A61H/Y-160, A61H/Y-320 type high pressure spring micro-opening safety valve is suitable for equipment and pipelines of air, ammonia, petroleum gas and other media whose working temperature is ≤200℃, A61H/Y-160P, A61H/Y The -320P high-pressure spring micro-opening safety valve is suitable for equipment and pipelines with corrosive gas or liquid at a temperature of ≤200℃, as an overpressure protection device.