Space Insights: Boosting Launch Vehicle Performance

By Kha Le (Apr 2025)

Cryogenic temperatures are one of the most challenging environments and require cryogenic materials such as high-performance seals - not only for performance and cost, but also success and safety of the mission. This is especially true when engineering sealing solutions for cryogenic applications in space such as fuel tanks and valves. What goes into making quality sealing materials for this type of extreme environment? In this blog, our space expert, Kha Le, shares valuable insights about advanced sealing solutions and high-performance materials that are enabling greater reliability and efficiency in launch vehicles.

What are the main challenges of sealing solutions in space launch vehicles?

Sealing components in space launch vehicles face extreme challenges due to the harsh conditions encountered during launch, operation, and re-entry, including ultra-high pressures, cryogenic temperatures, rapid thermal cycling, vibration, and mechanical shocks. Along with operating conditions, the handling of aggressive chemicals such as cryogenic and hypergolic propellants also adds complexity to sealing system requirements.

Conventional and standard sealing solutions often fail in these challenging environments, due to metals and polymers becoming brittle or losing elasticity, which leads to leakage and potential mission-critical failures. The following are the critical challenges space companies face and the advanced solutions they use to ensure successful missions.

1. Extreme Temperatures & Thermal Cycling

   • Cryogenic Challenges: Materials tend to lose flexibility and become brittle at cryogenic temperatures, compromising sealing integrity.

   • Thermal Cycling: Rapid shifts from cryogenic to high temperatures during launch and re-entry add stress to the seals, causing potential material fatigue and dimensional instability.

2. Pressure Fluctuations & Mechanical Stresses

   • High Pressures: Sealing solutions must withstand extreme pressures generated by propellant systems and flight dynamics.

   • Mechanical Loads: Vibrations and shocks during liftoff and flight place additional mechanical stress on seals, demanding exceptional resilience.

3. Material Wear & Chemical Resistance

   • Exposure to aggressive chemicals and prolonged use exacerbate wear, requiring seals with superior friction and wear control properties.

What solutions does Omniseal Solutions have in place to help tackle these challenges?
 

To solve these key challenges, Omniseal Solutions developed polymer, spring-energized seals, which are engineered for high performance and reliability in extreme environments. These seals combine low-friction polymer materials (e.g., PTFE) with an internal metal spring that applies consistent radial or axial force against sealing surfaces, addressing issues like material wear, thermal expansion, and pressure variability. To ensure optimal sealing performance across a wide range of extreme conditions, advanced seal designs and spring-energized technologies are employed. Two key innovations include:

• Unique Spring Designs: Designed for dynamic and static conditions, these custom seals maintain integrity even under extreme pressure and temperature fluctuations. Design options such as V-springs, canted coil springs, and helical coil springs are selected based on specific application requirements, i.e., high pressures, low temperatures, cryogenic, or vacuum.

• Omniseal® RACO® Spring-Energized Seals: Optimized for cryogenic static face seal applications, these U-shaped seals provide high sealing contact force and are resistant to shrinkage at cryogenic temperatures. A high-performance polymer jacket energized by a corrosion-resistant, heavy-duty RACO® spring delivers exceptional spring force along the sealing lip. By providing a robust, leak reduction barrier, the spring-energized seals ensure the structural integrity of spacecraft and ground support equipment throughout their lifecycle. Their ability to handle the mechanical stresses, thermal extremes, and aggressive chemicals encountered in space missions makes them indispensable for modern launch vehicles.

How has Omniseal Solutions innovated in cryogenic sealing technology?

During a pivotal era in the 1950s and 1960s, Omniseal® spring-energized seals emerged as critical components to prevent leakage and catastrophic failure in launch vehicles, which were causing millions of dollars in loss to key space companies such as Aerojet General, North American Rocketdyne, and Lockheed. These seals were custom designed to withstand cryogenic temperatures and high-pressure conditions with exceptional resilience—technological feats that revolutionized sealing reliability in extreme environments. 

A notable breakthrough was the Omniseal® RACO® spring-energized seals, developed by Roy Creath, a sealing pioneer from Southern California. Due to its unique U-shaped spring design, the sealing performance was robust enough to withstand severe temperature and pressure fluctuations typical of space launch vehicles and satellite applications. The ingenuity behind this engineered design ensured that spacecraft systems remained operational and secure even under the harshest conditions.Today, Omniseal Solutions continues to support its space customers through advancements in cryogenic and high-performance sealing technologies. Our dedicated teams of engineers and R&D experts are constantly innovating to address the evolving demands of the space industry: lighter materials, chemical exposure, wear resistance and more high-stress conditions. Combining materials science experience with advanced engineering principles, we can manufacture sealing solutions that uphold the structural integrity of critical aerospace systems in the most extreme environments. 

If you're curious about how our sealing technology started, check out "The Omniseal Origin - Our Race To Space." This video shares the story of how our engineers took on tough sealing and leakage challenges during the space race - developing solutions like helically wound springs, PTFE-jacketed seals, and the Omniseal® RACO® spring-energized seals specifically designed for cryogenic environments and that are still being used on modern space rockets today. That same drive to solve complex problems still fuels our work today, helping our space partners push the limits of exploration.

Would you like to hear more industry insights from our space experts? Click the above PRINT button for our full Q&A technical article!