| 摘要 |
PROBLEM TO BE SOLVED: To detect a surface defect distinguishing it from a pipe end contact part. SOLUTION: In the pipe edge detection device of automatic flaw-detection line for automatically detecting the flaw of a steel pipe P being continuously carried while pipe ends are in contact with each other, at least two probe-type sensors 4a and 4b are provided at a position where the angle in steel pipe circumferential direction is changed are provided on the upstream side from the flaw-detecting machine, an AND circuit 9 is formed by the output of the probe-type sensors 4a and 4b, and a pipe end contact surface signal 10 is taken out by distinguishing it from a surface mark SD other than pipe end contact surfaces 6 and 7. |
