NUCLEAR-POWER-PLANT REFRESH TECHNOLOGY

Japan has fifty nuclear power plants in operation and some of them has been operated more than twenty five years. It becomes more important to develop maintenance technologies to prevent unscheduled outage. We have developed wet shot peening system to change tensile stress to com pressive stress around the weld preventing stress corrosion cracking ( SCC). Together with the stress improvement technology, we have develop ed multipurpose remote handling equipment to execute the tasks require d in a core area and an annulus area.