In 1, the film gloss: curing baking time; high temperature; baking in mixed with other harmful gas; the workpiece surface too rough; improper selection of pretreatment method.
2, coating color: repeated baking in the oven; mixed with other gases; curing baking excessive.
3, film orange surface: spray coating is uneven; powder atomizing degree is not good, the spray gun has the phenomenon of accumulated powder; low moisture curing temperature; powder, powder particles is too thick workpiece; grounding; the baking temperature is too high; the film is too thin.
In 4, the paint have concave hole: improper handling, in addition to oil net; the source of contaminated, compressed air oil, water removal is not thorough; surface roughness; affected by dust or other contamination.
In 5, the film bubble : surface treatment, water is not completely dry, leaving before processing residue; degreasing, rust is not complete; the volatile matter not to net; the workpiece surface with holes; powder coating is too thick.
6, coating is not uniform: powder spray gun and the workpiece is not uniform; too close; high voltage instability.
In 7, the film impact strength and poor adhesion: phosphating film is too thick; curing temperature is too low, time is too short, so that curing incomplete; bottom metal untreated clean; coated workpiece will reduce the adhesion after immersion in water.
