The Society for Nondestructive Testing & Certification of Taiwan (SNTCT)

Non-destructive testing is a branch of modern engineering that detects or monitors flaws in the materials of structures before they affect their usability. In the welding of components or casting of components, cracks or slag may occur, which will change the material properties, reduce the strength, and cause damage and shutdown, endangering safety. Therefore, non-destructive testing is an effective technical tool for quality assurance in the manufacture and processing of structural materials, and can also be used to evaluate the service life of operating equipment.

Non-destructive testing integrates theories and engineering knowledge of various subjects such as physics, chemistry, mathematics, electromechanical, etc., and uses professional testing instruments or media materials to display defects or abnormal phenomena existing inside and outside the material. A series of operating procedures for analyzing, evaluating or judging from the displayed signals, images or parameters. There are many methods and techniques, and there are nearly a hundred kinds of current users. From the visual method of detecting the surface of the object, to the more complex technology of radiography, ultrasonic detection, thermal imaging, and even positron imaging technology and so on. It can be used for direct contact detection, indirect isolation detection or long-distance telemetry.

Non-destructive testing has a wide range of applications, and can be used for testing individual objects of various materials, sizes or shapes or processed by different processes; continuous inspection on automatic production lines, or shutdown maintenance inspection. It is also possible to measure the physical properties of materials, or the internal pressure changes of structures in use. The main application areas cover nuclear energy, petrochemical pipelines, pressure vessels; steel welds for hulls, bridges, and towers; electromechanical components for aerospace and transportation vehicles; and even civil and stone structures, etc., too numerous to mention.

The most important feature of non-destructive testing is that during the testing process, the structure and performance of the structural material will not be damaged, and its scale shape will not be changed. Under this definition, its content includes multi-level functions such as inspection, testing, detective, monitoring, and even analysis and evaluation. There is another term called nondestructive testing in Chinese, and there are Nondestructive-Testing (NDT), Nondestructive-Examination (NDE), Nondestructive-Inspection (NDI), and Nondestructive-Evaluation (NDE) in international terms.