Summary of power ascension test of experimental fast reactor "JOYO" MK-I

Yamamoto, Hisashi*; Sekiguchi, Yoshiyuki*; Hirose, Tadashi*; Sanda, Toshio*; Tamura, Seiji*; not registered; not registered

On April 24th, 1977, the initial criticality of JOYO was achieved and on July 5th, 1978, the reactor output reached rated power of 50 MW for the first time. The 75MW power ascension test was started in July, 1979, followed by two cycles of rated power operations, and the 100 hour nominal power continuous operation was completed in February, 1980. Through the tests for the core, plant it self, radiation shield and plant monitoring, the results proved satisfactory operation characteristics at 75MW. This report presents the summary of an the results obtained in the Test of MK-I core.