If the workpiece turns black, it can be re-galvanized by cleaning, grinding, pickling and other treatments.
Author: Marisa
After the workpiece turns black, it can be simply cleaned and treated before galvanizing.
I. Reasons for the blackening of the workpiece
The reasons for the blackening of the workpiece may be due to the following aspects:
1. Oxidation: When the time is long, the surface will be corroded by the oxidizing gas in the air, and an oxidation reaction will occur, making the surface black.
2. Moisture: In a humid environment, iron will corrode and produce black oxides.
3. Welding: During the welding process, high temperatures may occur, causing the surface to burn and blacken.
II. Can the workpiece still be galvanized after it turns black?
After the workpiece turns black, if it is to be galvanized, it needs to be cleaned first and carried out according to certain treatment methods. In addition, it should be noted that if there are too deep pits, scratches, etc. on the surface, it will affect the adhesion of the plating solution and is not conducive to the galvanizing process.
III. Methods and precautions for processing workpieces
1. Cleaning: For dirt and dust on the surface of the workpiece, you can use a cleaning agent to clean it. After cleaning, you can dry it first or wipe it with absorbent paper.
2. Grinding: The blackened surface needs to be ground first to achieve a flat and smooth surface and improve the adhesion of the galvanizing.
3. Pickling: Use an acid cleaning solution for pickling to remove rust and oxides to prepare for the next step of electrolytic galvanizing.
Notes:
1. For deeper scratches or potholes, the anti-corrosion coating should be removed in advance.
2. The use requirements of cleaning agents and acid cleaning solutions must comply with national regulations, and attention should be paid to anti-corrosion measures and labor protection measures.
[Conclusion]
If the workpiece is blackened, it can be re-galvanized by cleaning, grinding, pickling and other treatment methods. At the same time, during the treatment process, attention should be paid to the use requirements of cleaning agents, acid cleaning solutions and labor protection measures. In short, as long as the technology is properly handled, blackened workpieces can also be galvanized.