The pickling and annealing process of the hot strips consists of three main phases:
- Annealing: This can be done in passive furnaces, bell ovens, and directly in line. The aim is to release the internal stresses of the structure created during hot rolling.
- Mechanical pickling: This is carried out with a sandblaster and afterwards, with abrasive brushes.
- Chemical pickling: This is done in tanks with acid solutions (H2SO4 + HF).