| 摘要 |
PURPOSE:To realize an inside-surface pitting detection device by which the pitting being formed on the inside surface of a boiler heat-transfer tube can be quantitatively and accurately evaluated. CONSTITUTION:In an inside-tube inserting type ultrasonic flaw detecting device, a plurality of oscillators 2 are linearly arranged at equal intervals so as to be opposite to each other in the direction of 180 degrees in the electronic scanning probe 3 being the detection part thereof. A supporting body 3' having two sets of the probes 3 is inserted into a heat-transfer tube 1 while being rotated, and vertical ultrasonic wave beams are transmitted by the probes 3, and the reflected echoes from the inside surface of the tube are received for measuring the path lengths A, B1, and B2 of the ultrasonic wave beams, and the depth 8 of the pitting of a pitting formed part 6 is quantitatively determined. |
