Why are interference fittings heated by power frequency induction heating instead of medium-high frequency heating? Below are some reasons given by Changzhou JunTai Machine Science and Technology Co., Ltd.:
The medium-high frequency heating is mainly used by the heat treatment industry. Its working principle is to use the skin effect theory to deal with the surface of workpieces. Regarding the interference assembly, it requires even heating of the internal part of the workpiece to make it expand quickly, which means that good permeability is necessary. Yet the penetration length of the power frequency is several times of that of high frequency. In addition, the assembled workpieces are finished products needing no secondary heat treatment. So medium-high frequency is more likely to make the temperature of the workpieces too high and hence results in skin annealing of the surface.