When you require a sealing solution that can support your application across various temperature and pressure ranges, the material PTFE will be one of your first choices.
Known for its ability to withstand high temperatures, resist harsh chemicals, and remain intact in high-pressure environments, PTFE can and does offer it all.
However, with expanded PTFE (also known as ePTFE) now available, which sealing solution is best for your application? What are the differences between ePTFE vs PTFE, and what specifications should you be aware of before making your decision?
Differences between ePTFE and PTFE
What is PTFE?
When your application requires chemical and temperature resistance, the material PTFE offers the best sealing performance.
Standing for polytetrafluoroethylene, PTFE is a synthetic fluoropolymer.
Offering non-stick properties, PTFE industrial seals are cost-effective and suitable for applications that can see temperature ranges exceeding 260 degrees Celsius.
In addition, PTFE seals and gaskets also offer a low-friction surface (reducing wear and tear, hence extending the lifespan of both the seal and the equipment), they have a high electrical resistance, making them suitable for a variety of sectors, and their smooth surface is ideal for pipe flanges in order to provide a better and more robust seal.
Enduring even the harshest of environments, applications for PTFE are diverse. In fact,
PTFE sealing is suitable for:
- Food and drink sector
- Medical applications
- Electrical insulation
- Chemical industry.
What is expanded PTFE?
Expanded PTFE is what we call the microporous version of PTFE. It has all the similar properties of PTFE; however, ePTFE is suitable for applications that require a permeable material.
This microporous fluoropolymer material is soft, flexible, and can feel smooth and spongy to the touch, making it suitable for cords, sealing tape, or tubing.
When looking at the difference between PTFE and expanded PTFE, some of the benefits of ePTFE include:
- Material is non-toxic, making it incredibly hygienic (essential in some industries)
- It has a high linear strength, making it resistant to harsh chemicals
- It has a high temperature resistance
- At low pressure, ePTFE is watertight
- It offers UV resistance
- Provides a robust and tight seal due to its excellent radial expansion.
ePTFE seals and gaskets are typically used for:
- Medical devices
- Electronic insulators
- Applications within the oil and gas sector
- Pipework and flanges
- Environmental and fluidic filtration applications
- Vascular grafts and even reconstructive surgery.
Expanded PTFE can also be used in the medical profession in the form of implants, as it is used to create a mesh-like structure that allows seamless tissue integration in the body to occur.
Choosing ePTFE over PTFE
When looking to choose ePTFE over PTFE or vice versa, it’s important to understand the pros and cons of both materials as well as the benefits, to enable you to make the most informed decision, choosing the most suitable seal for your application.
For example, knowing that PTFE is a solid material that is long-lasting and corrosion-resistant can be critical. Understanding that this particular material doesn’t cause friction, it is non-corrosive, and it won’t contaminate an application’s content, making it suitable for the pharmaceutical industry as well as the food sector, and within chemical applications can be vital.
Extended PTFE, however, is a robust sealing material that can withstand high compression (ideal for high-pressure applications). This particular type of seal can stand firm against creep and flow and can adapt to the sealing surface with ease.
What’s more, with extended PTFE seals and gaskets, the seal can be modified and customised to meet your application’s specific requirements. Offering flexibility due to its elasticity and stretch at high temperatures, extended PTFE materials are also chemically resistant and water resistant at low pressure.
You will also find extended PTFE seals with diverse porosity levels, ranging from low to medium and high.
Industrial sealing
Both PTFE and extended PTFE are excellent for providing high-quality and robust sealing solutions for industrial applications.
However, if you are looking to meet the maximum safety demands in the sector, ePTFE is one of the best materials for seals and gaskets around.
With the ability to customise this to meet your application-specific requirements, extended PTFE is a seal that offers better performance across a wide range of environments.
At Specialist Sealing Products, we provide high-quality seals and gaskets in a range of material types to suit a wide selection of applications.
We know the importance of preventing leaks, which is why we work with you to better understand the environment and application the seal will be placed in to identify the most appropriate sealing solution for you.
Contact us today to find out more.
