| 摘要 |
PURPOSE:To enable accurate detection of an internally ground shape of a weld part of a seam welded pipe by arranging a pair of linear array probes sandwiching a welding line to perform an overlap processing of position information measured with an alternate switching thereof. CONSTITUTION:A pair of linear array probes 3 and 4 are arranged along the circumferential direction of the seam welded pipe 1 at positions as opposed to each other centered on a weld bead part 2 on the outside of the seam welded pipe 1. Transmitting and receiving sections 5 and 6 have a function of transmitting and receiving transmitting and receiving signals of the probes 3 and 4 and the transmission and reception thereof are controlled by mutual switching by a measurement control section 7. With the mutual switching by the measurement control section 7, one of vibrators of the probes 3 and 4 is scanned sequentially to emit an ultrasonic beam to an internal bead grinding section 2a at a certain emission angle and reflected wave is received with the other vibrator of the probes 3 and 4 to measure time between the emission and reception of the beam with a measurement control section 7 and a position of the receiving vibrator. These signals measured with the alternate switching undergo an overlap processing with an arithmetic section 8 to display 9 the results of the processing. |
