Remote Handling Systems

An energy-generating fusion reactor will need efficient methods for periodic maintenance and inspection of neutron-irradiated components. The importance of Reliability, Availability, Maintainability, and Inspectability (RAMI) has been recognized in the CPP/FESAC reports in order to be able to construct and operate a fusion nuclear facility like the Fusion Pilot Plant.

Research in this area is required to begin the development process towards actual large-scale remote inspection and maintenance mockups as the design matures and moves closer to the facility operation.

The fusion environment is very harsh, involving severe plasma, neutron, and gamma-ray loading all components in the fusion core during operation. When the plasma is off, the only remaining load is gamma radiation, which can be quite high in the first wall at ~ 5 x 105 Sv/hr (compared to allowed exposures of 20 mSv/yr for workers and 1 mSv/yr for the public) and will decrease to ~ 8 x 104 Sv/hr after 1 day to 1 week. The corresponding first wall decay heat begins at 4 x 105 W/m3 which drops to ~ 104 W/m3 after a similar amount of time. Inspection, diagnostic, maintenance, and transport equipment must be capable of performing their functions in these environments, and strategies for performing these functions must be developed. All operations must be robotically or remotely executed since the dose levels are far above the level allowed for human contact.

The remote maintenance challenge can be broken into a series of topics: materials and measurements development, tritium contamination control, advanced maintenance development, design activity to provide critical data for remote maintenance, and design strategies for enhanced maintainability and availability.