Case studies

Omniseal® Rotary Lip Seals
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Generator Seal In Hybrid Engine Aircraft

    Mark Scoular
Aviation High Speed Low Coefficient of Friction High Durability
Aviation Hybrid Engine Aircraft


Recent advances in electrical motors, energy storage systems, and power electronics converters (PEC) are leading to aircraft becoming increasingly electrical. However, hybrid technologies are also a viable option for greener air travel. These hybrid engines convert several power sources to the relevant system of the aircraft, adjusting power supply to actual needs during flight. This makes power converters in hybrid engines a critical part, and their efficiency of utmost importance. 


Compact design and high efficiency entail a high speed rotating shaft (surface speed superior to 40 m/s – 7900 ft/min), which connect the turbine and the power converter. The generator shafts rotate at variable speed where the rotating shaft seal must allow very low leakage on the complete range of speed. To minimize the downtime of the engine, the seal needs to last the lifetime of the engine.


Omniseal Solutions designs lip seals that enable compact design, high speed sealing & excellent durability. Because of its extremely tough, long wearing jacket material showing a good resistance to wear, our polymer lip seals are trusted by our customer. 

Aviation Hybrid Engine Generator Seal
Omniseal Rotary Lip Seal Series 31 Group

A lasting sealing solution for lighter weight & cleaner air travel.


  • Lifetime protection of the bearings against environment (dust sand, salt spray, etc.)

  • No oil leak at variable speeds up to high speed  

  • Compact seal design fits compact overall design, simplifying integration and reducing overall weight



  • Omniseal®Rotary Lip Seal, Series 31


  • Generator in hybrid engine


  • High-Performance Polymer Material A27

Precision part

  • Custom Lip Seal

Technical details

  • Media: Jet Oil

  • Temperature: -40°C to 150°C (-40°F to 302°F)

  • Speed: up to 44 m/s

  • Pressure different up to 10 PSI (0.7 BAR)

  • Counter face: Chromium hardened shaft


Tags: Aviation High Speed Low Coefficient of Friction High Durability