copper is something the manufacturer would like to replace due to constant maintenance, safety issues and cleanup time, preferring instead to use air to provide the required cooling.

The copper tubing travels through this oven
The racks used to stack the copper tubing

I’ve blogged before about the process of determining how much air volume is needed to remove a specific amount of heat.  (You can read previous blogs here and here.)  This application was no different, and I used the flow chart shown below to determine the volume of 20°C ambient air needed to cool this aluminum.

heat load calc process
Airflow calculation process

Using the process outlined above, I determined the application would need 1,133 CFM of air at 20°C to cool these copper coils in one minute. This application, however, has up to 20 minutes available to cool these coils, allowing for a reduced volume of air.  Extending the time available to 2 minutes, and thus reducing the volume requirement to 566.5 CFM (566.5 CFM for 2 minutes = 1,133 CFM for 1 minute), we can definitively say that a series of our model 120022 Super Air Amplifier will be able to provide ample cooling.  (See below for airflow from model 120022 at 5.5 BARG (80 PSIG) at a distance of 6” from the Air Amplifier outlet.)  And, in order to evenly cool the coils, (4) of these Air Amplifiers were recommended, distributed evenly around the coils.

Performance for model 120022 operated at 80 PSIG shown in the red circle on the right

Using a bit of calculation, we were able to provide a specific solution for this customer, eliminating the need for water in the cooling phase of this application.  If you have a similar application, or would like to discuss a compressed air solution for your application, contact an EXAIR Application Engineer.

Lee Evans
Application Engineer

EXAIR Cold Gun Provides Dry Cooling for Gang Drill

A gang drill in need of dry cooling

When working with machining centers of any sort, proper cooling is critical to producing in-spec parts.  Inadequate cooling deteriorates the tooling and can lead to defective or rejected parts, so most of us try to avoid overheating whenever possible.  Traditionally, the best way to cool the cutting blade or bit of a machining center was to use liquid coolant, routing the liquid to the required areas of the machine, and then reclaiming the coolant to be used again while cleaning the finished parts of the coolant residue.

This process, while effective, creates a considerable amount of cleanup, both for the machining area, and for the machined parts.  Because of this, dry cooling can provide distinct advantages when compared to a traditional setup.

Liquid cooling spilled onto the floor as a result of machining operations

In the setup shown above, a gang drill with 24 drill heads cuts into various aluminum profiles.  As shown in the picture, the process generates a significant strings and chips, and the current setup using liquid cooling results in coolant outside of the desired workspace (see the red arrow in the bottom right, highlighting liquid coolant on the floor – a potential safety hazard).  The end user in this case was in search of a way to maintain cooling for the drills while eliminating the liquid spillover.  The solution, was the EXAIR Cold Gun model 5315 with two cold outlets

When faced with the potential to outfit a machine with a completely new cooling system, we’ve found that a short test can go a long way toward implementing a proper solution.  So, testing a single Cold Gun with two outlets can be tested on a single drill head, with the results reviewed before installing additional units onto the machine.  Our Application Engineering team is available to assist this customer every step of the way with product selection, installation and testing results, and full machine outfitting.

Providing a viable solution and service to the customer have opened the door to removing liquid cooling from this machine.  This will eliminate cleaning of the aluminum profiles after machining, thus reducing the total input required to produce a finished product, and it will eliminate the safety hazard of having liquid coolant on the floor surrounding the machine as well.

If you have a similar application or would like to speak to an Application Engineer about dry cooling, give us a call – we’ll be happy to help.

Lee Evans
Application Engineer