APPARATUS FOR DETECTING FLAW OF CYLINDER FLANGE PART OF PRESSURE VESSEL OF NUCLEAR REACTOR

摘要

PURPOSE: To detect a flaw in water by setting both carriages to a cylinder flange in a relatively movable fashion in a circumferential direction, holding and fixing a stud bolt at each clamp part, relatively moving the carriages when one clamp part is fred from the fixing, and detecting a flaw at a flange surface when the clamp part is fixed. CONSTITUTION: A lower and an upper carriages 11, 12 are set to be relatively movable in a circumferential direction of a cylinder flange 3. Clamp parts 13 are attached at both sides of each carriage 11, 12, to hold stud bolts 10 to selectively fix the carriages 11, 12. When the carriages 11, 12 are not at an inspecting position, a running part 14 is driven to correct the position. First, the carriage 11 is fixed and the carriage 12 is let to run. Then, the carriage 12 is fixed, while the carriage 11 is released to run, so that, the carriages 11, 12 are brought into a state overlapping up and down. Thereafter, the carriages 11, 12 are fixed, a probe module of a flaw-detecting part set to the carriage 11 is sent in touch with a surface of the flange, thereby carrying out a flaw detection. In this manner, a necessary point can be subjected to a flaw detection even in water.