ISO-63 Centering Ring, PTFE

These ISO DN 63 centering rings are made of PTFE with Viton® (FPM) rubber O-rings and are used to seal both ISO-K and ISO-F vacuum flanges. The centering ring forms the vacuum seal between the two mating ISO-K or ISO-F flange faces. ISO-K fittings are quick to assemble using claw clamps and can be connected together in any orientation. The claw clamp hooks into a ridged groove in the back side of the ISO-K flange. ISO-F fixed flange vacuum fittings have a bolt circle where bolts align the two flanges. These ISO 63 centering rings are commonly used to build process vacuum plumbing and systems for industrial and high vacuum applications.

PTFE can handle high temperatures up to 250°C, is chemical resistant to nearly all chemicals, doesn't corrode, and can act as an electric insulator between other metal KF parts. 

The o-rings have been cleaned and baked out before shipping.

Maximum bakeout temperature is 200 °C (limited by the the o-ring).

Other o-ring materials available upon request. 

Silicone, FFKM (kalrez), low outgassing viton, etc