In the radiology centers of modern hospitals, MRI magnetic resonance imaging equipment is the core equipment for accurate diagnosis and is widely used in key medical scenarios such as tumor screening, neurological detection, and diagnosis of soft tissue lesions. Liquid helium is the only refrigerant that can meet the low-temperature operation requirements of medical superconducting MRI magnets, and has become an indispensable core consumable for MRI equipment by virtue of its extremely low temperature and special quantum physical properties. It can be said that without liquid helium, mainstream clinical MRI equipment will not work properly, and hospitals will be paralyzed in their precise image diagnosis system. In this article, we will analyze the core role of liquid helium in MRI systems.
Liquid helium is a special cryogen (cryogenic refrigerant) formed by the multi-stage cryogenic liquefaction process of helium gas, and is one of the lowest temperature liquid substances known to mankind. Unlike conventional industrial media, liquid helium has unique physical and quantum properties, which are at the heart of why it cannot be replaced by other media.
In terms of basic physical parameters, the boiling point of the most common helium-4 isotope at atmospheric pressure is only 4.22 K, which translates to -268.93 Celsius, while the boiling point of the rare helium-3 isotope is even lower, up to 3.19 K. This extreme low temperature, which is unattainable by all conventional refrigerants, provides an exclusive low-temperature environment for superconducting equipment operation.
Liquid helium has a property that revolutionizes the perception of conventional substances: at standard atmospheric pressure, it remains liquid until absolute zero (0 K) and does not solidify. While most substances solidify near absolute zero, solid helium can only be formed under ultra-high pressure, a characteristic that makes liquid helium far more stable at low temperatures than any other medium.
At the same time, liquid helium is colorless, odorless and chemically inert. As a rare inert gas, it does not chemically react with magnet metals, equipment piping, or air components, and does not corrode MRI precision components, thus ensuring the safety and stability of equipment operation over the long term.
Helium-4 liquid helium exists in two core forms with a cut-off temperature of 2.17K (Ramda point). The physical properties of the two forms differ greatly and indirectly support the need for efficient heat dissipation in cryogenic equipment.
Liquid helium at temperatures above 2.17K is called Helium I. It is a conventional liquid medium that boils and bubbles, and its overall performance is stable enough to meet basic cryogenic cooling needs. The liquid helium used in our medical MRI equipment is basically in the Helium I form.
At temperatures below 2.17K, liquid helium transforms into helium II, the superfluid liquid helium, which is a strange macroscopic quantum state. This form of liquid helium has zero viscosity, flows without any friction, and can even climb along the walls of containers.
In addition, the thermal conductivity of superfluid liquid helium far exceeds that of copper, silver and other high-quality heat-conducting metals, with a thermal conductivity hundreds of times that of copper, and the heat can be rapidly conducted in the medium without temperature gradients. This property allows liquid helium to quickly carry away the minute amount of heat generated by the operation of the MRI magnet and maintain a constant temperature.
Liquid helium cannot be synthesized artificially and can only be prepared through a multi-stage cryogenic liquefaction process. The industry’s mainstay is the Linde and Claude cycles, whereby helium is repeatedly compressed and expanded, with liquid nitrogen assisting in the cooling process, gradually stripping away the heat from the gas, and ultimately realizing the conversion of gaseous helium to liquid helium. The modernized plant can mass produce thousands of liters of liquid helium per day, barely meeting the demand of high-end industries worldwide.
Crucially, helium is an extremely scarce and non-renewable resource. Earth’s helium comes mainly from associated extraction from natural gas deposits, and helium in the atmosphere continues to escape into space, where it cannot be recycled. This has led to limited production of liquid helium, high prices, and a global supply chain that is highly susceptible to geopolitical factors, making it a key resource that constrains the development of healthcare and high-end technology.
Magnetic Resonance Imaging (MRI) enables non-invasive, high-definition, accurate imaging of human soft tissues, and relies at its core on static magnetic fields of high intensity, high uniformity, and ultra-high stability. Unlike ordinary electromagnetic equipment, 1.5T and 3T mainstream MRI equipment used in hospitals cannot rely on conventional copper coils energized to generate a magnetic field.
