Hot-dip galvanizing of products with overlapping connection
In the case of construction of things that will be subjected to galvanizing, it is better to prevent the formation of small gaps between the parts, that is, overlapping connections, if possible. When space is less than 2.5 mm, the viscosity of the zinc does not allow it to move. Zinc will not enter the holes, but less viscous solutions will be able to enter. This may contribute to the release of iron oxide from the gap.
Steel during galvanizing is heated more than 400 C. correctly installed ventilation for interacting products overlap, will not provide the formation of moisture or gas in the steam at the time of heating. Moisture that is formed can cause damage to the product or the creation of uncovered areas.
Complications during galvanization of closely connected surfaces:
- Transformation into a pair of cleaning solutions when lowering the parts in a zinc bath. This will cause the appearance of uncovered areas.
- Unsatisfactory washing leads to the accumulation of salts of the cleaning solution. Rusty plaque is formed on the zinc coating due to the impact of air humidity on the surrounding area, and as a result there is salt impregnation.
- It is impossible to use only cleaning solutions to reliably clean the gaps between the surfaces of oils and lubricants. Due to the high temperature of galvanizing there is a partial purification from oils and greases. But in this case you will get the coverage of poor quality.
Contact our specialists for advice! You will be able to avoid problems, learn a lot of new information about lap joints, including ventilation openings.