Liquid penetrant testing is a non-destructive method used to detect surface breaking defects in any nonporous material. Liquid penetrant is applied to the surface and is drawn into defects by capillary action. Once a preset dwell time has passed, excess penetrant is removed and developer applied to draw out penetrant from defects. Visual inspection is then performed. Visible and Fluorescent Liquid Penetrant Examinations are Non-Destructive methods of revealing discontinuities that are open to the surfaces of solid and essentially non-porous materials, ferrous or non-ferrous.
Heat affect zone cracks
Poor weld penetration
Heat treatment cracks
Stress corrosion cracks
Section of material with a surface-breaking
crack that is not visible to the naked eye.
Excess penetrant is removed.
Developer is applied, rendering the crack