PTFE encapsulated O-Rings are designed to combine the sealing properties of the rubber O-ring with the chemical resistance of Teflon® PTFE. They are generally manufactured from Viton® or silicone rubber and are coated in a thin moulded layer of Teflon FEP or PFA. This provides a unique seal popular for high friction and aggressive chemical applications. FEP encapsulated O-rings are our most common and are resistant to solvents and chemicals (except for alkali metals, fluorine and some halogenated compounds at high temperatures). They have a low coefficient of friction and a very low permeability to gases making them suitable for harsh environments. PTFE encapsulated O-rings also have a good elastomeric memory. We can also supply rigid Teflon® PTFE O-rings which have a high compression set.
- Temperature (FEP Encapsulated O-Rings): -60°C to +205°C (260°C short term).
- Temperature (PFA Encapsulated O-Rings): -60°C to +260°C (300°C short term).
- Shore Hardness (Silicone): 85-90°A
- Shore Hardness (Viton®): 90-95°A
- Shore Hardness (Hollow Silicone): 75-80°A
Note: Below are our most common sizes, many others can be manufactured upon request.