Suction barrel for improving natural circulation capacity of reactor

The utility model discloses a suction cylinder for improving the natural circulation capacity of a reactor. The suction cylinder comprises a cylinder body and a cylinder cap arranged at the top of the cylinder body, a heat insulation gasket is arranged on the inner wall of the cylinder body, a flow guide channel is formed in the cylinder body, and flow guide channel grids are arranged in the flow guide channel; the diversion channel grid and the heat insulation liner are integrally formed, the diversion channel grid is a columnar structural member with a plurality of grid channels, the plurality of grid channels are in one-to-one correspondence with the grids of the reactor core fuel assembly, the grid channels form a coolant flow channel, one end of the diversion channel grid is flush with the bottom of the barrel body, and a coolant flows through the reactor core and is heated and then flows through the heat insulation liner. The barrel body enters the suction barrel; compared with the prior art, the suctio