Extreme temperatures no sweat

Inside view into airplane jet engine
Date: 28.04.20
In the drive to make flying more sustainable, aircraft engine manufacturers constantly seek more efficient power units with lower fuel consumption. In practice, this means engines that can exceed +600 °F/316 °C. This poses new challenges for the critical sealing components that such engines require.

A step change in aviation fire sealing 

To meet the challenge, Trelleborg Sealing Solutions created the Ultra High Temp Seal for aviation customers. Its revolutionary makeup and design offer a solution to aircraft manufacturers developing engines that run hotter and more sustainably. 

 Quinn Collett, Senior Director of Global Technology, says: “The hotter an engine runs, the more thrust is obtained from the same amount of fuel, making the engine more efficient and lowering fuel consumption. Aircraft designers aim to run engines at continuously higher temperatures with the latest options operating at +600 °F/316 °C and beyond, significantly higher than their predecessors.” 

 At such extreme temperatures, specialized fire seals help ensure the safety of passengers onboard. Used in the fuselage, pylons, thrust reversers and engine applications, they act as a barrier to prevent airflow from one area of a plane to another during normal operating conditions, an important function. But even more crucially, they serve as a precaution in incidents that lead to fire, containing conflagrations to one section of an aircraft and enabling a safe landing within a 15-minute period. 

 

Not too hot to handle 

Collet continues, “Up until now, no high temperature fire seals existed that could operate up to +600 °F/316 °C and also meet all customer’s fire seal requirements. The Ultra High Temp Seal is completely unique. Its design overcomes the inherent silicone characteristic of relaxation and compression set at elevated temperatures; a major cause of failure in a fire seal’s ability to perform against all requirements. This means that the Ultra High Temp Seal can successfully operate in high temperature aircraft engine applications.” 
 

Proven in the heat of the moment 

Trelleborg performed a full test program to prove the product’s capabilities at different compression loads. In heat soak tests, the Ultra High Temp Seal performed better than other fire seals. In all cases it was below a 15% permanent set target. 

To manufacture the product, Trelleborg developed a proprietary methodology to integrate all components and make complex geometries. As the Ultra High Temp Seal eliminates the need for thermal protection of sealing elements, this provides a further weight saving and part count reduction, making assembly easier.  

The Ultra High Temp Seal is proven to operate at a temperature range from -40°F/-40 °C to up +600 °F/+316 °C while meeting all customer fire seal requirements. 

It is engineered to have a lifetime of 60,000 flight cycles (take off, flight and landing), dependent on application. The Ultra High Temp seal can also be a drop-in replacement for seals that do not currently meet all fire seal requirements, such as high-temperature operation, or for customers seeking extended life replacement seals. 

The seal meets the requirements of US Federal Aviation standard AC20-135 Powerplant Installation and Propulsion System Component Fire Protection Test Methods and Standards and Criteria, as well as ISO 2685:1998 Aircraft – Environmental Test Procedure for Airborne Equipment – Resistance to Fire in Designated Fire Zones.  

 When the heat is on, Trelleborg has the answer.

 

 

For more information, please visit: Seals