Development of technology for improving sealing performance of bolt fastening flange in High Temperature engineering Test Reactor

Hamamoto, Shimpei  ; Fujiwara, Yusuke ; Kawamoto, Taiki; Saikusa, Akio 

A leakage measurement system of primary coolant helium leaked from the bolt fastening flange was constructed at the High Temperature engineering Test Reactor (HTTR). In addition to the helium leakage from the flange, the primary helium pressure, the helium temperature, and the temperature of the flange were measured. The data demonstrated that temperature change of one flange in short-term was associated with tens of percent reduction of helium leakage from bolt fastening flange.