A41H160, A41Y320 single flange micro-open safety valve is suitable for working temperature ≤ 200 °C air, nitrogen and hydrogen mixture, water and other media equipment and pipelines, A41Y160P, A41Y320P type suitable for working temperature ≤ 200 °C corrosive gas or liquid medium equipment and pipelines, as an overpressure protection device. When the pressure in the equipment and pipeline exceeds the allowable value, the valve automatically opens, and then fully discharges, and when the pressure is reduced to the specified value, the valve automatically closes to ensure the safe operation of the equipment and pipeline.