1. Poor conductivity. The current is consumed on the wire, and the current distributed to the surface of the workpiece is too small.
2. The workpiece contains high carbon content. High carbon steel, cast iron, etc. will lower the hydrogen evolution potential, accelerate hydrogen evolution on the surface of the workpiece, and reduce current efficiency.
3. The workpiece is tied tightly. Part of the workpiece is shielded during galvanizing in iron drum packaging, which results in too thin coating.
4. The bath temperature is low. When the temperature of the plating solution is low, the distributed current density will decrease correspondingly, and the deposition speed of the iron drum packaging coating will inevitably decrease.
5. The sodium hydroxide content in the plating solution is too high. When the sodium hydroxide content is high, the current efficiency decreases accordingly.
6. The content of additives in the plating solution is low. The low content of additives will affect the dispersion ability, and the coating of the iron drum packaging appears too thin.
7. The area of the plated parts is under-estimated, and the current density distributed during plating appears too small.
8. The workpiece suspension method is improper, and the distance between the workpiece and the zinc anode is too large, and the position should be adjusted.
9. The workpiece is corroded. Reduce the hydrogen precipitation potential, and accelerate the current efficiency of hydrogen evolution on the workpiece surface, thereby affecting the deposition rate of zinc packaged in iron drums. Appropriate amount of corrosion inhibitor should be added to the pickling solution. If the local oxide scale is too thick, mechanically remove it first. Do more checks during the pickling process.
10. The sodium hydroxide content is low. If the sodium hydroxide content is low, the current density will not increase and the anode will be passivated.https://www.fhpails.com/