What is Cryogenic Liquid Pump and Why Do We Use Them?

05, Jun. 2025

 

Cryogenic pumps: types and uses in industry | Cryospain

Cryogenic pumps are a central element to many engineering structures and, as such, the choice of a cryopump plays a crucial role in guaranteeing their efficiency and optimization. 

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What is a cryogenic pump and what types of systems can cryogenic pumps suppliers offer? Keep reading to find out in this short guide about cryogenic pumps.

The usefulness of cryogenic pumps

A cryogenic pump or a cryo pump is a type of cryogenic equipment in charge of the transfer and pressurization of liquefied gasses.

A cryopump’s power depends on the freezing and boiling points of the choice of gas. As such, it is used for cryogenic fluid applications including LNG (liquefied natural gas), methane, ethane, propane, butane, among other substances.

The cryopump thus plays a key role in many processes involving pure and mixed industrial and technical gasses. 

Some of the main applications for cryogenic pumps include: 

Air separation units (ASU)

  • Process and transfer applications at cryogenic temperatures
  • Unloading operations from tankers
  • Air separation units (ASU)
  • Bunkering 
  • Gas transportation operations

On the other hand, it’s important to differentiate cryogenic pumps from a cryo vacuum pump. The latter  is a type of pump that works by trapping and accumulating gasses and condensing them on a cold (cryogenic) surface. 

This surface is part of the pump and is meant to create high-vacuum and ultra-high vacuum conditions, which help storing the gas molecules. 

It is also able to produce a higher pumping speed than other pumps and clean vacuum environments, avoiding the entrance of oil. 

Because the cryogenic vacuum pump is based on an accumulation system, it must also exhaust gasses periodically and regenerate them. In order to guarantee an efficient evacuation in this ultra-high vacuum environment, this type of pump then evacuates gasses using an equilibrium pressure for adsorption of less than 10-8Pa.

Some additional functioning features of these systems typically include: 

  • They are cooled by compressed helium, liquid nitrogen, dry ice and other options.
  • Baffles may be added to expand the cryogenic surface for condensation.
  • Close-cycle refrigerations are generated by two-stage cold head cylinders which are enhanced by drive unit displacer assemblies. 

In what industries are cryogenic pumps used?

Marine industry

The marine industry is mainly in need of cryogenic pumps for bunkering applications related to Liquefied Natural Gas supplying processes. 

Demand for this sort of system is growing as (LNG) gains traction and represents a greener alternative in the marine industry, which is facing the challenge of decarbonization and moving towards more sustainable energy sources.

Automotive sector

As the automotive sector advances in finding alternatives, more sustainable fuels, the demand for reliable cryogenic pumps suppliers grows in this industry. Accordingly, cryopumps are installed in LNG and compressed natural gas (L-CNG) refueling stations. 

Industrial and manufacturing sectors

Cryogenic pumps are a crucial tool in many industrial applications in need for pure technical gasses stored at cryogenic temperatures. Steel production and the manufacturing of electronics are two examples of such applications.

Other sectors

Other industries in need for cryogenic pumps include the medical sector, oil fields, aerospace applications and space programs or material research processes, among others.

Keep reading: Tips and tricks for good cryogenic pump maintenance

Types of cryogenic pumps and their differences

1. Centrifugal cryo pump

The cryogenic centrifugal pump (also known as receiver or generator) transforms mechanical energy of an impeller or runner into kinetic or pressure energy. Using centrifugal forces, it expels cryogenic liquids to the outside.

The centrifugal cryogenic pump is adequate for dealing with LNG, nitrogen, oxygen, ethylene, hydrogen and carbon dioxide, among other cryogenic gasses. 

This type of cryopump includes the following features

  • Can be operated using gears and a fixed-speed motor or coupled to variable speed motors.
  • They can be powered by electric motors with direct transmission as well as hydraulic power.
  • Higher capacities and pressures can be achieved if a yearbox is included between the motor and the pump.
  • The cold box must include a gas-seal.

This category may include multiple functioning systems, from one or two-stage pumps to stationary pumps, pumps on tankers and removable pumps. 

Additionally, at Cryospain we’re able to provide turnkey-type, tailor-made pumping solutions, including stationary centrifugal pumps mounted on chassis with all the required instrumentation. We also extend the life cycles of our centrifugal cryogenic pumps by using composite materials for mechanical seals, instead of conventional graphite seals.

The centrifugal cryogenic pump has many applications, including maritime bunkering, submerged marine fuel systems and liquid storage transferences, among others.

For more information, please visit Chengde Energy Technology.

2. Piston or reciprocating cryogenic pumps

As cryogenic pumps suppliers, we also provide piston or reciprocating cryogenic pumps ranging from MRP pumps (used for the high-pressure filling of air gasses) to specialized pumps for the use of LNG, hydrogen, and other liquefied gasses.

Reciprocating cryo pumps compress liquids using piston movements at high pressures. This results in dislodging the fluid volume equivalent to that which it occupies during its stroke.

Reciprocating cryogenic pumps are used in many applications, including high-pressure LNG and air gasses applications. Both single and double electric motor systems are available, as well as single and multi-stage versions. 

This type of cryopump is useful for many applications, including high-pressure pumping, and the filling of storage systems for cryogenic substances such as LNG, LN2, LH2, among others.

3. Submerged pumps

Submerged cryogenic pumps are used when low temperatures are needed for liquids to be transported. As a consequence, they’re a common feature in the production and transport of liquid nitrogen, liquid natural gas (LNG), liquid Helium, and liquid Oxygen and in ship to ship bunkering processes.

