Dye Penetration Test (DPT) is one of the simplest and oldest Non-Destructive Inspection methods. Also, known as the Liquid penetration test, the Dye penetrant test is widely used to detect surface discontinuities like cracks, fractures, porosity, grinding defects, incomplete fusion, and flaws in joints. This test or inspection method is serving as an aid to finding irregularities in aluminum, cast iron, brass, steel and stainless steel, copper, magnesium, carbides, stellite, ceramics, and even certain plastic materials. So, the dye penetration test is suitable for both ferrous and non-ferrous materials and highly economic as compared to the other non-destructive inspection methods.