Regarding the question by B.F. (January 2011) concerning spot weld drag marks: While your answer was certainly correct, the question may still not be completely answered.
Our client has an RTO on its aluminum window frame painting line, and we supplied a total hydrocarbon analyzer to meet compliance. We get a huge spike in the readings when the RTO chambers cycle every four minutes. We can go from 3 to 6 ppm for four min, then spike to 400 to 1,000 ppm for a few seconds. I don’t believe RTOs should work that way and that switching should have little or no effect on efficiency. I think the client’s unburned paint is contaminating our gas analyzer.
We are concerned about paint adhesion on equipment cabinets made of mostly 41003 (a utility-grade stainless steel that is 12 percent Cr) and either 304 or 201 for the hard-to-draw parts.
We are using a mil spec polyurethane topcoat, MIL-PRF-85285, on an electronics housing, and I am trying to find a reference indicating that this topcoat is fungus-resistant.