Automatic overpressure exhaust valve

The invention relates to an automatic overpressure exhaust valve which comprises an air inlet (1), a valve body (2), a valve base (3), a movable disk (4), a valve cover (5) and an exhaust port (6), wherein the air inlet is formed in the bottom of the valve body and is provided with a hose (7); the valve base (3) is communicated with the valve body (2) through the hose (7) and supports the valve body; the valve base and the valve body are fixed by leveling screws (8); the movable disk (4) is mounted above the valve base; and the movable disk is a gravity type valve sheet. At least three leveling screws are arranged between the valve base and the valve body; and a bubble level indicator is arranged at the top end of the valve base. After the structure is adopted, when the pressure in the pipeline communicated with the air inlet exceeds a designed pressure value, the movable disk is opened automatically in a vertical direction to discharge the gas; and when the discharge pressure is lower than the designed pressure, the movable disk drops automatically and vertically to prevent the gas from being discharged.