Why use PTFE seals?
Polytetrafluoroethylene (PTFE) is a thermoplastic polymer. PTFE seals can be used in a variety of sealing applications. It’s suitable when application conditions exceed parameters of elastomeric seal use but not to the extent of a metal seal.
What is PTFE?
It has a high melting point (342 °C) and morphological characteristics. These allow seal components made from virgin PTFE to be used continuously at service temperatures of up to 260 °C. With the addition of fillers – up to 300°C. It has the unique ability to resist material degradation, heat-aging and alteration in its physical properties during temperature cycling. Alongside this rare combination of material characteristics, PTFE also has unlimited shelf life.
Why use PTFE seals?
Notably PTFE demonstrates extraordinary chemical resistance. The intrapolymer chain bond strengths preclude reactions with most chemicals, thereby making it chemically inert at elevated temperatures and pressures with virtually all industrial chemicals and solvents. Only a few media (some molten alkalis) are known to react with PTFE seals making them the perfect sealing solution for highly aggressive chemical applications.
PTFE also has the lowest friction coefficient of any known solid. It has self-lubricating capabilities which offers continuous dry running ability in dynamic sealing applications and has superb stick/slip capabilities.
Focus on dry coatings
The advantages of using PTFE in sealing applications are multiple:
- Functionality at high and low temperatures
- Dynamic sealing with high wear capabilities
- High pressure sealing (using combinations of PEEK back-up rings)
- Compatibility with highly aggressive chemical combinations.
Our range of PTFE seal products include back-up rings, rod and piston seals, slipper seals and spring energised seals in a wide variety of sizes. Materials depend on application requirements. However, we offer a wide range from Virgin PTFE or including filler combinations of MoS2, glass, carbon, carbon fibre, graphite, and bronze.
These characteristics make PTFE seals perfect for the demanding applications involved in Oil & Gas, Aerospace, Automotive and Chemical Process markets (to name but a few). Ceetak’s engineering team are experienced in the design of PTFE sealing solutions to meet the complex specifications these types of application demand.
Read our overview and more detail about PTFE seals HERE