Quality Inspection and Acceptance Standards for Pre-coated Color Galvanized Steel Sheets
Time：2025-08-20
Quality control of pre-coated color galvanized steel sheets must 贯穿 the entire process from production to acceptance. Core inspection items include appearance, coating performance, and substrate performance.
Appearance inspection requires ensuring no surface defects such as bubbles, pinholes, or scratches, uniform color, and glossiness within the range of 30-40 as required.
Coating performance testing focuses on adhesion (tested by cross-cut method, no peeling is acceptable), salt spray resistance, and aging resistance. PE coating requires salt spray resistance ≥1000 hours, while PVDF coating requires ≥2000 hours.
Substrate testing includes galvanized layer weight, steel grade composition, and dimensional accuracy. The galvanized layer weight must meet contractual agreements, and sheet thickness deviation should be controlled within ±0.02mm.
During acceptance, it is also necessary to verify the quality certificate provided by the manufacturer to confirm that all indicators meet industry standards. When necessary, third-party organizations can be commissioned for sampling testing to ensure product quality meets standards.
