Failure analysis of a natural gas pipeline

In the present work, the failure investigation of a 30 in. diameter gas transmission pipeline (API 5L X-60 grade steel) has been described. The failure was due to a longitudinal crack developing in the centerline of longitudinal weld joint. Mechanisms and morphology of crack initiation and propagation were studied through different tests including: thickness measurement, chemical composition analysis, metallographic inspection, mechanical property testing, and scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS). The experiments resulted in the conclusion that some factors associated with Sulphide Stress Cracking (SSC) and metallurgical defects cause the failure of welded joint pipe. Detailed examination revealed that these factors are inappropriate welding parameters, pitting corrosion on longitudinal weld, and hydrogen permeation to the weld metal.

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  • English

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  • Accession Number: 01677973
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Aug 1 2018 4:52PM