Conventional metal coils generate great resistance when energized, generate serious heat, and attenuate the magnetic field quickly, which is completely unable to meet the accuracy standards of medical imaging. Only superconducting coils can achieve zero resistance, zero loss, and continuous magnetic field output, and the activation and maintenance of the superconducting state relies entirely on the extreme cryogenic environment of liquid helium. The activation and maintenance of the superconducting state depends entirely on the extremely low temperature environment of liquid helium, which is the core underlying principle that makes liquid helium irreplaceable in MRI systems and an essential consumable for hospitals.
Currently, the superconducting coils in clinical MRI equipment around the world are uniformly made of niobium-titanium (NbTi) alloy. This alloy is the most mature, safe and stable superconducting material in the field of medical superconductivity, and it is suitable for most of the commercial medical MRI equipments, with a popularity rate of nearly 100%.
Niobium-titanium alloys have a pronounced electrical resistance like any other metal at room temperature and at low temperatures in conventional environments. When the device is energized, the coil generates a huge heat loss, which not only consumes a huge amount of electricity, but also leads to unstable magnetic field and constant fluctuations in strength. This state of affairs is completely unable to meet the stringent requirements of medical imaging on the uniformity and stability of the magnetic field.
Niobium-titanium alloys have a fixed superconducting critical temperature, with a standard threshold of 9-10K (about -263°C). When the ambient temperature of the coil drops below this range, the material undergoes a quantum-level physical phase transition, and the resistance instantly drops to absolute zero, formally entering the superconducting state of operation.
Coils in the superconducting state have a unique advantage: the current can circulate indefinitely in the closed coil loop with zero loss. After the device has been energized for excitation, a constant, uniform, high-intensity static magnetic field can be maintained for a long period of time without the need for a continuous external power supply. This stable magnetic field environment is the core foundation for MRI to capture human body’s subtle tissue signals and generate high-definition and accurate images.
In order to avoid temperature fluctuations caused by environmental heat penetration and equipment operation, and to reserve sufficient safety redundancy for superconducting magnets, the industry has uniformly set the standard operating temperature of clinical MRI at 4.2 K. This temperature exactly matches the boiling point of liquid helium under standard atmospheric pressure, which can lock the magnet temperature in the superconducting zone in a long-term, stable and accurate manner, thus guaranteeing the all-weather stability of the imaging of MRI equipment from the root.
Many people wonder whether liquid nitrogen, which is cheaper and more abundantly available, can replace liquid helium for cooling MRI magnets. The answer is no. The core difference lies in the cooling temperature threshold.
Liquid nitrogen has an atmospheric pressure boiling point of 77K (-196°C), which is much higher than the superconducting critical temperature of niobium-titanium alloys, and does not allow superconducting coils to enter a state of zero resistance. If liquid nitrogen is used for cooling, the coil will always be resistive, will continue to heat up, will not be able to form a stable magnetic field, and will not be able to be imaged by the MRI equipment at all.
Among all the conventional industrial refrigerants, only liquid helium can maintain the extreme low temperature of 4.2K, which precisely matches the operation requirements of medical superconducting magnets. Until new high-temperature superconducting MRIs become commonplace, liquid helium is the only viable cooling medium for conventional clinical MRI equipment.
In order to accurately maintain a constant temperature environment for the superconducting coils, MRI equipment manufacturers have designed proprietary sealed cryostat tanks for the magnets, which are the cryogenic core chambers of the entire equipment. The core superconducting components of the device, such as the superconducting coils and the loop leads, are completely sealed inside the cryostat and immersed in a high-capacity liquid helium environment. Adequate liquid helium can wrap the superconducting components in all directions, continuously offsetting the external room temperature and the heat generated by the operation of the equipment, and locking the core temperature of the magnet at a constant 4.2K, ensuring uninterrupted operation of the superconducting state.
