Abstract:The particle transport process and the degree of energy attenuation are different when the particle flow released by the decay of the radioactive source crosses the shielding materials of different thickness. Making use of this feature, a method that measures β particle’s energy deposition caused by internal β radioactive source at outer side of the pipeline was proposed to realize online nondestructive corrosion detection for aerial metallic oil and gas pipeline. The differences and characteristics of photon, electron flux and their energy distribution when β particles passed through steel shielding materials of different thickness were analyzed. After β radioactive source was devoted into the pipeline, the transport results of β particles generated by the decay which penetrate the metallic pipeline walls with normal and different corrosive degrees and eventually enter the NaI particle detectors were tested. Variance analysis was carried out to compare whether the thickness or area was more sensitive to this method. The results show that the ray detection method has strong sensitivity to the detection of corrosion thickness. This method can effectively detect corrosion damage with thickness exceeding 40% of the wall thickness of the pipeline.