VBU90263 is an AS568-263 black Viton® (FKM) 90 Shore A Back-Up Ring with an inside diameter of 7.234 in (183.74 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 7.512 in (190.8 mm). In service, this back-up ring bridges the extrusion gap so the primary seal holds its shape under load.
As a material, Viton® (FKM) is known for excellent resistance to compression set and permeation, outstanding high-temperature capability. It resists aromatic hydrocarbons, chlorinated solvents, and engine and transmission fluids. Rated temperature range runs from -15°F (-26.1°C) to 400°F (204.4°C) in continuous service.
It sees regular use in semiconductor equipment, chemical processing, and high-temperature process equipment.
Reference part number VBU90263 when ordering; the item is sold individually. Review your operating media and conditions against this specification before installation. For a size or compound outside the standard catalog, APG can quote from a print or sample.
description 8-263 BLACK FKM 90D BACK-UP RING
Actual_CS 0.139 inch (3.53 mm)
Actual_ID 7.234 inch (183.74 mm)
Actual_OD 7.512 inch (190.8 mm)
ProductCode Description O-Rings - Backup Rings