A 4.5K helium refrigeration system is one of the most critical subsystems in modern synchrotron facilities. It provides continuous cooling for superconducting RF cavities and ensures stable accelerator operation. Recently, a 500W@4.5K helium refrigerator was installed at the Hefei Advanced Light Source (HALF).
In modern large-scale scientific facilities, ultra-low temperature technology has become an important basis for supporting cutting-edge scientific research. Among them, 4.5K (about-268.65℃) helium refrigeration system is the core equipment to maintain stable operation of superconducting equipment, widely used in synchrotron radiation light source, particle accelerator, fusion device, quantum computing platform and aerospace and other fields.
Compared with liquid nitrogen refrigeration (77K), liquid helium can provide lower operating temperature, so that superconducting materials maintain zero resistance state, thus ensuring long-term stable and efficient operation of equipment. Therefore, helium refrigeration systems are often referred to as the “cryogenic heart” of large scientific devices.
Synchrotron radiation light sources are known as “super microscopes” for observing the microscopic world. They can generate X-rays with extremely high brightness and high coherence, providing an important scientific research platform for materials science, biomedicine, semiconductors, energy and other fields.
Superconducting RF cavities are important components of accelerating electron beams, and these superconducting cavities can only maintain superconducting state at an extremely low temperature of about 4.5K. Once the temperature fluctuates, the superconducting material loses its superconducting characteristics (Quench), causing the entire acceleration system to interrupt operation, seriously affecting the experimental progress.
Therefore, a helium refrigeration system that can provide 4.5K low temperature environment stably for a long time directly determines the operation reliability of synchrotron radiation light source.
Unlike ordinary industrial refrigeration equipment, large research helium refrigeration systems need to meet a number of stringent requirements at the same time, including:
At the same time, the compressor, turboexpander, heat exchanger, cold box, cryogenic measurement and control system and other core components need to work highly together, any link problems may affect the stable operation of the whole system.
Therefore, companies that can independently complete the design, manufacture, installation and commissioning of large-scale helium refrigeration systems are few in the world.
Recently, Hefei Advanced Light Source (HALF) project ushered in an important construction node-500W@4.5K large-scale helium refrigeration system independently developed and manufactured by Fullcryo successfully completed on-site delivery and officially entered the installation and commissioning stage.
As the core equipment of HALF cryogenic system, this set of equipment includes many key components such as large vacuum cold box, turboexpander, cryogenic pipeline and control system. Due to the large size and high weight of the equipment, the project team has carried out special transformation for the transportation route, comprehensively optimized the gradient of underground passage, road bearing capacity, turning radius, etc., finally realized the safe and accurate positioning of the equipment, creating conditions for subsequent installation.
Before leaving the factory, the system has completed the cold state test of the whole machine.
With the development of superconducting technology and cryogenic engineering, the application of 4.5K helium refrigeration system is not limited to synchrotron radiation source.
Currently, it is widely used in:
In the future, with the continuous development of global large scientific devices and advanced manufacturing industries, high-performance large-scale helium refrigeration systems will play a more important role in Basic scientific research, high-end manufacturing and strategic emerging industries.
Large-scale helium refrigeration system is not only a set of refrigeration equipment, but also a key basic equipment supporting superconducting technology and major scientific infrastructure. For the future synchrotron radiation, fusion energy, quantum technology and aerospace fields, stable, efficient, autonomous and controllable helium refrigeration technology will continue to provide solid support for more major scientific research platforms.
