Stack top fixed shielding device for sodium cold rapid stack

The utility model discloses a reactor top fixation shielding device used for a sodium-cooled fast reactor, which is a box-shaped structure that is mainly composed of a ventilation cover, a shielding casing, an annular skirt plate and a sealing assembly; wherein the ventilation cover is connected on the shielding casing, cooled air enters the ventilation cover from an air inlet pipe, and then flows into the shielding casing after being converged in the ventilation cover, the shielding casing is provided with a horizontal wind channel, and the shielding casing comprises a steel plate layer with hole channels, a slag cotton layer, and a concrete layer. The device has simple structure, convenient operation and provides a work platform for reactor operation and equipment maintenance, and is independent.