8-026 BLACK FKM 90D BACK-UP RING

Ordered as VBU90026, this is an AS568-026 black Viton® (FKM) 90 Shore A Back-Up Ring built to an inside diameter of 1.239 in (31.47 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 1.379 in (35.03 mm). The back-up ring bridges the extrusion gap so the primary seal holds its shape under load.

Expect good resistance to petroleum oils and fuels, aggressive chemicals, and many acids. That behavior comes from the compound itself: Viton® (FKM) is specified for very low compression set at elevated temperature, excellent resistance to compression set and permeation. Rated temperature range runs from -15°F (-26.1°C) to 400°F (204.4°C) in continuous service. Applications involving hot water and steam or ketones and esters call for a different compound.

Typical settings include semiconductor equipment, automotive fuel systems, and oil and gas.

Stocked as VBU90026 and sold individually. Unit weight is approximately 0.3553 g. Application requirements vary, so validate compatibility with your process conditions prior to installation. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.