How to control the temperature and composition of the zinc solution during hot dip galvanizing process
Author: Robby
The temperature and composition of the zinc solution in the hot dip galvanizing process are the key factors affecting the quality of galvanizing. The following are the methods to control the temperature and composition of zinc liquid:
1. Temperature control:
(1) Too high a temperature will result in increased evaporation of the zinc solution, increased zinc slag and harmful gases, and affect the quality of galvanizing.
(2) Too low a temperature will result in poor fluidity of the zinc solution, uneven plating and rough surface.
Therefore, it is necessary to control the temperature of the zinc liquid in the appropriate range. Generally, the heating method of electric furnace is adopted, and the temperature of zinc liquid is controlled by adjusting the power of electric furnace. At the same time, it is necessary to keep the temperature of zinc liquid stable and avoid fluctuation during the galvanizing process.
2. Ingredient control:
(1) Zinc content: The zinc content in the zinc liquid is one of the key factors affecting the quality of the galvanized layer. If the zinc content is too high, it will lead to roughness and increased brittleness of the coating; if the zinc content is too low, it will lead to uneven coating and easy to peel off. Therefore, it is necessary to control the zinc content in the zinc solution within the appropriate range. Generally adjust the zinc content by controlling the addition of zinc ingot.
(2) Aluminum content: Aluminum can refine the crystallization of zinc liquid and improve the corrosion resistance and aesthetics of the plating layer. However, if the aluminum content is too high, it will cause the plating layer to become brittle; if the aluminum content is too low, it will affect the refining effect. Therefore, it is necessary to control the aluminum content in the appropriate range. Generally, the aluminum content is adjusted by controlling the amount of aluminum ingot added.
(3) Iron content: Iron is one of the impurity elements in the zinc solution, if the iron content is too high, it will lead to the rough surface of the plating layer and decrease the adhesion; if the iron content is too low, it won't have an obvious effect on the quality of the plating layer. Therefore, it is necessary to control the iron content in the appropriate range. The iron content is generally adjusted by controlling the amount of iron chips added.
In short, in the hot dip galvanizing process, it is very important to control the temperature and composition of the zinc solution, which can ensure the adhesion, surface quality and corrosion resistance of the galvanized layer.