INSPECTION APPARATUS FOR PRESSURE VESSEL IN ATOMIC REACTOR

摘要

PURPOSE:To facilitate the inspection by providing an anti-swing mechanism at the forward end of a mast thereby preventing the mast from swinging at the forward end thereof. CONSTITUTION:An anti-swing mechanism 27 is provided at the forward end of a lower mast 21 and a fixed support 28 is guided along the inner surface at the drum part 1 of pressure vessel for reactor with a wheel 29 being fixed to the support 28 at the forward end thereof. A movable support 30 comprises an air cylinder 31, a pin 33, and a wheel 32 which is pressed against a shroud 7 with the pin 33 as a fulcrum. Since the mast 21 is secured by means of a mechanism 27 comprising the supports 28, 30, the mast 21 is prevented from swinging and the welding line can be inspected accurately. A pin 37 and an air cylinder 35 for supporting the lower arm 24 on a lower arm support 36 constitute a swinging mechanism 34 and the arm 24 is swung to the left and right through telescopic motion of the cylinder 35 and an ultrasonic probe 23 is fixed to the forward end of the arm 24. This structure facilitates scanning of the probe 23 in the axial and circumferential direction along the inner surface at the drum part 1.