Liquid Penetrant Testing (PT)

Dye penetrant inspection (DP), also called liquid penetrate inspection (LPI) or penetrant testing (PT), is method used to check surface-breaking defects in all non-ferrous materials and ferrous materials.
LPI is used to detect casting, forging and welding surface defects such as hairline cracks, surface porosity, leaks in new products, and fatigue cracks on in-service .