ITER Test Blanket Module—Engineering Investigations for Port Cell Pipe Forest Replacement

Abstract

The ITER Test Blanket Modules (TBMs) are installed and operated inside the vacuum vessel (VV) at the equatorial ports located within port plugs (PP), and each of them includes two TBMs. After each plasma operation campaign, the TBM research plan testing program requires the replacement of the TBMs by new ones during the ITER long-term shutdown (LTM). The replacement of a TBM requires the removal/reinstallation of all test blanket system (TBS) equipment present in the port cell (PC), including those in the port interspace called pipe forest (PF). The TBS equipment in PC shall be designed so that occupational radiation exposure can be as low as reasonably achievable (ALARA) over the life of the plant to follow the ITER Policy. To implement ALARA process requirements, a design shall consider careful integration assessment since early phase to address all engineering aspects of the replacement sequence. The design of the TBS equipment in PC shall optimize the reconfiguration operation by including human factor considerations and providing adequate space. Provisions for dose reduction measures (DRMs) considering protection means and minimization of occupancy times in radiation fields are also investigated by assessing remote technics to reduce operator exposure. This article describes engineering investigations for optimized PF replacement operations in various engineering fields. Results on the design of the TBS equipment in the TBM-PC are discussed. The PF design shall implement nuclear engineering aspects. Design options shall demonstrate constructability and maintainability meaning compliance with ALARA process and adequate construction codes (RCC-MRx, EN 13480). TBM-PP replacement sequence drives several elements of the TBM-PC component design and associated integration. Concepts are discussed with regard to nuclear engineering and operation aspects. Use of prototyping demo, including virtual reality (VR), will support the preliminary validation during the system engineering process in order to prepare the full-scale mock-up validation phase.