The powder coated surface should be delicate, full, transparent, strong in three-dimensional sense, and can maintain relative luster for a long time. The decorative surface coating is at least 40um. The poor appearance is dim, the stereoscopic effect is poor, and after a period of time, there is light loss, powdering, paint stripping, etc. Slight orange peel on the surface of powder coated profiles is accepted. There are almost no orange peels on high-quality powder coated profiles, but the orange peel on the surface of poor powder coated profiles is obvious and serious. The reason is the use of poor quality powder coatings, or the production process and production management are not strict.