In order to minimize the loss of liquid helium through natural evaporation, modern MRI equipment is equipped with specialized cold heads and cryogenic compressors to form a closed-loop auxiliary refrigeration system. This refrigeration equipment operates continuously, actively insulating the liquid helium from external heat penetration and minimizing the boiling loss of the liquid helium. After the cryogenic operation and maintenance system is formed, the superconducting magnetic field of the MRI magnet has strong independence and stability. After the equipment completes the excitation initialization, even if the daily scanning stops and the equipment is powered off, the constant magnetic field inside the magnet will not disappear, and the standby working state can be maintained for a long time.
During long-term uninterrupted operation, a small amount of liquid helium will continue to vaporize and evaporate due to the temperature difference in the machine room environment, slight loss of refrigeration equipment, thermal radiation penetration and other factors, and the industry refers to this routine loss as “boiling loss”.
Hospital operation and maintenance personnel need to regularly monitor the liquid helium level, replenish the helium according to the loss of equipment in a timely manner, and continue to maintain a low-temperature environment to avoid MRI equipment downtime, loss of super and other malfunctions from the root.
MRI equipment of different field strengths, models, and production ages have very different initial liquid helium filling amounts and daily loss amounts. The higher the field strength of the equipment, the higher the requirement for magnetic field stability, the larger the liquid helium capacity required, and the higher the operation and maintenance costs.
1.5T MRI is the mainstream equipment in primary hospitals and routine medical checkups. The initial liquid helium filling volume is generally between 1200-1500 liters, which is sufficient to meet the long-term constant temperature and cooling needs of the equipment, and is suitable for daily large-volume routine checkups.
3T high field strength MRI is mostly used in tertiary hospitals and specialized diagnostic and therapeutic institutions, with higher imaging precision and more stringent requirements for magnetic field stability, and the initial liquid helium filling volume can reach 1,500-2,500 liters, which is the mainstream specification of high-end clinical equipment at present.
7T and above ultra-high field strength MRI is mostly used in scientific research and precision medicine research scenarios, not belonging to the routine clinical equipment, the liquid helium filling volume can be more than 2,500 liters, the cost of consumables and the threshold of operation and maintenance is extremely high.
Liquid helium is not a synthetic material, but is industrially produced from rare helium-rich natural gas deposits through a multi-stage precision separation, purification and ultra-low temperature liquefaction process. Helium is slowly produced by the continuous decay of radioactive elements such as uranium and thorium deep in the earth’s crust and is enriched in specific natural gas deposits. Ordinary natural gas has a very low helium content, with only 0.1% to 7% of special helium-rich fields of industrial value, which directly determines the highly concentrated, non-renewable nature of the global helium resource industry.
Inadequate liquid helium levels and cooling system failures can directly cause MRI magnet temperatures to rise beyond the critical superconducting temperature, leading to what is known professionally as “Quench”. This is one of the most serious failures in hospital MRI operation and maintenance, which will bring about multiple losses in safety, economy and diagnosis and treatment.
When the liquid helium level is insufficient, the cold head fails, or the equipment dissipates heat abnormally, the temperature of the superconducting coil rises rapidly and goes out of superconductivity, and the resistance is restored instantly. The constant current of several hundred amperes in the coil heats up violently and rapidly boils the remaining liquid helium. When the liquid helium vaporizes, it expands 700-750 times in volume, generating enormous air pressure. The equipment rapidly discharges the helium through a special pressure relief pipe, while the magnetic field strength drops from 3T or 1.5T to zero within seconds to minutes, resulting in a complete shutdown of the equipment.
Loss of ultrasound will produce obvious sound and visual effects, the equipment will emit a loud roar, and a large amount of low-temperature white mist will be emitted from the pressure relief port outside the room, which is a normal phenomenon of helium rapid vaporization and discharge. All MRI rooms in regular hospitals are equipped with special pressure relief piping to safely discharge helium to the outside, avoiding the replacement of indoor oxygen by helium, eliminating the risk of asphyxiation, and safeguarding the safety of the personnel in the room.
