Abstract: A liquid cryogen dosing head has a liquid cryogen reservoir in communication with a dosing outlet, a dosing valve stem having a lower, distal end configured to selectively open and close the dosing outlet, and an electromagnetic actuator attached to an upper end of the dosing valve stem above the liquid cryogen reservoir and operable to move the dosing valve stem to open and close the dosing outlet. The electromagnetic actuator is disposed above the liquid cryogen reservoir and the dosing valve stem extends through the liquid cryogen reservoir, preferably concentrically, to open and close the dosing outlet by blocking an orifice of the dosing outlet.

Abstract: An aseptic liquid cryogen dosing head has a liquid cryogen reservoir in communication with a dosing outlet. An electromagnetic actuator is attached to an upper end of a dosing valve stem and is operable to move the dosing valve stem to open and close the dosing outlet. An air-tight seal extends about the dosing valve stem and separates the liquid cryogen reservoir from a cavity between the seal and the electromagnetic actuator. A controller is operable to perform a head leakage test, including pressurizing the cavity with a pressure higher than a pressure within the reservoir, to check for leakage past the seal; and pressurizing the reservoir to check for leakage from the liquid cryogen reservoir.

Abstract: An aseptic liquid cryogen dosing head has a liquid cryogen reservoir in communication with a dosing outlet. An electromagnetic actuator is attached to an upper end of a dosing valve stem and is operable to move the dosing valve stem to open and close the dosing outlet. An air-tight seal extends about the dosing valve stem and separates the liquid cryogen reservoir from a cavity between the seal and the electromagnetic actuator. A controller is operable to perform a head leakage test, including pressurizing the cavity with a pressure higher than a pressure within the reservoir, to check for leakage past the seal; and pressurizing the reservoir to check for leakage from the liquid cryogen reservoir.