Cryogenic Safety Valves — LNG, Industrial Gas & Low-Temperature
Cryogenic systems storing and transporting liquefied gases (LNG, nitrogen, helium, argon) present unique safety challenges at extreme low temperatures. Aquatrol’s cryogenic relief valves are engineered for liquid and vapor service, use materials rated to -300°F/-184°C and below, and include vapor pressure vent designs preventing liquid hammer and rapid pressure rise. Custom sizing for cryogenic applications—request a quote.
Cryogenic Pressure Relief Expertise
Cryogenic liquids boil violently if pressure drops or temperature rises, generating high vapor pressure instantly. Standard relief valves designed for room-temperature service fail catastrophically at cryogenic temperatures—seals freeze, springs lose temper, and metals become brittle. Aquatrol’s cryogenic series use special low-temperature elastomers, hardened internals, and vent designs specifically engineered for vapor and liquid transitions.
Sizing a cryogenic relief valve requires understanding vapor pressure curves and liquid/vapor equilibrium specific to your cryogenic fluid. LNG stored at -320°F generates different pressure dynamics than cryogenic nitrogen at -300°F. Our engineers calculate worst-case boiloff and emergency depressurization requirements to size your relief correctly.
Vent design prevents dangerous phenomena like liquid hammer and uncontrolled vapor discharge. We specify inline vent accumulators, vapor expansion chambers, and safe vent routing that protects equipment and operators. Regulatory compliance—ASME, API, ISO, and cryogenic industry standards—is verified for every system.
| Series | Media | Temp Range | Pressure Range |
|---|---|---|---|
| 560 | LNG, nitrogen, helium | -300°F to 150°F | 30–1,000 PSIG |
| 561 | Liquid hydrogen | -400°F to 100°F | 50–500 PSIG |
| 562 | Ethylene, other cryo | -290°F to 120°F | 30–800 PSIG |
| 563 | Dual liquid/vapor | -300°F to 150°F | 50–1,000 PSIG |
| 564 | High-capacity cryo | -300°F to 150°F | 50–1,500 PSIG |
Common Applications
- LNG storage tank and truck/ship relief valve
- Cryogenic nitrogen storage and distribution
- Liquid helium and argon system relief
- Hydrogen and specialty cryogenic service
- Industrial gas plants and liquefier protection
- Research laboratory cryogenic equipment
- Emergency depressurization and safety venting
Need Help Choosing the Right Valve?
Our valve engineers can help you select the perfect valve for your application.