What is Nondestructive Testing?

NDT is the abbreviation of non-destructive testing.

NDT refers to a method of testing materials or workpieces that does not damage or affect their future performance or use.

By using NDT, defects inside and on the surface of materials or workpieces can be found, the geometric features and dimensions of workpieces can be measured, and the internal composition, structure, physical properties and state of materials or workpieces can be determined.

NDT can be applied to product design, material selection, processing and manufacturing, finished product inspection, in-service inspection (repair and maintenance), etc., and can play an optimal role between quality control and cost reduction. NDT also helps to ensure the safe operation and (or) effective use of products.

NDT includes many methods that can be effectively applied. The most commonly used NDT methods are: radiographic testing, ultrasonic testing, eddy current testing, magnetic particle testing, penetration testing, visual testing, leak detection, acoustic emission testing, radiographic testing, etc.

Since various NDT methods have their own scope of application and limitations, new NDT methods have been continuously developed and applied. Generally, as long as it meets the basic definition of NDT, any physical, chemical or other possible technical means may be developed into an NDT method.

In China, the term non-destructive testing was first called flaw detection or non-destructive testing, and its different methods were also called flaw detection, such as radiographic flaw detection, ultrasonic flaw detection, magnetic particle flaw detection, penetrant flaw detection, etc. This name or writing method is widely circulated and has been used to this day, and its usage rate is no less than that of the term non-destructive testing.

Abroad, the English word corresponding to the term non-destructive testing, except that the first half of the word, that is, non-destructive, is mostly written in the same way, the second half of the word is written differently. For example, Japan is used to writing inspection, many European countries used to write flaw detection, and now use testing uniformly. In addition to using testing, the United States seems to prefer writing examination and evaluation. When these words are combined with the first half, the abbreviations formed are NDI, NDT and NDE. When translated into Chinese, different terms and writing styles appear, such as non-destructive testing, non-destructive inspection (non-destructive inspection), non-destructive testing, non-destructive testing, and non-destructive evaluation. In fact, these different English and their corresponding Chinese terms have the same meaning and are synonyms. To this end, the International Organization for Standardization Technical Committee for Non-destructive Testing (ISO/TC 135) has developed and issued a new international standard (ISO/TS 18173:2005) to unify these terms in different forms and writing styles, making it clear that they are terms with the same definition and are synonyms, that is, they are all equivalent to non-destructive testing (non-destryctive testing). The different writing styles are only due to different language habits.

Therefore, as a standardized term, it is recommended to use the term "non-destructive testing", and the corresponding English term is recommended to use "Non-destructive testing". The name of various non-destructive testing methods also recommends the use of the word "testing", such as radiographic testing, ultrasonic testing, magnetic particle testing, penetration testing, eddy current testing, etc. When translating, it is recommended that English words such as inspection, examination, and evaluation used in conjunction with Non-destructive be translated into the word "non-destructive testing". Try to avoid writing "non-destructive flaw detection", "non-destructive inspection", "non-destructive testing", "non-destructive evaluation", etc. This translation method also applies to the translation of the names of various non-destructive testing methods.

Note: Words such as inspection, examination, and evaluation are only recommended to be translated into the word "testing" when translating the names of non-destructive testing and its methods. In other cases, it is advisable to translate according to the original content and Chinese habits.

English and abbreviations of commonly used NDT

methods: ultrasonic testing — UT
magnetic particle testing — MT
computed tomographic testing — CT
visual testing — VT
radiographic testing — RT
penetrant testing — PT
acoustic emission testing — AT, AE
eddy current testing — ET
leak testing — LT (end)