Enclosed in a metal support, PTFE envelope gaskets help provide a secure seal in applications specific to certain industries.
Industries that operate applications in gas and liquids, high-pressure and FDA applications, pharmaceuticals, and more.
At SSP, we stock a wide range of gasket types and sizes to ensure that you have access to the most suitable sealing solution for your application.
To find out more, call 01535 274 776.
What is PTFE envelope gasket?
A composed gasket with an envelope of PTFE that has an inlay (note: the inlay material can vary to suit the intended application, and we will look at these options in more detail below).
Typically made from PTFE (hence the name), this gasket type has a high melting point and good chemical stability. It is this outer layer (the PTFE) that serves as a barrier to chemical attacks, whereas the inner layer offers flexibility and resilience.
The metal core is the primary component of the gasket and can be made from a variety of materials. It is also this section of the gasket that is shaped like an envelope in order to provide support to its non-metallic parts.
When these two layers are combined, the gasket can maintain its integrity while continuing to provide a tight seal.
It’s important to note that this type of gasket does not have any foam or silicone fillers.
PTFE envelope gasket features
PTFE gaskets provide a reliable seal between two mating surfaces, with PTFE envelope gaskets offering a superior performance in applications operating within high temperatures and low pressures.
They have minimal creep relaxation and offer precise dimensional accuracy.
PTFE envelope gaskets are also available in various sizes and can be custom-made if required.
The metal support surrounding the gasket provides the seal with the necessary strength and rigidity, creating a robust seal between the two mating surfaces.
The non-reactive nature of polytetrafluoroethylene ensures that the PTFE jacket (envelope) covering the softer core material, i.e., EPDM or Viton, is not only flexible but also chemically resistant.
Benefits of PTFE envelope gasket
- Corrosion resistant – this means degradation is reduced, so there is no need for frequent replacements or ongoing maintenance.
- Excellent durability – long-lasting, remaining strong over time, offering a consistent sealing performance
- The gasket is self-lubricating
- Offers low friction and non-stick properties, adapting to the environment as required.
- Can accommodate expansion or contraction in the flange area with ease
- Resistant to pressure – PTFE gaskets have a good seal connection capacity due to their low surface compression.
- Adaptable – can seal small and large areas, all while maintaining a high bolting load.
- Resists contamination
- Provides thermal and electrical insulation
- Has a high chemical resistance
- Easy to install and remove
Applications of PTFE envelope gaskets
PTFE envelope gasket applications include:
- Enamel flanges
- Plastic pipes
- Rubber and steel flanges
- Chemical processing applications
- Food and beverage sector
- High-pressure and high-temperature applications
- Aerospace
Found also within the automotive industry, this particular type of gasket provides a robust seal between engine components and required hoses and tubes.
They are also used within gas containment systems to prevent leaks and unwanted contaminants from entering the application, as well as in underground storage tanks where leak prevention is critical.
Types of PTFE envelope gaskets
PTFE envelope EPDM gasket: With an EPDM core, this gasket is resistant to ozone, heat, and weathering, making it great for applications exposed to harsh environmental conditions. A cost-effective option that is readily available.
PTFE envelope Viton gasket – the perfect option in specific applications where resistance to extreme temperatures and chemicals is a must. Mainly found in specialist industries such as aerospace and the automotive sector.
PTFE envelope FKM gasket – offering greater chemical resistance than Viton, makes this the gasket of choice for the chemical processing industry. Robust in nature and offering a long service life, this type of gasket can prove vital in safety-critical applications.
Why use PTFE envelope gaskets?
Available in various dimensions and thicknesses, PTFE envelope gaskets can also be customised, making them suitable for all applications.
However, we advise all our customers to carefully consider the material choice of their gasket, ensuring it meets industry standards and all relevant regulations and requirements to ensure the gasket’s long-term performance.
Make sure to check pressure limits and be aware of temperature ranges, and work with a professional and knowledgeable gasket supplier who can help answer your questions and provide you with the right sealing solution.
When choosing the right gasket supplier, check their quality assurances, certifications, their quality control processes, reputation, range of products, responsiveness, and level of customer support. You want to have complete peace of mind that the sealing solutions you are investing in are the best in the industry – these are critical to your application.
At SSP, we help you to make the best and most informed decision to meet your needs.
Helping you choose the right gasket to ensure high-quality performance, safety, and efficiency, always.
Speak to a member of our team today to see how we can help.
Call 01535 274 776
