Oring Cad
AS568-228 Buna-N 70 Duro Black O-Ring for 2-1/4 ID X 1/8 CS

Buna-N O-Rings 70 Duro Black BN700100-228

$ 0.419 per Each
Minimum Order Quantity (MOQ): 100
On Backorder

Material Buna-N
Cross Sectional Shape Round
Hardness 70
Dash 228
Fractional
  • ID: 2-1/4
  • CS: 1/8
  • OD: 2-1/2
Actual (Inch)
  • ID: 2.234 ± 0.020
  • CS: 0.139 ± 0.004
  • OD: 2.512
Actual (Metric)
  • ID: 56.74 ± 0.50
  • CS: 3.53 ± 0.10
  • OD: 63.800

Buna-N (Nitrile) O-rings are made from a synthetic rubber copolymer of acrylonitrile (ACN) and butadiene. They are among the most widely used sealing materials due to their excellent resistance to oils, fuels, and many chemicals. Nitrile O-rings provide high mechanical strength, outstanding wear resistance, and good tensile strength, making them ideal for automotive, industrial, and aerospace applications.

Buna-N Recommended Uses

Seals and gaskets, fuel systems, hydraulic systems, oil and gas industry, automotive applications, general-purpose applications.

Buna-N Not Recommended

Brake fluid, ozone, UV exposure, phosphate esters, chlorinated hydrocarbons, aromatic hydrocarbons, ketones, strong acids, atmospheric aging.

Buna-N Limitations

  • Not suitable for ozone, sunlight, or weathering exposure.
  • Limited performance in high-temperature environmen.
  • Not ideal for strong acids and alkalis.
  • Not recommended for applications requiring low compression set.
Buna-N Usable Temperature Range

-30 to 250°F (-34 to 121°C)

Buna-N Also Known As

Buna-N, Nitrile, NBR, Nitrile Butadiene Rubber.