摘要
The electromagnetic and temperature fields in the multistage intermediate-frequency induction heating of coated steel tubes were calculated using a numerical simulation.The influence of the voltage and frequency on the parameters of power circuit and heating temperature of the steel pipe was also analyzed.The results indicate that:(1) the electromagnetic field of induction heating is concentrated between the induction coil and steel tube and dissipated more at both ends of the coil;(2) during the induction heating,the temperature difference between the outer and inner walls of the steel pipe is approximately 3040 K,and the two temperatures rapidly tend to be the same after exiting the induction heater;(3)during the natural cooling,the temperature drop of the steel tube in the low-temperature section is approximately 10 K,and that in the high-temperature section is approximately 20 K;(4)the appropriate induction heating frequency and matching capacitance should be selected,so that the temperature of the steel pipe,especially at the outer wall,meets the coating process requirements,and as to achieve a synchronous improvement of the power efficiency and heating efficiency.This study is beneficial to building a more low-consumption and high-efficiency coating line of large-diameter steel pipes in Baosteel.
