Five principles of conventional non-destructive testing---Principle of radiation detection,2018 hatatest ndt equipment

#Non-destructive testing technology does not destroy parts or materials, can be directly tested on site, and is highly efficient. At present, there are five main types of non-destructive testing: Ultrasonic Testing, Radiographic Testing, Magnetic Particle Testing, Penetrant Testing, and Eddy Testing. Current Testing).

There are many types of rays, and there are three types of X-rays, gamma rays, and neutron rays that are easy to penetrate. These three types of radiation are used for non-destructive testing, where X-rays and gamma rays are widely used for defect detection in boiler and pressure vessel welds and other industrial products and structural materials, while neutron rays are used only for special occasions. The most important application of ray inspection is to probe macroscopic geometric defects (inspection) inside the test piece. Radiation detection can be divided into a number of different methods depending on the characteristics, such as the type of radiation used, the equipment being recorded, the process and technical characteristics. Radiography refers to a non-destructive detection method in which a test piece is penetrated by X-rays or γ-rays and a film is used as a device for recording information. This method is the most basic and widely used method of radiation detection. Radiation testing is suitable for most materials and product forms, such as weldments, castings, composites, etc. The radiation detection film can produce a visual image of defects in the internal structure of the material, which is qualitative and quantitative, and the detection result is directly recorded, and can be stored for a long time. For volume-type defects, such as pores, slag, etc., the detection rate is very high. For area-type defects, such as cracks and final fusion, if the photographic angle is not appropriate, it is easier to miss the inspection. The limitation of radiation detection is also that the cost is high and the radiation is harmful to the human body.

Email : peng@hata-ndt.com

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