LIQUID PENETRANT INSPECTION (WORKING PRINCIPLE (4) Developer Application,…
LIQUID PENETRANT INSPECTION
4) Developer Application
2) Penetrant Application
1) Pre-Clean of subject material/component.
3) Excess Penetrant Removal
WHAT IS NEEDED?
Tested on smooth and non-porous surface
Required Penetrant Properties
Penetration, Fluidity, Stability, Washability, Drying characteristics, Wetting ability, Dye concentrate, Viscosity
Example of penetrant materials are dye penetrant and fluorescents penetrant
Methods removing excess penetrant
Capillary action in a confined or small space
Penetrant on the tested surface has required wetting properties
Excess penetrant removed from surface
Inspect the tested surface
Reveal surface breakig flaws by bleed out of fluorescent from the flaws by capillary action.
Capillary action is tendency of liquids to penetrate into small openings such as cracks.
Developers used to pull trapped penetrant out of defects
Solvent based (Non aqueous)
Wet (Suspended in water)
Wet (Soluble in water)