This back-up ring is supplied in AS568-147 black Buna-N (Nitrile) 90 Shore A supplied with an inside diameter of 2.675 in (67.95 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 2.881 in (73.18 mm), catalogued under part number HB90147. It bridges the extrusion gap so the primary seal holds its shape under load.
Buna-N (Nitrile) is specified for an economical choice for high-volume maintenance programs, strong abrasion and tear resistance. This material stands up to hydraulic fluids, petroleum-based oils, and propane and butane. Service temperature is rated from -40°F (-40°C) through 250°F (121.1°C). It should not be specified for service in ozone and direct sunlight or ketones.
You will find this material specified across agricultural equipment, fluid power, and hydraulic and pneumatic systems.
Order part number HB90147, sold individually. Unit weight is approximately 0.7955 g and nominal inside diameter is listed as 2 11/16 inch. 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.
Description 8-147 BLACK BUNA 90D BACK-UP RING
Actual Cross Section 0.103 inch (2.62 mm)
Actual Inside Diameter 2.675 inch (67.95 mm)
Actual Outside Diameter 2.881 inch (73.18 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings