Need a valve that can handle -320°F liquid nitrogen without freezing up — and still control flow? Here’s a proven configuration ValveMan supplied for a cryogenic control application.
- Cryogenic ball valve with Kel-F seats
- Full port ball for low pressure drop
- Cryogenic extension to keep packing/actuator away from the cold zone
- Spring-return pneumatic actuator for fail-close
- 30° V-ported ball for better control (throttling)
- 4–20 mA control from the PLC for modulation (typical via an I/P or positioner)
ValveMan was contacted by an American Petroleum Institute (API) testing facility that needed a valve that could pass liquid nitrogen through it without freezing when operated. They also needed to control the amount of nitrogen entering a tank while the process fluid remained at -320°F.
ValveMan recommended one of our premium actuated cryogenic ball valves with Kel-F seats, a full-port ball for low pressure drop, and a spring-return pneumatic actuator so the valve would fail closed (more cost-effective than spring-return electric in this case).
To prevent freeze-up at the stem packing/actuator area, we also specified a cryogenic extension, which moves the packing gland and actuator away from the cold zone.
Because the customer needed controllability on the discharge side, we supplied a 30° V-ported ball. The configuration allowed the customer to take a pressure transmitter signal on the discharge side, feed it into their PLC, and modulate the valve with a 4–20 mA control signal to maintain target pressure. The system has been very successful.
Need help selecting a valve for liquid nitrogen or other cryogenic service? Contact the ValveMan valve store and we’ll help you size and specify the right configuration.
