Study on Vacuum Exhaust Method and Device for Reactor Primary Loop of Pressurized Water Reactor Nuclear Power Plant

This paper introduces the vacuum exhaust method for the reactor primary loop of Pressurized Water Reactor（PWR） nuclear power plant.It describes the scheme design and operation process of the vacuum exhaust device that is constituted by the temporary cover with sealing ring and vacuum releaser.This is the first time in China for reactor primary loop to be vacuum exhausted during the low-low water level in reactor plant overhaul.It makes the dynamic draining air process not needed,and effectively shortens 10 hours at least in the critical path time of the overhaul,reduces the damage risk of RCP pump,improves the economy and security of reactor power plant operation.