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The first ITER toroidal field coil structures (TFCS) have been successfully completed by the Japan Domestic Agency with the solving of major technical challenges, and further fabrication is ongoing. There were five major challenges for the TFCS fabrication. This paper describes these challenges and the solutions established during fabrication and how to implement to the ITER TFCS.

This report summarizes the evaluation method, the development schedule and the result of the test. A conceptual design study of the Japanese sodium-cooled fast reactor (JSFR) is in progress of “Feasibility Study on Commercialized Fast Reactor Cycle Systems.” In this study we have proposed a component which integrated IHX (Intermediate heat exchanger) with primary pump into one vessel (integrated IHX/Pump) as one of advanced concepts for the plant economy. By development this component, the amount of material (steel) of the primary cooling system can be reduced and the maintenance performance of IHX can be improved. In order to confirm its feasibility, it is important to avoid the resonant vibration caused by integrating of the pump into the static IHX and to prevent excessive wear-out of the heat exchange tubes caused by contact with the tube support plates. Therefore, the vibration evaluation method has been developed and a lot of examinations were carried out to confirm the feasibility of this concept. The pump is arranged at the center of the IHX and heat exchange tubes are arranged concentrically. This component consists of the multiple cylindrical layers. Tube support plates are installed and they support the tube bundle with 0.1–0.3mm gaps. The 1/4-scale model was selected for vibration tests. The first step test with an internal vibration exciter which simulated the pump was performed, and the test with the pump installed into IHX was done. This test model has been installed at Takasago R&D center of Mitsubishi Heavy Industries, Ltd. The vibration caused by the pump was measured. As a result of data analysis, the character of frequency response was acquired. The analysis code called as “FINAS” can directly handle the vibration behavior of complex multi-cylinders with fluid between the cylinders. The eigenvalue analysis and response analysis were performed using a detailed model and the results were compared with the test results. Vibration evaluation methods of the integrated IHX/Pump have been studied. The 1/4-scale vibration test was performed and the results were compared with the analysis.

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