Main maintenance operations for Test Blanket Systems in ITER TBM port cells

•The Test Blanket System components layout in Port Cell room is described.•The maintenance of the two Test Blanket Systems in ITER port cell is addressed.•The overall replacement/maintenance strategy is defined.•The main maintenance tasks of the systems are discussed.•The maintenance strategy and required tools are presented. Each Test Blanket System in ITER is formed by an in-vessel component, the Test Blanket Module, and several associated ancillary systems (coolant and Tritium systems, instrumentation and control systems). The paper describes the overall replacement/maintenance strategy and the main maintenance tasks that have to be considered in the design of the systems. It shows that there are no critical issues.