More about Labyrinth Seals
Non Contact Labyrinth Seal Solutions
When it comes to seals, labyrinth seals are a standard design choice, and engineers have been researching and apply labyrinth seal technology for over one hundred years. We at Advanced EMC Technologies are a reliable source for advanced polymer seals solutions.
What Kind of Seal is a Labyrinth Seal?
A labyrinth seal is a type of dynamic mechanical clearance seal characterized by long life and low friction that is typically used to isolate areas of low pressure from areas of high pressure.
How Do They Work?
The word “labyrinth” usually brings to mind a maze full of complex, confusing passageways, which is an excellent description of how a labyrinth seal works.
Polymer labyrinth seals make it difficult for liquids to make their way through the seal barrier because of a complicated set of paths that a liquid or contaminant has to maneuver through in order to overcome the seal barrier. In fact, one of the goals of these complicated pathways is to create areas of turbulence and flow friction that reduce the kinetic energy of the contaminants trying to get in. Because of this, they outperform regular seals in keeping contaminants out and liquids in. Regular seals can do an outstanding job of keeping liquids in, but do not perform so well in keeping contaminants out.
Benefits of polymer labyrinth seals include:
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- Efficiency
- Ease of installation
- excellent reliability
Reliability is due to several factors:
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- Eorrosion resistance
- Gall resistance
- Labyrinth seals can maintain clearance during occasional rubs, unlike lip seals
PEEK labyrinth seals are generally specified as fixed tooth labyrinth seals. Sometimes they are referred to as rub tolerant seals. This is usually when reduced clearance is achievable and when the contact made between the seal and the rotating member cause the fixed teeth on the seal to deflect during contact without wear or damage to the rotor.
Torlon fixed tooth non-contact seals provide the same deflection characteristics of PEEK with the advantage of improved mechanical properties under prolonged service temperatures.
Typical locations where abradable seals are used in turbo machinery can generally classified into two groups:
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- Vane tip clearance seals
- Labyrinth clearance seals