Hospitals can significantly reduce the risk of overrun and ensure the stable operation of equipment by monitoring the liquid helium level on a daily basis, regularly maintaining the refrigeration system, and setting up a backup power supply system, among other basic means.
The first is the loss of diagnosis and treatment interruption. After the loss of ultrasound, the MRI equipment can not be used at all, and it takes several days or even weeks to recharge helium, cool down the temperature, and debug the excitation, which will cause a large number of patients to be backlogged in the examination, and delay the diagnosis and treatment of tumor, neurological diseases and other serious patients.
Secondly, it is high economic loss. A complete loss of ultrasound will exhaust most of the liquid helium in the equipment, only helium replenishment costs up to tens of thousands of dollars, while violent temperature fluctuations may damage the coil, cryostat tank and other precision components, high maintenance costs, but also a large number of downtime revenue losses.
Finally, the loss of equipment life. Sudden loss of superconducting coils and sealing structures will be subjected to intense temperature stress, and frequent loss of superconductivity will significantly shorten the service life of magnets and increase the cost of early retirement of equipment.
Aiming at the resource characteristics of natural gas with generally low helium content (most of them around 0.03%), Fullcryo, in conjunction with the Institute of Physics and Chemistry of the Chinese Academy of Sciences (IPSC), has proposed a brand new technological route of low-temperature helium extraction from LNG-BOG since 2018, and has overcome the core technological difficulties of low-temperature separation, catalytic dehydrogenation, ultra-purification, and helium liquefaction, and in 2020, it will successfully develop the first set of fully independent complete sets of equipment for helium extraction from LNG-BOG in China. The commercialization demonstration project will be carried out in Yanchi, Ningxia, which will open up the whole process from LNG flash gas feedstock to 5N grade high purity helium and liquid helium output, and the helium extraction rate can reach 97%, and the complete set of equipments will be fully localized and modularized skid-mounted to build up an integrated and independent process system of feedstock pretreatment, crude helium enrichment, low-temperature and deep purification, and helium liquefaction and filling.
1. Independent core helium extraction technology process system
The whole set of process modules is independently developed, covering the whole process of feedstock gas flow stabilization system, catalytic dehydrogenation/dehydration system, crude helium extraction system, cryogenic purification system, helium filling system, etc.; we can obtain high purity helium of 5N grade in accordance with the national standard, and at the same time, with our proprietary intellectual property rights of helium purification and helium liquefaction equipment, we can realize 6N-7N grade ultra-pure helium, which can further expand the high-end industrial applications and significantly reduce the cost of helium transportation. Significantly reduce the cost of helium transportation.
-Extraction efficiency: the helium recovery rate of low concentration natural gas is more than 97%, and a single set of equipment can match the daily processing of 500,000-2.4 million cubic meters of liquefied natural gas plant;
-Product purity: After purification, the crude helium can be refined to ≥99.999% (5N) and 6N electronic grade high purity helium, which is fully compatible with the national high purity gas standard for semiconductor, medical and scientific research;
Process adaptability: support LNG-BOG tail gas, synthetic ammonia release gas and other mainstream industrial helium-containing gas sources, can be added to the existing liquefaction plant technological transformation helium production line, helium efficiency.
2、Industrialization application and industry value
At present, relying on the original LNG-BOG helium extraction technology and standardized equipment, Fullcryo has landed commercial projects in Northwest and Southwest provinces, and has built regional benchmark demonstration projects in Inner Mongolia, Guizhou and other regions, covering a wide range of application scenarios such as conventional LNG plants and shale gas reservoirs, with the annual production of high purity helium reaching 110,000 to 280,000 m3 per year in a single project, and with the device running continuously and stably for more than 10,000 hours. More than ten sets of projects are under construction and delivery.
