“We are establishing a small batch powder coat operation. I need a complete “course” on the chemistry of pretreatment in a five or six tank immersion system; i.e., cleaners, iron phosphate, pH control, analysis of rinse water, non-chromic sealer, pH control. In other words we know nothing about powder coating and the learning curve could be a challenge. Can you steer us in the direction of good information?”
“Standard daily tests for pretreatment are called titrations. Titration procedures are dependent upon the actual chemistry used in the cleaning system. Since each pretreatment chemistry is proprietary, all titration procedures are unique and are developed by the pretreatment chemical supplier.
Frequency of the titration checks depends upon product throughput, product quality, and soil load. When checking to ensure that solutions are within controls, the rule of thumb is that no intervention (adjustment of chemicals) should be required for two out of three checks.
The other powder coating system checks depend upon many things. For instance the type of equipment, the quality requirements, customer specifications, etc. Things, like oven temperatures, powder output, booth performance, powder usage, etc. can be helpful in ensuring that the system is operating properly and doesn’t require maintenance.
The Powder Coating Handbook describes test procedures used to verify product quality. Furthermore, we have written many articles dedicated to this topic. We have also assisted many clients in determining what testing should be performed on their products. For further info, contact us for help or buy the Powder Coating Handbook as described in our reference section.”