Overview of sodium test facilities in Takasago R and D Center of Mitsubishi Heavy Industries, Ltd

Sodium test facilities were constructed and operated in MHI since 1975. MHI had several sodium test facilities, which were multi-purpose sodium testing facility (MTL-3, MTL-4), thermal transition test facility in Sodium (SASS), materials test facility in sodium, and thermal hydraulics test facility (SGTF). MHI have MTL-3, SASS and SGTF at present. MTL-3 was originally constructed in 1975. It was transferred to Takasago R and D center and fabricated in 1987. MTL-3 can simulate the concentration of oxygen and the temperature of the primary sodium loop. It is suitable for material tests or compatibility tests with sodium. The control temperature of its cold trap is 120 deg. C. The design temperature is 550 deg. C. Test pot in 0.7m dia. and 1.9m height has flexibility for various tests. SGTF was constructed in 1985 for heat transfer and thermal hydraulic test of steam generators. SGTF have two sodium systems, which are elevated temperature sodium system (800l/min) and low temperature sodium system (400 l/min). It is able to set a test condition of high temperature and low temperature. Maximum sodium inventory is about 8 tons. Sodium heater capacity is 800 KW. SGTF specification is suitable for simulating sodium hydraulic, cover gas hydraulic in reactor vessel, demonstration of components, heat transfer performance test of SG tube or erosion test of piping. Various sodium tests for fast breeder reactors (FBRs) have been carried out using these test facilities. They were used for fatigue test, creep fatigue test, immersion test of materials and piping bellows, characteristic test of the motor using under sodium, heat resistant test of self actuated shutdown system (SASS), sliding tests of slide joint, the hydrogen behavior test in the cover gas of sodium, test for heat extension control rod (ETEM), heat transfer flow characteristics of reactor vessel wall (reactor wall cooling test), steam generator tube of 9Cr-1Mo steel, and an ultrasonic sensor under sodium (USAM, etc), for example. MHI has accumulated techniques on sodium by operating sodium test facilities. Purity control, and rinsing method; Heat transfer character, and thermal hydraulics of sodium; Leakage and burning behavior of sodium; Material properties in sodium. SGTF and MTL-3 are now being renewed to improve its reliability and flexibility of operation because it became superannuated. The renewal will be completed in 2009. The control console will be replaced to digital control console. Electro magnetic pump will be replaced. Heaters, cold-traps, and plugging meter will be replaced.Automatic control will be adopted widely, such as heaters, argon gas system, and plugging meter. MHI is going to carry out a lot of sodium tests as the core company of FBR development. Fatigue test, slide or wearing test, immersion test of materials, FSW (Friction Stir Welding) test in sodium will be carried out