NDT (NON DESTRUCTIVE TESTING) :- Non Destructive Testing in great variety are in world wide used to detect variations in structure, minute changes in surface finish, the presence of cracks or other physical discontinuities, measure the thickness of materials and coatings and to determine other characteristics of industrial products. REASON'S FOR THE USE OF NDT: "NDT" is used by the manufacturers for the following reasons: 1. To ensure product reliability. 2. To make profit for the user. a) To ensure customer satisfaction b) To aid in better product reliability. c) To control the manufacturing processes. d) To lower the manufacturing costs. e) To maintain uniform quality level. SOME OF THE MOST COMMON NDT METHODS ARE : 1.VISUAL ...