Surface preparation water: requirements and features

The most important stage of powder painting is the preliminary preparation of the metal before painting. Without this, even the highest quality paint will not provide an even and durable coating.

To remove dirt, degrease, wash and phosphate the metal before applying the coating, the metal must go through the surface preparation line.

In turn, it gets into different baths, which ensure high-quality cleaning of the product. In order for the chemical surface preparation to be of high quality, a large amount of water is needed. And from precisely it affects the final result of processing the product. We will talk about it in detail in this article.

Water requirements

The most important thing to control is the level of contamination of the flush fluid. Dirty water simply cannot clean the parts immersed in it well.

You should also pay attention to the hardness indicators, and the content of soluble and suspended substances.

Do not completely rinse products with water with high hardness (more than 250 million CaCO3). Do not use water that contains more than 100 mln. Of chlorides and sulfates.

The metal should be washed in demineralized water purified by ion exchange or reverse osmosis. For small lines, the first method is better.

Surface preparation for coating takes place in several stages and each of them requires different water:

• For alkaline degreasing, raw water is suitable, which does not form scale. It is best to mix tap water and demineralized water.
• The cheapest raw water that does not form scale is suitable for intermediate rinsing.
• For phosphating, you can use only distilled raw high-quality vodka or add demineralized vodka to it.
• Only demineralised water is suitable for the final rinse.

Demineralized water can be saved by using recirculation spray. It can immediately drain into the drainage channel, but it is better to demineralize it again.

By saving water at every stage, you can significantly reduce the costs that are needed to prepare the surface of metal structures for painting.

It is better to use the water many times while maintaining its quality. For this, a circulating water supply can be installed.

Be sure to follow the recommendations. Water is the main ingredient in metal preparation. And without proper cleaning, powder paint will not create a good finish.