The non-destructive testing of the elbow is to ensure that there are no defects and damage inside the elbow to ensure its safety and reliability. Common nondestructive testing methods include ultrasonic testing, magnetic particle testing, eddy current testing and X-ray testing. The following is the interpretation of these non-destructive Testing methods and related standards: Ultrasonic Testing (UT) : Ultrasonic testing is the use of ultrasonic waves in the material propagation characteristics for defect detection and evaluation. The ultrasonic wave is transmitted to the detected object through the probe, and the defect or damage is judged according to the strength, time and shape of the detected echo signal. Commonly used Ultrasonic Testing standards include GB/T 2970 “Ultrasonic Testing of Metal Materials” and ASTM E213 “Standard Practice for Ultrasonic Testing of Metal Pipe and Tubing”. Magnetic Particle Testing (MT) : Magnetic particle testing is the use of magnetic field under the action of the defect surface magnetic change principle for detection. By coating magnetic powder on the surface of the detected object and observing the aggregation of magnetic powder after applying a magnetic field, it can be determined whether there is a phenomenon of magnetic particles adsorbing on the defect surface. Commonly used Magnetic Particle Testing standards include GB/T 9444 “Magnetic Particle Testing Technology” and ASTM E709 “Standard Guide for Magnetic Particle Testing”. Eddy Current Testing (ET) : Eddy current testing is the use of eddy current induction principle for defect detection. The eddy current formed by conducting alternating current on the surface of the detected object is observed to determine whether there is defect or damage. Commonly used Eddy Current Testing Standards include GB/T 7735 “Eddy Current Testing Technology” and ASTM Eddy Current Testing Standards. Radiographic Testing (RT) : Radiographic testing is the use of rays in the material transmission and scattering principle for defect detection. By passing the ray through the object to be detected, the image of the internal defect or damage of the material is observed on the film or electronic developer to determine its presence and extent. Common Radiographic testing standards include GB/T 7233 Terms for Nondestructive Detection of Industrial Radiation and ASTM E94 Standard Guide for Radiographic Examination. The above is the interpretation of some common nondestructive testing methods and related standards, and the specific choice of methods and standards should be combined with the characteristics, needs and scope of application of the actual test object to make decisions. At the same time, the process of non-destructive testing also needs to be carefully operated and strictly abide by the relevant safety operating procedures to ensure that accurate and reliable test results can be obtained.
