3. Operating techniques, sequences of operations

3.1 Precleaning

Precleaning of parts is a separate stage from the actual inspection process. For this reason, it is generally not advisable to integrate it into the penetrant process line.

The materials and processes used to prepare and clean the surface before applying the penetrant must be chosen according to the pollution and residues present on the surface or in the discontinuities, due to the manufacture or operation of the part to be inspected. But, also according to the material, so as not to risk corroding, attacking or embrittling it, or affecting its mechanical characteristics and fatigue life....