As an important part of oil and gas pipelines, the quality and safety of bend pipes affect the safe operation of pipelines. In this paper, a case of a bending pipe leakage accident was tested and analyzed. Through non-destructive testing, physical and chemical property inspection, and defect anatomy analysis, it was found that the bending section of the bending pipe did not meet the standard requirements and the material was hard and brittle. It is concluded that the leakage of the bend pipe belongs to low-stress brittle failure. The main reasons for the failure of the bend pipe are improper material selection and unreasonable heating process, a hard and brittle martensitic structure formed in the bending section, deformation, and reduced bearing capacity.
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