Apparatus for controlling level of cryogenic liquid

An apparatus for transferring cryogenic liquid, comprising a vessel for containing a cryogenic liquid, a pressure tank for holding a supply of the cryogenic liquid and having a sealed cover, and a transfer duct connected to transfer liquid from the tank to the vessel by pressure in the tank;

• the transfer duct comprising a transfer line connected to transfer liquid from the tank, a vessel inlet section sealed into the cover, and a duct section connected between the transfer line and the inlet section;
• the duct section comprising a duct housing with an exhaust channel therein, and a liquid injection tube extending therethrough, the injection tube being connected to pass liquid from the transfer line, the housing duct having an exhaust port proximate the transfer line and, oppositely the exhaust port, an opening into the inlet section;
• and
• the inlet section comprising a cylindrical outer baffle extending downward from the ducting section into the vessel substantially below the operating level, a cylindrical inner baffle mounted coaxially within the outer baffle so as to define an annular space therebetween, and an injection end of the injection tube extending partially into the inner baffle, the injection tube having an exit end below a nominally minimum operating level, the outer baffle having one or more exhaust vents located in the vessel above a nominally maximum liquid level so as to exhaust gas from above the liquid level in the vessel through the duct housing to the exhaust port, and the inner baffle having an upper end located below the exhaust vents and a lower end located above that of the outer baffle, whereby liquid under pressure from the tank is injected under pressure from the tank into the vessel with a minimum of physical and thermal turbulence.