• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar
  • Skip to footer

Sealing & Contamination Control Tips

Fluid Power Sealing and Contamination Control Information and Resources

  • News
  • Contamination Control
  • Filtration
  • Seals
  • Fluids
  • Design Guides
  • Advertise
  • Subscribe
You are here: Home / Blogs / When should you use PTFE seals?

When should you use PTFE seals?

September 22, 2021 By Mary Gannon Leave a Comment

Share

Being the fluid power professional you are, you know that Teflon is used for more than making pans slippery. However, you may not know that Teflon is a registered trademark of DuPont, discovered accidentally many decades ago and associated with non-stock coatings. PTFE is an acronym for polytetrafluoroethylene, which is also a fluorocarbon. DuPont trademarked another popular fluorocarbon, Viton, but that’s for another blog.

PTFE offers unique advantages for fluid power applications when standard elastomer seals cannot offer a sealing solution. The material is practically impervious to any form of harm a hydraulic system can throw at it. Heat, contamination and friction are no match for a PTFE seal, especially with the already limited bounds hydraulic systems play within.

PTFE seals AdobeStock_57765477
Polytetrafluoroethylene (PTFE) polymer, chemical structure

PTFE shrugs off excess heat to the tune of 500°F, which is well beyond the needs of any hydraulic system or actuator not literally exposed to open flame. Hydraulic fluid prefers to remain on the cooler side of 140°F, where it remains at an appropriate viscosity and without oxidation. However, specific applications may allow fluid to approach 200° or more using specialty fluids, requiring PTFE sealing technology.

PTFE is also the seal of choice for high-velocity applications, such as with high-speed cylinders. PTFE offers one of the lowest friction coefficients of any known material, so their use with high-velocity cylinders is widespread. In addition, their lack of static friction means they work well for motion control applications, where the piston must accelerate quickly and predictably.

Just as with heat, polytetrafluoroethylene is impervious to every hydraulic fluid designers could expose to the material, such as phosphate ester. The same can be said about environmental exposure, where seals such as a cylinder’s rod wiper may be exposed to a caustic or corrosive fallout. This natural resistance offers the seal material unlimited shelf life, while other materials may degrade when left exposed to heat, oxygen or light for an extended period.

The downside to PTFE is its plastic nature, which makes the material prone to leakage or bypass when not applied correctly. Rubber energizers are often required to improve contact with its sealing surface, which reduces the tendency to bypass. Also, because of the plastic nature of PTFE, it can sometimes make installation difficult, so intelligent and thoughtful design of the parent component’s sealing pockets and cavities should be considered. For example, a flange or retainer to hold a cylinder’s rod seal makes installation possible compared to a machined pocket requiring the seal to be twisted and bent before installation.

You may also like:

  • COG Vi 900 FKM elastomer seals for oil and gas
    When should you use Viton seals?
  • The Hallite 606 single-acting, single lip asymmetric piston seal is moulded in Hythane 181, Hallite’s high-performance polyurethane, for easy installation and low-temperature performance
    What are the benefits of urethane seals?
  • Hardened and cracked elastomer seal. Image courtesy of Colonial Seal
    Effects of aging on elastomer seals
  • An example of extrusion nibbling. Image courtesy of Trelleborg Sealing Solutions
    What causes O-ring failures?

  • Basics of static sealing

Filed Under: Blogs, Featured, Seals

Reader Interactions

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Primary Sidebar

Fluid Power World Digital Editions

Fluid Power World Digital Edition

Browse the most current issue of Fluid Power World and back issues in an easy to use high quality format. Bookmark, share and interact with the leading design engineering magazine today.

Fluid Power Design Guides

fluid
“sact
EXPAND YOUR KNOWLEDGE AND STAY CONNECTED
Get the latest info on technologies, tools and strategies for Fluid Power Professionals.

Footer

Sealing and Contamination Tips

Fluid Power World Digital Network

  • Fluid Power World
  • Mobile Hydraulic Tips
  • Pneumatic Tips
  • Hose Assembly Tips
  • Leadership in Engineering

Sealing & Contamination Control

  • Subscribe to Fluid Power World
  • Videos
  • Advertise with us
  • About us

Copyright © 2025 · WTWH Media, LLC · Privacy Policy