Over Design Load Vibration Test of Piping Support in JOYO

Isozaki, Kazunori ; Tomita, Naoki

The mechanical and oil snubber type piping supports have been installed and used in the piping system including the primary and secondary cooling system in order to restrain the vibration caused by the earthquake in the experimental fast reactor "JOYO". The piping supports moves with pipe corresponding to slow displacement such as thermal expansion of the pipe. On the contrary, when the earthquake happens, it restrains the rapid vibration mechanically or hydraulically. Manufacture guarantees that the piping support can stand the vibration up to 150% load of design specification.The piping support in JOYO could stand the vibration in excess of design value, but the upper limit of the vibration had not been obtained. In order to grasp the upper limit, vibration tests were carried out using the same type piping support as installed in the primary and secondary cooling system. As a result of the vibration test, it was confirmed that the vibration restraint function of piping support could be maintained up to 6 times higher design value. This result will be used for reasonable review of the earthquake-proof design, evaluation of the components and piping system residual lifetime.