8-436 BLACK FKM 90D BACK-UP RING

Ordered as VBU90436, this is an AS568-436 black Viton® (FKM) 90 Shore A Back-Up Ring with an inside diameter of 5.85 in (148.59 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 6.4 in (162.56 mm). The back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.

Viton® (FKM) is known for the industry benchmark where nitrile reaches its thermal limit and very low compression set at elevated temperature. It resists many acids, petroleum oils and fuels, 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 is not the right choice where low-molecular-weight organic acids or ketones and esters are present.

Common environments for this compound include aerospace, semiconductor equipment, and high-temperature process equipment.

Reference part number VBU90436 when ordering; the item is sold individually. Unit weight is approximately 13.777 g and nominal inside diameter is listed as 5 7/8 inch. Check the compound against your process media, pressure and temperature before committing to a design.