As industries continue to push the boundaries of temperature, pressure and process reliability, cryogenic applications remain one of the most demanding environments for rotating equipment.
From LNG processing and industrial gas production to hydrogen applications and aerospace operations, sealing systems operating at ultra-low temperatures must deliver uncompromising performance under extreme conditions.
Flexaseal Australasia continues to support Australian industry with engineered cryogenic sealing solutions designed to improve reliability, safety and operational efficiency in some of the harshest service environments.
What makes cryogenic sealing so challenging?
Cryogenic applications typically involve fluids operating below -150°C, including liquid nitrogen, oxygen, argon, LNG and liquid hydrogen. At these temperatures, conventional sealing technologies can struggle due to:
- Thermal contraction of components
- Material brittleness
- Lubrication challenges
- Vapour formation and flashing
- Increased leakage risks
- Extreme pressure and temperature cycling
Maintaining seal face stability and preventing leakage under these conditions requires specialised engineering, precision manufacturing and carefully selected materials.
A real-world cryogenic sealing challenge
Flexaseal’s first major cryogenic sealing project began more than 20 years ago through its Brazil operation. Working closely with a large cryogenic gas facility, the Flexaseal engineering team spent extensive time identifying the root causes of recurring seal failures and safety concerns within the plant’s cryogenic pumps.
The facility utilised Grofe cryogenic pumps fitted with formed bellows assemblies. While the formed bellows could handle operating temperatures as low as -253°C, the design created excessive face loading and heat generation at the sealing faces.
This presented a serious operational risk.
In cryogenic applications involving flammable liquids such as liquid hydrogen, even small amounts of evaporation can create dangerous conditions. Just one litre of liquid hydrogen can expand into hundreds of litres of gas, rapidly creating a potentially flammable atmosphere that threatens both personnel safety and environmental compliance.
Engineering a safer solution
To overcome the issue, Flexaseal engineers adapted their proven edge welded metal bellows technology specifically for cryogenic service.
The solution incorporated:
- 347 stainless steel edge welded bellows for improved strength and stability at ultra-low temperatures
- A precision-controlled spring rate to reduce face loading
- Cryogenic-grade carbon seal faces to minimise friction and heat generation
- Self-lubricating materials to improve sealing performance and stability
By significantly reducing heat generation at the seal faces, the upgraded design improved the stability of the liquid gases while delivering safer and more reliable operation.
The results were substantial.
Following conversion to the Flexaseal cryogenic mechanical seal design, the facility achieved a mean time between failure (MTBF) of 6-8 months — effectively doubling the previous seal life of 3-4 months achieved with the original formed bellows assemblies.
For a facility transporting and processing cryogenic gases, the additional operating life delivered significant operational and safety benefits while reducing maintenance frequency and downtime.
Supporting emerging hydrogen and LNG industries
As Australia continues investing heavily in LNG infrastructure and hydrogen production, cryogenic seal technology is becoming increasingly important across the energy sector.
Hydrogen presents unique sealing challenges due to its small molecular size, low viscosity and extremely low operating temperatures when liquefied. Seal reliability and emissions control are critical considerations for operators focused on both efficiency and environmental compliance.
Flexaseal continues to advance its cryogenic sealing technologies, including ongoing development of non-contacting cryogenic gas seals and labyrinth sealing technologies designed for the next generation of industrial applications.
Applications across industry
Cryogenic sealing systems are commonly used across a wide range of industries and processes, including:
- LNG production and transport
- Industrial gas processing
- Hydrogen production and storage
- Chemical manufacturing
- Aerospace and defence
- Pharmaceutical processing
- Air separation plants
Flexaseal manufactures a line of stationary edge welded metal bellows component seals for cryogenic pumps such as Cryostar, ACD, Grofe, JC Carter, Airco Paul, and Cosmodyne just to name a few.
Local support backed by global expertise
With demand for specialised sealing technologies continuing to grow across Australia, access to experienced and responsive engineering support is more important than ever.
Flexaseal Australasia works closely with end users, OEMs and maintenance teams to deliver application-specific sealing solutions backed by decades of global sealing expertise. Most importantly, we move at your speed – fast response, shorter lead times, and prompt turnaround on repairs.
As cryogenic applications continue expanding across LNG, hydrogen and industrial gas sectors, selecting the right sealing partner can make a significant difference to equipment reliability, maintenance costs and operational safety.
Discover more at flexaseal.com. For Australian sales and service, contact sales_aus@flexasealau.com or 1300 762 548
