Material test after endurance test of the primary circulating pump for JOYO

not registered; not registered; not registered

With respect to mechanical sodium pump for the primary cooling system of JOYO, mock-up test has been continued on the pump test loop since April 1972, to demonstrate mechanical and hydraulic performance, and reliability for about 16,000 hrs. Material test after endurance test (about 16,000 hours) has been carried out for sodium bearing, seal ring, spring and impeller, The result is as follows. (1)small extent of pitting and slight carburization were observed in the sodium bearing. (2)small scratches which were probably caused during the installation of the inner casing and eyelashes were observed in the seal ring. (3)the increas of spring constant was found in the spring attached to the seal ring. (4)small hole corrosion on the surface, carburization, and Nickel transfer were observed in the impeller.