Failure Analysis of Radiant Tube Burners in Continuous Annealing Line (CAL) of an Integrated Steel Plant

Journal of Failure Analysis and Prevention 01/2011; 11(3):286-292. DOI: 10.1007/s11668-010-9426-8

ABSTRACT Failure analysis of radiant tube burners (ACI HK 40 with composition ~25wt.% Cr, ~20wt.% Ni) removed from a continuous annealing
line (CAL) of a cold rolling mill (CRM) of an integrated steel plant was performed using optical microscopy (OM), scanning
electron microscopy (SEM), electron probe microanalysis (EPMA), and microhardness measurements. Studies revealed that the
failures were mainly attributed to combined influences of creep and carburization-assisted localized oxidative attack. A suitable
heat-resisting cast austenitic stainless steel was identified as a candidate alloy to replace the previously used ACI HK 40

KeywordsCast austenitic stainless steel–Radiant tube–CAL–CRM

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May 23, 2014