Rubber gasket for anti-disengaging flange and use method of rubber gasket

The invention provides a rubber gasket for an anti-disengaging flange and a use method of the rubber gasket and belongs to the field of irrigation flange sealing. The rubber gasket comprises an annular rubber washer. The external diameter of the rubber washer is larger than the external diameter of the connecting end of the flange. A limiting protruding rib is arranged at one end of the rubber washer, the outer edge of the rubber washer is of a reverse hook structure facing the end where the limiting protruding rib is located, a plurality of sealing protruding ribs are arranged at the other end of the rubber washer, and the limiting protruding rib, the reverse hook structure and the sealing protruding ribs are of annular structures coaxial with the rubber washer. The rubber gasket solves the problems that it is very hard to accurately arrange an existing rubber gasket to a pipe network system, troubles are brought to construction, the construction progress is delayed, the rubber gasket is prone to disengaging