A finite element model for the temperature filed simulation on the local induction heating of thick A335P92 steel pipe was built using ANSYS software. The sequential coupling of magnetic field and the temperature field was considered. An automatic thermal tracing program was developed, and the induction heating temperature field was simulated, then the temperature difference between the inner and outer walls are investigated. After model verification, the effects of heating width, number of coils/ coil gap, frequency, coefficient of heat transfer on the temperature field were analyzed. The results show that the skin effect is significant during the local induction heating and the temperature fluctuation occurs at the curie-point temperature; the heating width over 600 mm, the number of coils (n=10-30) and the electromagnetic frequency (H=1000-3000 Hz) have little effect on the temperature difference between the outer wall and the inner wall; the coefficient of heat transfer on the inner wall play a key role on the temperature difference between the outer wall and the inner wall.
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