Control tests

  • X-rays on day samples and piping in the field
  • Endoscopy or Fibroscopy with video recording on digital media
  • Laboratory metallographic analysis


The surface of all stainless steels, thanks to their particular composition, are able to develop a spontaneous capability to cover themselves with a film of chromium oxide, rendering it passive and therefore protected from corrosive processes.

This layer of oxide can undergo alterations during the processing of the metal or by corrosion caused by aggressive chemicals.

In order to eliminate all the processing residues (polishing, cutting, etc.), and to restore the layer of surface oxide altered during welding, we undertake:

  • Degreasing

    Removal of any trace of grease or impurities

  • Pickling

    Removal and dissolving of surface oxides

  • Passivation

    Removal of any traces of ferrous pollutants and restoration of the stainless properties.

At the end of this process, when the clean steel comes into contact with the air it will reform the passive oxide layer within a short period of time.

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