In this paper, a failure analysis was performed on a high-pressure steam pipeline, which was burst after service in a chemical plant for 12 years. The burst field was investigated and the fragments were observed. Microstructures of the pipeline were analyzed by optical microscope (OM) and scanning electron microscope (SEM). The mechanical properties tests, including tensile testing and Charpy V notch impact testing, were performed on specimens removed from the high-pressure steam pipeline. The impact testing results showed that toughness of the material was poor and little resistance against cracking extension. According to further analysis, strain aging was the dominant mechanism of the failure. Some inspection approaches were recommended to prevent similar failures.
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