AFI is always trying to evolve to become a better company and the pretreatment process before painting is no exception. Metal parts are pretreated by using a chemical bath that etches the surface and applies a performance boosting coating. The application equipment and controls of this process are the keys to a consistent, high performing final coating. AFI is continuing to upgrade the process with new technology and relationships with vendors. How are your parts pretreated? That depends on the size and quantity of your order to determine the most efficient way to complete the pretreatment.
Tunnel Multi-Stage In-Line Washer
AFI uses the PEM Spraylean system to clean and pretreat smaller, high volumes of parts. The system’s modular design and flooded pumps make it more efficient than the traditional washer systems and it is placed along the conveyor to automatically wash parts as they pass through. The stages are easier to maintain and can be physically moved and adjusted as needed. The parts pass through these stages with high pressure nozzles applying cleaner and pretreatment solutions followed by rinses to prep for coating. The keys to keeping the baths maintained are the temperature, cleanliness, and concentration of the chemical in the bath. To maintain these parameters, AFI uses a combination of manual checks, electronic monitoring and automatic pumps. The concentration is monitored electronically and automatic pumps add cleaning chemi-cal as needed to always stay within the optimal range. We also manually check the titrations of the baths once a shift to ensure that the monitors and pumps are working properly.
SprayWand System
AFI uses the PEM SprayWand system to clean and pretreat larger or lower volume runs of parts. This sys-tem is a manual operation with a pressure washer type wand to apply the water and chemicals needed to pretreat the part. This system can be utilized to apply as many stages of cleaning and pretreatment as nec-essary to finish the job. It gives the operator the freedom to move around the part and fully pretreat the hard to reach areas. In this setup, the chemical is pumped out of the drum and added to the high pressure water to create the correct solution. The concentration of the chemical is controlled using patented orific-es that inject the chemical downstream from the pump. To verify this concentration, the solution is sprayed into a bucket and then titrated to check that the orifice is still allowing the correct amount of chemical through the wand.
If you would like to read more about pretreatment application check out Ted Schreyer’s fea-ture in Powder Coated Tough Magazine January/February 2019 Edition