Dye-Penetrant Examination (PT / DPI)

Dye-Penetrant Examination (PT / DPI)

‘excellent to detect surface breaking flaws of non-ferrous materials’

This method is used to reveal surface breaking defects by the bleed out of a colored or fluorescent dye.

The technique is based on the ability of a liquid to be drawn into a surface breaking defect by capillary action. This method is a generally low cost solution which is applicable on most solid materials and can be used for the inspection of newly fabricated products as well as on in-service components. Dye penetrant inspection may be applied under day light conditions using a red contrast dye for regular sensitivity flaw detection. When a high detection sensitivity is required the fluorescent method may be used under appropriate light conditions.


  • Cracks
  • Fractures
  • Pin holes in welds
  • Seams
  • Welding imperfections