Comparison between radiographic inspection and ultrasonic testing
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I would like to ask what are the differences between RT and UT? Things like convenience, cost, and accuracy. The drawings used in our company are all in RT format; the plate thicknesses are probably no more than 30, and we have never used ultrasound technology
The main difference is the varying sensitivity to cracks
Each method has its advantages and disadvantages. Radiographic testing has a high detection rate for volume-type defects such as pores and inclusions, while ultrasonic testing is more sensitive to area-type defects such as cracks and lack of fusion. Ultrasonic testing requires a certain testing surface area, and it also has specific requirements regarding the curvature of the workpiece; it is highly dependent on technical skills. If cost is not a concern, it is recommended to use both radiographic and ultrasonic testing methods.
Ultrasonic waves are relatively efficient, radiation-free, and inexpensive.
Key difference: X-rays can determine the nature of defects (through imaging), while ultrasound can only make a relative comparison to the existing defects in a reference block in order to assess the equivalent severity of the defects
By looking at the following content, it can be understood basically: NBT 47013-2015.1 \"Non-destructive testing of pressure equipment – Part 1: General requirements\" 5 Principles for the use of various non-destructive testing methods 5.1 General principles 5.2 Scope of capability and limitations of each non-destructive testing method
I’m not very familiar with design and manufacturing; let’s talk about regular inspections instead. Those with too small a thickness (usually less than 6) cannot be examined using ultrasound; only radiography is possible. X-rays can clearly detect defects such as porosity and slag inclusions, while ultrasound is more sensitive to layers, cracks, etc. Ultrasound does not emit radiation and is easy to use. However, it requires higher standards for personnel; the same defect may produce different results when handled by different people, whereas radiation inspection is more straightforward. Generally, due to people’s fear of radiation and their love for life, those who are capable of performing ultrasound procedures avoid using radiation. Manufacturing inspection is different from periodic inspection.
Ray inspection is sensitive to volume defects, while ultrasonic inspection is sensitive to surface defects. Additionally, if the thickness of the part to be inspected is too great, conventional X-ray machines may not be sufficient; in such cases, recordable ultrasonic testing methods such as TOFD are used. Oh, I vaguely remember that special materials are given priority for radiographic inspection.