Large-caliber quick-opening blind plate

The invention relates to the field of quick-opening blind plates, in particular to a large-diameter quick-opening blind plate which comprises a blind plate cover, a blind plate seat, a double-opening-closing mechanism, a double-clack type hoop and a rotating arm mechanism. The blind plate cover and the blind plate base are hinged through the rotating arm mechanism, and the rotating arm mechanism is used for achieving opening and closing of the blind plate cover and the blind plate base. The periphery of the closed part of the blind plate cover and the blind plate seat is provided with a bivalve type hoop which is used for connecting the closed blind plate seat and blind plate cover into a whole; the two double-opening and closing mechanisms are arranged at the two radial ends, perpendicular to the opening and closing direction of the blind plate cover, of the blind plate base respectively and used for controlling opening and closing of the two parts of the double-clack type clamp. According to the quick-openi