What are the detection methods for oil casing

1. Ultrasonic detection: When ultrasonic waves are propagated in the material being tested, the acoustic characteristics of the material and the changes in the internal structure have a certain impact on the propagation of ultrasonic waves. By detecting the degree and situation of the influence of ultrasonic waves, the changes in the function and structure of the material can be understood.

2. Radiographic detection: Radiographic detection uses the difference in the amount of radiation transmitted between the normal part and the defect to form the discrimination of the blackness on the film.

3. Penetrant detection: Penetrant detection uses the capillary action of the liquid to penetrate the open defect on the surface of the solid material, and then absorbs the penetrated penetrant to the surface through the developer to show the existence of the defect. Penetrant detection is suitable for various metal and ceramic workpieces, and the time from penetration operation to defect appearance is relatively short, usually about half an hour. It can detect surface fatigue, stress corrosion, and welding cracks, and can directly measure the size of the cracks.

4. Magnetic particle testing: Magnetic particle testing uses the leakage of the magnetic field at the defect to absorb magnetic particles and form magnetic traces to provide defect visualization. It can detect surface and sub-surface defects. The nature of the defects is easy to distinguish. Paint and electroplated surfaces will not affect the detection accuracy.