PEEK (polyetheretherketone) is most often compared with PTFE. The two have multiple similarities including good temperature resistance, chemical inertness and dielectric strength. When it comes to pure physical strength however, PEEK moves ahead on two counts.
Piston ring seals
Piston rings are used primarily to aid wear absorption on the outer diameter of the piston shaft. PEEK is hard enough to withstand the extensive wear induced within the piston, but not hard enough to damage the metal components
Ball valve seats
Ball valve seats show a predominant preference for PTFE, as they require a soft material that yields easily to the shape of the ball valve.
Rotary shaft seals
We have developed compounded grades of PTFE with PEEK to cater to the rotary shaft seals market. The combination of PTFE and PEEK is a powerful one.
Ball and butterfly valve seats
A number of different thermoplastic materials are used in this application, including PTFE, Delrin and UHMWPE. PEEK finds acceptance specifically in applications with high pressures and temperatures.