This innovative technology fully recovers the helium-containing flash vapor from LNG plants, simultaneously reduces the energy consumption and tail gas emission of LNG plants, adds value to the resources, and provides green and energy-saving benefits, forming a new model of natural gas cogeneration of rare helium resources that can be replicated and popularized, and continuing to increase the scale of China’s independent supply of high-purity helium, and providing a stable supply of domestically produced high-purity helium for key fields such as semiconductors, medical and nuclear magnetism, aerospace, and large-scale scientific devices, effectively building China’s high-purity helium supply base. We will continue to enhance the scale of independent supply of high-purity helium in China, and stabilize the supply of domestic high-purity helium for key fields such as semiconductor, medical, nuclear magnetic, aerospace, and large scientific devices, so as to build up China’s capability of independent security of strategic helium resources.
3. Independent manufacturing of liquid helium storage and transportation equipment, and building a national distribution supply chain network.
In the cryogenic storage and transportation sector, relying on Fullcryo’s 40 years of mobile pressure vessel production qualification and accumulation, the company has broken through the industry barriers of cryogenic vessel design and manufacturing, and realized the coverage of extreme temperature zone from liquid nitrogen/liquid hydrogen/liquid helium. At present, we can provide ultra-low temperature liquid helium transportation vehicles/tanks, 1000-10000 liters of cryogenic liquid Kuderbauer, 10-200 cubic meters of cryogenic stationary containers, etc., to realize the independent production of cryogenic storage and transportation special equipment, to make up for the short board of the industrial chain of “post-liquefaction storage, cross-regional transportation”, and to build a national distribution and delivery service system. In addition, the company will open up the logistics chain of liquid helium from the liquefaction base to the end customers.
4. Liquid helium storage and transportation products and transportation:
40-foot standard liquid helium tanks: static evaporation rate of less than 0.4%/d, maintenance time of >42 days, benchmarking the industry’s advanced level;
Various types of liquid helium dewars, small liquid storage tanks, helium high-pressure tube bundle bottles, cryogenic pressure vessels: covering the whole scenario of liquid storage in factories, dispensing at stations, and small-volume distribution at terminals;
Supporting transportation vehicles: cryogenic tank semi-trailers, special helium manifold carriers.
Fullcryo is an enterprise that covers the whole industry chain of helium resource development, helium purification, helium liquefaction, storage and transportation, recycling, and terminal supply, and provides customized solutions according to the needs of the industry, and offers one-stop integrated solutions from helium production, liquefaction, storage and transportation, to terminal distribution, helium recycling, and so on.
The supply chain risks associated with helium scarcity explode completely in 2026 as a common problem facing the global healthcare industry. This is the fifth global helium shortage in the last two decades and the one with the most severe impact, directly impacting the normal operation and maintenance of MRIs in major hospitals.
Helium is a special material with a high concentration of geopolitical resources that cannot be artificially mass-produced, and the global helium supply is highly dependent on a small number of countries. Qatar is responsible for about 1/3 of the world’s helium production capacity, with the United States, Algeria, Australia, and Russia as the secondary suppliers, together controlling more than 75% of the world’s helium resources.
The U.S. Federal Helium Reserve, which once served as a market regulator, has been privatized and withdrawn from the market, leaving the world with no strategic helium reserve buffer, and the global supply chain will break down in the event of a problem in the main production area.
As the geopolitical conflict in the Middle East continues to escalate in 2026, shipping in the Strait of Hormuz is restricted and the large helium production site in Ras Laffan, Qatar, is forced to shut down, taking 27%-33% of the world’s helium production capacity directly offline. According to industry forecasts, it will take 3-5 years to fully restore production capacity in this region.
This precipitous drop in production capacity directly led to a doubling of the global price of liquid helium, and suppliers began to supply limited quotas. Many hospitals suffered helium supply cuts and supply reductions, and had to reduce the number of MRI exams and prioritize the protection of emergency patients.
Medical MRI is the core consumer of helium, accounting for 32% of total global helium consumption. Meanwhile, the semiconductor industry has become the emerging main demand, AI chips, high-end wafer production requires a large amount of helium, the annual demand growth rate of 15%-20%, accounting for more than 21%.
