DYE PENETRANT INSPECTION
Non-destructive, dye penetrant inspection is a method used to detect surface-breaking discontinuities in solid and non-porous materials. This technique allows the inspection of large surfaces in a simple and fast way, with great efficiency for most industrial applications.
The DPI method consists of applying, on the area to be inspected, a low viscosity colored liquid that can penetrate cracks or pores through capillarity. The excess liquid must then be removed until the surface is clean. Finally, a white liquid to reveal the flaw is applied to extract the penetrant that has entered the discontinuity. Thus, any surface defect is revealed with high contrast, facilitating its identification in the visual exam.
This type of testing is widely used to identify failures in weld beads, structural components, high-stress subjected parts, gears, among others.