September 26, 2023
Production line water quality requirements:
1. All process tanks must use deionized water or distilled water;
2. The cleaning water before and after passivation must use deionized water or distilled water; other cleaning water must meet the drinking water requirements of GB 5749.
3. The water flow in the cleaning tank should be countercurrent, or replaced regularly.
(Note: The water quality of deionized water or distilled water is required to reach pH = 5.0~7.5, and the conductivity is not greater than 10 μS/cm)
Chemical raw material requirements:
1. The chemical raw materials used in each process tank before electroplating must not be lower than the national standard requirements of the corresponding industrial-grade materials;
2. The chemical raw materials used in the electroplating solution must be no less than the national standards for corresponding chemically pure materials.
3. Suppliers of additives or passivators for electroplating must have good quality assurance capabilities.
In addition to having a chemical analysis laboratory, the manufacturer must also have at least the following testing instruments: thickness gauge, salt spray test chamber, adhesion testing tools and standard tape (in compliance with ISO 2409), and be able to perform qualified test operations. All testing instruments and equipment must have valid calibration certificates.
Dip coating facilities and operating requirements for hot dip galvanizing:
1. Parts that need to be sprayed with an organic coating after hot-dip galvanizing must be sprayed with an organic coating within 24 hours after hot-dip galvanizing, and it must be ensured that the surface of the hot-dip galvanized parts is not contaminated in any way.
2. The hot-dip galvanizing workshop should keep the environment clean and avoid dust, oil and other pollution.
3. All dip coating process tanks should be free of debris or oil. If sandblasting equipment is used, it should be oil-free and dust-free, and the compressed air used should be oil-free and water-free. (The operator can blow compressed air against a clean mirror for 2 to 3 minutes, and check that there should be no traces of oil or water on the mirror)
4. The storage area for finished parts should be clean and pollution-free, prevent rainwater from contacting the parts, and provide clean parts packaging.
5. Operators must wear clean gloves when touching parts.
6. Basic quality inspection and control equipment should be available. Various measuring instruments and instruments used in production and inspection must be ensured to be within the effective calibration period.
7. The components in each process tank must be regularly tested, analyzed and maintained to ensure that each component is within the specified range.
8. Measures must be taken to repair and coat the parts that are not immersed in the zinc layer; the repair paint used must be zinc-rich paint.