APG stocks the HB90263, an AS568-263 black Buna-N (Nitrile) 90 Shore A Back-Up Ring supplied 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). A back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.
Expect good resistance to propane and butane, water, and petroleum-based oils. Buna-N (Nitrile) is known for strong abrasion and tear resistance, reliable performance in both static and dynamic service. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C). It is not the right choice where polar solvents or strong acids are present.
It sees regular use in general industrial maintenance, construction equipment, and fluid power.
This item is sold individually under part number HB90263. Unit weight is approximately 2.7833 g. As always, verify media compatibility and operating conditions against the requirements of your specific application.
description 8-263 BLACK BUNA 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