| 摘要 |
PURPOSE:To decrease the change in sensitivity in a flaw detecting range and to widen the flaw detecting range by setting probes in parallel at a prescribed distance from the surface of a square billet and electronically and linearly scanning the probes thereby detecting the flaw of the billet. CONSTITUTION:Three pieces of probes 1 in the same position with respect to the axial direction of, for example, a square billet 2 are disposed respectively in parallel with the three surfaces of th billet 2 in this flaw detecting method. The ultranosnic beam S transmitted from the probe 1 positioned in the middle among these probes is received by both probes 1 positioned on both sides. Even if there is a defect 12 inclined largely with respect to the surface in the inside of the billet 2, the defect 12 can be easily detected. More specifically, the change in the sensitivity in the flaw detecting range is decreased and the flaw detecting range is widened according to the above-mentioned method. |
