Low-temperature cooling system type TG-LKF-H 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. KGW-ISOTHERM has developed a new KALTGAS application for this application. Here, a test chamber is cooled using cryogenic nitrogen gas, enabling rapid cooling speeds. To facilitate the handling of the cold gas hose, the heater of the cold gas hose was placed on the siphon of the container in this version. This change has considerably simplified the connection of the cold gas hose.

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 container using a heater (jet). This generates a constant, cryogenic gas flow. By varying the heater (jet) on the safety controller (SC5), 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 power. 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 cold gas hose. A KALTGAS system can generate a -180°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. 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-H 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-H 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)

Best. No.: TG-LKF-H 63/50-1 (external thread)
Best. No.: TG-LKF-H 63/50-2 (union nut)
Best. No.: TG-LKF-H 63/50-3 (Johnston clutch)
Best. No.: TG-LKF-H 63/50-4 (Swagelok)
Best. No.: TG-LKF-H 63/50-5 (female thread)

Type TG-LKF-H 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
Siphon for LN2 container with KF NW 50)

Best. No.: TG-LKF-H 63/100-1 (external thread)
Best. No.: TG-LKF-H 63/100-2 (union nut)
Best. No.: TG-LKF-H 63/100-3 (Johnston coupling)
Best. No.: TG-LKF-H 63/100-4 (Swagelok)
Best. No.: TG-LKF-H 63/100-5 (female thread)

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-H sample manual


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