| 摘要 |
PURPOSE:To set up accurately the standard of a transducer and perform accurate detection of obstacles, etc. by providing standard reflectors on the side face of the center of a reactor that stands opposite to a transducer and on the side face of the reactor center and providing a constitution in which ultrasonic waves that cut through the center of the reactor transversely are positively reflected. CONSTITUTION:A transducer (TR) 9 of an inside seeing-through device 6 of the nuclear reactor vessel 1 of a fast breeder reactor of liquid metal cooling type is placed opposite to a standard reflector 14 that is mounted on the upper mechanism 4 at the center of the reactor and sends ultrasonic waves. The TR9 is rotated in horizontal and up-and-down directions by means of a driving section 8 while receiving the reflected waves by the TR9 to obtain signal in refereence to the horizontal and vertical reference planes 14a and 14b for each reference positioning to the upper mechanism 4 at the center of the reactor. Next, exact detection of obstacles is made by sending ultrasonic waves to a reflector 11 through the gap 10. |
