TST281SO is an AS568-281 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 14.984 in (380.59 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 15.262 in (387.65 mm). In service, this back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.
PTFE (Teflon) is known for one of the lowest coefficients of friction of any solid and non-stick, non-contaminating surface characteristics. The compound resists solvents, strong acids and bases, and nearly all industrial chemicals. Continuous operating temperature is published at -65°F (-53.9°C) to 500°F (260°C). Applications involving molten alkali metals or service requiring elastic recovery call for a different compound.
Common environments for this compound include pharmaceutical and biotech, aggressive-media pipelines, and laboratory equipment.
This item is sold individually under part number TST281SO. Nominal inside diameter is listed as 15 inch. Review your operating media and conditions against this specification before installation. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.
description 281 PTFE SOLID BACKUP RING FDA
Actual_CS 0.139 inch (3.53 mm)
Actual_ID 14.984 inch (380.59 mm)
Actual_OD 15.262 inch (387.65 mm)
ProductCode Description O-Rings - Backup Rings