| 摘要 |
PURPOSE:To detect the position of a weld zone automatically and to permit inspection of the defects therein by providing a traveling car, weld zone detector, ultrasonic probe, traversing mechanism, etc. CONSTITUTION:A flaw detector 20 is first attracted to a piping 1 by the magnetic force of the traveling car 21, then the car 21 is driven to move in the axial direction of the pipe. The weld zone detector 22 detects the position of the weld zone A and after an ultrasonic probe 23 arrives above the weld zone A, respective traveling wheels 28 of the car 21 are rotated backward by which the car is changed in the direction 90 deg. at this place. The probe 23 is lowered by a lifting mechanism 25 after the direction change and is brought near to the weld zone A apart at about 1-2mm spacing. Detection of the defects is executed by moving the probe 23 back and forth laterally by the traversing mechanism 24 while running the car 21. The probe 23 is turned around the piping 1 along the weld zone A in such a manner and is risen upon ending of the inspection. The respective wheels 28 are rotated backward and are changed in the direction 90 deg. at this place. The car 21 is directed toward the axial direction of the pipe after the direction change; thereafter, the car moves again while the weld zone A is kept detected. |
