Abstract Radioactive Waste(RW) Tanks are periodically inspected and repaired to maintain the high reliability in operational n uclear power plants. On the other hand, these works have been desired to perform by not human power but using remote-controlled equipment for the purpose of radiation exposure dose reduction for workers. To meet these requirements, the authors had been dev eloped the inspection robot and YAG-laser repair-welding robot, both of which were remote-controlled in underwater environment....
英字タイトル:
Development of underwater robot system for surface inspection and repair welding

The possibility of simultaneously nondestructive evaluation for material deterioration and detecting sub-mm sized small defect were investigated using magnetic methods. The magnetic hysteresis properties and the distributions of leakage magnetic field were measured by a magnetic yoke and a magnetic field sensor. The hysteresis loop measurement was sensitive to deterioration in material and scanning flux distribution was effective for detection of sub-mm sized defect. The deterioration and small defect ...
英字タイトル:
Simultaneously nondestructive evaluation of degradation and defect in sub-mm size using magnetic sensing techniques

NDE techniques using magnetic methods such as hysteresis loop, Barkhausen noise, magnetoacoustic emission, permeability changes are used for characterization of ferromagnetic steels and eva luation of degradation of steels. Also, magnetic flux leakage testing is used for wall thinning on the tubes in various plants. In this paper, a feasibility of those magnetic techniques for applying evaluation of small defects with sub-mm size was examined. As the results, the techniques except MFL method have no abilit...
英字タイトル:
NDE for defects with sub-mm size using magnetic techniques