In the actual production process, the common factors that affect the speed and quality of galvanizing are:
1. The pre-treatment is not thorough. There is an oxide film on the surface of the workpiece, which affects the normal deposition of zinc.
2. Poor conductivity. The current is consumed on the wire, and the current distributed to the workpiece surface is too small.
3. The workpiece has high carbon content. High carbon steel, cast iron, etc. will reduce the hydrogen precipitation potential, the hydrogen evolution on the surface of the workpiece is accelerated, and the current efficiency is reduced.
4. The workpiece is too tightly bound. During galvanizing, the workpiece is partially shielded and the coating is too thin.
5. The temperature of the plating solution is low. When the temperature of the plating solution is low, the current density of the distribution decreases accordingly, and the deposition speed of the plating layer must also decrease.
6. The content of sodium hydroxide in the plating solution is too high. When the sodium hydroxide content is too high, the current efficiency decreases accordingly.
7. The additive content in the plating solution is low. The low content of additives will affect the dispersion ability, and the coating layer is too thin locally.
8. The area of the plated parts is underestimated, and the current density delivered during plating appears to be too small.
9. Improper hanging method of the workpiece, the distance from the zinc anode is too large, the position should be adjusted.
10. Workpiece is over corroded. Lowering the hydrogen precipitation potential, hydrogenation on the surface of the workpiece accelerates the current efficiency, thereby affecting the zinc deposition rate. An appropriate amount of corrosion inhibitor should be added to the pickling solution. If the scale is too thick at the local area, remove it first by mechanical method. During the pickling process, check more.
11. Anode passivation. The effective area decreases, affecting the normal distribution of current.
12. The content of sodium hydroxide is low. If the sodium hydroxide content is low, the current density is not high and the anode is passivated.
