A21H spring micro opening external thread safety valve is suitable for equipment and pipelines with working temperature ≤ 200 ℃ for media such as air, ammonia, petroleum gas, etc. The A21W type is suitable for equipment and pipelines containing corrosive gases or liquids with a working temperature of ≤ 200 ℃, while the A21F type is suitable for equipment and pipelines containing liquefied gas, petroleum gas, etc. with a working temperature of ≤ 200 ℃, as an overpressure protection device. When the pressure inside the equipment and pipeline exceeds the allowable value, the valve will automatically open and then discharge the full amount; When the pressure drops to the specified value, the valve automatically closes to ensure the safe operation of equipment and pipelines. Working temperature A21H type ≤ 200 ℃ A21W type ≤ 200 ℃ A21F type -40 ℃~80 ℃

Main overall dimensions