The dual demand of the medical and high-end technology industries superimposed on the tightening of production capacity has continued to intensify the conflict between helium supply and demand, and hospitals are facing greater pressure to cut off supply and increase prices in the competition for resources.
With the normalization of helium scarcity, low-consumption and zero-consumption helium MRI technology has become the mainstream of R&D and popularization of medical equipment worldwide, completely changing the operation and maintenance mode of traditional MRI, which relies on a large amount of liquid helium.
At this stage, sealed low helium magnet technology has become highly mature, requiring only a few liters of liquid helium to realize lifelong operation of the equipment, without the need for daily helium replenishment, completely solving the pain points of volatility loss, loss of super shutdown, and high-priced procurement, and has been widely used in hospitals at all levels.
Meanwhile, high-temperature superconductivity (HTS) MRI technology continues to be iterated, and new devices that do not require liquid helium cooling are accelerating clinical implementation. In the future, helium-free MRI will gradually replace the traditional helium-consuming equipment, completely eliminating hospitals’ dependence on liquid helium resources. For hospitals at this stage, the optimal strategy is to “renovate the stock + upgrade the stock”, installing recycling systems for old equipment, prioritizing low helium models for new equipment purchases, and completing equipment iteration in a gradual manner, balancing operation and maintenance costs and operational stability.
Liquid helium has become an irreplaceable cooling medium for traditional superconducting MRI magnets by virtue of its unique properties of 4.2K extreme low temperature, ultra-high thermal conductivity, and zero-pollution inertia, and is the invisible cornerstone of modern hospitals’ accurate image diagnosis. Liquid helium is used throughout the entire process of MRI operation, from equipment cryostatting, superconducting magnetic field generation to high-definition imaging output.
Fullcryo is a reliable, large-scale supplier of liquid helium for hospital MRI systems, based on its expertise in the global industrial gases and cryogenics industry. In response to the global helium shortage, price volatility and quota restriction that will continue to fester in 2026, Fullcryo has established a diversified helium supply chain to provide hospitals and imaging centers with a stable supply of high purity medical grade liquid helium and on-demand rationing for a long period of time. Contact Fullcryo for professional technical support and long-term helium liquefaction equipment supply solutions.
Q: What is the temperature at which MRI magnets need to be cooled with liquid helium?
Clinical MRI superconducting magnets need to be cooled by liquid helium to a constant temperature of 4.2K (approx. -268.93°C), which can stably maintain the superconducting state of niobium-titanium alloy coils and ensure zero loss and stable operation of the magnetic field.
Q: How much liquid helium is needed for a 3T MRI machine? What is the daily loss?
The initial liquid helium filling volume of a conventional 3T MRI is 1500-2500 liters. Older equipment can lose hundreds of liters per year, while newer zero-volatility equipment has almost no daily loss, and low helium models require only 7-20 liters for life-long sealed use.
Q: Is it dangerous for MRI magnets to lose their super? Will it affect patient safety?
Regular hospital equipment is equipped with a special pressure relief safety system, the helium will be safely discharged in the event of an overrun, no explosion will occur, and there is no direct danger to the lives of patients and medical staff. However, it will lead to emergency shutdown of the equipment and interruption of inspection, resulting in high O&M losses.
Q: Why can’t I use liquid nitrogen instead of liquid helium to cool my MRI magnet?
Liquid nitrogen has a boiling point of 77K, which is much higher than the critical temperature of superconducting coils of 9-10K, and it is impossible for the coils to enter into a zero resistance superconducting state, which can’t support the generation of the MRI magnetic field and high-definition imaging, and is not applicable to conventional medical superconducting MRI equipment at all.
Q: How much cost can hospitals save by building helium recovery systems?
The helium recovery rate of a mature recovery system can reach 80%-95%, which can reduce more than 80% of liquid helium purchases in hospitals, and most hospitals can recover the transformation costs in 1-3 years, with significant long-term cost reduction effects.
