| 摘要 |
PURPOSE:To always make flaw detecting terminal follow a weld seamed part with high accuracy, by rotating a magnetic core in a detecting coil placed in the proximity of a steel pipe, detecting the seam jointed part, and controlling a rotation follow-up device in accordance with its signal. CONSTITUTION:A seam detector 1 and a flaw detecting terminal 2 are fixed to a fitting plate 4 connected to a rotation follow-up mechanism, and the follow-up mechanism is rotated around a welded steel pipe 3. In a detecting coil 13 of the detector 1, a magnetic core 14 is rotated concentrically. The flaw detecting terminal 2 is rotated and moved by detecting a peak point of a signal of the seam jointed part, which is generated 2 times by one rotation of said magnetic core 14 and controlling the rotating direction of a servo-motor 9 so as to make intervals of the peak point equal. In this way, the flaw detecting end 2 is always restored directly above the seam. |
