PTFE (polytetrafluoroethylene, better known as Teflon®) and its derivatives like FEP and PFA, is one of the most inert and chemically resistant materials that an o-ring or seal can be made from. It has been described as the “slipperiest stuff in the world” because of its very low coefficient of friction. There are some elastomers today that approach PTFE’s chemical and heat resistance but their high cost can be a drawback. PTFE can be modified with fillers to improve its properties depending on the applications requirements.
PTFE O-rings are typically used in static applications while PTFE lip seals (with metallic springs or rubber used as an energizer) and piston rings will be used in tough dynamic applications where pressure and heat or high cycles are a problem. PTFE also makes excellent Backup Rings that boost the sealing capabilities of an o-ring to much higher levels.
PTFE can now be processed into soft joint sealing tape and gaskets by a special “expanding” process allowing its use in applications where a flange or sealing surface is less than ideal or needs a low bolt loading such as glass flanges.
MHEC manufactures different PTFE parts based on different specs.
