Study of gas pipelines corrosion using gamma-ray scattering beam

Resumo

The great part of the production of natural gas is transported through gas pipelines, which need periodic inspections to assess the structural integrity of the pipelines, due to possible defects caused by degradation, which can rupture causing leakage of the fluid causing major disasters. Based on this, this work presents a methodology for detecting corrosion in gas pipelines. The approach is based on the study of the spreading of gamma rays in order to investigate possible flaws in the ducts. For this, the diameter, thickness and composition of the pipeline and natural gas material were specified, as well as the internal operating pressure of the pipeline. In this study, the MCNPX code is used to perform the simulations, to develop a more appropriate counting geometry. The detection system uses a ¹³⁷Cs (662 keV) gamma-ray source and 2×2" NaI(Tl) detector to obtain scattered beam. Using this proposed geometry, it was possible to determine thickness loss of 0.5 mm that occurred by internal corrosion and 8 mm of width, and the material loss being 0.8 cm³ of carbon steel.