Valve Selection for Cryogenic LNG Regasification Terminals

LNG regasification terminals receive liquefied natural gas at −162 °C and convert it to pipeline gas. Each step—ship unloading, storage, vaporization, and send-out—requires valves matched to cryogenic temperatures, high pressures, and demanding safety requirements.

Ship Unloading Arms and Manifold Valves

Cryogenic ball valves and butterfly valves on the jetty manifold handle LNG transfers at −162 °C. These valves are typically type-tested to BS 6364 or ISO 28921-1 for cryogenic service and are actuated for fast remote operation in emergency shutdown scenarios.

Storage Tank Inlet/Outlet Valves

Full-bore cryogenic gate or ball valves on tank nozzles provide primary isolation. Tank isolation valves must be operable under differential pressure conditions and must fail to safe (closed) on loss of control signal. Mechanical position indication confirms valve status from the control room.

Specify double-block-and-bleed at metering connectionsUse extended-stem valves for insulated piping and cold boxesFire-safe certification (API 6FA or BS 6755) required for all LNG service valvesBoil-off gas (BOG) lines require cryogenic valves with low-fugitive-emission packing

Vaporizer Inlet and Outlet Valves

Open rack vaporizers (ORV) and submerged combustion vaporizers (SCV) use globe and gate valves for flow isolation. Vaporizer outlet pressure may be up to 80 bar—pressure class selection must account for both design pressure and maximum allowable operating pressure.

Send-Out and Metering

High-pressure ball valves and control valves regulate gas send-out pressure and flow. Pressure reducing valves (PRVs) and safety relief valves protect the downstream pipeline network from overpressure during send-out operations.

Confirm all cryogenic valves are cold-qualified to service temperatureTest actuated valves at cryogenic temperature before commissioningEstablish regular partial-stroke test schedule for all ESD valvesArchive cold test reports with valve data books