Research on defect depth measurement algorithm in Digital Radiography Testing

The defect depth had always been difficult to measure in the regular Radiographic Testing in the past, but can be accurately measured in Digital Radiographic image grayscale by the digital image processing technology. In the paper, the corresponding relation between the digital image grayscale value of the welding defect and the X-ray strength, was analyzed by means of Beer Theorem, and an algorithm for accurate weld defect depth was put forward. The algorithm was verified by comparing with the experimental data by means of the experimental platform and the simulation software. The result shows that the algorithm error range does not exceed ± 5% of the measured value.