Nondestructive Testing (NDT) consists of a variety of non-invasive inspection techniques used to evaluate material properties, components, or entire process units. The techniques can also be utilized to detect, characterize, or measure the presence of damage mechanisms (e.g. corrosion or cracks). NDT is also commonly referred to as nondestructive examination (NDE), nondestructive evaluation (NDE), and nondestructive inspection (NDI). Many NDT techniques are capable of locating defects and determining the features of the defects such as size, shape, and orientation. The purpose of NDT is to inspect a component in a safe, reliable, and cost effective manner without causing damage to the equipment or shutting down plant operations. This is in contrast to destructive testing where the part being tested is damaged or destroyed during the inspection process.
NDT can be performed during or after manufacture, or even on equipment that is in service. In manufacturing, NDT inspections determine if parts are fit for a desired function. In other words, parts are inspected to ensure they will last a certain amount of time or cycles before failure. During operation, NDT inspections can be used to asses the current damage state of equipment, monitor damage mechanisms, and make informed decisions for remaining equipment life evaluations (e.g., RBI, FFS).