| 摘要 |
PURPOSE:To obtain a ultrasonic flaw detector which can make ultrasonic waves incident to an entire steel pipe surface even if carrying speed of the pipe is changed. CONSTITUTION:A supersonic flaw detector comprises a carrying speed measuring circuit 21 for measuring carrying speed of a steel pipe 1 from a signal of a pulse generator 4, a carrying speed controller 20 for controlling speed of a carrying roller 2, a circuit 22 for calculating number of rotations and flaw detecting water amount which calculates the number of rotations of a rotating mechanism 8 from the carrying speed and ultrasonic beam width of a probe 7 to indicate the carrying speed and the number of rotations, and a flaw detecting water control circuit 25 for varying an amount of the flaw detecting water according to the number of rotations. The number of rotations is controlled following a change in carrying speed of the steel pipe 1 and the amount of flaw detecting water is varied according to the number of rotations. |
