Patent ID: 7740051
Filing Date: 2010-06-22
Classification: B22D,G01N

Abstract:
1. A method for detecting a crater end of a continuously cast product, the method comprising the steps of installing an ultrasonic shear wave sensor for transmitting an ultrasonic shear wave to the continuously cast product and receiving the transmitted ultrasonic shear wave and an ultrasonic longitudinal wave sensor for transmitting an ultrasonic longitudinal wave to the continuously cast product and receiving the transmitted ultrasonic longitudinal wave at the same position in a continuous casting machine or at positions apart from each other in a casting direction, but at the same position in a transverse direction of the cast product, detecting based on variations of an ultrasonic signal received by the ultrasonic shear wave sensor that the crater end of the cast product is matched with an installed position of the ultrasonic shear wave sensor, calibrating a calculation formula for determining the crater end from a propagation time of an ultrasonic longitudinal wave signal such that the crater end computed from the propagation time of the ultrasonic longitudinal wave signal at that time is matched with the installed position of the ultrasonic shear wave sensor, and after the calibration, determining the crater end from the propagation time of the ultrasonic longitudinal wave signal based on the calibrated calculation formula.