In-Line Induction Heat Treating of Tube, Pipe, and Bar Products

Requirements for greater product flexibility in the heat treating industry, driven by lean strategies, have resulted in growing global capacity for induction heating operations as well as the re-examination of processes to save production time and line space.  However, there are important considerations to keep in mind when developing and modifying heat treat recipes whether for full-body, full-length heat treating, or seam normalizing applications.  These include consideration of specialty alloy requirements and the presence of micro-alloying elements, the prior microstructure and presence of heavily banded structures, heating and cooling rates, and phase transformation kinetics especially with overheating and undercooling situations.  This paper focuses on the intersection of theory and practical application for induction heating operations.  Particular attention is paid to induction heating principles and fundamentals as well as new and proven methods for recipe generation.