Low-temperature cooling system type TG-LKF for temperature chambers made of glass or metal Temperature range from +100°C to -180°C measured at the internal temperature sensor

Cryogenic cooling in a test chamber

In order to meet the requirements for fast cooling speeds and low temperatures, it is sometimes necessary to switch from conventional thermostat cooling to liquid gas cooling. KGWISOTHERM has developed a new KALTGAS application for this application. Here, a test chamber is cooled using cryogenic nitrogen gas, thus enabling rapid cooling speeds.

KALTGAS is a temperature control system based on the low temperature of liquid nitrogen as a refrigerant. The liquid nitrogen is vaporized in a cryogenic tank by means of a heater (jet). This generates a constant, cryogenic gas flow. By varying the heater (jet), both the cooling capacity and the gas flow volume can be changed, and the LN2 consumption can also be reduced to a minimum by varying the jet output. The cryogenic gas flow is then fed through a vacuum-insulated, flexible metal pipe to a heat exchanger (heater). The heat exchanger has the task of heating the cold gas flow to the desired temperature. This means that a predefined gas flow with a predefined temperature is available as cooling gas at the outlet of the heat exchanger. A KALTGAS system can generate a -170°C cold gas flow within a few minutes. The use of different temperature controllers enables the optimum customized design of a KALTGAS system. Depending on the customer’s requirements, temperature stability of up to +/-0.1°C can be achieved by using an optimized controller. With a standard safety controller (SC5), a temperature stability of less than +/-0.2°C is achieved.

This constant gas flow can be used to control the temperature of a chamber, for example. (see type TGK). Another variant is circulating air temperature control (type TGKU) in a chamber. The air in the chamber is circulated and tempered. This design enables optimum LN2 utilization at temperatures above -20°C.

In addition to the high cooling speed and good control stability, the modular design is another advantage of KALTGAS systems. By replacing individual components, such as the N2 gas line, the jet or the heater, the cooling rate or the LN2 consumption, as well as the type of use, can be changed. The basic modules such as the LN2 tank, vacuum pump or temperature control remain unchanged.

The cold gas system type TG-LKF 63/50 consists of a temperature controller with actual and setpoint value display, a safety controller, a KF-NW 50 siphon with LN2 vaporizer (jet), an evacuable, flexible N2 gas line with built-in reheating module (heater) and a PT100 temperature sensor, as well as a vacuum pump with accessories.

Technical data for:

Type TG-LKF 63/50
(Heater = 630 watts / Jet = 500 watts / LN2 Consumption approx. 1.1 l/h to 11 l/h liters per hour
Pipe V2A, length 1.8 meters, gas outlet nozzle =KF NW 40, can be evacuated with vac. Pump
Lifter for LN2 container with KF NW 50)
Order no. TG-LKF 63/50

Type TG-LKF 63/100
(Heater = 630 watts / Jet = 1000 watts / LN2 consumption approx. 2.2 l/h to 22 l/h liters per hour
Pipe V2A, length 1.8 meters, gas outlet nozzle =KF NW 40, can be evacuated with vac. Pump
Lifter for LN2 container with KF NW 50)
Order no. TG-LKF 63/100

Download cold gas info sheet

Cold gas info sheet as PDF file Download cold gas info sheet

Download cold gas T-G sample manual

Cold gas sample manual as PDF file Download cold gas TG-LKF sample manual


LN2 containers from 20 liters to 300 liters volume Higher + temperatures of KALTGAS systems on request