At Cryospain we develop tailored cryogenic equipment as part of our comprehensive innovative engineering projects. We thus are in charge of supplying cryogenic equipment components and devices, including cryogenic pumps for the industry’s most renowned companies.

Through our top engineers, designers and experts, we’re able to generate efficient and optimized cryogenic equipment, customizing it to our clients’ specific needs. 

In terms of cryogenic pump maintenance, incorrect processes may result in poor motor performance or poor insulation, leading to repeated part replacements and consequent reduced service life. Because of this, as part of our commitment to generate the highest-quality systems, we provide maintenance and after-sale services, guaranteeing our clients’ investments remain cost-efficient and our equipment is both safe and optimized at all times.

What is a Cryogenic Pump? - Provac Sales

Have you ever considered the role of a basic device such as a pump in driving groundbreaking advancements across sectors such as medicine, aerospace, and energy? Consider the unique world of cryogenic pumps, where the ordinary becomes exceptional. Imagine a machine with the capability to manage substances at temperatures significantly below freezing, unveiling possibilities once perceived as unattainable.

A cryogenic pump, built purposely for the most frigid environments, typically functioning at temperatures below -150°C (-238°F), is a perfect example. However, it is not solely the sub-zero conditions that distinguish cryogenic pumps; it is their extraordinary capacity to manipulate substances within these difficult conditions.

At its core, cryogenic pumps excel in the transport, compression, and precise control of cryogenic fluids—substances cooled to remarkably low temperatures. These pumps support a wide range of important tasks, from preserving crucial biological samples in labs to helping launch rockets into space.

How Does a Cryogenic Pump Work?

At their core, these pumps are intricate devices crafted to handle substances at temperatures that would freeze most equipment in its tracks.

The key to the functioning of cryogenic pumps lies in their close affinity with low temperatures. Just as your car engine relies on gasoline for power, cryogenic pumps depend on extreme cold to perform their wonders. But why? What is it about the cold that enhances their effectiveness?

A cryogenic pump adeptly manipulates ultra-cold substances, enabling precise control and transportation. Even though it's not filled with technical terms, this comparison helps us understand how cryogenic pumps deal with very cold temperatures.

Types of Cryogenic Pumps

Cryogenic pumps come in various types to suit different needs and tasks. Before we explore their fascinating applications, let's learn about these pump categories.

Cryogenic pumps can be classified into two primary groups: centrifugal and positive displacement pumps, each characterized by their unique traits and strengths.

Centrifugal Pumps: Imagine centrifugal pumps as the sprinters of the cryogenic world. They work by spinning an impeller to create a fast flow of icy-cold fluid. This quick movement lets them move lots of fluid quickly but not over long distances.

Positive Displacement Pumps: Now, positive displacement cryogenic pumps are more like marathon runners. They use a different method, like filling and emptying small chambers, to push cryogenic fluids. This way, they have precise control and can handle high-pressure jobs.

Applications

Now that we've sorted out the differences between centrifugal and positive displacement cryogenic pumps, let's dig into where each type really shines. They're put to work in various industries, adapting to the specific needs of each.

Centrifugal Pump Applications

  • Liquefied Natural Gas (LNG) Facilities: Centrifugal cryogenic pumps play a crucial role in turning natural gas into a liquid form for easier transport.
  • Medical Equipment: These pumps help cool down MRI machines, making sure we get clear and detailed medical scans.
  • Cryogenic Storage: They're essential for keeping biological samples and tissues super cold, which is crucial for research and medical purposes.

Positive Displacement Pump Applications

  • Aerospace: Positive displacement cryogenic pumps are a big deal in rocket propulsion, where precision and reliability are everything.
  • Labs: They're used in labs to carefully move super cold fluids for scientific experiments.
  • Energy Industry: In the energy world, these pumps handle cryogenic fuels like liquid hydrogen and oxygen, and they do it really well.

Types of Cryogenic Pumps and Their Applications

 Pump Type Main Characteristics Common Applications Centrifugal Pump High-flow, low-pressure LNG plants, medical imaging, cryogenic storage Positive Displacement Pump Precise control, high-pressure, reliable Aerospace, laboratories, energy industry


Key Applications of Cryogenic Pumps

  • Medical: Cryogenic pumps have a crucial role in the medical field, where precision and reliability are absolutely essential.
  • Aerospace: When we think about exploring space, cryogenic pumps are the unsung heroes that make rocket propulsion possible.
  • Energy: The energy industry depends significantly on the power of cryogenic pumps, especially in the production of liquefied natural gas (LNG).

Are There Safety Concerns Associated with Cryogenic Pumps?

It's crucial to recognize that using cryogenic pumps involves particular safety measures. Let's pause for a moment to review essential safety guidelines and precautions to guarantee the secure use of these pumps.

Protective Gear

When working with extremely cold cryogenic fluids, it's essential to wear the right gear for your safety. This means insulated gloves, a face shield, and suitable clothing to stay warm and protect against any splashes.

Ventilation and Containment

Cryogenic fluids may emit potentially harmful gases when they transition into vapor. To avoid the buildup of these gases, it's crucial to ensure proper workplace ventilation and containment systems.

Avoidance of Oxygen-Enriched Atmospheres

Additionally, these fluids can replace oxygen, leading to areas with lower oxygen levels. Workers should receive training to identify and stay clear of enclosed spaces where such oxygen displacement could occur.

Importance of Training

Proper training is essential for ensuring safety while handling these pumps. Insufficient training can be risky for both seasoned professionals and newcomers. Emphasizing the significance of thorough training programs that encompass the safe use, operation, and upkeep of cryogenic pump systems is crucial.

If you want to learn more, please visit our website Cryogenic Liquid Pump.

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