Non-Contacting Face Seals​

At Qualiseal, technology from one industry often translates into success in another. Our non-contacting face seals are the perfect example.

Non-contacting face seals are hydrodynamic film-riding seals that have been successfully used in industrial pump and compressor applications for decades, and are now increasingly finding their way into demanding aerospace applications where the hydrodynamic features can be even more beneficial. Qualiseal designs hydrodynamic features into the face of the mating ring. As the mating ring rotates, these features force air into a converging gap in the sealing surface, causing a pressure increase between the primary sealing elements. Once the pressure becomes great enough, the faces separate and the part operates in a hydrodynamic or non-contacting mode. The hydrodynamic features use air from the inside diameter to generate lift. A static sealing dam prevents leakage when the part is not rotating.

In many aerospace applications, the rapid thermal transition, constantly changing pressures and high altitude conditions demand solutions where seal flatness must be maintained reliably over the long haul. Using a non-contacting seal enables the face seal and mating ring to operate virtually leak-free and experience almost no wear.

Click here to download a Qualiseal non-contacting face seal success story.

Ideal For:

  • High-stakes environments where virtually zero leakage is required


  • Significantly lower heat generation and reduced wear compared to contacting face seals
  • Virtually zero leakage
  • Robust design does not require special coatings or materials
  • Can fit into same space as existing contacting face seals
  • Robust performance and greater life expectancy

Operating Conditions (custom design can permit higher limits):

  • Pressure from 1.5 PSIA (10.3 kPa) to 100 PSID (689 kPa)
  • Temperatures: -65°F (-54°C) to over 1,000°F (537°C)
  • Speeds to 50,000 FPM (254 m/s)

Design Configurations:

  • Can utilize either an O-ring on the outer diameter in a slip fit application, or can be designed to press fit into the seal bore of your unit
  • Unbalanced or balanced designs
  • Several elastomeric compounds, metal bellows or spring energized secondary sealing options are available for a variety of fluid and temperature applications
  • Take-apart or unitized seal design
  • Seal designs incorporate seal face material grades to encompass a wide range of applications, including high-pressure velocity (PV) or extreme vibration applications

Primary Face Materials:

  • Carbon
  • Bronze
  • Silicon Carbide
  • Tungsten Carbide
  • Others

Secondary Seal Configurations:


  • Integrated Drive Generators (IDG)
  • Starters
  • Gearboxes
  • Pumps (Various Fluids)

Industries Served:

  • Aerospace
  • Industrial
  • Military

Contact us to learn more about our Non-Contacting Face Seals.