APG stocks the TST216SO, an AS568-216 white PTFE (Teflon) 55 Shore D Back-Up Ring with an inside diameter of 1.109 in (28.17 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 1.387 in (35.23 mm). A back-up ring bridges the extrusion gap so the primary seal holds its shape under load.
PTFE (Teflon) is known for one of the lowest coefficients of friction of any solid and non-stick, non-contaminating surface characteristics. Expect good resistance to nearly all industrial chemicals, strong acids and bases, and solvents. Service temperature is rated from -65°F (-53.9°C) through 500°F (260°C).
You will find this material specified across food and beverage, semiconductor fabrication, and pharmaceutical and biotech.
TST216SO ships individually. Review your operating media and conditions against this specification before installation. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.
Description 216 PTFE SOLID BACKUP RING FDA
Actual Cross Section 0.139 inch (3.53 mm)
Actual Inside Diameter 1.109 inch (28.17 mm)
Actual Outside Diameter 1.387 inch (35.23 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings