APPARATUS FOR MEASURING THICKNESS OF SOLIDIFIED CAST PIECE

摘要

PURPOSE:To measure the thickness of a solidified cast piece highly accurately, by performing statistical processing of a received electromagnetic ultrasonic wave signal, and removing the signal having abnormal waveforms. CONSTITUTION:Based on the transmission pulse of an electromagnetic ultrasonic wave from a pulse generating circuit 8 and the received signal of the electromagnetic ultrasonic wave through a gate circuit 11, the transmitting time of the ultrasonic wave through a steel piece 7 is measured by a transmitting-time measuring circuit 12. The repeated measured values are stored in a memory part of the transmitting-time operating circuit 22. Whether the stored contents are effective or not is determined by the judged result from an abnormal waveform removing circuit 23 based on the comparison of the result of the statistical processing of the amplitude and the wavelength of the received signal from the gate circuit 11 and a preset value. The average value of the effective stored contents is applied to a solidified thickness operating circuit 15. The abnormal waveform signal generated by randum noises and the like is removed by the statistical processing. Thus the thickness of the solidified cast piece is measured highly accurately.