Operational in-service inspection components

In-service infection of the tank. In-service inspection of the LMFBR tank system will be necessary in all future commercial size LMFBRs. By way of example one design solution is described here the MIR system for SUPERPHENIX. In SUPERPHENIX, in-service inspection of the reactor tank will take place during planned outages. The temperature condition will then be 180°C at the main pool tank and 130 C at the outer safety tank The space between the tanks is filled with nitrogen. The tanks hang from the slab which has 12 man-holes of oval shape (0.7 X 0.44 m) through which the in-service inspection vehicle MIR (Machine d Inspections pour Reacteurs rapides) can be inserted. The distance between the tanks will be some 600 mm at hot temperature conditions. The MIR system (Fig. 6.23) includes  

TV cameras for weld examination, guidance of the vehicle in the space between the tanks and for general viewing of the environment, 

The winch continuously controls and minimizes the traction force and torque exerted on the vehicle by the cable. It is located about 6 m above the upper part of the slab. In the event of emergency it can extract the vehicle from the space between the tanks. Control of the MIR system is achieved by a hierarchical computer system. A microprocessor carries out elementary orders and checks. 

Under-sodium viewing systems have been developed mainly in the USA (FFTF), in France (PHENIX, SUPERPHEMX) and in the UK (as described above in section 6.3). 

In-argon television and periscope inspection methods. Remotely operated TV camera systems have been developed for continuous TV viewing and with the ability to provide high resolution photographs. They were applied to inspect the core of PFR. Miniature cameras have also been developed to inspect the superheater tubes in PFR fi om the outside and evaporator tubes from the inside. Periscopes and horoscopes were extensively used in RAPSODIE, PHENIX and SUPERPHENIX. Good image resolutions were obtained at temperatures up to 150 C during inspection of different components. 

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