DYE PENETRANT INSPECTION (DPI)
Dye penetrant inspection (DP), also called liquid penetrate inspection (LPI) or penetrant testing (PT), is a widely applied and low-cost inspection method used to check surface-breaking defects in all non-porous materials (metals, plastics, or ceramics).
CHEMETALL
Penetrant testing is a well-recognized inspection method to detect e.g. casting, forging and welding surface defects such as cracks, overlapping, folds, pinholes or other bonding failures