7. Characteristics of phosphating plants

7.1 General

For spray and peel installations, please refer to the article Surface treatment of metals prior to application of organic coatings. Process .

In the case of immersion, the following factors must be taken into account for the proper operation of a bath with a given formulation:

• concentration (AcT ) ;

• ratio of total acidity (AcT ) to free acidity (AcL ) ;

• gas pedal or Fe ²⁺ content;

• immersion time ;

• temperature to ± 2 to...