Monitoring, Expected Life and Planned Maintenance of Anode Cells
By utilizing the proper anode monitoring techniques, coaters/metal finishers can determine the expected life of their anodes and better plan for maintenance of their system to prevent quality issues with the coating and unexpected downtime resulting from anode degradation.
Proper maintenance of the anodes is one area in Electro-coating that is often overlooked when maintaining the E-coat system; until it is too late. As anodes degrade they begin to lose mass and their efficiency to deliver the proper throw power to the tank is compromised. This leads to quality issues because of improper paint film builds. To compensate, you have to increase the voltage on the rectifier to insure proper coating. This process is repeated until the anodes are completely degraded or replaced. Isn't there a better way to determine when anodes need to be checked or replaced so that this maintenance can be planned? Most anode manufacturers give an expected life in hours at a certain current density. This data can be useful but not every E-coat system runs at the maximum current density; in fact most don't. So how do you know how much anode life is left? Some E-coaters just set a time: every 1 year, 2 years or 5 years depending on the anode and usage. This is not an exact science. There is a solution to the problem though.
Learning Station I: Process Control / Maintenance