Flange sealing structure, rear axle and engineering machinery

The utility model discloses a flange sealing structure, a rear axle and engineering machinery. The flange sealing structure comprises a rotating shaft, a flange, a sealing assembly and a sealing assembly, the flange is arranged at the end part of the rotating shaft; the axial fixing part is used for fixing the flange on the rotating shaft, so that the flange rotates along with the rotating shaft; the sealing assembly is installed in an inner hole of the end cover and makes contact with the circumferential face of the flange. The multiple limiting components are stacked together to be installed in an inner hole of the end cover and used for axially limiting the sealing assembly, and the sealing assembly makes contact with the circumferential faces of the flanges at different positions by increasing or decreasing the number of the limiting components. According to the technical scheme disclosed by the utility model, the problems of quick abrasion and short service life of a shaft type rotary sealing element are