A study on the failure of AISI 304 stainless steel tubes in a gas heater unit

Abbas Bahrami, Peyman Taheri

    Research output: Contribution to journalArticleScientificpeer-review

    22 Citations (Scopus)
    119 Downloads (Pure)


    This paper investigates a failure in convection section tubes of a gas heater unit in a petrochemical plant. Tubes are made of AISI 304 stainless steel. The failure is reported after 5 years of service at working temperature 500 °C. The failure is in the form of circumferential cracks in the vicinity of the weld. Various characterization techniques, including optical and electron microscopes as well as energy-dispersive X-ray spectroscopy (EDS), were used to study the failure. Results showed that that the damage has initiated in the heat affected zone (HAZ) area parallel to the weld/base metal interface. Cracks have propagated alongside grain boundaries, resulting in an intergranular fracture. The main cause of failure was concluded to be attributable to the grain boundary sensitization and intergranular grain boundary attack due to improper welding and long time exposure of tubes to high temperature. Possible mitigation strategies to minimize similar failures will be discussed.
    Original languageEnglish
    Article number969
    Number of pages7
    Issue number9
    Publication statusPublished - 2019


    • convection tubes
    • AISI 304 stainless steel
    • failure analysis
    • sensitization


    Dive into the research topics of 'A study on the failure of AISI 304 stainless steel tubes in a gas heater unit'. Together they form a unique fingerprint.

    Cite this