APG stocks the H3.1X79.4, a black Buna-N (Nitrile) 70 Shore A O-Ring supplied with an inside diameter of 79.4 mm (3.126 in), a cross section of 3.1 mm (0.122 in), and an outside diameter of 85.6 mm (3.37 in). An o-ring provides a reliable static or dynamic seal by deforming into its gland under assembly load. Source specification: Metric O-RING, JIS G80.
The material holds up against greases and lubricants, hydraulic fluids, and petroleum-based oils. Buna-N (Nitrile) is known for reliable performance in both static and dynamic service, low compression set under sustained load. Rated temperature range runs from -40°F (-40°C) to 250°F (121.1°C) in continuous service. It should not be specified for service in automotive brake fluid or strong acids.
Common environments for this compound include hydraulic and pneumatic systems, construction equipment, and agricultural equipment.
Reference part number H3.1X79.4 when ordering; the item is sold individually. Unit weight is approximately 2.4051 g. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. If you need a size, durometer or compound that is not listed, APG can cross-reference from a print, a sample or a competitor part number.
description 3.1MM CS X 79.4MM ID BLACK BUNA 70D
uf_description2 METRIC O-RING, JIS G80
Actual_OD 85.6 mm (3.37 inch)
Actual_CS 3.1 mm (0.122 inch)
Actual_ID 79.4 mm (3.126 inch)
ProductCode Description O-Rings - Metric - Commodity