428 PTFE SOLID BACKUP RING FDA

This back-up ring is supplied in AS568-428 white PTFE (Teflon) 55 Shore D supplied with an inside diameter of 4.85 in (123.19 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 5.4 in (137.16 mm), catalogued under part number TST428SO. It bridges the extrusion gap so the primary seal holds its shape under load.

PTFE (Teflon) is valued for near-universal chemical inertness and excellent dielectric properties. Expect good resistance to solvents, nearly all industrial chemicals, and strong acids and bases. Published continuous service range is -65°F (-53.9°C) to 500°F (260°C). Verify compatibility before use with elemental fluorine at temperature or molten alkali metals.

Typical settings include semiconductor fabrication, pharmaceutical and biotech, and food and beverage.

Reference part number TST428SO when ordering; the item is sold individually. Review your operating media and conditions against this specification before installation. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.