Reliability based assessment of remote maintenance system for CFETR divertor

China Fusion Engineering Testing Reactor (CFETR) will be built to test and verify the feasibility of engineering and technology in practice for the future fusion reactor. Long pulse and steady-state operation will be demonstrated with duty cycle time not less than 30˜50%. Because of the beta and gamma activation of the component bulk and surface dust, special remote handling techniques will be required during machine maintenance periods. The divertor cassettes remote replacement is one of the key maintenance operations for the CFETR to meet the duty cycle time requirements. RH maintenance strategies will have a significant impact on the layout of the machine and design of components. Overview of the different CFETR divertor components remote maintenance strategies as well as to describe the maintenance process of the in vessel components will be discussed. Preliminary reliability assessment of the divertor maintenance system was done in order to carry out RH maintenance tasks safely and efficiently.