Mold Oscillating System with Optimized Non-Sinusoidal Oscillation Profile

Resumo

A mold oscillating system for continuous casting machines has been developed based on a nonsinusoidal oscillation profile with an online oscillation control capability. A new type of the mold oscillating system is proposed comprising two servomotor-driven eccentric shafts. The principle of operation of a non-sinusoidal oscillation system is described. Based on the analysis of the non-sinusoidal oscillation waveform expressed as a piecewise linear function, the angular speed of a servomotor necessary to realize such oscillations was determined. A procedure for calculating process parameters was developed. The model of synchronized control of the casting speed and oscillation frequency was optimized and process parameters were calculated for the deviation factor of 20% and amplitude equal to 4 mm. The mold oscillating systems of sinusoidal and non-sinusoidal type were compared. The advantages of the non-sinusoidal type of oscillating system were shown, which include a decrease in depth of the oscillation marks on the surface of continuous-cast billet, an improvement in the mold-ingot lubrication conditions, and higher quality of continuous-cast billets.