Metallurgical evaluation of a five inch cylindrical induction melter

Abstract

The metallurgical condition of a cylindrical induction melter (CIM) vessel was evaluated after approximately 375 h of operation over a two-year span at temperatures between 1400 to 1500 °C. Wall thinning and significant grain growth was observed in the lower portion of the conical section and the drain tube. No through-wall penetrations were found in the cylindrical and conical sections of the CIM vessel and only one leak site was identified in the drain tube. Failure of the drain tube was associated with localized over heating and creep. The observed degradation resulted from cumulative service at elevated temperature.^[1] A recommendation was made to implement a support for the conical section of the CIM and to increase the wall thickness of the drain tube. Thus, the possibility of drain tube misalignment in the induction coils and localized over heating will be minimized. In addition, the use of grain stabilized Pt/Rh alloy should be evaluated as a method to prevent grain growth.