568-251 PTFE ORINGS FDA

APG stocks the TFE251, an AS568-251 white PTFE (Teflon) 55 Shore D O-Ring measuring an inside diameter of 5.109 in (129.77 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 5.387 in (136.83 mm). An o-ring compresses into its gland to block fluid or gas migration across a joint.

PTFE (Teflon) offers non-stick, non-contaminating surface characteristics and excellent dielectric properties. Expect good resistance to nearly all industrial chemicals, oxidizing media, and solvents. Published continuous service range is -65°F (-53.9°C) to 500°F (260°C). It should not be specified for service in elemental fluorine at temperature or molten alkali metals.

You will find this material specified across pharmaceutical and biotech, laboratory equipment, and chemical processing.

TFE251 ships individually. Nominal inside diameter is listed as 5 1/8 inch. Check the compound against your process media, pressure and temperature before committing to a design. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.