On a recent trip to Europe, I was invited to visit a packaging manufacturer who was using EXAIR equipment in a variety of applications. This particular application dealt with the cooling of metal spray cans after they were welded on the seam that runs the length of the can form and after that same seem had been sprayed with lacquer and dried using hot air to keep the welded seam from rusting.
The cans were formed into their round shape from a flat sheet that had all the artwork applied. Then, using a magnetic conveyor similar to the photo on the right above, the machine moves the can form past a welding head to secure the two sides together. The welding process puts quite a bit of heat into the metal and so the customer immediately cools the can with a 72” Aluminum Super Air Knife for that same distance along the travel of the conveyor. The can then enters an area where there is a small spray applicator to add the lacquer to the welded joint. After that, the can traverses through a heated tunnel to dry the lacquer. Finally, the can is cooled by another set of Aluminum Super Air Knives as you see in the photo below.
The heat affected area was quite small in relationship to the airflow area that was generated by the Super Air Knife at a few inches distance away from the can form. So, the cooling power that could be developed with a large quantity of regular, room temperature air was quite sufficient to get the can form to cool to the proper temperature before moving on to the next operation.
The Super Air Knife in this application was operating at 1 BARG inlet pressure and provided continuous coverage all along the cooling length of the conveyor. By cooling this metal seam quicker, the customer was able to increase their throughput on this process by roughly 30%.
Neal Raker, International Sales Manager