Failure Analysis of a Welded 316L Stainless-Steel Stack with Premature Damage Due to Stress-Corrosion Cracking

• Published in: Journal of failure analysis and prevention 2024-12, Vol.24 (6), p.2683-2699
• Main Authors: León-Henao, H., Morales-Galeano, J. E., Santa-Marín, J. F., Giraldo-Barrada, J. E.
• Format: Article
• Language: English
• Subjects: Austenitic stainless steels; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Corrosion and Coatings; Corrosion mechanisms; Corrosion tests; Dew point; Emission analysis; Failure analysis; Leak testing; Materials Science; Optical emission spectroscopy; Original Research Article; Quality Control; Radiography; Reliability; Safety and Risk; Solid Mechanics; Spectrometry; Stress corrosion cracking; Sulfuric acid; Tribology; Visual observation; Welded joints
• ISSN: 1547-7029; 1864-1245
• DOI: 10.1007/s11668-024-01990-y

This study analyzed the premature failure of a stainless-steel stack obtained from a mining company. The stack was manufactured using ASTM A240 Type 316L stainless steel. After one year of its service, massive leakages and cracks were observed near the welds. Following a visual examination of the stack, a representative sample was extracted and analyzed using visual and radiographic inspection, metallographic examination, scanning electron microscopy, energy-dispersive spectrometry, optical emission spectrometry, ferrite number analysis, and leak testing. Furthermore, corrosion mechanisms and the sequence of events leading to failure were determined. Two different mechanisms were identified: acid dew point corrosion caused by the condensation of H 2 SO 4 and HCl at the inner walls of the chimney, followed by stress-corrosion cracking near the welded joints.