METHOD OF PRODUCING CONTINUOUSLY CAST PIECES OF STEEL

摘要

A method of producing continuously cast pieces of steel, using a method of measuring the solidified state of continuously cast pieces by means of a sensor placed out of contact with the cast piece, comprising the steps of measuring the solidified state of the cast piece along the casting direction, detecting the position of the crater end from the measured solidified state, and controlling at least one condition selected from the conditions consisting of casting speed and secondary cooling water quantity on the basis of the position of the detected crater end, wherein the method of measuring the solidified state of the cast piece comprises the steps of cooling the cast piece until the surface layer undergoes a-transformation, transmitting the transverse waves in electromagnetic ultrasonic waves to the cooled cast piece, receiving the signal after it has penetrated the cast piece, and determining the solidified state on the basis of the received signal.