Reliability, Availability, Maintainability and Inspectability (RAMI) Analysis Supporting the Design of ITER Ancillary Systems for Tritium Breeding

The ITER research facility is an excellent example of a complex system, requiring a structured analysis of its Reliability, Availability, Maintainability and Inspectability (RAMI) performance. In particular, this paper is focused on the Water Cooled Lithium-Lead Tritium Breeding Module (WCLL-TBM), which is one of the systems under development for the self-breeding of tritium to be tested in ITER. The reliability and availability targets of ITER shall be achieved also considering the failures of the WCLL-TBM components. Moreover, the reliability and availability of the WCLL-TBM shall be evaluated with reference to its capability to carry out the required main function, which is to demonstrate and test the breeding of tritium. This paper describes the process followed for the RAMI analysis of the WCLL-TBM Ancillary systems, highlighting the compelling need for parallelism and iterations with the design activities and with the specification of the maintenance strategy, and providing an overview of the key design aspects, of the main difficulties and challenges encountered, and of the improvements achieved.