Speaker
Shijun Qin
(Tokamak Design Division)
Description
A preliminary RAMI (reliability, availability, maintainability and inspectability) assessment for the EAST in-vessel components cooling system based on currently available design is presented. The following sub-systems were considered in the analysis: the EAST PFCs heat-sink cooling system, two water pumps system, cooling loop including cycle feed pipe and cycle return pipe lines, secondary cooling equipment and pressure control system (PCS). EAST in-vessel components cooling system criticality chart was taken into discussion through Failure Mode, Effects & Criticality Analysis (FMECA), the criterion and program based on the ITER organization defined criticality, occurrence and severity rating scale. The reliability block diagrams (RBD) models were implemented taking into account: system reliability-wise configuration, operating schedule currently foreseen on the EAST experiment planning, maintenance schedule and plant evolution schedule as well as failure and corrective maintenance models. A simulation of plant activity was then performed on implemented RBDs to estimate plant availability performance on a mission time of 20 calendar years. The resulting availability performance was finally compared to availability goals previously proposed for DEMO plant by a panel of experts, also compared to the ITER divertor availability goals. The study suggests that inherent availability goals proposed for EAST in-vessel components cooling system are potentially achievable; the most critical failure modes of cooling system were highlighted during EAST operation, at the same time the mitigation actions for major risk were recommended. A sensitivity analysis is also presented to explore results dependency on key estimated parameters and analysis assumptions.
Co-authors
Damao Yao
(Tokamak Design Division, Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, China)
Jing Wei
(Tokamak Design Division, Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, China)
Kun Lu
(Tokamak Design Division, Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, China)
Shijun Qin
(Tokamak Design Division, Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, China)
Tiejun Xu
(Tokamak Design Division, Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, China)
Yuntao Song
(Tokamak Design Division, Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, China)
