Method for carrying out emergent shaft sealing on reactor coolant pump and shaft sealing assembly

The embodiment of the invention discloses a method for carrying out emergent shaft sealing on reactor coolant pump and a shaft sealing assembly. The method comprises the steps that a passive stopping sealing part is arranged in a first sealing assembly and forms an opening under the normal operation condition, without influencing the first sealing assembly, a liquid film formed by fluid static pressure is used for preventing reactor coolant from leaking along a pump shaft, under the station blackout condition, after sensing high-temperature fluid flowing into the first sealing assembly, the passive stopping sealing part is closed and holds the pump shaft of the reactor coolant pump tightly, the gap between the first sealing assembly and the pump shaft of the reactor coolant pump is blocked, and therefore the reactor coolant is prevented from leaking along the pump shaft. According to the method, the problem of main pump shaft sealing leakage under the station blackout condition is effectively solved, and the damage probability of a reactor core of a nuclear power plant is lowered.