| 摘要 |
PURPOSE:To achieve a higher reliability in the evaluation of quality by performing a vertical flaw detection moving a probe and a material to be inspected relatively in a direction orthogonal to an array of vibrators to detect a distribution of detects so that an area measurement is made possible for defects of the material to be inspected. CONSTITUTION:A steel pipe 20 is transferred axially being turned about an axis center. In a transfer path of the steel pipe 20, a probe 1 made up of a number (n pieces) of small vibrators arranged axially is provided so as to contact the steel pipe 20 and the probe 20 detect flaws in the steel pipe 20 spirally with the rotation and transferring of the steel pipe 20. Then, the probe 1 is so set to perform a vertical flaw detection for the steel pipe 20. Thus, with one operation of detecting flaws, a flaw detection becomes effective for the steel pipe 20 in a range equivalent to an area of the vibrator. This operation is performed continuously in an axial way spirally to accomplish a flaw detection over the entire circumference and length of the steel pipe 20. This flaw detection operation enables the detection of a distribution of defects thereby determining an area of the defect from the distribution of the defects. |
