Sealing pad and flange sealing device

The invention discloses a sealing pad and a flange sealing device. The sealing pad comprises a bottom plate part, wherein a plurality of protruding parts protruding out of the plane in which the protruding parts are located are formed on the bottom plate part, limiting parts which are increased relative to the protruding parts are formed on the protruding parts, and through holes penetrating through the whole sealing pad are formed in the protruding parts. According to the sealing pad and the flange sealing device, when the sealing pad and the flange sealing device are used, the protruding parts are arranged in mounting holes, the bottom plate part and the limiting parts are located on the two sides of the mounting hole, pre-fixing of the sealing pad and a connecting flange can be achieved, the sealing pad cannot fall relative to the connecting flange in the moving process of the connecting flange, construction operation is facilitated, and unnecessary trouble is avoided; the limitingparts can play a function