Working Principle (Closed-Loop Automatic Pressure Regulation)
1. Liquid Inlet/Heating: Liquid level rises or temperature increases → tank pressure increases → nitrogen release valve opens to release pressure → pressure drops back to the set point and automatically closes.
2. Liquid Outlet/Heating: Liquid level drops or temperature decreases → tank pressure decreases → nitrogen supply valve opens to replenish nitrogen → pressure rises back to the set point and automatically closes.
3. Typical Set Pressure Difference: Nitrogen supply valve approximately 200 Pa, nitrogen release valve approximately 300 Pa, forming a 100 Pa pressure difference band to avoid frequent opening and closing.
Key Structure and Characteristics
• Actuator: Mostly spring-diaphragm type, equipped with a pilot valve for precise pressure setting and sensitive response.
• Valve Body Material: Commonly 304/316L stainless steel or carbon steel lined with fluoropolymer, compatible with PN6–PN16, nominal diameter DN15–DN100.
• Sealing Design: Valve seat sealing surface hardness HRC≥55, equipped with fluororubber O-rings, valve stem uses bellows + packing seal, extremely low leakage rate.
• Control Accuracy: Adjustment range 0.5–5kPa, accuracy up to ±50Pa, suitable for low-pressure conditions.
Application Conditions: Suitable for petrochemical, fine chemical, pharmaceutical, food and other industries, especially suitable for storage tanks storing flammable, explosive, easily oxidized, and highly volatile media, such as methanol, benzene, gasoline, liquid ammonia, and acids.
