Abstract: In production practice, some continuous casters, for which the molds undergo non-sinusoidal oscillation, suffer from severe resonance during their starting although the running frequency is much lower than the natural frequency of the oscillation system. The resonance can cause mold level fluctuation and even breakout. To get an insight view of this problem, the dynamic model of the oscillation mechanism is built up. The vibration excitation is deduced. Harmonic analysis is applied on non-sinusoidal excitation. The method to determine resonance interval is given. Factors concern the harmonic components are analyzed. Harmonic resonance analysis is carried on a practical oscillation system adopted by a certain iron plant. Also, a test to check the motion states of the mold is done. The test data support the theoretical results very well, which explains why the mold reciprocation table vibrates heavily in lateral direction. And harmonic resonance is verified. Harmonic resonance has general sense in non-sinusoidal oscillation of the mold. So harmonic resonance should be analyzed if only the mold under-goes non-sinusoidal oscillation.

Key words: Continuous casting, Harmonic resonance, Mold oscillation system, Nonsinusoidal oscillation, Resonance harmonic, Resonance interval