5. Rinses

A surface treatment line is a succession of chemical or electrolytic treatments, separated by rinses. Rinsing has a dual purpose:

• remove the training film from the bath after immersion;

• act as a pollution barrier between two consecutive operations.

After emersion from a treatment bath, the treated metal material is covered with a film of "concentrated" solution, the thickness of which depends on the characteristics of the solution (concentration, viscosity, temperature, surface tension, etc.) as well as those of the material (geometric shape, roughness, etc.). Rinsing a surface therefore involves diluting this thin film of solution, i.e. reducing the concentration of the solution's mineral skeleton, but also destabilizing emulsions. To improve rinsing, it is advisable to...