Inflatable oil-gas-free sealing structure of external floating roof oil tank

The invention belongs to the technical field of fire safety of oil storage tanks, and particularly relates to an inflatable oil-gas-free sealing structure of an external floating roof oil tank. According to the technical scheme, the inflatable oil-gas-free sealing structure of the external floating roof oil tank comprises an annular primary sealing structure and an annular secondary sealing structure which are connected to a floating disc, and the primary sealing structure and the secondary sealing structure are located between a tank wall and the floating disc; the secondary sealing structure is connected with an inflatable capsule, an embedded connecting nut is fixed in the inflatable capsule, the secondary sealing structure comprises a rain baffle, one end of the rain baffle is connected to the floating disc, and the embedded connecting nut is connected with the rain baffle through an inflatable capsule fixing piece. One end of the inflatable capsule fixing piece is connected with the embedded connecting n