What Is Cryogenic Test Chamber And How To Perform The Low-Tempreture Test With It

Cryogenic Test Chamber, also known as ultra-low temperature refrigerator, refers to the mixed working medium as the refrigerant, in the extremely low temperature of the workpiece processing device. It can significantly improve the toughness of the workpiece without reducing the strength and hardness of the workpiece. It can effectively improve the mechanical properties and service life of iron and steel materials, non-iron metals and composite materials, stable size, improve uniformity, reduce deformation, and simple operation, no damage to the work piece, no pollution, low cost, has a positive application prospect and development space.

Application field of Cryogenic Test Chamber

Low temperature testing is generally used in the following industries:

Two types of Cryogenic Test Chamber

Liquid nitrogen refrigeration is a process that uses the phase transition properties of liquid nitrogen to achieve cooling. As liquid nitrogen evaporates, it absorbs heat from its surroundings, resulting in a decrease in the temperature of the environment in which it is located. Liquid nitrogen refrigeration is commonly used for specific applications in laboratory and industrial production, such as the manufacture of superconductors and cryopreservation of materials. 

Liquid nitrogen deep freezer uses liquid nitrogen as cold source. Liquid nitrogen is stored in the cryogenic liquid tank, when using, first close the vent valve of the liquid nitrogen tank, and then open the booster valve, because part of the liquid nitrogen gasification makes the internal pressure of the liquid nitrogen tank, at this time to find the liquid nitrogen outlet valve, the liquid is pressed out from the storage tank, through the moving film regulating valve into the deep cold box. Liquid nitrogen into the deep freezer, through the nozzle ejection, because the box temperature is higher than the temperature of liquid nitrogen, so it quickly gasification, and volume expansion, so that the temperature drops, axial flow fan will be low temperature nitrogen blowing into the studio, so that the workpiece cooling.

Mechanical refrigeration provides cooling by compressing and relaxing certain gases, including chlorofluorocarbons, ammonia, and carbon dioxide. Mechanical refrigeration technology is widely used in domestic and commercial refrigeration equipment, air conditioning systems and industrial cooling processes.

Mechanical refrigeration Deep cold boxes use the principle of compression refrigeration cycle to reduce the temperature inside the box. It works as follows:

1. Compressor: Mechanical refrigeration The deep cold box has a built-in compressor, which can compress refrigerant gas at low temperature and low pressure into gas at high temperature and high pressure.

2. Condenser: High temperature and high pressure gaseous refrigerant is cooled by the condenser and becomes high pressure liquid refrigerant.

3. Expansion valve: high-pressure liquid refrigerant enters the evaporator through the expansion valve and becomes low-pressure liquid refrigerant after decompression.

4. Evaporator: Low pressure liquid refrigerant evaporates in the evaporator, absorbing the heat in the box and reducing the temperature in the box quickly.

5. Return pipe: The evaporated refrigerant flows back to the compressor in the return pipe and continues to be used for refrigeration.

Through the continuous cycle of compression, cooling, expansion, evaporation, reflux and other processes, mechanical refrigeration deep cold box can reduce the temperature in the box to a lower temperature, in order to meet the needs of different fields for temperature.

The biggest difference between the two refrigeration methods is their principles, liquid nitrogen refrigeration is based on phase transitions and thermodynamic principles, while mechanical refrigeration is based on gas compression and expansion processes. Liquid nitrogen refrigeration is more suitable for low temperature and small scale applications, while mechanical refrigeration is more suitable for large scale commercial and industrial applications.

LIB Cryogenic Test Chamber uses mechanical cooling instead of traditional liquid nitrogen cooling for the following reasons:

•  The cost of using liquid nitrogen is 7–10 times that of using cryogenic units.
• Ultra-low temperature units can accurately control temperature, while liquid nitrogen temperature control is difficult.
•  The high cost of liquid nitrogen procurement, transportation and storage is solved.

How the cryogenic test chamber is used to test the test parts (taking aerospace parts as an example)

The following is the operation process of the deep-freezing chamber for aerospace parts testing:

1. Preparation of test parts: The aerospace parts to be tested are placed in the deep-freeze chamber. Test parts should be pre-checked and tested to ensure they meet the test requirements.

2. Set the temperature and time: according to the test requirements, set the temperature and test time in the deep freezer. Deep freezer can usually reach very low temperatures, such as minus 100 degrees Celsius or below.

3. Open the deep freezer: turn on the deep freezer and let its temperature drop to the required temperature after a period of time, and start the test after the temperature stabilizes.

4. Execute the test: Run the test program at the set temperature. The type of test may vary depending on the type of test piece and the test requirements. For example, the test may involve factors such as electrical, mechanical or thermal properties.

5. Record Data: Record the data and results during the test. Due to the extreme conditions of the test environment, the deep freezer test may produce deviations in the experimental results, so sufficient data needs to be recorded to ensure accurate conclusions are obtained.

6. End of the test: Close the deep-freeze chamber after the test is complete. The test piece can be removed and further tests can be performed to confirm the test results.

7. Data analysis and reporting: Based on the recorded data and results, perform data analysis and generate a test report. The report should include the test process, test results and conclusions, and make necessary corrections and improvements.

Product recommendation

Cryogenic Test Chamber

Cryogenic Test Chamber

The LIB cryogenic test chamber is the perfect solution for anyone who needs to test their products in extremely cold conditions. With a temperature range from -120 °C to 150 °C, triple cooling, energy efficient, environmentally friendly components, customizable dimensions, stable performance, and excellent after-sales service, our products offer everything needed for a cryogenic test chamber.