Manhole door structure of bag-type dust collector

The utility model provides a bag-type dust collector manhole door structure which comprises a box body, a sealing cover, a fixing piece, a first sealing ring and a second sealing ring, and the box body is used for being connected with a dust collector main body; the sealing cover covers the open end of the box body, the sealing cover comprises a cover plate and a sealing ring annularly arranged on the outer edge of the cover plate, the sealing cover further comprises a limiting ring connected to the cover plate, the limiting ring and the sealing ring are coaxially arranged, an annular installation space is formed between the limiting ring and the sealing ring, and the sealing ring is arranged in the annular installation space. The sealing ring is arranged on the outer side of the box body, and the limiting ring is located on the inner side of the box body; the fixing piece is arranged outside the box body in a sleeving mode and located below the sealing ring. The first sealing ring is arranged in the mounting